WO2022189360A1

WO2022189360A1 - Heater module

Info

Publication number: WO2022189360A1
Application number: PCT/EP2022/055756
Authority: WO
Inventors: Menno Bijlsma; Ernst Hupkes
Original assignee: Jt International Sa
Priority date: 2021-03-09
Filing date: 2022-03-07
Publication date: 2022-09-15

Abstract

A heating module (1) for an aerosol generation device (100), the heating module comprising a heating chamber (10) configured to receive and heat an aerosol substrate, a rigid support (40) surrounding the heating chamber, and a first thermal insulation layer (20) surrounding the rigid support.

Description

HEATER MODULE

Field of Invention

The present disclosure relates to a heater arrangement, in particular a heater arrangement for an aerosol generation device. The disclosure is particularly applicable to a portable aerosol generation device, which may be self-contained and low temperature. Such devices may heat, rather than burn, tobacco or other suitable aerosol substrate materials by conduction, convection, and/or radiation, to generate an aerosol for inhalation. Background

The popularity and use of reduced-risk or modified-risk devices (also known as vaporisers) has grown rapidly in the past few years as an aid to assist habitual smokers wishing to quit smoking traditional tobacco products such as cigarettes, cigars, cigarillos, and rolling tobacco. Various devices and systems are available that heat aerosolisable substances to release a vapour for inhalation, rather than relying on burning of tobacco.

A commonly available reduced-risk or modified-risk device is the heated substrate aerosol generation device or heat-not-burn device. Devices of this type generate an aerosol or vapour by heating an aerosol substrate that typically comprises moist leaf tobacco or other suitable aerosolisable material to a temperature typically in the range 150°C to 300°C. Heating an aerosol substrate, but not combusting or burning it, releases an aerosol that comprises the components sought by the user but not the toxic and carcinogenic by-products of combustion and burning. Furthermore, the aerosol produced by heating the tobacco or other aersolisable material does not typically comprise the burnt or bitter taste resulting from combustion and burning that can be unpleasant for the user and so the substrate does not therefore require the sugars and other additives that are typically added to such materials to make the smoke and/or vapour more palatable for the user. Known aerosol generating devices typically include a heating chamber for receiving a consumable aerosol generating substrate, a power source and control circuitry for controlling the supply of power to the heating chamber from the power source.

One known issues with such devices is that the inevitable proximity of the heating chamber to the power source and control circuitry within the device can cause unwanted heating of the power source and electronic circuitry. This heating may damage these heat-sensitive electronic components and, in some cases, this may even be dangerous with a risk of fire or explosion when components that are not designed to be heated become too hot.

It is an object of the present invention to address the above mentioned issues and provide an aerosol generating device in which heat management is improved whilst still providing a compact, user-friendly device.

Summary of Invention

According to a first aspect there is provided a heating module for an aerosol generation device, the heating module comprising a heating chamber configured to receive and heat an aerosol substrate, a rigid support surrounding the heating chamber, and a first thermal insulation layer surrounding a surface of the rigid support.

The rigid support may provide the function of holding or retaining the thermal insulation layer in place around the heating chamber. The insulation arrangement may improve insulation efficiency and may provide an even and decreased temperature at the surface of the rigid support. This may reduce the chance of heat sensitive components becoming too hot.

In some examples, a first thermal insulation layer is surrounded by a surface of the rigid support. The rigid support comprises at least one through hole, preferably a plurality of through holes. The through-holes are preferably distributed evenly in the rigid support. The through holes are preferably provided in a tubular wall of the rigid support. The thermal insulation may cause the temperature of the rigid support to be relatively high due to residual conduction of heat from the heating chamber to the rigid support. The through-holes may act as air pockets within the rigid support, reducing the conduction of heat from the heating chamber to the rigid support. The through-holes may reduce the thermal mass of the rigid support helping reduce the temperature of the rigid support. The air pockets may also ensure thermal insulation of the heating chamber, providing a more efficient thermal insulation arrangement.

The through-holes may minimize surface contact between the heating chamber and the rigid support to reduce the temperature of the rigid support, whilst maintaining a rigid support for holding the thermal insulation in place around the heating chamber.

In some developments, a first end of the through hole may be covered by the first thermal insulation layer. Closing, or blocking one end of the through-holes may reduce air circulation to the surface of the rigid support which may reduce the chance of localized areas becoming hot. As such, the temperature of the rigid support may be substantially even across the surface of the rigid support.

The at least one through hole may have a number of different shapes including a circular, oblong or polygonal cross-section. The through-holes may all have the same shape.

The rigid support may comprise a regular pattern of through holes. Regularly spaced through-holes may help provide an even surface temperature of the rigid support.

The thickness of the rigid support may be between 0.4 mm and 0.6 mm, and preferably may be about 0.5 mm. Preferably the rigid support may comprise a thermally insulating material, more preferably, the rigid support may be made of PEEK. This may improve the insulation properties of the rigid support.

In some examples, the first thermal insulation layer may comprise a flexible wrap. The first thermal insulation layer may comprise a ceramic fiber, preferably wherein the ceramic fiber is a thermal alkaline earth silicate (AES) fiber such as Superwool^®. The fiber is preferably formed as a blanket or paper. In some examples, the ceramic fiber may comprise one or more of the following: aluminium oxide, silicon oxide (Si02), magnesium oxide (MgO), calcium oxide (CaO), zirconium oxide (Zr02).

Preferably, the heating module may further comprise a heat diffusion layer arranged to surround the first thermal insulation layer. Preferably, the heat diffusion layer comprises graphite. The heat diffusion layer may act as a diffuser or heat reflector to help spread out the heat and reduce the chance of hotspots being created. This may help to lower the overall temperature of the heating module. The heat diffusion layer may be arranged to surround the first thermal insulation layer. The heat diffusion layer may additionally or alternatively be arranged to surround the rigid support.

Some exemplary heating modules may further comprise a second thermal insulation layer arranged to surround the first thermal insulation layer. The second thermal insulation layer may also surround the heat diffusion layer. A second thermal insulation layer may help improve the insulation of the heating chamber.

The second thermal insulation layer may be made of the same or different material to that of the first thermal insulation layer. The second thermal insulation layer may have a thickness that is the same or different to the thickness of the first thermal insulation layer.

In some examples, the heat diffusion layer may be arranged between the first and second thermal insulation layers. In this way, the heat diffusion layer may act to separate adjacent layers of thermal insulation. The heat diffusion layer may help diffuse heat between the adjacent layers of thermal insulation, which may improve thermal insulation of the heating chamber and reduce the overall temperature of the heating module.

In some developments, the heating module may further comprise a second heat diffusion layer arranged to surround the second thermal insulation layer. The second diffusion layer may act as a diffuser or heat reflector to help spread out the heat and reduce the chance of hotspots being created, helping to lower the overall temperature of the heating module.

The second diffusion layer may be made of the same or different material to that of the first diffusion layer. The second diffusion layer may have a thickness that is the same or different to the thickness of the first diffusion layer.

Preferably, a second end of the at least one through hole is covered by the first diffusion layer. In this case, both the first and second ends of the through-holes may be covered. Due to the closure of the through holes by the insulation layer and the diffusion layer, there is reduced air circulation to the surface of the rigid support and so there is a reduced chance of local hotspots forming. This helps ensure that the temperature at the surface of the rigid support is even and relatively low.

In some cases, the heating module may comprise a spacer element arranged to define an air gap between the heating chamber and the rigid support. An air layer may be defined by the combination of the through-holes and the air gap. The air gap may reduce the chance of heat conduction between the heating chamber and the rigid support, which may help reduce the overall temperature of the rigid support whilst maintaining good insulation of the heating chamber.

Preferably, the spacer element may comprise end portions arranged to enclose ends of the air gap between the heating chamber and the rigid support. The enclosed air gap may serve the purpose of reducing turbulence, and so reducing conduction through moving air, which may help prevent heat transfer from the heating chamber to the rigid support. The air gap may serve to reduce thermal mass of the heating module. In some examples, the rigid support may comprise two half portions configured to engage with each other to surround the heating chamber. Having two separate portions may help ensure that the heating chamber is correctly located within the rigid support during assembly and facilitates the assembling of the device, in particular with the spacer element.

The two half portions may comprise complementarily-shaped press-fitting connections configured to hold the two half portions together in a predefined assembling position. The two half portions may alternatively or additionally be glued using an adhesive or be welded such as by ultrasounds.

The first diffusion layer may be configured to surround the two half portions of the rigid support. The first diffusion layer may be configured to be tightly wrapped around the two half portions of the rigid support. This may allow the first diffusion layer to hold the two half portions of the rigid support together. This may provide a convenient mechanism of holding the two portions of the rigid support together, without the need for additional components.

In some examples, the rigid support may comprise a single component for example a frame. This may reduce the number of parts that need to be assembled to form the heater module, which may reduce manufacturing costs.

The heating chamber of the heating module may comprise a thermally conductive cup and a heating element arranged outside the thermally conductive cup.

The rigid support may circumferentially surround the heating chamber so as to define an air gap between the longitudinal surface of the heating chamber and the rigid support.

An insulating layer, for example the first thermal insulation layer, may be arranged around an exterior surface of the rigid support. In this arrangement, the air gap may exist between the heating chamber and the insulating layer which surrounds it. It has been found that the when the air gap, rigid support, and insulating layer are arranged in this way, a higher level of insulation is achieved than can be attained by a layer of insulating material with an equivalent thickness (i.e. the summed thickness of the air gap, rigid support, and insulating layer) being applied directly to the surface of the heating chamber. This arrangement therefore achieves improved insulation and thus enables the provision of aerosol generating devices with superior heat management and more compact construction to those known previously. A further advantage of the arrangement is that it requires less insulating material than a device in which the insulating material is applied directly to the surface of the heating chamber, and therefore achieves a construction that is more economical and lightweight.

Preferably, the air gap extends across at least 50%, preferably at least 90%, more preferably substantially 100%, of the longitudinal surface of the heating chamber. The greater the area of the longitudinal surface that is covered by the air gap (and thus not in contact with features such as the rigid support), the less heat is conducted from the longitudinal surface away from the heating chamber, which further reduces the risk of heating the other components of a device in which the heater assembly is incorporated. For the same reasons, the rigid support is preferably not in contact with the longitudinal surface of the heating chamber.

According to another aspect there may be provided an aerosol generating device as described above.

The heating module may provide a low cost, light weight and easy to assemble means to insulate a heating chamber within an aerosol generating device.

According to another aspect there may be provided a heater assembly for an aerosol generating device, the heater assembly comprising: a heating chamber comprising a cavity adapted to receive, in use, an aerosol generating substrate, and a longitudinal surface that extends along a longitudinal axis and which encloses the cavity; a tubular support structure which extends along the longitudinal axis and which circumferentially surrounds the heating chamber so as to define an air gap between the longitudinal surface of the heating chamber and the tubular support structure; and an insulating layer arranged around an exterior surface of the tubular support structure. In this arrangement, air gap exists between the heating chamber and the insulating layer which surrounds it. It has been found that the when the air gap, support structure and insulating layer are arranged in this way, a higher level of insulation is achieved than can be attained by a layer of insulating material with an equivalent thickness (i.e. the summed thickness of the air gap, support structure and insulating layer of the device) being applied directly to the surface of the heating chamber. The device therefore achieves improved insulation and thus enables the provision of aerosol generating devices with superior heat management and more compact construction to those known previously. A further advantage of the device is that it requires less insulating material than a device in which the insulating material is applied directly to the surface of the heating chamber, and therefore achieves a construction that is more economical and lightweight.

In some preferred embodiments, the tubular support structure comprises two semi-cylindrical sections connected to one another along a longitudinal interface that extends substantially along the longitudinal axis. The heater assembly can be assembled by placing the heating chamber between the two semi-cylindrical sections of the support structure and then bringing the two semi-cylindrical section together to join at the interface. Alternatively, in other preferred embodiments, the tubular support structure may comprise an integral tubular section that extends continuously around the heating chamber. In this case, the heating chamber can be inserted through one end of the tubular support structure for assembly.

Preferably a plurality of openings extend through a surface of the tubular support structure. Depending on the arrangement of the openings, the tubular support structure could have a mesh or frame-like structure defined by the openings, for example. Providing openings in the tubular support structure reduces the conduction of heat from the air gap to the ends of the heater assembly by the support structure and therefore improves the level of insulation provided by the support structure. Advantageously, at least some of the plurality of openings are spaced from one another along the longitudinal axis. This enhances the insulating effect of the openings. Preferably the plurality of openings are each circular or hexagonal. These shapes are particularly suitable as they do not substantially diminish the strength of the tubular support structure. In preferred embodiments, the plurality of openings are arranged in a regular array. This achieves the best insulation and mechanical strength. For example, hexagonal openings could be arranged in a regular array so as to define a hexagonal mesh structure.

Advantageously, the heater assembly may comprise one or more graphite layers each disposed on a surface of the tubular support structure and/or the insulating layer.

Preferably the heater assembly comprises a support member arranged to interface with a first end portion of the heating chamber and in contact with the tubular support structure so as to space the tubular support structure from the longitudinal surface of the heating chamber. The end portions of a heating chamber (which is typically cylindrical in shape and hence has two end portions), which constitute its extremities, are typically cooler than the other parts of the chamber when in use. By arranging the support member to interface with an end portion of the heating chamber, rather than a more central part, the rate of heat transfer from the heating chamber to the support structure and other parts of the device is minimised. This in turn improves the level of insulation achieved by the heater assembly as a whole. The support member also ensures that the tubular support structure is resiliently spaced from the heating chamber so as to define the air gap without coming into contact with the longitudinal surface of the heating chamber. This ensures that the air gap remains in place but does not substantially reduce the degree of insulation achieved by the support structure and insulator because it does not contact the longitudinal surface of the heater assembly. The support member preferably extends partially or wholly around the circumference of the heating chamber. In this way, the support member may provide a secure mechanical connection to support the rigid support structure. The support member may comprise a body extending around most or all of the circumference of an end of the heating chamber and one or more longitudinal struts arranged periodically around the body, which extend along the length of the heating chamber. In this way the length tolerances of the tubular support assembly and heating chamber are improved, aiding the manufacturing process. Preferably, the support member and tubular support structure are configured to mechanically connect to one another such that the support member supports the tubular support structure. The support member may also be configured to engage with a frame within an aerosol generating device whereby the heater assembly can be mounted in position within the aerosol generating device. In some preferred embodiments, a second such support member may be provided at a second end portion of the tubular support structure.

The heater assembly preferably further comprises an insulating ring arranged at a second end portion of the heating chamber. The support structure may be attached to this insulating ring so that, similar to the support member described above, the tubular support structure is resiliently spaced from the heating chamber at its second end. The insulating ring may be arranged to allow access to the cavity via the second end of the heating chamber. Hence, in particularly preferred embodiments, the second end portion of the heating chamber comprises an inlet for receiving, in use, the aerosol generating substrate.

In preferred embodiments the tubular support structure comprises a heat-resistant material, preferably polyether ether ketone (PEEK). The use of a heat-resistant material ensures that high temperatures inside the air gap do not compromise the mechanical integrity of the support structure. PEEK is a particularly suitable material due to its high mechanical strength, which is retained at high temperatures.

Preferably the insulating layer comprises aerogel and/or a fibre-based insulating material, preferably a ceramic fibre material, for example a metal oxide fibre material such as Superwool^® or a ceramic fibre sheet comprising one or more of aluminium oxide, silicon oxide and Zr02. One example of such a material is a Superwool^® blanket. These materials have excellent insulating properties which allow a high level of insulation to be achieved by a comparatively thin layer of insulating material, which allows the heater assembly to be made particularly compact.

Advantageously, the air gap extends across at least 50%, preferably at least 90%, more preferably substantially 100%, of the longitudinal surface of the heating chamber. The greater the area of the longitudinal surface that is covered by the air gap (and thus not in contact with features such as the tubular support structure), the less heat is conducted from the longitudinal surface away from the heating chamber, which further reduces the risk of heating the other components of a device in which the heater assembly is incorporated. For the same reasons, the tubular support structure is preferably not in contact with the longitudinal surface of the heating chamber.

There may also be provided an aerosol generating device comprising a heater assembly as defined above. The aerosol generating device may comprise other components including a power source, for example a battery, and electronics for controlling the supply of power to the heating chamber.

As will be understood, any of the above described features forming part of above described aspects or preferred embodiments may be combined with any or all features forming part of above described aspects or preferred features.

Brief Description of Drawings

Embodiments of the present invention will now be described by way of example only with reference to the accompanying drawings in which:

Figure 1 is a schematic view of a heater arrangement for an aerosol generating device;

Figures 2A and 2B are schematic views of an aerosol generating device;

Figures 3A to 3C are schematic views of a heater arrangement for an aerosol generating device;

Figures 4A to 4F are schematic views of a heater arrangement for an aerosol generating device;

Figures 5A and 5B are schematic views of a heater arrangement for an aerosol generating device; Figures 6A to 6C are schematic views of a heater arrangement for an aerosol generating device;

Figures 7A to 7E are schematic views of a heater arrangement for an aerosol generating device; Figures 8A and 8B are schematic views of a heater arrangement for an aerosol generating device;

Figure 9 shows the components of an exemplary tubular support structure;

Figure 10 shows an example of a heater assembly in a disassembled state;

Figure 11 shows a cutaway view of the heater assembly of Figure 10; Figure 12 shows a cross-sectional view of the heater assembly of Figures 10 and 11 ;

Figure 13 shows an example of an aerosol generating device comprising the heater assembly of Figures 10 to 12;

Figure 14 shows the components of another exemplary tubular support structure; Figure 15 shows an example of a heater assembly in a disassembled state;

Figure 16 is a cutaway view of the heater assembly of Figure 15;

Figure 17 is a cross-sectional view of the heater assembly of Figures 15 and 16; and

Figure 18 shows an example of an aerosol generating device comprising the heater assembly of Figures 15 to 18.

Detailed Description

Figure 1 schematically illustrate a heater module 1 for an aerosol generating device 100 such as that pictured in Figures 2A and 2B. The heater module 1 includes a tubular heating chamber 10 comprising a cavity 11 arranged to receive and heat an aerosol generating substrate. The tubular heating chamber preferably comprises a heat conductive cup and a heater, e.g. a “thin film heater”, on the outer or inner surface of the chamber. In an embodiment, the tubular heating chamber 10 is wrapped with a layer of thermal insulation 20, shown in Figures 5A and 8A, so as to circumferentially surround the heating chamber 10. The heating module 1 further includes a support assembly 30 including a rigid support 40 arranged to around the heating chamber 10, as shown in Figures 3A and 6A. The thermal insulation layer 20 is arranged to surround a surface of the rigid support 30, as shown in Figures 5A and 8A.

The insulation support assembly 30 is arranged to engage the heating chamber 10 and the thermal insulation layer 20 so as to hold the thermal insulation layer 20 in position around the heating chamber 10, as will be described in further detail later.

Unlike known devices which commonly use vacuum tubes as insulators for the heater chamber 10, the heater module 1 described herein allows improved thermal insulation performance. The heater module 1 is also lower cost compared to vacuum tubes, easier to assemble and is low weight further increasing the ease of assembly and support within the device, while providing a lighter and more user friendly device to the user.

As shown in Figure 3B and 6B the insulation support assembly 30 is a multicomponent assembly comprising a rigid surround 40, the details of which will be described later. In the example of Figure 1, the heating chamber 10 is heated by a thin film heater 12 which is wrapped circumferentially around an outer surface of the heating chamber 10. Generally, the layer of insulation 20 surrounds the heating chamber 10 and thin film heater 12 to restrict the passage of heat out of the rigid support 40 to the other external components of the device.

In the example of Figures 3B and 6B the insulation support assembly 30 also includes heating chamber supports 50. The heating chamber supports 50 generally take the form of annular or partially annular supports which engage with the ends 13, 14 of the tubular heating chamber 10 as shown generally in Figure 1. The heating chamber supports 50 also engage with the rigid support 40, such that they hold the heating chamber 10 in position within the rigid support 40, as shown in Figures 3C and 6C. The supports 50 also ensure a defined gap is maintained between the heating chamber and the heating chamber support. This defined gap may at least be partially filled with air. As explained further below, the heater chamber supports 50 contact only the longitudinal ends 13, 14 of the heating chamber 10 which are the coolest points on the heating chamber 10 so as to minimise the transport of heat from the heating chamber 10 to the rigid support 40 and the connecting components of the aerosol generating device 100.

The assembled heater module 1 may then be mounted within an exemplary aerosol generating device as shown in Figure 2Aand 2B. Although in this example the heater and battery are axially aligned, in other examples the heater and battery may be located next to each other and may optionally include control circuitry in between. The heater module 1 may be held within a housing 101 of the aerosol generating device 100 by a heater assembly frame 110. The heater chamber supports 50 are configured to connect with connection features on the heater chamber frame 110 such that the heater module 1 is supported within the housing 101 of the device 100 by the engagement between the heater supports 50 of the insulation support assembly 30 and the frame 110. In this way, the thermal connection points between the heating chamber 10 and the remaining internal components of the device 100 and the housing 101 are minimised. In particular, since the chamber supports 50 only contact the heating chamber 10 at the longitudinal ends, the coolest points, and further because the contacts between the heating chamber supports 50 and the frame 110 and rigid support 40 are minimised, the spread of heat to the remaining components of the device is significantly restricted.

The insulation support assembly 30 including the rigid support 40 and the heater chamber supports 50 are preferably made of a rigid and heat stable material, which may be a thermally insulating material. In particular, the material must remain rigid upon heating to temperatures of up to around 300°C.The material is preferably a heat resistant polymer material, such as PEEK. The rigid support 40 may have a thickness of 1 mm, but generally has a thickness of between 0.4 mm and 0.6 mm, and preferably the thickness is about 0.5 mm.

The thermal insulation layer 20 is preferably in the form of a sheet which is wound circumferentially around the heating chamber 10 for at least one turn, preferably multiple turns, in order to further improve the thermal insulation. The thermal insulation layer 20 may therefore be thought of as comprising a flexible wrap. Different materials may be selected for the thermal insulation layer 20. The examples include aerogels or a ceramic fibre material i.e. a metal oxide fibre material. For example a ceramic fibre sheet comprising aluminium oxide, silicon oxide (Si02), magnesium oxide (MgO), calcium oxide (CaO) and/or zirconium oxide (Zr02). One example of such a material is a thermal alkaline earth silicate (AES) such as Superwool^® blanket or paper. The thermal insulation layer 20 has a thickness of about 0.5 mm to 1.5 mm, preferably 0.8 mm to 1.2 mm, and in some cases about 1 mm.

The rigid support 40 is configured to support the layer of thermal insulating material 20 in position around the heating chamber 10. The insulation support assembly 30 includes a base heating chamber support 51 which is shaped so as to provide an opening for connections from the heater 12 to pass to the control circuitry and battery.

This general principle of the invention therefore provides a lightweight assembly 30 surrounding the heating chamber 10 in order to securely hold the thermal insulation layer 20 in position around the heater 12 and the heating chamber 10, whilst only maintaining minimal contact with the heating chamber 10, preferably just at the end points and therefore provides a cheap, lightweight and easy to assemble alternative to a vacuum tube for application in aerosol generating devices 1. Within this general concept, the heater arrangement 1 may be implemented in a number of different ways. Certain exemplary arrangements in which the invention may be implemented will now be described in detail, with reference to Figures 3-5 illustrating a first example and Figures 6-8 illustrating a second example. The individual components of the following examples may be exchanged between the examples and the features of various embodiments can be combined within the above broad principle of the invention.

In a first example, illustrated in Figure 3A, the rigid support 40 takes the form of a two-part tubular housing comprising two semi-cylindrical housing portions 41 , 42 which connect around the heating chamber 10 along a longitudinal interface to form a rigid cylindrical support 40 which holds the thermal insulating layer 20 in position around the heating chamber 10.

The first component of the insulation support assembly 30 is the base heating chamber support 51 which is sleeved over the base end 14 of the heating chamber 10 and over the thin film heater 12, as shown in Figure 4A. The first heating chamber support 51 comprises an annular body 53 which extends at least partially around the circumference of the base end 14 of the heating chamber 10 and further comprises a number of axial struts 52 which extend partially along the length of the heating chamber 10 from the annular body 53. In this way, the struts 52 engage with the end 14 of the heating chamber 10 and provide the support which allows it to be mounted securely within the surround 40.

As shown in Figure 4B the struts 52 extend over the thin film heater 12 to securely grip the thin film heater 12 and the heating chamber 10. In some cases, the film heater 12 can be fixed to the metal wall of the heating chamber by heat shrink film such as Polyimide, PTFE, PEEK, etc. The layer of thermal insulation 20, in the form of a sheet of thermally insulating material, is then wrapped circumferentially around the heating chamber 10, the thin film heater 12 and struts 52 of the first heating chamber support 51 as shown in Figure 4C. The assembled heating chamber 10 and thermal insulating layer 20 are then positioned in the first semi- cylindrical portion 42 of the rigid support 40, as shown in Figure 4C.

As shown in Figure 4D the second heating chamber support 52 is then connected to the open end 13 of the heating chamber 10 and engages the open end of the semi-cylindrical portions 41 , 42 of the rigid surround 40. Turning to Figure 4E, the second portion 41 of the cylindrical housing 40 is then clipped into position to form the complete rigid support 40 around the thermal insulation layer 20 and tubular heating chamber 10 to provide the heater module 1 as shown in Figure 4F. Mechanical connection portions 43 at the base of the rigid support 40, together with the second heating chamber support 52 allow for connection of the assembled heater module 1 into the aerosol generating device 100.

Looking generally at the examples in Figures 3A-3C, the heating chamber 10 is generally cylindrical in shape and has a longitudinal surface 203 that extends along the longitudinal axis X. The two semi-cylindrical portions 41 , 42 are brought together such that that heating chamber 10 and first heating chamber support 51 are disposed inside the volume enclosed by the assembled rigid support 40. The first heating chamber support 51 is shaped such that it resiliently engages the interior surfaces of the semi-cylindrical portions 41 , 42, and the heating chamber is supported by the strut 52, which extends along the longitudinal axis X when the device is in the assembled state. The heating chamber 10 has a diameter that is less than that of the interior space defined by the connected semi-cylindrical portions 41 , 42, so the heating chamber 10 is supported in such a way that the longitudinal surface 203 is not in contact with the rigid support 40. As a result, an air gap exists between the longitudinal surface 203 and the rigid support 40.

In a second example, illustrated in Figure 6A, the arrangement utilises the same core concept in the use of an insulation support assembly 30 including a rigid support 40 which acts to hold the thermal insulation layer 20 in position around the heating chamber 10. However, rather than the rigid support 40 being positioned outside of the thermal insulation layer 20 so as to hold the thermal insulation layer 20 at an outer surface of the thermal insulation layer 20 (as with the first example and illustrated in Figure 5A), in this example the rigid support 40 comprises a frame 45 which supports the insulation layer 20 from below, against a (radially) inner surface of the thermal insulation layer 20 as illustrated in Figure 8A. In particular, the frame 45 provides a supporting surface around which the insulation surface 20 is wrapped. In both the first and second examples, the thermal insulation layer 20 can be said to surround a surface of the rigid support 40. In the first example, the thermal insulation layer 20 can be thought of as surrounding an inner surface of the rigid support 40, as shown in Figure 5A. In the second example, the thermal insulation layer 20 can be thought of as surrounding an outer surface of the rigid support 40, as shown in Figure 8A.

Turning back towards the second example, the rigid support 40 is in the form of a tubular frame 45 which is sleeved around the tubular heating chamber 10, as shown in Figure 7A. The tubular heating chamber 10 is inserted into the frame 45 such that the heating chamber 10 is surrounded by the frame 45.

The frame 45 providing the rigid support 40 comprises two end rings 46a, 46b. The end ring 46a at the open end of the chamber may be configured to engage with the heating chamber 10 to secure it in position. In this example, the base end ring 46b, shown in Figure 7B, of the support frame 45 takes the place of the first heating chamber support 51 in the first example. In particular, the frame 45 extends beyond the base end 14 of the heating chamber 10 and it may be used in a similar way to connect the frame 45 within the aerosol generating device 100, using a connection feature 43.

With the tubular heating chamber 10 and thin film heater 12 held by the mechanical connection of the frame 45 and heating chamber support 52, the sheet of thermal insulating material 20 is then wrapped around the outer surface of the frame 45 as shown in Figure 7C and 7D.

Looking generally at the example in Figures 6A-6C and 7A-7E, the rigid support 40 and the heating chamber supports 50 are shaped such that when assembled, the longitudinal surface 203 of the heating chamber 10 is not in contact with the rigid support 40 or any other part of the heater assembly. The diameter of the heating chamber 10 is less than the interior diameter of the rigid support 40, so an air gap is formed between the longitudinal surface 203 and the insulating material in the assembled heater assembly. As with the previously described examples, the heater arrangement 1 , shown in Figure 7E, comprises a sheet of thermally insulating material 20 held by an insulation support assembly 30 which engages with the heating chamber 10 and holds the insulation layer 20 in position around the heating chamber 10. The assembled heater module 1 may then be connected into an aerosol generating device 100, such as that pictured in Figure 2A and 2B.

The heater modules 1 described above further include a heat diffusion layer 60 arranged to surround the thermal insulation layer 20, as shown in Figures 5A and 5B. In the first example shown in Figure 5A, the heat diffusion layer 60 is arranged on an outer surface of the rigid support 40. In this case, the heat diffusion layer 60 can be thought of as indirectly surrounding the thermal insulation layer 20 and directly surrounding the rigid support 40. In this example, the heat diffusion layer 60 acts to hold the two semi-cylindrical housing portions 41 , 42 of the rigid support 40 together. For this, the thermal insulation layer 20 may comprise an adhesive layer such silicone glue. In the second example shown in Figure 8A, the heat diffusion layer 60 is arranged on an outer surface of the thermal insulation layer 20. In this case, the heat diffusion layer 60 can be thought of as directly surrounding the thermal insulation layer 20 and indirectly surrounding the rigid support 40.

The heat diffusion layer 60 acts as a diffuser to spread out heat from hotspots which may form in the thermal insulation layer 20 or the rigid support 40, helping to lower the temperature. The heat diffusion layer 60 is made of any suitable heat reflective material such as graphite. The layer of graphite is preferably thinner than the thermal insulation layer 20 as well as thinner than the rigid support 40.

In some example heater modules 1 there is a second thermal insulation layer 70 arranged to circumferentially surround the thermal insulation layer 20, which may be referred to as a first thermal insulation layer 20. As illustrated in Figures 5B and 8B, the second thermal insulation layer 70 also surrounds the heat diffusion layer 60. In other words, the heat diffusion layer 60 is arranged between the first thermal insulation layer 20 and the second thermal insulation layer 60. In some examples, the second thermal insulation layer 70 can be considered as being directly applied to the heat diffusion layer 60 and so the heat diffusion layer 60 is associated with the second thermal insulation layer 70.

In one example shown in Figure 5B, the second thermal insulation layer 70 may be made of a thinner layer of ceramic fibre material, preferably comprising aluminium oxide, silicon oxide (Si02), magnesium oxide (MgO), calcium oxide (CaO) and/or zirconium oxide (Zr02), such as a Superwool™ blanket and the like. In one example shown in Figure 8B, a second thermal insulation layer 70 may be made of ceramic fibre material and may have the same thickness as the first thermal insulation layer 20.

Typically, the second insulation layer 60 has a thickness of about 0.5 mm to 1.5 mm, preferably 0.8 mm to 1.2 mm, and in some cases about 1 mm.

When multiple layers of insulation are wrapped over the rigid support 40, a heat diffusion layer 60 is positioned between adjacent layers of insulation wrap 20, 70, as illustrated in Figure 8A.

A second diffusion layer 80 can be applied to the second thermal insulation layer 70 such that the second diffusion layer 80 circumferentially surrounds the second thermal insulation layer 70, as shown in Figures 5B and 8B.

As before, the second diffusion layer 80 acts as a diffuser to spread out heat from hotspots which may form in the second thermal insulation layer 70, helping to lower the temperature of the heater module 1. The second diffusion layer 80 is made of any suitable heat reflective material such as graphite. The first and second diffusion layers 60, 80 may be made of the same or different materials.

Looking again the structure of the rigid support 40, the surface of the rigid support 40 comprises a plurality of through-holes 47, as can be seen in Figures 3A and 6A. The surface of the rigid support 40 is susceptible to accumulate heat and this is minimized due to the presence of the through-holes 47. The through-holes 47 therefore act to reduce the thermal mass of the rigid support 40, helping to reduce the overall temperature of the rigid support 40. The plurality of through-holes 47 are evenly distributed across the surface of the tubular wall of the rigid support 40, helping to reduce the temperature of the rigid support 40 evenly across the structure of the rigid support 40. The through-holes 47 may have any suitable shape, including a circular, oblong, hexagonal or polygonal cross-section, which is able to reduce thermal mass and prevent air from circulating and causing turbulence. Preferably, the through-holes 47 covers a surface of at least 30%, more preferably at least 40% of the overall surface of the tubular wall including the through holes. The number of through holes 47 may vary depending on the axial and circumferential dimensions of the rigid support 40 and surface area of the through holes 47. In particular, the number of through holes 47 may vary from 40 to 200, more preferably between 50 and 120. The number of through-holes 47 and surface area is determined to maintain a sufficient rigidity of the structure while achieving the reduction of heat on the surface.

Each through hole has an inner end 48 on the internal surface of the rigid support 40 and an outer end 49 on the external surface of the rigid support 40, as shown in Figures 3B and 6B.

In the examples shown in Figures 3-5, the inner end 48 of the through-holes 47 is covered by the first thermal insulation layer 20. The outer end 49 of the through- holes 47 is covered by the first diffusion layer 60. Thus, in this arrangement, both ends of each through-hole 47 are blocked or covered, preventing air from escaping. Due to the closure of the through-holes 47 by the thermal insulation layer 20 and the diffusion layer 60, there is no air circulation to the surfaces of the rigid support 40. Reducing air circulation is important because circulating air may cause turbulence and may result in local areas of higher temperature across the rigid support 40. The enclosed through-holes 47 therefore ensure that the temperature across the surface of the rigid support 40 is even and relatively low.

In the example shown in Figures 6-8, the outer end 49 of the through-holes 47 is covered by the first diffusion layer 60. However, in this case, the inner end 48 of the through-holes is uncovered, as can be seen in Figures 8A and 8B. As described previously with reference to Figures 7A and 7B, the rigid support 40 comprises two end rings 46a, 46b. The end rings 46a, 46b act as a spacer element such that the rigid support 40 is supported so as to leave a gap 75 between the rigid support 40 and the surface of the heating chamber 10, as shown in Figures 8A and 8B. The end rings 46a, 46b therefore define the air gap 75 between the heating chamber 10 and the rigid support 40. The air gap may have a thickness of around 1 mm, and may preferably be around 0.5 to 0.8 mm, and in some cases may be about 0.6 mm.

The two end rings 46a, 46b include end portions which are shaped to enclose the ends of the air gap 75 between the heating chamber 10 and the rigid support 40, forming a substantially sealed space.

The sealed space forms an air layer between the rigid support 40 and the heating chamber 10, and includes the air gap 75 and the air pockets created by the through-holes 47. As before, the air layer acts to reduce turbulence, which reduces conduction of heat by moving air from the heating chamber 10 to the rigid support 40. The air layer therefore helps reduce the thermal mass of the module 1 and reduces the surface temperature of the rigid support 40.

In the examples described above, the through-holes 47 in the rigid support 40 reduce the conduction of heat from the air gap 75 to the ends of the heater assembly by the rigid support 40 and therefore improve the level of insulation provided by the rigid support 40.

As has been described, the heater assembly comprises at least one heating chamber support 50 arranged to interface with an end portion of the heating chamber 10 and in contact with the rigid support 40 so as to space the rigid support 40 from the longitudinal surface 203 of the heating chamber 10. The end portions of a heating chamber 10 (which is typically cylindrical in shape and hence has two end portions), which constitute its extremities, are typically cooler than the other parts of the heating chamber 10 when in use. By arranging the heating chamber support 50 to interface with an end portion of the heating chamber 10, rather than a more central part, the rate of heat transfer from the heating chamber 10 to the rigid support 40 and other parts of the device is minimised. This in turn improves the level of insulation achieved by the heater assembly as a whole. The heating chamber support 50 also ensures that the rigid support 40 is resiliently spaced from the heating chamber 10 so as to define the air gap 75 without coming into contact with the longitudinal surface 203 of the heating chamber 10. This ensures that the air gap 75 remains in place but does not substantially reduce the degree of insulation achieved by the rigid support 40 and insulator because it does not contact the longitudinal surface of the heater assembly.

A number of additional features and modifications may be applied to the above examples. For example, the thermal insulation may be in the form of a sheet which is wrapped once or multiple times about the heating chamber. The insulation support assembly 30 may be assembled by mechanical connection and/or guiding elements such as pin/holes, press fitting, ultrasonic welding, inorganic adhesive, screws or magnets for example. To further secure the rigid support 40 in place, the rigid support 40 can be externally covered by an adhesive supporting layer such as a graphite layer with an adhesive layer. The rigid surround may also be internally coated with a metal heat reflective layer or metal foil which could in some examples be wound together with a super insulation layer to further enhance the heat management properties of the device.

In the following, some other examples of components of a heater assembly will be described. It is to be understood that any or all of these components may be combined with any or all the components described above in relation to the above described heater module as appropriate.

Figure 9 shows examples of components of a heater assembly. A first semi- cylindrical section 101a and a second semi-cylindrical section 101b of a tubular support structure are shown. Each semi-cylindrical section 101a, 101b has a curved surface through which a plurality of openings 103 extend. In this example, the openings 103 are circular and are arranged in accordance with a regular array that extends across the surface of the tubular support structure. Each semi- cylindrical section 101a, 101b has a respective open end 105a, 105b and a respective closed end 107a, 107b. When the two semi-cylindrical sections 101a, 101b are joined together, they form a tubular support structure which extends along a longitudinal axis X.

The components include a support member 111. The support member 111 has a body 113, which, as will be shown later, cooperates with the ends of the semi- cylindrical sections 101a, 101b. The support member 111 also has a longitudinal strut 109 and a flange 117 which each extend from the body 113 and are shaped to support a heating chamber in the assembled heater assembly. Although in this example a single longitudinal strut 109 is shown, other embodiments may be provided with a plurality of such struts 109 arranged periodically (e.g. regularly spaced in a circumferential manner) around the body 113.

The sections 101a, 101 b of the tubular support structure may be each be provided with a receiving feature that is adapted to receive the flange 117, for example a groove or recess. This improves the connection between the support member 111 and the tubular support structure and thereby improves the structural rigidity of the support structure. The flange 117 may be omitted in some embodiments, since the longitudinal strut 109 is independently capable of supporting the heating chamber. However, the provision of a flange 117 is preferred because of the additional support that this feature provides to the heating chamber and because it improves the connection of the support member 111 to the tubular support structure.

The components also include an insulating ring 115 which is shaped to cooperate with the opens ends 105a, 105b of the semi-cylindrical sections. In the assembled tubular support structure, the insulting ring 115 thus forms an open end of the tubular support structure via which the heating chamber can be accessed.

All of the components shown in Figure 9 are preferably made of a heat resistant material such as polyether-ether ketone (PEEK).

Figure 10 shows the components of Figure 9 and a heating chamber 201 arranged prior to assembly. The heating chamber 201 is generally cylindrical in shape and has a longitudinal surface 203 that extends along the longitudinal axis X. To assemble the heater assembly from this state, the protruding feature 109 of the support member 111 is first brought into engagement with an end of the heating chamber 201. Then, the two semi-cylindrical sections 101a, 101b, are brought together such that that heating chamber 201 and support member 111 are disposed inside the volume enclosed by the now-assembled tubular support structure. The body 113 is shaped such that it resiliently engages the interior surfaces of the semi-cylindrical sections 101a, 101b, and the heating chamber is supported by the longitudinal strut 109, which extends along the longitudinal axis X when the device is in the assembled state. The heating chamber 201 has a diameter that is less than that of the interior space defined by the connected semi- cylindrical sections 101a, 101b, so the heating chamber 201 is supported in such a way that the longitudinal surface 203 is not in contact with the tubular support structure. As a result, an air gap exists between the longitudinal surface 203 and the tubular support structure. Next, the insulating ring 115 is connected to the open end 105 of the tubular support structure (which is formed by the open ends 105a, 105b of the semi-cylindrical sections 101a, 101b). Finally, an insulating layer 121 (shown in Figure 12) is applied circumferentially around the curved surface of the tubular support structure. As noted above, preferred materials suitable for the insulating layer 121 are aerogels or a ceramic fibre material, for example a metal oxide fibre material such as Superwool^® or a ceramic fibre sheet comprising one or more of aluminium oxide, silicon oxide and ZrC>2. One example of such a material is a Superwool^® blanket.

Figure 11 shows a cutaway view of the assembled heater assembly 301, in which the first semi-cylindrical section 101a has been removed so that the interior can be seen.

Figure 12 shows schematically a cross-sectional view of the heater assembly 301 of Figure 11. In addition to the components shown in the preceding Figures, this view shows an insulating layer 121 which is arranged around the exterior surface of the support structure, in this case directly on the exterior of the first and second semi-cylindrical sections 101a, 101b. Preferred materials for forming the insulating layer 121 include aerogel and fibre-based insulating materials, e.g. Superwool^®.

Figure 13 shows an example of an aerosol generating device 501 comprising the heater assembly 301 of Figure 11. In this aerosol generating device 501, the heater assembly 301 is arranged so that the heating chamber 201 is accessible via the open end 105 of the support structure for the insertion and removal of the substrate to be heated. In addition to the heater assembly 301, the aerosol generating device 501 may include features such as a power source for supplying power to the heating chamber 201 , a temperature sensor for sensing the temperature of parts of the device (e.g. inside the heating chamber 201 or in the surrounding parts of the device) and an electrical controller for controlling the heating chamber 201 and other features of the device.

Figure 14 shows components of a second example of a heater assembly. The tubular support structure comprises an integral tubular section 601, the interior of which is accessible via a first end 605a and a second end 605b. Similar to the previous example, a plurality of openings 603 extend through the surface of the integral tubular section 601. These openings 603 are arranged in accordance with a regular array that extends across the surface of the support structure. The heater assembly also comprises a support member 611 , which, as will be shown later, is adapted to engage the integral tubular section 601 at the first end 605a and to support a heating chamber arranged inside the tubular section 601. In this example, the support member 611 does not have a longitudinal strut of the kind described previously, but does incorporate a flange 617, which extends longitudinally from the body 613 of the support member and provides support to the heating chamber in the assembled state. Similar to the previous example, the tubular section 601 may be provided with a receiving feature such as a recess or groove that is adapted to receive the flange 617. This improve the connection between the tubular section 601 and the support member 611.

The heater assembly also includes an insulating ring 615, which is similar to the insulating ring 115 of the previous example and is adapted to fit onto the second end 607 of the integral tubular section 601. Like in the previous example, this insulting ring provides access to the interior of the heating chamber for insertion and removal of substrates, e.g. heated tobacco products. All of the components shown in Figure 14 are preferably made of a heat resistant material such as polyether-ether ketone (PEEK).

The heater assembly is assembled as shown in Figure 15. A heating chamber 701 of the kind described previously is inserted into the integral cylindrical section 601 via either end and brought into engagement with the support member 611 , which itself engages the second end 605b of the cylindrical section 601. The cylindrical section 601 and the support member 611 are shaped such that when assembled in this manner, the longitudinal surface 703 of the heating chamber 701 is not in contact with the cylindrical section 601 or any other part of the heater assembly. The insulating ring 615 is then fixed to the second end 607 of the tubular section 601. Similarly to the previous example, after these components have been assembled, an insulating layer is applied around the tubular section 601. The diameter of the heating chamber 701 is less than the interior diameter of the tubular section 601, so an air gap is formed between the longitudinal surface 703 and the insulating layer in the assembled heater assembly.

Figure 16 is a cutaway view of the heater assembly 801 in the assembled state, omitting the insulating layer for clarity. In this view, the air gap between the longitudinal surface 703 of the heating chamber 701 and the tubular section 601 is clearly visible.

Figure 17 is a cross-sectional view of the assembled heater assembly 801 , including an insulating layer 621 which is wound around the exterior of the tubular section 601. As in the previous example, aerogel and ceramic fibre materials such as Superwool are examples of suitable insulating materials for this layer. This example also has a graphite layer 623 which is applied on the exterior surface of the insulating layer 621. The graphite layer 623 may be attached by an adhesive layer. The graphite layer 623 is not essential, however.

Figure 18 shows an example of an aerosol generating device 1001 comprising the heater assembly 801 of Figure 16. In this aerosol generating device 1001 , the heater assembly 801 is arranged so that the heating chamber 701 is accessible via the first end 605 of the support structure for the insertion and removal of the substrate to be heated. In addition to the heater assembly 801, the aerosol generating device 1001 may include features such as a power source for supplying power to the heating chamber 701 , a temperature sensor for sensing the temperature of parts of the device (e.g. inside the heating chamber 701 or in the surrounding parts of the device) and an electrical controller for controlling the heating chamber 701 and other features of the device. Definitions and Alternative Embodiments

As will be noted from above, when describing a first set of examples a first set of terminology is used and when describing a second set of examples a second set of terminology is used. However, it will be appreciated that whilst different terminology may have been used, it will be understood by the skilled person that features that perform the same or similar function in one set of examples correspond to features that perform the same or similar function in another set of examples, despite any difference in terminology or reference numerals. As such, features in one set of examples which perform one set of functions may be interchangeable with features in another set of examples which perform the same set of functions.

For example, the heater assembly of one example may correspond to the heater module of another example. The tubular support structure of one example may correspond to the rigid support of another example. The through-holes 47 of one example may correspond to the openings 103 of another example. The first thermal insulation layer 20 in one example may correspond to the insulating layer 121 of another example. The two semi-cylindrical sections 101b 101a in one example may correspond to the two semi-cylindrical housing portions 41 , 42 in another example. The integral tubular section 601 in one example may correspond to an insulation support assembly 30 in another example. It will be appreciated that other correspondences may exist that have not been explicitly mentioned here. These will be apparent to the skilled person based on the drawings and the associated description.

It will be appreciated from the description above that many features of the described embodiment perform independent functions with independent benefits. Therefore the inclusion or omission of each of these independent features from embodiments of the invention defined in the claims can be independently chosen.

The term “heater” should be understood to mean any device for outputting thermal energy sufficient to form an aerosol from the aerosol substrate. The transfer of heat energy from the heater to the aerosol substrate may be conductive, convective, radiative or any combination of these means. As non-limiting examples, conductive heaters may directly contact and press the aerosol substrate, or they may contact a separate component such as the heating chamber which itself causes heating of the aerosol substrate by conduction, convection, and/or radiation.

Heaters may be electrically powered, powered by combustion, or by any other suitable means. Electrically powered heaters may include resistive track elements (optionally including insulating packaging), induction heating systems (e.g. including an electromagnet and high frequency oscillator), etc. The heater may be arranged around the outside of the aerosol substrate, it may penetrate partway or fully into the aerosol substrate, or any combination of these. For example, instead of the heater of the above-described embodiment, an aerosol generation device may have a blade-type heater that extends into an aerosol substrate in the heating chamber.

Aerosol substrate includes tobacco, for example in dried or cured form, in some cases with additional ingredients for flavouring or producing a smoother or otherwise more pleasurable experience. In some examples, the aerosol substrate such as tobacco may be treated with a vaporising agent. The vaporising agent may improve the generation of vapour from the aerosol substrate. The vaporising agent may include, for example, a polyol such as glycerol, or a glycol such as propylene glycol. In some cases, the aerosol substrate may contain no tobacco, or even no nicotine, but instead may contain naturally or artificially derived ingredients for flavouring, volatilisation, improving smoothness, and/or providing other pleasurable effects. The aerosol substrate may be provided as a solid or paste type material in shredded, pelletised, powdered, granulated, strip or sheet form, optionally a combination of these. Equally, the aerosol substrate may be a liquid or gel. Indeed, some examples may include both solid and liquid/gel parts.

Consequently, the aerosol generating device 1 could equally be referred to as a “heated tobacco device”, a “heat-not-burn tobacco device”, a “device for vaporising tobacco products”, and the like, with this being interpreted as a device suitable for achieving these effects. The features disclosed herein are equally applicable to devices which are designed to vaporise any aerosol substrate.

The aerosol generation device may be arranged to receive the aerosol substrate in a pre-packaged substrate carrier. The substrate carrier may broadly resemble a cigarette, having a tubular region with an aerosol substrate arranged in a suitable manner. Filters, vapour collection regions, cooling regions, and other structure may also be included in some designs. An outer layer of paper or other flexible planar material such as foil may also be provided, for example to hold the aerosol substrate in place, to further the resemblance of a cigarette, etc. The substrate carrier may fit within the heating chamber or may be longer than the heating chamber such that the lid remains open while the aerosol generation device 1 is provided with the substrate carrier. In such embodiments, the aerosol may be provided directly from the substrate carrier which acts as a mouthpiece for the aerosol generation device.

As used herein, the term “aerosol” shall mean a system of particles dispersed in the air or in a gas, such as mist, fog, or smoke. Accordingly the term “aerosolise” means to make into an aerosol and/or to disperse as an aerosol. Note that the meaning of aerosol/aerosolise is consistent with each of volatilise, atomise and vaporise. For the avoidance of doubt, aerosol is used to consistently describe mists or droplets comprising atomised, volatilised or vaporised particles. Aerosol also includes mists or droplets comprising any combination of atomised, volatilised or vaporised particles.

Implementation 1 : A heater assembly for an aerosol generating device, the heater assembly comprising: a heating chamber comprising a cavity adapted to receive, in use, an aerosol generating substrate, and a longitudinal surface that extends along a longitudinal axis and which encloses the cavity; a tubular support structure which extends along the longitudinal axis and which circumferentially surrounds the heating chamber so as to define an air gap between the longitudinal surface of the heating chamber and the tubular support structure; and an insulating layer arranged around an exterior surface of the tubular support structure.

Implementation 2: The heating assembly of implementation 1, wherein the tubular support structure comprises two semi-cylindrical sections connected to one another along a longitudinal interface that extends substantially along the longitudinal axis.

Implementation 3: The heating assembly of implementation 1, wherein the tubular support structure comprises an integral tubular section that extends continuously around the heating chamber.

Implementation 4: The heater assembly of any preceding implementation, wherein a plurality of openings extend through a surface of the tubular support structure.

Implementation 5: The heat assembly of implementation 4, wherein at least some of the plurality of openings are spaced from one another along the longitudinal axis.

Implementation 6: The heater assembly of implementation 4 or implementation 5, wherein the plurality of openings are each circular or hexagonal.

Implementation 7: The heater assembly of any of implementations 4 to 6, wherein the plurality of openings are arranged in a regular array. Implementation 8: The heater assembly of any preceding implementation, further comprising one or more graphite layers each disposed on a surface of the tubular support structure and/or the insulating layer.

Implementation 9: The heater assembly of any preceding implementation, further comprising a support member arranged to interface with a first end portion of the heating chamber and in contact with the tubular support structure so as to space the tubular support structure from the longitudinal surface of the heating chamber.

Implementation 10: The heater assembly of any preceding implementation, further comprising an insulating ring arranged at a second end portion of the heating chamber.

Implementation 11 : The heater assembly of implementation 10, wherein the second end portion of the heating chamber comprises an inlet for receiving, in use, the aerosol generating substrate.

Implementation 12: The heater assembly of any preceding implementation, wherein the tubular support structure comprises a heat-resistant material, preferably polyether ether ketone (PEEK).

Implementation 13: The heater assembly of any preceding implementation, wherein the insulating layer comprises aerogel and/or a fibre-based insulating material, preferably a ceramic fibre material, most preferably Superwool.

Implementation 14: The heater assembly of any preceding implementation, wherein the air gap extends across at least 50%, preferably at least 90%, more preferably substantially 100%, of the longitudinal surface of the heating chamber.

Implementation 15: The heater assembly of any preceding implementation, wherein the tubular support structure is not in contact with the longitudinal surface of the heating chamber.

Claims

1. A heating module for an aerosol generation device, the heating module comprising: a heating chamber configured to receive and heat an aerosol substrate; a rigid support surrounding the heating chamber; and a first thermal insulation layer surrounding a surface of the rigid support or a first thermal insulation layer is surrounded by a surface of the rigid support; and wherein the rigid support comprises at least one through hole, preferably a plurality of through-holes.

2. The heating module according to claim 1 , wherein a first end of the at least one through hole is, and preferably a first end of each of the plurality of the through holes are, covered by the first thermal insulation layer.

3. The heating module according to claim 1or 2, wherein the at least one through hole has, or each of the plurality of through holes have, a circular, oblong or polygonal cross-section.

4. The heating module according to any preceding claim, wherein the rigid support has a thickness of between 0.4 mm and 0.6 mm, preferably wherein the thickness is about 0.5 mm.

5. The heating module according to any preceding claim, wherein the rigid support comprises a thermally insulating material.

6. The heating module according to any preceding claim, wherein the first thermal insulation layer comprises a flexible wrap.

7. The heating module according to any preceding claim wherein the first thermal insulation layer comprises a ceramic fiber, preferably wherein the ceramic fiber comprises aluminium oxide, silicon oxide (Si02), magnesium oxide (MgO), calcium oxide (CaO) and/or zirconium oxide (Zr02).

8. The heating module according to claim 2, further comprising a heat diffusion layer arranged to surround the first thermal insulation layer, wherein the heat diffusion layer preferably comprises graphite.

9. The heating module according to claim 8, further comprising a second thermal insulation layer arranged to surround the first thermal insulation layer.

10. The heating module according to claim 9, further comprising a second heat diffusion layer arranged to surround the second thermal insulation layer.

11. The heating module according to any of claims 8 to 10, wherein a second end of the at least one through hole is covered by the first diffusion layer.

12. The heating module according to any of claims 1 to 11 , further comprising a spacer element arranged to define an air gap between the heating chamber and the rigid support.

13. The heating module according to claim 12, wherein the spacer element comprises end portions arranged to enclose ends of the air gap between the heating chamber and the rigid support.

14. The heating module according to any of claims 1 to 13, wherein the rigid support comprises two half portions configured to engage with each other to surround the heating chamber.

15. The heating module according to any of claims 1 to 14, wherein the ridig support circumferentially surrounds the heating chamber so as to define an air gap between the longitudinal surface of the heating chamber and the tubular support structure and the air gap preferably extends across at least 50%, preferably at least 90%, more preferably substantially 100%, of the longitudinal surface of the heating chamber.