EP4606237A1

EP4606237A1 - Aerosol delivery system

Info

Publication number: EP4606237A1
Application number: EP24159390.4A
Authority: EP
Inventors: James Sheridan; Lewis CONNER; Steven Ly; Daniel Law; Scott BOHAM; Richard HAINES
Original assignee: Nicoventures Trading Ltd
Current assignee: Nicoventures Trading Ltd
Priority date: 2024-02-23
Filing date: 2024-02-23
Publication date: 2025-08-27
Also published as: WO2025176993A1

Abstract

An aerosol delivery system 810) generating an aerosol from an aerosol-generating substrate is described. The aerosol delivery system includes a cartridge (30) for use with an induction assembly of the aerosol delivery system. The cartridge comprises a recess (38) configured to receive a planar induction element (42), and a susceptor (34) comprising a planar surface positioned to be parallel to a plane defining the planar induction element and offset from the planar induction element in a direction perpendicular to the plane when the planar induction element is received in the recess. In this way, the planar induction element is able to induce current flow in the susceptor to inductively heat the susceptor and so vaporise a portion of the aerosol generating substrate in the vicinity of the susceptor.

Description

Field

The present disclosure relates to an aerosol delivery system, an induction assembly for use in the aerosol delivery system, a cartridge comprising a susceptor, a control unit for use with the induction assembly, and a method for operating the aerosol delivery system.

Background

Many electronic vapour provision systems, such as e-cigarettes and other electronic nicotine delivery systems that deliver nicotine via vaporised liquids, are formed from two main components or sections, namely a cartridge or cartomiser section and a control unit (battery section). The cartomiser generally includes a reservoir of liquid and an atomiser for vaporising the liquid. These parts may collectively be designated as an aerosol source. The atomiser generally combines the functions of porosity or wicking and heating in order to transport liquid from the reservoir to a location where it is heated and vaporised. For example, it may be implemented as an electrical heater, which may be a resistive wire formed into a coil or other shape for resistive (Joule) heating or a susceptor for induction heating, and a porous element with capillary or wicking capability in proximity to the heater which absorbs liquid from the reservoir and carries it to the heater. The control unit generally includes a battery for supplying power to operate the system. Electrical power from the battery is delivered to activate the heater, which heats up to vaporise a small amount of liquid delivered from the reservoir. The vaporised liquid is then inhaled by the user.
The components of the cartomiser can be intended for short term use only, so that the cartomiser is a disposable component of the system, also referred to as a consumable. In contrast, the control unit is typically intended for multiple uses with a series of cartomisers, which the user replaces as each expires. Consumable cartomisers are supplied to the consumer with a reservoir pre-filled with liquid, and intended to be disposed of when the reservoir is empty. For convenience and safety, the reservoir is sealed and designed not to be easily refilled, since the liquid may be difficult to handle. It is simpler for the user to replace the entire cartomiser when a new supply of liquid is needed.
In this context, it is desirable that cartomisers are straightforward to manufacture and comprise few parts, whilst providing a suitable amount of vapour upon activation of the heater. They can hence be efficiently manufactured in large quantities at low cost with minimum waste without comprising the user's vaping experience. Cartomisers of a simple design which allow for efficient heating are hence of interest.
Various approaches are described which seek to help address some of these issues.

Summary

According to a first aspect of certain embodiments there is provided a cartridge for use in an aerosol delivery system for generating an aerosol from an aerosol-generating substrate, the cartridge for use with an induction assembly, the cartridge comprising a recess configured to receive a planar induction element, and a susceptor comprising a planar surface positioned to be parallel to a plane defining the planar induction element and offset from the planar induction element in a direction perpendicular to the plane when the planar induction element is received in the recess.
In some examples in accordance with the first aspect, the recess is defined at least in part by the planar surface of the susceptor, the planar surface of the susceptor positioned to be adjacent to the planar induction element when the planar induction element is received in the recess.
In some examples in accordance with the first aspect, the recess forms a portion of an air path extending through the cartridge.
In some examples in accordance with the first aspect, the planar surface is offset from the planar induction element by an offset distance in a range of less than 2 mm; and optionally wherein the planar surface is offset from the planar induction element by an offset distance in a range of less than 1.5 mm.
In some examples in accordance with the first aspect, the susceptor comprises a plurality of apertures extending through the susceptor; and optionally wherein the plurality of apertures are arranged in a pattern, the number density of the plurality of apertures varying from a peripheral edge bordering the planar surface of the susceptor towards a centre of the planar surface of the susceptor.
In some examples in accordance with the first aspect, the cartridge comprises a reservoir for a liquid aerosol generating substrate, wherein the cartridge is configured to supply liquid from the reservoir to the susceptor; and optionally wherein the cartridge comprises one or more liquid flow channel for guiding liquid aerosol generating substrate from the reservoir.
In some examples in accordance with the first aspect, the cartridge comprises a sub-reservoir provided at or towards an opposite end of the susceptor to the reservoir, the sub-reservoir configured to hold a smaller volume of liquid aerosol generating substrate than the reservoir, and wherein the cartridge is configured to supply liquid from the sub-reservoir to the susceptor; and optionally, wherein the sub-reservoir is configured to hold a volume of liquid in the range of 0.2 % to 2.5 % of a volume of the reservoir.
In some examples in accordance with the first aspect, the planar surface is a first planar surface, wherein the susceptor comprises a second planar surface positioned to be parallel to the plane of the planar induction element and offset from the planar induction element in a direction perpendicular to the plane, when the planar induction element is received in the recess, the second planar surface being provided on an opposite side of the recess to the first planar surface; and optionally, wherein the recess is defined at least in part by the second planar surface of the susceptor, the second planar surface of the susceptor positioned to be adjacent to the planar induction element when the planar induction element is received in the recess.
In some examples in accordance with the first aspect, the susceptor comprises a first sheet providing the first planar surface and a second sheet providing the second planar surface, the first sheet separate from the second sheet; and optionally wherein a first thickness of the first sheet is in the range of one or more of 20 µm to 70 µm, 30 µm to 60 µm, and 40 µm to 55 µm, and / or a second thickness of the second sheet is in the range of one or more of 20 µm to 70 µm, 30 µm to 60 µm, and 40 µm to 55 µm.
According to a second aspect of certain embodiments there is provided an induction assembly for use with a cartridge in accordance with the first aspect, the induction assembly comprising a planar induction element, the planar induction element operable to induce current flow in a susceptor of the cartridge to inductively heat the susceptor, wherein the induction assembly is configured to be received at least partially by a recess of the cartridge such that a plane defining the planar induction element is parallel to and offset from a planar surface of the susceptor in a direction perpendicular to the plane.
In some examples in accordance with the second aspect, the planar induction element comprises one of a flat spiral coil, and one or more conductive layers deposited upon a support.
In some examples in accordance with the second aspect, the induction assembly comprises a ferrite shield, wherein at least a portion of the ferrite shield is provided parallel and adjacent to the plane of the planar induction element, wherein the ferrite shield is positioned on an opposite side of the planar induction element to the planar surface of the susceptor when the planar induction element is received in the recess of the cartridge.
According to a third aspect of certain embodiments there is provided a control unit for use in an aerosol delivery system for generating an aerosol from an aerosol-generating substrate, the control unit comprising: an induction assembly in accordance with the second aspect, a power supply for supplying power to the planar induction element, and control circuitry for controlling the supply of power to the planar induction element, wherein the control circuitry is configured to drive the planar induction element to induce current flow in a susceptor to inductively heat the susceptor and so vaporise a portion of the aerosol generating substrate in the vicinity of the susceptor.
According to a fourth aspect of certain embodiments there is provided an aerosol delivery system for generating an aerosol from an aerosol generating substrate, the aerosol delivery system comprising: a cartridge in accordance with the first aspect; and a control unit in accordance with the third aspect.
According to a fifth aspect of certain embodiments there is provided an method of generating an aerosol from an aerosol generating substrate in an aerosol delivery system, such as an aerosol delivery system in accordance with the fourth aspect, the aerosol delivery system comprising a cartridge and a control unit, wherein the cartridge comprises a susceptor and a recess, and the control unit comprises a planar induction element, a power supply and control circuitry, the method comprising: inserting the planar induction element into the recess to position a planar surface of the susceptor to be parallel to a plane defining the planar induction element and offset from the planar induction element in a direction perpendicular to the plane, and driving the planar induction element to induce current flow in the susceptor to inductively heat the susceptor and so vaporise a portion of the aerosol generating substrate in the vicinity of the susceptor.
These and further aspects of the certain embodiments are set out in the appended independent and dependent claims, and also in the clauses provided at the end of this specification. It will be appreciated that features of the dependent claims may be combined with each other and features of the independent claims in combinations other than those explicitly set out in the claims. Furthermore, the approach described herein is not restricted to specific embodiments such as set out below, but includes and contemplates any appropriate combinations of features presented herein, including combinations of the independent and dependent claims with features present in the clauses provided at the end of this specification. For example, a heater for a vapour provision system or a vapour provision system comprising a heater may be provided in accordance with approaches described herein which includes any one or more of the various features described below as appropriate.

Brief Description of the Drawings

Various embodiments of the invention will now be described in detail by way of example only with reference to the following drawings in which:

Figure 1 shows a schematic diagram of an example aerosol/vapour delivery system in accordance with aspects of the present disclosure;
Figure 2 is a schematic diagram of an example support structure of an induction assembly in accordance with aspects of the present disclosure;
Figure 3 shows an exploded view of an example cartridge in accordance with aspects of the present disclosure;
Figure 4 shows an exploded view of a further example cartridge in accordance with aspects of the present disclosure;
Figure 5 shows a schematic diagram of an example cartridge and induction assembly in accordance with aspects of the present disclosure;
Figure 6 shows a schematic diagram of a further example cartridge and induction assembly in accordance with aspects of the present disclosure;
Figure 7 shows a cross-sectional view of an example cartridge in accordance with aspects of the present disclosure;
Figure 8 shows a schematic diagram of a further example cartridge and induction assembly in accordance with aspects of the present disclosure;
Figure 9 shows a schematic diagram of a further example cartridge and induction assembly in accordance with aspects of the present disclosure; and
Figure 10 shows flow diagram depicting a method of generating an aerosol from an aerosol generating substrate in an aerosol delivery system in accordance with the present disclosure.

Detailed Description

Aspects and features of certain examples and embodiments are discussed / described herein. Some aspects and features of certain examples and embodiments may be implemented conventionally and these are not discussed / described in detail in the interests of brevity. It will thus be appreciated that aspects and features of apparatus and methods discussed herein which are not described in detail may be implemented in accordance with any conventional techniques for implementing such aspects and features.
In accordance with the present disclosure there is described a cartridge for use in an aerosol delivery system for generating an aerosol from an aerosol-generating substrate, the cartridge for use with an induction assembly, the cartridge comprising: a recess configured to receive a planar induction element; and a susceptor comprising a planar surface positioned to be parallel to a plane defining the planar induction element and offset from the planar induction element in a direction perpendicular to the plane when the planar induction element is received in the recess.
The provision of such a cartridge may be advantageous in that the cartridge configuration provides a relatively simple design which allows for efficient heating of the planar surface of the susceptor as a result of the relative alignment and positioning of the planar surface with respect to the plane of the planar induction element, due to the relatively increased magnetic flux density extending perpendicular to the plane of the planar induction element in contrast to the magnetic flux extending parallel to the plane of the planar induction element. Furthermore, in accordance with some examples, a second surface of the susceptor can be provided parallel to the plane defining the planar induction element and offset from the planar induction element in the direction perpendicular to the plane on the opposite side of the planar induction element to the (first) planar surface, in order to increase the surface area of the susceptor which is optimally heated (i.e. the surface area provided directly in line with planar induction element, and not laterally offset). Hence, aspects of the present disclosure describe a relatively simple design which allow for efficient heating.
As used herein, the term "delivery system" is intended to encompass systems that deliver at least one substance to a user, and includes non-combustible aerosol provision systems that release compounds from an aerosol-generating material without combusting the aerosol-generating material, such as electronic cigarettes, tobacco heating products, and hybrid systems to generate aerosol using a combination of aerosol-generating materials; and
According to the present disclosure, a "non-combustible" aerosol provision system is one where a constituent aerosol-generating material of the aerosol provision system (or component thereof) is not combusted or burned in order to facilitate delivery of at least one substance to a user.
In some embodiments, the delivery system is a non-combustible aerosol provision system, such as a powered non-combustible aerosol provision system.
In some embodiments, the non-combustible aerosol provision system is an electronic cigarette, also known as a vaping device or electronic nicotine delivery system (END), although it is noted that the presence of nicotine in the aerosol-generating material is not a requirement.
In some embodiments, the non-combustible aerosol provision system is an aerosol-generating material heating system, also known as a heat-not-burn system. An example of such a system is a tobacco heating system.
In some embodiments, the non-combustible aerosol provision system is a hybrid system to generate aerosol using a combination of aerosol-generating materials, one or a plurality of which may be heated. Each of the aerosol-generating materials may be, for example, in the form of a solid, liquid or gel and may or may not contain nicotine. In some embodiments, the hybrid system comprises a liquid or gel aerosol-generating material and a solid aerosol-generating material. The solid aerosol-generating material may comprise, for example, tobacco or a non-tobacco product.
Typically, the non-combustible aerosol provision system may comprise a non-combustible aerosol provision device and a consumable for use with the non-combustible aerosol provision device.
In some embodiments, the disclosure relates to consumables comprising aerosol-generating material and configured to be used with non-combustible aerosol provision devices. These consumables are sometimes referred to as articles throughout the disclosure.
In some embodiments, the non-combustible aerosol provision system, such as a non-combustible aerosol provision device thereof, may comprise a power source and a controller. The power source may, for example, be an electric power source.
In some embodiments, the non-combustible aerosol provision system may comprise an area for receiving the consumable, an aerosol generator, an aerosol generation area, a housing, a mouthpiece, a filter and/or an aerosol-modifying agent.
In some embodiments, the consumable for use with the non-combustible aerosol provision device may comprise aerosol-generating material, an aerosol-generating material storage area, an aerosol-generating material transfer component, an aerosol generator, an aerosol generation area, a housing, a wrapper, a filter, a mouthpiece, and/or an aerosol-modifying agent.
In some embodiments, the substance to be delivered may be an aerosol-generating material or a material that is not intended to be aerosolised. As appropriate, either material may comprise one or more active constituents, one or more flavours, one or more aerosol-former materials, and/or one or more other functional materials.
In some embodiments, the substance to be delivered comprises an active substance.
The active substance as used herein may be a physiologically active material, which is a material intended to achieve or enhance a physiological response. The active substance may for example be selected from nutraceuticals, nootropics, psychoactives. The active substance may be naturally occurring or synthetically obtained. The active substance may comprise for example nicotine, caffeine, taurine, theine, vitamins such as B6 or B12 or C, melatonin, cannabinoids, or constituents, derivatives, or combinations thereof. The active substance may comprise one or more constituents, derivatives or extracts of tobacco, cannabis or another botanical.
In one embodiment the active substance is a legally permissible recreational drug.
In some embodiments, the active substance comprises nicotine. In some embodiments, the active substance comprises caffeine, melatonin or vitamin B12.
As noted herein, the active substance may comprise one or more constituents, derivatives or extracts of cannabis, such as one or more cannabinoids or terpenes.
The active substance may be CBD or a derivative thereof.
As noted herein, the active substance may comprise or be derived from one or more botanicals or constituents, derivatives or extracts thereof. As used herein, the term "botanical" includes any material derived from plants including, but not limited to, extracts, leaves, bark, fibres, stems, roots, seeds, flowers, fruits, pollen, husk, shells or the like. Alternatively, the material may comprise an active compound naturally existing in a botanical, obtained synthetically. The material may be in the form of liquid, gas, solid, powder, dust, crushed particles, granules, pellets, shreds, strips, sheets, or the like.
Example botanicals are tobacco, eucalyptus, star anise, hemp, cocoa, cannabis, fennel, lemongrass, peppermint, spearmint, rooibos, chamomile, flax, ginger, ginkgo biloba, hazel, hibiscus, laurel, licorice (liquorice), matcha, mate, orange skin, papaya, rose, sage, tea such as green tea or black tea, thyme, clove, cinnamon, coffee, aniseed (anise), basil, bay leaves, cardamom, coriander, cumin, nutmeg, oregano, paprika, rosemary, saffron, lavender, lemon peel, mint, juniper, elderflower, vanilla, wintergreen, beefsteak plant, curcuma, turmeric, sandalwood, cilantro, bergamot, orange blossom, myrtle, cassis, valerian, pimento, mace, damien, marjoram, olive, lemon balm, lemon basil, chive, carvi, verbena, tarragon, geranium, mulberry, ginseng, theanine, theacrine, maca, ashwagandha, damiana, guarana, chlorophyll, baobab or any combination thereof. The mint may be chosen from the following mint varieties: Mentha Arventis, Mentha c.v.,Mentha niliaca, Mentha piperita, Mentha piperita citrata c.v.,Mentha piperita c.v, Mentha spicata crispa, Mentha cardifolia, Memtha longifolia, Mentha suaveolens variegata, Mentha pulegium, Mentha spicata c.v. and Mentha suaveolens
In some embodiments, the active substance comprises or is derived from one or more botanicals or constituents, derivatives or extracts thereof and the botanical is tobacco.
In some embodiments, the active substance comprises or derived from one or more botanicals or constituents, derivatives or extracts thereof and the botanical is selected from eucalyptus, star anise, cocoa and hemp.
In some embodiments, the active substance comprises or derived from one or more botanicals or constituents, derivatives or extracts thereof and the botanical is selected from rooibos and fennel.
In some embodiments, the substance to be delivered comprises a flavour.
As used herein, the terms "flavour" and "flavourant" refer to materials which, where local regulations permit, may be used to create a desired taste, aroma or other somatosensorial sensation in a product for adult consumers. They may include naturally occurring flavour materials, botanicals, extracts of botanicals, synthetically obtained materials, or combinations thereof (e.g., tobacco, cannabis, licorice (liquorice), hydrangea, eugenol, Japanese white bark magnolia leaf, chamomile, fenugreek, clove, maple, matcha, menthol, Japanese mint, aniseed (anise), cinnamon, turmeric, Indian spices, Asian spices, herb, wintergreen, cherry, berry, red berry, cranberry, peach, apple, orange, mango, clementine, lemon, lime, tropical fruit, papaya, rhubarb, grape, durian, dragon fruit, cucumber, blueberry, mulberry, citrus fruits, Drambuie, bourbon, scotch, whiskey, gin, tequila, rum, spearmint, peppermint, lavender, aloe vera, cardamom, celery, cascarilla, nutmeg, sandalwood, bergamot, geranium, khat, naswar, betel, shisha, pine, honey essence, rose oil, vanilla, lemon oil, orange oil, orange blossom, cherry blossom, cassia, caraway, cognac, jasmine, ylang-ylang, sage, fennel, wasabi, piment, ginger, coriander, coffee, hemp, a mint oil from any species of the genus Mentha, eucalyptus, star anise, cocoa, lemongrass, rooibos, flax, ginkgo biloba, hazel, hibiscus, laurel, mate, orange skin, rose, tea such as green tea or black tea, thyme, juniper, elderflower, basil, bay leaves, cumin, oregano, paprika, rosemary, saffron, lemon peel, mint, beefsteak plant, curcuma, cilantro, myrtle, cassis, valerian, pimento, mace, damien, marjoram, olive, lemon balm, lemon basil, chive, carvi, verbena, tarragon, limonene, thymol, camphene), flavour enhancers, bitterness receptor site blockers, sensorial receptor site activators or stimulators, sugars and/or sugar substitutes (e.g., sucralose, acesulfame potassium, aspartame, saccharine, cyclamates, lactose, sucrose, glucose, fructose, sorbitol, or mannitol), and other additives such as charcoal, chlorophyll, minerals, botanicals, or breath freshening agents. They may be imitation, synthetic or natural ingredients or blends thereof. They may be in any suitable form, for example, liquid such as an oil, solid such as a powder, or gas.
In some embodiments, the flavour comprises menthol, spearmint and/or peppermint. In some embodiments, the flavour comprises flavour components of cucumber, blueberry, citrus fruits and/or redberry. In some embodiments, the flavour comprises eugenol. In some embodiments, the flavour comprises flavour components extracted from tobacco. In some embodiments, the flavour comprises flavour components extracted from cannabis.
In some embodiments, the flavour may comprise a sensate, which is intended to achieve a somatosensorial sensation which are usually chemically induced and perceived by the stimulation of the fifth cranial nerve (trigeminal nerve), in addition to or in place of aroma or taste nerves, and these may include agents providing heating, cooling, tingling, numbing effect. A suitable heat effect agent may be, but is not limited to, vanillyl ethyl ether and a suitable cooling agent may be, but not limited to eucolyptol, WS-3.
Aerosol-generating material is a material that is capable of generating aerosol, for example when heated, irradiated or energized in any other way. Aerosol-generating material may, for example, be in the form of a solid, liquid or gel which may or may not contain an active substance and/or flavourants. In some embodiments, the aerosol-generating material may comprise an "amorphous solid", which may alternatively be referred to as a "monolithic solid" (i.e. non-fibrous). In some embodiments, the amorphous solid may be a dried gel. The amorphous solid is a solid material that may retain some fluid, such as liquid, within it. In some embodiments, the aerosol-generating material may for example comprise from about 50wt%, 60wt% or 70wt% of amorphous solid, to about 90wt%, 95wt% or 100wt% of amorphous solid.
The aerosol-generating material may comprise one or more active substances and/or flavours, one or more aerosol-former materials, and optionally one or more other functional material.
The aerosol-former material may comprise one or more constituents capable of forming an aerosol. In some embodiments, the aerosol-former material may comprise one or more of glycerol, propylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, 1,3-butylene glycol, erythritol, meso-Erythritol, ethyl vanillate, ethyl laurate, a diethyl suberate, triethyl citrate, triacetin, a diacetin mixture, benzyl benzoate, benzyl phenyl acetate, tributyrin, lauryl acetate, lauric acid, myristic acid, and propylene carbonate.
The one or more other functional materials may comprise one or more of pH regulators, colouring agents, preservatives, binders, fillers, stabilizers, and/or antioxidants.
A consumable is an article comprising or consisting of aerosol-generating material, part or all of which is intended to be consumed during use by a user. A consumable may comprise one or more other components, such as an aerosol-generating material storage area, an aerosol-generating material transfer component, an aerosol generation area, a housing, a wrapper, a mouthpiece, a filter and/or an aerosol-modifying agent. A consumable may also comprise an aerosol generator, such as a heater, that emits heat to cause the aerosol-generating material to generate aerosol in use. The heater may comprise a susceptor.
A susceptor is a material that is heatable by penetration with a varying magnetic field, such as an alternating magnetic field. The susceptor may be an electrically-conductive material, so that penetration thereof with a varying magnetic field causes induction heating of the heating material. The heating material may be magnetic material, so that penetration thereof with a varying magnetic field causes magnetic hysteresis heating of the heating material. The susceptor may be both electrically-conductive and magnetic, so that the susceptor is heatable by both heating mechanisms. The device that is configured to generate the varying magnetic field is referred to as a magnetic field generator, herein.
An aerosol-modifying agent is a substance, typically located downstream of the aerosol generation area, that is configured to modify the aerosol generated, for example by changing the taste, flavour, acidity or another characteristic of the aerosol. The aerosol-modifying agent may be provided in an aerosol-modifying agent release component, that is operable to selectively release the aerosol-modifying agent
The aerosol-modifying agent may, for example, be an additive or a sorbent. The aerosol-modifying agent may, for example, comprise one or more of a flavourant, a colourant, water, and a carbon adsorbent. The aerosol-modifying agent may, for example, be a solid, a liquid, or a gel. The aerosol-modifying agent may be in powder, thread or granule form. The aerosol-modifying agent may be free from filtration material.
An aerosol generator is an apparatus configured to cause aerosol to be generated from the aerosol-generating material. In some embodiments, the aerosol generator is a heater configured to subject the aerosol-generating material to heat energy, so as to release one or more volatiles from the aerosol-generating material to form an aerosol.
Figure 1 is a highly schematic diagram (not to scale) of an example aerosol/vapour delivery system 10 in accordance with the present disclosure. The system 10 has a generally elongate shape in this example, extending along a longitudinal axis, and comprises two main components, namely a control or power component, section or unit 20 (sometimes also referred to as an aerosol/vapour delivery device), and a cartridge assembly or section 30 (sometimes referred to as a cartomiser or clearomiser) carrying aerosolisable substrate material and operating as a vapour-generating component.
The cartridge 30 includes a reservoir 33 containing a source liquid (sometimes called a liquid aerosol generating material) or other aerosolisable substrate material comprising a formulation such as liquid or gel from which an aerosol is to be generated, for example containing nicotine. As an example, the source liquid may comprise around 1 to 3% nicotine and 50% glycerol, with the remainder comprising roughly equal measures of water and propylene glycol, and possibly also comprising other components, such as flavourings. Nicotine-free source liquid may also be used, such as to deliver flavouring. A solid substrate (not illustrated), such as a portion of tobacco or other flavour element through which vapour generated from the liquid is passed, may also be included.
The reservoir 33 has the form of a storage tank, being a container or receptacle in which source liquid can be stored such that the liquid is free to move and flow within the confines of the tank. For a consumable cartridge, the reservoir 33 may be sealed after filling during manufacture so as to be disposable after the source liquid is consumed, otherwise, it may have an inlet port or other opening through which new source liquid can be added by the user. In some examples, the cartridge 30 also comprises a susceptor 34 (sometimes called a heater, a susceptor heater or a susceptor heating element) for generating the aerosol by vaporisation of the source liquid stored in the reservoir tank 33. The susceptor 34 is intended for heating via induction, which will be described further below.
A liquid transfer or delivery arrangement (sometimes called a liquid transport element or liquid delivery element) such as a wick or other porous element 35 may be provided to deliver source liquid from the reservoir 33 to the heater 34. A wick 5 may have one or more parts located inside the reservoir 33, or otherwise be in fluid communication with the liquid in the reservoir 33, so as to be able to absorb source liquid and transfer it by wicking or capillary action to other parts of the wick 35 that are adjacent or in contact with the heater 34. This liquid is thereby heated and vaporised, to be replaced by new source liquid from the reservoir for transfer to the heater 34 by the wick 35. The wick may be thought of as a bridge, path or conduit between the reservoir 33 and the heater 34 that delivers or transfers liquid from the reservoir to the heater. Terms including conduit, liquid conduit, liquid transfer path, liquid delivery path, liquid transfer mechanism or element, and liquid delivery mechanism or element may all be used interchangeably herein to refer to a wick or corresponding component or structure.
A heater and wick (or similar) combination is sometimes referred to as an atomiser or atomiser assembly, and the reservoir with its source liquid plus the atomiser may be collectively referred to as an aerosol source. Other terminology may include a liquid delivery assembly or a liquid transfer assembly, where in the present context these terms may be used interchangeably to refer to a vapour-generating element (vapour generator) plus a wicking or similar component or structure (liquid transport element) that delivers or transfers liquid obtained from a reservoir to the vapour generator for vapour / aerosol generation. Various designs are possible, in which the parts may be differently arranged compared with the highly schematic representation of Figure 1.
In some examples, the wick 35 may be an entirely separate element from the heater 34. In some other examples, the heater 34 may be configured to be porous and able to perform at least part of the wicking function directly (a metallic mesh or foam, for example). For example, the susceptor heating element or heater 34 may comprise a capillary structure configured to wick a liquid aerosol generating substrate.
The vapour generating element may be an inductively heated susceptor element 34 that operates by inductive heating to heat and vapourise an aerosol generating material. In general, therefore, an atomiser can be considered as one or more elements that implement the functionality of a vapour-generating or vaporising element able to generate vapour from source liquid delivered to it, and a liquid transport or delivery element able to deliver or transport liquid from a reservoir or similar liquid store to the vapour generator by a wicking action / capillary force. An atomiser is typically housed in a cartridge component of a vapour generating system. In some designs, liquid may be dispensed from a reservoir directly onto a vapour generator with no need for a distinct wicking or capillary element. Embodiments of the disclosure are applicable to all and any such configurations which are consistent with the examples and description herein.
The liquid delivery element 35 may comprise any suitable wicking material. For example, it may be made from fibres which are grouped, bunched, wadded, woven or non-woven into a fabric or a fibrous mass, where interstices are present between adjacent fibres to provide a capillary effect for absorbency and wicking. Examples of fibre materials include cotton (including organic cotton), ceramic fibres and silica fibres. Other suitable materials are not excluded and will be apparent to the skilled person. In some examples (as an alternative to fibre based materials) the liquid delivery element 35 comprises a solid porous element, such as a porous ceramic material or a porous foam. For example, a porous ceramic material comprises a network of tiny pores or interstices which is able to support capillary action and hence provide a wicking capability to absorb liquid from a reservoir and deliver it to the vicinity of the heater for vaporisation.
Returning to Figure 1, the cartridge 30 comprises a housing 36 defining a mouthpiece or mouthpiece portion having an opening or air outlet 12 through which a user may inhale the aerosol generated by the susceptor 34. In these examples, the outer surface of the housing 36 may be shaped to accommodate a user's lips to enable a user to more easily form a seal around the air outlet 12 with their mouth. In other examples (not shown), the cartridge 30 may not include or otherwise define a mouthpiece. Instead, in some examples, a mouthpiece may connect to the cartridge 30, or the cartridge 30 may be received within a cavity of the control unit 20 such that the cartridge 30 is entirely enclosed by the control unit 20 which itself provides or is attached to a mouthpiece.
The power component or control unit 20 (sometimes called a device or device part) includes a power supply 25, such as a cell or battery, and which may be re-chargeable, to provide power for electrical components of the system 10, in particular to apply power to an induction element or work coil 42 (described in more detail below) to inductively heat the susceptor 34.
Additionally, there is a controller 28 such as a printed circuit board and/or other electronics or circuitry for generally controlling the aerosol delivery system 10. The control electronics / circuitry 28 operates the induction element 42 using power from the power supply 25 when vapour is required, for example in response to a signal indicative of a user pressing a button (not shown) or from an air pressure sensor or air flow sensor (not shown) that detects an inhalation on the system 10 during which air enters through one or more air inlets 14 (e.g. provided at a junction between the control unit 20 and the cartridge 30).
When the induction element 42 is operated, the induction element 42 inductively heats the susceptor 34 to a suitable temperature in order to vaporise source liquid delivered from the reservoir 33 by the liquid delivery element 35 to generate the aerosol, and this is then inhaled by a user through the opening 12 in the mouthpiece of the cartridge housing 36. The aerosol is carried from the aerosol source to the mouthpiece outlet 12 along one or more air channels defining an air pathway 16 (for example, see the arrows depicted in Figure 1) that connect the air inlet 14 to the aerosol source to the air outlet when a user inhales on the air outlet 12.
In some examples, the control unit 20 comprises a frame, or support structure 22 (sometimes called a device frame or support) which is configured to support, retain or position various components of the control unit 20, including the power supply 25 and the control circuitry 28. The frame 22 may also support other components not shown such as a wired connection port and PCB for charging (and optionally, communication), user interface elements (e.g. buttons, LEDs, display screens, haptic feedback units), and / or wireless communication components. The frame 20 can be provided by a single component, or may comprise a number of frame components which are combined to form the frame 20.
In some examples, the control unit 20 comprises an outer housing 24 and / or an end cap 26. For example, the outer housing 24 may be a tubular structure or wrap, which is configured to contain the components of the control unit 20. For example, the frame 22 containing the power supply 25 and the control circuitry 28 can be inserted into the outer housing 24, or the outer housing 24 can be provided around the outside of the frame 22. In some examples, an end cap 26 is provided at one end of the outer housing 24 (e.g. after insertion of the frame 20 containing the power supply 25 and the control circuitry 28) to seal the outer housing 24 (e.g. to protect the components on the inside of the outer housing 24 from the ingress of water and dust).
The induction element or work coil 42 may be provided as part of an induction assembly 40 which comprises a support structure or housing 44 which is configured to position or contain the induction element or work coil 42 (i.e. the support structure 44 supports the induction element 42). In some examples, the induction assembly 40 is formed by integrally molding the support structure 44 around the inductive work element 42, whereas in other examples the support structure 44 provides a scaffolding to which the inductive work element is attached or fixed.
In some examples, the induction assembly 40 comprises a ferrite shield (not shown), such as a film, foil or sheet, which may be retained in position by the support structure 44. For example, the ferrite shield may be inserted or embedded into the support structure 44, or wrapped around an outer surface of the support structure 44. A ferrite shield can be used to inhibit magnetic flux in the direction of the shield from the induction element 42, when power is supplied to the induction element 42.
In some examples, the induction assembly 40 is a fixed or permanent component of the control unit 20. For example, the support structure 44 can be integrally formed with the frame 22 of the control unit 20. In other examples, the induction assembly 40 and the control unit 20 are separate connectable parts detachable from one another by separation in a direction parallel to the longitudinal axis of aerosol delivery system 10. For example, the components 20, 40 are joined together when the system 10 is in use by cooperating engagement elements (for example, a screw or bayonet fitting) which provide mechanical and electrical connectivity between the power section 20 and the induction assembly 40. The electrical connectivity can be required in order to provide electrical power to the induction element 42 when the control circuitry 28 determines that power should be supplied to the induction element 42.
The use of an interchangeable induction assembly 40 improves the ease of replacing the induction assembly 40 in the case of damage or wear, as well as potentially also allowing for customisation of a system 10 by allowing a user to replace an induction assembly with a different induction assembly with an alternate configuration for operation with a different susceptor 34 arrangement (e.g. provided by a cartridge 30 having a different configuration).
In some examples, the induction assembly 40 may seal an end of the outer housing 24 (e.g. to protect the components on the inside of the outer housing 24 from the ingress of water and dust). For example, the induction assembly 40 may be provided at the opposite end of the outer housing 24 to the end having the end cap 26. The induction assembly 40 may connect to the frame 22 and / or the outer housing 24 in such a way that a liquid seal is formed preventing liquid from flowing into the cavity formed by the outer housing 24, end cap 26 and the induction assembly 40. Alternatively in some examples, the control unit comprises a second end cap which is fixed to the outer housing 24 and / or frame 22 between the frame 22 and the induction assembly 40. In some of these examples, a second end cap may be configured to facilitate the attachment of the induction assembly 40 to the control unit 20.
The control unit (power section) 20 and the cartridge (cartridge assembly) 30 are separate connectable parts detachable from one another by separation in a direction parallel to the longitudinal axis of aerosol delivery system 10. In some examples, the components 20, 30 are joined together when the system 10 is in use by cooperating engagement elements (for example, a screw or bayonet fitting) which provide mechanical connectivity (and in some examples electrical connectivity) between the power section 20 and the cartridge assembly 30. For example, a portion of the outer housing 24 can be an engagement element (not shown) configured to engage with a corresponding engagement (not shown) of the cartridge 30 provided by a portion of the cartridge housing 36.
In some other examples, the induction assembly 40 may facilitate the connection between the control unit 20 and the cartridge 30. For example the induction assembly 40 and the cartridge 30 may include cooperating engagement elements (for example, a screw or bayonet fitting) which provide mechanical (and optionally electrical) connectivity between the induction assembly 40 and the cartridge 30 to indirectly connect the cartridge 30 to the control unit 20 (including electrical connectivity if necessary) via the induction assembly 40.
In systems that use inductive heating, electrical connectivity can be omitted from the connection between the cartridge 30 and the control unit 20 if no parts requiring electrical power are located in the cartridge 30.
In some examples, the cartridge 30 and induction assembly 40 are shaped (e.g. the cartridge housing 36 and the induction support 44, respectively) so that when they are connected, there is an appropriate exposure of the susceptor 34 to flux generated by the induction element 42 for the purpose of generating current flow in the material of the heater. For example, a portion of the cartridge 30 containing the susceptor 34 may be provided adjacent a portion of the induction assembly 40 proximal to the induction element 42. Inductive heating arrangements are discussed further below.
As described above, aspects of the disclosure relate to inductive heating. This is a process by which an electrically conducting item, typically made from metal, is heated by electromagnetic induction via eddy currents flowing in the item which generates heat. An induction element 42 (e.g. work coil) operates as an electromagnet when a high-frequency alternating current from an oscillator is passed through it; this produces a magnetic field. When the conducting item (i.e. susceptor 34) is placed in the flux of the magnetic field, the field penetrates the item and induces electric eddy currents. These flow in the item, and generate heat according to current flow against the electrical resistance of the item via Joule heating, in the same manner as heat is produced in a resistive electrical heating element by the direct supply of current.
An attractive feature of induction heating is that no electrical connection to the conducting item is needed; the requirement instead is that a sufficient magnetic flux density is created in the region occupied by the item. In the context of vapour provision systems, where heat generation is required in the vicinity of liquid, this is beneficial since a more effective separation of liquid and electrical current can be effected. Assuming no other electrically powered items are placed in a cartomiser, there is no need for any electrical connection between a cartridge and its power section, and a more effective liquid barrier can be provided by the cartomiser wall, reducing the likelihood of leakage.
Induction heating is effective for the direct heating of an electrically conductive item, as described above, but can also be used to indirectly heat non-conducting items. In a vapour provision system, the need is to provide heat to liquid in the porous wicking part of the atomiser in order to cause vaporisation. For indirect heating via induction, the electrically conducting item is placed adjacent to or in contact with the item in which heating is required, and between the work coil and the item to be heated. The work coil heats the conducting item directly by induction heating, and heat is transferred by thermal radiation or thermal conduction to the non-conducting item. In this arrangement, the conducting item is termed a susceptor. Hence, in an atomiser, the heating component can be provided by an electrically conductive material (typically metal) which is used as an induction susceptor to transfer heat energy to a liquid proximal to the atomiser (e.g. held by a wick 35 and / or the susceptor 34 itself).
The susceptor 34 (sometimes called heater or susceptor heating element) may usefully be formed from a suitable material, which is electrically resistive/conductive, in other words able to carry an electrical current. This enables the heater to have its temperature increased by exposure to a magnetic field generated by a high frequency alternating current in a work coil, by induction effects as noted above, where the magnetic flux induces eddy currents in the heater material.
In some examples, the susceptor 34 comprises a planar element such as a sheet of an appropriate material, suitably dimensioned and shaped for making into a heater. A planar element such as a sheet inherently provides a (first) planar surface on one face of the planar element and a second planar surface on the opposing side of the planar element. In some examples, at least a portion of the planar element may be positioned to be offset from, and parallel to, a plane of the induction element (e.g. they each provide a parallel plane of a pair of parallel, adjacent, planes). The portion of the planar element forming the susceptor 34 which is offset from, and parallel to, a plane of the induction element 42 will be exposed to the magnetic field generated by the high frequency alternating current in the induction element 42. Without being bound by theory, this field will typically be strongest towards the centre of the plane of the induction element 42 for a spirally wound two-dimensional coil. Hence, the portion of the susceptor 34 which is offset and parallel to the plane of the induction element 42 will be heated more relative to portions of the susceptor 34 which are additionally or alternatively offset or displaced laterally with respect to the plane of the induction element 42.
In some examples, the susceptor 34 formed from a planar element such as a sheet may be curved or bent into a non-flat shape (the susceptor 34 no longer occupies a single plane). The curving may be formed by rolling or folding. In some examples, by curving or bending the susceptor 34, the susceptor 34 is configured to provide a first planar surface on one side of the plane of the induction element 42 and a second planar surface on an opposing side of the induction element 42, the two portions of the susceptor 34 providing the first and second planar surfaces being connected by the curved or bent portion. In some examples, by curving or bending the susceptor 34, the first planar surface (and / or second planar surface) may be provided in the form of a substantially flat surface (rather than a flat surface) which comprises a curvature taking the planar surface out of a single plane. Said surfaces are considered substantially planar surfaces because the curvature of the planar surface is relatively small. For example, the curvature of the surface may be up to 10 degrees with respect to an abstract origin of a circle located on the opposing side of the plane of the induction element 42 to the susceptor 34 (in contrast to the separation of the susceptor and the planar element which may be in the range of up to 2 mm; the separation of the susceptor and the abstract origin may be in the range of a few cm or more, such that the surface of the susceptor is substantially planar with respect to the plane of the induction element).
A suitable element for a heater 34 (susceptor) is to be made from an electrically conductive material, with adequate resistance to enable heating by induction effects via induced eddy currents. In some examples, the susceptor 34 is provided by a planar element such as a sheet. For example, the susceptor 34 is a sheet of a metallic material, where suitable metals include mild steel, ferritic stainless steel, aluminium, nickel, cupro-nickel, nichrome (nickel chrome alloy), and alloys of these materials. In some examples, the sheet may be laminate of layers of two or more materials. The sheet thickness can be balanced against the requirement to provide a sufficient volume of resistive material to provide sufficient heating (recalling that in some examples the amount of material is reduced by perforations). Accordingly, the thickness of the planar element (e.g. the sheet providing the susceptor) may be in the range of about 20 µm to about 70 µm, for example about 30 µm to about 60 µm, or about 40 µm to about 55 µm. In some examples, the susceptor 34 comprises a sheet (providing one or both of the first and second planar surfaces), where a (first) thickness of a (first) sheet is in the range of one or more of 20 µm to 70 µm, 30 µm to 60 µm, and 40 µm to 55 µm. These values may be the total thickness of the sheet including any supporting elements or coatings. If the thickness is insufficient, the heater may lack adequate structural integrity, although this may be compensated by additional components (e.g. support components).
In some examples, where the susceptor 34 additionally comprises a second planar surface provided by a second sheet (e.g. on an opposite side of the induction element 42 to the first planar surface), a first thickness of the first sheet is in the range of one or more of 20 µm to 70 µm, 30 µm to 60 µm, and 40 µm to 55 µm, and / or a second thickness of the second sheet is in the range of one or more of 20 µm to 70 µm, 30 µm to 60 µm, and 40 µm to 55 µm.
In some examples, a planar element for a heater 34 has a simple cuboid shape (e.g. providing a rectangular surface), which can optionally be manipulated into a particular configuration (e.g. by curving the surface of the shape to provide two flat planar portions connected by a curved portion). In other examples, a planar element may have an alternative shape such as a circular, or elliptical shape. This may be particularly useful where heating is intended to be focussed at particular zones or portions within the cartridge 30. In some of these examples, the planar element can be provided with a shape that corresponds to zones which are incident with relatively large magnetic flux from the planar element. In some examples, the planar element is substantially flat in that the planar element is sheet-like and provides a substantially planar surface by one face of the sheet-like element.
In some other examples, the susceptor 34 is not provided by a planar element (i.e. defined by two dimensions and a thickness of a relatively small order of magnitude) and is instead provided by an block element having a thickness of a similar order of magnitude to the two dimensions defining the planar surface of the susceptor 34; the element or block formed of a suitable electrically conductive material, with adequate resistance to enable heating by induction effects via induced eddy currents. For example, the susceptor 34 may comprise an inductively heatable material such as wire wool or mesh (e.g. a (ferritic) stainless steel mesh) or a metal foam (e.g. nickel foam or cupro-nickel foam) formed into an appropriate shape. In contrast to a planar element, a block (e.g. provided by stainless steel mesh or nickel foam) may have a thickness in the range of 0.1 to 3 mm. In some examples, the stainless steel mesh or nickel foam may have a thickness in the range of 0.2 to 1 mm. In some examples, the stainless steel mesh or nickel foam may have a thickness in the range of 0.25 to 0.6 mm.
In some examples, a block element for a heater 34 has a simple cuboid shape. In some examples, a block can be formed into a particular configuration (e.g. by curving the surface of the shape). In other examples, a block element may have an alternative shape such as a circular or elliptical disc shape with a thickness as described above. This may be particularly useful where heating is intended to be focussed at particular zones or portions within the cartridge 30. In some of these examples, the block element can be configured with a shape that corresponds to zones which are incident with relatively large magnetic flux from the planar element. A suitable block element provides a substantially planar surface by one face of the block element (e.g. a surface providing a surface of the recess adjacent to the induction element 42). In some examples, a suitable block element may be formed by pressing a steel mesh into a required shape or by forming a nickel foam within a mould having a required shape.
In some examples, the susceptor heating element 34 (sometimes called the susceptor 34 or heater 34) comprises a plurality of apertures extending through the susceptor heating element 34. Said apertures may be called perforations or holes. In some examples, the plurality of perforations may be holes cut or punched through the material of a susceptor 34 formed from a planar element (e.g. a sheet of material). Each hole is small compared to the area of the planar element. In some examples, the holes are relatively closely packed and evenly distributed over the planar element so that many holes are included. The holes may be circular, for example, or may be elongated or slot-shaped. The purpose of the holes is to enable the generated vapour to more easily escape from the atomiser into the aerosol chamber to be collected by the airflow through the aerosol chamber. For example, when liquid in the wick 35 within the atomiser is vaporised by the heat from the heater 34, the generated vapour can flow outwardly through the perforations into the free space of the air pathway 16 adjacent to the heater 34.
When designing the heater 34, it may be necessary to balance the increased ease of vapour flow afforded by additional perforations with the decreased amount of heater material available for heating. Accordingly, one can consider an optimum total area for the perforations compared to the area of the heater material which generates heat and provides it for vaporisation. If we define the total heater material area without any holes, a range for the total area then taken up the perforations may be in the range of about 5% to 30%, for example about 20% of the total heater material area, for example. In any case, it is useful that the total area of the perforations does not exceed about 50%, due to manufacturing restrictions. Also, too large an open area (total area of the perforations) may lead to poor inductive coupling in the event that induction heating is used, while too small an open area makes it difficult for generated vapour to escape from the wick 35.
In some examples, the plurality of apertures or perforations are arranged in a pattern, with the density of the plurality of apertures varying from a peripheral edge of the planar surface of the susceptor heating element 34 towards a centre of the planar surface of the susceptor heating element. In some examples, the density of the plurality of apertures increases from a peripheral edge of the planar surface of the susceptor heating element 34 towards a centre of the planar surface of the susceptor heating element 34.
In some examples, the wick 35 comprises an inductively heatable material such as a stainless steel mesh or a nickel foam. Said wick 35 formed of an inductively heatable material may also provide the heater 34 component (e.g. a combined wick-heater atomiser) or may be in addition to the heater 34 (e.g. the wick part of an atomiser formed of a wick 35 and heater 34). When the wick 35 is placed in the flux of the magnetic field, the field penetrates the item and induces electric eddy currents. These flow in the item, and generate heat according to current flow against the electrical resistance of the item via Joule heating, in the same manner as heat is produced in a resistive electrical heating element by the direct supply of current. In some examples, particularly where the wick 35 is used in conjunction with a separate susceptor 34, the wick 35 is able to contribute to the heating of the liquid and may also retain residual or latent heat between puffs, which can act to reduce the amount of energy or time required to heat the susceptor 34 to a vaporisation temperature on a subsequent puff. In particular, the wick 35 may have a large mass, in comparison to the susceptor 34, which acts to store latent heat, while the relatively low mass of the susceptor 34 allows for rapid heating of the susceptor 34.
In some examples, a stainless steel mesh or nickel foam has a simple rectangular shape, which can optionally be manipulated into a particular configuration (e.g. by curving the surface of the shape). In other examples, a planar element may have an alternative shape such as a circular, or elliptical shape. This may be particularly useful where heating is intended to be focussed at particular zones or portions within the cartridge 30. In some of these examples, the planar element can be provided with a shape that corresponds to zones which are incident with relatively large magnetic flux from the planar element. In some examples, the planar element is substantially flat in that the planar element is sheet-like and provides a substantially planar surface by one face of the sheet-like element.
Returning to Figure 1 in more detail, in the example shown, the cartridge 30 and induction assembly 40 are shaped so that a portion of the induction assembly 40 containing the induction element 42 is received within a cavity or void of the cartridge 30 when the cartridge 30 and induction assembly 40 are connected. In particular, in examples in accordance with Figure 1, the induction element 42 is provided in the form of a planar induction element, the induction could being formed substantially in a plane around an axis. In examples such as those in accordance with Figure 1, the axis around which the planar induction element is formed is perpendicular to the longitudinal axis of the system 10.
In some examples, the planar induction element 42 is formed by a resistive wire, such as a nickel or cupronickel wire, which is configured or arranged into a shape such as a spiral. In some examples, a resistive wire providing the planar induction element 42 is provided in a support 44 which acts to retain the resistive wire in a particular shape (e.g. a two-dimensional spiral). In some of these examples, the resistive wire may be embedded in the support. In other examples, a resistive wire providing the planar induction element 42 is substantially freestanding in that the resistive wire is able to support an orientation and configuration with respect to an anchor location (i.e. where the resistive wire engages a support 44). For example, the resistive wire may be a suitably rigid material (e.g. a suitably thick wire) that it is able to maintain a configuration throughout continued use.
In some examples, the planar induction element 44 may be printed or deposited on a portion of a substrate or support 44 which is configured to be inserted into the recess 38 when the cartridge 30 is attached to the induction assembly 40 and / or device 20. In some examples, a laser is used to activate the surface of the support 44, which may comprises a thermoplastic material such as polyetheretherketone (PEEK) which may have been doped with a metallic inorganic compound. The laser creates one or more laser activated regions upon the support 42 which can then be further metallised using e.g. an electroless plating process to build up one or more conductive layers of e.g. copper. For example, an inductor coil may be deposited upon a support 44 so as to form a spiral inductor coil 42. However, other embodiments are also contemplated wherein the inductor coil 42 may be formed upon the support 44 so as to have a different configuration.
Forming a planar induction element 42 by printing or depositing a conductive layer on a support 44, such as by utilising a laser direct structuring process as described above, results in a induction element 42 being formed which is integrated with or into the support 44. This advantageously can reduce the size of the support 42 required compared to a support 42 which is suitable for retaining a resistive wire providing a planar induction element 42 and can therefore enable the induction assembly 40 to be provided in a more compact arrangement.
In some examples, the planar induction element is a planar induction coil. For example, the planar induction element is a flat spiral coil (sometimes called a pancake coil). By a flat coil it is meant that the coil spirals in a two dimensional plane from an outer most point of the spiral to an inner most point of the spiral (not necessarily at the geometric centre of the spiral). In some examples, the coil may project out of the two dimensional plane to some extent, and may be considered folded or curved. In these examples, the flat spiral coil is a substantially flat spiral coil in that the extent of any curving or folding out of the plane is relatively small, and preferably less than 5 degrees out of the plane. In other examples, the spiral coil does not project out of the two dimensional plane of the spiral configuration, other than by way of the three-dimensional thickness of the element providing the spiral coil (e.g. wire thickness or deposition thickness).
In some examples, the spiral coil increases regularly or consistently from a centremost point to an outermost point (e.g. constant radial increase per change in angle), and may be considered a substantially circular spiral coil. In some other examples, the spiral coil has a substantially elliptical shape or an irregular shape caused by, for example, varying the radial increase as a function of the change in angle and distance from the axis from a centremost point to an outermost point.
In the example of Figure 1, the portion of the induction assembly 40 containing the induction element 42 is part of the support structure 44 or housing of the induction assembly 40. This part of the support structure 44 may have a planar shape corresponding or related to the plane of the planar induction coil. The support structure 44 may be defined by first and second planar surfaces on respective sides of the planar induction coil 42 (i.e. intersecting with the axis around which the planar induction coil is formed), and also one or more peripheral surfaces radially outward from the spiral (i.e. not intersecting with the axis around which the spiral coil is formed). The support structure 44 may surround the planar induction element 42 in the to provide a protective housing for the planar induction element and / or to support or maintain the position of the planar induction element 42 within the induction assembly 40. In some other examples, not shown, at least a portion of the planar induction element 42 may not be covered by the support structure 44. In such examples, the planar induction element 42 may be exposed to ambient air.
At least a part of the susceptor 34 is provided adjacent the surface of the induction assembly 40 proximal to the induction element 42. In particular, the susceptor 34 of figure 1 comprises first and second susceptor portions. Each susceptor portion may define a planar surface which is provided parallel and adjacent to the plane of the planar induction element 42 (and parallel to a plane of the support structure 44, if present). The first and second susceptor portions are provided on opposite sides of the planar induction element 42 such that the planar induction element 42 can operate to heat both the first susceptor portion and the second susceptor portion simultaneously. By simultaneously heating both the first susceptor portion and the second susceptor portion, the total vapour production surface of the susceptor 34 is increased relative to the surface area provided by only one of the susceptor portions, which can lead to increased vapour production.
In some examples, a recess 38 is defined at least in part by a planar surface of the susceptor 34. For example, a recess 38 is formed between the first and second portion of the susceptor 34. When the cartridge 30 and the control part 20 are connected, the planar induction element 42 is at least partially inserted into the recess 38 to position the planar surface of the susceptor 34 adjacent to the planar induction element 42. In other words, the aerosol delivery system 10 comprises a second susceptor heating element, wherein the recess 38 is defined at least in part by a second planar surface of the second susceptor heating element, the planar surface of the second susceptor heating element adjacent to the planar induction element 42 such that the planar induction element 42 is between the planar surface of the susceptor heating element and the second planar surface of the second susceptor heating element.
By providing the susceptor portions parallel and adjacent to the plane of the planar induction element 42 there is an appropriate exposure of each susceptor portion to flux generated by the induction element 42 for the purpose of generating current flow in the material of the heater. In this way, the susceptor 34 is responsive to the magnetic field generated by the planar induction element 42. If the susceptor portions are located so that the separation of each portion of the susceptor from the planar induction element 42 is minimised, the flux experienced by each portion of the susceptor 34 can be higher and the heating effect made more efficient.
The distance separating the susceptor 34 (e.g. each of the respective portions of the susceptor) from the induction element 42 is sometimes called the coupling distance. Without being bound by theory, the susceptor 34 and the induction element 42 effectively form a pair in which the induction element 42 is inductively coupled to the susceptor and is able to transmit or transfer energy to the susceptor 34 when a current is applied to the induction element 42. The coupling distance relates to the distance across which energy is transferred from the induction element 42 to the susceptor. The further away the susceptor 34 is (i.e. the larger the coupling distance), the greater the loss in energy. In some examples, in order to reduce energy losses to a suitable proportion, the coupling distance is in the range of less than 2 mm. In some examples, the coupling distance is in the range of less than 1.5 mm. In some examples, the coupling distance is in the range of less than 1 mm. It will be appreciated that the relationship of different portions of the susceptor 34 to the induction element can be defined by their own coupling distance.
The coupling distance can alternatively be described by the offset distance relating to the distance separating the planar surface from the planar induction coil (e.g. the difference between abstract parallel planes relating to the planar surface and the planar induction coil). In some examples, the planar surface is offset from the planar induction element by an offset distance in a range of less than 2 mm. In some examples, the planar surface is offset from the planar induction element by an offset distance in a range of less than 1.5 mm. In some examples, the planar surface is offset from the planar induction element by an offset distance in a range of less than 1 mm.
As shown in Figure 1, in some examples, the aerosol delivery system 10 comprises an air pathway 16 defined in part by a volume between the susceptor heating element 34 and the induction assembly 40 (e.g. between a surface defined by the support 44). The separation of the susceptor 34 and the induction assembly 40 is set at least in part by the width or size of the portion of the air pathway 16 formed between the surface of the susceptor 34 and the surface of the support structure 44, with the air pathway 16 in this region of the system 10 needing to be sized to allow adequate air flow. In some examples, the separation of the susceptor 34 and the induction assembly 40 is in the range of more than 0.5 mm. In some examples, the separation of the susceptor 34 and the induction assembly 40 is in the range of more than 1 mm. The separation of the susceptor 34 and the induction assembly 40 can sometimes be called a thickness of the air pathway 16 (in contrast to a width parallel to the plane of the induction element/susceptor, and in contrast to a length in the extending towards the outlet 12).
Hence, the requirements of the aerosol pathway and the coupling distance need to be balanced against one another when determining the sizing and positioning of the various items. In some examples, the coupling distance is in the range of 0.75 mm to 2 mm, and the separation of the susceptor 34 and the induction assembly 40 (thickness of the air pathway 16) is in the range of more than 0.5 mm to 1.5 mm, where the separation of the susceptor 34 and the induction assembly 40 is less than or equal to the coupling distance. In some examples, the coupling distance may be equal or substantially equal to the separation of the susceptor 34 and the induction assembly 40. For example, there may be no further features between the susceptor 34 and the induction assembly 40 (e.g. the support 44 may not encompass the induction element 42, which instead extends from the induction element 42). In some other examples, the coupling distance may be less than the separation of the susceptor 34 and the induction assembly 40 due to the presence of a protective layer or housing layer (e.g. provided by the support 44 to protect the induction element 42).
The Figure 1 design is merely an example arrangement, and the various parts and features may be differently distributed between the power section 20 and the cartridge assembly section 30, and other components and elements may be included. The two sections may connect together end-to-end in a longitudinal configuration as in Figure 1, or in a different configuration such as a parallel, side-by-side arrangement. The system may or may not be generally cylindrical and/or have a generally longitudinal shape. Either or both sections or components may be intended to be disposed of and replaced when exhausted (the reservoir is empty or the battery is flat, for example), or be intended for multiple uses enabled by actions such as refilling the reservoir and recharging the battery. In other examples, the system 10 may be unitary, in that the parts of the control unit 20 (including the induction assembly 40) and the cartridge 30 are comprised in a single housing and cannot be separated. Embodiments and examples of the present disclosure are applicable to any of these configurations and other configurations of which the skilled person will be aware.
Figure 2 is a schematic diagram of an example support structure or housing 44 of an induction assembly 40 in accordance with the present disclosure. The example housing 44 comprise an insertion portion 45 and a base portion 46. Aspects of the support 44 (and related components for use with the support) may be as described in relation to Figure 1.
The insertion portion 45 comprises a spiral recess 47 for receiving a spiral coil. An induction assembly 40 is created by providing an suitable planar induction element 42 (i.e. a spiral coil in this example) in the spiral recess 47. It will be appreciated that in other examples, where the induction element 42 is not a spiral coil, the insertion portion 45 may have an alternative to the spiral recess 47 which is suitable for receiving the alternate induction element 42. The insertion portion 45 is configured to be inserted into a recess 38 of a cartridge 30 to position the planar induction element 42 (e.g. spiral coil) parallel and offset from a planar surface of the susceptor heating element 34 of a cartridge 30. The distance of the offset is equivalent to the coupling distance.
As per the example of Figure 2, the insertion portion 45 has a planar arrangement in that the insertion portion 45 is defined by has first and second opposing faces separated by a thickness of the insertion portion 45, and a peripheral surface extending between the first and second opposing faces in a direction parallel to the thickness of the insertion portion 45 between the first and second opposing faces. The spiral recess 47 of insertion portion 45 may extend between the first and second opposing faces as shown, or the spiral recess 47 may be internal to the housing 44 (i.e. to encapsulate an induction element 42).
In some examples, the thickness of the insertion portion 45 is selected to be equal or to approximately equal the width of the induction element 42 received in the spiral recess 47 (e.g. the diameter of a wire providing a spiral coil). By approximately equal it is meant that the thickness may be slightly less than the width of the induction element 42 (no less than 95% of the width), or slightly more than the support the width of the induction element 42 (no more than 105% of the width). In some examples, the thickness of the insertion portion 45 is selected to provide structural rigidity to the induction assembly 40 and / or support for the induction element 42.
In the example of Figure 2, the planar arrangement or configuration of the insertion portion 45 corresponds to the planar arrangement of a planar induction element 42 received in the insertion portion 45. As such, when the planar induction element 42 is inserted into the recess 38 of the cartridge 30 to position a planar surface of the susceptor heating element 34 to be parallel to a plane defining the planar induction element 42 and offset from the planar induction element 42 in a direction perpendicular to the plane; the planar surface of the susceptor heating element 34 is also parallel and offset from the plane defined by one of the opposing faces of the insertion portion 45 (with the other of the opposing faces potentially being parallel and offset from a different planar surface of the susceptor heating element 34).
The base portion 46 comprises attachment features 48 configured to facilitate the connection of the housing 44 to a control part having corresponding attachment features (i.e. the control part 20 of Figure 1). In some examples, the attachment features 48 allow an induction assembly 40 to be reversibly connected to a control part, such that the induction assembly 40 can be removed and replaced without damaging the control part or the induction assembly 40. In some other examples, where the induction assembly 40 is an integral component of a control part, the attachment features 48 may be omitted 48 (e.g. the housing 44 may be integrally formed with a housing of the control part), or the attachment features 48 may be configured to provide a permanent attachment which is not intended to be reversed (i.e. disconnected).
In the example of Figure 2, the base portion 46 further comprises a channel 49 providing a portion of the airflow pathway 16. The channel 49 may for example direct, or facilitate, air flow through the base portion and towards or across the first and / or second opposing face of the insertion portion 45. In some examples, the channel 49 may extend into a recessed void on the lower side of the base portion (opposite the insertion portion 45) which is configured to allow airflow between the base portion 46 and the control unit (e.g. a surface of a housing of a control unit as shown in Figure 1). In some examples not in accordance with Figure 2, the channel 59 can be omitted. For example, airflow may be along a top surface of the base portion 46 (adjacent and perpendicular to the insertion portion 45) prior to flowing across one or both opposing surfaces of the insertion portion 45, or the airflow pathway 16 may not be between the susceptor 34 and the induction assembly 40 (e.g. the airflow pathway 16 may be on an opposite side of a portion of the susceptor 34 to the induction assembly 40).
Figure 3 is a exploded perspective drawing of an example cartridge 30 in accordance with the present disclosure. The cartridge 30 may be for use with an induction assembly 40 comprising the support 44 of Figure 2. The cartridge 30 comprises an upper housing 361, a lower housing 362, a seal 363, a susceptor 34, and a liquid transport element 35. Various aspects of the cartridge 30 may be as described in relation to Figure 1.
The susceptor 34 of Figure 3 comprises a first portion defining a first planar surface 341 and a second portion defining second planar surface 342. By defining it is meant that the first planar surface 341 and the second planar surface 342 are surfaces of the first portion and the second portion, respectively, with the shape of the first and second portion defining the shape of the respective surfaces. The first and second planar portions of the susceptor 34 are joined by a connecting portion of material 343. For example, the susceptor 34 of Figure 3 may be formed by a continuous sheet of material (e.g. nickel, cupronickel, aluminium) forming each portion of the susceptor 34. Said continuous sheet may be considered a planar element which is curved between two flat portions which provide the first and second susceptor portions 341, 342, and the connecting portion 343 of the susceptor 34.
The recess 38 for receiving the planar induction element 42 is defined at least in part by the connecting portion 343, the first planar surface 341 and the second planar surface 342. The first planar surface 341 and the second planar surface 342 are parallel to each other, such that the recess 38 is defined by two planar, adjacent, surfaces. The connecting portion 343 additionally comprises an outlet 344 which forms part of the air pathway 16, and in particular allows fluid connection between the recess 38 and the outlet 12 of a system 10 containing a cartridge 30 in accordance with Figure 3.
The susceptor 34 of Figure 3 comprises a plurality of apertures, holes or perforations 345 extending through the susceptor heating element 34. The plurality of perforations 345 may be provided by cutting holes or piercing through the material of the susceptor 34. Each hole is small compared to the area of the susceptor. The purpose of the holes 345 is to enable the generated vapour to more easily escape through the susceptor 34 into the recess 38 (i.e. the aerosol chamber) to be collected by the airflow through the recess 38. For example, when liquid in the wick 35 is vaporised by the heat from the heater 34, the generated vapour can flow through the perforations into the free space of the air pathway 16 in the recess between the heater 34 and the induction assembly 40. In the example of Figure 3 the plurality of perforations 345 are provided in the first portion and the second portion, but not the connecting portion 343. In some other examples, not shown, the connecting portion 343 may also comprise some of the plurality of perforations 345.
The first planar surface 341 is positioned to be parallel to a plane defining the planar induction element 42 and offset from the planar induction element 42 in a direction perpendicular to the plane (of the planar induction element 42), when the planar induction element 42 is received in the recess 38 of the cartridge 30. Similarly, the second planar surface 342 is positioned to be parallel to the plane of the planar induction element 42 and offset from the planar induction element 42 in a direction perpendicular to the plane, when the planar induction element 42 is received in the recess 38, the second planar surface 342 being provided on (e.g. defining) an opposite side of the recess 38 to the first planar surface 341.
A planar induction element 42, as discussed above in relation to Figure 1 and suitable for use with a support 44 in accordance with Figure 2, is configured to generate a magnetic field that primarily (or dominantly) extends perpendicular to the plane of the planar induction element 42. As a result, the inductive heating is strongest for a susceptor which is placed in an space which is perpendicular to the plane of the planar induction element 42. Hence, the first planar surface 341 and the second planar surface 342 are provided in positions which will be optimally heated (i.e. positions which are parallel to and offset from the planar induction element 42 in a direction perpendicular to the plane of the planar induction element 42).
In some examples, both the area of the first planar surface 341 of the susceptor 34 facing the planar induction element 42 and the area of the second planar surface 342 of the susceptor 34, may be greater than an area defined by the maximum extent of the planar induction element 42 (e.g. the area substantially within the outer peripheral loop of a spiral coil). As such the susceptor 34 may be considered oversized in comparison to the planar induction element 42. Having an oversized susceptor 34 may increase the flux experienced the susceptor 34 as a whole, and increase the amount of susceptor available for vaporising liquid.
However, at the same time, portions of the susceptor 34 which are not directly adjacent to the planar induction element 42 will receive a relatively lower amount of flux and therefore generate less heat than portions of the susceptor adjacent to the planar induction element 42, which may increase the time taken for the susceptor as a whole to reach a required vaporisation temperature. In particular, the connecting portion 343 is positioned substantially parallel to the plane, and hence while the connecting portion 343 may heat up when a current is applied through the planar induction element 42, the heating will be substantially less than for the first planar surface 341 and the second planar surface 342. Instead the heating may be primarily by conduction from the portions providing the first planar surface 341 and the second planar surface 342. Aerosol generation is therefore reduced (potentially to zero) in the connecting portion 343 in comparison to the first planar surface 341 and the second planar surface 342. For this reason, the connecting portion 343 may not comprise any of the plurality of perforations 345.
Surrounding the susceptor 34 of Figure 3, is a liquid transport element or wick 35 which is configured to have a shape that can accommodate the susceptor 34. In particular the liquid transport element 35 defines a recess for receiving the susceptor 34, the recess formed by a first portion 351, a second portion 352, and a connecting portion 353. The first portion 351 is configured to provide liquid to the first portion of the susceptor 34 (defining the first planar surface 341), while the second portion 352 is configured to provide liquid to the second portion of the susceptor 34 (defining the second planar surface 342).
The connecting portion 353 allows for liquid flow between the first and second portion 351,352 and / or aid or facilitate the flow of liquid from a reservoir to the first and second portions 351,352. The connecting portion 353 further includes an outlet 354 which aligns with the outlet 344 of the susceptor 34, and which forms part of the air pathway 16 to allow airflow to the outlet 12.
The connecting portion 353 can be formed from a single (e.g. monolithic) element of liquid conducting material along with the first portion 351 and the second portion 352. In some examples, the wick material has a thickness in the range of 0.5 to 2mm and preferably 0.7 to 1.5 mm. For examples, the liquid transport element 35 may comprise a cotton pad (or similar flexible material) which is folded into a shape around the susceptor 34. Alternatively the liquid conduction element 35 may be formed of rigid or inelastic material, such as a stainless steel mesh or a nickel foam, which is formed into a shape comprising the first portion 351, the second portion 352, and the connecting portion 353.
Where the liquid transport element 35 is formed from a magnetically heatable material, such as a steel mesh or a nickel foam, the first portion 351 and the second portion 352 of the liquid transport element 35 can additionally heat up in response to the generation of a magnetic field by the planar induction element 42. In other words, the liquid transport element can be formed from a susceptor material. In comparison to the susceptor 34, the volume and mass of the liquid transport element 35 is significantly greater (for example, the liquid transport element 35 has a width of 0.5 to 2mm, in contrast to a width of 20µm to 70 µm for the susceptor 34). The liquid transport element 35 takes longer to heat up (e.g. requires more energy) in comparison to the susceptor 34 due to the mass of the liquid transport element 35, the greater distance from the induction element 42, and the presence of the susceptor 34 between the liquid transport element 35 and the induction element 42.
In view of the above, the susceptor 34 can provide rapid heating to a vaporisation temperature due to its lower mass and preferential position, whilst a magnetically heatable liquid transport element 35 can absorb energy which would otherwise be lost, and latent heat, which may raise the ambient temperature of the aerosol generating material between vaporisations leading to a decrease in the amount of heating required for the susceptor 34 to reach a vaporisation temperature for a suitable aerosol generating material.
The cartridge 30 of Figure 3 further includes a housing 36 formed of an upper housing 361, a lower housing 362, and a seal 363. The upper housing 361 may instead be called a downstream or mouth-end housing in that it provides the portion of the housing that is towards the mouthpiece outlet 12. In particular, the upper housing 361 is configured to have a mouthpiece shape comprising the outlet 12 for a user to inhale through. The lower housing 362 may instead be called an upstream or device-end housing in that it provides the portion of the housing that is towards the inlet 14 of the system 10, and towards the position of the device or control part 20 when the cartridge 30 is connected to a control part 20.
The upper housing 361 defines an internal volume which is configured to retain a liquid aerosol generating material. In other words, the upper housing 361 provides a reservoir. The lower housing 362 defines a volume (or void) which is configured to receive the susceptor 34 and liquid transport element 35.The lower housing 362 is additionally configured to be inserted into the upper housing to seal the reservoir, to inhibit movement of liquid from the reservoir except via the liquid transport element 35. For examples, the lower housing 362 may comprise the seal 363 (e.g. an o-ring) which is configured to inhibit movement of liquid between a wall of the upper housing 361 and the lower housing 362. The upper and lower housings 361,362 may be formed from, for example, plastic materials using conventional materials and manufacturing methods (e.g. injection moulding). It will be appreciated that Figure 3 is just one example of a cartridge 30, and that in other examples a suitable housing 36 may be provided by different components in different configurations (e.g. reservoir provided in a lower housing 362, or the housing 36 not requiring a seal).
Figure 4 is a exploded perspective drawing of a further example cartridge 30 in accordance with the present disclosure. The cartridge 30 may be for use with an induction assembly 40 comprising the support 44 of Figure 2. The cartridge 30 comprises an upper housing 361, a lower housing 362, a seal 363, a susceptor 34, and a liquid transport element 35. Various aspects of the cartridge 30 may be as described in relation to Figure 1.
In contrast to the example of Figure 3, the example of Figure 4 comprises a susceptor 34 formed from two separate (disconnected) portions each of which provides a planar surface. In other words, the first (susceptor) portion 341 and the second (susceptor) portions 342 of the susceptor 34 are separate from each other (i.e. discontinuous). For example, each portion 341,342 of the susceptor 34 may be provided by a separate planar element formed of suitable material. Similarly to as described in relation Figures 1 and 3, each portion 341,342 of the susceptor 34 comprises a plurality of apertures 345. The recess 38 of the cartridge is defined, at least in part, by the first planar surface provided by the first portion 341 and the second planar surface provided by the second portion 342.
The first (susceptor) portion 341 and the second (susceptor) portions 342 are configured to provide a first planar surface and a second planar surface, respectively, which are of a similar size to the area of the plane of the planar induction element 42 (e.g. the area within the outer spiral of a spiral coil). For example, the area of each of the first planar surface and the second planar surface may be in the range of 100 to 130% of the planar area encompassed by the planar induction element (e.g. the area within the outer spiral of a spiral coil). As such the major portion of the susceptor material is provided parallel and offset from the induction element 42 with only a relatively small amount of susceptor material offset laterally from the from the outer boundaries induction element 42. In other words, if an abstract three dimensional shape were projected from the plane defined by the induction element 42 with the shape having a face corresponding to the shape of the induction element 42 (e.g. a substantially cylinder shape for a spiral coil), the amount of susceptor outside of the volume of the shape would be relatively small in comparison to the susceptor within the volume of the shape. The arrangement of Figure 4 may be advantageous in that the majority of the material of the susceptor portions 341,342 is optimally placed such that the majority of the material is subject to relatively strong inductive heating, with little loss of heat to other parts of the susceptor which are not offset from the induction coil in a direction perpendicular to the induction element. Hence, the time taken for the susceptor 34 to reach a vaporisation temperature of a liquid aerosol generating material contained in the cartridge 30 is reduced.
The liquid transport element 35 additionally comprises a first portion 351 and a second portion 352. The first portion 351 is configured to provide liquid aerosol generating material to the first susceptor portion 341, while the second portion 352 is configured to provide liquid aerosol generating material to the second susceptor portion 342. For example, the first portion 351 and the second portion 352 of the liquid transport element 35 may be positioned between a reservoir for liquid aerosol generating material and a respective one of the first susceptor portion 341 and the second susceptor portion 342. The first portion 351 and the second portion 352 of the liquid transport element 35 may be formed from a flexible material, such as cotton, or a material such as stainless steel or nickel foam as described in relation to Figures 1 and 3.
The first susceptor portion 341 may be shaped to accommodate the first portion 351 of liquid transport element 35 and / or may be shaped to facilitate joining of the first susceptor portion 341 to a feature of the housing 36 (e.g. upper or lower housing 361,362). For example, the first susceptor portion 341 may comprise a substantially flat portion providing the first planar surface, and folded or bent edge portions which engage with the housing 36 and / or first portion 351 of the liquid transport element 35. Similarly, the second susceptor portion 342 may be shaped to accommodate the second portion 352 of liquid transport element 35 and / or may be shaped to facilitate joining of the second susceptor portion 342 to a feature of the housing 36 (e.g. upper or lower housing 361,362).
The housing 36 of Figure 4 is formed from an upper housing 361 and a lower housing 362, similarly to Figure 3. While aspects of the upper housing 361 and the lower housing 362 may be substantially as described in relation to Figure 3, the lower housing 362 of Figure 4 differs from that of Figure 3 in that the lower housing 362 provides an integral features which provide sealing (rather than requiring a separate seal 363), and because the lower housing defines an upper or downstream portion of the recess 38 into which the planar induction coil 42 is inserted when the cartridge 30 is connected to an induction assembly 40 or control unit 20 having an induction assembly 40.
In particular, the lower housing 362 comprises a central airflow channel 364 which forms part of the airflow pathway 16 upstream of the susceptor 34, a first aperture 365 for receiving/accommodating the first susceptor portion 341 and first portion 351 of the liquid transport element 35, and a second aperture 266 for receiving/accommodating the second susceptor portion 342 and second portion 352. It will be appreciated that Figure 4 is just one example of a cartridge 30, and that in other examples a suitable housing 36 may be provided by different components in different configurations (e.g. reservoir provided in a lower housing 362, or the housing 36 not requiring a seal).
Figure 5 is a schematic diagram (not to scale) of an example of a cartridge 30 and induction assembly 40 for use in an aerosol/vapour delivery system 10 in accordance with the present disclosure. Various aspects of the example cartridge and induction assembly of Figure 5 are as described in relation to Figures 1 to 4 and will not be described again in detail.
In comparison to the cartridge 30 of Figure 1, the example cartridge 30 of Figure 5 differs in that the susceptor 34 comprises a single portion on a single side of the planar induction element 42, rather than a first portion on a first side of the planar induction element 42, and a second portion on a second sider of the planar induction element 42 (as per Figures 3 and 4, also). As such the cartridge 30 is configured to provide a single planar surface 341 for vaporisation. For example, the susceptor 34 may be configured similarly to one of the first susceptor portion 341 or the second susceptor portion 342 of Figure 4.
In comparison to the induction assembly 40 of Figure 1, the induction assembly 40 of Figure 5 differs in that the induction assembly further comprises a ferrite shield 48 provided on the side of the planar induction element 42 which is opposite to the susceptor 34 when the induction element 42 is received in the recess 38 of the cartridge 30. The ferrite shield 48 is provided parallel to the plane of the planar induction element 42 and offset from the planar induction element 42. The ferrite shield 48 may be provided by a sheet of suitable material such as a plate or a coating provided within the support 44 or on a surface of the support 44. The ferrite shield 48 acts to block or inhibit flux from the planar induction element 42 from being directed away from the susceptor 34, and may increase the heating of the susceptor 34 by increasing the magnetic flux towards the susceptor 34.
In some examples, such as examples in accordance with Figure 5, the recess 38 is displaced from the centre of the cartridge 30 and instead the recess 38 is positioned towards one side of the cartridge 30. In these examples, the induction assembly 40 has a corresponding configuration in which the induction element 42 is displaced from the centre of the induction assembly 40 so as to align with the recess. This may improve the provision of liquid to the susceptor 34 by increasing the size of the liquid transport element 35 that can be used with the susceptor 34, and / or may allow for the overall size of the cartridge 30 and induction assembly 40 to be reduced.
In some examples, not shown, an induction assembly 40 having a ferrite shield 48 positioned in relation to the plane of the planar induction element 42 as stated above, may be used with a cartridge 30 which comprises first and second planar surfaces (e.g. a cartridge 30 in accordance with Figure 1, 3 or 4). In some of these examples, the planar induction element 42 and recess 38 may be provided substantially centrally to the cartridge 30 and induction assembly 40, as shown in for example Figure 1, 3 or 4. In these examples, the ferrite shield 48 may substantially prevent the inductive heating of the one of the susceptor 34 planar surfaces on the same side of the planar induction element as the ferrite shield 48. In some of these examples, the cartridge 30 may comprise a first reservoir of a first liquid aerosol generating material in fluid communication with a first planar surface, and a second reservoir of a second aerosol generating material in fluid communication with a second planar surface.
In other words, in some examples, the cartridge 30 comprises a first reservoir for a first liquid aerosol generating substrate, the cartridge 30 configured to supply liquid from the first reservoir to the first planar surface 38, wherein the cartridge 30 comprises a second reservoir for a second liquid aerosol generating substrate, the cartridge 30 is configured to supply liquid from the second reservoir to the second planar surface.
In some examples, the cartridge 30 comprises the first liquid aerosol generating substrate and the second liquid aerosol generating substrate, wherein the first liquid aerosol generating substrate is different to the second liquid aerosol generating substrate. For examples, the first liquid aerosol generating substrate and the second liquid aerosol generating substrate may be configured to provide different aerosol such as aerosols with different flavours or different strength concentrations of one or more active substances (e.g. a zero-nicotine aerosol, and an aerosol containing nicotine).
In some of these examples, the ferrite shield 48 may be movable such that a user can move the ferrite shield 48 into the a position adjacent to the induction element 42 in which heating of one of the planar surfaces is inhibited. This may allow a user to change a flavour of the generated vapour by changing whether one or both aerosol generating materials are vaporised. The ferrite shield 48 may be moved electronically based on control signals from the control circuitry 28, or may be moved manually by a user interacting with a manual actuation element configured to move the ferrite shield 48 (e.g. a lever or similar).
In some examples, the ferrite shield 48 is fixed. In these examples, a suitable cartridge 30 may allow for engagement between the cartridge 30 and the induction assembly 40 in two orientations or positions (selectable by a user). In a first orientation or position, the first planar surface of the susceptor 34 is adjacent to the unshielded side of the induction element 42 (the side of the induction element 42 opposite to the side adjacent to the ferrite shield 48) to allow vaporisation of aerosol generating material in the vicinity of the first planar surface. In a second orientation or position the second planar surface of the susceptor 34 is adjacent to the unshielded side of the induction element 42. For example, a user may be able to disconnect the cartridge 30 from the induction assembly 40 and control part 20, rotate the cartridge 30 to a different orientation relative to the induction assembly 40 (e.g. first orientation to second orientation) and reconnect the cartridge 30 to the induction assembly 40 and control part 20; thereby inserting the planar induction element 42 into the recess 38 of the cartridge 30 with a different planar surface of the susceptor 34 adjacent to the side of the planar induction element 42 which is opposite to the side adjacent the ferrite shield 48. In these examples, the user is able to select whether to vaporise the first or second aerosol generating materials by attaching the cartridge 30 to the induction assembly 40 in the first or second orientation.
Figure 6 is a schematic diagram (not to scale) of an example of a cartridge 30 and induction assembly 40 for use in an aerosol/vapour delivery system 10 in accordance with the present disclosure. In addition to the features described in relation to Figures 1 to 5, the cartridge of Figure 6 comprises one or more liquid flow channels 37 and a sub-reservoir 331. The one or more liquid flow channels 37 and sub-reservoir 38, as described herein, may be implemented with any of the cartridge 30 embodiments described in relation to Figures 1, and 3 to 5. The remaining aspects of the example cartridge 30 and induction assembly 40 of Figure 6 are as described in relation to Figures 1 to 5 and will not be described again in detail.
The one or more liquid flow channels 37, which may be called liquid pathways or conduits, are provided adjacent to the liquid transport element 35 (or the susceptor 34 where the susceptor 34 is configured to provide the function of a liquid transport element). The one or more liquid flow channels 37 extend from the reservoir 33 along a surface of the liquid transport element 35 and act to facilitate the ingress of liquid aerosol generating material into the liquid transport element 35. Advantageously this may improve the supply of liquid to the entirety of the liquid transport element 35 by increasing the surface area into which the liquid aerosol generating material can enter the liquid transport element 35. In other words, while in some examples where a liquid flow channel 37 is not present, the liquid can only enter the liquid transport element 35 via the portion of the liquid transport element 35 in contact with the reservoir 33, on examples, where a liquid flow channel 37 (or multiple channels) is present, the liquid can additionally enter the liquid transport element 35 along the surface of the liquid transport element 35 adjacent to the channel 37.
Each liquid flow channel 37 acts to provide a pathway suitable for the conduction of liquid. For example, a liquid flow channel 37 may comprise a cavity or void in which liquid can reside. As an example, liquid may flow into the liquid flow channel 37 from the reservoir 33 to fill the channel 37; the susceptor 34 is heated via inductive heating and liquid in the in the liquid transport element 35 in the vicinity of the susceptor 34 is vaporised; liquid in the liquid flow channel 37 and the reservoir 33 is drawn into the liquid transport element 35 along the entire surface of the liquid transport element 35 in contact with either the reservoir 33 or liquid flow channel 37. The increased surface area allows the liquid transport element 35 to return to a saturated liquid state quicker.
In some examples, one or more of the liquid flow channels 37 are elongated channels (e.g. cavities or voids having a length which is significantly greater that a width). In some examples, the liquid flow channels 37 are elongated channels extending from the reservoir 33 towards the end of the cartridge 30 which is adjacent the control part 20 in use. In some examples, the liquid flow channels 37 are elongated channels extending from the reservoir 33 along the entire length of the liquid transport element 35, or to a furthest extremity of the liquid transport element 35 from the reservoir 33. In some examples, one or more of the liquid flow channels 37 are linear channels (i.e. extending in a straight line). In some examples, one or more of the liquid flow channels 37 include curves and bends (e.g. winding channels).
In some examples, each liquid flow channel 37 is configured to cause a capillary effect on the liquid aerosol generating material to draw liquid into the liquid flow channel 37. For example, a liquid flow channel 37 may have a width in the range of 0.1 mm to 1 mm (the width being perpendicular to an direction of elongation of the channel 37). Without being bound by theory, the capillary effect of a channel 37 on the liquid aerosol generating material may be defined by capillary drive force of the channel 37 which relates to the ability of the liquid flow channel 37 to draw liquid aerosol generating material into by the capillary effect. In some examples, in order to ensure that liquid is drawn into the liquid transport element 35, the liquid transport element 35 is configured to cause a capillary effect having a capillary drive force that is stronger than the capillary drive force of the liquid flow channel 37. For examples, the liquid transport element 35 may be formed of a material having channels or pores of a porous network which are smaller in dimension (e.g. width) than the width of the one or more liquid flow channels 37.
The sub-reservoir 331, sometimes called a secondary reservoir or supplementary reservoir, comprises a cavity or void which is configured to retain an amount of liquid aerosol generating material. In some examples, the sub-reservoir 331 is provided at an opposing end of the liquid transport element 35 (or susceptor 34 where the susceptor 34 is configured to provide the function of the liquid transport element 35) to the reservoir 33. The sub-reservoir 331 is positioned such that after vaporisation of aerosol generating material, the liquid transport element 35 is able to absorb, or receive, liquid from both the reservoir 33 and the sub-reservoir 331. This may improve the distribution of liquid aerosol generating material along the length of liquid transport element 35 (e.g. in contact with the susceptor 34). In particular, this may prevent a portion of the liquid transport element 35 which is distal from the reservoir 33 from being under-saturated (e.g. sub-optimally saturated) during a subsequent activation of the induction element 42, particularly where there is only a relatively short duration between puffs by a user (e.g. activations of the induction element 42).
As such, in some examples, the cartridge 30 comprises a sub-reservoir 331 provided at or towards an opposite end of the susceptor 34 to the reservoir 33, the sub-reservoir 331 configured to hold a smaller volume of liquid aerosol generating substrate than the reservoir 33, and wherein the cartridge 331 is configured to supply liquid from the sub-reservoir 331 to the susceptor 34. For example, the cartridge 30 is configured such that the sub-reservoir 331 can supply liquid to a distal end of the susceptor 34 in comparison to the end of the susceptor closest to the reservoir 33.
The sub-reservoir 331 may be provided by the housing 36 of the cartridge 30 or a different structural component of the cartridge 30. For example, the sub-reservoir 331 can be provided by injection moulding the housing 36 to have a shape defining the sub-reservoir 331. In some examples, the sub-reservoir 331 may be an annular reservoir extending around the air pathway 16, similarly to the reservoir 33. In some examples, there may be more than one sub-reservoir 331 (e.g. two sub-reservoirs on opposing sides of the cartridge 30).
In some examples, the sub-reservoir 331 is configured to hold a volume of liquid in the range of 0.005 ml to 0.1 ml (e.g. the total volume of the sub-reservoir 331). In some examples, the sub-reservoir 331 is configured to hold a volume of liquid in the range of 0.01 ml to 0.05 ml. In some examples, the sub-reservoir 331 is configured to hold a volume of liquid in the range of 0.015 ml to 0.02 ml.
In some examples, the sub-reservoir 331 is configured to hold a volume of liquid corresponding to an amount of liquid aerosol generating material vaporised in a number of puffs (or fractions of a puff). For example, an example system could vaporise approximately 0.09ml of liquid aerosol generating material during an average puff (e.g. over a 3 second period in which the induction element 42 is activated to heat the susceptor 34). As such a sub-reservoir 331 configured to hold a volume of liquid in the range of 0.015 ml to 0.02 ml can hold enough liquid for approximately 2 puffs. In some examples, the sub-reservoir 331 is configured to hold a volume of liquid corresponding to the amount of liquid aerosol generating material vaporised, on average, in 0.5 to 5 puffs. In some examples, the sub-reservoir 331 is configured to hold a volume of liquid corresponding to the amount of liquid aerosol generating material vaporised, on average, in 1 to 3 puffs.
In some examples, the reservoir 33 is configured to hold around 2 ml of liquid (e.g. the total volume of the reservoir 33). For example, the reservoir 33 may be configured to hold a volume of liquid in the range of 1 ml to 4 ml. In some examples, the sub-reservoir 331 is configured to hold a volume of liquid corresponding to a fraction of the total volume of the reservoir 33. In some examples, the sub-reservoir 331 is configured to hold a volume of liquid in the range of 0.2 % to 2.5 % of the total volume of the reservoir 33. In some examples, the sub-reservoir 331 is configured to hold a volume of liquid in the range of 0.5 % to 1.5% of the total volume of the reservoir 33.
In some examples, one or more liquid flow channels 37 fluidly connect the reservoir 33 to the sub-reservoir 331. In these examples, liquid aerosol generating material can flow between the reservoir 33 and the sub-reservoir 331 via the one or more liquid flow channels 37.
In some examples, the sub-reservoir 331 comprises or is formed of a capillary material. For example, the sub-reservoir 331 may comprise a structure having capillary channels or a capillary material may be inserted into the sub-reservoir 331. Similarly to as described in relation to the liquid flow channels 37, a capillary material of the sub-reservoir 331 may exert a lower capillary driving force to a capillary driving force exerted by the liquid transport element 35 to enable liquid to be drawn into liquid transport element 35 from the sub-reservoir 331.
Figure 7 is a diagram of a cross-section through an example cartridge 30 for use in an aerosol/vapour delivery system 10 in accordance with the present disclosure. The cartridge 30 of Figure 7 comprises a susceptor 34 comprising a single flat planar surface 341 (similarly to Figure 5) which is configured to face an induction assembly 40 when the cartridge 30 is engaged with an induction assembly 40 and control unit 20 (i.e. the surface 341 is parallel and offset from a plane of a planar induction element 42 of the induction assembly 40).
The cartridge 30 of Figure 7 further comprises a plurality of liquid flow channels 37 provided in a portion of the housing 36. The plurality of liquid flow channels 37 are provided adjacent to a liquid transport element 35. The plurality of liquid flow channels 37 are configured to direct liquid from a reservoir 33 (not shown) to a surface of the liquid transport element 35 and may be as described in relation to Figure 6.
The surface of the liquid transport element 35 adjacent to the liquid flow channels 37 may be considered a back surface, while the surface of the liquid transport element 35 adjacent to the susceptor 34 may be considered a front surface. Liquid may flow into the back surface of the liquid transport element 35 towards the front surface of the liquid transport element 35 after liquid aerosol generating material is vaporised by the susceptor 34.
The housing 36 comprises a plurality of ribs 39 defining the liquid flow channels 37. For example, each liquid flow channel 37 may be defined by two adjacent ribs of the plurality of ribs 39. Said ribs 39 defining the path of the channel 37. The width of the channel 37 may be the separation distance of the two ribs (e.g. two adjacent ribs 39 may be separated by a distance in the range of 0.1 mm to 1 mm. Similarly, each rib 39 may have a width in the range of 0.1 mm to 1 mm.
While Figure 7 depicts a cartridge 30 having six liquid flow channels 37 and seven ribs 39 (including two end ribs 39 proximal to the susceptor 34), in other examples, there may be fewer than six liquid flow channels 37 (e.g. 4 or less) or greater than six liquid flow channels 37 (e.g. 8 or more, or 12 or more).
Figure 8 is a highly schematic diagram (not to scale) of an example of a mouthpiece, cartridge 30 and induction assembly 40 for use in an aerosol/vapour delivery system 10 in accordance with the present disclosure. The cartridge 30 differs from the cartridges 30 shown in Figures 1, and 3 to 7, in that the cartridge 30 is configured to be received in a separate mouthpiece component 50 (called a mouthpiece 50 herein). The susceptor 34, the liquid transport element 35, the reservoir 33 of the cartridge 30, as well as the induction assembly 40 of Figure 8 are as described in relation to Figure 1 and will not be described again in detail. Alternate embodiments of a cartridge 30, which are suitable for use with a mouthpiece 50 as disclosed in Figure 8, may include aspects described in relation to Figures 3 to 7 (e.g. liquid flow channels 37, a sub-reservoir 331, or a single planar surface).
The cartridge 30 of Figure 8 may be termed a pod or capsule and is configured to be received inside a cavity or void of the mouthpiece 50. For example, the housing 36 of the cartridge 30 is not configured to define a mouthpiece shape, but is instead configured to define a structure which can be received within a component providing mouthpiece 50, and which can accommodate components such as the reservoir 33, a susceptor 34, and a liquid transport element 35.
As depicted in Figure 8, the housing 36 may be a body having a central passage extending between two openings in opposing end faces of the body. The central passage provides a portion of the air pathway 16 of the system 10. The central passageway is further configured (e.g. suitably large) to receive the planar induction element 42. The susceptor 34 provides one or more surfaces of the central passage, each surface parallel and offset from a plane of the planar induction element 42 of the induction assembly 40. The openings in the opposing end faces of the body may be elongated slots (e.g. rectangular or elliptical), and the outer surface of the central passageway may be defined by walls (including walls defined by the susceptor 34) which extend between the periphery of each of the openings. In some examples, not shown, the passageway is not a central passageway (i.e. not disposed centrally in the cartridge 30) and is instead displaced to one side of the cartridge 30 (e.g. for systems where a susceptor 34 is provided on only one side of the induction element 42).
The cartridge 30 includes a liquid transport element 35 which is provided between the susceptor 34 and the reservoir 33. In some examples, the liquid transport element 35 is combined with the susceptor 34 (e.g. by a single material such as a metal foil). The reservoir 33 is provided by cavities defined by the housing 36 and the liquid transport element 35/susceptor 34. For example, the reservoir 33 may be an annular cavity extending between an outer surface of the housing 36 and the components defining the outer surface of the central passageway.
The mouthpiece 50 for use with a separate cartridge 30 comprises a cavity 51 (e.g. void or volume) which is suitable for receiving a cartridge 30. In the example of Figure 8, the cavity 51 is an internal space or volume defined by a housing 52 which also defines the external shape of the mouthpiece 50. For example, the mouthpiece defines an outlet 12 of the air pathway 16 through which a user can inhale. In some examples, the housing 52 is formed from a metal or plastic material (for example, the housing may be formed by plastic injection moulding process).
In some examples, the cavity 51 has a shape and size which corresponds to the outer shape defined by the cartridge 30 but which is larger, (e.g. slightly larger such as 1 % larger) than the outer shape defined by the cartridge 30. This allows the cartridge 30 to be inserted or placed into cavity 51, such that the cartridge 30 is retained in the cavity 51. In some examples, the size of the cartridge 30 and the size of the cavity 51 may be substantially similar such that an interference fit is formed between the housing 52 defining the cavity and the housing 36 defining the cartridge 30.
In some examples, such as those in accordance with Figure 8, the housing 52 comprises two portions. A first, upper, downstream or mouth-end portion 52 and a second, lower, upstream or device-end portion 54. The cavity 51 may be formed by one or both of the upper and lower portions 52,54. In these examples, the mouthpiece 50 may comprise an opening mechanism 56 and a connection mechanism 58.
The opening mechanism 56 is configured to allow for movement of the first portion 52 with respect to the second portion 54, or vice versa. In some examples, the opening mechanism 56 is a hinge or flexible connector. Where the opening mechanism 56 is a hinge, the opening mechanism 56 can allow for rotation of the first portion 54 with respect to the second portion 52. In some examples, the rotation can be with respect to an axis which is perpendicular to the longitudinal axis of the system 1, while in some other examples the rotation with respect to an axis which is parallel to the longitudinal axis of the system 1.
The opening mechanism 56 allows the mouthpiece 50 to be moved between a first configuration in which the cavity 51 is at least partially exposed in order to allow a cartridge 30 to be inserted and / or removed, and a second configuration in which the cavity 51 is substantially closed (except for via openings for the air pathway 16) in order to retain and / or protect a cartridge 30 provided within the cavity 51. The first configuration may be termed an open or accessible configuration because the cavity 51 is open and accessible to a user, and the second configuration may be termed a closed or inaccessible configuration because the cavity 51 is closed and inaccessible to a user.
As such, in some examples, a mouthpiece comprises an opening mechanism configured to allow the mouthpiece to be moved between a first configuration and a second configuration, wherein in the first configuration the cavity is at least partially exposed in order to allow a cartridge to be inserted and / or removed, and wherein the second configuration is configured to retain a cartridge provided within the cavity.
Advantageously, the opening mechanism 56 allows a user to open the cavity 51 without a full disconnection of the first portion 52 from the second portion 54, thereby improving user accessibility because a user does not have to hold each portion 52,54 separately whilst inserting or removing a cartridge 30 from the cavity 51. However, it will be appreciated that in some other examples, an opening mechanism 56 may not be included and instead the first portion 52 and the second portion 54 may fully detach from each other when changing the mouthpiece configuration from the second configuration to the first configuration.
The connection mechanism 58 acts to retain the first portion 52 in contact with the second portion 54 of the housing. For example, the connection mechanism 58 may be a latch or lock which prevents or inhibits the first portion 52 from moving relative to the second portion 54, or vice versa. The connection mechanism 58 is configured to prevent or inhibit the mouthpiece 50 from moving from the closed configuration to the open configuration in order to prevent a cartridge 30 from inadvertently being leaving the cavity 51 prior to a user intending to remove the cartridge 30.
In some examples, the connection mechanism 58 is provided in one or both of the first portion 52 and the second portion 54. For example, the connection mechanism 58 can comprise a corresponding component in each of the first and second portions 52,54 which are configured to engage with each other to prevent or inhibit movement of the first and second portion 52,54 with respect to each other. In some examples, the connection mechanism 58 comprises a mechanical mechanism including a latch or clip in one of the first portion 52 and the second portion 54, and a corresponding component (e.g. a second clip or a ridge) in the other of the first portion 52 and the second portion 54 for retaining the latch or clip. In some examples, the connection mechanism 58 comprises a first magnet in the first portion 52, and a second magnet (attractive to the first magnet) in the second portion 54, the two magnets generating a force that needs to be overcome to move the first portion 52 relative to the second portion 54.
In some examples, the connection mechanism 58 is user actuatable such that a user can interact directly with the connection mechanism 58 to inhibit the connection mechanism 58 from retaining the mouthpiece in the second configuration. In other words, the connection mechanism 58 is user actuatable such that a user can interact directly with the connection mechanism 58 to allow the first portion 52 to move relative to the second portion 54 (e.g. the user may move or bend a latch out of a position with respect to a corresponding clip, or may apply force to overcome the attraction between two magnets).
In some examples, the connection mechanism 58 is electronically controlled (e.g. electrically operated by the control circuitry 28). For example, while not shown, at least a part of the connection mechanism 58 may be electrically connected to the control circuitry 28 and may be operable (e.g. in response to electrical signals) by the control circuitry 28 to activate or deactivate the connection mechanism 58. In some examples, the connection mechanism 58 may comprise an electromagnet and a permanent magnet, where the electromagnet is configured to generate a magnetic field when a current is supplied through the electromagnet, which causes an attractive force to be generated between the permanent magnet and electromagnet. In some examples, the connection mechanism 58 comprises an actuator which is movable in response to an electric signal to engage a latch or similar (such a latch and actuator may be positioned to not be visible to a user when the mouthpiece 50 is in the second configuration).
Advantageously, the connection mechanism 58 can be used to slow down a user, when a user is seeking to change a cartridge 30. For example, when a susceptor 34 is heated by induction the susceptor 34 may heat up to high temperature. Particularly in cases where a user activates the induction element a number of times in a short period (e.g. 10 puffs in 1 minute), elements of the cartridge 30 can become hot (particularly, the susceptor and those components close to the susceptor). If the user were to remove the cartridge 30 immediately after puffing the user (or their clothing or nearby item such as a table) could be burned.
The provision of connection mechanism 58 delays the user from accessing the cartridge 30 immediately, and instead allows heat (thermal energy) to dissipate throughout the cartridge 30 and surrounding elements of the system 10. It will be appreciated that even where the connection mechanism 58 is a simple mechanical mechanism such as a latch, this may still delay the user from accessing the cartridge by a few seconds (e.g. at least 2 to 3 seconds). In some examples, where the connection mechanism 58 is electronically controlled, the control circuitry 28 may implement a timer preventing the connection mechanism 58 from being disengaged for a period of time after a most recent activation of the induction element 42 (e.g. the period of time is in a range of greater than 3 seconds, and preferably greater than 5 seconds). In some examples the period of time may be fixed, whereas in other examples the period of time may be calculated based on the usage of the system up to the last puff (e.g. increased usage prior to the last activation causing the period of time to be greater).
In some examples, not shown, the lower portion 54 may not be a component of the mouthpiece 50. Instead in these examples, the induction assembly 40 or the device 20 define or otherwise provide at least a portion of the cavity 51 for the cartridge 50 (for example, at a minimum the induction assembly 40 or the device 20 may define an end surface of the cavity with the remaining surfaces defined by a single mouthpiece housing component). In these examples, the connection mechanism 58 and / or the opening mechanism 56, as described above, can be provided by the induction assembly 40 or device 20. For example, the mouthpiece 50 may be connected by a hinge (opening mechanism 56) to the induction assembly 40 or to the device 20. As such, in some examples, the mouthpiece 50 comprises at least a component of an connection mechanism, wherein the connection mechanism is configured to retain the mouthpiece in the second configuration.
Furthermore, in some examples, a connection mechanism 58 as described above is provided to connect a cartridge 30 directly to the control unit 20 and/or the induction assembly 40 without the presence of a separate mouthpiece 50. For example, the connection mechanism 58 may engage or lock the cartridge 30 on to the control unit 20 and/or the induction assembly 40 to prevent the cartridge from inadvertently disconnecting.
Figure 9 is a highly schematic diagram (not to scale) of an example of a cartridge 30 and induction assembly 40 for use in an aerosol/vapour delivery system 10 in accordance with the present disclosure. Various aspects of the example cartridge and induction assembly of Figure 9 are as described in relation to Figures 1 to 8 and will not be described again in detail.
The cartridge 30 of Figure 9 differs from that of Figures 1 and 3 to 8 in that the cartridge 30 is configured to provide the air pathway 16 on an opposing side of the susceptor 34 to the side parallel and offset from the induction element 42. In other words, the induction element 42 is not provided directly adjacent to the susceptor 34 with the air pathway 16 being provided between the susceptor 34 and the induction element 42 (or housing 44 of the induction assembly); instead the air pathway 16 is provided between the susceptor 34 and an element of the cartridge 30 such as an inner wall of the housing 36. Alternatively although not shown, the air pathway 16 could be provided between the susceptor 34 and an inner wall of a mouthpiece 50 component, where the cartridge 30 is a cartridge 30 that is configured to be received in a cavity 51 of a mouthpiece 50 as described in relation to Figure 8.
By providing the air pathway 16 on the opposing side of the susceptor 34 to the induction element 42, the resistance to draw of the air pathway 16 can be increased. For example, when the air pathway 16 is provided between the susceptor 34 and induction element 42, the width of the air pathway is limited in order to prevent the susceptor 34 from being spaced too far from the induction element 42 thereby increasing the coupling distance (e.g. the width may be less than 1.5mm, preferably less than 1.2 mm, and more preferably less than 1.1mm). However, by providing the air pathway 16 on the other side of the susceptor 34, the air pathway 16 is constrained primarily by the dimensions of the cartridge 30 (or mouthpiece 50 if appropriate) and hence can be wider (e.g. greater than 2mm and preferably greater than 3mm) thereby allowing a reduced resistance to draw during an inhalation.
In these examples, when the induction assembly 40 is coupled with the cartridge 30 such that the induction element 42 is inserted into a recess of the cartridge 30 with a plane parallel and offset from a planar surface of the susceptor 34, the induction element 42 may be separated from the planar surface of the susceptor 34 by a portion of housing wall 363 configured to prevent leakage from the reservoir and to define the recess (at least in part) for the induction element 42 (and assembly 40). The housing wall 363 may be shaped to define a recess with a shape and size corresponding to the shape and size of the portion of the induction assembly 40 which is inserted into the recess. In some examples, an interference fit may be formed between the housing wall 363 and at least a portion of the induction assembly 40 (e.g. a portion of the housing 44).
In some examples, a liquid transport element 35 is provided between the housing wall 363 and the susceptor 34 to facilitate the provision of liquid from the reservoir 33 to the susceptor 34. While not shown, the cartridge 30 may further include liquid guiding channels 37 (adjacent the housing wall 363) and a sub-reservoir 331 as described in relation to Figure 6 and 7. In some examples, a liquid transport element 35 is not present and instead a void is provided between the susceptor 34 and the housing wall 363 in which liquid is able to flow. In some examples, a capillary structure, such as one or more capillary channels (e.g. liquid guiding channels 37 capable of producing capillary forces), is integrated into the housing wall 363 and is configured to provide liquid across a surface (the surface opposite to the surface adjacent the air pathway 16) of the susceptor 34.
In some examples (for example, where the susceptor comprises a planar sheet of material, such as a 50 micron induction heatable metal sheet)), the coupling distance of the induction element 42 to the susceptor 34 is in the range of less than 2mm and greater than 0.3 mm. In some examples, the coupling distance of the induction element 42 to the susceptor 34 is in the range of less than 1.5 mm and greater than 0.6 mm. In some examples, the coupling distance of the induction element 42 to the susceptor 34 is in the range of less than 1.2 mm and greater than 0.9 mm.
In some examples, the cartridge 30 comprises a liquid transport element 35 formed from an inductively heatable material such as a stainless steel mesh or a nickel foam. Said liquid transport element 35 may also provide the susceptor 34 component (e.g. a single component provides both functions) or may be in addition to the heater 34 (e.g. an inductively heatable sheet material may be provided on one side of the inductively heatable liquid transport element 35 to provide a combined wick-heater atomiser). When the liquid transport element 35 is placed in the flux of the magnetic field, the field penetrates the item and induces electric eddy currents.
In examples in accordance with Figure 9, the use of a inductively heatable liquid transport element 35 may be advantageous in that the inductively heatable liquid transport element 35 can be placed relatively close to the induction element 42. For example, the liquid transport element 35 may be separated from the induction assembly 40 by the housing wall 363 (which may have a width of up to 0.7 mm, and preferably up to 0.5mm), and in some examples a small gap between the induction assembly 40 and the housing wall 363 (which may have a width of less than 0.3mm and preferably less than 0.1 mm to ensure an interference fit). Therefore, in some examples, the coupling distance between the induction element 42 and at least a portion of the inductively heatable liquid transport element 35 is less than 1 mm and preferably less than 0.7mm.
Figure 10 is a flow diagram depicting a method 100 of generating an aerosol from an aerosol generating substrate in an aerosol delivery system 10 in accordance with the present disclosure. The aerosol delivery system 10 comprises a cartridge 30 and a control part 20 (sometimes called device, device part or control unit), wherein the cartridge 30 comprises a susceptor 34, and the control part 20 comprises a planar induction element 42, a power supply 25 and control circuitry 28. The system 10 and its components (e.g. induction assembly 40, cartridge 30 and control part 20) may be as described in relation to any of Figures 1 to 9 and will not be described again in detail.
The method 100 starts with a first step 110 of inserting the planar induction element 42 into the recess 38. The planar induction element 42 is inserted into the recess 38 to position a planar surface of the susceptor 34 to be parallel to a plane defining the planar induction element 38 and offset from the planar induction element 42 in a direction perpendicular to the plane. By a plane defining the planar induction element 38, it is meant the plane in which the planar induction element 38 is substantially arranged (e.g. for a two dimensional spiral coil, the plane of the spiral). By offset from the planar induction element 42 in a direction perpendicular to the plane, it is meant that the planar surface of the susceptor 34 is provided in a direction which is aligned normal to the plane of the planar induction element 42 (e.g. for a two dimensional spiral coil, the susceptor 34 may be displaced from the spiral coil 42 with respect to an axis which passes through the centre point or origin of the spiral coil 42). The planar induction element 42 may be part of an induction assembly 40 and the recess 38 may be part of a cartridge 30, as described in relation to any of Figures 1 to 9.
Alternatively, the first step 110 may be termed as providing the recess 38 adjacent to the planar induction element 42 to position a planar surface of the susceptor 34 to be parallel to a plane defining the planar induction element 38 and offset from the planar induction element 42 in a direction perpendicular to the plane. In other words, it will be appreciated that the relative movement (i.e. insertion) of the induction element 42 into the recess 38 can also be described as the relative movement of the recess 38 with respect to the induction element 42 (e.g. to provide the recess 38 adjacent to, surrounding or overlapping the induction element 42).
In some examples, the method 100 continues with a step 120 of driving the planar induction element 42 to induce current flow in the susceptor 34 to inductively heat the susceptor 34 to inductively heat the susceptor to a first temperature, and so vaporise a portion of the aerosol generating substrate in the vicinity of the susceptor 34. For example, the planar induction element 42 may be driven to heat the susceptor 34 to at least a vaporisation temperature of an aerosol forming component of the aerosol generating substrate (e.g. a liquid from a reservoir 33). The temperature to which the susceptor is driven to vaporise a portion of the aerosol generating substrate in the vicinity of the susceptor 34 can be considered a first temperature or a vaporisation or aerosolisation temperature. In some examples, the first temperature is in the range of between 150°C and 300°C. In some examples, the first temperature is in the range of between 190°C and 220°C.
In some examples, step 120 is triggered by a user input. For example, the user may engage a user input element. For example, the user may interact with a user actuatable element, such as a button, or the user may inhale on the system (e.g. via the outlet 12) to trigger a puff sensor. In addition to the user input element being a user actuatable element such as a button, or a puff sensor, the user input element could also be any sensor capable of identifying a user interaction (e.g. a capacitance sensor, a motion sensor, or an optical sensor). The user input element can be configured to send a signal to the control circuitry 28 indicating that a user input has occurred, and the control circuitry 28 can trigger step 120 (i.e. drive the planar induction element 42). For example, a user inhales on the outlet 12, a puff sensor sends a signal to the control circuitry identifying a user input corresponding to an inhalation (e.g. a signal identifying a pressure drop), and the control circuitry 28 triggers the driving of the planar induction element 42 to induce current flow in the susceptor 34 to inductively heat the susceptor 34 to inductively heat the susceptor to a first temperature.
In some examples, the system 10 comprises a temperature sensor for measuring a temperature of the susceptor 34. The temperature sensor may be configured to measure a value indicative of the temperature of the susceptor 34 rather than directly measuring the susceptor 34 directly. For example, a suitable temperature sensor may be able to determine the temperature of the susceptor 34 based on resistance of an element close to the susceptor 34 (e.g. a thermocouple in the vicinity of the susceptor 34). In some examples, the induction element 42 may be used to measure the temperature of the susceptor 34 based on a strength and frequency of the inductive coupling between the susceptor and the induction element 42. Measurements or signals relating (directly or indirectly) to the temperature of the susceptor 34 can be sent to the control circuitry 28, and used to control how the induction element 42 is driven (i.e. to achieve or maintain a temperature).
In some examples, the method ends after driving the induction element 42 to induce current flow in the susceptor to inductively heat the susceptor to a first temperature. For example, the control circuitry 120 can cease to drive the induction element 42 to induce current flow in the susceptor 34 to inductively heat the susceptor 34 to a first temperature after a period of time corresponding to a user's puff, and / or corresponding to a predicted amount of aerosol generation (e.g. based on knowledge of the energy input to the system and energy required to vaporise the aerosol generating substrate, and either actively calculated during use or based on predetermined data, such as a look-up table, for a particular system 10 configuration).
In some examples, the method ends after driving the induction element 42 to induce current flow in the susceptor to inductively heat the susceptor to a first temperature for a fixed period of time. In some examples, the fixed period of time may be a period of time in the range of 1.5 to 5 seconds. In some examples, the fixed period of time may be a period of time in the range of 2.5 to 4 seconds.
In some examples, the method ends after driving the induction element 42 to induce current flow in the susceptor to inductively heat the susceptor to a first temperature when a user input (e.g. inhalation, button press, or similar as described above) ceases to be provided. For example, a user ceases to inhale of the system 10, the puff sensor sends a signal indicating that air pressure has increased, and the control circuitry 28 stops driving the induction element 42. Alternatively, a user ceases to press a button of the system 10, the button sends a signal indicating that the button is not being pressed, and the control circuitry 28 stops driving the induction element 42. In some examples, the control circuitry 28 implements a maximum activation period even where the user continues to trigger a user input mechanism. This may prevent overheating of the system 10, if for example the user input element has malfunctioned. In some examples, the maximum activation period is a period in the range of 6 to 15 seconds. In some examples, the maximum activation period is a period in the range of 7 to 12 seconds. The method 100 may, in some examples, end after step 120.
In some examples, the method 100 comprises a further step 115 of driving the planar induction element 42 to induce current flow in the susceptor 34 to inductively heat the susceptor 34 to a second temperature that is a lower temperature than the first temperature, and which is not sufficient to vaporise a portion of the aerosol generating substrate in the vicinity of the susceptor 34. In other words, the second temperature is lower than a temperature required to vaporise the portion of the aerosol generating substrate in the vicinity of the susceptor. The second temperature may be considered a preheat temperature. In some examples, the second temperature is in the range of 80°C to 200°C. In some examples, the second temperature is in the range of 120°C to 170°C.
As such, in some examples, in accordance with step 115 the method 100 comprises driving the planar induction element to induce current flow in the susceptor to inductively heat the susceptor to a first temperature so as to vaporise the portion of the aerosol generating substrate in the vicinity of the susceptor, and wherein the method further comprises driving the planar induction element to induce current flow in a susceptor to inductively heat the susceptor to a second temperature which is lower than the first temperature and lower than a temperature required to vaporise the portion of the aerosol generating substrate in the vicinity of the susceptor.
It will be appreciated that the control circuitry 28 is able to drive the planar induction element 42 to induce current flow in the susceptor 34 to inductively heat the susceptor 34 to a particular temperature by modifying the power supplied through the planar induction element. For example, the control circuitry 28 can monitor the temperature of the susceptor by a suitable sensor (e.g. thermocouple or based on a shift in resonant frequency detectable by the planar induction element 42), and can turn alter the power supplied through the planar induction element. As an example, the control circuitry 28 can supply power in a periodic pulses at a set frequency (e.g. 500-50Hz) until a required temperature is reached. As long as the susceptor 34 is at or above the required temperature the control circuitry 28 can prevent the supply of power during the next scheduled pulse. When the susceptor falls below the required temperature, the control circuitry 28 can resume supplying pulses to drive the planar induction element 42.
The provision of a preheat temperature may be particular advantageous for use with a susceptor 34 formed from a high mass element such as a block element formed from steel mesh or nickel foam, and / or when a planar susceptor 34 such as a sheet is used with a wick 35 formed from an inductively heatable material (such as steel mesh or nickel foam). Such a susceptor 34 and / or wick 35 may take a relatively long time to heat due to the high mass, but is able to store latent heat between activations. Hence, by maintaining the susceptor 34 and / or wick at a higher than ambient temperature, the time taken to heat the susceptor 34 to a first temperature so at to vaporise a portion of the aerosol generating substrate in the vicinity of the susceptor 34 is reduced. Furthermore, the high mass of the susceptor 34 and / or wick 35 increases the time taken for the temperature of the susceptor 34 to return to ambient conditions because the susceptor 34 and / or wick 35 has an increased bulk heat capacity which is less easily dissipated into the surrounding system 10 because of the reduced ratio of external surface area to volume ratio in comparison to a planar element such as a thin sheet of metal.
In some examples, the planar induction element 42 is driven to induce current flow in the susceptor 34 to inductively heat the susceptor 34 to the second temperature in response to a stimulus. In some examples, the control circuitry is configured to drive the planar induction element to induce current flow in a susceptor to inductively heat the susceptor to a second temperature in response to a stimulus, wherein the stimulus comprises one or more of a signal indicative of the connection of a cartridge to the induction assembly and / or control unit, and a signal indicative of a user's intention to begin a session of usage.
In some examples, a stimulus may be the detection of the connection of a cartridge 30 to the induction assembly 40 and / or device 20. In some examples, the control circuitry 28 may be able to determine that a cartridge 30 has already been attached (i.e. is currently attached) based on a measurement or sensor reading (e.g. from a sensor for detecting attachment of a cartridge 30 such as an optical sensor or resistive sensor, or based on a signal from the induction element 42 indicating that a inductively heatable element has been moved towards the induction element). In some examples, a stimulus may be the user pressing a button of the device 20, or the user taking a first puff on the device 20 (triggering a puff sensor, if present).
A stimulus may be indicative of a user's intention to begin a session of usage (e.g. a user's intention to take a series of puffs on the system 10 (by puff it is meant a user will inhale on the outlet 12 of the system 10). In some examples, the method 100 comprises (the control circuitry 28) driving the planar induction element to induce current flow in the susceptor to inductively heat the susceptor to a second temperature in response to a stimulus, wherein the stimulus comprises one or more of a signal indicative of the connection of a cartridge to the induction assembly and / or control unit, and a signal indicative of a user's intention to begin a session of usage.
In some examples, the control circuitry 28 is configured to maintain the susceptor 34 at the second temperature prior to raising the temperature to the first temperature during an activation of the device 20 by a user (e.g. a puff), and / or the control circuitry 28 is configured to maintain the susceptor 34 at the second temperature between activations of the device 20 by a user. In other words, the control circuitry is configured to maintain the susceptor at the second temperature prior to raising the temperature to the first temperature in response to a signal indicating that a user is interacting with a user input element, and / or the control circuitry is configured to maintain the susceptor at the second temperature between signals indicating that a user is interacting with a user input element. By maintaining the temperature of the susceptor 34 at the second temperature, the time taken to ramp the temperature up to the first temperature can be decreased, thereby leading to the quicker production of a vapor (if an aerosol generating substrate is present). As discussed above, a user input element may comprise one or more of a button, a capacitance sensor, a motion sensor, an optical sensor and a pressure sensor, or any other suitable input mechanism.
As such, in some examples, the method 100 comprises driving the planar induction element 42 to induce current flow in the susceptor 34 to inductively heat the susceptor 34 from the second temperature to the first temperature in response to a signal indicating that a user is interacting with a user input element. For example, while the control circuitry 28 is driving the planar induction element 42 to induce current flow in the susceptor 34 to inductively heat the susceptor 34 to the second temperature, a user may press a button or inhale on the system 10, and the control circuitry 28 may switch to driving the planar induction element to induce current flow in the susceptor 34 to inductively heat the susceptor from the second temperature.
In some examples, the control circuitry 28 is configured to perform step 115 (i.e. driving the planar induction element 42 to induce current flow in the susceptor 34 to inductively heat the susceptor 34 to a second temperature that is a lower temperature than the first temperature), after performing step 120 (driving the planar induction element 42 to induce current flow in the susceptor 34 to inductively heat the susceptor 34 to inductively heat the susceptor to a first temperature). In some examples, this is in addition to driving the planar induction element 42 to induce current flow in the susceptor 34 to inductively heat the susceptor 34 to a second temperature that is a lower temperature than the first temperature prior to a first puff (e.g. in response to a stimulus such as insertion of the planar induction element 42 into the recess 38).
In some examples, the control circuitry 28 is further configured to alternate between driving the planar induction element 42 to heat the susceptor 34 to the first temperature and the driving the planar induction element 42 to heat the susceptor 34 to the second temperature, in response to receiving a user input and not receiving a user input, respectively. For example, when the user inhales, or indicates they are inhaling (e.g. button press), the susceptor 34 is heated to the first temperature, and when the user ceases to inhale, or ceases to indicate they are inhaling (e.g. stops pressing a button), the susceptor 34 is heated to the second temperature (it will be appreciated that this may involve ceasing to drive the planar induction element 42 until the susceptor 34 cools from the first temperature to the second temperature, and then periodically driving the planar induction element 42 to maintain the susceptor 34 at the second temperature).
As such, in some examples the method comprises maintaining the susceptor at the second temperature after a signal indicating that a user is interacting with the user input element has stopped, and / or between signals indicating that a user is interacting with the user input element.
In some examples, where the method comprises step 115, the method 100 additionally comprises a step 125 of ceasing to drive the induction element 42 after a period of inactivity. The control circuitry 28 may be configured to maintain the susceptor at the second temperature for a period of time in response to a stimulus, and to cease driving the planar induction element 42 if an input from the user is not received before the end of the period of time. In other words, in some examples, the control circuitry is configured to cease driving the planar induction element to induce current flow in the susceptor to maintain the susceptor at the second temperature after a period of inactivity. As above, the input (i.e. action indicating activity) may be a button press or a puff (measured by a puff sensor) indicating that the user is inhaling, or intends to inhale) on the system 10. In some examples, the period of inactivity is in the range of 10 seconds to 120 seconds. In some examples, the period of inactivity is in the range of between 20 seconds to 60 seconds. The method 100 may, in some examples, end after step 125.
When the method 100 ends, the system 10 may enter a standby mode or a low power sleep mode. For example, after step 120 or after step 125, the control circuitry 28 may enter a standby mode where the control circuitry 28 periodically interrogates any user input elements for indications that the user is inhaling or intending to inhale on the device (or for other interactions relation to control of the system such as checking battery levels, changing heater temperature and turning off or resetting the device). In some examples, if no user inputs are received for a period of time (e.g. 5 to 10 minutes), the control circuitry 28 may turn the system 10 off or place the system 10 in a low power sleep mode.
In some examples, there is a connection mechanism 58 (e.g. as described in relation to figure 8) configured to retain a cartridge 30 as part of the aerosol delivery system 10. The method can additionally comprise engaging and disengaging the connection mechanism 58, wherein the connection mechanism 58 is electronically operable (e.g. by the control circuitry 28). In some examples, the connection mechanism 58 connects different portions of a mouthpiece 50 which define a cavity 51, the connection mechanism 58 connects a mouthpiece 50 to the control unit 20 and/or the induction assembly 40 (a cavity 51 for the cartridge 30 being provided by one or more of the mouthpiece 50, control unit 20 and induction assembly 40), or the connection mechanism 58 connects the cartridge directly to the control unit 20 and/or the induction assembly 40 (e.g. there is no separate mouthpiece 50).
In some examples, the method 100 further comprises (not shown) engaging a connection mechanism 58 configured to retain a cartridge as part of an aerosol delivery system, and disengaging the connection mechanism. By disengaging the connection mechanism, a user is able to remove and / or attach a cartridge 30 (e.g. by inserting a cartridge 30 into a cavity 51). By implementing such a connection mechanism 58 a risk to a user of injury or a risk of damage to the surroundings can be reduced, because disabling or disengaging the connection mechanism can delay the user from removing the cartridge for a few seconds; in which time the susceptor 34 can cool to a lower temperature.
In some examples, the method comprises engages the connection mechanism 58 in response to the control circuitry 28 determining that a cartridge has been attached to the system. In some examples, the method comprises engages the connection mechanism 58 in response to the control circuitry 28 receiving an input from a user indicating the connection mechanism 58 should be engaged. For example the connection mechanism 58 may be engaged in response to a first activation of the aerosol delivery system 10.
In some examples, the method comprises disengaging the connection mechanism 58 in response to the control circuitry 28 receiving an input from a user indicating the connection mechanism 58 should be disengaged (e.g. a button press or combination of button presses). In some examples, the method comprises disengaging the connection mechanism 58 in response to the control circuitry 28 entering a standby mode or a low power sleep mode. In some examples, the method comprises disengaging the connection mechanism 58 in response to the control circuitry 28 ceasing to drive the induction element 42 after a period of inactivity. In some examples, the method comprises disengaging the connection mechanism 58 in response to the control circuitry 28 determining that an amount of time has passed since a last activation (e.g. the time since the control circuitry 28 caused the susceptor to be heated to the first temperature). In some of these examples, the amount of time since a last activation may be in the range of 2 to 10 seconds or 3 to 5 seconds. In some examples, the method comprises disengaging the connection mechanism 58 in response to the control circuitry 28 determining that the susceptor 34 is below a threshold temperature.
Thus, there has been described a cartridge for use in an aerosol delivery system for generating an aerosol from an aerosol-generating substrate, the cartridge for use with an induction assembly, the cartridge comprising a recess configured to receive a planar induction element, and a susceptor comprising a planar surface positioned to be parallel to a plane defining the planar induction element and offset from the planar induction element in a direction perpendicular to the plane when the planar induction element is received in the recess.
Thus, there has also been described an induction assembly for use with a cartridge, the induction assembly comprising a planar induction element, the planar induction element operable to induce current flow in a susceptor of the cartridge to inductively heat the susceptor, wherein the induction assembly is configured to be received at least partially by a recess of the cartridge such that a plane defining the planar induction element is parallel to and offset from a planar surface of the susceptor in a direction perpendicular to the plane.
Thus, there has further been described a control unit for use in an aerosol delivery system for generating an aerosol from an aerosol-generating substrate, the control unit comprising: an induction assembly, a power supply for supplying power to the planar induction element, and control circuitry for controlling the supply of power to the planar induction element, wherein the control circuitry is configured to drive the planar induction element to induce current flow in a susceptor to inductively heat the susceptor and so vaporise a portion of the aerosol generating substrate in the vicinity of the susceptor.
Thus, there has still further been described a method of generating an aerosol from an aerosol generating substrate in an aerosol delivery system, the aerosol delivery system comprising a cartridge and a control unit, wherein the cartridge comprises a susceptor and a recess, and the control unit comprises a planar induction element, a power supply and control circuitry, the method comprising: inserting the planar induction element into the recess to position a planar surface of the susceptor to be parallel to a plane defining the planar induction element and offset from the planar induction element in a direction perpendicular to the plane, and driving the planar induction element to induce current flow in the susceptor to inductively heat the susceptor and so vaporise a portion of the aerosol generating substrate in the vicinity of the susceptor.
As noted, a heater in accordance with the disclosure is a susceptor for induction heating of a liquid aerosol generating material, as described with regard to cartridges shown in Figures 2 to 9. In some other examples, a heater in accordance with the disclosure may be used for induction heating of an alternate aerosol generating material such as a gel aerosol generating material (e.g. a thermo-reversible gel).
In conclusion, in order to address various issues and advance the art, this disclosure shows by way of illustration various embodiments in which the claimed invention(s) may be practiced. The advantages and features of the disclosure are of a representative sample of embodiments only, and are not exhaustive and/or exclusive. They are presented only to assist in understanding and to teach the claimed invention(s). It is to be understood that advantages, embodiments, examples, functions, features, structures, and/or other aspects of the disclosure are not to be considered limitations on the disclosure as defined by the claims or limitations on equivalents to the claims, and that other embodiments may be utilised and modifications may be made without departing from the scope of the claims. Various embodiments may suitably comprise, consist of, or consist essentially of, various combinations of the disclosed elements, components, features, parts, steps, means, etc. other than those specifically described herein, and it will thus be appreciated that features of the dependent claims may be combined with features of the independent claims in combinations other than those explicitly set out in the claims. The disclosure may include other inventions not presently claimed, but which may be claimed in future.
Furthermore, there is a great degree of flexibility in the design/configuration of the aerosol provision system as a whole, as is exemplified at least by the various possibilities of features as outlined in the set of clauses following this paragraph. For the avoidance of any doubt, it will be commensurately appreciated that any features from these clauses may be combined as required in any combination beyond those as expressly set out in these clauses, noting the great flexibility and interchangeability in the usage of such features which the present disclosure clearly provides for.

Clauses

Clause 1. A cartridge for use in an aerosol delivery system for generating an aerosol from an aerosol-generating substrate, the cartridge for use with an induction assembly, the cartridge comprising:

a recess configured to receive a planar induction element; and
a susceptor comprising a planar surface positioned to be parallel to a plane defining the planar induction element and offset from the planar induction element in a direction perpendicular to the plane when the planar induction element is received in the recess.

Clause 2. The cartridge of clause 1, wherein the recess is defined at least in part by the planar surface of the susceptor, the planar surface of the susceptor positioned to be adjacent to the planar induction element when the planar induction element is received in the recess.
Clause 3. The cartridge of any preceding clause, wherein the recess forms a portion of an air path extending through the cartridge.
Clause 4. The cartridge of any preceding clause, wherein the planar surface is offset from the planar induction element by an offset distance in a range of less than 2 mm.
Clause 5. The cartridge of clause 4, wherein the planar surface is offset from the planar induction element by an offset distance in a range of less than 1.5 mm.
Clause 6. The cartridge of any preceding clause, wherein the susceptor comprises a plurality of apertures extending through the susceptor.
Clause 7. The cartridge of clause 6, wherein the plurality of apertures are arranged in a pattern, the number density of the plurality of apertures varying from a peripheral edge bordering the planar surface of the susceptor towards a centre of the planar surface of the susceptor.
Clause 8. The cartridge of clause 7, wherein the density of the plurality of apertures increases from the peripheral edge towards the centre.
Clause 9. The cartridge of any preceding clause, wherein the cartridge comprises a reservoir for a liquid aerosol generating substrate, wherein the cartridge is configured to supply liquid from the reservoir to the susceptor.
Clause 10. The cartridge of clause 9, wherein the cartridge comprises a liquid transport element configured to wick a liquid aerosol generating substrate towards the susceptor.
Clause 11. The cartridge of clause 10, wherein the liquid transport element is formed of a susceptor material.
Clause 12. The cartridge of any of clauses 9 to 11, wherein the cartridge comprises one or more liquid flow channel for guiding liquid aerosol generating substrate from the reservoir.
Clause 13. The cartridge of clause 12, wherein the one or more liquid flow channels comprise a capillary channel.
Clause 14. The cartridge of any of clauses 9 to 13, wherein the cartridge comprises a sub-reservoir provided at or towards an opposite end of the susceptor to the reservoir, the sub-reservoir configured to hold a smaller volume of liquid aerosol generating substrate than the reservoir, and wherein the cartridge is configured to supply liquid from the sub-reservoir to the susceptor.
Clause 15. The cartridge of clause 14, wherein the sub-reservoir is configured to hold a volume of liquid in the range of 0.2 % to 2.5 % of a volume of the reservoir.
Clause 16. The cartridge of any of clauses 14 to 15, wherein the sub-reservoir is configured to hold a volume of liquid in the range of 0.5 % to 1.5% of the volume of the reservoir.
Clause 17. The cartridge of any of clauses 14 to 16, wherein the sub-reservoir is configured to hold a volume of liquid in the range of 0.005 ml to 0.1 ml.
Clause 18. The cartridge of any preceding clause, wherein the planar surface is a first planar surface, wherein the susceptor comprises a second planar surface positioned to be parallel to the plane of the planar induction element and offset from the planar induction element in a direction perpendicular to the plane, when the planar induction element is received in the recess, the second planar surface being provided on an opposite side of the recess to the first planar surface.
Clause 19. The cartridge of clause 18, wherein the recess is defined at least in part by the second planar surface of the susceptor, the second planar surface of the susceptor positioned to be adjacent to the planar induction element when the planar induction element is received in the recess.
Clause 20. The cartridge of clause 18 or 19, wherein the susceptor comprises a sheet providing the first planar surface, the second planar surface, and a connecting portion joining the first planar surface to the second planar surface.
Clause 21. The cartridge of clause 20, wherein the recess is defined at least in part by the connecting portion.
Clause 22. The cartridge of clause 20 or 21, wherein a thickness of the sheet is in the range of one or more of 20 µm to 70 µm, 30 µm to 60 µm, and 40 µm to 55 µm.
Clause 23. The cartridge of clause 18 or 19, wherein the susceptor comprises a first sheet providing the first planar surface and a second sheet providing the second planar surface, the first sheet separate from the second sheet.
Clause 24. The cartridge of clause 23, wherein a first thickness of the first sheet is in the range of one or more of 20 µm to 70 µm, 30 µm to 60 µm, and 40 µm to 55 µm, and / or a second thickness of the second sheet is in the range of one or more of 20 µm to 70 µm, 30 µm to 60 µm, and 40 µm to 55 µm.
Clause 25. The cartridge of any of clauses 18 to 24, wherein the cartridge comprises a first reservoir for a first liquid aerosol generating substrate, the cartridge configured to supply liquid from the first reservoir to the first planar surface, wherein the cartridge comprises a second reservoir for a second liquid aerosol generating substrate, the cartridge is configured to supply liquid from the second reservoir to the second planar surface.
Clause 26. The cartridge of clause 25, wherein the cartridge comprises the first liquid aerosol generating substrate and the second liquid aerosol generating substrate, wherein the first liquid aerosol generating substrate is different to the second liquid aerosol generating substrate.
Clause 27. The cartridge of any preceding clause, wherein the susceptor is formed of a material having a capillary structure configured to wick a liquid aerosol generating substrate.
Clause 28. The cartridge of clause 27, wherein the susceptor is formed of one of a wire wool, mesh or metal foam.
Clause 29. The cartridge of clause 28, wherein the susceptor comprises a nickel foam or a cupro-nickel foam.
Clause 30. The cartridge of clause 28, wherein the susceptor comprises a stainless steel mesh.
Clause 31. The cartridge of any preceding clause, wherein the cartridge is configured to provide a mouthpiece for a user to inhale an aerosol generated from an aerosol-generating substrate.
Clause 32. A mouthpiece for use in an aerosol delivery system, wherein the mouthpiece comprises an outlet and a cavity configured to accommodate at least a portion of the cartridge in accordance with any of clauses 1 to 30.
Clause 33. The mouthpiece of clause 32, wherein the mouthpiece comprises an opening mechanism configured to allow the mouthpiece to be moved between a first configuration and a second configuration, wherein in the first configuration the cavity is at least partially exposed in order to allow a cartridge to be inserted and / or removed, and wherein the second configuration is configured to retain a cartridge provided within the cavity.
Clause 34. The mouthpiece of clause 33, wherein the mouthpiece comprises at least a component of an connection mechanism, wherein the connection mechanism is configured to retain the mouthpiece in the second configuration.
Clause 35. The mouthpiece of clause 34, wherein the connection mechanism is user actuatable such that a user can interact directly with the connection mechanism to inhibit the connection mechanism from retaining the mouthpiece in the second configuration.
Clause 36. An induction assembly for use with a cartridge in accordance with any of clauses 1 to 31, the induction assembly comprising a planar induction element, the planar induction element operable to induce current flow in a susceptor of the cartridge to inductively heat the susceptor, wherein the induction assembly is configured to be received at least partially by a recess of the cartridge such that a plane defining the planar induction element is parallel to and offset from a planar surface of the susceptor in a direction perpendicular to the plane.
Clause 37. The induction assembly of clause 36, wherein the planar induction element is a flat spiral coil.
Clause 38. The induction assembly of clause 37, wherein the flat spiral coil is formed from a resistive wire.
Clause 39. The induction assembly of clause 36, wherein the planar induction element comprises one or more conductive layers deposited upon a support.
Clause 40. The induction assembly of clause 39, wherein the one or more conductive layers comprise a metal or a metal alloy.
Clause 41. The induction assembly of clause 39 or 40, wherein the one or more conductive layers comprise copper, nickel, silver, gold, chromium, palladium, tin, aluminium, platinum, tungsten or zinc.
Clause 42. The induction assembly of any preceding clause, wherein the induction assembly comprises a ferrite shield, wherein at least a portion of the ferrite shield is provided parallel and adjacent to the plane of the planar induction element, wherein the ferrite shield is positioned on an opposite side of the planar induction element to the planar surface of the susceptor when the planar induction element is received in the recess of the cartridge.
Clause 43. A control unit for use in an aerosol delivery system for generating an aerosol from an aerosol-generating substrate, the control unit comprising:

the induction assembly of any of clauses 36 to 42;
a power supply for supplying power to the planar induction element; and
control circuitry for controlling the supply of power to the planar induction element, wherein the control circuitry is configured to drive the planar induction element to induce current flow in a susceptor to inductively heat the susceptor and so vaporise a portion of the aerosol generating substrate in the vicinity of the susceptor.

Clause 44. The control unit of clause 43, wherein the induction assembly is releasably attached to the control unit.
Clause 45. The control unit of clause 43 or clause 44, wherein the control circuitry is configured to drive the planar induction element to induce current flow in the susceptor to inductively heat the susceptor to a first temperature so as to vaporise the portion of the aerosol generating substrate in the vicinity of the susceptor, and wherein the control circuitry is configured to drive the planar induction element to induce current flow in a susceptor to inductively heat the susceptor to a second temperature which is lower than the first temperature and lower than a temperature required to vaporise the portion of the aerosol generating substrate in the vicinity of the susceptor.
Clause 46. The control unit of clause 45, wherein the second temperature is a temperature in the range of 80°C to 200°C.
Clause 47. The control unit of clause 45 or clause 46, wherein the control circuitry is configured to drive the planar induction element to induce current flow in the susceptor to inductively heat the susceptor to a second temperature in response to a stimulus, wherein the stimulus comprises one or more of a signal indicative of the connection of a cartridge to the induction assembly and / or control unit, and a signal indicative of a user's intention to begin a session of usage.
Clause 48. The control unit of any of clauses 45 to 47, wherein the control circuitry is configured to drive the planar induction element to induce current flow in the susceptor to inductively heat the susceptor from the second temperature to the first temperature in response to a signal indicating that a user is interacting with a user input element.
Clause 49. The control unit of clause 48, wherein the control circuitry is configured to maintain the susceptor at the second temperature after a signal indicating that a user is interacting with the user input element has stopped, and / or between signals indicating that a user is interacting with the user input element.
Clause 50. The control unit of clause 48 or clause 49, wherein the control unit comprises the user input element, the user input element comprising one or more of a button, a capacitance sensor, a motion sensor, an optical sensor and a pressure sensor.
Clause 51. The control unit of any of clauses 45 to 50, wherein the control circuitry is configured to cease driving the planar induction element to induce current flow in the susceptor to maintain the susceptor at the second temperature after a period of inactivity.
Clause 52. The control unit of clause 51, wherein the period of inactivity is in the range of 10 seconds to 120 seconds.
Clause 53. An aerosol delivery system for generating an aerosol from an aerosol generating substrate, the aerosol delivery system comprising:

the cartridge of clause 31, or the cartridge of any of clauses 1 to 30 and, optionally, the mouthpiece of any of clauses 32 to 35; and
the control unit of any of clauses 43 to 52.

Clause 54. A method of generating an aerosol from an aerosol generating substrate in an aerosol delivery system, the aerosol delivery system comprising a cartridge and a control unit, wherein the cartridge comprises a susceptor and a recess, and the control unit comprises a planar induction element, a power supply and control circuitry, the method comprising:

inserting the planar induction element into the recess to position a planar surface of the susceptor to be parallel to a plane defining the planar induction element and offset from the planar induction element in a direction perpendicular to the plane;
driving the planar induction element to induce current flow in the susceptor to inductively heat the susceptor and so vaporise a portion of the aerosol generating substrate in the vicinity of the susceptor.

Clause 55. The method of clause 54, wherein the method comprises driving the planar induction element to induce current flow in the susceptor to inductively heat the susceptor to a first temperature so as to vaporise the portion of the aerosol generating substrate in the vicinity of the susceptor, and wherein the method further comprises driving the planar induction element to induce current flow in a susceptor to inductively heat the susceptor to a second temperature which is lower than the first temperature and lower than a temperature required to vaporise the portion of the aerosol generating substrate in the vicinity of the susceptor.
Clause 56. The method of clause 55, wherein the second temperature is a temperature in the range of 80°C to 200°C.
Clause 57. The method of clause 55 or clause 56, wherein the method comprises driving the planar induction element to induce current flow in the susceptor to inductively heat the susceptor to a second temperature in response to a stimulus, wherein the stimulus comprises one or more of a signal indicative of the connection of a cartridge to the induction assembly and / or control unit, and a signal indicative of a user's intention to begin a session of usage.
Clause 58. The method of any of clauses 55 to 57, wherein the method comprises driving the planar induction element to induce current flow in the susceptor to inductively heat the susceptor from the second temperature to the first temperature in response to a signal indicating that a user is interacting with a user input element.
Clause 59. The method of clause 58, wherein the method comprises maintaining the susceptor at the second temperature after a signal indicating that a user is interacting with the user input element has stopped, and / or between signals indicating that a user is interacting with the user input element.
Clause 60. The method of any of clauses 54 to 59, wherein the method comprises ceasing to drive the planar induction element to induce current flow in the susceptor to maintain the susceptor at the second temperature after a period of inactivity.
Clause 61. The method of clause 60, wherein the period of inactivity is in the range of 10 seconds to 120 seconds.
Clause 62. The method of any of clauses 54 to 61, wherein the method comprises engaging a connection mechanism configured to retain a cartridge as part of an aerosol delivery system, and disengaging the connection mechanism, wherein the connection mechanism is electronically operable.

Claims

A cartridge for use in an aerosol delivery system for generating an aerosol from an aerosol-generating substrate, the cartridge for use with an induction assembly, the cartridge comprising:
a recess configured to receive a planar induction element; and

a susceptor comprising a planar surface positioned to be parallel to a plane defining the planar induction element and offset from the planar induction element in a direction perpendicular to the plane when the planar induction element is received in the recess.
The cartridge of claim 1, wherein the recess is defined at least in part by the planar surface of the susceptor, the planar surface of the susceptor positioned to be adjacent to the planar induction element when the planar induction element is received in the recess.
The cartridge of any preceding claim, wherein the recess forms a portion of an air path extending through the cartridge.
The cartridge of any preceding claim, wherein the planar surface is offset from the planar induction element by an offset distance in a range of less than 2 mm; and optionally wherein the planar surface is offset from the planar induction element by an offset distance in a range of less than 1.5 mm.
The cartridge of any preceding claim, wherein the susceptor comprises a plurality of apertures extending through the susceptor; and optionally wherein the plurality of apertures are arranged in a pattern, the number density of the plurality of apertures varying from a peripheral edge bordering the planar surface of the susceptor towards a centre of the planar surface of the susceptor.
The cartridge of any preceding claim, wherein the cartridge comprises a reservoir for a liquid aerosol generating substrate, wherein the cartridge is configured to supply liquid from the reservoir to the susceptor; and optionally wherein the cartridge comprises one or more liquid flow channel for guiding liquid aerosol generating substrate from the reservoir.
The cartridge of claim 6, wherein the cartridge comprises a sub-reservoir provided at or towards an opposite end of the susceptor to the reservoir, the sub-reservoir configured to hold a smaller volume of liquid aerosol generating substrate than the reservoir, and wherein the cartridge is configured to supply liquid from the sub-reservoir to the susceptor; and optionally, wherein the sub-reservoir is configured to hold a volume of liquid in the range of 0.2 % to 2.5 % of a volume of the reservoir.
The cartridge of any preceding claim, wherein the planar surface is a first planar surface, wherein the susceptor comprises a second planar surface positioned to be parallel to the plane of the planar induction element and offset from the planar induction element in a direction perpendicular to the plane, when the planar induction element is received in the recess, the second planar surface being provided on an opposite side of the recess to the first planar surface; and optionally, wherein the recess is defined at least in part by the second planar surface of the susceptor, the second planar surface of the susceptor positioned to be adjacent to the planar induction element when the planar induction element is received in the recess.
The cartridge of claim 8, wherein the susceptor comprises a first sheet providing the first planar surface and a second sheet providing the second planar surface, the first sheet separate from the second sheet; and optionally wherein a first thickness of the first sheet is in the range of one or more of 20 µm to 70 µm, 30 µm to 60 µm, and 40 µm to 55 µm, and / or a second thickness of the second sheet is in the range of one or more of 20 µm to 70 µm, 30 µm to 60 µm, and 40 µm to 55 µm.
An induction assembly for use with a cartridge in accordance with any of claims 1 to 9, the induction assembly comprising a planar induction element, the planar induction element operable to induce current flow in a susceptor of the cartridge to inductively heat the susceptor, wherein the induction assembly is configured to be received at least partially by a recess of the cartridge such that a plane defining the planar induction element is parallel to and offset from a planar surface of the susceptor in a direction perpendicular to the plane.
The induction assembly of claim 10, wherein the planar induction element comprises one of a flat spiral coil, and one or more conductive layers deposited upon a support.
The induction assembly of claim 10 or claim 11, wherein the induction assembly comprises a ferrite shield, wherein at least a portion of the ferrite shield is provided parallel and adjacent to the plane of the planar induction element, wherein the ferrite shield is positioned on an opposite side of the planar induction element to the planar surface of the susceptor when the planar induction element is received in the recess of the cartridge.
A control unit for use in an aerosol delivery system for generating an aerosol from an aerosol-generating substrate, the control unit comprising:
the induction assembly of any of claims 10 to 12;

a power supply for supplying power to the planar induction element; and

control circuitry for controlling the supply of power to the planar induction element, wherein the control circuitry is configured to drive the planar induction element to induce current flow in a susceptor to inductively heat the susceptor and so vaporise a portion of the aerosol generating substrate in the vicinity of the susceptor.
An aerosol delivery system for generating an aerosol from an aerosol generating substrate, the aerosol delivery system comprising:
the cartridge of any of claims 1 to 9; and

the control unit of claim 13.
A method of generating an aerosol from an aerosol generating substrate in an aerosol delivery system, the aerosol delivery system comprising a cartridge and a control unit, wherein the cartridge comprises a susceptor and a recess, and the control unit comprises a planar induction element, a power supply and control circuitry, the method comprising:
inserting the planar induction element into the recess to position a planar surface of the susceptor to be parallel to a plane defining the planar induction element and offset from the planar induction element in a direction perpendicular to the plane;

driving the planar induction element to induce current flow in the susceptor to inductively heat the susceptor and so vaporise a portion of the aerosol generating substrate in the vicinity of the susceptor.