Aerosol generating device having a thermally conductive assembly

Abstract

An aerosol generating device (10) is provided that includes an aerosol generator (18) for generating an aerosol from an aerosol-forming substrate, a power supply (24), and a circuit board (28) that includes control circuitry (30) for controlling the supply of power from the power supply (24) to the aerosol generator (18). The aerosol generating device (10) also includes a thermally conductive assembly (46) that has a first end (48) in thermal contact with the circuit board (28) and a second end (50) spaced apart from the circuit board (28).

Description

[Technical field]

[0001] The present invention relates to an aerosol generating device that includes a thermally conductive assembly. [Background technology]

[0002] Aerosol generating systems in which an aerosol-forming substrate, such as a tobacco-containing substrate, is heated rather than combusted are well known in the art. The purpose of such aerosol generating systems is to reduce the well-known harmful smoke components produced by the combustion and pyrolytic degradation of tobacco in conventional cigarettes. Typically in such aerosol generating systems, an aerosol is generated by the transfer of energy from an aerosol generator of an aerosol generating device to an aerosol-forming substrate or material in an aerosol-generating article that is physically separate from the aerosol generating device. For example, the aerosol generator may be an electric heater, and the aerosol may be generated by the transfer of heat from the electric heater to the aerosol-forming substrate. The aerosol-generating article may be located in, around, or downstream of the electric heater. During use, volatile compounds are released from the aerosol-forming substrate by the transfer of heat from the electric heater to the aerosol-forming substrate and are entrained in the air drawn through the aerosol-generating article. As the released compounds cool, they condense to form an aerosol that can be inhaled by the consumer. Summary of the Invention [Problem to be solved by the invention]

[0003] During use of such aerosol generating devices, the control circuitry for controlling the supply of power to the electric heater typically generates a significant amount of heat. Dissipation of the heat generated by the control electronics is necessary to prevent damage to the control circuitry. However, the small size of typical aerosol generating devices, coupled with the need for the user to hold the device during use, makes such dissipation of excess heat difficult.

[0004] It will be described that it is possible to provide an aerosol generating device comprising an aerosol generator and a control circuit that facilitates dissipation of excess heat generated by the control circuit. [Means for solving the problem]

[0005] According to the present disclosure, there is provided an aerosol generating device. The aerosol generating device may comprise an aerosol generator. The aerosol generator may be for generating an aerosol from an aerosol-forming substrate. The aerosol generating device may comprise a power supply. The aerosol generating device may comprise a circuit board. The circuit board may comprise control circuitry. The control circuitry may be for controlling the supply of power from the power supply to the aerosol generator. The circuit board and the power supply may be arranged for the transfer of heat from the circuit board to the power supply.

[0006] According to the present disclosure, there is provided an aerosol generating device comprising an aerosol generator for generating an aerosol from an aerosol-forming substrate, a power supply, and a circuit board comprising control circuitry for controlling the supply of power from the power supply to the aerosol generator, the circuit board and the power supply being arranged for the transfer of heat from the circuit board to the power supply.

[0007] The circuit board and power supply are preferably arranged for conductive heat transfer from the circuit board to the power supply.

[0008] The circuit board may be in direct contact with the power source. Advantageously, direct contact between the circuit board and the power source may facilitate direct conductive heat transfer from the circuit board to the power source.

[0009] The circuit board and the power source may be arranged for indirect conductive heat transfer from the circuit board to the power source. In other words, the aerosol generating device may comprise at least one additional element arranged for conductive heat transfer from the circuit board to the power source by the at least one additional element. Advantageously, the at least one additional element may facilitate a desired orientation and position of the circuit board relative to the power source while providing conductive heat transfer from the circuit board to the power source. The desired orientation and position of the circuit board relative to the power source may be compatible with at least one of a desired size and a desired shape of the aerosol generating device.

[0010] The at least one additional element may include a thermally conductive assembly having a first end in thermal contact with the circuit board and a second end spaced apart from the circuit board.

[0011] According to the present disclosure, there is provided an aerosol generating device. The aerosol generating device may comprise an aerosol generator. The aerosol generator may be for generating an aerosol from an aerosol-forming substrate. The aerosol generating device may comprise a power source. The aerosol generating device may comprise a circuit board. The circuit board may comprise control circuitry. The control circuitry may be for controlling the supply of power from the power source to the aerosol generator. The aerosol generating device may comprise a thermally conductive assembly. The thermally conductive assembly may comprise a first end in thermal contact with the circuit board. The thermally conductive assembly may comprise a second end spaced apart from the circuit board.

[0012] According to the present disclosure, there is provided an aerosol generating device comprising an aerosol generator for generating an aerosol from an aerosol-forming substrate, a power source and a circuit board comprising control circuitry for controlling the supply of power from the power source to the aerosol generator. The aerosol generating device also comprises a thermally conductive assembly having a first end in thermal contact with the circuit board and a second end spaced from the circuit board.

[0013] Advantageously, the thermally conductive assembly conducts excess heat away from the circuit board and towards the second end of the thermally conductive assembly. Advantageously, the thermally conductive assembly provides at least some control over where excess heat from the circuit board is transferred. Advantageously, the second end of the thermally conductive assembly may be positioned where it is desired to dissipate excess heat generated by the control circuitry.

[0014] As used herein, the term "aerosol-generating device" refers to a device that interacts with an aerosol-forming substrate to generate an aerosol.

[0015] The term "aerosol-forming substrate" as used herein refers to a substrate capable of releasing volatile compounds capable of forming an aerosol. Such volatile compounds may be released by heating the aerosol-forming substrate. The aerosol-forming substrate may form part of an aerosol-generating article.

[0016] The term "aerosol-generating article" as used herein refers to an article that includes an aerosol-forming substrate capable of releasing a volatile compound capable of forming an aerosol. For example, the aerosol-generating article may be an article that generates an aerosol that can be directly inhaled by a user sucking or puffing on a mouthpiece at the proximal or user end of the system. The aerosol-generating article may be disposable. An article that includes an aerosol-forming substrate that includes tobacco may be called a tobacco stick.

[0017] As used herein, the term "aerosol generating system" refers to the combination of an aerosol generating device and an aerosol generating article. In an aerosol generating system, the aerosol generating article and the aerosol generating device work together to generate an aerosol.

[0018] The second end of the thermally conductive assembly is preferably in thermal contact with the power source.

[0019] Advantageously, there may be a high thermal gradient between the circuit board and the power supply during use. Advantageously, the high thermal gradient and thermal contact between the second end of the thermally conductive assembly and the power supply may increase or maximize the rate of heat transfer away from the circuit board by the thermally conductive assembly.

[0020] Advantageously, transferring heat from the circuit board to the power supply may facilitate use of the aerosol generating device in cool ambient temperatures. For example, at temperatures below about 5 degrees Celsius, the performance of some power supplies may decrease. Thus, transferring heat from the circuit board to the power supply may advantageously raise the temperature of the power supply above the ambient temperature. Advantageously, raising the temperature of the power supply above the ambient temperature may maintain or improve the performance of the power supply.

[0021] The thermally conductive assembly preferably includes a thermally conductive frame defining a second end of the thermally conductive assembly. The power source is preferably located at least partially within the thermally conductive frame.

[0022] Advantageously, providing the thermally conductive assembly with a thermally conductive frame may facilitate positioning of the power source and the thermally conductive assembly relative to one another during assembly of the aerosol generating device.

[0023] Advantageously, positioning the power supply within the thermally conductive frame may facilitate the transfer of heat from the second end of the thermally conductive assembly to the power supply.

[0024] An aerosol generating device as described in any one of the preceding claims, wherein the thermally conductive assembly comprises at least one transverse member at a first end of the thermally conductive assembly, and a portion of the at least one transverse member is positioned within a slot defined by the circuit board.

[0025] Advantageously, providing the thermally conductive assembly with at least one transverse member positioned within a slot defined by the circuit board may facilitate thermal contact between the circuit board and a first end of the thermally conductive assembly.

[0026] Advantageously, providing the thermally conductive assembly with at least one transverse member positioned within a slot defined by the circuit board may aid in holding a first end of the thermally conductive assembly in thermal contact with the circuit board. Advantageously, the combination of the at least one transverse member and the slot may eliminate the need to solder or glue the first end of the thermally conductive assembly to the circuit board. Advantageously, eliminating the need to solder or glue the first end of the thermally conductive assembly to the circuit board may simplify at least one of the manufacture and repair of the aerosol generating device.

[0027] Advantageously, providing the thermally conductive assembly with at least one transverse member positioned within a slot defined by the circuit board may facilitate positioning of the circuit board and the thermally conductive assembly relative to one another during assembly of the aerosol generating device.

[0028] The at least one transverse member is preferably received in the slot by an interference fit. Advantageously, the interference fit may facilitate thermal contact between the at least one transverse member and the circuit board. Advantageously, the interference fit may facilitate retention of the at least one transverse member in the slot.

[0029] The at least one transverse member may comprise a plurality of transverse members. The circuit board may define a plurality of slots, each of the transverse members being received within a different slot defined by the circuit board.

[0030] Advantageously, providing a plurality of transverse members may increase the rate of heat transfer from the circuit board to the first end of the thermally conductive assembly.

[0031] Advantageously, providing a plurality of transverse members may facilitate thermal contact between a first end of the thermally conductive assembly and a plurality of locations on the circuit board. Advantageously, the plurality of locations may be selected to provide a desired profile of heat transfer from the circuit board to the first end of the thermally conductive assembly. For example, if heat generated by the control circuitry results in a non-uniform temperature distribution across at least a portion of the circuit board during use, the plurality of transverse members may be positioned to conform to the non-uniform temperature profile.

[0032] Advantageously, providing multiple transverse members may make it easier to position the circuit board and the thermally conductive assembly relative to one another during assembly of the aerosol generating device.

[0033] The slot defined by the circuit board may be a first slot and the circuit board may define a second slot, and the at least one transverse member may include a first transverse member having a first portion positioned in the first slot and a second transverse member having a second portion positioned in the second slot.

[0034] The slot defined by the circuit board may extend through the circuit board from a first side of the circuit board to a second side of the circuit board. The at least one transverse member may extend through the slot such that the at least one transverse member protrudes from the first side of the circuit board and from the second side of the circuit board. In other words, the at least one transverse member may extend completely through a thickness of the circuit board.

[0035] Advantageously, transverse members extending completely through the thickness of the circuit board may increase or maximize the thermal contact area between the at least one transverse member and the circuit board.

[0036] The thermally conductive assembly may include at least one longitudinal arm extending between the at least one transverse member and the thermally conductive frame.

[0037] Advantageously, the at least one longitudinal arm may facilitate transfer of heat from the at least one transverse member at a first end of the thermally conductive assembly to a thermally conductive frame at a second end of the thermally conductive assembly.

[0038] Advantageously, the at least one longitudinal arm may be flexible. Advantageously, a flexible at least one longitudinal arm may facilitate positioning of the at least one transverse member within the slot during assembly of the aerosol generation device.

[0039] In embodiments in which the thermally conductive assembly comprises a plurality of transverse members, the thermally conductive assembly preferably comprises a plurality of longitudinal arms, each longitudinal arm preferably extending between one of the transverse members and the thermally conductive frame.

[0040] In embodiments in which the thermally conductive assembly comprises a first transverse member and a second transverse member, the at least one longitudinal arm preferably comprises a first longitudinal arm extending between the first transverse member and the thermally conductive frame, and a second longitudinal arm extending between the second transverse member and the thermally conductive frame.

[0041] The circuit board may be a first circuit board and the aerosol generating device may further comprise a second circuit board. The first end of the thermally conductive assembly is preferably in thermal contact with the first circuit board and the second circuit board.

[0042] Advantageously, the first circuit board and the second circuit board may facilitate providing the aerosol generation device with at least one of a desired size and a desired shape For example, the first circuit board and the second circuit board may facilitate the aerosol generation device having a shorter length as compared to an aerosol generation device including a single circuit board.

[0043] Advantageously, the first circuit board and the second circuit board may facilitate separation of two or more electrical components of the aerosol generating device. Advantageously, providing a first set of electrical components on the first circuit board and a second set of electrical components on the second circuit board may facilitate thermal separation of the first set of electrical components and the second set of electrical components.

[0044] The second circuit board is preferably at least partially overlying the first circuit board. Advantageously, being at least partially overlying the first and second circuit boards may facilitate the first end of the thermally conductive assembly being in thermal contact with both the first and second circuit boards.

[0045] The first end of the thermally conductive assembly is preferably positioned between the first circuit board and the second circuit board. Advantageously, positioning the first end of the thermally conductive assembly between the first circuit board and the second circuit board may facilitate the first end of the thermally conductive assembly being in thermal contact with both the first circuit board and the second circuit board.

[0046] A control circuit for controlling the supply of power from the power source to the aerosol generator is preferably provided on the first circuit board. The aerosol generator is preferably electrically connected to the first circuit board.

[0047] As used herein, the term "electrically connected" refers to a connection by means of a conductive pathway.

[0048] The power source is preferably electrically connected to at least one of the first circuit board and the second circuit board, and may be electrically connected to both the first circuit board and the second circuit board.

[0049] The aerosol generating device preferably includes one or more additional electrical components, preferably including at least one of a charging connector, a feedback device, a user input device, and an airflow sensor, and at least one of the one or more additional electrical components is preferably located on or electrically connected to a second circuit board.

[0050] The aerosol generating device preferably comprises a device controller configured to control operation of the aerosol generating device. The device controller is preferably provided on a second circuit board. The device controller is preferably in electrical communication with one or more additional electrical components. The device controller is preferably electrically connected to the power source. The device controller is preferably in electrical communication with control circuitry for controlling the supply of power from the power source to the aerosol generator. The first circuit board is preferably electrically connected to the second circuit board. The electrical connection between the first circuit board and the second circuit board preferably provides electrical communication between the device controller and control circuitry for controlling the supply of power from the power source to the aerosol generator.

[0051] In embodiments in which the thermally conductive assembly includes at least one transverse member, at least a portion of the at least one transverse member is preferably positioned within a slot defined by the second circuit board. Advantageously, positioning the at least one transverse member within a slot defined by the first and second circuit boards may facilitate transfer of heat by the thermally conductive assembly away from both the first and second circuit boards.

[0052] In embodiments where the at least one cross member comprises a plurality of cross members, at least one of the cross members may be received within a slot defined by the first circuit board and a slot defined by the second circuit board, and at least one of the cross members may have a first end received within the slot defined by the first circuit board and a second end received within the slot defined by the second circuit board.

[0053] Advantageously, providing at least one transverse member received in a slot defined by the first circuit board and the second circuit board may reduce or minimize the number of transverse members required to provide desired thermal contact between the first end of the thermally conductive assembly and each of the first circuit board and the second circuit board.

[0054] At least one of the transverse members is preferably in thermal contact only with the first circuit board. Advantageously, providing a transverse member in thermal contact only with the first circuit board may facilitate a higher rate of heat transfer away from the first circuit board by the thermally conductive assembly compared to the rate of heat transfer away from the second circuit board by the thermally conductive assembly. Advantageously, the higher rate of heat transfer away from the first circuit board by the thermally conductive assembly may accommodate a significant amount of heat generated by a control circuit for controlling the supply of power from the power source to the aerosol generator.

[0055] As described herein, the thermally conductive assembly may include a first transverse member positioned within a first slot defined by the first circuit board and a second transverse member positioned within a second slot defined by the first circuit board. The second circuit board preferably defines a third slot and the second transverse member has a third portion positioned within the third slot. The first transverse member is preferably in thermal contact only with the first circuit board.

[0056] The thermally conductive assembly is formed from a thermally conductive material that preferably has a thermal conductivity of at least about 190 watts per meter Kelvin at 23 degrees Celsius and 50 percent relative humidity as measured using a modified transient plane source (MTPS) method.

[0057] Suitable thermally conductive materials may include metals. The thermally conductive assembly may be metallic. Suitable metals include aluminum, copper, iron, gold, zinc, or any suitable alloys of such metals. Suitable alloys include some stainless steels and some copper alloys, such as brass, copper-nickel alloys, copper-beryllium alloys, and phosphor bronze.

[0058] The thermally conductive assembly is preferably formed from brass. Advantageously, brass may be sufficiently malleable to facilitate formation of a thermally conductive assembly having a required shape. Advantageously, a thermally conductive assembly formed from brass may be sufficiently resilient to facilitate retention of one or more components of an aerosol generating device by the thermally conductive assembly. For example, in embodiments in which the thermally conductive assembly comprises a thermally conductive frame, a brass thermally conductive assembly may be sufficiently resilient to facilitate retention of a power source within the thermally conductive frame.

[0059] The aerosol generating device may comprise an inner housing. Advantageously, the inner housing may support one or more components of the aerosol generating device.

[0060] The circuit board may be secured to the inner housing. The circuit board may be secured to the housing by an interference fit between a portion of the circuit board and the inner housing. In embodiments in which the aerosol generating device comprises a first circuit board and a second circuit board, the first circuit board and the second circuit board may be secured to the inner housing.

[0061] The power source is preferably located within the inner housing.

[0062] The second end of the thermally conductive assembly is preferably in thermal contact with the inner housing. Advantageously, the thermal contact between the thermally conductive assembly and the inner housing may facilitate dissipation of heat from the circuit board to the inner housing by the thermally conductive assembly.

[0063] In embodiments in which the thermally conductive assembly comprises a thermally conductive frame, the thermally conductive frame is preferably in thermal contact with the inner housing.

[0064] At least a portion of the second end of the thermally conductive assembly may overlie a portion of the inner housing.

[0065] A portion of the inner housing is preferably overmolded onto at least a portion of the second end of the thermally conductive assembly. Advantageously, overmolding a portion of the inner housing onto at least a portion of the second end of the thermally conductive assembly may embed at least a portion of the second end of the thermally conductive assembly within the material forming the inner housing. Advantageously, embedding at least a portion of the thermally conductive assembly within the material forming the inner housing may facilitate the transfer of heat from the second end of the thermally conductive assembly to the inner housing.

[0066] In embodiments in which the second end of the thermally conductive assembly comprises a thermally conductive frame, a portion of the inner housing is preferably overmolded onto the outside of at least a portion of the thermally conductive frame.

[0067] The inner housing is preferably formed of a material suitable for molding onto the outside of the thermally conductive assembly. The inner housing may be formed of a polymeric material. The inner housing may be formed of a moldable polymer. The inner housing is preferably formed of a material suitable for use in a molding process such as injection molding. Suitable polymeric materials include thermoplastic materials and thermosetting polymers. Suitable polymeric materials include polyphthalamide (PPA), polycarbonate (PC), blends of polycarbonate and acrylonitrile butadiene styrene (PC-ABS), polyphenylsulfone (PPSU), polyetheretherketone (PEEK), polypropylene (PP), polyethylene (PE), polyimide (PI), thermoplastic polyimide (TPI), polyamideimide (PAI), and polyetherimide (PEI). The polymeric material may be a composite polymeric material. The composite polymeric material may include other materials. The composite polymeric material may include at least one fibrous filler material. The at least one fibrous filler material may include at least one of carbon fiber and glass fiber.

[0068] The control circuitry for controlling the supply of power from the power supply to the aerosol generator may comprise at least one of a microprocessor, a microcontroller, and an application specific integrated chip (ASIC).

[0069] In embodiments in which the aerosol generating device includes a device controller, the device controller may include at least one of a microprocessor, a microcontroller, and an application specific integrated chip (ASIC).

[0070] The power source may be a DC power source. In a preferred embodiment, the power source is a battery. The power source may be a nickel metal hydride battery, a nickel cadmium battery, or a lithium-based battery (e.g., lithium cobalt, lithium iron phosphate, or lithium polymer battery). The power source may be another form of charge storage device, such as a capacitor. The power source may require recharging and may have a capacity that allows for the storage of sufficient energy for one or more user actions, such as one or more aerosol generating experiences. For example, the power source may have a capacity sufficient to allow continuous heating of the aerosol-forming substrate for about 6 minutes, or a multiple of 6 minutes, corresponding to the typical time it takes to smoke one conventional cigarette. In another embodiment, the power source may have a capacity sufficient to allow for a predetermined number of puffs, or for discontinuous activation of the heater.

[0071] The aerosol generating device preferably comprises a cavity for receiving the aerosol-forming substrate. In embodiments in which the aerosol generating device comprises an inner housing, the inner housing may at least partially define the cavity.

[0072] The aerosol generating device preferably comprises an outer housing. In embodiments in which the aerosol generating device comprises a cavity for receiving the aerosol-forming substrate, the outer housing may at least partially define the cavity.

[0073] The housing may be elongated. The housing may have a cylindrical shape. The housing may comprise any suitable material or combination of materials. Suitable materials include metals, alloys, plastics, and composites containing at least one of metals, alloys, and plastics. Suitable materials include thermoplastics suitable for food or pharmaceutical applications. Suitable thermoplastics include polypropylene, polyetheretherketone (PEEK), and polyethylene.

[0074] The aerosol generating device is preferably portable. The aerosol generating device may have a length of about 70 mm to about 120 mm. The aerosol generating device is preferably a handheld device. In other words, the aerosol generating device may be sized and shaped to be held in a user's hand.

[0075] The aerosol generator may include an electric heater.

[0076] The electric heater may comprise at least one internal heating element. As used herein, the term "internal heating element" refers to a heating element configured to be inserted into the aerosol-forming substrate. The internal heating element may be in the form of at least one of a blade, a pin, and a cone. The internal heating element is preferably configured to be insertable into the aerosol-forming substrate. In embodiments in which the aerosol generating device comprises a cavity for receiving the aerosol-forming substrate, the at least one internal heating element preferably extends into the cavity.

[0077] The electric heater may comprise at least one external heating element. As used herein, the term "external heating element" refers to a heating element configured to heat the outer surface of the aerosol-forming substrate. The at least one external heating element is preferably configured to at least partially surround the aerosol-forming substrate received by the aerosol-generating device. In embodiments in which the aerosol-generating device comprises a cavity for receiving the aerosol-forming substrate, the at least one external heating element preferably at least partially surrounds the cavity.

[0078] The electric heater may comprise at least one internal heating element and at least one external heating element.

[0079] In some preferred embodiments, the heater comprises at least one resistive heating element.

[0080] The electric heater may comprise a resistive heating element. The resistive heating element may comprise an electrically insulating substrate and one or more conductive tracks or wires provided on a surface of the electrically insulating substrate. The size and shape of the electrically insulating substrate may facilitate insertion of the electric heater into the aerosol-forming substrate. The electrically insulating substrate is preferably rigid. The aerosol generating device may comprise only one resistive heating element. The aerosol generating device may comprise multiple resistive heating elements.

[0081] The aerosol generator may comprise a moving element. The moving element may be arranged to move the liquid aerosol-forming substrate to the electric heater. The moving element may comprise a capillary wick. The electric heater is preferably in contact with the moving element. The electric heater may comprise a resistive heating wire. At least a portion of the resistive heating wire may be coiled around the moving element. The electric heater may comprise a resistive heating mesh.

[0082] The aerosol generator may comprise an induction heating arrangement. The induction heating arrangement may comprise an inductor coil. The control circuit for controlling the supply of power from the power source to the aerosol generator is preferably configured to provide a high frequency oscillating current from the power source to the inductor coil. As used herein, the term "high frequency oscillating current" refers to an oscillating current having a frequency between 500 kilohertz and 30 megahertz. The aerosol generating device may comprise a DC / AC inverter for converting a DC current provided by a DC power source to an oscillating current. The inductor coil may be arranged to generate a high frequency oscillating electromagnetic field upon receiving the high frequency oscillating current from the power source. The inductor coil may be arranged to generate a high frequency oscillating electromagnetic field in a device cavity configured to receive an aerosol-forming substrate. In an embodiment in which the aerosol generating device comprises a cavity for receiving an aerosol-forming substrate, the inductor coil may substantially surround the cavity. The inductor coil may extend at least partially along a length of the cavity.

[0083] In embodiments where the aerosol generator comprises an induction heating arrangement, the aerosol generator may comprise an induction heating element. The induction heating element may be a susceptor element. As used herein, the term "susceptor element" refers to an element comprising a material capable of converting electromagnetic energy into heat. When the susceptor element is located within the oscillating electromagnetic field, the susceptor is heated. The heating of the susceptor element may be the result of at least one of hysteresis losses and eddy currents induced within the susceptor element, depending on the electrical and magnetic properties of the susceptor material. In embodiments where the aerosol generating device comprises a cavity for receiving an aerosol-forming substrate, the susceptor element may be arranged such that when the aerosol-forming substrate is received within the cavity, the oscillating electromagnetic field generated by the inductor coil induces electrical currents within the susceptor element, causing the susceptor element to heat the aerosol-forming substrate. The susceptor element may be positioned within the cavity. The aerosol generating device may comprise only one susceptor element. The aerosol generating device may comprise multiple susceptor elements.

[0084] The susceptor element may comprise any suitable material. The susceptor element may be formed from any material that can be inductively heated to a temperature sufficient to release the volatile compound from the aerosol-forming substrate. The susceptor element may comprise metal or carbon. Suitable materials for the susceptor element include graphite, molybdenum, silicon carbide, stainless steel, niobium, aluminum, nickel, nickel-containing compounds, titanium, and composites of metallic materials. The susceptor element may comprise ferromagnetic materials, such as ferromagnetic alloys, e.g., ferritic iron, ferromagnetic steel or stainless steel, ferromagnetic particles, and ferrites.

[0085] In embodiments in which the aerosol generator comprises an inductive heating arrangement, the aerosol generator may comprise only an inductor coil. In other words, the aerosol-generating device may not comprise any susceptor element. The aerosol-generating device may receive an aerosol-generating article comprising an aerosol-forming substrate and at least one susceptor element. In use, the oscillating electromagnetic field generated by the inductor coil induces a current in the susceptor element of the aerosol-generating article, causing the susceptor element to heat the aerosol-forming substrate.

[0086] The aerosol generator may comprise an element arranged to vibrate when power is provided from the power source. The aerosol generator may comprise a piezoelectric element. The aerosol generator may comprise at least one nozzle. The piezoelectric element may be arranged to eject droplets of the liquid aerosol-forming substrate through the at least one nozzle. The aerosol generating device may comprise a mesh, the mesh defining the at least one nozzle.

[0087] The mesh may be arranged to vibrate during use of the aerosol generating device. A vibrating mesh may be referred to as an "active mesh". The mesh may be formed from a piezoelectric material. The mesh may be a piezoelectric element. The piezoelectric element may be formed separately from the mesh and arranged to vibrate the mesh during use.

[0088] The mesh may be arranged to remain substantially stationary relative to the vibrating piezoelectric element during use of the aerosol generating device. A stationary mesh may be referred to as a "passive mesh". The aerosol generator may comprise a reservoir positioned between the mesh and the piezoelectric element. The reservoir may be arranged to receive a liquid aerosol-forming substrate.

[0089] Embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which: [Brief description of the drawings]

[0090] [Figure 1] FIG. 1 shows a schematic cross-sectional view of an aerosol generating device according to a first embodiment of the present invention. [Diagram 2] FIG. 2 illustrates the electrical connections between the electrical components of the aerosol generating device of FIG. [Diagram 3] FIG. 3 shows a top perspective view of the aerosol generating device of FIG. 1 with the outer housing removed. [Figure 4] FIG. 4 shows a bottom perspective view of the aerosol generating device of FIG. 1 with the outer housing removed. [Diagram 5] FIG. 5 shows a perspective view of the thermally conductive assembly of the aerosol generating device of FIG. [Figure 6] FIG. 6 shows an alternative arrangement of a thermally conductive assembly with respect to the inner housing of the aerosol generating device of FIG. [Figure 7] FIG. 7 shows a schematic cross-sectional view of an aerosol generating device according to a second embodiment of the present invention. [Figure 8] FIG. 8 shows a schematic cross-sectional view of an aerosol generating device according to a third embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0091] 1 shows a schematic cross-sectional view of an aerosol generation device 10 according to a first embodiment of the present invention. The aerosol generation device 10 comprises an inner housing 12 defining a cavity 14 for receiving an aerosol-forming substrate at a first end of the aerosol generation device 10. The aerosol generation device 10 also comprises an outer housing 16 extending around the inner housing 12.

[0092] The aerosol generating device 10 also comprises an aerosol generator 18 comprising an induction heating arrangement. The induction heating arrangement comprises an inductor coil 20 surrounding the cavity 14. During use, an aerosol-forming article, including an aerosol-forming substrate and a susceptor element, is inserted into the cavity 14.

[0093] A power source 24 is positioned within the inner housing 12 at a second end of the aerosol generating device 10. The power source 24 is a rechargeable battery.

[0094] The aerosol generation device 10 also includes several control components, broadly illustrated by box 26 in Figure 1. The control components and their functional connectivity to each other (illustrated by the connecting arrows) are shown in more detail in the schematic diagram of Figure 2.

[0095] The aerosol generating device 10 comprises a first circuit board 28 on which control circuitry 30 is provided. The control circuitry 30 is configured to control the supply of power from the power supply 24 to the aerosol generator 18. In particular, the control circuitry 30 comprises a DC / AC inverter for converting a supply of DC power from the power supply 24 into an oscillating current that is supplied to the inductor coil 20. In use, the oscillating current in the inductor coil 20 generates a high frequency oscillating electromagnetic field within the cavity 14. The high frequency oscillating electromagnetic field inductively heats a susceptor element of an aerosol-generating article received within the cavity 14, which in turn heats an aerosol-forming substrate of the aerosol-generating article.

[0096] The puff sensor 32 is disposed within or in communication with the cavity 14. The puff sensor is disposed to sense when a user draws air through the cavity 14 and inhales an aerosol generated by an aerosol-forming substrate received within the cavity 14. The puff sensor 32 includes a pressure sensor. The puff sensor 32 is electrically connected to the first circuit board 28 for communicating data generated by the puff sensor 32 to the control circuit 30.

[0097] The aerosol generating device 10 also includes a second circuit board 34 on which a device controller 36 is provided. The device controller 36 is in communication with the control circuitry 30 and instructs the control circuitry 30 to control the supply of power from the power source 24 to the aerosol generating device 18 or to stop the supply of power from the power source 24 to the aerosol generating device 18. The device controller 36 may also receive data generated by the smoke puff sensor 32 via the control circuitry 30.

[0098] The charging connector 38 is located at a second end of the aerosol generating device 10 and is electrically connected to the second circuit board 34. The charging connector 38 is configured to receive a supply of power from an external device, such as a mains charger or a universal serial bus (USB) charger. The device controller 36 controls the supply of power received by the charging connector 38 to recharge the power source 24.

[0099] Two feedback devices, including a light emitting diode (LED) module 40 and a vibration motor 42, are electrically connected to the second circuit board 34. The device controller 36 is configured to provide feedback to the user using the two feedback devices. For example, the device controller 36 may control the LED module 40 to provide the user with the status of the power source 24. The device controller 36 may control the vibration motor 42 to indicate at least one of the start of a heating cycle and the end of a heating cycle.

[0100] A user input device comprising a push button 44 is electrically connected to the second circuit board 34. The push button 44 allows a user to operate the aerosol generation device by providing one or more signals to the device controller 36. For example, the device controller 36 may be configured to allow a user to use a single button press or a combination of button presses to initiate a heating cycle, terminate a heating cycle, generate feedback using at least one of the LED module 40 and the vibration motor 42, and modify the configuration of the aerosol generation device 10.

[0101] 3 and 4 show top and bottom perspective views of the aerosol generation device 10 with the outer housing 16 removed to show the arrangement of the first circuit board 28 and the second circuit board 34 within the aerosol generation device 10. The first circuit board 28 resides above the second circuit board 34.

[0102] During use of the aerosol generation device 10, the electrical components provided on the first circuit board 28 and the second circuit board 34, including the control circuit 30 and the device controller 36, generate heat. To dissipate the heat generated from the first circuit board 28 and the second circuit board 34 and to prevent thermal damage to the control circuit 30 and the device controller 36, the aerosol generation device includes a thermally conductive assembly 46. The incorporation of the thermally conductive assembly 46 into the aerosol generation device 10 is shown in Figures 3 and 4. The thermally conductive assembly 46 is shown in greater detail separated from the aerosol generation device 10 in Figure 5.

[0103] The thermally conductive assembly 46 has a first end 48 positioned between the first circuit board 28 and the second circuit board 34 and a second end 50 spaced apart from the first circuit board 28 and the second circuit board 34.

[0104] A second end 50 of the thermally conductive assembly 46 is defined by a thermally conductive frame 52 disposed to partially surround the power source 24 to provide thermal contact between the second end 50 of the thermally conductive assembly 46 and the power source 24. In the assembled aerosol generating article 10 shown in FIG. 3, the thermally conductive frame 52 is partially embedded within the inner housing 12 by overmolding a portion of the inner housing 12 onto the outside of the thermally conductive frame 52 during manufacture of the aerosol generating device 10.

[0105] The first end 48 of the thermally conductive assembly 46 includes a first transverse member 54, a first longitudinal arm 56 extending between the first transverse member 54 and the thermally conductive frame 52, a second transverse member 58, and a second longitudinal arm 60 extending between the second transverse member 58 and the thermally conductive frame 52.

[0106] The first and second cross members 54, 58 are positioned within slots defined by the first and second circuit boards 28, 34 to provide thermal contact between the first end 48 of the thermally conductive assembly 46 and each of the first and second circuit boards 28, 34. The first cross member 54 includes a first portion 62 positioned within a first slot 64 defined by the first circuit board 28. The second cross member 58 includes a second portion 66 positioned within a second slot 68 defined by the first circuit board 28. The second cross member 58 also includes a third portion 70 positioned within a third slot 72 defined by the second circuit board 34.

[0107] The thermal contact between the first and second cross members 54, 58 and the first and second circuit boards 28, 34 facilitates the transfer of heat from the first and second circuit boards 28, 34 to the first end 48 of the thermally conductive assembly 46. The heat transferred to the first end 48 of the thermally conductive assembly 46 is conducted along the first and second longitudinal arms 56, 60 to the thermally conductive frame 52 where it is dissipated to the power supply 24 and the inner housing 12. The thermal contact between the first and second cross members 54, 58 and the first circuit board 28 provides a higher rate of heat transfer than thermal contact between only the second circuit board 34 and the second cross member 58. The higher rate of heat transfer accommodates a higher rate of heat generation by the control circuitry 30 compared to the device controller 36.

[0108] Figure 6 illustrates an alternative arrangement of the thermally conductive frame 52 with respect to the inner housing 12. In the embodiment illustrated in Figure 6, the thermally conductive frame 52 is entirely above the inner housing 12 and the power source 24. In other words, the thermally conductive frame 52 is not partially embedded within the inner housing 12. This arrangement simplifies assembly of the aerosol generating device 10 as it does not require overmolding the inner housing 12 over the thermally conductive frame 52, however, the rate of heat transfer from the thermally conductive frame 52 to the inner housing 12 may be reduced.

[0109] Figure 7 shows an aerosol generation device 100 according to a second embodiment of the present invention. The aerosol generation device 100 is substantially similar to the aerosol generation device of Figure 1, and like reference numbers have been used to designate like parts.

[0110] The aerosol generating device 100 differs from the aerosol generating device 10 by the presence of an aerosol generator. Although the aerosol generating device 100 includes an aerosol generator 118 comprising an inductor coil 20, the aerosol generating device 118 also comprises a susceptor element 222 extending into the cavity 14. During use, an aerosol-forming substrate is inserted into the cavity 14 such that the susceptor element 222 is received within the aerosol-forming substrate.

[0111] The remainder of the aerosol generation device 100, including the thermally conductive assembly 46, is identical to the aerosol generation device 10 of FIG.

[0112] Figure 8 shows an aerosol generation device 200 according to a third embodiment of the present invention. The aerosol generation device 200 is substantially similar to the aerosol generation device of Figure 1, and like reference numbers have been used to designate like parts.

[0113] The aerosol generating device 200 differs from the aerosol generating device 10 by the presence of an aerosol generator. Instead of an inductor coil, the aerosol generator 218 of the aerosol generating device 200 comprises an electric heater 220 comprising a resistive heating element that extends into the cavity 14. During use, the aerosol-forming substrate is inserted into the cavity 14 such that the electric heater 220 is received within the aerosol-forming substrate.

[0114] The remainder of the aerosol generation device 200, including the thermally conductive assembly 46, is identical to the aerosol generation device 10 of FIG.

Claims

1. An aerosol generating device, comprising: an aerosol generator for generating an aerosol from an aerosol-forming substrate; Power supply, a circuit board including a control circuit for controlling the supply of power from the power source to the aerosol generator; a thermally conductive assembly having a first end in thermal contact with the circuit board and a second end spaced from the circuit board; the circuit board is a first circuit board, the aerosol generating device further comprises a second circuit board, and the first end of the thermally conductive assembly is in thermal contact with the second circuit board; and An aerosol generating device, wherein the second circuit board is at least partially on the first circuit board, the second circuit board is spaced apart from the first circuit board, and the first end of the thermally conductive assembly is positioned between the first circuit board and the second circuit board.

2. 2. The aerosol generating device of claim 1, wherein the second end of the thermally conductive assembly is in thermal contact with the power source.

3. 3. The aerosol generating device of claim 1 or claim 2, wherein the thermally conductive assembly comprises a thermally conductive frame defining the second end of the thermally conductive assembly, and the power source is positioned at least partially within the thermally conductive frame.

4. An aerosol generating device as described in any one of claims 1 to 3, wherein the thermally conductive assembly has at least one transverse member at the first end of the thermally conductive assembly, and a portion of the at least one transverse member is positioned within a slot defined by the circuit board.

5. 5. An aerosol generating device according to claim 4, which is based on claim 3, wherein the thermally conductive assembly comprises at least one longitudinal arm extending between the at least one transverse member and the thermally conductive frame.

6. An aerosol generating device as described in claim 4 or claim 5, wherein the slot defined by the circuit board is a first slot, the circuit board further defines a second slot, the at least one transverse member comprises a first transverse member having a first portion positioned in the first slot, and the at least one transverse member further comprises a second transverse member having a second portion positioned in the second slot.

7. An aerosol generating device according to any one of claims 4 to 6, wherein at least a portion of the at least one transverse member is positioned within a slot defined by the second circuit board.

8. 7. The aerosol generating device of claim 6, wherein the second circuit board defines a third slot, and the second transverse member has a third portion positioned within the third slot.

9. 9. The aerosol generating device of claim 8, wherein the first transverse member is in thermal contact only with the first circuit board.

10. The aerosol generating device of any one of claims 1 to 9, wherein the aerosol generating device comprises at least one additional electrical component, the at least one additional electrical component comprising at least one of a charging connector, a user input device, and a feedback device, and the at least one additional electrical component is electrically connected to the second circuit board.

11. The aerosol generating device of any one of claims 1 to 10, wherein the aerosol generating device comprises an inner housing, the power source is positioned within the inner housing, and a portion of the inner housing is overmolded outside at least a portion of the second end of the thermally conductive assembly.

12. The aerosol generating device of any one of claims 1 to 11, wherein the aerosol generating device comprises an inner housing, the power source is positioned within the inner housing, and at least a portion of the second end of the thermally conductive assembly is above a portion of the inner housing.

13. 13. An aerosol generating device according to any one of the preceding claims, wherein the aerosol generator comprises an inductive heating arrangement.

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