WO2013131764A1

WO2013131764A1 - Heating smokable material

Info

Publication number: WO2013131764A1
Application number: PCT/EP2013/053566
Authority: WO
Inventors: Petr Alexandrovich EGOYANTS; Dmitry Mikhailovich VOLOBUEV; Pavel Nikolaevich FIMIN; Oleg Jurievich ABRAMOV
Original assignee: British American Tobacco Investments Ltd IFI; British American Tobacco Co Ltd
Current assignee: British American Tobacco Investments Ltd IFI
Priority date: 2012-03-05
Filing date: 2013-02-22
Publication date: 2013-09-12
Anticipated expiration: 2014-09-05

Description

Heating Smokable Material

Field

The invention relates to heating smokable material.

Background

Smoking articles such as cigarettes and cigars burn tobacco during use to create tobacco smoke. Attempts have been made to provide alternatives to these smoking articles by creating products which release compounds without creating tobacco smoke. Examples of such products are so-called heat-not-burn products which release compounds by heating, but not burning, tobacco.

Summary

According to the invention, there is provided an apparatus configured to heat smokable material to volatilize at least one component of the smokable material, comprising thermal insulation with a heater arranged integrally therein.

The thermal insulation may be vacuum insulation. The insulation and heater may define an internal smokable material heating chamber in which the heater is arranged to heat smokable material.

The heater and insulation may extend along a longitudinal axis of the apparatus and may be located substantially co-axially outwardly of the heating chamber.

The heater may be located in at least one recess in a surface of the insulation facing the smokable material heating chamber.

The smokable material heating chamber may be substantially tubular.

An inwardly-facing surface of the heater may be substantially flush with an inwardly- facing surface of the insulation. The heater may comprise a plurality of sectional heating regions aligned along the longitudinal axis of the apparatus.

The plurality of heating regions may be separated by regions of the insulation.

The plurality of heating regions may be substantially surrounded by the insulation on all sides other than a side facing the smokable material.

The plurality of heating regions may be ring-shaped.

Each of the plurality of heating regions may be configured to heat a different section of smokable material.

According to the invention, there is provided thermal insulation configured to thermally insulate a heating chamber, wherein the thermal insulation comprises a heater.

The insulation may be vacuum insulation. The heater may comprise a sectional heater arranged to heat smokable material in the chamber.

According to the invention, there is provided a method of heating smokable material to volatilize at least one component of the smokable material, comprising insulating a smokable material heating chamber with thermal insulation having a heater arranged integrally therein.

According to an aspect of the invention, there is provided an apparatus configured to heat smokable material to volatilize at least one component of the smokable material, comprising an infra-red heater.

The infra-red heater may comprise a halogen infra-red heater. For exemplary purposes only, embodiments of the invention are described below with reference to the accompanying figures in which:

Brief description of the figures

Figure 1 is a schematic illustration of an apparatus configured to heat smokable material, comprising thermal insulation and a heater arranged integrally with the insulation;

figure 2 is a flow diagram showing a method of activating heating regions and opening and closing heating chamber valves during puffing;

figure 3 is a graphical illustration of a heating pattern which can be used to heat smokable material using a heater;

figure 4 is a schematic, cross-sectional illustration of a section of vacuum insulation configured to insulate heated smokable material from heat loss;

figure 5 is another schematic, cross-sectional illustration of a section of vacuum insulation configured to insulate heated smokable material from heat loss; and figure 6 is a schematic, cross-sectional illustration of a heat resistive thermal bridge which follows an indirect path from a higher temperature insulation wall to a lower temperature insulation wall. Detailed description

As used herein, the term 'smokable material' includes any material that provides volatilized components upon heating and includes any tobacco-containing material and may, for example, include one or more of tobacco, tobacco derivatives, expanded tobacco, reconstituted tobacco or tobacco substitutes.

Referring to figure 1, an apparatus 1 for heating smokable material comprises an energy source 2, a heater 3 and a heating chamber 4. The energy source 2 may comprise a battery such as a Li-ion battery, Ni battery, Alkaline battery and/ or the like, and is electrically coupled to the heater 3 to supply electrical energy to the heater 3 when required. The heating chamber 4 is configured to receive smokable material 5 so that the smokable material 5 can be heated in the heating chamber 4. The heating chamber 4 is located adjacent to the heater 3 so that thermal energy from the heater 3 heats the smokable material 5 therein to volatilize aromatic compounds and nicotine in the smokable material 5, without burning the smokable material 5. A mouthpiece 6 is provided through which a user of the apparatus 1 can inhale the volatilized compounds during use of the apparatus 1. The smokable material 5 may comprise a tobacco blend.

A housing 7 may contain components of the apparatus 1 such as the energy source 2 and heater 3. The housing 7 may comprise an approximately cylindrical tube with the energy source 2 located towards its first end 8 and the heater 3 and heating chamber 4 located towards its opposite, second end 9. The energy source 2 and heater 3 extend along the longitudinal axis of the housing 7. For example, the energy source 2 and heater 3 can extend along the longitudinal axis of the housing 7 in an end-to-end arrangement so that an end face of the energy source 2

substantially faces an end face of the heater 3. Heat insulation may be provided between the energy source 2 and the heater 3 to prevent direct transfer of heat from one to the other. The length of the housing 7 may be approximately 130mm, the length of energy source may be approximately 59mm, and the length of the heater 3 and heating region 4 may be approximately 50mm. The diameter of the housing 7 may be between approximately 9mm and 18mm. For example, the diameter of the first end 8 of the housing may be approximately 15mm whilst the diameter of the mouthpiece 6 at the second end 9 of the housing may be approximately 9mm. The external diameter of the heater 3 may be between approximately 9.0mm and approximately 13.0mm. The diameter of the heating chamber 4 may be between approximately 5.0mm and approximately 8mm, such as a diameter between 3.0mm and 6.00 mm. The diameter of the energy source 2 may be between approximately 14.0mm and approximately 15.0mm, such as 14.6mm, although other diameters of energy source 2 could equally be used.

The mouthpiece 6 can be located at the second end 9 of the housing 7, adjacent the heating chamber 4 and smokable material 5. The housing 7 is suitable for being gripped by a user during use of the apparatus 1 so that the user can inhale volatilized smokable material compounds from the mouthpiece 6 of the apparatus 1. The heater 3 may comprise a ceramics heater 3. The ceramics heater 3 may, for example, comprise base ceramics of alumina and/ or silicon nitride which are laminated and sintered. Alternatively, the heater 3 may comprise an infra-red (IR) heater 3 such as a halogen-IR lamp 3. The IR heater 3 may have a low mass and therefore its use can help to reduce the overall mass of the apparatus 1. For example, the mass of the IR heater may be 20% to 30% less than the mass of a ceramics heater 3 having an equivalent heating power output. The IR heater 3 also has low thermal inertia and therefore is able to heat the smokable material 5 very rapidly in response to an activation stimulus. The IR heater 3 may be configured to emit IR electromagnetic radiation of between approximately 700nm and 4.5 μπι in wavelength. Another alternative is to use a resistive heater 3, such as a resistive wire wound on a ceramic insulation layer deposited on a wall of the thermal insulation 18 referred to below. As shown in figure 1, the heater 3 may comprise a plurality of individual heating regions 10. The heating regions 10 may be operable independently of one another so that different regions 10 can be activated at different times to heat the smokable material 5. The heating regions 10 may be arranged in the heater 3 in any geometric arrangement. However, in the example shown in figure 1 , the heating regions 10 are geometrically arranged in the heater 3 so that different ones of the heating regions 10 are arranged to predominately and independently heat different regions of the smokable material 5.

For example, referring to figure 1, the heater 3 may comprise a plurality of axially aligned heating regions 10 in a substantially elongate arrangement. The regions 10 may each comprise an individual element of the heater 3. The heating regions 10 may, for example, all be aligned with each other along a longitudinal axis of the heater 3, thus providing a plurality of independent heating zones along the length of the heater 3. Each heating region 10 may comprise a hollow heating cylinder 10, which may be a ring 10, having a finite length which is significantly less than the length of the heater 3 as a whole. The arrangement of axially aligned heating regions 10 define the exterior of the heating chamber 4 and are configured to heat smokable material 5 located in the heating chamber 4. The heat is applied inwardly, predominately towards the central longitudinal axis of the heating chamber 4. The heating regions 10 are arranged with their radial, or otherwise transverse, surfaces facing one another along the length of the heater 3. The transverse surfaces of each heating region 10 may be separated from the transverse surfaces of its neighbouring heating region(s) 10 by thermal insulation 18, as shown in figure 1 and described below.

The heater 3 is integrated with the thermal insulation 18. For example, referring to figure 1 , the thermal insulation 18 may comprise a substantially elongate, hollow body, such as a substantially cylindrical tube of insulation 18, which is located co- axially around the heating chamber 4 and into which the heating regions 10 are integrated. The thermal insulation 18 may comprise a layer in which recesses are provided in the inwardly facing surface profile 21. Heating regions 10 are located in these recesses so that the heating regions 10 face the smokable material 5 in the heating chamber 4. The surfaces of the heating regions 10 which face the heating chamber 4 may be flush with the inside surface 21 of the thermal insulation 18 in regions of the insulation 18 which are not recessed.

Additionally, a heat reflecting layer may be present between the transverse surfaces of the heating regions 10. The arrangement of the heating regions 10 relative to each other may be such that thermal energy emitted from each one of the heating regions 10 does not substantially heat the neighbouring heating regions 10 and instead travels predominately inwardly from the circumferential surface of the heating region 10 into the heating chamber 4 and smokable material 5. Each heating region 10 may have substantially the same dimensions as the other regions 10. The integration of the heater 3 with the thermal insulation 18 means that the heating regions 10 are substantially surrounded by the insulation 18 on all sides of the heating regions 10 other than those which face inwardly towards the smokable material heating chamber 4. As such, heat emitted by the heater 3 is concentrated in the smokable material 5 and does not dissipate into other parts of the apparatus 1 or into the atmosphere outside the housing 7. The integration of the heater 3 with the thermal insulation 18 also reduces the thickness of the combination of heater 3 and thermal insulation 18 compared to providing the heater 3 separately and internally of a layer of thermal insulation 18. This can allow the diameter of the apparatus 1 , in particular the external diameter of the housing 7, to be reduced resulting in a conveniently sized slim-line product.

Alternatively, the reduction in thickness provided by the integration of the heater 3 with the thermal insulation 18 can allow a wider smokable material heating chamber 4 to be accommodated in the apparatus 1, or the introduction of further

components, without any increase in the overall width of the housing 7, as compared to a device in which the heater 3 is separate and positioned internally from a layer of thermal insulation 18.

The arrangement of the heating regions 10 is such that when a particular one of the heating regions 10 is activated, it supplies thermal energy to the smokable material 5 located radially inside the heating region 10 without substantially heating the remainder of the smokable material 5. The smokable material 5 can therefore be heated in independent sections, for example disks or substantially solid cylinders, where each section corresponds to smokable material 5 located directly inside a particular one of the heating regions 10 and has a mass and volume which is significantly less than the body of smokable material 5 as a whole.

As will be described further below, the heating regions 10 can each be individually and selectively activated.

The thermal insulation 18, which is provided between the smokable material 5 and an external surface 19 of the housing 7 as described above, reduces heat loss from the apparatus 1 and therefore improves the efficiency with which the smokable material 5 is heated. Referring to figure 4, the insulation 18 may comprise vacuum insulation 18. For example, the insulation 18 may comprise a layer which is bounded by a wall material 19 such as a metallic material. An internal region or core 20 of the insulation 18 may comprise an open-cell porous material, for example comprising polymers, aerogels or other suitable material, which is evacuated to a low pressure. The internal region 20 of the insulation 18 is configured to absorb gases which may be generated inside the region 20 to thereby maintain a vacuum state. The pressure in the internal region 20 may be in the range of 0.1 to 0.001 mbar. The wall 19 of the insulation 18 is sufficiently strong to withstand the force exerted against it due to the pressure differential between the core 20 and external surfaces of the wall 19, thereby preventing the insulation 18 from collapsing. The wall 19 may, for example, comprise a stainless steel wall 19 having a thickness of approximately ΙΟΟμπι. The thermal conductivity of the insulation 18 may be in the range of 0.004 to 0.005 W/mK. The heat transfer coefficient of the insulation 18 may be between approximately 1.10 W/(m²K) and approximately 1.40 W/(m²K) within a temperature range of between 100 degrees Celsius and 250 degrees Celsius, such as between approximately 150 degrees Celsius and approximately 250 degrees Celsius. The gaseous conductivity of the insulation 18 is negligible. A reflective coating may be applied to the internal surfaces of the wall material 19 to minimize heat losses due to radiation propagating through the insulation 18. The coating may, for example, comprise an aluminium IR reflective coating having a thickness of between approximately 0.3μπι and Ι .Ομπι. The evacuated state of the internal core region 20 means that the insulation 18 functions even when the thickness of the core region 20 is very small. The insulating properties are substantially unaffected by its thickness. This helps to reduce the overall size, particularly the diameter, of the apparatus 1.

As shown in figure 4, the wall 19 comprises an inwardly- facing section 21 and an outwardly-facing section 22. The inwardly-facing section 21 comprises the recesses in which the heating regions 10 of the heater 3 are accommodated as previously described and substantially faces the smokable material 5 and heating chamber 4. The outwardly-facing section 22 substantially faces the exterior of the housing 7. During operation of the apparatus 1, the inwardly-facing section 21 may be warmer due to the thermal energy originating from the heater 3, whilst the outwardly-facing section 22 is cooler due to the effect of the insulation 18. The inwardly-facing section 21 and the outwardly-facing section 22 may both comprise substantially longitudinally-extending walls 19 which are at least as long as the heater 3 and heating chamber 4, although the inwardly facing section 21 also comprises transversely extending regions as part of the recesses previously described. The internal surface of the outwardly-facing wall section 22, i.e. the surface facing the evacuated core region 20, may comprise a coating for absorbing gas in the core 20. A suitable coating is a titanium oxide film.

As illustrated in figure 1 , the overall length of the body of insulation 18 is greater than the length of the heating chamber 4 and heater 3 so as to further reduce heat loss from the apparatus 1 to the atmosphere outside the housing 7. For example, the thermal insulation 18 may be between approximately 70mm and approximately 80mm.

Referring to the schematic illustrations in figures 4 and 5, a thermal bridge 23 may connect the inwardly-facing wall section 21 to the outwardly-facing wall section 22 at the ends of the insulation 18 in order to completely encompass and contain the low pressure core 20. The thermal bridge 23 may comprise a wall 19 formed of the same material as the inwardly and outwardly-facing sections 21, 22. A suitable material is stainless steel, as previously discussed. The thermal bridge 23 has a greater thermal conductivity than the insulating core 20 and so has a greater potential to undesirably conduct heat out of the apparatus 1 and thereby reduce the efficiency with which the smokable material 5 is heated than the core 20.

To reduce heat losses due to the thermal bridge 23, the thermal bridge 23 may be extended to increase its resistance to heat flow from the inwardly- facing section 21 to the outwardly-facing section 22. This is schematically illustrated in figure 6. For example, the thermal bridge 23 may follow an indirect path between the inwardly- facing section 21 of the wall 19 and the outwardly-facing section 22 of the wall 19. The thermal bridge 23 is present at a longitudinal location in the apparatus 1 where the heater 3 and heating chamber 4 are not present. This means that the thermal bridge 23 gradually extends from the inwardly-facing section 21 to the outwardly- facing section 22 along the indirect path, thereby reducing the thickness of the core 20 to zero, at a longitudinal location in the housing 7 where the heater 3, heating chamber 4 and smokable material 5 are not present, thereby further limiting the conduction of heat out of the apparatus 1. The smokable material 5 may be comprised in a cartridge 11 which can be inserted into the heating chamber 4. The length of the cartridge 11 may be approximately equal to the length of the heater 3 so that the heater 3 can heat the cartridge 11 along its whole length.

The housing 7 of the apparatus 1 may comprise an opening through which the cartridge 11 can be inserted into the heating chamber 4. The opening may, for example, comprise an opening located at the second end 9 of the housing 7 so that the cartridge 11 can be slid into the opening and pushed directly into the heating chamber 4. The opening is preferably closed during use of the apparatus 1 to heat the smokable material 5. Alternatively, a section of the housing 7 at the second end 9 is removable from the apparatus 1 so that the smokable material 5 can be inserted into the heating chamber 4. The apparatus 1 may optionally be equipped with a user-operable smokable material ejection unit, such as an internal mechanism configured to slide used smokable material 5 out of the heating chamber 4. The used smokable material 5 may, for example, be pushed back through the opening in the housing 7. A new cartridge 11 can then be inserted as required. Alternatively, the heater 3, heating chamber 4 and smokable material 5 may be comprised in a single disposable unit which electrically connects the energy source 2 to receive heating power and can be removed from the energy source 2 in one piece once the smokable material 5 has released a given quantity of certain components such as nicotine and aromatic compounds through heating. A fresh disposable unit can then be attached as desired.

The apparatus 1 may comprise a controller 12, such as a microcontroller 12, which is configured to control operation of the apparatus 1. The controller 12 is electronically connected to the other components of the apparatus 1 such as the energy source 2 and heater 3 so that it can control their operation by sending and receiving signals. The controller 12 is, in particular, configured to control activation of the heater 3 to heat the smokable material 5. For example, the controller 12 may be configured to activate the heater 3, which may comprise selectively activating one or more heating regions 10, in response to a user drawing on the mouthpiece 6 of the apparatus 1. In this regard, the controller 12 may be in communication with a puff sensor 13 via a suitable communicative coupling. The puff sensor 13 is configured to detect when a puff occurs at the mouthpiece 6 and, in response, is configured to send a signal to the controller 12 indicative of the puff. An electronic signal may be used. The controller 12 may respond to the signal from the puff sensor 13 by activating the heater 3 and thereby heating the smokable material 5. The use of a puff sensor 13 to activate the heater 3 is not, however, essential and other means for providing an activation stimulus to activate the heater 3, such as a user-operable actuator, can alternatively be used. The volatilized compounds released during heating can be inhaled by the user through the mouthpiece 6. The controller 12 can be located at any suitable position within the housing 7. An example position is between the energy source 2 and the heater 3/heating chamber 4. If the heater 3 comprises two or more heating regions 10 as described above, the controller 12 may be configured to activate the heating regions 10 in a

predetermined order or pattern. For example, the controller 12 may be configured to activate the heating regions 10 sequentially along the heating chamber 4. Each activation of a heating region 10 may be in response to an activation stimulus. An example stimulus is detection of a puff by the puff sensor 13, but the activation may be triggered in an alternative way such as by the elapse of a predetermined period of time after the activation of the previous heating region 10 or by elapse of a predetermined period of time after initial activation of the heater 3, as described further below.

Referring to figure 2, an example heating method may comprise a first step SI in which an activation stimulus, such as a first puff, is detected followed by a second step S2 in which a first section of smokable material 5 is heated in response to the first puff or other activation stimulus. In a third step S3, hermetically sealable inlet and outlet valves 24 may be opened to allow air to be drawn through the heating chamber 4 and out of the apparatus 1 through the mouthpiece 6. In a fourth step, the valves 24 are closed. These valves 24 are described in more detail below with respect to figure 1. In fifth S5, sixth S6, seventh S7 and eighth S8 steps, a second section of smokable material 5 may be heated, for example in response to another activation stimulus such as a second puff, with a corresponding opening and closing of the heating chamber inlet and outlet valves 24. In ninth S9, tenth S10, eleventh Sl l and twelfth S12 steps, a third section of the smokable material 5 may be heated in response to detection of another activation stimulus, such as a third puff, with a corresponding opening and closing of the heating chamber inlet and outlet valves 24, and so on. Means other than a puff sensor 13 could alternatively be used. For example, a user of the apparatus 1 may actuate a control switch to indicate that he/ she is taking a new puff.

In this way, a fresh section of smokable material 5 may be heated to volatilize nicotine and aromatic compounds for each new puff or in response to a given quantity of certain components, such as nicotine and/ or aromatic compounds, from the previously heated section of smokable material 5. The number of heating regions 10 and/or independently heatable sections of smokable material 5 may correspond to the number of puffs for which the cartridge 11 is intended to be used. Alternatively, each independently heatable smokable material section 5 may be heated by its corresponding heating region(s) 10 for a plurality of puffs such as two, three or four puffs, so that a fresh section of smokable material 5 is heated only after a plurality of puffs have been taken whilst heating the previous smokable material section.

As referred to briefly above, instead of activating each heating region 10 in response to an individual puff, the heating regions 10 may alternatively be activated sequentially over a predetermined period of use, one after the other, in response to an initial activation stimulus such as a single, initial puff at the mouthpiece 6. For example, the heating regions 10 may be activated at regular, predetermined intervals over the expected inhalation period for a particular smokable material cartridge 11. The predetermined intervals may correspond to the period which is taken to release a given amount of certain components such as nicotine and/ or aromatic

compounds from each smokable material section. An example interval is between approximately 60 and 240 seconds. Therefore, at least the fifth and ninth steps S5, S9 shown in figure 2 are optional. Each heating region 10 may continue to be activated for a predetermined period, which may correspond to the lengths of the intervals referred to above or may be longer, as described below. Once all of the heating regions 10 have been activated for a particular cartridge 11, the controller 12 may be configured to indicate to the user that the cartridge 11 should be changed. The controller 12 may, for example, activate an indicator light at the external surface of the housing 7.

It will be appreciated that activating individual heating regions 10 in order rather than activating the entire heater 3 means that the energy required to heat the smokable material 5 is reduced over what would be required if the heater 3 were activated fully over the entire inhalation period of a cartridge 11. Therefore, the maximum required power output of the energy source 2 is also reduced. This means that a smaller and lighter energy source 2 can be installed in the apparatus 1. The controller 12 may be configured to de-activate the heater 3, or reduce the power being supplied to the heater 3, in between puffs. This saves energy and extends the life of the energy source 2. For example, upon the apparatus 1 being switched on by a user or in response to some other stimulus, such as detection of a user placing their mouth against the mouthpiece 6, the controller 12 may be configured to cause the heater 3, or next heating region 10 to be used to heat the smokable material 5, to be partially activated so that it heats up in preparation to volatilize components of the smokable material 5. The partial activation does not heat the smokable material 5 to a sufficient temperature to volatilize nicotine. A suitable temperature is below 120°C, such as 100°C or below. An example is a temperature of between 60°C and 100°C, such as a temperature between 80°C and

100°C. The temperature may be less than 100°C. In response to detection of a puff by the puff sensor 13, or some other stimulus such as the elapse of a predetermined time period, the controller 12 may then cause the heater 3 or heating region 10 in question to heat the smokable material 5 further in order to rapidly volatilize the nicotine and other aromatic compounds for inhalation by the user. If the smokable material 5 comprises tobacco, a suitable temperature for volatilizing the nicotine and other aromatic compounds may be 100°C or above, such as 120°C or above. An example is a temperature between 100°C and 250°C, such as between 150°C and 250°C or between 130°C and 180°C. The temperature may be more than 100°C. An example full activation temperature is 150°C, although other values such as 120°C and 250 °C are also possible. A super-capacitor can optionally be used to provide the peak current used to heat the smokable material 5 to the volatization

temperature. An example of a suitable heating pattern is shown in figure 3, in which the peaks may respectively represent the full activation of different heating regions 10. As can be seen, the smokable material 5 is maintained at the

volatization temperature for the approximate period of the puff which, in this example, is two seconds.

Three example operational modes of the heater 3 are described below.

In a first operational mode, during full activation of a particular heating region 10, all other heating regions 10 of the heater are deactivated. Therefore, when a new heating region 10 is activated, the previous heating region is deactivated. Power is supplied only to the activated region 10. The heating regions 10 are activated sequentially along the length of the heater 3 so that nicotine and aromatic compounds are regularly released from fresh portions of smokable material 5 until the cartridge 11 is exhausted. This mode provides more uniform nicotine and smokable material flavour delivery than by fully activating all of the heating regions 10 for the duration of the heating period of the cartridge 11.

Alternatively, in a second operational mode, once a particular heating region 10 has been activated, it remains fully activated until the heater 3 is switched off.

Therefore, the power supplied to the heater 3 incrementally increases as more of the heating regions 10 are activated during inhalation from the cartridge 11. The continuing activation of the heating regions 10 throughout the chamber 4 substantially prevents condensation of components such as nicotine volatized from the smokable material 5 in the heating chamber 4.

Alternatively, in a third operational mode, during full activation of a particular heating region 10, one or more of the other heating regions 10 may be partially activated. Partial activation of the one or more other heating regions 10 may comprise heating the other heating region(s) 10 to a temperature which is sufficient to substantially prevent condensation of components such as nicotine volatized from the smokable material 5 in the heating chamber 4. The temperature of the heating regions 10 which are partially activated is less than the temperature of the heating region 10 which is fully activated. The smokable material 10 located adjacent to the partially activated regions 10 is not heated to a temperature sufficient to volatize components of the smokable material 5. For example, upon full activation of a new heating region 10, the previously fully activated heating region 10 is partially but not fully deactivated so as to continue to heat its adjacent smokable material 5 at a lower temperature and thus prevent condensation of volatized components in the heating chamber 4. Retaining the previous heating regions 10 in a partially rather than fully activated state prevents the smokable material 5 adjacent those regions 10 from becoming overly toasted and thus avoids potential negative effects on the flavours experienced by the user of the apparatus 1.

For any of the alternatives described above, the heating regions 10 may either be heated to full operational temperature immediately after activation or may initially be heated to a lower temperature before being fully activated after a predetermined period of time to heat the smokable material 5 to volatize nicotine and other aromatic compounds.

Referring to figure 1, the apparatus 1 may comprise air inlets 14 which allow external air to be drawn into the housing 7 and through the heated smokable material 5 during puffing. The air inlets 14 may comprise apertures 14 in the housing 7 and may be located upstream from the smokable material 5 and heating chamber 4 towards the first end 8 of the housing 7. Air drawn in through the inlets 14 travels through the heated smokable material 5, via the inlet valves 24, and therein is enriched with smokable material vapours, such as aroma vapours, before passing through the outlet valves 24 and being inhaled by the user at the

mouthpiece 6. Optionally, as shown in figure 1, the apparatus 1 may comprise a heat exchanger 15 configured to warm the air before it enters the smokable material 5 and/ or to cool the air before it is drawn through the mouthpiece 6. For example, the heat exchanger 15 may be configured to use heat extracted from the air entering the mouthpiece 6 to warm new air before it enters the smokable material 5.

Referring to figure 1, as previously discussed, the heating chamber 4 insulated by the insulation 18 may comprise inlet and outlet valves 24, such as check valves, which hermetically seal the heating chamber 4 when closed. The valves 24 may be one-way valves, where the inlet valve 24 allows gaseous flow into the chamber 4 and the outlet valve 24 allows gaseous flow out of the chamber 4. Gaseous flow in the opposite direction is prevented. The valves 24 can thereby prevent air from undesirably entering and exiting the chamber 4 and can prevent smokable material flavours from exiting the chamber 4. The inlet and outlet valves 24 may, for example, be provided in the insulation 18. Between puffs, the valves 24 may be closed by the controller 12 or other means such a manual actuator so that all volatilized substances remain contained inside the chamber 4 in-between puffs. The partial pressure of the volatized substances between puffs reaches the saturated vapour pressure and the amount of evaporated substances therefore depends only on the temperature in the heating chamber 4. This helps to ensure that the delivery of volatilized nicotine and aromatic compounds remains constant from puff to puff. During puffing, the valves 24 open so that air can flow through the chamber 4 to carry volatilized smokable material components to the mouthpiece 6. Opening of the valves 24 may be caused by the controller 12 or by other means. A membrane can be located in the valves 24 to ensure that no oxygen enters the chamber 4. The valves 24 may be breath-actuated so that the valves 24 open in response to detection of a puff at the mouthpiece 6. The valves 24 may close in response to a detection that a puff has ended. Alternatively, the valves 24 may close following the elapse of a predetermined period after their opening. The predetermined period may be timed by the controller 12. Optionally, a mechanical or other suitable opening/ closing means may be present so that the valves 24 open and close automatically. For example, the gaseous movement caused by a user puffing on the mouthpiece 6 may exert a force on the valves 24 to cause them to open and close. Therefore, the use of the controller 12 is not required to actuate the valves 24. The mass of the smokable material 5 which is heated by the heater 3, for example by each heating region 10, may be in the range of 0.2 to .Og. The temperature to which the smokable material 5 is heated may be user controllable, for example to any temperature within the temperature range of 100°C to 250°C, such as any temperature within the range of 150°C to 250°C or the other volatizing temperature ranges as previously described. The mass of the apparatus 1 as a whole may be in the range of 70 to 125g. A battery 2 with a capacity of 1000 to 3000mAh and voltage of 3.7V can be used. The heating regions 10 may be configured to individually and selectively heat between approximately 10 and 40 sections of smokable material 5 for a single cartridge 11.

A benefit of integrating the heater 3 with the insulation 18 is that the size and weight of the heater 3 can be reduced compared to devices in which there is no integration of heater and insulation. Reduction of the heater size allows for a corresponding reduction in the diameter of the housing. Reduction of the heater weight, in turn, decreases the heating ramp-up time and thereby reduces the warming up time of the apparatus.

It will be appreciated that any of the alternatives described above can be used singly or in combination. The use of the thermal insulation 18 with a heater 3 therein is not restricted to the devices which are configured to heat smokable material. For example, the thermal insulation and integral heater can be used in other types of inhalation devices, such as inhalers. In order to address various issues and advance the art, the entirety of this disclosure shows by way of illustration various embodiments in which the claimed invention(s) may be practiced and provide for superior smokable material heating apparatuses and methods. The advantages and features of the disclosure are of a representative sample of embodiments only, and are not exhaustive and/ or exclusive. They are presented only to assist in understanding and teach the claimed features. It is to be understood that advantages, embodiments, examples, functions, features, structures, and/or other aspects of the disclosure are not to be considered limitations on the disclosure as defined by the claims or limitations on equivalents to the claims, and that other embodiments may be utilised and modifications may be made without departing from the scope and/ or spirit of the disclosure. Various embodiments may suitably comprise, consist of, or consist essentially of, various combinations of the disclosed elements, components, features, parts, steps, means, etc. In addition, the disclosure includes other inventions not presently claimed, but which may be claimed in future.

Claims

1. An apparatus configured to heat smokable material to volatilize at least one component of the smokable material, comprising thermal insulation with a heater arranged integrally therein.

2. An apparatus according to claim 1, wherein the thermal insulation is vacuum insulation.

3. An apparatus according to claim 1 or 2, wherein the insulation and heater define an internal smokable material heating chamber in which the heater is arranged to heat smokable material.

4. An apparatus according to claim 3, wherein the heater and insulation extend along a longitudinal axis of the apparatus and are located substantially co-axially outwardly of the heating chamber.

5. An apparatus according to claim 3 or 4, wherein the heater is located in at least one recess in a surface of the insulation facing the smokable material heating chamber.

6. An apparatus according to any of claims 3 to 5, wherein the smokable material heating chamber is substantially tubular.

7. An apparatus according to any preceding claim, wherein an inwardly- facing surface of the heater is substantially flush with an inwardly-facing surface of the insulation.

8. An apparatus according to any preceding claim, wherein the heater comprises a plurality of sectional heating regions aligned along the longitudinal axis of the apparatus.

9. An apparatus according to claim 8, wherein the plurality of heating regions are separated by regions of the insulation.

10. An apparatus according to claim 8 or 9, wherein the plurality of heating regions are substantially surrounded by the insulation on all sides other than a side facing the smokable material.

11. An apparatus according to any of claims 8 to 10, wherein the plurality of heating regions are ring-shaped.

12. An apparatus according to any of claims 8 to 11, wherein each of the plurality of heating regions is configured to heat a different section of smokable material.

13. Thermal insulation configured to thermally insulate a heating chamber, wherein the insulation comprises a heater.

14. Thermal insulation according to claim 13, wherein the insulation is vacuum insulation.

15. Thermal insulation according to claim 13 or 14, wherein the heater comprises a sectional heater arranged to heat smokable material in the chamber.

16. A method of heating smokable material to volatilize at least one component of the smokable material, comprising providing a smokable material heating chamber with thermal insulation having a heater arranged integrally therein.