Aerosol-generating device having heat conductive assembly

Abstract

To provide an aerosol-generating device comprising an aerosol generator and a control circuit that facilitates the dissipation of excess heat generated by the control circuit.SOLUTION: There is provided an aerosol-generating device (10) comprising an aerosol generator (18) for generating an aerosol from an aerosol-forming substrate, a power supply (24), and a circuit board (28) comprising a control circuit (30) for controlling a supply of power from the power supply (24) to the aerosol generator (18). The aerosol-generating device (10) also comprises a heat conductive assembly (46) comprising a first end (48) in thermal contact with the circuit board (28) and a second end (50) spaced apart from the circuit board (28).SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to an aerosol generating device comprising a thermally conductive assembly.

Background Art

[0002] Aerosol generation systems in which an aerosol-forming substrate, such as a tobacco-containing substrate, is heated rather than burned are well known in the art. The purpose of such aerosol generation 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 generation systems, an aerosol is generated by the transfer of energy from an aerosol generator of the aerosol generating device to an aerosol-forming substrate or material in an aerosol-generating article that is physically separated 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 within, 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 entrained in the air drawn through the aerosol-generating article. The released compounds condense as they cool to form an aerosol that can be inhaled by the consumer.

Summary of the Invention

Problems to be Solved by the Invention

[0003] During use of such aerosol generating devices, a control circuit 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 circuit. However, the small size of typical aerosol generating devices that involves the need for the user to hold the device during use makes such dissipation of excess heat difficult.

[0004] It will be possible to describe providing an aerosol generator and a control circuit that facilitates dissipation of excessive heat generated by the control circuit.

Means for Solving the Problems

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

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

[0007] Preferably, the circuit board and the power source are arranged for conductive heat transfer from the circuit board to the power source.

[0008] The circuit board may be in direct contact with the power source. Advantageously, the 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 supply may be arranged for indirect conductive heat transfer from the circuit board to the power supply. 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 supply by means of at least one additional element. Advantageously, the at least one additional element may facilitate the desired orientation and position of the circuit board relative to the power supply while providing conductive heat transfer from the circuit board to the power supply. The desired orientation and position of the circuit board relative to the power supply may be adapted to at least one of the desired size and the desired shape of the aerosol generating device.

[0010] The at least one additional element may include 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.

[0011] According to the present disclosure, an aerosol generating device is provided. 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 a control circuit. The control circuit may be for controlling the supply of power from the power supply 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 supply, and a circuit board comprising a control circuit for controlling the supply of power from the power supply 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 apart from the circuit board.

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

[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] As used herein, the term "aerosol-forming substrate" refers to a substrate having the ability to release a volatile compound 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] As used herein, the term "aerosol-generating article" refers to an article comprising an aerosol-forming substrate having the ability to release 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 who sucks or puffs on a mouthpiece at the proximal end or user side of the system. The aerosol-generating article may be disposable. An article comprising an aerosol-forming substrate containing tobacco may be referred to as a tobacco stick.

[0017] As used herein, the term "aerosol generating system" refers to a 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 cooperate to generate an aerosol.

[0018] Preferably, the second end of the thermally conductive assembly is in thermal contact with a power source.

[0019] Advantageously, there may be a high thermal gradient between the circuit board and the power source during use. Advantageously, the high thermal gradient and thermal contact between the second end of the thermally conductive assembly and the power source 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 source may facilitate the use of the aerosol generating device at a cold ambient temperature. For example, at temperatures of about 5 degrees Celsius or less, the performance of some power sources may degrade. Thus, transferring heat from the circuit board to the power source may advantageously raise the temperature of the power source above the ambient temperature. Advantageously, raising the temperature of the power source above the ambient temperature may maintain or improve the performance of the power source.

[0021] The thermally conductive assembly preferably comprises a thermally conductive frame that defines the second end of the thermally conductive assembly. The power source is preferably positioned at least partially within the thermally conductive frame.

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

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

[0024] An aerosol generating device according to 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 at least one transverse member positioned within a slot defined by a circuit board to a thermally conductive assembly may facilitate thermal contact between the circuit board and a first end of the thermally conductive assembly.

[0026] Advantageously, providing at least one transverse member positioned within a slot defined by a circuit board to a thermally conductive assembly may serve to maintain the first end of the thermally conductive assembly in a state of thermal contact with the circuit board. Advantageously, the combination of at least one transverse member and the slot may obviate the need to solder or adhere the first end of the thermally conductive assembly to the circuit board. Advantageously, obviating the need to solder or adhere 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 at least one transverse member positioned within a slot defined by a circuit board to a thermally conductive assembly may facilitate the positioning of the circuit board and the thermally conductive assembly relative to each other during the assembly of the aerosol generating device.

[0028] Preferably, the at least one transverse member is received within 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 within 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, and each of the transverse members is 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 a control circuit 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 a plurality of transverse members may further facilitate positioning of the circuit board and the thermally conductive assembly relative to each other during assembly of the aerosol generating device.

[0033] The slot defined by the circuit board may be a first slot, and the circuit board defines a second slot. At least one transverse member may comprise a first transverse member having a first portion positioned within the first slot and a second transverse member having a second portion positioned within the second slot.

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

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

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

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

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

[0039] In embodiments where 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 extends between one of the transverse members and the thermally conductive frame.

[0040] In embodiments where 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 generator 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 an aerosol generator having a shorter length compared to an aerosol generator comprising 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 generator. 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 on top of the first circuit board. Advantageously, being at least partially on 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.

[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] The 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 a conductive path.

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

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

[0050] The aerosol generating device preferably comprises a device controller configured to control the operation of the aerosol generating device. The device controller is preferably provided on the 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 supply. The device controller is preferably in electrical communication with a control circuit to control the supply of power from the power supply 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 the control circuit to control the supply of power from the power supply to the aerosol generator.

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

[0052] In an embodiment where at least one transverse member comprises a plurality of transverse members, at least one of the transverse members may be received within a slot defined by a first circuit board and within a slot defined by a second circuit board. At least one of the transverse members may comprise a first end received within a slot defined by the first circuit board and a second end received within a slot defined by the second circuit board.

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

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

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

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

[0057] Suitable heat-conductive materials may include metals. The heat-conductive assembly may be a metal. Suitable metals include aluminum, copper, iron, gold, zinc, or any suitable alloy 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 heat-conductive assembly is preferably formed from brass. Advantageously, brass may be malleable enough to facilitate the formation of a heat-conductive assembly having the required shape. Advantageously, a heat-conductive assembly formed from brass may be elastic enough to facilitate the retention of one or more components of the aerosol generating device by the heat-conductive assembly. For example, in an embodiment where the heat-conductive assembly comprises a heat-conductive frame, the brass heat-conductive assembly may be elastic enough to facilitate the retention of a power source within the heat-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 fixed to the inner housing. The circuit board may be fixed to the housing by an interference fit between a portion of the circuit board and the inner housing. In an embodiment where 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 fixed to the inner housing.

[0061] The power source is preferably positioned 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 the dissipation of heat from the circuit board to the inner housing by the thermally conductive assembly.

[0063] In an embodiment where 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 be over the portion of the inner housing.

[0065] A portion of the inner housing is preferably overmolded outside at least a portion of the second end of the thermally conductive assembly. Advantageously, overmolding a portion of the inner housing outside 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 an embodiment where the second end of the thermally conductive assembly comprises a thermally conductive frame, a portion of the inner housing is preferably overmolded outside at least a portion of the thermally conductive frame.

[0067] The inner housing is preferably formed from a material suitable for molding on 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 from 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), a blend 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 circuit for controlling the supply of power from the power source to the aerosol generator may comprise at least one of a microprocessor, a microcontroller, and an application specific integrated circuit (ASIC).

[0069] In embodiments where the aerosol generating device comprises a device controller, the device controller may include at least one of a microprocessor, a microcontroller, and an application specific integrated circuit (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 (such as a lithium cobalt, lithium iron phosphate, or lithium polymer battery). The power source may also be another form of charge storage device such as a capacitor. The power source may need to be recharged and may also have a capacity that allows for sufficient energy storage for one or more user operations, such as one or more experiences of aerosol generation. For example, the power source may have a capacity sufficient to enable continuous heating of the aerosol-forming substrate for about 6 minutes, or a multiple of 6 minutes, corresponding to the typical time taken to smoke one conventional cigarette. In another example, the power source may have a capacity sufficient to enable a predetermined number of smoking sessions or discontinuous activation of the heater.

[0071] The aerosol generating device preferably comprises a cavity for receiving the aerosol-forming substrate. In embodiments where 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 where 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 composite materials containing at least one of metals, alloys, and plastics. Suitable materials include thermoplastic resins suitable for food or pharmaceutical applications. Suitable thermoplastic resins include polypropylene, polyetheretherketone (PEEK), and polyethylene.

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

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

[0076] The electric heater may include 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 at least one form of a blade, a pin, and a cone. The internal heating element is preferably configured to be insertable into the aerosol-forming substrate. In an embodiment where the aerosol generator includes a cavity for receiving the aerosol-forming substrate, at least one internal heating element preferably extends into the cavity.

[0077] The electric heater may include 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. At least one external heating element is preferably configured to at least partially surround the aerosol-forming substrate received by the aerosol generator. In an embodiment where the aerosol generator includes a cavity for receiving the aerosol-forming substrate, at least one external heating element preferably at least partially surrounds the cavity.

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

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

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

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

[0082] The aerosol generator may include an induction heating arrangement. The induction heating arrangement may include 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 of 500 kilohertz to 30 megahertz. The aerosol generating device may include a DC / AC inverter for converting the DC current supplied by a DC power source into an oscillating current. The inductor coil may be arranged to generate a high-frequency oscillating electromagnetic field when receiving the high-frequency oscillating current from the power source. The inductor coil may be arranged to generate a high-frequency oscillating electromagnetic field within a device cavity configured to receive the aerosol-forming substrate. In embodiments where the aerosol generating device includes a cavity for receiving the aerosol-forming substrate, the inductor coil may substantially surround the cavity. The inductor coil may at least partially extend along the length of the cavity.

[0083] In an embodiment 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 that includes a material having the ability to convert electromagnetic energy into heat. When the susceptor element is located within an 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 an embodiment where the aerosol generating device comprises a cavity for receiving an aerosol-forming substrate, when the aerosol-forming substrate is received within the cavity, the oscillating electromagnetic field generated by the inductor coil may induce a current within the susceptor element, and the susceptor element may be arranged 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 a plurality of 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 volatile compounds 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 composite materials of metallic materials. The susceptor element may comprise ferromagnetic alloys such as, for example, ferrite iron, ferromagnetic steel or stainless steel, ferromagnetic particles, and ferromagnetic materials such as ferrite.

[0085] In an embodiment where the aerosol generator has an induction 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 that includes an aerosol forming substrate and at least one susceptor element. During 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 oscillate when powered from a 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 at least one nozzle. The aerosol generating device may comprise a mesh, and the mesh may define at least one nozzle.

[0087] The mesh may be arranged to oscillate during use of the aerosol generating device. The oscillating 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 oscillate the mesh during use.

[0088] The mesh may be arranged to remain substantially stationary relative to the oscillating piezoelectric element during use of the aerosol generating device. The 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 the liquid aerosol forming substrate.

[0089] Embodiments of the present invention will be described below, by way of illustration only and with reference to the accompanying drawings.

Brief Description of the Drawings

[0090]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

[0091] Figure 1 shows a schematic cross-sectional view of an aerosol generating device 10 according to a first embodiment of the present invention. The aerosol generating device 10 comprises an inner housing 12 defining a cavity 14 for receiving an aerosol forming substrate at a first end of the aerosol generating device 10. The aerosol generating 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 having an induction heating arrangement. The induction heating arrangement comprises an inductor coil 20 surrounding the cavity 14. During use, an aerosol forming article comprising an aerosol forming substrate and a susceptor element is inserted into the cavity 14.

[0093] The power supply 24 is positioned at the second end of the aerosol generator 10 within the inner housing 12. The power supply 24 is a rechargeable battery.

[0094] The aerosol generator 10 also includes several control components roughly illustrated by the box 26 in FIG. 1. The control components and their functional connectivity to each other (illustrated by the connection arrows) are shown in more detail in the schematic diagram of FIG. 2.

[0095] The aerosol generator 10 includes a first circuit board 28 provided with a control circuit 30. The control circuit 30 is configured to control the supply of power from the power supply 24 to the aerosol generator 18. In particular, the control circuit 30 includes a DC / AC inverter to convert the supply of DC power from the power supply 24 into an oscillating current supplied to the inductor coil 20. During 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 the susceptor element of the aerosol-generating article received within the cavity 14, which heats the aerosol-forming substrate of the aerosol-generating article.

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

[0097] The aerosol generating device 10 also includes a second circuit board 34 provided with a device controller 36. The device controller 36 communicates with the control circuit 30 to instruct the control circuit 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 smoking sensor 32 via the control circuit 30.

[0098] The charging connector 38 is positioned at the 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 power supply from an external device such as a main 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 and the end of the heating cycle.

[0100] The user input device with the push button 44 is electrically connected to the second circuit board 34. The push button 44 enables the user to operate the aerosol generating device by providing one or more signals to the device controller 36. For example, the device controller 36 may be configured to allow the user to start a heating cycle, end 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 generating device 10 by using a single button press or a combination of button presses.

[0101] Figures 3 and 4 show a top perspective view and a bottom perspective view of the aerosol generating 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 generating device 10. The first circuit board 28 is on top of the second circuit board 34.

[0102] During use of the aerosol generating 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 generating device includes a thermally conductive assembly 46. The incorporation of the thermally conductive assembly 46 into the aerosol generating device 10 is shown in Figures 3 and 4. The thermally conductive assembly 46 is shown in detail separated from the aerosol generating device 10 of Figure 5.

[0103] The thermally conductive assembly 46 includes 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] The 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 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 transverse member 54 and the second transverse member 58 are positioned within slots defined by the first circuit board 28 and the second circuit board 34 to provide thermal contact between the first end 48 of the thermally conductive assembly 46 and each of the first circuit board 28 and the second circuit board 34. The first transverse member 54 includes a first portion 62 positioned within a first slot 64 defined by the first circuit board 28. The second transverse member 58 includes a second portion 66 positioned within a second slot 68 defined by the first circuit board 28. The second transverse 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 transverse member 54 and the second transverse member 58 and the first circuit board 28 and the second circuit board 34 facilitates the transfer of heat from the first circuit board 28 and the second circuit board 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 longitudinal arm 56 and the second longitudinal arm 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 transverse member 54 and the second transverse member 58 and the first circuit board 28 provides a higher heat transfer rate than the thermal contact only between the second circuit board 34 and the second transverse member 58. The higher heat transfer rate accommodates the higher heat generation rate by the control circuit 30 compared to the device controller 36.

[0108] FIG. 6 shows an alternative arrangement of the thermally conductive frame 52 with respect to the inner housing 12. In the embodiment shown in FIG. 6, the thermally conductive frame 52 is generally over the inner housing 12 and the power supply 24. In other words, the thermally conductive frame 52 is not partially embedded within the inner housing 12. This arrangement simplifies the assembly of the aerosol generating device 10 as it does not require overmolding the inner housing 12 over the outside of the thermally conductive frame 52, but the heat transfer rate from the thermally conductive frame 52 to the inner housing 12 may be reduced.

[0109] FIG. 7 shows an aerosol generating device 100 according to a second embodiment of the present invention. The aerosol generating device 100 is substantially the same as the aerosol generating device of FIG. 1, and like reference numerals are used to designate like parts.

[0110] The aerosol generating device 100 is different from the aerosol generating device 10 by virtue of having an aerosol generator. The aerosol generating device 100 includes an aerosol generator 118 having an inductor coil 20, and the aerosol generator 118 also includes a susceptor element 222 extending into the cavity 14. During use, the aerosol forming substrate is inserted into the cavity 14, whereby the susceptor element 222 is received within the aerosol forming substrate.

[0111] The remainder of the aerosol generating device 100, including the thermally conductive assembly 46, is identical to the aerosol generating device 10 of FIG. 1.

[0112] FIG. 8 shows an aerosol generating device 200 according to a third embodiment of the present invention. The aerosol generating device 200 is substantially the same as the aerosol generating device of FIG. 1, and like reference numerals are used to designate like parts.

[0113] The aerosol generating device 200 is different from the aerosol generating device 10 by virtue of having an aerosol generator. Instead of an inductor coil, the aerosol generator 218 of the aerosol generating device 200 includes an electric heater 220 having a resistive heating element extending into the cavity 14. During use, the aerosol forming substrate is inserted into the cavity 14, whereby the electric heater 220 is received within the aerosol forming substrate.

[0114] The remainder of the aerosol generating device 200, including the thermally conductive assembly 46, is identical to the aerosol generating device 10 of FIG. 1.

[0115] 1. An aerosol generating device, comprising: an aerosol generator for generating an aerosol from an aerosol forming substrate; a power source; a circuit board comprising 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 apart from the circuit board. The circuit board is the first circuit board, the aerosol generator further includes a second circuit board, and the first end of the thermally conductive assembly is in thermal contact with the second circuit board, and The second circuit board is at least partially on top of 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, an aerosol generator. 2. The aerosol generator according to 1, wherein the second end of the thermally conductive assembly is in thermal contact with the power source. 3. The aerosol generator according to 1 or 2, wherein the thermally conductive assembly includes a thermally conductive frame defining the second end of the thermally conductive assembly, and the power source is at least partially positioned within the thermally conductive frame. 4. The aerosol generator according to any one of 1 to 3, wherein the thermally conductive assembly includes 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. The aerosol generator according to the combination of 3 and 4, wherein the thermally conductive assembly includes at least one longitudinal arm extending between the at least one transverse member and the thermally conductive frame. 6. 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 includes a first transverse member having a first portion positioned within the first slot, and the at least one transverse member further includes a second transverse member having a second portion positioned within the second slot, the aerosol generator according to 4 or 5. 7. The aerosol generator according to 3, wherein at least a portion of the at least one transverse member is positioned within a slot defined by the second circuit board. 8. The aerosol generating device according to 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. The aerosol generating device according to claim 8, wherein the first transverse member is in thermal contact only with the first circuit board. 10. The aerosol generating device according to 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 comprises 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 according to 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 part of the second end of the thermally conductive assembly. 12. The aerosol generating device according to 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 part of the second end of the thermally conductive assembly is on a portion of the inner housing. 13. The aerosol generating device according to any one of claims 1 to 12, wherein the aerosol generator comprises an induction heating arrangement.

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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