RU2851125C1 - Electrically heated system generating aerosol (variations), and cartridge for use in an electrically heated system generating aerosol - Google Patents

Abstract

FIELD: smoking accessories.

SUBSTANCE: invention relates to an electrically heated aerosol generating system, a cartridge for use in an electrically heated aerosol generating system, and a current collector unit for an electrically heated aerosol generating system. An electrically heated aerosol generating system (variants) and a cartridge for it are proposed. The system comprises at least one induction coil (66); a power source (72) connected to at least one induction coil and capable of supplying alternating current to at least one induction coil to generate an alternating magnetic field; a housing (36) containing a reservoir (40) with a substrate (42) forming an aerosol; and a substantially flat current collector assembly (12). The current collector assembly (12) is configured to be heated by the alternating magnetic field and comprises a first current collector element (16), a second current-receiving element (18) and a wick element (20) communicating with the reservoir (40) via a fluid medium, wherein the first and second current-receiving elements (16, 18) are integral with or attached to the wick element (20). A space is formed between the first and second current-receiving elements (16, 18), with the wick element (20) located in this space and the reservoir (40) located outside this space.

EFFECT: provision of an effective and reliable induction heating system for aerosol generation, in which low-frequency alternating current can be used.

17 cl, 17 dwg

Description

The present invention relates to an electrically heated aerosol generating system, a cartridge for use in the electrically heated aerosol generating system, and a current collector (susceptor) unit for the electrically heated aerosol generating system.

In many known aerosol-generating systems, an aerosol-forming substrate is heated and evaporated to form a vapor. The vapor cools and condenses, forming an aerosol. In some aerosol-generating systems, such as electrically heated smoking systems, this aerosol is then inhaled by the user. Such electrically heated smoking systems are typically hand-held and comprise a power source, a storage portion for holding a supply of aerosol-forming substrate, and a heating element. The aerosol-forming substrate may be a liquid. In such cases, the aerosol-generating system may further comprise a wick element configured to draw the liquid aerosol-forming substrate from the storage portion into the heating element for heating.

Some aerosol-generating systems comprise an aerosol-generating device and a cartridge adapted for use with the device. In such systems, the aerosol-generating device is typically reusable and contains a power source. The cartridge is single-use and contains or forms a storage section that holds the aerosol-generating substrate. When the aerosol-generating substrate is exhausted, the cartridge is replaced. A heating element may be located within the cartridge.

Hand-held aerosol-generating systems incorporating an induction heating system have been proposed. Induction heating systems typically comprise at least one induction coil connected to a power source and a current-sensing (susceptor) element positioned in close proximity to the aerosol-generating substrate and within an alternating magnetic field. When the aerosol-generating system comprises an aerosol-generating device and a cartridge, the current-sensing (susceptor) element may form part of either the cartridge or the device.

Document CN 110037346 A describes an atomization unit of an electronic cigarette and an electronic cigarette in which the atomization unit is installed. The atomization unit comprises an atomization core sleeve, an oil guide cover, a U-shaped induction metal part, an oil guide cotton and an induction coil, wherein the oil guide cover is detachably mounted on the end of the atomization core sleeve, the oil guide cover is provided with a guide sleeve, the guide sleeve extends in a direction from the atomization core sleeve, the induction metal part is located in the atomization core sleeve, one end of the oil guide cotton is located in the induction metal part, the other end of the oil guide cotton is located in the guide sleeve, and the induction coil surrounds the atomization core sleeve.

The power source is configured to supply alternating current to an induction coil, which generates an alternating magnetic field that induces current flow in a current-receiving (suspender) element. When the alternating magnetic field penetrates the current-receiving (suspender) element, the current-receiving (suspender) element heats up, at least due to Joule heating from induced eddy currents in the current-receiver (suspender) and hysteresis losses. The heated current-receiving (suspender) element heats the aerosol-forming substrate, resulting in the release of volatile compounds from the aerosol-forming substrate, which cool to form an inhalable aerosol.

One advantage of induction heating systems is that the system's electrical components can be isolated from the aerosol-forming substrate and any generated aerosol. Another advantage is that the cartridge design can be simplified, as there is no need to provide an electrical connection to the device.

It would be desirable to provide an efficient and reliable induction heating system for aerosol generation and a system in which low frequency alternating current can be used.

According to the present invention, there is provided an electrically heated aerosol generating system. The system,

An aerosol generating system may comprise at least one induction coil. The aerosol generating system may comprise a power source. The power source may be connected to the at least one induction coil. The power source may be configured to provide alternating current to the at least one induction coil to create an alternating magnetic field. The aerosol generating system may comprise a housing that houses a reservoir with an aerosol-forming substrate. The aerosol generating system may comprise a substantially flat current-collecting (suspender) assembly. The current-collecting (suspender) assembly may be configured to be heated by an alternating magnetic field. The current-collecting (suspender) assembly may comprise a first current-collecting (suspender) element. The current-collecting (suspender) assembly may comprise a second current-collecting (suspender) element. The current-collecting (suspender) assembly may comprise a wick element. The wick element may be in fluid communication with the reservoir. The first and second current-collecting (suspender) elements may be integral with the wick element or attached to it. A space may be defined between the first and second current-collecting (suspender) elements. The wick element may occupy the space.

The reservoir may be located outside the space between the first and second current-collecting (suspending) elements. In other words, the current-collecting (suspending) unit may be located substantially outside the reservoir. In particular, each current-collecting (suspending) element of the current-collecting (suspending) unit may be located substantially outside the reservoir. Preferably, at least a portion of the major surfaces of the or each current-collecting unit is not in direct contact with the reservoir. Preferably, at least a portion of two opposing major surfaces of the current-collecting unit is in direct contact with air in an airflow passage in the system.

During operation, an alternating current is passed through at least one induction coil to create an alternating magnetic field, which induces a voltage in the first and second current-collecting (suspender) elements. The induced voltage causes current to flow in each of the first and second current-collecting (suspender) elements, and this current causes Joule heating of the first and second current-collecting (suspender) elements, which in turn heats the substrate forming the aerosol transported by the wick element. If the current-collecting (suspender) element is ferromagnetic, hysteresis losses in the current-collecting (suspender) element can also generate heat.

The aerosol-generating substrate may be a liquid. The reservoir may be configured to hold the liquid aerosol-generating substrate. The reservoir may have any suitable shape and size, depending on the requirements of the aerosol-generating system.

In some embodiments, the reservoir comprises a material with retention capacity for retaining a liquid aerosol-forming substrate. If the reservoir comprises multiple parts, the material with retention capacity may be located in one or more parts of the reservoir, or in all parts of the reservoir. The material with retention capacity may be a foam material, a sponge material, or a fiber assembly. The material with retention capacity may be formed from a polymer or copolymer. In one embodiment, the material with retention capacity is a spun polymer. The material with retention capacity may be formed from any of the materials described below as suitable for the wick element.

When the reservoir contains a material with retention capacity, the wick element may be in fluid communication with the material with retention capacity. The material with retention capacity may contact the current-collecting assembly. In particular, the material with retention capacity may be in contact with the wick element of the current-collecting assembly.

Because the wick element is in fluid communication with the reservoir, it can preferentially transport the liquid aerosol-forming substrate from the reservoir. Thus, a portion of the aerosol-forming substrate can be transported to the first and second current-collecting elements. The transport of the aerosol-forming substrate can be the result of capillary action within the wick element. Specifically, the wick element can be arranged to transport the aerosol-forming substrate from the reservoir across the major surfaces of the first and second current-collecting elements, which are attached to the wick element or are integral parts of it.

Providing a wick element improves wetting of the first and second current-collecting elements, thus increasing aerosol generation by the system. This allows current-collecting elements to be manufactured from materials that do not provide good wicking or wetting properties on their own.

Providing a wick element between the first and second current-collecting elements, which are integral to or attached to the wick elements, can, during operation, advantageously cause the aerosol-forming substrate to evaporate on the outer surfaces of the wick element, located closest to the current-collecting elements. Therefore, the generated vapor can be primarily generated at the interface between the current-collecting elements and the wick element. The generated vapor thus need not pass through the main portion of the wick element to exit the wick element, which can lead to cooling and possible condensation of the vapor. This arrangement can advantageously facilitate faster aerosol production after applying alternating current to the induction coil and can also be more efficient and consume less energy.

The wick element, occupying the space between the first and second current-collecting elements, can essentially mean that during operation, the wick element is heated from two opposite sides. This can increase the amount of aerosol-forming substrate that evaporates over a given time, compared to a current-collecting unit containing only one current-collecting element.

Preferably, the current-collecting unit can be configured to hold only a small volume of liquid aerosol-forming substrate, sufficient for a single user puff. This is advantageous because it allows for rapid evaporation of a small volume of liquid with minimal heat loss to other system components or to the liquid aerosol-forming substrate, which does not evaporate. Preferably, the current-collecting unit or the heating area of the current-collecting unit can hold between 2 and 10 milliliters of liquid aerosol-forming substrate.

The reservoir may be configured to hold at least twice as much aerosol-forming substrate as the current-collecting unit. Preferably, the reservoir may be configured to hold at least 5, 10, 15, or even 20 times as much aerosol-forming substrate as the current-collecting unit. The reservoir may be configured to hold sufficient aerosol-forming substrate for at least 10 puffs, preferably at least 20 puffs, even more preferably at least 30 puffs. The reservoir may be configured to hold sufficient aerosol-forming substrate for at least 2 smoking sessions, preferably at least 3, 4, 5, or 6 smoking sessions. Each smoking session may contain at least 4 puffs, preferably at least 5 puffs, even more preferably at least 6 puffs. This contrasts with the current-receiving unit, which, as noted above, may be configured to hold only a sufficient amount of aerosol-forming liquid substrate for a single user puff at any given time.

The first and second current-collecting elements may be fluid-permeable. As used herein, a "fluid-permeable" element means an element that allows liquid or gas to permeate therethrough. A fluid-permeable current-collecting element may advantageously allow vaporized aerosol-forming substrate to escape through the current-collecting element. Thus, vapor from the aerosol-forming substrate generated in the region of the wick element immediately adjacent to the current-collecting element may escape through the current-collecting element without having to pass through the wick element.

As used herein, "current collector" means an element capable of heating when exposed to an alternating magnetic field. The current collector typically heats by at least one of Joule heating, induced eddy currents in the current collector, and hysteresis losses. Possible materials for current collectors include graphite, molybdenum, silicon carbide, stainless steel, niobium, aluminum, and essentially any other conductive elements. Advantageously, the first and second current collectors may be ferrite elements. The material and geometry of the current collectors may be selected to provide the desired electrical resistance and heat dissipation. Preferably, the first and second current collectors comprise AISI 430 stainless steel.

Preferably, the first and second current-collecting elements can have a relative permeability of 1 to 40,000. If eddy currents are desired for the majority of the heating, a material with lower permeability can be used, and if hysteresis effects are desired, a material with higher permeability can be used. Preferably, the material has a relative permeability of 500 to 40,000. This can ensure efficient heating.

As used herein, "alternating current" means a current that periodically reverses direction. Passing alternating current through at least one induction coil causes the at least one induction coil to generate an alternating magnetic field. The alternating magnetic field may have any suitable frequency to heat the heating region of the current-receiving element located within the alternating magnetic field. Suitable alternating current frequencies may range from 100 kilohertz (kHz) to 30 megahertz (MHz). Alternating current may have a frequency from 100 kilohertz (kHz) to 1 megahertz (MHz).

The thickness of each of the current-collecting elements is predominantly of an order of magnitude similar to the depth of the surface layer of the current-collecting element material at the operating frequency of the system.

Preferably, the current collector assembly has a thickness no more than ten times greater than the surface layer depth of the current collector element material at the operating frequency. This ensures that each current collector element has a sufficiently low mass, and therefore the time required for the current collector elements to reach a temperature suitable for evaporation of the aerosol-forming substrate is short. When an alternating magnetic field penetrates the current collector element from opposite sides, each current collector element can preferably have a thickness at least twice the surface layer depth of the current collector element material at the operating frequency. This minimizes the interaction of surface effects on opposite sides of the current collector element.

Each current-collecting element may be no more than two millimeters thick. Preferably, the thickness of each current-collecting element may be one millimeter.

The first and second current-collecting elements may comprise or consist of conductive threads. The first and second current-collecting elements may comprise or consist of a mesh, a flat spiral coil, fibers, or fabric of conductive threads. As used herein, the term "mesh" encompasses grids and matrices of threads with spaces between them. The term "mesh" also includes woven or non-woven materials. During operation, the evaporated substrate, which forms the aerosol, may preferentially exit the wick element through the spaces between the conductive threads.

Although the wick element can transport the aerosol-forming substrate from the reservoir to the first and second current-collecting elements via capillary action, the conductive threads can also induce capillary action in the spaces between the mesh threads to wet the first and second current-collecting elements. Wetting the first and second current-collecting elements can advantageously increase the contact area between the conductive threads of the current-collecting element and the aerosol-forming substrate.

The conductive threads may have a diameter of 40 to 60 micrometers, preferably 45 to 55 micrometers, and even more preferably 50 micrometers. The mesh size of the conductive thread mesh may range from 60 to 150 micrometers, preferably 50 to 70 micrometers, even more preferably 60 to 65 micrometers, and most preferably 63 micrometers. These dimensions may be suitable to ensure capillary action within the first and second current-collecting elements.

The mesh's open area percentage, which is the ratio of the area of the interstices to the total mesh area, is preferably between 25 and 56 percent. The mesh can be formed using various types of woven or lattice structures. Alternatively, the threads may consist of a matrix of threads arranged parallel to one another.

The filaments can be formed by etching a sheet material such as foil. This can be particularly advantageous if the heating element contains a matrix of parallel filaments. If the heating element contains a mesh or woven fabric made of filaments, the filaments can be produced individually and knitted together.

Preferably, the mesh is sintered. Sintering the mesh advantageously creates electrical connections between the threads running in different directions. In particular, if the mesh contains one or more woven and nonwoven materials, it is preferable for the mesh to be sintered to create electrical connections between the overlapping threads.

Alternatively, the first and second current-collecting elements may comprise or consist of perforated foil. During operation, the evaporated aerosol-forming substrate may primarily exit the wick element through the perforations in the perforated foil. The perforations may be evenly distributed across the first and second current-collecting elements. Each current-collecting element may be perforated to allow vapor to exit the current-collecting unit or to allow the entry of liquid aerosol-forming substrate.

Alternatively, each current-collecting element may be printed or otherwise applied to the wick element as a film or multiple tracks. Each current-collecting element may comprise or consist of a conductive material applied directly to the wick element.

The electrically conductive material of the first or second current-collecting element may be applied to the wick element in the form of a plurality of tracks. During operation, the evaporated substrate, forming an aerosol, may preferentially exit the wick element through gaps or spaces between the tracks. The plurality of tracks of each current-collecting element may be preferentially distributed over the surface of the wick element to ensure substantially uniform heating across the entire surface. For example, the width of each track and the distance between them may be substantially the same for each of the plurality of tracks. The plurality of tracks of each current-collecting element may comprise a first set of tracks parallel to one another. The plurality of tracks may further comprise a second set of tracks perpendicular to the first set of tracks and overlapping the first set of tracks. The first and second sets of tracks may together form a grid-like structure.

The wick element may comprise a capillary material. A capillary material is a material capable of transporting liquid from one end of the material to the other by capillary action. The capillary material may have a fibrous or spongy structure. The capillary material preferably comprises a bundle of capillaries. For example, the capillary material may comprise a plurality of fibers or filaments, or other tubes with narrow channels. The fibers or filaments may be generally aligned to transport the liquid aerosol-forming substrate across the main surface of each of the current-receiving elements. In some embodiments, the capillary material may comprise a sponge-like or foam-like material. The structure of the capillary material may form a plurality of small openings or tubes through which the liquid aerosol-forming substrate may be transported by capillary action. If the current-receiving elements comprise gaps or openings, the capillary material may extend into the gaps or openings in the current-receiving element. Current-collecting elements can draw the liquid aerosol-forming substrate into gaps or openings by capillary action. The wick element may comprise or consist of an electrically insulating material. The wick element may comprise a non-metallic material. The wick element may comprise a hydrophilic material or an oleophilic material. This may advantageously facilitate the transport of the aerosol-forming substrate through the wick element.

The wick element may preferably comprise or consist of cotton, viscose or glass fibre.

Alternatively, the wick element may comprise or consist of a porous ceramic material. Wick elements comprising porous ceramic materials may be particularly advantageous if one or both current-collecting elements contain an electrically conductive material printed or otherwise applied to the wick element. A wick element comprising a porous ceramic material may be a suitable substrate for manufacturing processes involving the printing or deposition of an electrically conductive material.

The first current-collecting element of the current-collecting unit can be electrically isolated from the second current-collecting element of the current-collecting unit.

A substantially flat current-collecting unit may extend parallel to the first plane. The aerosol-generating system may comprise a first induction coil and a second induction coil, wherein the first induction coil is located on a first side of the current-collecting unit and extends parallel to the first plane, and the second induction coil is located on a second side of the current-collecting unit opposite the first side and extends parallel to the first plane. The current-collecting unit may be located between the first induction coil and the second induction coil. The aerosol-generating system may comprise a control circuit connected to the first and second induction coils and configured to provide alternating current to the first and second induction coils. Advantageously, the current-collecting unit may be substantially equidistant from the first and second induction coils.

This arrangement can ensure efficient heating of the current-collecting elements of the current-collecting unit and balance the forces acting on the current-collecting unit under the influence of the magnetic fields generated by the first and second induction coils. Preferably, the control circuit is configured to provide current to the induction coils such that the first induction coil exerts an equal and opposite force on the current-collecting unit relative to the second induction coil. The first induction coil can generate a magnetic field opposite to the magnetic field generated by the second induction coil.

In this context, a flat current collector is a current collector whose length and width are significantly greater than its thickness. The length-to-width ratio can range from 0.4 to 1.6. Preferably, the length-to-width ratio can range from 0.6 to 1.4. Even more preferably, the length-to-width ratio can range from 0.8 to 1.2.

The length and width directions are orthogonal to each other and define the first plane. The thickness runs orthogonally to the first plane. A flat current-collecting element may have two opposing primary surfaces running in a plane parallel to the first plane. One or both primary surfaces are predominantly flat.

In this context, a current-collecting unit that is substantially equidistant from the first and second induction coils means that the shortest distance between the first induction coil and the current-collecting unit is between 0.8 and 1.2 times the shortest distance between the second induction coil and the current-collecting unit. Preferably, the shortest distance between the first induction coil and the current-collecting unit is between 0.85 and 1.15 times the shortest distance between the second induction coil and the current-collecting unit. More preferably, the shortest distance between the first induction coil and the current-collecting unit is between 0.9 and 1.1 times the shortest distance between the second induction coil and the current-collecting unit. Even more preferably, the shortest distance between the first induction coil and the current-collecting unit is substantially identical to the shortest distance between the second induction coil and the current-collecting unit.

The first and second induction coils are typically flat coils. In this context, a flat coil refers to a coil lying in a plane perpendicular to the coil's winding axis. Flat coils can be compact. Flat coils can also lie in a plane parallel to the first plane.

The system can be designed such that at least one induction coil provides a magnetic field at the current-collecting element perpendicular to the first plane. The system can be designed such that the first and second induction coils provide a magnetic field at the current-collecting element perpendicular to the first plane. This allows for efficient heating of the current-collecting element. The inventors also found that this arrangement facilitates efficient heating of the first and second current-collecting elements, allowing the use of lower AC frequencies. For example, AC with a frequency of 100 kHz to 1 MHz can be used. Lower frequencies may allow for the use of simpler electronics to supply the AC current.

The first and second flat induction coils may have any shape, but in one preferred embodiment, each of the flat induction coils is rectangular. The flat induction coils may advantageously have a size and shape corresponding to the heating region of the current-receiving element. The first induction coil may have the same number of turns as the second induction coil. The first induction coil may have the same size and shape as the second induction coil. The first induction coil may be substantially identical to the second induction coil. The first induction coil may have the same electrical resistance as the second induction coil. The first induction coil may have the same inductance as the second induction coil.

In one embodiment, the induction coils are electrically connected to form a single conductive path, with the first induction coil wound in the opposite direction to the second induction coil. The first and second induction coils can then be supplied with the same alternating electric current.

In another embodiment, the first induction coil is wound in the same direction as the second induction coil. The control circuit is configured to provide a current in the first induction coil that is out of phase with the current supplied to the second induction coil.

Advantageously, the aerosol-generating system may comprise one or more flow concentrators configured to retain the magnetic field generated by the induction coils. The one or more flow concentrators may be configured to concentrate the magnetic field on the current-collecting unit, preferably perpendicular to the first plane.

Each current-receiving element of the current-receiving assembly may comprise a heating region and at least one fastening region. The first and second current-receiving elements may have the same shape. The heating region and at least one fastening region of the first current-receiving element may correspond to the heating region and at least one fastening region of the second current-receiving element. The features of the heating region or at least one fastening region described with respect to one of the first and second current-receiving elements may equally apply to the other of the first and second current-receiving elements.

The heating region may be a region of the current-receiving element that is capable of being heated to a temperature required for evaporation of the aerosol-forming substrate upon penetration of a suitable alternating magnetic field therein.

The heating region may comprise a first material, which is a magnetic material that heats when an alternating magnetic field penetrates it. The term "magnetic material" is used herein to describe a material capable of interacting with a magnetic field, including both paramagnetic and ferromagnetic materials. The first material may be any suitable magnetic material capable of heating when an alternating magnetic field penetrates it. In some preferred embodiments, the first material comprises ferritic stainless steel. Suitable ferritic stainless steels include AISI 400 series stainless steels, such as AISI 409, 410, 420, and 430 stainless steels.

In some preferred embodiments, the heating region consists of a first material. However, in other embodiments, the heating region comprises the first material and one or more other materials. If the heating region comprises the first material and one or more other materials, the heating region may comprise any suitable proportion of the first material. For example, the heating region may comprise at least 10% by weight of the first material, or at least 20% by weight of the first material, or at least 30% by weight of the first material, or at least 40% by weight of the first material, or at least 50% by weight of the first material, or at least 60% by weight of the first material, or at least 70% by weight of the first material, or at least 80% by weight of the first material, or at least 90% by weight of the first material.

At least one fastening region of each of the current-receiving elements is a region that is configured to contact the holder of the current-receiving assembly. At least one fastening region may be in contact with the holder of the current-receiving assembly. As used herein, the term "contact" means both direct contact and indirect contact. The heating region may be configured to heat to a substantially higher temperature than the fastening region in the presence of an alternating magnetic field. This may be caused by differences in the material between the heating region and the fastening region, geometric differences between the heating region and the fastening region, or differences in both the material and the geometry. The heating region may be located in the space directly between the first and second induction coils, and the fastening region may be located outside the space directly between the first and second induction coils. The fastening region may have a smaller width or length in the first plane than the heating region.

Preferably, at least one fastening area is in direct contact with the current collector holder. As used herein, the term "direct contact" means contact between two components without any intervening material, such that the surfaces of the two components touch each other.

At least one attachment region of each current-collecting element may be in indirect contact with the current-collecting element holder. In the context of this document, the term "indirect contact" is used to denote contact between two components via one or more intermediate materials positioned between the two components such that the surfaces of the two components do not contact each other. For example, at least one attachment region of each current-collecting element is in indirect contact with the current-collecting element holder when an adhesive element is provided between the surface of at least one attachment region and the surface of the current-collecting element holder.

In some preferred embodiments, at least one fastening region may extend into the reservoir. In some preferred embodiments, the heating region of each of the susceptor elements may be located outside the reservoir. Advantageously, locating each of the susceptor elements substantially outside the reservoir, and especially locating the heating region of each of the susceptor elements outside the reservoir, can ensure that the aerosol-forming substrate is heated sufficiently to release volatile compounds only after the aerosol-forming substrate has been moved outside the reservoir. This can facilitate the release of volatile compounds from the aerosol-generating system.

At least one attachment region of each of the current-collecting elements may comprise a second material. The second material may be a non-magnetic material. The term "non-magnetic material" is used herein to describe a material that does not interact with a magnetic field and does not heat up when exposed to an alternating magnetic field. The second material may be any suitable non-magnetic material. In some embodiments, the second material is a non-magnetic metal. For example, the second material may be a non-magnetic austenitic stainless steel. Suitable austenitic stainless steels include AISI 300 series stainless steels, such as AISI Types 304, 309, and 316 stainless steels.

The current collector holder may be in contact with the second material in at least one attachment region of each current collector element. The current collector holder may contact each current collector element only on the second material. Advantageously, providing contact between the current collector holder and the current collector element on the second material can help minimize heat transfer from the current collector element to the current collector holder.

In some embodiments, the second material is a non-metallic material. For example, the second material may be a ceramic material.

In some embodiments, the second material is an electrically conductive material. As used herein, an "electrically conductive" material means a material having a volume resistivity at 20 degrees Celsius (°C) of less than about 1× ^10-5 ohm-meters (Ohm⋅m), typically from about 1× ^10-5 ohm-meters (Ohm⋅m) to about 1× ^10-9 ohm-meters (Ohm⋅m). Suitable conductive materials include metals, alloys, conductive ceramics, and conductive polymers.

Suitable conductive materials may include gold and platinum.

In some embodiments, the second material is an electrically insulating material. Advantageously, the electrically insulating second material can help minimize heat transfer from each of the current-receiving elements to the current-receiving assembly holder. As used herein, "electrically insulating" material means a material having a volume resistivity at 20 degrees Celsius (°C) greater than about 1× ¹⁰⁶ ohm-meters (Ohm⋅m), typically from about 1× ¹⁰⁹ ohm-meters (Ohm⋅m) to about 1× ¹⁰²¹ ohm-meters (Ohm⋅m). Suitable electrically insulating materials include glass, plastics, and certain ceramic materials.

In some embodiments, the second material is a thermally insulating material. A predominantly thermally insulating second material can help minimize heat transfer from each of the current-receiving elements to the current-receiving assembly holder. As used herein, the term "thermally insulating" refers to a material having a bulk thermal conductivity of less than 5 watts per meter Kelvin (mW/(m⋅K)) at a temperature of 23°C and a relative humidity of 50%, as measured using the modified transient plate source (MTPS) method.

In some embodiments, the second material is a thermally conductive material. As used herein, the term "thermally conductive" refers to a material having a bulk thermal conductivity of at least about 10 watts per meter Kelvin (mW/(m⋅K)) at 23°C and 50% relative humidity, as measured using the modified transient plate source (MTPS) method.

In some embodiments, the second material may be a hydrophilic material. In some embodiments, the second material may be an oleophilic material. Advantageously, providing a hydrophilic second material or an oleophilic second material can promote the transport of the aerosol-forming substrate through each of the current-receiving elements.

In some embodiments, the second material comprises a cellulosic material. For example, the second material may comprise viscose.

In some preferred embodiments, at least one fastening region of each of the current-receiving elements comprises a second material. However, in other embodiments, at least one fastening region comprises a second material and one or more other materials. If at least one fastening region comprises a second material and one or more other materials, then the at least one fastening region may comprise any suitable proportion of the second material. For example, at least one fastening region of a current-receiving element may comprise: at least 10 percent by weight of the second material, or at least 20 percent by weight of the second material, or at least 30 percent by weight of the second material, or at least 40 percent by weight of the second material, or at least 50 percent by weight of the second material, or at least 60 percent by weight of the second material, or at least 70 percent by weight of the second material, or at least 80 percent by weight of the second material, or at least 90 percent by weight of the second material.

At least one fastening region of each current-collecting element may comprise a first material. However, at least one fastening region comprises a smaller proportion of the first material than the heating region. The proportion by weight of the first material in the heating region may be greater than the proportion by weight of the first material in at least one fastening region. For example: the heating region of the current-receiving element may contain at least 90 percent by weight of the first material, and at least one area of fastening of the current-receiving element may contain less than 10 percent by weight of the first material, or the heating region of the current-receiving element may contain at least 80 percent by weight of the first material, and at least one area of fastening of the current-receiving element may contain less than 20 percent by weight of the first material, or the heating region of the current-receiving element may contain at least 70 percent by weight of the first material, and at least one area of fastening of the current-receiving element may contain less than 30 percent by weight of the first material, or the heating region of the current-receiving element may contain at least 60 percent by weight of the first material, and at least one area of fastening of the current-receiving element may contain less than 40 percent by weight of the first material, or the heating region of the current-receiving element may contain at least 50 percent by weight of the first material, and at least one area of fastening of the current-receiving element may contain less 50 percent by weight of the first material.

At least one fastening region of each of the current-collecting elements may contain: 90 percent or less by weight of the first material, or 80 percent or less by weight of the first material, or 70 percent or less by weight of the first material, or 60 percent or less by weight of the first material, or 50 percent or less by weight of the first material, or 40 percent or less by weight of the first material, or 30 percent or less by weight of the first material, or 20 percent or less by weight of the first material, or 10 percent or less by weight of the first material.

At least one fastening region of each of the current-collecting elements may contain: at least 10 percent by weight of the second material and less than 90 percent by weight of the first material, or at least 20 percent by weight of the second material and less than 80 percent by weight of the first material, or at least 30 percent by weight of the second material and less than 70 percent by weight of the first material, or at least 40 percent by weight of the second material and less than 60 percent by weight of the first material, or at least 50 percent by weight of the second material and less than 50 percent by weight of the first material, or less than 60 percent by weight of the second material and less than 40 percent by weight of the first material, or at least 70 percent by weight of the second material and less than 30 percent by weight of the first material, or at least 80 percent by weight of the second material and less than 20 percent by weight of the first material, or at least 90 percent by weight of the second material and less than 10 percent by weight of the first material.

The heating region of each of the current-receiving elements may comprise a second material. For example, the heating region may comprise: 90 percent or less by weight of the second material, or 80 percent or less by weight of the second material, or 70 percent or less by weight of the second material, or 60 percent or less by weight of the second material, or 50 percent or less by weight of the second material, or 40 percent or less by weight of the second material, or 30 percent or less by weight of the second material, or 20 percent or less by weight of the second material, or 10 percent or less by weight of the second material.

The heating region of each of the current-collecting elements may contain: at least 10 percent by weight of the first material and less than 90 percent by weight of the second material, or at least 20 percent by weight of the first material and less than 80 percent by weight of the second material, or at least 30 percent by weight of the first material and less than 70 percent by weight of the second material, or at least 40 percent by weight of the first material and less than 60 percent by weight of the second material, or at least 50 percent by weight of the first material and less than 50 percent by weight of the second material, or at least 60 percent by weight of the first material and less than 40 percent by weight of the second material, or at least 70 percent by weight of the first material and less than 30 percent by weight of the second material, or at least 80 percent by weight of the first material and less than 20 percent by weight of the second material, or at least 90 percent by weight of the first material and less than 10 percent by weight of the second material.

The heating region may comprise any suitable proportion of the current-receiving element. For example, the heating region may comprise at least 90 percent of the current-receiving element's surface area, at least 80 percent of the current-receiving element's surface area, or at least 70 percent of the current-receiving element's surface area. The heating region may have any suitable size and shape to heat the aerosol-forming substrate at the rate necessary to generate the desired amount of inhalable aerosol.

At least one fastening region may comprise any suitable proportion of the current-receiving element. Typically, the at least one fastening region comprises a smaller proportion of the current-receiving element than the heating region. For example, the at least one fastening region may comprise 10 percent or less of the current-receiving element's surface area, or 20 percent or less of the current-receiving element's surface area, or 30 percent or less of the current-receiving element's surface area. The at least one fastening region may have any suitable size and shape to ensure a strong connection between the current-receiving element and the current-receiving assembly holder.

In some embodiments, at least one fastening region is located adjacent to the periphery of the heating region, wherein the heating region has a length and a width, and at least one fastening region has a length and a width. It is preferable that the length of at least one fastening region is less than the length of the heating region. In some embodiments, the length of at least one fastening region is no more than half the length of the heating region. In some embodiments, the length of at least one fastening region is no more than a quarter of the length of the heating region. It is preferable that the width of at least one fastening region is less than the width of the heating region. In some embodiments, the width of at least one fastening region is no more than half the width of the heating region. In some embodiments, the width of at least one fastening region is no more than a quarter of the width of the heating region.

In some embodiments, at least one attachment region of each of the current-collecting elements is secured to the current-collecting assembly holder. The at least one attachment region may be secured to the current-collecting assembly holder using adhesive.

At least one attachment region of each current-receiving element may be located in any suitable position relative to the heating region of each current-receiving element. In some preferred embodiments, at least one attachment region of each current-receiving element is located on the periphery of the corresponding current-receiving element. For example, at least one attachment region may be located on one side of the current-receiving element.

In some preferred embodiments, at least one attachment region comprises a plurality of attachment regions. Each current-collecting element may comprise any suitable number of attachment regions. For example, each current-collecting element may comprise one, two, three, four, five, or six attachment regions. Advantageously, providing a current-collecting element with multiple attachment regions may allow the current-collecting element holder to provide more reliable support for the current-collecting element compared to a current-collecting element having a single attachment region.

In some embodiments, the plurality of fastening regions may comprise a first fastening region and a second fastening region, wherein the first fastening region is located on one side of the corresponding current-receiving element, and the second fastening region is located on the same side of the current-receiving element as the first fastening region. In some of these embodiments, the first fastening region is located at the first end of the current-receiving element, and the second fastening region is located at the second end of the current-receiving element, opposite the first end.

In some embodiments, the plurality of fastening regions comprise a first fastening region and a second fastening region, wherein the first fastening region is located on the first side of the current-receiving element, and the second fastening region is located on the second side of the current-receiving element, opposite the first side. In some of these embodiments, the heating region has a length, and the first fastening region and the second fastening region are located in the same position along the length of the heating region. In some of these embodiments, the first fastening region and the second fastening region are located at one end of the current-receiving element. In some of these embodiments, the heating region has a length, and the first fastening region and the second fastening region are located in the center along the length of the heating region. In some of these embodiments, the heating region has a length, and the first fastening region and the second fastening region are located in different positions along the length of the heating region. In some of these embodiments, the first fastening region is located at the first end of the current-receiving element, and the second fastening region is located at the second end of the current-receiving element, opposite the first end.

In some preferred embodiments, the plurality of fastening regions comprise a first fastening region and a second fastening region, wherein the second fastening region is located opposite the first fastening region.

In some preferred embodiments, the plurality of fastening regions comprises: a first pair of fastening regions located at the first end of the current-receiving element on opposite sides of the current-receiving element; and a second pair of fastening regions located at the second end of the current-receiving element on opposite sides of the current-receiving element, wherein the second end of the current-receiving element is located opposite the first end.

In some embodiments, the plurality of fastening regions comprises a plurality of pairs of fastening regions, each pair of fastening regions comprises a first fastening region located on the first side of the current-receiving element, and a second fastening region located on the second side of the current-receiving element, wherein the second side of the current-receiving element is opposite the first side of the current-receiving element.

In some embodiments, the plurality of fastening regions comprises a plurality of pairs of fastening regions, each pair of fastening regions comprises a first fastening region and a second fastening region, wherein the second fastening region is located opposite the first fastening region.

In cases where the current-collecting element comprises a mesh, the heating region may comprise filaments of a first material. In some embodiments, the heating region may comprise filaments of a first material and filaments of a second material. The heating region may comprise filaments of the first material in a first direction and filaments of the second material in a second direction distinct from the first direction.

If the current-collecting element comprises a mesh, at least one fastening region may comprise threads of a second material. In some embodiments, at least one fastening region may comprise threads of a first material and threads of a second material. At least one fastening region may comprise threads of the first material in a first direction and threads of the second material in a second direction different from the first direction.

If the current-collecting element contains a mesh, the mesh may be woven. Woven mesh contains threads in the weft direction and threads in the warp direction.

If the current collecting element comprises a woven mesh, at least one fastening region may comprise threads of the second material in the weft direction. The current collecting element holder may be in contact with the current collecting element in at least one fastening region on threads extending in the weft direction.

The current collector holder may be in contact with the current collector element in at least one fastening region only on the threads running in the weft direction and not in contact with the threads running in the warp direction. Advantageously, the formation of the threads running in the weft direction from the second material in at least one fastening region can reduce heat transfer from the current collector element to the current collector holder compared to a current collector element having threads in the weft direction formed from the first material in at least one fastening region.

If the current collecting element comprises a woven mesh, then at least one fastening region may comprise threads from a first material in the weft direction and threads from a second material in the warp direction, and at least one fastening region may comprise threads from a second material in the weft direction and threads from a second material in the warp direction.

If the current collecting element comprises a woven mesh, then at least one fastening region may consist of threads from a first material in the weft direction and threads from a second material in the warp direction, and at least one fastening region may consist of threads from a second material in the weft direction and threads from a second material in the warp direction.

If each of the current-collecting elements comprises a woven mesh, then at least one fastening region may comprise threads from a first material in the warp direction and threads from a second material in the weft direction, and at least one fastening region may comprise threads from a second material in the warp direction and threads from a second material in the weft direction.

If each of the current collecting elements comprises a woven mesh, then at least one fastening region may consist of threads from a first material in the warp direction and threads from a second material in the weft direction, and at least one fastening region may consist of threads from a second material in the warp direction and threads from a second material in the weft direction.

If each of the current-collecting elements comprises a woven mesh, then at least one fastening region may comprise threads from the first material in the weft direction and threads from the first material in the warp direction, and at least one fastening region may comprise threads from the first material in the weft direction and threads from the second material in the warp direction.

If each of the current collecting elements comprises a woven mesh, then at least one fastening region may consist of threads from the first material in the weft direction and threads from the first material in the warp direction, and at least one fastening region may consist of threads from the first material in the weft direction and threads from the second material in the warp direction.

If each of the current collecting elements comprises a woven mesh, then at least one fastening region may comprise threads from the first material in the warp direction and threads from the first material in the weft direction, and at least one fastening region may comprise threads from the first material in the warp direction and threads from the second material in the weft direction.

If each of the current collecting elements comprises a woven mesh, then at least one fastening region may consist of threads from the first material in the warp direction and threads from the first material in the weft direction, and at least one fastening region may consist of threads from the first material in the warp direction and threads from the second material in the weft direction.

Preferably, the aerosol-generating system may further comprise an airflow passage extending between the air inlet and the air outlet. The air outlet may be located in the mouthpiece of the system. During operation, the user of the system may inhale through the mouthpiece.

A portion of the current-collecting assembly may be located within an airflow passage. Airflow in the airflow passage may pass over the surface of the first current-collecting element and the surface of the second current-collecting element. The airflow in the airflow passage may pass over the heating region of the first and second current-collecting elements. Thus, during operation, the aerosol-forming substrate, which evaporated at the boundary between the first and second current-collecting elements and the wick element, may preferentially pass through the first and second current-collecting elements directly into the airflow passage. The vapor may condense, forming an aerosol in the airflow passage. The aerosol may be discharged from the aerosol-generating system through an air outlet. The air outlet may be provided at the mouthpiece end of the aerosol-generating system, through which the generated aerosol may be drawn by the user.

The wick element may be in fluid communication with the reservoir, as a portion of the wick element extends into the reservoir. The reservoir may comprise a fluid channel extending toward the current-collecting assembly. The liquid substrate forming the aerosol may flow through this channel toward the current-collecting assembly. At least a portion of the wick element may extend into the channel. As described above, at least one attachment region of each current-collecting element may extend into the reservoir.

The housing may comprise an inner wall and an outer wall such that the inner passage is defined by the inner wall. The inner passage may be surrounded by a space defined between the inner wall and the outer wall. The space surrounding the inner passage may be an annular space.

The airflow passage may be at least partially defined by an internal passage. The reservoir may be at least partially defined by the space surrounding the internal passage. In this arrangement, at least a portion of the airflow passage may extend through the reservoir.

Alternatively, the reservoir may be at least partially defined by an internal passage, and the air flow passage may be at least partially defined by a space surrounding the internal passage.

If the internal passage at least partially defines one of the airflow channel or the reservoir, and the space around the internal passage at least partially defines the other, this advantageously results in a compact aerosol-generating system. This also allows for the system to be symmetrical and balanced, which is advantageous when the system is hand-held. Furthermore, this arrangement places the airflow channel in close proximity to the reservoir, allowing the reservoir to exert a cooling effect on the air in the airflow channel, which can promote aerosol formation in the airflow channel.

As described above, the aerosol-generating system may comprise a susceptor holder on which the susceptor is mounted. At least one attachment region of the first and second susceptor elements may contact the holder. The susceptor holder may be tubular and have at least one side wall. The susceptor may be mounted through at least one opening in the side wall. The susceptor may be mounted through at least two openings in the side wall.

The current collecting unit holder may be configured to withstand temperatures to which the current collecting unit is raised to heat the aerosol-forming substrate.

The current collector holder may be formed from any suitable material capable of withstanding the temperatures to which the current collector is raised to heat the aerosol-forming substrate. Preferably, the current collector holder comprises a thermally insulating material. Advantageously, forming the current collector holder from a thermally insulating material can minimize heat transfer from the current collector element to the current collector holder. Preferably, the current collector holder comprises an electrically insulating material. The current collector holder may be formed from a durable material. The current collector holder may be formed from a liquid-impermeable material. The current collector holder may be formed from a moldable plastic material, such as polypropylene (PP) or polyethylene terephthalate (PET).

The current collector holder can be of any suitable shape and size.

At least one side wall of the current collector holder may form at least a portion of the inner wall of the housing. In this case, at least one side wall of the housing may define a portion of the internal passage. The space between the inner wall and the outer wall may be at least partially defined between at least one side wall and the outer wall of the housing. In some preferred embodiments, the current collector holder is tubular.

In some embodiments, the current-collecting unit extends into the internal passage of the current-collecting holder. In some preferred embodiments, the first and second current-collecting elements extend into the internal passage of the current-collecting holder. The first and second current-collecting elements may extend through the internal passage of the current-collecting unit holder. If the first and second current-collecting elements extend through the internal passage of the current-collecting holder, the first and second current-collecting elements may comprise a first attachment region on a first side of each current-collecting element in contact with the current-collecting holder and a second attachment region on a second side of each current-collecting element, opposite the first side, in contact with the current-collecting holder. Advantageously, the arrangement of the current-collecting element for contact with the current-collecting holder from opposite sides may allow the current-collecting holder to securely fix the current-collecting element in the cartridge.

The internal passage may extend substantially along the longitudinal axis. In some embodiments, the current-collecting assembly is substantially flat, and the current-collecting assembly extends parallel to the longitudinal axis. In some embodiments, the current-collecting assembly is substantially flat, and the current-collecting assembly extends perpendicular to the longitudinal axis.

In some embodiments, the internal passage of the current collector holder may form part of the air passage of the cartridge, and the space surrounding the internal passage, defined between the current collector holder and the outer housing of the system, may form part of the reservoir. In these embodiments, the heating region of the current collector element may be located within the internal passage of the current collector holder, and at least one fastening region may be located within the space.

In some embodiments, the internal passage of the current collector holder may form part of the cartridge reservoir, and the space around the internal passage, defined between the current collector holder and the outer housing of the system, may form part of the air passage. In these embodiments, at least one current collector element attachment region may extend into the internal passage of the current collector holder, and the heating region may extend into the space.

The tubular holder of the current collector assembly may have an open end, such that the internal passage of the holder of the current collector assembly is open at least at one end. At least one side wall of the tubular holder of the current collector may define an opening between the ends of the tubular holder of the current collector. At least one fastening region of the current collector element may extend into the opening of the tubular holder of the current collector. In some embodiments, when the current collector element comprises multiple fastening regions, at least one side wall of the tubular holder of the current collector defines a plurality of openings between the ends of the tubular holder of the current collector. In these embodiments, each fastening region of the current collector element may extend into one of the plurality of openings of at least one side wall of the tubular holder of the current collector.

The current collector holder may contain electrically insulating material. Suitable insulating materials include glass, plastic, and some ceramics.

The current collector holder may contain heat-insulating material.

A current collector holder can be molded onto the current collector. The molded holder can hold the first and second current collector elements and the wick element together so that the elements are secured together. The holder can be formed from a heat-resistant plastic material or a ceramic material. This allows the holder to support the current collector and ensure its strength.

The current collector assembly may be surrounded by a permeable electrically insulating coating. The coating may comprise or consist of a permeable ceramic material. The coating may be a ceramic coating. When the current collector assembly comprises a coating, the coating may hold the first and second current collector elements and the wick element together so that the elements are fixed together. The coating may advantageously improve the strength and stability of the current collector assembly. The coating may be provided instead of or in addition to the holder, as described above. The coating may comprise Al ₂ O ₃ or a silicon-based ceramic material. The coating may have a porosity of approximately 30 percent.

At least a portion of the current collector holder may comprise a porous or permeable material, such as a ceramic material. This portion may be a region of the current collector to which the current collector mounting area is attached. Aerosol-forming substrate from the reservoir may pass through this portion of the current collector holder to the current collector mounting areas. This advantageously provides a pathway for the aerosol-forming substrate to be transferred from the reservoir to the current collector and may increase the amount of aerosol-forming substrate delivered to the current collector.

The portion of the current collector holder containing the porous or _permeable material may comprise _Al2O3 or a silicon-based ceramic material. This portion may have a porosity of approximately 30 percent.

The current-collecting unit may further comprise a third current-collecting element and a second wick element, wherein the second wick element is positioned between the first current-collecting element and the third current-collecting element or the second current-collecting element and the third current-collecting element. Additional wick elements may be positioned between the current-collecting elements.

The aerosol-generating system may comprise a second susceptor assembly. The second susceptor assembly may be substantially similar to the first susceptor assembly in terms of structure. The second susceptor assembly may also be mounted on a susceptor assembly holder. The second susceptor assembly may be mounted on the same susceptor assembly holder as the first susceptor assembly. When the susceptor assembly holder is tubular, the second susceptor assembly may be mounted on the opposite side of the susceptor assembly holder relative to the first susceptor assembly. This arrangement may be particularly advantageous when the internal passage of the susceptor assembly holder forms part of the cartridge reservoir, and the annular space defined between the susceptor assembly and the outer housing forms at least part of the airflow passage. At least one attachment area of the current-collecting elements of each current-collecting assembly may extend into the internal passage, and the heating area may extend into the annular space. Thus, the heating area of the first and second current-collecting assemblies can be evenly distributed around the airflow channel, resulting in more uniform aerosol production.

The aerosol-generating system may contain additional susceptor assemblies. Each of these susceptor assemblies may be mounted on a susceptor holder. The susceptor assemblies may be mounted on the susceptor holder so that they are evenly distributed around the airflow passage.

An aerosol-forming substrate is one that can release volatile compounds that can form an aerosol. Volatile compounds can be released by heating the aerosol-forming substrate.

The aerosol-forming substrate may comprise a plant-based material. The aerosol-forming substrate may comprise tobacco. The aerosol-forming substrate may comprise a tobacco-containing material containing volatile tobacco flavor compounds that are released from the aerosol-forming substrate upon heating. Alternatively, the aerosol-forming substrate may comprise a non-tobacco-containing material. The aerosol-forming substrate may comprise a homogenized plant-based material. The aerosol-forming substrate may comprise a homogenized tobacco material. The aerosol-forming substrate may comprise at least one aerosol-forming substance. The aerosol-forming substance is any suitable known compound or mixture of compounds that, when used, promotes the formation of a dense and stable aerosol and is substantially resistant to thermal degradation at the operating temperature of the system. Suitable aerosol formers are well known in the art and include, but are not limited to, polyhydric alcohols such as triethylene glycol, 1,3-butanediol, and glycerol; esters of polyhydric alcohols such as glycerol mono-, di-, or triacetate; and aliphatic esters of mono-, di-, or polycarboxylic acids such as dimethyl dodecanedioate and dimethyl tetradecanedioate. Preferred aerosol formers are polyhydric alcohols or mixtures thereof, such as triethylene glycol, 1,3-butanediol, and most preferably glycerol. The aerosol-forming substrate may contain other additives and ingredients, such as flavoring agents.

The system may further comprise an electrical circuit connected to at least one induction coil and to a power source. The electrical circuit may comprise a microprocessor, which may be a programmable microprocessor, a microcontroller, or an application-specific integrated circuit (ASIC), or another electronic circuit capable of providing control. The electrical circuit may comprise additional electronic components. The electrical circuit may be configured to regulate the current supply to the induction coil. The current may be supplied to the induction coil continuously after activation of the system or may be supplied intermittently, for example, from puff to puff. The electrical circuit may advantageously comprise a DC-to-AC converter, which may comprise a class D or class E power amplifier. The control circuit may comprise additional electronic components. For example, in some embodiments, the control circuit may comprise any of the following: sensors, switches, display elements.

The aerosol-generating system may include a power source. The power source may be located within the system device. The power source may be a DC power source. The power source may be a battery. The battery may be a lithium-based battery, such as a lithium-cobalt, lithium-iron phosphate, lithium-titanate, or lithium-polymer battery. The battery may be a nickel-metal hydride battery or a nickel-cadmium battery. The power source may be another type of charge storage device, such as a capacitor. The power source may be rechargeable and capable of undergoing multiple charge and discharge cycles.

The power source may have a capacity sufficient to store sufficient energy for one or more user sessions of the aerosol-generating system; for example, the power source may have a capacity sufficient to continuously generate aerosol for approximately six minutes, which corresponds to the typical time required to smoke a conventional cigarette, or for a period of time that is a multiple of six minutes. In another example, the power source may have a capacity sufficient to support a specified number of puffs or individual activations of the atomization unit.

An aerosol-generating system may comprise an aerosol-generating device and a cartridge adapted for use with the device. The aerosol-generating device may comprise at least one induction coil, a power source, and a device housing. The device housing may be adapted to engage at least a portion of the cartridge when the cartridge is used with the aerosol-generating device. The cartridge may comprise a current-collecting unit. The cartridge may further comprise a cartridge housing. At least one induction coil may be located around or near the current-collecting unit when the cartridge is engaged with the aerosol-generating device. When the aerosol-generating system comprises first and second induction coils, the first induction coil may be located on the first side of the cartridge, and the second induction coil may be located on the second side of the cartridge when the cartridge is engaged with the aerosol-generating device. A portion of the cartridge containing the current collecting member of the cartridge may be located between the first and second induction coils when the cartridge is engaged with the aerosol generating device.

The cartridge housing may contain a housing defining a reservoir. The cartridge may contain a holder for the current-collecting unit.

The present invention also provides a cartridge for use in an electrically heated aerosol-generating system that includes an aerosol-generating device. The cartridge may be configured to be used with the device. The device may include a device body configured to engage at least a portion of the cartridge when the cartridge is used with the aerosol-generating device. The aerosol-generating device may include at least one induction coil. The aerosol-generating device may include a power source connected to the at least one induction coil. The power source may be configured to supply alternating current to the at least one induction coil such that the induction coil creates an alternating magnetic field inside the cartridge. The cartridge may include a cartridge body. The cartridge body may define a reservoir containing an aerosol-generating substrate. The cartridge may include a substantially flat current-collecting assembly. The substantially flat current-collecting assembly may extend parallel to the first plane. The current-collecting assembly may be configured to be heated by an alternating magnetic field. The current-collecting unit may comprise a first current-collecting element. The current-collecting unit may comprise a second current-collecting element. The current-collecting unit may comprise a wick element in fluid communication with the reservoir. The first and second current-collecting elements may be integral with the wick element or attached to it. A space may be defined between the first and second current-collecting elements. The wick element may occupy the space. The reservoir may be located outside the space.

The housing of the aerosol-generating device may be elongated. The housing of the aerosol-generating device may comprise any suitable material or combination of materials. Examples of suitable materials include metals, alloys, plastics, or composite materials containing one or more of these materials, or thermoplastic materials suitable for use in the food or pharmaceutical industries, such as polypropylene, polyetheretherketone (PEEK), and polyethylene. The material is preferably lightweight and non-fragile.

The housing of the aerosol-generating device may define a cavity for receiving a cartridge. The aerosol-generating device may comprise one or more air inlets. The one or more air inlets may draw ambient air into the cavity.

The aerosol-generating device may have a connecting end configured to connect the aerosol-generating device to a cartridge. The connecting end may comprise a cavity for receiving the cartridge.

The aerosol-generating device may have a distal end opposite the connecting end. The distal end may comprise an electrical connector configured to connect the aerosol-generating device to an electrical connector of an external power source for charging the aerosol-generating device's power source.

The cartridge may include an outer casing. The outer casing may be made of a durable material. The outer casing may be made of a liquid-impermeable material. The outer casing may be made of a moldable plastic material, such as polypropylene (PP) or polyethylene terephthalate (PET). The outer casing may be made of the same material as the current collector holder or may be made of a different material.

The current-collecting unit may be located within an outer housing. A current-collecting unit holder may be located within the outer housing. In some embodiments, the current-collecting unit holder may be formed as a single unit with the outer housing.

The cartridge's outer housing may define a portion of the reservoir. The outer housing may define the reservoir. The outer housing and reservoir may be formed as a single unit. Alternatively, the reservoir may be formed separately from the outer housing and located within the outer housing.

In some preferred embodiments, where the cartridge comprises an outer housing, a susceptor holder can secure the susceptor to the outer housing. Advantageously, providing the cartridge with a susceptor holder that secures the susceptor to the housing can separate the susceptor from the outer housing, so that the outer housing does not need to be designed to withstand the temperatures to which the susceptor rises to heat the aerosol-forming substrate. This can allow the cartridge to be manufactured from less durable and less expensive materials.

The cartridge may comprise two parts, a first part and a second part. The second part may be movable relative to the first part. The first and second parts of the cartridge may be movable relative to each other between a storage configuration and a use configuration. In the storage configuration, the susceptor assembly may be isolated from the aerosol-forming substrate. In the use configuration, the susceptor assembly may be in fluid communication with the aerosol-forming substrate.

The reservoir may comprise two parts, a first part and a second part. A seal may be provided between the first part and the second part. The seal may be positioned to prevent fluid communication between the first part of the reservoir and the second part of the reservoir. In other words, the seal may fluidly isolate the first part of the reservoir from the second part of the reservoir. In the storage configuration, the liquid aerosol-forming substrate may be retained in the first part of the reservoir. In the storage configuration, the seal may prevent the aerosol-forming substrate from flowing from the first part of the reservoir to the second part of the reservoir.

The first cartridge portion may comprise a first reservoir portion and a seal. The second cartridge portion may comprise a current collector holder and a current collector assembly. The current collector holder may comprise one or more piercing elements. The one or more piercing elements may be arranged to pierce or penetrate the seal of the second cartridge portion when the first and second cartridge portions are moved from the storage configuration to the use configuration.

When the first and second portions of the cartridge are moved from the storage configuration to the use configuration, one or more piercing elements of the susceptor holder may pierce the seal and allow the aerosol-forming substrate to flow from the first portion of the reservoir to the second portion of the reservoir.

The current-collecting unit may extend into the second portion of the reservoir. If the current-collecting unit contains a wick element, a portion of the wick element may extend into the second portion of the reservoir. Accordingly, when the cartridge is in storage configuration, the current-collecting unit is isolated from the aerosol-forming substrate, and when the cartridge is in use configuration, the current-collecting unit is supplied with aerosol-forming substrate from the second portion of the reservoir.

The seal may be any suitable type of seal to prevent fluid flow between the first portion of the tank and the second portion of the tank. For example, the seal may comprise a metal foil, a plastic foil, or an elastomeric seal.

The first and second parts of the cartridge may be movable relative to each other in any suitable manner. In some embodiments, the first and second parts of the cartridge may be slidable relative to each other. In some embodiments, the first and second parts of the cartridge may be rotatable relative to each other.

The aerosol-generating system may be a hand-held aerosol-generating system configured to allow the user to draw on a mouthpiece to draw the aerosol through an opening at the mouthpiece end. The aerosol-generating system may be sized similar to a traditional cigar or cigarette. The aerosol-generating system may have an overall length of approximately 30 mm to approximately 150 mm. The aerosol-generating system may have an outer diameter of approximately 5 mm to approximately 30 mm.

The aerosol-generating system may be configured to deliver nicotine or cannabinoids to the user. The aerosol-generating system may be an electric smoking device.

According to the present invention, a current-collecting unit is also provided for an electrically heated aerosol-generating system, comprising a housing forming a reservoir containing an aerosol-generating substrate, at least one induction coil, and a power source connected to at least one induction coil and configured to supply an oscillating current to at least one induction coil such that the induction coil generates an alternating magnetic field. The current-collecting unit may comprise a first current-collecting element configured to be heated by an alternating magnetic field. The current-collecting unit may comprise a second current-collecting element configured to be heated by an alternating magnetic field. The current-collecting unit may comprise a wick element that is in fluid communication with the reservoir of the aerosol-generating system. The first and second current-collecting elements are an integral part of the wick element or are attached to it. A space may be defined between the first and second current-collecting elements, the wick element occupies this space.

The following is a non-exhaustive list of non-limiting examples. Any one or more of the features of these examples may be combined with any one or more features of another example, embodiment, or aspect described herein.

EX1. An electrically heated aerosol generating system comprising:

at least one induction coil;

a power source connected to at least one induction coil and configured to supply alternating current to at least one induction coil to generate an alternating magnetic field;

a housing containing a reservoir with an aerosol-forming substrate; and

essentially a flat current-collecting unit, wherein the current-collecting unit is designed with the possibility of heating by an alternating magnetic field and contains a first current-collecting element, a second current-collecting element and a wick element communicating through a fluid medium with a reservoir, wherein the first and second current-collecting elements are an integral part of the wick element or are attached to it;

in this case, a space is defined between the first and second current-collecting elements, the wick element occupies the space, and the reservoir is located outside the space.

EX2. An electrically heated aerosol generating system according to EX1, wherein the first and second current collecting elements are permeable to the fluid medium.

EX3. An electrically heated aerosol generating system according to example EX1 or EX2, wherein the aerosol-forming substrate is a liquid.

EX4. An aerosol generating system according to any one of the examples EX1-EX3, wherein the wick element is arranged to transfer the aerosol-forming substrate from the liquid reservoir through the main surface of the current collecting element.

EX5. An electrically heated aerosol generating system according to example EX3 or EX4, wherein the current collecting unit or the heating region of the current collecting unit holds from 2 to 10 milliliters of a liquid aerosol-forming substrate.

EX6. An aerosol generating system according to any of the previous examples, wherein at least a portion of each of two opposing major surfaces of the susceptor assembly is in direct contact with air in an air flow passage in the system.

EX7. An electrically heated aerosol generating system according to any of the previous examples, wherein the first and second current collecting elements have a relative permeability of from 1 to 40,000, preferably from 500 to 40,000.

EX8. An electrically heated aerosol generating system according to any of the previous examples, wherein the alternating current has a frequency of from 100 kHz to 30 MHz, preferably from 500 kHz to 30 MHz.

EX9. An electrically heated aerosol generating system according to any of EX1-EX7, wherein the alternating current has a frequency of from 100 kHz to 1000 MHz.

EX10. An electrically heated aerosol generating system according to any of the preceding examples, wherein the thickness of each current-collecting element is of the same order of magnitude or less than the depth of the surface layer of the current-collecting element material at the operating frequency of the system.

EX11. An aerosol generating system according to any of the preceding examples, wherein each current-collecting element has a thickness of no more than two millimetres.

EX12. An electrically heated aerosol generating system according to any of the previous examples, wherein the first and second current collecting elements comprise electrically conductive threads.

EX13. An electrically heated aerosol generating system according to example EX12, wherein the first and second current collecting elements comprise a mesh, a flat spiral coil, fibers or fabric made of electrically conductive threads.

EX14. An electrically heated aerosol generating system according to example EX12 or EX13, wherein the electrically conductive threads have a diameter of 40 to 60 micrometers, preferably 45 to 55 micrometers, and even more preferably 50 micrometers.

EX15. An electrically heated aerosol generating system according to any of the examples EX12-EX14, wherein the mesh size of the conductive threads is from 60 to 150 micrometers, preferably from 50 to 70 micrometers, even more preferably from 60 to 65 micrometers and most preferably 63 micrometers.

EX16. An electrically heated aerosol generating system according to any of the previous examples, wherein the first and second current collecting elements comprise an electrically conductive material printed or otherwise applied to the wick element.

EX17. An electrically heated aerosol generating system according to example EX16, wherein the electrically conductive material of the first or second current collecting element is printed or otherwise applied to the wick element in the form of a film or a plurality of tracks.

EX18. An electrically heated aerosol generating system according to EX17, wherein the plurality of tracks of each of the current collecting elements are distributed over the surface of the wick element.

EX19. An electrically heated aerosol generating system according to example EX17 or EX18, wherein the plurality of tracks of each of the current collecting elements form a grid-like structure.

EX20. An electrically heated aerosol generating system according to any of the examples EX1-EX11, wherein the first and second current collecting elements comprise a perforated foil.

EX21. An electrically heated aerosol generating system according to EX20, wherein the perforations are uniformly distributed over the first and second current-collecting elements.

EX22. An electrically heated aerosol generating system according to any of the preceding examples, wherein the wick element comprises an electrically insulating material.

EX23. An electrically heated aerosol generating system according to any of the preceding examples, wherein the wick element comprises a non-metallic material.

EX24. An electrically heated aerosol generating system according to any of the previous examples, wherein the wick element comprises a hydrophilic material or an oleophilic material.

EX25. An electrically heated aerosol generating system according to any of the preceding examples, wherein the wick element comprises cotton, viscose, or fiberglass.

EX26. An electrically heated aerosol generating system according to any one of EX1-EX24, wherein the wick element comprises a porous ceramic material.

EX27. An electrically heated aerosol generating system according to any of the previous examples, wherein at least one induction coil comprises a first induction coil and a second induction coil.

EX28. An electrically heated aerosol generating system according to example EX27, wherein the first induction coil is located on a first side of the current collecting unit, and the second induction coil is located on a second side of the current collecting unit and extends parallel to the first plane.

EX30. An electrically heated aerosol generating system according to paragraph 28 or paragraph 29, wherein the current collecting unit is substantially equidistant from the first and second induction coils.

EX31. An aerosol generating system according to any of the examples EX27-EX30, wherein the system is designed such that the first and second induction coils create equal and opposite magnetic fields.

EX32. An aerosol generating system according to any of the examples EX28-EX31, wherein the system is designed such that the first and second induction coils provide a magnetic field on the current collecting unit that is perpendicular to the first plane. EX33. An aerosol generating system according to any of the examples EX27-EX32, wherein each of the flat induction coils is rectangular.

EX34. An aerosol generating system according to any of the examples EX27-EX33, wherein the first induction coil has the same number of turns as the second induction coil.

EX35. An aerosol generating system according to any of the examples EX27-EX34, wherein the first induction coil has the same size and shape as the second induction coil.

EX36. An aerosol generating system according to any of the examples EX27-EX35, wherein the first induction coil is substantially identical to the second induction coil.

EX37. An aerosol generating system according to any of the examples EX27-EX36, wherein the first induction coil has the same electrical resistance as the second induction coil.

EX38. An aerosol generating system according to any one of EX27-EX37, wherein the induction coils are electrically connected to form a single conductive path, and wherein the first induction coil is wound in the opposite direction to the second induction coil.

EX39. An aerosol generating system according to any of the examples EX27-EX38, wherein the first and second induction coils are provided with the same alternating electric current.

EX40. An aerosol generating system according to any of the examples EX27-EX3 9, wherein the first induction coil is wound in the same direction as the second induction coil, and wherein the control circuit is configured to supply a current to the first induction coil that is in antiphase with the current supplied to the second induction coil.

EX41. An aerosol generating system according to any of the examples EX27-EX40, comprising one or more flow concentrators configured to retain a magnetic field generated by induction coils.

EX42. An aerosol generating system according to any of the previous examples, further comprising a current collector holder, and wherein each of the current collectors comprises a heating region and at least one fastening region, wherein the heating region is a region of the current collector element configured to be heated to a temperature necessary for evaporating the liquid substrate forming the aerosol from the liquid reservoir upon penetration of a suitable alternating magnetic field therein, and wherein at least one fastening region of the current collector element is a region of the current collector element that is configured to be in contact with the current collector holder.

EX43. An aerosol generating system according to example EX42, wherein the heating region is capable of being heated to a substantially higher temperature than the fastening region in the presence of an alternating magnetic field.

EX44. An aerosol generating system according to example EX42 or EX43, wherein the heating region is located in the space directly between the first and second induction coils, and the fastening region may be located outside the space directly between the first and second induction coils.

EX45. An aerosol generating system according to any of the examples EX42-EX44, wherein the heating area of each of the current-collecting elements is located outside the liquid reservoir.

EX46. An electrically heated aerosol generating system according to any of the preceding examples, further comprising an air flow passage extending between the air inlet and the air outlet.

EX47. An electrically heated aerosol generating system according to EX46, wherein the air outlet is defined in the mouthpiece of the system.

EX48. An electrically heated aerosol generating system according to example EX46 or EX47, wherein the air flow in the air flow passage passes over the surface of the first current-collecting element and the surface of the second current-collecting element.

EX49. An electrically heated aerosol generating system according to any one of EX46-EX48, wherein the wick element is in fluid communication with the reservoir since the wick element extends into the reservoir.

EX50. An electrically heated aerosol generating system according to any of the preceding examples, wherein the housing comprises an inner wall and an outer wall such that the inner passage is defined by the inner wall.

EX51. An electrically heated aerosol generating system according to example EX50, wherein the internal passage is surrounded by a space defined between the internal wall and the external wall.

EX52. An electrically heated aerosol generating system according to EX51, wherein the space surrounding the internal passage is an annular space.

EX53. An electrically heated aerosol generating system according to example EX51 or EX52, wherein the air flow channel can be at least partially defined by an internal passage and the reservoir can be at least partially defined by a space surrounding the internal passage.

EX54. An electrically heated aerosol generating system according to example EX51 or EX52, wherein the reservoir is at least partially defined by an internal passage and the air flow passage is at least partially defined by an annular space.

EX55. An electrically heated aerosol generating system according to any of the previous examples, wherein the aerosol generating system comprises a current collecting unit holder on which the current collecting unit is mounted.

EX56. An electrically heated aerosol generating system according to example EX55, wherein the current collecting elements in the current collecting unit comprise at least one fastening region that contacts the holder.

EX57. An electrically heated aerosol generating system according to example EX55 or EX56, wherein the current collecting unit holder is tubular and has at least one side wall.

EX58. An electrically heated aerosol generating system according to example EX57, wherein the current collecting unit is mounted via at least one opening in the side wall.

EX59. An electrically heated aerosol generating system according to example EX57 or EX58, wherein the current collecting unit is mounted via at least two openings in the side wall.

EX60. An electrically heated aerosol generating system according to any of the examples EX55-EX59, wherein the current collecting unit holder is configured to withstand temperatures to which the current collecting unit is raised to heat the aerosol-forming substrate.

EX61. An electrically heated aerosol generating system according to any of EX55-EX60, wherein the current collecting member holder is formed from a liquid-impermeable material.

EX62. An electrically heated aerosol generating system according to any one of the examples EX55-EX61, wherein the current collector holder is formed from a moldable plastic material such as polypropylene (PP) or polyethylene terephthalate (PET).

EX63. An electrically heated aerosol generating system according to any of the examples EX57-EX62, wherein at least one side wall of the current collecting unit holder forms at least part of the inner wall of the housing.

EX64. An electrically heated aerosol generating system according to example EX63, wherein the housing comprises an inner wall and an outer wall such that the inner passage is defined by the inner wall, and wherein at least one side wall of the housing defines a portion of the inner passage.

EX65. An electrically heated aerosol generating system according to example EX64, wherein the space between the inner wall and the outer wall is at least partially defined between at least one side wall and the outer wall of the housing.

EX66. An electrically heated aerosol generating system according to EX65, wherein the current collector assembly extends into the internal channel of the current collector holder.

EX67. An electrically heated aerosol generating system according to any of EX55-EX66, wherein the holder is formed on the current collecting unit.

EX68. An electrically heated aerosol generating system according to example EX67, wherein the molded holder holds the first and second current collecting elements and the wick element together such that the elements are secured together.

EX69. An electrically heated aerosol generating system according to any of the preceding examples, wherein the current collecting unit is surrounded by a permeable electrically insulating coating.

EX70. An electrically heated aerosol generating system according to EX69, wherein the coating comprises a permeable ceramic material.

EX71. An electrically heated aerosol generating system according to any of the previous examples, wherein the current collecting unit further comprises a third current collecting element and a second wick element, wherein the second wick element is located between the first current collecting element and the third current collecting element or the second current collecting element and the third current collecting element.

EX72. The electrically heated aerosol generating system according to any of the previous examples further comprises a second current collecting unit that is substantially similar to the first current collecting unit.

EX73. An electrically heated aerosol generating system according to any of the previous examples, wherein the system further comprises an electrical circuit connected to at least one induction coil and to a power source.

EX74. An electrically heated aerosol generating system according to any of the previous examples, wherein the aerosol generating system comprises an aerosol generating device and a cartridge configured for use with the device comprising at least one induction coil, a power source and a device housing configured to engage at least a portion of the cartridge when the cartridge is used with the aerosol generating device.

EX75. An electrically heated aerosol generating system according to EX74, wherein the cartridge comprises a current collecting unit and a cartridge housing.

EX76. An electrically heated aerosol generating system according to example EX74 or EX75, wherein at least one induction coil is located around or near the current collecting unit when the cartridge is engaged with the aerosol generating device.

EX77. An electrically heated aerosol generating system according to any of the examples EX74-EX76, wherein the aerosol generating system comprises first and second induction coils, the first induction coil being located on a first side of the cartridge, and the second induction coil being located on a second side of the cartridge when the cartridge is engaged with the aerosol generating device.

EX78. An electrically heated aerosol generating system according to example EX77, wherein the portion of the cartridge containing the current collecting unit of the cartridge is located between the first and second induction coils when the cartridge is engaged with the aerosol generating device.

EX79. A cartridge for use in an electrically heated aerosol generating system; the electrically heated aerosol generating system comprises an aerosol generating device; the cartridge is adapted for use with the device, wherein the device comprises: a device housing adapted to engage at least a portion of the cartridge when the cartridge is used with the aerosol generating device; at least one induction coil; and a power source connected to the at least one induction coil and adapted to supply alternating current to the at least one induction coil such that the induction coil generates an alternating magnetic field within the cartridge; the cartridge comprises:

a cartridge housing defining a reservoir containing an aerosol-forming substrate; and

essentially a flat current-collecting unit, designed with the possibility of heating by an alternating magnetic field and containing a first current-collecting element, a second current-collecting element and a wick element communicating through a fluid medium with a reservoir, wherein the first and second current-collecting elements are a single unit with the wick element or are attached to it;

wherein a space is defined between the first and second current-collecting elements, the wick element occupies the space, and the reservoir is located outside the space, occupies the space, and the reservoir is located outside the space.

EX80. A cartridge according to example EX79, wherein the first and second current-collecting elements are permeable to the fluid medium.

EX81. A cartridge according to example EX79 or EX80, wherein the aerosol-forming substrate is a liquid.

EX82. A cartridge according to any of the examples EX79-EX81, wherein the wick element is arranged to transfer the aerosol-forming substrate from the liquid reservoir through the main surface of the current-collecting element.

EX83. A cartridge according to example EX81 or EX82, wherein the current-collecting unit or the heating area of the current-collecting unit holds from 2 to 10 milliliters of liquid substrate that forms an aerosol.

EX84. A cartridge according to any of the examples EX79-EX83, wherein at least a portion of each of the two opposing major surfaces of the current collecting unit is in direct contact with air in the air flow passage in the system.

EX85. A cartridge according to any of the examples EX79-EX84, wherein the first and second current-collecting elements have a relative permeability from 1 to 40,000, preferably from 500 to 40,000.

EX86. A cartridge according to any of the examples EX7 9-EX85, wherein the thickness of each current-collecting element is of the same order of magnitude or less than the depth of the surface layer of the current-collecting element material at the operating frequency of the system.

EX87. A cartridge according to any of the examples EX79-EX86, wherein the thickness of the current collector unit is no more than two millimeters.

EX88. A cartridge according to any of the examples EX79-EX87, wherein the first and second current-collecting elements comprise electrically conductive threads.

EX89. A cartridge according to example EX88, wherein the first and second conductive elements comprise a mesh, a flat spiral coil, fibers or fabric made of conductive threads.

EX90. A cartridge according to example EX88 or EX89, wherein the diameter of the conductive threads is from 40 to 60 micrometers, preferably from 45 to 55 micrometers and even more preferably 50 micrometers.

EX91. A cartridge according to any of the examples EX88-EX90, wherein the mesh size of the conductive threads is from 60 to 150 micrometers, preferably from 50 to 70 micrometers, even more preferably from 60 to 65 micrometers and most preferably 63 micrometers.

EX92. A cartridge according to any of the examples EX79-EX91, wherein the first and second current collecting elements comprise an electrically conductive material printed or otherwise applied to the wick element.

EX93. A cartridge according to example EX92, wherein the electrically conductive material of the first or second current-collecting element is printed or otherwise applied to the wick element in the form of a film or a plurality of tracks.

EX94. A cartridge according to example EX93, wherein the plurality of tracks of each of the current-collecting elements are distributed over the surface of the wick element.

EX95. A cartridge according to the example EX93 or EX94, wherein the plurality of tracks of each of the current-collecting elements form a grid-like structure.

EX96. A cartridge according to any of the examples EX79-EX91, wherein the first and second current collecting elements comprise a perforated foil.

EX97. A cartridge according to the example EX96, in which the perforations are evenly distributed over the first and second current-collecting elements.

EX98. A cartridge according to any of the examples EX79-EX97, wherein the wick element comprises an electrically insulating material.

EX99. A cartridge according to any of the examples EX79-EX98, wherein the wick element comprises a non-metallic material.

EX100. A cartridge according to any of the examples EX79-EX99, wherein the wick element comprises a hydrophilic material or an oleophilic material.

EX101. A cartridge according to any of the examples EX79-EX100, wherein the wick element comprises cotton or viscose.

EX102. A cartridge according to any of the examples EX79-EX101, wherein the wick element comprises a porous ceramic material.

Features described with respect to one example or embodiment may be applied to other examples and embodiments.

Below the examples will be further described with reference to figures, where:

Fig. 1a is a schematic illustration of an aerosol generating system according to one example of the present invention;

Fig. 1b is a schematic representation of the aerosol generating system of Fig. 1a, rotated 90 degrees relative to the central longitudinal axis of the aerosol generating system;

Fig. 2a-c show schematic images of the cartridge of the system according to Fig. 1a and 1b;

Fig. 3 is a perspective view of the current collecting unit and current collecting unit holder according to the present invention, separated from the rest of the aerosol generating system;

Fig. 4 shows a top view of the current collecting unit of Figs. 1 and 2, separated from the rest of the aerosol generating system;

Fig. 5 is an exploded perspective view of an embodiment of a current collecting unit according to the present invention;

Fig. 6a shows an image of the system of Fig. 1b with magnetic field lines shown for one phase of operation;

Fig. 6b shows an illustration of the system of Fig. 1b with magnetic field lines shown for the next phase of operation;

Fig. 7 is an exploded perspective view of another embodiment of a current collecting unit according to the present invention;

Fig. 8 is a perspective view of a further embodiment of a current collecting unit according to the present invention;

Fig. 9 is a perspective view of a current collecting unit comprising a coating according to the present invention;

Fig. 10a shows a perspective view of an embodiment of a current collecting unit according to the present invention.

an invention having a shape different from the current collecting unit of Fig. 4;

Fig. 10b shows a top view of the current collecting unit according to Fig. 10a;

Fig. 11a-d are top views of illustrative current-collecting elements according to the present invention;

Fig. 12a-i are top views of additional illustrative current-collecting elements according to the present invention;

Fig. 13A is a schematic illustration of an aerosol generating system according to another example of the present invention;

Fig. 13b is a schematic representation of a portion of the device of Fig. 13a, rotated 90 degrees relative to the central longitudinal axis of the aerosol generating system;

Fig. 13c shows an end view of the device according to Fig. 13b;

Fig. 14 is a schematic representation of a device consisting of coils and a current collector in one embodiment;

Fig. 15a is a schematic illustration of a cartridge for an aerosol generating system before use according to a further example of the present invention;

Fig. 15b is a schematic representation of the cartridge of Fig. 9a in a use configuration;

in Fig. 16a is a system comprising a cartridge according to Fig. 15b;

Fig. 16b shows the aerosol generating system of Fig. 16a, rotated 90 degrees relative to the central longitudinal axis of the aerosol generating system;

Fig. 17a is a sectional view of a flat current-collecting element according to another example of the present invention, wherein the sectional view is taken in a plane perpendicular to the plane of the current-collecting element; and

Fig. 17b shows a top view of the current collecting element according to Fig. 17a.

Fig. 1a is a schematic representation of an aerosol generating system according to one example of the present invention. Fig. 1b is a schematic representation of the aerosol generating system of Fig. 1a, rotated 90 degrees relative to the central longitudinal axis of the aerosol generating system. The system comprises a cartridge 10 and a device 60, which are connected together to form an aerosol generating system. The aerosol generating system is portable and has a size comparable to the size of a traditional cigar or cigarette.

The cartridge 10 comprises a current-collecting (suspender) unit 12 mounted in a current-collecting (suspender) holder 14. Fig. 2a-c show the cartridge 10 separately from the aerosol-generating system. Fig. 3 shows a perspective view of the current-collecting (suspender) unit 12 and the holder 14 separately from the rest of the aerosol-generating system. Fig. 4 and 5 show the design of the current-collecting (suspender) unit 12 more clearly. Fig. 4 shows a schematic cross-sectional view of the current-collecting (suspender) unit 12. Fig. 5 shows a schematic exploded view of the current-collecting (suspender) unit 12.

The current-collecting (suspender) unit 12 is flat and thin, and its thickness is significantly smaller than its length and width. The current-collecting (suspender) unit 12 comprises three elements: a first current-collecting (suspender) element 16, a second current-collecting (suspender) element 18, and a wick element 20 located between the first and second current-collecting (suspender) elements 16, 18. Each of the first current-collecting (suspender) element 16, the second current-collecting (suspender) element 18, and the wick element 20 has the same length and width dimensions. The first and second current-collecting (suspender) elements 16, 18 are substantially identical and comprise a sintered mesh formed by ferritic stainless steel threads and austenitic stainless steel threads, as described in more detail below. The wick element 20 comprises a porous body of viscose threads. The wick element 20 is configured to supply liquid from the outer exposed surfaces of the wick element 20 to the first and second current-collecting (suspender) elements 16, 18.

Each of the first and second current-collecting (susceptor) elements 16, 18 comprises a mesh having threads extending in a first direction and threads extending in a second direction, substantially perpendicular to the first direction. The conductive threads consist of threads made of AISI 430 stainless steel. The mesh cell size is 63 micrometers, and the diameter of the conductive threads is 50 micrometers.

Each of the first and second current-receiving (suspender) elements 16, 18 comprises a pair of fastening regions 22 and a heating region 24. The heating region 24 is a substantially rectangular region located in the center of the current-receiving (suspender) elements 16, 18. The pair of fastening regions 22 also are substantially rectangular regions located on the periphery of the heating region 24, on opposite sides of the heating region 24. The heating region 24 is configured to be heated by penetration of an alternating magnetic field to evaporate the substrate that forms the aerosol. The pair of fastening regions 22 are configured to contact the current-receiver (suspender) holder 14, so that the current-receiver (suspender) holder 14 can hold the current-receiving (suspender) assembly 12 in place in the cartridge 10.

The pair of fastening regions 22 comprises threads of AISI 316 stainless steel in addition to threads of AISI 430 stainless steel extending in the first direction and austenitic stainless steel extending in the second direction. Accordingly, the heating region 24 consists of a magnetic material, and the pair of fastening regions 22 consists partly of a magnetic material and partly of a non-magnetic material. The weight percentage of AISI 430 stainless steel in the heating region 24 is greater than the weight percentage of AISI 430 in each of the pair of fastening regions 22.

Accordingly, heating region 24 consists of a magnetic material, and the pair of fastening regions 22 consists partially of magnetic material and partially of non-magnetic material. The weight percentage of AISI 430 stainless steel in heating region 24 is greater than the weight percentage of AISI 430 stainless steel in each of the pair of fastening regions 22. This helps reduce the heating of fastening regions 22 when the alternating magnetic field penetrates the current-collecting (suspender) elements. This configuration also helps reduce heat transfer from current-collecting (suspender) assembly 12 to current-collecting (suspender) holder 14.

It should be understood that in other embodiments, the heating region 24 and the pair of fastening regions 22 may be made of other combinations of magnetic and non-magnetic materials. For example, in some embodiments, the heating region 24 comprises threads of AISI 430 stainless steel, a ferritic stainless steel, extending in a first direction, and threads of AISI 316 stainless steel, an austenitic stainless steel, extending in second directions. In these embodiments, the pair of fastening regions 22 may comprise threads of AISI 316 stainless steel extending in both the first and second directions. Accordingly, in these embodiments, the heating region 24 is partially composed of a magnetic material and partially of a non-magnetic material, and the pair of fastening regions 22 is composed of a non-magnetic material.

The current collector (suspender) holder 14 comprises a tubular body made of a moldable plastic material, such as polypropylene. The tubular body of the current collector (suspender) holder 14 comprises a side wall defining an internal passage 2 6 with open ends. A pair of openings 28 extend through the side wall on opposite sides of the tubular current collector (suspender) holder 14. The openings 28 are located centrally along the length of the current collector holder 14.

The current-collecting (susceptor) unit 12 is located inside the internal passage 26 of the tubular current-collecting holder 14 and extends in a plane parallel to the central longitudinal axis of the current-collecting holder 14. The heating region 24 of the first and second current-collecting elements 16, 18 is completely located inside the internal passage 26 of the current-collecting holder 14, and each of the fastening regions 22 passes through one of the openings 28 in the side wall of the current-collecting holder 14. The openings 28 in the side wall of the current-collecting holder 14 have a size capable of accommodating the current-collecting unit 12 with a friction fit, so that the current-collecting unit is secured in the current-collecting holder 14. The friction fit between the current collecting unit 12 and the current collecting holder 14 causes the fastening areas 22 to directly contact the current collecting holder 14 in the openings 28. The current collecting unit 12 and the current collecting holder 14 are fastened together in such a way that movement of the current collecting holder 14 also causes movement of the current collecting unit 12.

It should be understood that the current collector assembly 12 and the current collector holder 14 may be fastened together by other means. For example, in some embodiments, the current collector assembly 12 is fastened to the current collector holder 14 using adhesive in the fastening areas 22 of the current collector assembly 12, such that the fastening areas 22 indirectly contact the current collector holder 14.

The current collector holder 14 comprises a base 30 that partially closes one end of the internal passage 26. The base 30 comprises a plurality of air inlet openings 32 that allow air to be drawn into the internal passage 26 through the partially closed end.

The current collector holder 14 further comprises a pair of piercing elements 34 extending from the outer surface of the side wall to the open end of the current collector holder 14 opposite the end partially closed by the base 30. The openings 28 in the side wall of the current collector holder 14 are arranged between the piercing elements 34 along the circumference of the side wall in such a way that the piercing elements 34 are offset from the openings 28 along the circumference of the tubular current collector side wall by approximately 90 degrees. Each of the piercing elements 3 4 comprises a pin facing in the direction of the open end of the current collector holder 14.

Cartridge 10 further comprises an outer housing 36 made of a moldable plastic material, such as polypropylene. Outer housing 36 typically forms a hollow cylinder defining an internal space in which current collector assembly 12 and current collector holder 14 are housed.

The outer housing 36 forms the first part of the cartridge 10, and the current collector unit 12 and the current collector holder 14 form the second part of the cartridge 10. The second part of the cartridge can be configured to slide relative to the first part of the cartridge between a storage configuration, as shown in Fig. 2a and 2b, and a use configuration, as shown in Fig. 2c.

The cartridge 10 has a mouthpiece end and a connecting end opposite the mouthpiece end. The outer housing 36 forms an opening 38 at the mouthpiece end of the cartridge 10. The connecting end is configured to connect the cartridge 10 to an aerosol-generating device, as described in detail below. The current-collecting unit 12 and the current-collecting holder 14 are located closer to the connecting end of the cartridge 10. The outer width of the outer housing 36 is greater at the mouthpiece end of the cartridge 10 than at the connecting end connected to the projection 37. This allows the connecting end of the cartridge to be placed in the cavity of the aerosol-generating device, while the projection 37 fixes the cartridge in the correct position in the device. This also allows the mouthpiece end of the cartridge 10 to remain outside the aerosol-generating device, while the mouthpiece end corresponds to the external shape of the aerosol-generating device.

A liquid reservoir 40 is formed in a cartridge for holding a liquid substrate 42 that forms an aerosol. The liquid reservoir 40 is divided into two parts: a first part 44 and a second part 46. The first part 44 of the liquid reservoir 40 is located closer to the mouthpiece end of the outer housing 36 and contains an annular space formed by the outer housing 36. The annular space has an internal passage 4 8 that extends between the opening 38 at the mouthpiece end of the mouth and the open end of the internal passage 26 of the current collector holder 14. The second part 4 6 of the liquid reservoir 40 is located closer to the connecting end of the outer housing 36 and contains an annular space formed between the inner surface of the outer housing 36 and the outer surface of the current collector holder 14. The base 20 of the tubular current collector holder 14 is provided with an annular ribbed elastomer seal 50, which passes between the outer surface of the tubular current collector 14 and the inner surface of the outer housing 36. The seal 50 provides a liquid-tight seal between the current collector holder 14 and the outer housing 36, ensuring that the second part 46 of the liquid reservoir 40 is capable of holding the substrate 42 that forms the liquid aerosol.

The first and second portions 44, 46 of the liquid reservoir 40 are fluidly isolated from each other by means of an aluminum foil seal 52, which is pierced by the piercing elements 34 of the current collector holder, which allows the liquid substrate 42 forming the aerosol to pass between the first and second portions 44, 46 of the liquid reservoir, which is described in more detail below.

An air passage through the cartridge 10 is formed by the internal passage 26 of the current collector holder 14 and the internal passage 4 8 through the first part 44 of the liquid reservoir 40. The air passage extends from the air inlet openings 32 in the base 30 of the current collector holder 14 through the internal passage 26 of the current collector holder 14 and through the internal passage 48 of the first part 44 of the liquid reservoir 40 to the opening 38 at the mouthpiece end. The air passage allows air to be drawn through the cartridge 10 from the connecting end to the mouthpiece end.

In the storage configuration, as shown in Fig. 2a and 2b, the base 30 of the current collector holder 14 extends beyond the outer housing 36, and the piercing elements 34 of the current collector holder 14 are at a distance from the seal 52 in the direction of the connecting end of the cartridge 10. In this configuration, the liquid substrate 42 that forms an aerosol is held in the first part 44 of the liquid reservoir 40 and is isolated from the second part 46 of the liquid reservoir 40 by the seal 52. Accordingly, in the storage configuration, the current collector assembly 12 is isolated from the aerosol-forming substrate 42. Advantageously, sealing the liquid substrate 42 that forms an aerosol in the first part 44 of the liquid reservoir 40 can completely prevent the aerosol-forming substrate 42 from leaking from the cartridge 10 when the cartridge is in the storage configuration.

In the configuration of use as shown in Fig. 2c, the current collector holder 14 and the current collector unit 12 are inserted into the outer housing 36 in the direction toward the mouthpiece end. As the current collector holder 14 moves toward the mouthpiece end of the outer housing 36, the seal 50 at the base 30 of the current collector holder 14 slides along the inner surface of the outer housing 36, maintaining a liquid-tight seal between the inner surface of the outer housing 36 and the outer surface of the body of the tubular current collector holder, while the base of the current collector holder 14 is placed in the outer housing. As the piercing elements 34 of the current collector holder 14 move toward the mouthpiece end, the piercing elements 34 contact and pierce the seal 52, providing fluid communication between the first part 44 of the liquid reservoir 40 and the second part 46 of the liquid reservoir 40. The liquid substrate 42 forming the aerosol in the first part 44 of the liquid reservoir 40 is released into the second part 46 of the liquid reservoir 40, and the current collecting unit 12 is open to the liquid substrate 42 forming the aerosol.

In the storage configuration of the fastening region 22 of the first and second current-receiving elements 16, 18 and the corresponding parts of the wick element 20, which extend into the second part 46 of the liquid reservoir 40, are capable of drawing the liquid substrate 42, which forms the aerosol, from the second part 46 of the liquid reservoir 40 into the heating regions 24 of the first and second current-receiving elements 16, 18. As a result, in the use configuration, the cartridge 10 is ready for use for generating the aerosol by heating the aerosol-forming substrate 42. Although it is the wick element 2 0 that transports the aerosol-forming substrate from the reservoir to the first and second current-receiving elements by capillary action, the electrically conductive threads also cause capillary action in the spaces between the mesh threads to wet the first and second current-receiving elements 16, 18. Such wetting increases the contact area between the electrically conductive threads of the current-receiving element and the aerosol-forming substrate.

The aerosol generating device 60 comprises a generally cylindrical housing 62 comprising a connecting end and a distal end opposite the connecting end. A cavity 64 for receiving the connecting end of the cartridge is located at the connecting end of the device 60, and an air inlet 65 is provided in the outer housing 62 at the base of the cavity 64 to ensure that ambient air is drawn into the cavity 64 at the base.

The device 60 further comprises an induction heating device located in the housing 62. The induction heating device comprises a pair of induction coils 66, 68, a control circuit 70 and a power source 72. The power source 72 comprises a rechargeable nickel-cadmium battery that is recharged through an electrical connector (not shown) at the far end of the device. The control circuit 70 is connected to the power source 72, as well as to the first and second induction coils 66, 68, such that the control circuit 70 controls the supply of power to the induction coils 66, 68. The control circuit 70 is configured to supply alternating current to the first and second induction coils 66, 68.

A pair of induction coils includes a first induction coil 66 and a second induction coil 68. The first induction coil 66 is located on the first side of the cavity 64, and the second induction coil 68 is located on the second side of the cavity 64, opposite the first induction coil 66. Each of the induction coils 66, 68 is substantially identical and contains a flat coil with a rectangular cross-section, made of a wire with a rectangular cross-section. Each of the induction coils 66, 68 extends substantially in a plane, wherein the first coil 66 extends in the first plane, and the second coil 68 extends in the second plane. The first and second planes are substantially parallel to each other and extend substantially parallel to the central longitudinal axis of the cavity 64 at the connecting end of the device 60. When the cartridge 10 is placed in the cavity 64, the current collecting unit 12 is located between the first and second induction coils 66, 68, and the plane of the current collecting unit 12 is located substantially parallel to the first and second planes.

Flux concentrators 6 and 9 are provided around each of the induction coils to contain and concentrate the magnetic field within the cavity. Flux concentrators 6 and 9 can be made of a magnetic material, such as iron.

Each of the first and second induction coils 66, 68 is designed in such a way that when alternating current is supplied to the induction coils 66, 68, the induction coil generates an alternating magnetic field in the cavity 64. The alternating magnetic field generated by each of the induction coils 66, 68 is directed substantially perpendicular to the plane of the current-receiving unit 12 and the current-receiving elements 16, 18.

The induction heating device is also designed in such a way that the second induction coil 68 generates an alternating magnetic field in the cavity 64, which is equal to and opposite to the alternating magnetic field generated in the cavity 64 by the first induction coil 66. In this embodiment, the first and second induction coils 66, 68 are connected together in series and are substantially identical, but wound in opposite directions. In this configuration, the first and second induction coils 66, 68 generate alternating magnetic fields in the cavity 64 with substantially the same magnitudes, but in substantially opposite directions.

Fig. 6a and 6b show the system of Fig. 1b, but with magnetic field lines shown for the magnetic fields generated by the induction coils. Fig. 6a shows the magnetic field during the first half of the alternating current cycle. Fig. 6b shows the magnetic field during the second half of the alternating current cycle with the magnetic field in the opposite direction. It can be seen that during both halves of the cycle, the magnetic field on opposite sides of the current collector assembly 12 is equal and opposite in direction. This ensures a balance of forces on the current collector assembly. Equal and opposite magnetic fields can be achieved by winding the first and second induction coils in opposite directions and providing them with the same current. Equal and opposite magnetic fields can also be achieved by providing the second induction coil with an alternating current that is directly out of phase with the current supplied to the first induction coil.

During operation, when the user takes a puff through the opening 38 at the mouthpiece end of the cartridge 10, ambient air is drawn into the base of the cavity 64 through the air inlet 65 and into the cartridge 10 through the air inlet openings 32 in the base 30 of the cartridge 10, as shown by the arrows in Fig. 1b. The ambient air passes through the cartridge 10 from the base 30 to the opening 38 at the mouthpiece end through the air passage and over the current-collecting unit 12.

The control circuit 70 controls the supply of electric power from the power source 72 to the first and second induction coils 66, 68 when the system is activated. The control circuit 72 may comprise an air flow sensor (not shown), and the control circuit 72 may supply electric power to the induction coils 66, 68 when the air flow sensor detects puffs taken by the user from the cartridge 10. This type of arrangement of control elements is traditional in aerosol-generating systems such as inhalers and electronic cigarettes.

When the system is activated, an alternating current is established in each of the induction coils 66, 68, which generates an alternating magnetic field in the cavity 64, penetrating into the current-receiving unit 12, causing heating of the heating areas 24 of the first and second current-receiving elements 16, 18.

An alternating magnetic field passes through the current-collecting unit, inducing eddy currents in the first and second current-collecting elements. The first and second current-collecting elements 16, 18 heat up, reaching a temperature sufficient to evaporate the aerosol-forming substrate. The evaporating aerosol-forming substrate can exit the wick element 20 through the mesh of the current-collecting elements 16, 18. The current-collecting unit is configured to retain only a small volume of liquid aerosol-forming substrate, sufficient for a single user puff. This is advantageous because it allows for rapid evaporation of a small volume of liquid with minimal heat loss to other system components or to the liquid aerosol-forming substrate, which does not evaporate.

Furthermore, the aerosol-forming substrate primarily evaporates on the outer surfaces of the wick element 20, closest to the first and second current-collecting elements 16, 18. Since there are two current-collecting elements 16, 18, the wick element 20 is heated from both sides. Since the generated vapor can primarily be generated at the interface between the current-collecting elements and the wick element, it does not need to pass through the body of the wick element to exit the wick element, which would otherwise lead to cooling and possible condensation of the vapor. Instead, the vapor passes through the permeable current-collecting elements 16, 18 directly into the airflow passage.

Although it is the wick element 20 that transports the aerosol-forming substrate from the reservoir to the first and second current-receiving elements by capillary action, the conductive threads also cause capillary action in the spaces between the mesh threads to wet the first and second current-receiving elements 16, 18. Such wetting increases the contact area between the conductive threads of the current-receiving element and the aerosol-forming substrate.

Fig. 7 shows an exploded perspective view of another embodiment of the current collecting unit 112 according to the present invention. In this embodiment, the first and second current collecting elements 116, 118 consist of a perforated foil. The perforated foil is made of AISI 430 stainless steel. During operation, the evaporating substrate, which forms an aerosol, exits the wick element through the perforations 120 of the perforated foil. The wick element 20 consists of viscose. The perforations 120 in Fig. 7 are not shown to scale.

Fig. 8 shows a perspective view of an additional embodiment of the current collecting unit 212 according to the present invention. The first and second current collecting elements consist of an electrically conductive material applied directly to the wick element 520. Only the first current collecting element 216 is visible in Fig. 6. The second current collecting element is located on the underside of the wick element 220, which is not visible.

The electrically conductive material is applied in such a way that it forms multiple tracks distributed across the surface of the wick element 220. These tracks form a mesh structure. During operation, the evaporating substrate, which forms the aerosol, can predominantly exit the wick element 220 through the gaps 222 between the tracks. In this embodiment, the wick element 220 is comprised of a porous ceramic material. Such a porous ceramic material is a suitable substrate for manufacturing processes involving the deposition of electrically conductive material.

Fig. 9 is a perspective view of the current collecting unit 312 containing the ceramic coating 302. The ceramic material is a permeable ceramic material that allows the evaporating substrate to escape, forming an aerosol. The first and second current collecting elements and the wick element are represented by line 304 in Fig. 9. Fig. 9 is not drawn to scale.

The 302 coating increases the strength and stability of the current collector assembly. Furthermore, when the current collector assembly contains a coating, the components of the current collector element can be held together by the coating.

In Fig. 10a and 10b, a current collecting unit 412 is shown, the shape of which differs from the shape shown previously. In Fig. 10a and 10b, the current collecting unit has the shape of a cross. In Fig. 10a, a perspective view of the current collecting unit 412 is shown, and in Fig. 10b, a top view of the current collecting unit 412 is shown. Each of the first current collecting element 416, the second current collecting element 418, and the wick element 420 generally has the shape of a cross, and each element has the same dimensions in length and width.

Each of the pair of fastening regions 22 of the current-receiving elements 416, 418 has a smaller surface area than the heating region 24. The length 1 _m of each of the fastening regions 22 is less than the length l _h of the heating region 24, and the width w _m of each of the fastening regions 22 is less than the width w _h of the heating region 24. In this embodiment, the heating region 24 has a length l _h of approximately 6.50 millimeters and a width w _h of approximately 3.50 millimeters, and each of the fastening regions 22 has a length l _m of approximately 2.50 millimeters and a width w _m of approximately 1.15 millimeters. Thus, each of the first and second current-receiving elements 16, 18 has a total maximum length of approximately 6.50 millimeters and a total maximum width of approximately 5.80 millimeters.

Providing the first and second current-collecting elements 416, 418 with fastening regions 22 having a reduced cross-section compared to the heating region 24 and at least partially including fastening regions 22 made of a non-magnetic material helps reduce the heating of the fastening regions 22 when an alternating magnetic field penetrates the current-collecting elements. Such a configuration also helps reduce heat transfer from the current-collecting assembly 412 to the current-collecting holder 14.

Fig. 11a-11e show various other shapes of current collecting elements in accordance with various embodiments of the present invention.

Fig. 11a shows a current-collecting element having two rectangular fastening regions 22 located on one side of a rectangular heating region 24. Each fastening region 22 is substantially identical and has a width and length that are substantially shorter than the width and length of the heating region 24. The fastening regions 22 are located at opposite ends of the heating region 24, so that the current-collecting element typically has a "C" shape.

Fig. 11b shows a current-collecting element having two rectangular fastening regions 22 located on opposite sides of a rectangular heating region 24. Each fastening region 22 is substantially identical and has a width and length that are substantially shorter than the width and length of the heating region 24. The fastening regions 22 are located at the same end of the heating region 24, so that the current-collecting element typically has the shape of the letter "T."

Fig. 11c shows a current-collecting element having two rectangular fastening regions 22 located on opposite sides of a rectangular heating region 24. Each fastening region 22 is substantially identical and has a width and length that are substantially shorter than the width and length of the heating region 24. The fastening regions 22 are located at different locations along the length of the heating region 24 at a distance from the ends of the heating region 24.

Fig. 11d shows a current-collecting element having two rectangular fastening regions 22 located on opposite sides of a rectangular heating region 24. Each fastening region 22 is substantially identical and has a width and length that are substantially shorter than the width and length of the heating region 24. The fastening regions 22 are located at opposite ends of the heating region 24, so that the current-collecting element typically has the shape of the letter "S" or "Z."

Not shown in Fig. is a current-collecting element having one rectangular fastening region 22 located on one side of the heating region 24. The fastening region 22 has a width and a length that are significantly shorter than the width and length of the heating region 24. The fastening region 22 is located in a central position along the length of the heating region 24.

Fig. 12a-12i show further alternative shapes of current collecting elements in accordance with various embodiments of the present invention.

Fig. 12a-12c show current-receiving elements having substantially rectangular heating regions 24 and fastening regions 22, wherein each fastening region 22 of each current-receiving element is substantially identical and has a width and length that are substantially shorter than the width and length of the heating region 24.

Fig. 12a shows a current-receiving element having two pairs of fastening regions 22 located at opposite ends of a heating region 24. Each pair of fastening regions includes one fastening region 22 located on one side of the heating region 24 and one fastening region 22 located on the opposite side of the heating region 24, so that the current-receiving element typically has the shape of the letter "H".

Fig. 12b shows a current-receiving element having a pair of fastening regions 22 located on opposite sides of a heating region 24. The fastening regions 22 are located in the same central position along the length of the heating region 24, so that the current-receiving element generally has the shape of a cross.

Fig. 12c shows a current-receiving element having two pairs of fastening regions 22 located in different positions along the length of the heating region 24, at a distance from the ends of the heating region 24 and at a distance from another pair of fastening regions 22. Each pair of fastening regions 22 includes one fastening region 22 located on one side of the heating region 24 and one fastening region 22 located on the opposite side of the heating region 24, at the same place along the length of the heating region 24.

Fig. 12d-f show current collecting elements that are essentially similar to the current collecting elements shown in Fig. 12a-c, wherein one or more edges of the fastening regions 22 or the heating region 24 are located at an angle, so that one or more of the fastening regions 22 and the heating region 24 are not rectangular.

Fig. 12d shows a current collecting element substantially similar to the current collecting element of Fig. 12a, with the inner edges of the fastening regions 22 converging toward a central position along the length of the heating region 24, since the fastening regions 22 extend from the heating region 24.

Fig. 12e shows a current-collecting element that is essentially similar to the current-collecting element of Fig. 12b, with the edges of the fastening regions 22 diverging in the direction of the length of the heating region 24, since the fastening regions 22 extend from the heating region 24.

Fig. 12f shows a current-collecting element that is essentially similar to the current-collecting element of Fig. 12c, with the edges of the fastening regions 22 diverging in the direction of the length of the heating region 24, since the fastening regions 22 extend from the heating region 24.

Fig. 12g-i show current collecting elements that are essentially similar to the current collecting elements shown in Fig. 12a-c, wherein one or more edges of the fastening regions 22 or the heating region 24 are curved so that one or more of the fastening regions 22 and the heating region 24 are not rectangular.

Fig. 12d shows a current collecting element that is essentially similar to the current collecting element of Fig. 5a, with the inner edges of the fastening regions 22 curved inward to form concave inner edges of the fastening regions 22.

Fig. 12h shows a current collecting element essentially similar to the current collecting element of Fig. 5b, with the edges of the fastening regions 22 curved outward to form convex fastening regions 22.

Fig. 12i shows a current collecting element substantially similar to the current collecting element of Fig. 12c, with the edges of the fastening regions 22 curved outward to form convex fastening regions 22.

Fig. 13a, 13b, 13c show another embodiment of an aerosol generating system. The system also comprises a cartridge 10 and a device 80. The cartridge 10 is identical to the cartridge shown in Fig. 2a, 2b, and 2c and is shown in a configuration for use. However, in this embodiment, the device is designed such that the induction coils are located inside the cartridge being used.

The aerosol-generating device 80 comprises a generally cylindrical body 82 comprising a connecting end and a distal end opposite the connecting end. A cavity 81 for receiving the connecting end of the cartridge is located at the connecting end of the device 80, and an air inlet 85 is provided in the outer body 82 at the base of the cavity 81 to draw ambient air into the cavity at the base.

The device 80 further comprises an induction heating device housed in a housing 82. The induction heating device comprises a pair of induction coils 86, 88, a control circuit 83 and a power source 84. The power source 84 comprises a rechargeable nickel-cadmium battery that is recharged through an electrical connector (not shown) at the far end of the device. The control circuit 83 is connected to the power source 84, as well as to the first and second induction coils 86, 88, such that the control circuit 83 controls the supply of power to the induction coils 86, 88. The control circuit 83 is configured to supply alternating current to the first and second induction coils 86, 88.

A pair of induction coils includes a first induction coil 86 and a second induction coil 88. The first induction coil 86 and the second induction coil 88 extend into the cavity 81 and are held in the coil housings 8 9. The first induction coil 86 is located on one side of the current-collecting unit 12 when the cartridge is connected to the device, and the second induction coil 88 is located on the opposite side of the current-collecting unit with respect to the first induction coil 86. Each of the induction coils 86, 88 is substantially identical and contains a flat coil with a rectangular cross-section, made of a wire with a rectangular cross-section. Fig. 13b, which shows the device rotated by 90 degrees relative to Fig. 13a, more clearly illustrates the rectangular shape of the second induction coil 88. Each of the induction coils 86, 88 extends substantially in a plane, wherein the first coil 86 extends in a first plane, and the second coil 88 extends in a second plane. The first and second planes are substantially parallel to each other and extend substantially parallel to the central longitudinal axis of the cavity 81 at the connecting end of the device 80. When the cartridge 10 is placed in the cavity 81, the current collecting unit 12 is located between the first and second induction coils 86, 88, and the plane of the current collecting unit 12 is located substantially parallel to the first and second planes. In Fig. 13c, an end view of the device is shown, showing the position of the coil housings 89 in the cavity 81. The device and the cartridge housing are provided with a locking mechanism to ensure that the cartridge can be placed in the cavity 81 only in the desired orientation, ensuring that the current collecting unit will be located between the induction coils.

As in the embodiment of Fig. 1, each of the first and second induction coils 86, 88 is designed in such a way that when alternating current is supplied to the induction coils 86, 88, the induction coil generates an alternating magnetic field in the cavity 81. The alternating magnetic field generated by each of the induction coils 86, 88 is directed substantially perpendicular to the plane of the current-receiving unit 12 and the current-receiving elements.

The induction heating device is also designed in such a way that the second induction coil 88 generates an alternating magnetic field in the cavity 81, which is equal to and opposite to the alternating magnetic field generated in the cavity by the first induction coil 86. In this embodiment, the first and second induction coils 86, 88 are connected together in series and are substantially identical, but wound in opposite directions, as shown schematically in Fig. 14. In this configuration, the first and second induction coils 86, 88 generate alternating magnetic fields on any of the sides of the current collecting unit with substantially the same magnitudes, but in substantially opposite directions.

Fig. 14 shows a schematic representation of the arrangement of the coils according to Fig. 13a, 13b and 13c. It can be seen that the first and second induction coils 86, 88 are connected in series, but are wound in a direction opposite to each other. Thus, when an alternating current is supplied to the induction coils, they generate alternating magnetic fields in a direction opposite to each other. One main surface of the current collector assembly is acted upon by the magnetic field generated by the first induction coil 86, and the opposite main surface of the current collector assembly is acted upon by the magnetic field generated by the second induction coil 86. The current collector assembly and, in particular, the current collector elements are located at a substantially equal distance between the first and second induction coils, and thus such an arrangement means that the forces generated by the magnetic fields on the current collector element or elements, such as the Lorentz force, are balanced. This reduces deformation and movement of the current-collecting elements compared to a design using only a single induction coil. Furthermore, if there is any displacement of the current-collecting unit, this arrangement will tend to move the current-collecting unit to a central position, equidistant from the first and second induction coils.

Fig. 15a and 15b show schematic illustrations of a cartridge 10 for an aerosol generating device in accordance with another embodiment of the present invention. The cartridge 10 shown in Fig. 15a is substantially similar to the cartridge 10 shown in Fig. 2, and like features are designated by like reference numerals.

The cartridge 10 comprises two current collecting units 12 mounted in a current collecting holder 14. Each current collecting unit 12 is flat and thin and has the shape of the letter "C". Each current collecting unit 12 has the same three-element configuration as the current collecting unit 12 shown in Figs. 3a-3c, with a wick element located between the first and second current collecting elements (not shown). Each current collecting element has a rectangular heating region and two fastening regions located on one side of the heating region at opposite ends of the heating region, as shown in Fig. 15a.

The current collector holder 14 comprises a tubular body having a side wall that forms an internal passage 26 with open ends. Two pairs of openings 28 extend through the side wall, wherein each pair of openings 28 has one opening located on one side of the current collector holder 14 and the other opening located on the opposite side of the current collector holder 14.

In this embodiment, each of the two current collector assemblies 12 is located substantially outside the internal passage 26 of the tubular current collector holder 14 and extends in a plane parallel to the central longitudinal axis of the current collector holder 14. The heating region of each current collector element is located entirely outside the internal passage 26, and each of the fastening regions passes through one of the openings 28 in the side wall of the current collector holder.

The current collector holder comprises a base 30 that partially covers one end of the internal passage 26. In this embodiment, the base 30 forms a liquid-tight seal with the internal passage 26 such that the internal passage is configured to retain liquid. The base 30 comprises a plurality of air inlet openings 32; however, the air inlet openings 32 are located outside of the internal passage 26.

The current collector holder 14 additionally comprises a pair of piercing elements 34 extending from the inner surface of the side wall into the inner passage 26 in the direction of the central longitudinal axis of the current collector holder 14.

The cartridge 10 further comprises an outer housing 36, which typically forms a hollow cylinder defining an internal space in which the current collecting unit 12 and the current collecting holder 14 are housed. The outer housing 36 forms the first part of the cartridge 10, and the current collecting unit 12 and the current collecting holder 14 form the second part of the cartridge 10. The second part of the cartridge may be configured to slide relative to the first part of the cartridge between a storage configuration, as shown in Fig. 15a, and a use configuration, as shown in Fig. 15b.

Cartridge 10 has a mouthpiece end defining an opening 38 at the mouthpiece end and a connecting end configured to connect cartridge 10 to an aerosol-generating device. Current collector assembly 12 and current collector holder 14 are located closer to the connecting end of cartridge 10. The outer width of outer housing 36 is greater at the mouthpiece end of cartridge 10 than at the connecting end connected to projection 37.

A liquid reservoir 40 is formed in a cartridge for holding a liquid substrate 42 that forms an aerosol. The liquid reservoir 40 is divided into two parts: a first part 4 4 and a second part 46. The first part 44 of the liquid reservoir 40 is located closer to the mouthpiece end of the outer housing 36 and contains a cylindrical space formed by the inner wall of the outer housing 36. The second part 46 of the liquid reservoir 40 is located closer to the connecting end of the outer housing 36 and contains a cylindrical space formed by the internal passage 26 of the holder 14 of the current collector.

The first and second parts 44, 46 of the liquid reservoir 40 are fluidly isolated from each other by means of a seal 52 made of aluminum foil, which is pierced by piercing elements 34 of the current collector holder, which allows the liquid substrate 42 forming the aerosol to pass between the first and second parts 44, 46 of the liquid reservoir.

The first passage 48 is formed between the outer surface of the inner wall forming the first part 44 of the reservoir 40 for liquid, and the inner surface of the outer wall of the outer housing 36. The first passage 48 extends between the opening 38 at the mouthpiece end and the current collector holder 14. The second passage 49 is formed between the inner surface of the outer wall of the outer housing 36 and the outer surface of the current collector holder 14. The base 30 of the tubular current collector holder 14 is provided with an annular ribbed elastomer seal 50, which extends between the outer surface of the tubular current collector 14 and the inner surface of the outer wall of the outer housing 36. The seal 50 provides an airtight seal between the current collector holder 14 and the outer housing 36.

An air passage through the cartridge 10 is formed by the first and second passages 48, 49. The air passage extends from the air inlet openings 32 in the base 30 of the holder 14 of the current collector through the second passage 49 and through the first passage 48 to the opening 38 at the mouthpiece end. The air passage allows air to be drawn through the cartridge 10 from the connecting end to the mouthpiece end.

In the storage configuration as shown in Fig. 15a, the base 30 of the current collector holder 14 extends beyond the outer housing 36, and the piercing elements 34 of the current collector holder 14 are located at a distance from the seal 52 in the direction of the connecting end of the cartridge 10. In this configuration, the liquid substrate 42 that forms the aerosol is held in the first part 44 of the liquid reservoir 40 and is isolated from the second part 46 of the liquid reservoir 40 by means of the seal 52.

In the configuration of use, as shown in Fig. 15b, the current collector holder 14 and the current collector assembly 12 are inserted into the outer housing 36 in the direction of the mouthpiece end. As the current collector holder 14 moves toward the mouthpiece end of the outer housing 36, the seal 50 at the base 30 of the current collector holder 14 slides along the inner surface of the outer housing 36, maintaining an airtight seal between the inner surface of the outer housing 36 and the outer surface of the tubular current collector holder body, while the base of the current collector holder 14 is placed in the outer housing. As the piercing elements 34 of the holder 14 of the current collector move toward the mouthpiece end, the piercing elements 34 contact and pierce the seal 52, providing fluid communication between the first part 44 of the reservoir 40 for liquid and the second part 46 of the reservoir 40 for liquid. The liquid substrate 42, which forms the aerosol, in the first part 44 of the reservoir 40 for liquid is released into the second part 46 of the reservoir 40 for liquid, and the current collecting unit 12 is open for the liquid substrate 42, which forms the aerosol. In the configuration of using the region 22 of fastening the current collecting elements and the corresponding parts of the wick element, which extend into the second part 46 of the reservoir 40 for liquid, are capable of drawing the liquid substrate 42, which forms the aerosol, from the second part 46 of the reservoir 40 for liquid in the heating regions 24 of the current collecting elements.

Fig. 16a and 16b show an aerosol generating system comprising a cartridge 10 according to Fig. 15a and 15b in a use configuration placed in an aerosol generating device 60. Fig. 16b shows the aerosol generating system according to Fig. 16a rotated 90 degrees relative to the longitudinal axis of the system. The aerosol generating device 60 is substantially similar to the aerosol generating device 60 shown in Fig. 1a and 1b, and like features are designated by like reference numerals.

The aerosol generating device 60 comprises a generally cylindrical housing 62 comprising a connecting end and a distal end opposite the connecting end. A cavity 64 for receiving the connecting end of the cartridge is located at the connecting end of the device 60, and an air inlet 65 is provided in the outer housing at the base of the cavity 64 to ensure that ambient air is drawn into the cavity 64 at the base.

The device 60 further comprises an induction heating device housed in a housing 62. The induction heating device comprises two pairs of induction coils, a control circuit 70 and a power source 72. In Fig. 16b, only one pair of induction coils 90, 91 is visible. The power source 72 comprises a rechargeable nickel-cadmium battery that is recharged through an electrical connector (not shown) at the far end of the device. The control circuit 70 is connected to the power source 72 and also to the induction coil 66, such that the control circuit 70 controls the supply of power to the induction coil 66. The control circuit 70 is configured to supply alternating current to the induction coil 66.

The induction coils comprise a pair of opposing flat induction coils located around each current-receiving unit 12 when the cartridge 10 is placed in the cavity 64. The induction coils have a size and shape corresponding to the size and shape of the heating areas of the current-receiving elements.

The induction coils 90, 91 are designed in such a way that when alternating current is supplied to the induction coils, the induction coils generate opposite alternating magnetic fields on opposite sides of the current-receiving units 12. The alternating magnetic fields generated by the induction coils are directed substantially perpendicular to the plane of the current-receiving units 12 and the current-receiving elements.

During operation, when the user takes a puff through the opening 38 at the mouthpiece end of the cartridge 10, ambient air is drawn into the base of the cavity 64 through the air inlet opening 65 and into the cartridge 10 through the air inlet openings 32 in the base 30 of the cartridge 10, as shown by the arrows in Fig. 10a. The ambient air passes through the cartridge 10 from the base 30 to the opening 38 at the mouthpiece end through the air passage and over the current collecting assemblies 12.

The control circuit 70 controls the supply of electric power from the power source 72 to the induction coils 90, 91 upon activation of the system. The control circuit 72 may comprise an air flow sensor (not shown), and the control circuit 72 may supply electric power to the induction coil 66 when the air flow sensor detects puffs taken by the user from the cartridge 10.

When the system is activated, an alternating current is established in each of the induction coils 90, 91, which generates alternating magnetic fields in the cavity 64, penetrating into the current-receiving unit 12, causing heating of the heating areas of the current-receiving elements. The liquid substrate, forming an aerosol, in the second part 44 of the liquid reservoir 40 is drawn into the current-receiving units 12 through the wick elements to the heating areas of the current-receiving elements. The liquid substrate, forming an aerosol, is heated in the heating areas of the current-receiving elements, and volatile compounds from the heated aerosol-forming substrate are released into the air passage of the cartridge 10, which cools with the formation of an aerosol. The aerosol is entrained by air drawn through the air passage of the cartridge 10 and is drawn out of the cartridge 10 through the opening 38 at the mouthpiece end for inhalation by the user.

Fig. 17a and 17b show a current collecting element according to another embodiment of the invention.

The current-collecting element 100 comprises a woven mesh of threads. Some of the woven threads 102 extend in the warp direction, and some of the woven threads 104 extend in the weft direction, substantially perpendicular to the warp direction.

The threads 104 running in the weft direction contain a magnetic material, such as stainless steel AISI 409. The threads 102 running in the warp direction contain a non-magnetic material, such as stainless steel AISI 316. The mesh is sintered in such a way that electrical connections are created at the contact points between the threads 102 running in the warp direction and the threads 104 running in the weft direction.

The current-collecting element 100 is a flat element extending substantially in a plane. The threads 102 extending in the warp direction are interwoven with the threads 104 extending in the weft direction such that the threads 102 extending in the warp direction extend further outward from the plane of the current-collecting element 100 than the threads 104 extending in the weft direction. In other words, the threads 102 extending in the warp direction determine the maximum thickness of the current-collecting element 100.

Since the threads 102 running in the warp direction determine the maximum thickness of the current collecting member 100, the current collecting member holder 14, which is in contact with the current collecting member 100, comes into contact only with the threads 102 running in the warp direction, as shown in Fig. 17a.

Since the warp-directed threads 102 are not composed of a magnetic material, the warp-directed threads 102 are not directly heated by eddy current induction or hysteresis losses when the current-collecting member 100 is exposed to an alternating magnetic field.

For the purposes of the present description and the appended claims, except where otherwise indicated, all numbers expressing quantities, amounts, percentages, etc., are to be understood as modified in all instances by the term "about." Also, all ranges include the disclosed maximum and minimum points and include any intermediate ranges therebetween, which may or may not be specifically listed herein. Therefore, in this context, the number A is understood as A ± {5%} A. In this context, the number A can be considered to include numerical values that are within the normal standard error for measuring the property that the number A modifies. The number A, in some instances, when used in the appended claims, may deviate by the percentages listed above, provided that the amount by which A deviates does not materially affect the fundamental and novel characteristic(s) of the claimed invention. Also, all ranges include the disclosed maximum and minimum points and include any intermediate ranges therebetween, which may or may not be specifically listed herein.

Claims (32)

1. An electrically heated aerosol generating system comprising: at least one induction coil; a power source connected to at least one induction coil and configured to supply alternating current to at least one induction coil to generate an alternating magnetic field; a housing containing a reservoir with an aerosol-forming substrate; and a substantially flat susceptor assembly capable of being heated by means of an alternating magnetic field and comprising a first susceptor element, a second susceptor element and a wick element in fluid communication with a reservoir, wherein the first and second susceptor elements are formed as a single unit with the wick element or are attached to it; wherein a space is formed between the first and second susceptor elements, the wick element occupies said space, and wherein the reservoir is located outside of said space, and wherein the first and second susceptor elements are permeable to the fluid medium. 2. An electrically heated aerosol generating system according to claim 1, characterized in that the susceptor unit or the heating region of the susceptor unit are designed with the ability to hold from 2 to 10 ml of a liquid substrate that forms an aerosol. 3. An electrically heated aerosol generating system according to claim 1 or 2, characterized in that each of the first and second susceptor elements comprises a mesh, a flat spiral coil, fibers or fabric made of electrically conductive threads. 4. An electrically heated aerosol generating system according to claim 1 or 2, characterized in that each of the first and second susceptor elements contains an electrically conductive material printed or applied to the wick element in the form of a film or a plurality of tracks. 5. An electrically heated aerosol generating system according to claim 1 or 2, characterized in that each of the first and second susceptor elements comprises a perforated foil. 6. An electrically heated aerosol generating system according to any one of the preceding claims, characterized in that the substantially flat susceptor assembly extends parallel to the first plane, and wherein the system is configured such that at least one induction coil provides a magnetic field on the susceptor assembly that is perpendicular to the first plane. 7. An electrically heated aerosol generating system according to any one of the preceding claims, characterized in that the aerosol generating system further comprises an air flow passage extending between the air inlet and the air outlet, wherein the air flow in the air flow passage passes through a surface of the first susceptor element and a surface of the second susceptor element. 8. An electrically heated aerosol generating system according to claim 7, wherein the reservoir comprises a fluid channel extending in the direction of the susceptor unit. 9. An electrically heated aerosol generating system according to claim 7 or 8, characterized in that the housing comprises an inner wall and an outer wall, such that the inner passage is formed by the inner wall, and the inner passage is surrounded by a space formed between the inner wall and the outer wall. 10. An electrically heated aerosol generating system according to claim 9, wherein the air flow passage is at least partially defined by an internal passage and the reservoir at least partially surrounds the internal passage. 11. An electrically heated aerosol generating system according to claim 9, characterized in that the reservoir is at least partially formed by an internal passage, and the passage for the air flow is at least partially formed by an annular space. 12. An electrically heated aerosol generating system according to any one of the preceding claims, characterized in that the susceptor unit is surrounded by a fluid-permeable electrically insulating coating. 13. An electrically heated aerosol generating system according to any of the preceding claims, characterized in that the susceptor unit has a thickness of no more than two millimeters. 14. An electrically heated aerosol generating system according to any one of the preceding claims, characterized in that it further comprises a susceptor unit holder on which the susceptor unit is mounted. 15. An electrically heated aerosol generating system according to claim 14, characterized in that the susceptor unit holder is tubular and has at least one side wall. 16. An electrically heated aerosol generating system, characterized in that it comprises an aerosol generating device and a cartridge adapted for use with said device; wherein said aerosol generating device comprises: at least one induction coil; a power source connected to at least one induction coil and configured to supply alternating current to at least one induction coil to generate an alternating magnetic field; and a device body configured to engage with at least a portion of a cartridge when the cartridge is used with said aerosol generating device; and wherein the cartridge comprises a substantially flat susceptor assembly and a cartridge housing, wherein the substantially flat susceptor assembly is configured to be heated by means of an alternating magnetic field and comprises a first susceptor element, a second susceptor element and a wick element in fluid communication with a reservoir, wherein the first and second susceptor elements are formed as a single unit with the wick element or are attached to it; wherein a space is formed between the first and second susceptor elements, the wick element occupies said space, and wherein the reservoir is located outside of said space; and wherein the first and second susceptor elements are permeable to the fluid; wherein at least one induction coil is located around or near the susceptor assembly when the cartridge is engaged with the aerosol generating device. 17. A cartridge for use in an electrically heated aerosol generating system, wherein the electrically heated aerosol generating system comprises an aerosol generating device, wherein the cartridge is configured to be used with the device, wherein the device comprises: a device housing configured to engage with at least a portion of the cartridge when the cartridge is used with the aerosol generating device; at least one induction coil; and a power source connected to the at least one induction coil and configured to supply an alternating current to the at least one induction coil such that the induction coil generates an alternating magnetic field within the cartridge; wherein the cartridge comprises: a cartridge body that forms a reservoir containing an aerosol-forming substrate; and a substantially flat susceptor assembly capable of being heated by means of an alternating magnetic field and comprising a first susceptor element, a second susceptor element and a wick element in fluid communication with a reservoir, wherein the first and second susceptor elements are formed as a single unit with the wick element or are attached to it; wherein a space is formed between the first and second susceptor elements, wherein the wick element occupies said space, and wherein the reservoir is located outside of said space; and wherein the first and second susceptor elements are permeable to the fluid medium.