EP4694712A1

EP4694712A1 - An aerosol generating device

Info

Publication number: EP4694712A1
Application number: EP24716803.2A
Authority: EP
Inventors: Alec WRIGHT; Grzegorz Aleksander PILATOWICZ; Jaakko MCEVOY
Original assignee: JT International SA
Current assignee: JT International SA
Priority date: 2023-04-13
Filing date: 2024-04-05
Publication date: 2026-02-18
Also published as: KR20250163899A; WO2024213480A1; JP2026506816A

Abstract

An aerosol generating device (10) has a proximal end (12), a distal end (14) and a longitudinal axis extending between the proximal end (12) and the distal end (14). The aerosol generating device (10) comprises a heating chamber (16) positioned towards the proximal end (12) for receiving an aerosol generating substrate (30) and a vapour chamber (42) containing a working fluid. The vapour chamber (42) has first and second end regions (44, 46) and is arranged to transfer heat from the first end region (44) to the second end region (46) by evaporation of the working fluid inside the vapour chamber (42) at the first end region (44) and condensation of the working fluid inside the vapour chamber (42) at the second end region (46). The first end region (44) is positioned at or adjacent to the proximal end (12) of the aerosol generating device (10) and the second end region (46) is positioned away from the proximal end (12).

Description

AN AEROSOL GENERATING DEVICE

Technical Field

The present disclosure relates generally to an aerosol generating device, and more particularly to an aerosol generating device for heating an aerosol generating substrate to generate an aerosol for inhalation by a user. The present disclosure is particularly applicable to a portable (hand-held) aerosol generating device, which may be self- contained and low temperature. Such devices may heat, rather than bum, an aerosol generating substrate to generate an aerosol for inhalation.

Technical Background

The popularity and use of reduced-risk or modified-risk devices (also known as vaporisers) has grown rapidly in recent years as an alternative to the use of traditional tobacco products. Various devices and systems are available that heat or warm, rather than bum, an aerosol generating substrate to generate an aerosol for inhalation by a user.

A commonly available reduced-risk or modified-risk device is an aerosol generating device, or so-called heat-not-bum device. Devices of this type generate an aerosol or vapour by heating an aerosol generating substrate, for example comprised in an aerosol generating article, to a temperature typically in the range 150°C to 300°C, in a heating chamber. Heating the aerosol generating substrate to a temperature within this range, without burning or combusting the aerosol generating substrate, generates a vapour which typically cools and condenses to form an aerosol for inhalation by a user of the device.

Inadequate thermal management can result in an increased temperature of component parts of the device, and this can be particularly problematic if the heating chamber is positioned at, or close to, the proximal end (i.e., mouth end) of the device because it can become too hot for a user to comfortably engage with their lips. There is, therefore, a need to provide an aerosol generating device which mitigates this drawback. WO 2019/151694 Al describes an electrically-operated aerosol generating device 30 (of which only an upper, or proximal, part is shown in Figure 3) comprising a case 310, a thin-film heater 320, a transfer pipe 330 which defines an airflow path through the device 30, and a heat transfer medium 340. The case 310 forms the exterior of the aerosol generating device 30 and is provided with a receiving space (i.e., a heating chamber) for accommodating an aerosol generating source, such as a cigarette.

The heat transfer medium 340 may be a heat pipe in which a refrigerant (e.g., water) is contained as the ‘working fluid’ inside an external metal material. When heat is applied to one end of the heat pipe 340, the refrigerant evaporates allowing heat energy to move to the other end of the heat pipe 340 and, thus, the heat pipe 340 acts as a vapour chamber. The heat pipe 340 appears to have a first end region positioned at or adjacent to a proximal end of the aerosol generating device 30. The purpose of the heat pipe 340 is to transfer heat generated by the heater 320 to the periphery of the heater 320 and at least a portion of the transfer pipe 330. With this arrangement, the area surrounding the heater 320 and the transfer pipe 330 can be maintained at a sufficiently high temperature to reduce dropletization of aerosol without using an additional heater.

Summary of the Disclosure

According to a first aspect of the present disclosure, there is provided an aerosol generating device having a proximal end, a distal end and a longitudinal axis extending between the proximal end and the distal end, the aerosol generating device comprising: a heating chamber positioned towards the proximal end for receiving an aerosol generating substrate; and a vapour chamber containing a working fluid, the vapour chamber having first and second end regions and being arranged to transfer heat from the first end region to the second end region by evaporation of the working fluid inside the vapour chamber at the first end region and condensation of the working fluid inside the vapour chamber at the second end region, the first end region being positioned at or adjacent to the proximal end of the aerosol generating device and the second end region being positioned away from the proximal end. The aerosol generating device is adapted to heat the aerosol generating substrate, without burning the aerosol generating substrate, to volatise at least one component of the aerosol generating substrate and thereby generate a vapour which may cool and condense to form an aerosol for inhalation by a user of the aerosol generating device.

In general terms, a vapour is a substance in the gas phase at a temperature lower than its critical temperature, which means that the vapour can be condensed to a liquid by increasing its pressure without reducing the temperature, whereas an aerosol is a suspension of fine solid particles or liquid droplets, in air or another gas. It should, however, be noted that the terms ‘aerosol’ and ‘vapour’ may be used interchangeably in this specification, specifically with regard to the form of the inhalable medium that is generated for inhalation by a user.

The vapour chamber is partially filled with a liquid, e.g., water. The liquid in the vapour chamber (which acts as a working fluid) absorbs heat from the proximal end of the aerosol generating device where the heating chamber is located and is thereby heated and vaporised at the first end region of the vapour chamber during use of the aerosol generating device. Thus, the liquid in the vapour chamber evaporates at the first end region to form a vapour as it absorbs heat from the proximal end of the aerosol generating device, creating a vapour pressure difference between the first end region and the second end region. This vapour pressure difference causes a transfer of vapour from the first end region to the second end region of the vapour chamber. The heat is transferred from the vapour at the second end region, e.g., to a casing of the aerosol generating device, and as the vapour cools due to this transfer of heat, it condenses back into a liquid. The liquid then flows back to the first end region of the vapour chamber so that it can again absorb heat from the proximal end of the aerosol generating device.

The vapour chamber acts as a thermal energy transfer component and provides an effective and highly efficient way to transfer heat away from the proximal end (i.e. , mouth end) of the aerosol generating device, thus maintaining an acceptable temperature at the proximal end so that a user can comfortably engage the proximal end with their lips to inhale generated aerosol. Optional features will now be set out. These are applicable singly or in any combination with any aspect of the present disclosure.

The vapour chamber may be substantially planar. Accordingly, the aerosol generating device may have a compact shape and form. The vapour chamber may extend in a direction substantially parallel to the longitudinal axis of the aerosol generating device. This allows heat to be transferred efficiently from the proximal end of the aerosol generating device to a position away from the proximal end, and again may help to ensure that the aerosol generating device has a compact shape and form.

The first end region may include a substantially planar first contact surface which may be in contact with a substantially planar surface of a first component of the aerosol generating device at or adjacent to the proximal end of the aerosol generating device. By providing a first planar contact surface at the first end region of the vapour chamber, good contact can be achieved between the first planar contact surface and the first component, especially when the first component also includes a substantially planar surface. This allows heat to be transferred efficiently by conduction from the first component to the first end region of the vapour chamber.

The second end region may include a substantially planar second contact surface which may be in contact with a substantially planar surface of a second component of the aerosol generating device at a position away from the proximal end of the aerosol generating device. By providing a second planar contact surface at the second end region of the vapour chamber, good contact can be achieved between the second planar contact surface and the second component, especially when the second component also includes a substantially planar surface. This allows heat to be transferred efficiently by conduction from the second end region of the vapour chamber to the second component. In some examples, the second component may be a casing of the aerosol generating device. The substantially planar first contact surface and the substantially planar second contact surface may be coplanar. Thus, the vapour chamber may lie substantially in a single plane. This may facilitate manufacture and/or assembly of the aerosol generating device and/or may facilitate transport of the working fluid between the first and second end regions of the vapour chamber.

The substantially planar first contact surface may lie in a first plane. The substantially planar second contact surface may he in a second plane which may be offset from, and substantially parallel to, the first plane. This arrangement may allow greater flexibility in the design and manufacture of the aerosol generating device, and may in particular allow the substantially planar first and second contact surfaces to be arranged in contact with first and second components of the aerosol generating device which do not he in the same plane.

The first end region of the vapour chamber may be positioned adjacent to an outer surface of the heating chamber. The first end region of the vapour chamber may contact the outer surface of the heating chamber. The second end region of the vapour chamber may be positioned away from the heating chamber. Heat is transferred away from the heating chamber to a different position on the aerosol generating device by the vapour chamber. Thus, transfer of heat from the heating chamber to the proximal end of the aerosol generating device is minimised, thereby improving thermal management and ensuring that the temperature at the proximal end is maintained at an acceptable level from the viewpoint of user comfort.

The aerosol generating device may include a mouthpiece portion at the proximal end. The first end region of the vapour chamber may be positioned adjacent to the mouthpiece portion. The first end region of the vapour chamber may contact a surface of the mouthpiece portion. The second end region of the vapour chamber may be positioned away from the mouthpiece portion. Heat is transferred away from the mouthpiece portion to a different position on the aerosol generating device by the vapour chamber. Thus, the mouthpiece portion is maintained at an acceptable temperature so that a user can comfortably engage the mouthpiece portion with their lips to inhale generated aerosol.

The mouthpiece portion may be positioned downstream of the heating chamber in an aerosol flow direction through the aerosol generating device.

The heating chamber may include a heater. The heater may be configured to heat a substantially planar aerosol generating substrate. The heating chamber may be dimensioned to receive an aerosol generating article having a flat cuboid shape. Thus, the heating chamber may have a cuboid shape. Possibly, the heating chamber comprises a first heater, e.g., a first planar heater, and optionally a second heater, e.g., a second planar heater, and the aerosol generating substrate may be receivable in the heating chamber between the first planar heater and the second planar heater. Accordingly, the aerosol generating device may have a compact shape and form.

The aerosol generating device may include a power source, e.g., one or more batteries, and a controller.

The first heater and the optional second heater may be configured to generate heat using electrical resistive heating. Thus, the power source and the controller may be connected to the first heater and the optional second heater.

The first heater and the optional second heater may be configured to generate heat using inductive heating. Thus, the first heater and the optional second heater may each comprise an inductively heatable susceptor and the aerosol generating device may comprise an induction coil arranged to generate an alternating electromagnetic field for inductively heating the inductively heatable susceptor. The inductively heatable susceptor may comprise one or more, but not limited, of aluminium, iron, nickel, stainless steel and alloys thereof, e.g. Nickel Chromium or Nickel Copper. With the application of an electromagnetic field in its vicinity, the susceptor may generate heat due to eddy currents and magnetic hysteresis losses resulting in a conversion of energy from electromagnetic to heat. The aerosol generating device may include a casing. The casing may have an inner surface. The casing may have an outer surface. The second end region of the vapour chamber, and more particularly the substantially planar second contact surface, may contact the inner surface of the casing. This arrangement allows heat to be transferred, e.g., by conduction, efficiently from the second end region of the vapour chamber to the casing. The heat tends to be dissipated throughout the casing by conduction thereby avoiding localised hot spots and is transferred from the outer surface of the casing to the surrounding ambient air.

The casing may comprise a metal, for example aluminium. This may facilitate the dissipation of heat throughout the casing by conduction thereby further helping to avoid localised hot spots.

The vapour chamber may include a wick element to control the flow of the working fluid through the vapour chamber, and in particular to facilitate the transfer of condensed working fluid from the second end region to the first end region. The wick element helps to control the flow of the working fluid through the vapour chamber and may, therefore, result in improved heat transfer from the first end region to the second end region.

The aerosol generating substrate may comprise any type of solid or semi-solid material. Example types of aerosol generating solids include powder, granules, pellets, shreds, strands, particles, gel, strips, loose leaves, cut filler, porous material, foam material or sheets. The aerosol generating substrate may comprise plant derived material and in particular, may comprise tobacco. It may advantageously comprise reconstituted tobacco, for example including tobacco and any one or more of cellulose fibres, tobacco stalk fibres and inorganic fillers such as CaCO3. The reconstituted tobacco may comprise tobacco sheets of any kind (paper-like sheets, cast tobacco sheets, etc.) in full sheets being crimped, folded and/or rolled or sheet fragments, and in an orientated gathered form (e.g., parallel arrangement or weaved pattern of substantially identical sheet fragments) or in randomly arranged form (e.g., sheet fragments of various sizes and shapes in bulk mixed form as tobacco cut filler).

Consequently, the aerosol generating device may be referred to as a “heated tobacco device”, a “heat-not-bum tobacco device”, a “device for vaporising tobacco products”, a “T-vapour” device and the like, with this being interpreted as a device suitable for achieving these effects.

The aerosol generating substrate may comprise an aerosol-former. Examples of aerosolformers include polyhydric alcohols and mixtures thereof such as glycerine or propylene glycol. Typically, the non-liquid aerosol generating substrate may comprise an aerosol -former content of between approximately 5% and approximately 50% on a dry weight basis. In some embodiments, the non-liquid aerosol generating substrate may comprise an aerosol-former content of between approximately 10% and approximately 20% on a dry weight basis, and possibly approximately 15% on a dry weight basis.

Upon being heated, the aerosol generating substrate may release volatile compounds. The volatile compounds may include nicotine or flavour compounds such as tobacco flavouring.

Brief Description of the Drawings

Figure 1 is a diagrammatic cross-sectional front view of an example of an aerosol generating device with a mouthpiece portion in a closed position;

Figure 2 is a diagrammatic view looking towards a proximal end of the aerosol generating device of Figure 1 with the mouthpiece portion in the closed position;

Figure 3 is a diagrammatic cross-sectional front view of the aerosol generating device of Figure 1 with the mouthpiece portion in an open position;

Figure 4 is a diagrammatic cross-sectional side view of the aerosol generating device of Figures 1 to 3;

Figure 5 is a diagrammatic cross-sectional front view of another example of an aerosol generating device with the mouthpiece portion in a closed position; and Figure 6 is a diagrammatic cross-sectional side view of the aerosol generating device of Figure 5.

Detailed Description of Embodiments

Embodiments of the present disclosure will now be described by way of example only and with reference to the accompanying drawings.

Referring initially to Figures 1 to 4, there is shown diagrammatically an example of an aerosol generating device 10 having a proximal end 12, a distal end 14 and longitudinal axis extending between the proximal and distal ends 12. During use, a user typically orients the aerosol generating device 10 with the proximal end 12 upward and/or in a proximate position with respect to the user’s mouth and the distal end 14 downward and/or in a distal position with respect to the user’s mouth.

The aerosol generating device 10 comprises a heating chamber 16, a power source 18, for example one or more batteries, and a controller 20 which are all positioned in a housing 22 of the aerosol generating device 10. The housing 22 may include a casing 23 having an inner surface 23a and an outer surface 23b. The casing 23 typically comprises a metal, such as aluminium. The aerosol generating device 10 is a hand-held, portable, device, by which it is meant that a user is able to hold and support the device unaided, in a single hand.

The controller 20 includes electronic circuitry and may be a printed circuit board assembly (PCBA). The aerosol generating device 10 may also include a user interface (not shown) for controlling the operation of the aerosol generating device 10 via the controller 20. The controller 20 may be configured to detect the initiation of use of the aerosol generating device 10, for example, in response to a user input, such as a button press to activate the aerosol generating device 10, or in response to a detected airflow through the aerosol generating device 10. As will be understood by one of ordinary skill in the art, an airflow through the aerosol generating device 10 is indicative of a user inhalation or ‘puff. The aerosol generating device 10 may, for example, include a puff detector (not shown), such as an airflow sensor or microphone, to detect an airflow through the aerosol generating device 10.

The heating chamber 16 has a first end 24 and a second end 26, and includes an opening at the first end 24 for receiving an aerosol generating substrate 30. In some examples (not illustrated), the second end 26 of the heating chamber 16 may be a closed end such that the heating chamber 16 forms a cup shape. The heating chamber 16 is positioned towards the proximal end 12 of the aerosol generating device 10. The heating chamber 16 defines a cavity for receiving the aerosol generating substrate 30. In use, an aerosol generating substrate 30 is positioned in the heating chamber 16 by a user through the open end. After use, the aerosol generating substrate 30 can be removed from the heating chamber 16 by a user and discarded. Thus, the aerosol generating substrate 30 is a consumable item which may, for example, contain tobacco as the aerosol generating substrate material.

The aerosol generating substrate 30 is substantially planar and has first and second planar surfaces. For example, the aerosol generating substrate 30 may be a flat-shaped substrate having a flat cuboid shape. Accordingly, the heating chamber 16 is dimensioned to receive an aerosol generating substrate 16 having a flat cuboid shape. Thus, the heating chamber 16 may form a cuboid shape, similar to the substantially planar aerosol generating substrate 30 and may be rectangular when viewed in crosssection. When the aerosol generating substrate 30 is inserted into the heating chamber 16, the aerosol generating substrate 30 remains flat-shaped. The aerosol generating substrate 30 can have any suitable flat shape and/or external dimensions, but because of its flat shape the effective thickness is much smaller than the other dimensions. In some examples, the aerosol generating substrate 30 may have a thickness, i.e., a dimension between the first and second planar surfaces, of between 1 mm and 5 mm. A preferred thickness may be in the range from 1 mm to 3 mm, and possibly in the range from 1 mm to 2 mm.

The aerosol generating device 10 includes a mouthpiece portion 38 at the proximal end 12. The mouthpiece portion 38 is positioned downstream of the heating chamber 16 in an aerosol flow direction through the aerosol generating device 10. The mouthpiece portion 38 is slidable in a direction substantially orthogonal to the longitudinal axis of the aerosol generating device 10 between a closed position (Figure 1) and an open position (Figure 3). The mouthpiece portion 38 can be biased to the closed position in some embodiments. The mouthpiece portion 38 includes an outlet 40 having a substantially rectangular cross-section as best seen in Figure 2. When the mouthpiece portion 38 is in the open position shown in Figure 3, the heating chamber 16 can be accessed and a user can insert an aerosol generating substrate 30 into the cavity through the open end. When the mouthpiece portion 38 is in the closed position shown in Figures 1 and 2, an inserted aerosol generating substrate 30 is retained in the cavity by the mouthpiece portion 38 because the cross-section of the outlet 40 is smaller than the cross-section of the cavity and, more particularly, is smaller than the cross-section of the aerosol generating substrate 30. Accordingly, the aerosol generating substrate 30 is too large to pass through the outlet 40.

It will be understood by one of ordinary skill in the art that a slidable mouthpiece portion 38 is not essential. For example, the mouthpiece portion 38 could be movable from the closed position to the open position by rotation, or by a combination of rotation and translation. Alternatively, the mouthpiece portion 38 could be detachable from the proximal end 12 of the aerosol generating device 10 to permit access to the cavity of the heating chamber 30.

The aerosol generating device 10 is an electrically-operated aerosol generating device 10 and, in the illustrated example, includes a first planar heater 34 and a second planar heater 36. In use, an aerosol generating substrate 30 is positioned in the heating chamber 16 between the first planar heater 34 and the second planar heater 36. More specifically, the aerosol generating substrate 30 is inserted by a user into the cavity 32 between the first planar heater 34 and the second planar heater 36.

In preferred embodiments, the aerosol generating device 10 generates heat using electrical resistive heating. In an example of a preferred embodiment, each planar heater 34, 36 comprises a rectangular ceramic plate with an electrical heating element (not shown) embedded inside the ceramic plate. The electrical heating elements have a high electrical resistance and generate heat in response to an electric current flow. The ceramic plates, which may contact the aerosol generating substrate 30 during use, conduct heat from the heating elements and transfer the heat to the aerosol generating substrate 30 primarily by conduction. Alternatively, the first and second planar heaters 34, 36 may be other types of heater, such as non-ceramic metal heating plates. The air in the cavity may also be heated.

Upon activation of the aerosol generating device 10 by a user, an electric current is supplied to the planar heaters 34, 36 causing them to heat up. The heat from the planar heaters 34, 46 is transferred to the adjacent aerosol generating substrate 30. This results in heating of the aerosol generating substrate 30 and a vapour is thereby generated. The generated vapour may cool and condense to form an aerosol for inhalation by a user of the aerosol generating device 10 through the mouthpiece portion 38. The vaporisation of the aerosol generating substrate 30 is facilitated by the addition of air from the surrounding environment, for example through the opening of the heating chamber 16.

Although two planar heaters 34, 46 are shown in the illustrated example, a single planar heater 34, 36 could be provided to heat the aerosol generating substrate 30. In another example in which the heating chamber 16 forms a cup shape as described above and may, for example, comprise a metal cup, a heater may be wrapped around the metal cup. In this example, the heater may be a thin film heater, for example a polyimide film heater. The cup-shaped heating chamber 16 typically forms a cuboid shape (having a rectangular or square cross-sectional shape) extending along the longitudinal axis of the aerosol generating device 10, complementary to the shape of the substantially planar aerosol generating substrate 30. In other examples, the cup-shaped heating chamber 16 may have a generally cylindrical cross-sectional shape and may be configured to receive an aerosol generating substrate 30 having a generally cylindrical cross-sectional shape. A thin-film heater can be conveniently wrapped around the cup-shaped heating chamber 16 irrespective of its cross-sectional shape. The aerosol generating device 10 further comprises a vapour chamber 42 having a first end region 44 and a second end region 46. In the illustrated example, two vapour chambers 42 are shown, but a single vapour chamber 42 could be provided.

The vapour chamber 42 is typically an ultra-thin vapour chamber and may be rectangular as illustrated. By “ultra-thin”, it is meant that the vapour chamber 42 has a thickness up to 1.0 mm, and more typically up to 0.5 mm. The vapour chamber 42 is partially filled with a liquid, e.g., water, which acts as a working fluid. The liquid absorbs heat from the proximal end 12 of the aerosol generating device 10 and is thereby heated and vaporised at the first end region 44 of the vapour chamber 42 during use of the aerosol generating device 10. Thus, the liquid in the vapour chamber 42 evaporates at the first end region 44 to form a vapour as it absorbs heat from the proximal end 12 of the aerosol generating device 10, creating a vapour pressure difference between the first end region 44 and the second end region 46. This vapour pressure difference causes a transfer of vapour from the first end region 44 to the second end region 46 of the vapour chamber 42. The heat is transferred from the vapour at the second end region, e.g., to the casing 23 of the aerosol generating device 10, and as the vapour cools due to this transfer of heat, it condenses back into a liquid. The liquid then flows back to the first end region 44 of the vapour chamber 42 so that it can again absorb heat from the proximal end 12 of the aerosol generating device 10. Thus, it will be understood that the vapour chamber 42 acts as a thermal energy transfer component and provides an effective and highly efficient way to transfer heat away from the proximal end 12 of the aerosol generating device 10, thus maintaining an acceptable temperature at the proximal end 12 so that a user can comfortably engage the proximal end 12, and in particular the mouthpiece portion 38, with their lips to inhale generated aerosol.

The vapour chamber 42 can be regarded as substantially planar and extends in a direction substantially parallel to the longitudinal axis of the aerosol generating device 10. The first end region 44 includes a substantially planar first contact surface 48 and the second end region 46 includes a substantially planar second contact surface 50. In the illustrated example, the first end region 44 of the vapour chamber 42 is positioned adjacent to the mouthpiece portion 38, and more particularly such that the substantially planar first contact surface 48 contacts a substantially planar surface of the mouthpiece portion 38. The second end region 46 of the vapour chamber 42 is positioned away from the mouthpiece portion 38, and more particularly such that the substantially planar second contact surface 50 contacts the inner surface 23a of the casing 23. This allows heat to be transferred efficiently by the vapour chamber 42 from the mouthpiece portion 38 to the casing 23 during use of the aerosol generating device 10.

In the illustrated example, the substantially planar first contact surface 48 and the substantially planar second contact surface 50 are not coplanar. More specifically, and as best seen in Figure 4, the substantially planar first contact surface 48 lies in a first plane and the substantially planar second contact surface 50 lies in a second plane that is offset from, and substantially parallel to, the first plane. This may help to ensure that an optimal contact can be achieved between the substantially planar first contact surface 48 and the substantially planar surface of the mouthpiece portion 38 and between the substantially planar second contact surface 50 and the inner surface 23a of the casing 23.

In an alternative example of an aerosol generating device as illustrated in Figures 5 and 6, the first end region 44 of the vapour chamber 42 is positioned adjacent to an outer surface (which may be substantially planar) of the heating chamber 16, and more particularly such that the substantially planar first contact surface 48 contacts the outer surface of the heating chamber 16. The second end region 46 of the vapour chamber 42 is positioned away from the heating chamber 16, and more particularly such that the substantially planar second contact surface 50 contacts the inner surface 23a of the casing 23. This allows heat to be transferred efficiently by the vapour chamber 42 from the heating chamber 16 to the casing 23 during use of the aerosol generating device 10, thereby reducing unwanted heat transfer from the heating chamber 16 to the mouthpiece portion 28.

The substantially planar first contact surface 48 and the substantially planar second contact surface 50 are again not coplanar in the example of Figures 5 and 6. More specifically, and as best seen in Figure 6, the substantially planar first contact surface 48 lies in a first plane and the substantially planar second contact surface 50 lies in a second plane that is offset from, and substantially parallel to, the first plane. This may help to ensure that an optimal contact can be achieved between the substantially planar first contact surface 48 and the outer surface of the heating chamber 16 and between the substantially planar second contact surface 50 and the inner surface 23a of the casing 23.

Although exemplary embodiments have been described in the preceding paragraphs, it should be understood that various modifications may be made to those embodiments without departing from the scope of the appended claims. Thus, the breadth and scope of the claims should not be limited to the above-described exemplary embodiments.

Any combination of the above-described features in all possible variations thereof is encompassed by the present disclosure unless otherwise indicated herein or otherwise clearly contradicted by context.

Unless the context clearly requires otherwise, throughout the description and the claims, the words “comprise”, “comprising”, and the like, are to be construed in an inclusive as opposed to an exclusive or exhaustive sense; that is to say, in the sense of “including, but not limited to”.

Claims

1. An aerosol generating device (10) having a proximal end (12), a distal end (14) and a longitudinal axis extending between the proximal end (12) and the distal end (14), the aerosol generating device (10) comprising: a heating chamber (16) positioned towards the proximal end (12) for receiving an aerosol generating substrate (30); and a vapour chamber (42) containing a working fluid, the vapour chamber (42) having first and second end regions (44, 46) and being arranged to transfer heat from the first end region (44) to the second end region (46) by evaporation of the working fluid inside the vapour chamber (42) at the first end region (44) and condensation of the working fluid inside the vapour chamber (42) at the second end region (46), the first end region (44) being positioned at or adjacent to the proximal end (12) of the aerosol generating device (10) and the second end region (46) being positioned away from the proximal end (12).

2. An aerosol generating device according to claim 1, wherein the vapour chamber (42) is substantially planar and extends in a direction substantially parallel to the longitudinal axis of the aerosol generating device (10).

3. An aerosol generating device according to claim 1 or claim 2, wherein the first end region (44) includes a substantially planar first contact surface (48) in contact with a substantially planar surface of a first component (16, 38) of the aerosol generating device (10) at or adjacent to the proximal end (12) of the aerosol generating device (10).

4. An aerosol generating device according to any preceding claim, wherein the second end region (46) includes a substantially planar second contact surface (50) in contact with a substantially planar surface (23a) of a second component (23) of the aerosol generating device (10) at a position away from the proximal end (12) of the aerosol generating device (10).

5. An aerosol generating device according to claim 3 and claim 4, wherein the substantially planar first contact surface (48) and the substantially planar second contact surface (50) are coplanar.

6. An aerosol generating device according to claim 3 and claim 4, wherein the substantially planar first contact surface (48) lies in a first plane and the substantially planar second contact surface (50) lies in a second plane offset from, and substantially parallel to, the first plane.

7. An aerosol generating device according to any preceding claim, wherein the first end region (44) of the vapour chamber (42) is positioned adjacent to an outer surface of the heating chamber (16) and the second end region (46) of the vapour chamber (42) is positioned away from the heating chamber (16) to transfer heat away from the heating chamber (16).

8. An aerosol generating device according to claim 7, wherein the first end region (44) of the vapour chamber (42) contacts the outer surface of the heating chamber (16).

9. An aerosol generating device according to any preceding claim, wherein the aerosol generating device (10) includes a mouthpiece portion (38) at the proximal end (12), the first end region (44) of the vapour chamber (42) is positioned adjacent to the mouthpiece portion (38) and the second end region (46) of the vapour chamber (42) is positioned away from the mouthpiece portion (38) to transfer heat away from the mouthpiece portion (38).

10. An aerosol generating device according to claim 9, wherein the first end region (44) of the vapour chamber (42) contacts a surface of the mouthpiece portion (38).

11. An aerosol generating device according to claim 9 or claim 10, wherein the mouthpiece portion (38) is positioned downstream of the heating chamber (16) in an aerosol flow direction through the aerosol generating device (10).

12. An aerosol generating device according to any preceding claim, wherein the heating chamber (16) includes a planar heater (34, 36) that is configured to heat a substantially planar aerosol generating substrate (30).

13. An aerosol generating device according to any preceding claim, wherein the aerosol generating device includes a casing (23) having an inner surface (23a) and an outer surface (23b), and the second end region (46) of the vapour chamber (42) contacts the inner surface (23a) of the casing (23).

14. An aerosol generating device according to claim 13, wherein the casing (23) comprises a metal, preferably aluminium.