An aerosol generating device

Abstract

An aerosol generating device (2) is described. The aerosol generating device (2) includes an energy storage device (e.g., a rechargeable battery) and an inner assembly (4) with a heating chamber (6) adapted to receive an aerosol generating article (100), a heater (8) adapted to heat the aerosol generating article (100) when received in the heating chamber (6), and a printed circuit board assembly (10) with a printed circuit board (12) and one or more electronic components adapted to control operation of the aerosol generating device (2). An outer housing of the aerosol generating device (2) substantially surrounds the inner assembly (4) and the energy storage device. The outer housing (18) includes a first outer sleeve made of a non-metallic first material having a first thermal conductivity. A wireless charging assembly (24) of the aerosol generating device (2) is arranged between an inner surface of the first outer sleeve and the inner assembly (4). The wireless charging assembly (24) includes a receiving coil (26) for wireless inductive charging, and a planar substrate (28) having a first main surface (28a) facing the inner surface of the first outer sleeve (20), and a second main surface opposite the first main surface (28a). The receiving coil (26) is embedded in the substrate (28) or mounted to the first main surface (28a) of the substrate (28). The aerosol generating device (2) also includes one or more thermally conductive elements connected to at least a part of the second main surface of the planar substrate (28) and arranged between the wireless charging assembly (24) and the inner assembly (4). The one or more thermally conductive elements are in thermal contact with the inner assembly (4) to provide a thermal bridge between the wireless charging assembly (24) and the inner assembly (4).

Description

[0001] AN AEROSOL GENERATING DEVICE

[0002] Technical Field

[0003] The present disclosure relates generally to an aerosol generating device, and in particular to a device that is adapted to heat aerosol generating material to generate an aerosol for inhalation by a user. A wireless charging assembly of the aerosol generating device may be used for wireless charging of an energy storage device, e.g., a rechargeable battery.

[0004] The present disclosure is particularly applicable to a portable (hand-held) aerosol generating device.

[0005] Technical Background

[0006] Devices which heat, rather than bum, an aerosol generating material to produce an aerosol for inhalation have become popular with consumers in recent years. A commonly available reduced-risk or modified-risk device is the heated material aerosol generating device, or so-called heat-not-bum device. Devices of this type generate an aerosol or vapour by heating an aerosol generating material to a temperature typically in the range 150°C to 300°C, and in some cases as high as 350°C. This temperature range is quite low compared to an ordinary cigarette. Heating the aerosol generating material to a temperature within this range, without burning or combusting the aerosol generating material, generates a vapour which typically cools and condenses to form an aerosol for inhalation by a user of the device.

[0007] The aerosol generating material may be a solid or liquid. For example, the aerosol generating article may include a solid or semi-solid substrate of plant derived material, such as tobacco, or it may include a wick and a heater to produce vapour from aerosol generating liquid stored in a capsule or tank. A stick that looks like an ordinary cigarette may also be used as an aerosol generating article. When a user operates the aerosol generating device, liquid that has soaked into the wick is heated by the heater, producing a vapour which cools and condenses to form an aerosol

[0008] P51801WO-6617 which may then be inhaled. An aerosol generating article (sometimes called a pod or cartridge) may be received in the aerosol generating device and may include a liquid store, a liquid transfer element (e.g., a wick) and a heater. Electrical contacts may provide an electrical connection between the heater and an energy storage device of the aerosol generating device. The energy storage device may be a rechargeable battery that may be charged from an external power source by a charging assembly of the energy storage device assembly.

[0009] The charging assembly may include an inductive receiving coil suitable for wireless charging of the battery. In particular, a wireless external power source such as a wireless charger will include an inductive transmitting coil that creates an electromagnetic field when an electric current flows through it. The inductive transmitting coil and the inductive receiving coil may also be referred to as a primary coil and a secondary coil, respectively. When the receiving coil of the charging assembly of the aerosol generating device is in close proximity with the wireless charger, the electromagnetic field generates an electric current in the receiving coil of the charging assembly that may be provided to a charging circuit and used to charge the battery. Wireless charging is a convenient way to charge the battery without having to physically and / or mechanically connect a charging cable to the aerosol generating device. New ingress protection standards may also mean that wired charging assemblies, e.g., those that might include a plug socket such as a universal serial bus (USB) socket (receptacle) for receiving a USB charging cable (plug), and which therefore also require an opening in the housing, may no longer be suitable for use in aerosol generating devices. Using wireless charging may also avoid the need for a user to carry or use a separate charging cable.

[0010] An aerosol generating device that uses wireless charging typically has more internal components (e.g., the wireless charging assembly) than an aerosol generating device that is not compatible with wireless charging. An aerosol generating device is typically a portable (hand-held) device so its size and weight may be limited. It may therefore be difficult to accommodate these additional internal components within the housing of the aerosol generating device. The lack of internal space within the

[0011] P51801WO-6617 housing may also make it more difficult to protect sensitive electronic components from the electromagnetic field generated during wireless charging.

[0012] There is a need for an improved aerosol generating device that overcomes the issues mentioned above, and where the aerosol generating device is designed specifically for wireless charging of a battery or other power source using a wireless charging assembly that is positioned within a housing of the aerosol generating device. In particular, there is a need for an improved aerosol generating device that has a mechanical structure that is suitable for wireless charging.

[0013] Summary of the Disclosure

[0014] According to a first aspect of the present disclosure, there is provided an aerosol generating device comprising: an inner assembly comprising: a heating chamber adapted to receive an aerosol generating article; a heater adapted to heat the aerosol generating article when received in the heating chamber; and a printed circuit board assembly (PCBA) comprising a printed circuit board (PCB) and one or more electronic components adapted to control operation of the aerosol generating device; an energy storage device (e.g., a rechargeable battery) adapted to supply power to the heater; an outer housing that substantially surrounds the inner assembly and the energy storage device, the outer housing comprising: a first outer sleeve comprising a non-metallic first material having a first thermal conductivity; a wireless charging assembly arranged between an inner surface of the first outer sleeve and the inner assembly, the wireless charging assembly comprising: a receiving coil for wireless inductive charging; and a planar substrate having a first main surface facing the inner surface of the first outer sleeve, and a second main surface opposite the first

[0015] P51801WO-6617 main surface, wherein the receiving coil is embedded in the substrate or mounted to the first main surface of the substrate; and one or more thermally conductive elements connected to at least a part of the second main surface of the substrate of the wireless charging assembly and arranged between the wireless charging assembly and the inner assembly, wherein the one or more thermally conductive elements are in contact with the inner assembly, e.g., in thermal contact to provide a thermal bridge between the wireless charging assembly and the inner assembly.

[0016] The aerosol generating device is designed to provide a heat flow path to transfer and dissipate heat generated by the wireless charging assembly, e.g., during wireless charging. The first outer sleeve at partially covers the receiving coil and is therefore made of a non-metallic first material because an electrically conductive material cannot be positioned between the receiving coil of the wireless charging assembly and the transmitting coil of the external wireless charger if a wireless connection between the receiving and transmitting coils is to be established. The first material may be a suitable plastics material, for example.

[0017] The thermally conductive elements may have a thermal conductivity that is greater than the first thermal conductivity, i.e., the thermal conductivity of the first outer sleeve.

[0018] Because the thermally conductive elements are in thermal contact with the inner assembly, heat generated by the wireless charging assembly during wireless charging, for example, is transferred to the inner assembly where it may be dissipated.

[0019] The substrate may be formed as a shielding member that may shield the internal components of the aerosol generating device from the electromagnetic field that is generated by an inductive transmitting coil of an external wireless charger, for example, during wireless charging. The substrate may be a ferrite sheet or a sheet of ferrite-containing material, for example. Alternatively, the receiving coil may be mounted on the first main surface of a non-shielding part of the substrate or embedded

[0020] P51801WO-6617 in the non-shielding part of the substrate, and the substrate may include a shielding part at the second main surface of the substrate. The shielding part may be a ferrite sheet or a sheet of ferrite-containing material, for example. It will be understood that ferrite is typically an iron-oxide containing magnetic ceramic material.

[0021] The outer housing may further comprise a second outer sleeve comprising a second material. The second material may have a second thermal conductivity which is greater than the first thermal conductivity. The inner assembly may be in contact (i.e. , thermal contact) with the second outer sleeve. This provides a heat flow path from the wireless charging assembly to the outside environment - i.e., from the receiving coil through the substrate and the thermally conductive elements to the inner assembly, and then from the inner assembly to the outside environment through the second outer sleeve. The inner assembly may comprise a support frame or body and the second outer sleeve may be in thermal contact with the support frame or body. The PCB may be mounted on the support frame or body, for example. The first outer sleeve may be arranged at a first end of the aerosol generating device, where it may at least partially cover the receiving coil, and the second outer sleeve may be arranged at a second end of the aerosol generating device, opposite the first end. The first end of the aerosol generating device may include an opening that allows the aerosol generating article to be inserted into the heating chamber. The energy storage device (e.g., the rechargeable battery or other power source) may be located at the second end of the aerosol generating device. The first and second outer sleeves may be arranged side- by-side and together may define an exterior of the aerosol generating device. The first and second outer sleeves may be connected together, e.g., along facing or interposing edges, or where part of the first or second outer sleeve overlaps with the other.

[0022] The inner assembly may further comprise a metallic member at least partially covering a component side of the PCB on which the one or more electronic components are mounted. The metallic member may be made of any suitable metal or metal alloy. The component side of the PCB may face the second main surface of the substrate, i.e., the main surface that faces the inner assembly and to which the one or more thermally conductive elements are connected. The metallic member is therefore

[0023] P51801WO-6617 positioned between the substrate and the component side of the PCB. At least part of one of the one or more thermally conductive elements may be in contact (i.e. , thermal contact) with at least a part of the metallic member. The metallic member may be mounted on the support frame or body of the inner assembly, for example.

[0024] The inner assembly may further comprise at least one heat sink arranged for dissipating heat generated by the PCBA, e.g., by the one or more electronic components. The at least one heat sink may be in contact (i.e., thermal contact) with at least a part of the one or more thermally conductive elements. The metallic member that covers the PCB may be a heat sink and a shielding member. A separate heat sink may also be provided. The heat sink may include a main part that is substantially planar and is in thermal contact with the support frame or body of the inner assembly. A tab part may be provided at an edge of the main part of the heat sink and may be thermal contact with the PCB. The heat sink may be designed to transfer heat from the PCB to the support frame or body of the inner assembly where it is dissipated or transferred to the outside environment through the second outer sleeve.

[0025] The one or more thermally conductive elements may comprise at least a thermally conductive elastomeric pad and / or a thermally conductive self-adhesive tape. For example, in a particular arrangement, the one or more thermally conductive elements may comprise one or more strips of thermally conductive self-adhesive tape that are optionally connected to the second main surface of the substrate and a separate heat sink, and one or more thermally conductive elastomeric pads that are optionally connected to the second main surface of the substrate and the metallic member. If the thermally conductive element is a self-adhesive tape, it may be used to physically connect or adhere the substrate to the inner assembly (e.g., to the heat sink and / or the metallic shield) as well as providing a thermal bridge between the two parts of the aerosol generating device. The one or more thermally conductive elements may be positioned so that they avoid contacting certain areas of the metallic member. For example, if a controller such as a microcontroller unit (MCU) is mounted on the PCB and is covered by the metallic member, it may be preferred that a thermally conductive element does not contact the area of the metallic member that covers the

[0026] P51801WO-6617 controller so that heat is not transferred to this area to prevent the controller from being damaged. This may apply to any electronic components that are heat-sensitive, for example. The part of the metallic member that covers the controller may be raised above the plane of the remainder of the metallic member, or may optionally be formed as a raised flap that covers the controller, for example. This may allow the thickness of the controller to be more easily accommodated.

[0027] A thickness of each of the one or more thermally conductive elements is preferably selected such that each thermally conductive element substantially spans a gap between the wireless charging assembly and the inner assembly, i.e., the space between the second main surface of the substrate and the facing surface of the inner assembly. It may be that the outer surface of the inner assembly is not flat and the thickness of each thermally conductive element may therefore be selected so that it is in thermal contact with both the substrate and the facing surface of the inner assembly - i.e., so that a thermal bridge between the wireless charging assembly and the inner assembly is established. The outer surface of the inner assembly may be defined by one or more of the support frame or body, the metallic member and the separate heat sink, for example. If a thermally conductive element is compressible or elastomeric, its uncompressed thickness may be slightly greater than the gap between the substrate and the facing surface of the inner assembly so that it is maintained in a compressed state. This may ensure a good thermal contact between the thermally conductive element and the other parts of the aerosol generating device.

[0028] The receiving coil may be in direct contact with the inner surface of the first outer sleeve. This minimises the distance between the receiving coil and the transmitting coil of external wireless charger during wireless charging, thereby improving charging efficiency.

[0029] The one or more thermally conductive elements may be a thermally conductive self- adhesive tape having a shape which is substantially completely overlapped with the second main surface of the planar substrate of the wireless charging assembly. For

[0030] P51801WO-6617 example, the strip of thermally conductive self-adhesive tape may be substantially the same size as, or larger than, the substrate.

[0031] The first outer sleeve may be formed by machining or by a moulding process, e.g., injection moulding. The first outer sleeve may comprise a suitable plastics material. The first outer sleeve may optionally comprise a metallic coating - e.g., a coating of a metal or metal alloy such as copper or nickel. The metallic coating of the first outer sleeve may be formed by electroplating, for example. The metallic coating may improve the thermal conductivity of the first outer sleeve, but will not normally extend on that part of the first outer sleeve that covers the receiving coil for the reasons described above.

[0032] The second outer sleeve may comprise a suitable metal or metal alloy, e.g., aluminium. The second outer sleeve may comprise a suitable plastics material with a metallic coating - e.g., a coating of a metal or metal alloy such as copper or nickel. The metallic coating of the second outer sleeve may be formed by electroplating, for example. The metallic coating may improve the thermal conductivity of the second outer sleeve if it is formed mainly of a plastics material. It will be understood that the thermal conductivity for a coated plastics material may be an effective (or overall) thermal conductivity, which may be considered as being a combination of the thermal conductivity of the separate materials - i.e., the plastics material and the metallic coating material. The thermal conductivity of the second outer sleeve as a whole may therefore be measured or determined.

[0033] We might need to define the thermal conductivity for the embodiment of a plastic with metal coatings. The thermal conductivity for the coated plastic will be an effective (or overall) thermal conductivity, which is considered as a combination of the two materials. The thermal conductivity of the metal-coated plastic can be measured when the component is considered as a whole.

[0034] The one or more electronic components of the PCBA may comprise a controller (e.g., a MCU that may be implemented as an integrated circuit (IC)). The controller may be

[0035] P51801WO-6617 mounted to the PCB and is adapted to control operation of the aerosol generating device. The PCBA may further comprise a connector adapted to electrically connect the wireless charging assembly to the PCBA. The connector may be mounted to the PCB, e.g., to the component side of the PCB, adjacent the controller to simplify the electrical circuit. The wireless charging assembly may comprise one or more wires that are used to electrically connect the receiving coil to the PCBA. The end of the one or more wires may comprise a connector that is compatible with the connector mounted to the PCB. For example, one of the connectors may be a male-type connector and the other may be a female-type connector that can be engaged together, i.e., the connectors are “plug-in” connectors. Using connectors may make it easier to assemble the aerosol generating device.

[0036] The one or more electronic components may include a wireless charging receiver circuit that may be implemented as an IC. The electric current generated in the receiving coil is an alternating current (AC) current. The wireless charging receiver circuit may be adapted to convert the AC current to a direct current (DC) current. The DC current may have an appropriate amplitude, e.g., an amplitude that is appropriate for charging the energy storage device, and this may be output by the wireless charging receiver circuit, or by a converter circuit that is electrically connected to the wireless charging receiver circuit and the energy storage device.

[0037] The optional metallic member may comprise an opening that corresponds to the position of the connector that is mounted to the PCB. The opening may allow the two connectors to be connected together to provide a simple and reliable electrical connection between the receiving coil and the PCB.

[0038] The receiving coil may be coated with a coating such as a manganese-zinc ferrite coating to improve the operating efficiency of the receiving coil. It will be understood that magnesium-zinc ferrites are magnetic materials with good electrical and magnetic properties, including a high permeability and saturation magnetisation, and low power losses and coercivity. The coating may be a polycrystalline manganese-zinc nano ferrite coating, for example, which has high covering power, is easily diluted and

[0039] P51801WO-6617 dispersed, and may be air dried without the need for curing at raised temperatures. The coating may be formed as a micron dry coating, for example.

[0040] The receiving coil may be coated with a protective coating to protect it against electromagnetic interference and electrostatic discharge (ESD), for example. The first outer sleeve may further comprise an anti-static coating on its inner surface. The antistatic coating may help to reduce the risk of the internal components of the aerosol generating device being damaged by ESD. Any suitable anti-static coating may be used, and it will preferably be flexible, durable and will not easily crack, chip or peel.

[0041] The aerosol generating article may comprise aerosol generating material.

[0042] The aerosol generating material 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 material 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. The solid or semi-solid aerosol generating material may be heated by the heater of the aerosol generating aerosol generating device - e.g., when arranged in the heating chamber.

[0043] The aerosol generating material may comprise an aerosol-former. Examples of aerosol-formers include polyhydric alcohols and mixtures thereof such as glycerine or propylene glycol. Typically, the aerosol generating material may comprise an aerosolformer content of between approximately 5% and approximately 50% on a dry weight basis. In some embodiments, the aerosol generating material may comprise an aerosol-former content of between approximately 10% and approximately 22% on a dry weight basis, and possibly approximately 15% on a dry weight basis.

[0044] The aerosol generating device may be adapted to heat the aerosol generating material or substrate, without burning the aerosol generating material, to volatise at least one

[0045] P51801WO-6617 component of the aerosol generating material and thereby generate a heated vapour which cools and condenses to form an aerosol for inhalation by a user of the aerosol generating device. The volatile compounds released from the aerosol generating material may include nicotine or flavour compounds such as tobacco flavouring.

[0046] 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 may 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, particularly with regard to the form of the inhalable medium that is generated for inhalation by a user.

[0047] When the aerosol generating material is depleted, the aerosol generating article may be removed from the aerosol generating device and a new article may be inserted.

[0048] The aerosol generating article may comprise a mouthpiece through which the generated aerosol may be inhaled.

[0049] Brief Description of the Drawings

[0050] Figure 1 is a diagrammatic view of an aerosol generating system including an aerosol generating device and an aerosol generating article;

[0051] Figure 2 is a diagrammatic view of the aerosol generating device of Figure 1 with a first outer sleeve omitted;

[0052] Figure 3 is a diagrammatic view of the aerosol generating device of Figure 1 with the first and second outer sleeves omitted;

[0053] Figure 4 is a diagrammatic view of a first side of a wireless charging assembly;

[0054] Figure 5 is a diagrammatic view of a second side of the wireless charging assembly of Figure 4 showing thermally conductive elements on the main surface of the substrate;

[0055] Figure 6 is a diagrammatic view of the aerosol generating device of Figure 1 with the wireless charging assembly omitted;

[0056] P51801WO-6617 Figure 7 is a detail view of the aerosol generating device of Figure 1 with the wireless charging assembly omitted;

[0057] Figure 8 is a diagrammatic perspective view of the aerosol generating device of Figure 7 with the wireless charging assembly omitted;

[0058] Figure 9 is a diagrammatic view of the aerosol generating device of Figure 7 with the thermally conductive elements omitted;

[0059] Figure 10 is a diagrammatic view of the aerosol generating device of Figure 9 with the metallic member omitted;

[0060] Figure 11 is a diagrammatic perspective view of the aerosol generating device of Figure 10;

[0061] Figure 12 is a diagrammatic view of a first side of a wireless charging assembly; and Figure 13 is a diagrammatic view of a second side of the wireless charging assembly of Figure 12 showing a thermally conductive element that completely covers a main surface of the substrate.

[0062] Detailed Description of Embodiments

[0063] Embodiments of the present disclosure will now be described by way of example only and with reference to the accompanying drawings.

[0064] Referring to Figures 1 to 11, an aerosol generating system 1 comprises an aerosol generating device 2 and an aerosol generating article 100.

[0065] The aerosol generating device 2 includes an inner assembly 4 with a heating chamber 6 that is shaped and sized to receive the aerosol generating article 100, which in this case may be formed as a stick containing tobacco material. A heater 8 is arranged next to the heating chamber 8 and is adapted to heat the aerosol generating article 100 when it is received in the heating chamber 8. The heating chamber 6 and the heater 8 are shown schematically in Figure 2.

[0066] A printed circuit board assembly (PCBA) 10 of the inner assembly 4 includes a printed circuit board (PCB) 12 and one or more electronic components. For example, a microcontroller unit (labelled “MCU”) implemented as an integrated circuit is

[0067] P51801WO-6617 mounted on a component side of the PCB 12 and controls operation of the aerosol generating device. The PCB 12 is partially covered by a metallic member 14 that may function as a shielding member and a heat sink for dissipating heat generated by the electronic components of the PCBA 10. In Figures 10 and 11 the metallic member 14 is omitted so that the underlying PCB 12 may be seen more clearly. The metallic member 14 includes a flap 14a that is raised above the plane of the remainder of the metallic member and which covers the MCU.

[0068] The aerosol generating device 2 further includes an energy storage device 16 (e.g., a rechargeable battery) adapted to supply power to the heater 6 to heat the aerosol generating article 100. The energy storage device 16 is shown schematically in Figure 3.

[0069] An outer housing 18 of the aerosol generating device 2 surrounds the inner assembly 4 and the energy storage device 16. The outer housing 18 includes a first outer sleeve 20 and a second outer sleeve 22. The first and second outer sleeves 20, 22 are arranged side-by-side as shown in Figure 1 and together define an exterior of the aerosol generating device 2. The first outer sleeve 20 is positioned at a first end 2a of the aerosol generating device 2 and surrounds a first end 4a of the inner assembly 4 that includes the heating chamber 6 and the heater 8. The second outer sleeve 22 is positioned at a second end 2b of the aerosol generating device 2, opposite the first end 2a, and surrounds a second end 4b of the inner assembly 4 and the energy storage device 16. In Figures 2, 3 and 6 to 11, the first outer sleeve 20 is omitted so that the inner assembly 4 and the wireless charging assembly 24 (see below) may be seen more clearly. In Figures 3 and 6, the second outer sleeve 22 is also omitted.

[0070] The first outer sleeve 20 is made of a non-metallic first material, e.g., a plastics material such as acrylonitrile butadiene styrene (ABS), having a first thermal conductivity.

[0071] The second outer sleeve 22 is made of a second material, e.g., aluminium, having a second thermal conductivity which is greater than the first thermal conductivity.

[0072] P51801WO-6617 The inner assembly 4 is in thermal contact with the second outer sleeve 22. For example, the outer surface of the second end 4a of the inner assembly may be in direct thermal contact with the inner surface of the second outer sleeve 22.

[0073] The aerosol generating device 2 includes a wireless charging assembly 24 arranged between an inner surface of the first outer sleeve 20 and the inner assembly 4. The wireless charging assembly 24 includes a receiving coil 26 for wireless inductive charging of the energy storage device 16, and a planar substrate 28. The substrate 28 is a ferrite sheet or a sheet of ferrite-containing material and includes a first main surface 28a and a second main surface 28b. The receiving coil 26 is mounted to the first main surface 28b. Although not shown, the receiving coil may also be embedded in the substrate. The receiving coil 26 is electrically connected to the PCB 12 by a pair of wires 30. The end of the wires 30 includes a connector 32 that is compatible with a connector 34 mounted to the PCB 24. For example, one of the connectors may be a male-type connector and the other may be a female-type connector that can be engaged together, i.e., the connectors are “plug-in” connectors. The connector 34 is aligned with an opening 36 in the metallic member 14 - see Figure 8, for example. Although not shown, the receiving coil 26 is in direct contact with the inner surface of the first outer sleeve 20. This also minimises the distance between the receiving coil 26 and the transmitting coil of an external wireless charger (not shown) during wireless charging, thereby improving charging efficiency.

[0074] Three thermally conductive elements are connected to the second main surface 28b of the substrate 28 and are in thermal contact with the inner assembly 4. The thermally conductive elements have a thermal conductivity that is greater than the first thermal conductivity, i.e., the thermal conductivity of the first outer sleeve 20.

[0075] The thermally conductive elements provide a thermal bridge between the wireless charging assembly 24 and the inner assembly 4. The aerosol generating device 2 is therefore designed to provide a heat flow path to transfer and dissipate heat generated by the wireless charging assembly 24, e.g., during wireless charging. A heat flow path

[0076] P51801WO-6617 is provided from the wireless charging assembly 24 to the outside environment - i.e., from the receiving coil 26 through the substrate 28 and the thermally conductive elements to the inner assembly 4, and then from the inner assembly 4 to the outside environment through the second outer sleeve 22.

[0077] The inner assembly 4 also includes a separate heat sink 38 that is arranged to dissipate the heat of the PCBA 10. As shown most clearly in Figure 8, the heat sink 38 includes a main part that is substantially planar and is in thermal contact with the support frame or body of the inner assembly 4. A tab part is provided at an edge of the main part of the heat sink 38 and is in thermal contact with the PCB 12. The heat sink 38 is therefore designed to transfer heat from the PCB 12 to the support frame or body of the inner assembly 4 where it is dissipated or transferred to the outside environment through the second outer sleeve 20. The main part and the tab part are arranged substantially perpendicular.

[0078] The thermally conductive elements include a pair of thermally conductive elastomeric pads 40, 42 that span the gap between the second main surface 28b of the substrate 28 and the facing outer surface of the metallic member 14, and a strip of thermally conductive self-adhesive tape 44. The thermally conductive self-adhesive tape 44 also adheres the substrate 28 to the facing surface of the heat sink 38, i.e., to the planar outer surface of the main part of the heat sink 38. Figures 6 to 8 show how the elastomeric pads 40, 42 are positioned so that they avoid contacting the flap 14a of the metallic member 14 that overlies the MCU so that heat is not transferred to this area of the metallic member. This prevents the MCU from being damaged.

[0079] Figures 12 and 13 show an alternative arrangement where the second main surface of the substrate 28 is completely covered by a strip of thermally conductive self-adhesive tape 44.

[0080] Although not shown, the first outer sleeve 20 may include a metallic coating - e.g., a coating of a metal or metal alloy such as copper or nickel. The metallic coating of the first outer sleeve 20 may be formed by electroplating, for example. The metallic

[0081] P51801WO-6617 coating may improve the thermal conductivity of the first outer sleeve 20, but will not normally extend on that part of the first outer sleeve 20 that covers the receiving coil 26 for the reasons described above.

[0082] The second outer sleeve 22 may alternatively be made of a suitable plastics material such as ABS with a metallic coating - e.g., a coating of a metal or metal alloy such as copper or nickel. The metallic coating of the second outer sleeve 22 may be formed by electroplating, for example. The metallic coating may improve the thermal conductivity of the second outer sleeve 20 if it is formed mainly of a plastics material.

[0083] The receiving coil 26 may be coated with a coating such as a manganese-zinc ferrite coating to improve the operating efficiency of the receiving coil 26. The coating may be a polycrystalline manganese-zinc nano ferrite coating, which has high covering power, is easily diluted and dispersed, and may be air dried without the need for curing. The coating may be formed as a micron dry coating, for example.

[0084] The receiving coil 26 may be coated with a protective coating to protect it against electromagnetic interference and electrostatic discharge (ESD), for example.

[0085] The first outer sleeve 20 may further comprise an anti-static coating on its inner surface. The anti-static coating may help to reduce the risk of the internal components of the aerosol generating device 2 being damaged by ESD. Any suitable anti-static coating may be used, and it will preferably be flexible, durable and will not easily crack, chip or peel.

[0086] 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.

[0087] P51801WO-6617 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”.

[0088] P51801WO-6617

Claims

Claims1. An aerosol generating device (2) comprising: an inner assembly (4) comprising: a heating chamber (6) adapted to receive an aerosol generating article (100); a heater (8) adapted to heat the aerosol generating article (100) when received in the heating chamber (6); and a printed circuit board assembly PCBA (10) comprising a printed circuit board PCB (12) and one or more electronic components adapted to control operation of the aerosol generating device (2); an energy storage device (16) adapted to supply power to the heater (8); an outer housing (18) that substantially surrounds the inner assembly (4) and the energy storage device (16), the outer housing (18) comprising: a first outer sleeve (20) comprising a non-metallic first material having a first thermal conductivity; a wireless charging assembly (24) arranged between an inner surface of the first outer sleeve (20) and the inner assembly (4), the wireless charging assembly (24) comprising: a receiving coil (26) for wireless inductive charging; and a planar substrate (28) having a first main surface (28a) facing the inner surface of the first outer sleeve (20), and a second main surface (28b) opposite the first main surface (28a), wherein the receiving coil (26) is embedded in the substrate (28) or mounted to the first main surface (28a) of the substrate (28); and one or more thermally conductive elements (40, 42, 44) connected to at least a part of the second main surface (28b) of the planar substrate (28) of the wireless charging assembly (24) and arranged between the wireless charging assembly (24) and the inner assembly (4), wherein the one or more thermally conductive elements (40, 42, 44) are in contact with the inner assembly.

2. An aerosol generating device (2) according to claim 1, wherein the outer housing (18) further comprises a second outer sleeve (22) comprising a secondP51801WO-6617material having a second thermal conductivity which is greater than the first thermal conductivity, and wherein the inner assembly (4) is in contact with the second outer sleeve (22).

3. An aerosol generating device (2) according to claim 1 or claim 2, wherein the inner assembly (4) further comprises a metallic member (14) at least partially covering a component side of the PCB (12) on which the one or more electronic components are mounted, the component side of the PCB (12) facing the second main surface (28b) of the substrate (28), and wherein at least part of one of the one or more thermally conductive elements (40, 42) is in contact with at least a part of the metallic member (14).

4. An aerosol generating device (2) according to claim 3, wherein the one or more electronic components comprises a controller (MCU) mounted to the PCB (12) and adapted to control operation of the aerosol generating device (2), and the PCBA (10) further comprises a connector (34) adapted to electrically connect the wireless charging assembly (24) to the PCBA (10).

5. An aerosol generating device (2) according to claim 4, wherein the metallic member (14) comprises an opening (36) that corresponds to the position of the connector (34).

6. An aerosol generating device (2) according to any preceding claim, wherein the inner assembly (4) further comprises at least one heat sink (38) arranged for dissipating heat of the PCBA (10), the at least one heat sink (38) being in contact with at least a part of the one or more thermally conductive elements (44).

7. An aerosol generating device (2) according to any preceding claim, wherein the one or more thermally conductive elements comprise a thermally conductive elastomeric pad (40, 42) and / or a thermally conductive self-adhesive tape (44).P51801WO-66178. An aerosol generating device (2) according to any preceding claim, wherein a thickness of each of the one or more thermally conductive elements (40, 42) is selected such that each of the one or more thermally conductive elements (40, 42) substantially spans a gap between the second main surface (28b) of the substrate (28) and the inner assembly (4).

9. An aerosol generating device (2) according to claim 7 or claim 8, wherein the one or more thermally conductive elements is a thermally conductive self-adhesive tape (44) having a shape which is substantially completely overlapped with the second main surface (28b) of the planar substrate (28) of the wireless charging assembly (24).

10. An aerosol generating device (2) according to any preceding claim, wherein the first outer sleeve (20) comprises a plastics material.

11. An aerosol generating device (2) according to claim 10, wherein the first outer sleeve further comprises a metallic coating.

12. An aerosol generating device (2) according to claim 2, wherein the second outer sleeve (22) comprises a metal material.

13. An aerosol generating device (2) according to claim 2, wherein the second outer sleeve comprises a plastics material and a metallic coating.

14. An aerosol generating device (2) according to any preceding claim, wherein the receiving coil is coated with a manganese-zinc ferrite coating.

15. An aerosol generating device (2) according to any preceding claim, wherein the first outer sleeve (20) further comprises an anti-static coating on its inner surface.P51801WO-6617

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