An aerosol generating device

Abstract

An aerosol generating device is described. The aerosol generating device includes a heater assembly, a power source, a printed circuit board assembly (16), and a wireless charging assembly (20). The printed circuit board assembly (16) includes a controller adapted to control operation of the aerosol generating device, and a printed circuit board (18) having a main surface on which the controller is mounted. The wireless charging assembly (20) includes an electrically conductive receiving coil (22) for wireless inductive charging, and a planar shielding member (24) having a main surface (24a) on which the receiving coil (22) is mounted. The wireless charging assembly (16) is arranged substantially perpendicular to the printed circuit board (18).

Description

[0001] AN AEROSOL GENERATING DEVICE

[0002] Technical Field

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

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

[0005] Technical Background

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

[0007] The aerosol generating material may be a solid or liquid. For example, the aerosol generating article may include a solid or semi-solid substrate of plant derived material, such as tobacco, or it may include a wick and a heater to produce vapour from aerosol generating liquid stored in a capsule or tank. When a user operates the aerosol generating device, liquid that has soaked into the wick is heated by the heater, producing a vapour which cools and condenses to form an aerosol which may then be inhaled. An aerosol generating article (sometimes called a pod or cartridge) may be received in the aerosol generating device and may include a liquid store, a liquid transfer element (e.g., a wick) and a heater. Electrical contacts may provide an electrical connection between the heater and an energy storage device of the aerosol generating device. The energy storage device may be a rechargeable battery that may be charged from an external power source by a charging assembly of the energy storage device assembly. A stick that looks like an ordinary cigarette may also be used as an aerosol generating article.

[0008] The charging assembly may include an inductive receiving coil suitable for wireless charging of the battery. In particular, a wireless external power source such as a wireless charger will include an inductive transmitting coil that creates an electromagnetic field when an electric current flows through it. The inductive transmitting coil and the inductive receiving coil may also be referred to as a primary coil and a secondary coil, respectively. When the receiving coil of the charging assembly of the aerosol generating device is in close proximity with the wireless charger, the electromagnetic field generates an electric current in the receiving coil of the charging assembly that may be provided to a charging circuit and used to charge the battery. Wireless charging is a convenient way to charge the battery without having to physically and / or mechanically connect a charging cable to the aerosol generating device. New ingress protection standards may also mean that wired charging assemblies, e.g., those that might include a plug socket such as a universal serial bus (USB) socket (receptacle) for receiving a USB charging cable (plug), and which therefore also require an opening in the housing, may no longer be suitable for use in aerosol generating devices. Using wireless charging may also avoid the need for a user to carry or use a separate charging cable.

[0009] An aerosol generating device that uses wireless charging typically has more internal components (e.g., the wireless charging assembly) than an aerosol generating device that is not compatible with wireless charging. An aerosol generating device is typically a portable (hand-held) device so its size and weight may be limited. It may therefore be difficult to accommodate these additional internal components within the housing of the aerosol generating device. The lack of internal space within the housing may also make it more difficult to protect sensitive electronic components from the electromagnetic field generated during wireless charging.

[0010] There may be a limit on the size of the receiving coil that can be positioned within the housing of the aerosol generating device and high electric currents may need to be generated in order to meet expected charging times. This may result in excessive heat being generated by the receiving coil and related components during charging. The heat that is generated should not be fully dissipated into the housing to improve device safety. The housing will normally be made of a plastics material because an electrically conductive material cannot be positioned between the receiving coil of the charging assembly and the transmitting coil of the external wireless charger if a wireless connection between the receiving and transmitting coils is to be established. This may make dissipating all of the generated heat in the housing even more difficult because the thermal conductivity and thermal capacity of plastics materials are generally lower than the thermal conductivity and thermal capacity of electrically conductive materials such as metals, for example. Generating excessive heat within the housing may accelerate degradation of other internal components of the aerosol generating device, including the battery. There is therefore a need for an improved aerosol generating device where preferably at least part of the generated heat during wireless charging is removed by heat exchange with cooling air flowing through one or more air paths of a heat exchanger. There is also a need for an improved aerosol generating device that overcomes the other issues mentioned above, and where the aerosol generating device is designed specifically for wireless charging of a battery or other power source using a wireless charging assembly that is positioned within a housing of the aerosol generating device. In particular, there is a need for an improved aerosol generating device that has a mechanical structure that is suitable for wireless charging.

[0011] Summary of the Disclosure

[0012] According to a first aspect of the present disclosure, there is provided an aerosol generating device comprising: a heater assembly comprising: a heating chamber adapted to receive an aerosol generating article; and a heater adapted to heat the aerosol generating article when received in the heating chamber; a power source (e.g., an energy storage device such as a rechargeable Li-ion secondary battery) adapted to supply power to the heater; a printed circuit board assembly (or PCBA) comprising: a controller (e.g., a microcontroller unit (or MCU)) adapted to control operation of the aerosol generating device; and a printed circuit board having a main surface on which the controller is mounted; and a wireless charging assembly comprising: an electrically conductive receiving coil for wireless inductive charging (e.g., for wirelessly charging the energy storage device or other power source); and a planar first shielding member having a main surface on which the receiving coil is mounted such that the receiving coil is at least partially covered by the first shielding member; wherein the wireless charging assembly is arranged substantially perpendicular to the printed circuit board.

[0013] The first shielding member has a planar construction, e.g., may be formed as a sheet. The first shielding member may be a ferrite sheet or a sheet of ferrite-containing material, for example. It will be understood that ferrite is typically an iron-oxide containing magnetic ceramic material. The first shielding member is designed to shield components of the aerosol generating device from the electromagnetic field that is generated by an inductive transmitting coil of an external wireless charger, for example, during wireless charging. The receiving coil must be exposed to the electromagnetic field and the magnetic flux must extend into the receiving coil so that the electromagnetic field generates an electric current in the receiving coil and it may be mounted on (or positioned adjacent) an outer main surface of the first shielding member - i.e., between the first shielding member and an outer housing of the aerosol generating device. The outer main surface of the first shielding member may be substantially perpendicular to a main surface of the printed circuit board. The receiving coil is preferably positioned very close to, or in contact with, the facing part of the housing. The position of the receiving coil may be indicated by a visual indicator (e.g., a wireless charging logo) at a corresponding position on the outer surface of the housing. The heater assembly, power source etc. may be positioned on the other side of the first shielding member - i.e., where the first shielding member has an inner main surface that faces towards the interior of the housing. The first shielding member is preferably larger than the receiving coil so that the receiving coil is completely covered by the first shielding member. This provides increased protection against the electromagnetic field generated during wireless charging, particularly for the components such as the heater assembly, power source etc. that are located on the other side of the first shielding member.

[0014] The receiving coil preferably comprises a plurality of turns arranged substantially in a common plane. In other words, the receiving coil also preferably has a planar construction so that the wireless charging assembly as a whole is therefore substantially planar. In one arrangement, the receiving coil may be formed of wire having an outer diameter of about 4.0 mm (26AWG) and have between about 10 and about 14 turns. The receiving coil may be about 11 mm wide, about 43 mm long, and about 4 mm deep. The receiving coil may have the following parameters:

[0015] - nominal operating voltage: 10.02 V

[0016] - full battery charging time: about 101 min @ 2.2 A

[0017] - charging time for one vaping session: about 5 mins @ 2.1 A

[0018] - reverse wireless charging time for one vaping session: about 7 mins @ 2.2 A.

[0019] The receiving coil may be adhered to the outer main surface of the first shielding member using a thermal adhesive or tape, for example. However, the receiving coil does not necessarily have to be physically adhered to the first shielding member and may simply be positioned adjacent to the outer surface of the first shielding member in some arrangements. Even if the receiving coil is not physically adhered to the first shielding member, the receiving coil and the first shielding member are preferably in good thermal contact. Arranging the wireless charging assembly, and in particular, the receiving coil, to be substantially perpendicular to the printed circuit board means that any electronic components such as the controller that are mounted on the main surface of the printed circuit board are better protected from any negative effects that may be caused by exposure to the generated electromagnetic field during wireless charging. In particular, such an arrangement may make it more difficult for magnetic flux to penetrate the electronic components as compared to an arrangement where the printed circuit board is arranged substantially parallel to the wireless charging assembly, for example.

[0020] The aerosol generating device may further comprise a housing that forms at least part of the exterior of the aerosol generating device. The housing may have a substantially elliptical or rectangular cross section. The wireless charging assembly may be positioned adjacent a main surface of the housing. The wireless charging assembly is optionally connected to the main surface of the housing.

[0021] The printed circuit board may be spaced apart from the wireless charging assembly in a direction that is parallel to the normal of the main surface of the printed circuit board. In other words, when viewed along a longitudinal axis of the aerosol generating device that is substantially perpendicular to both the normal of the main surface of the printed circuit board and the normal of the main surface of the first shielding member (i.e., where the longitudinal axis and the normals define a mutually orthogonal coordinate system for the aerosol generating device), the printed circuit board may be spaced apart from the wireless charging assembly along a transverse axis that is parallel with the normal of the main surface of the printed circuit board. The printed circuit board may also be spaced apart from the wireless charging assembly along a lateral axis that is parallel with the normal of the main surface of the wireless charging assembly. The printed circuit board may partially overlap with the wireless charging assembly along the longitudinal axis. Such an arrangement may better protect the electronic components mounted on the printed circuit board from any negative effects that may be caused by exposure to the generated electromagnetic field during wireless charging. Arranging the printed circuit board and the wireless charging assembly in this way may be preferable to trying to provide additional protection against the generated electromagnetic field by increasing the size of the first shielding member, for example. Because the material used to form the first shielding member is typically heavy (e.g., a ferrite or ferrite-containing material), increasing its size, or alternatively including lots of additional shielding members within the housing, may not be suitable because it will significantly increase the weight of the aerosol generating device.

[0022] A second shielding member may be positioned adjacent the printed circuit board. The second shielding member may be a ferrite sheet or a sheet of ferrite-containing material, for example. The second shielding member will normally be significantly smaller than the first shielding member and will therefore not significantly increase the weight of the aerosol generating device. The second shielding member may extend along an edge of the printed circuit board, e.g., the edge that is closest to the wireless charging assembly. The second shielding member may extend along substantially the full length of the edge of the printed circuit board, and may extend generally into the gap or space between the edge of the printed circuit board and a facing edge of the wireless charging assembly, e.g., the facing edge of the first shielding member. The second shielding member provides yet further protection for the electronic components mounted on the printed circuit board that are known to be particularly sensitive to the negative effects of the electromagnetic field. Including the second shielding member may therefore be particularly beneficial even though it does increase the number of shielding members within the housing of the aerosol generating device.

[0023] The aerosol generating device may further comprise a cover. The cover may be removably connected to the housing. The cover may cover part of the housing and may form at least part of the exterior of the aerosol generating device. The cover may extend around, or may overlap with, the printed circuit board. Depending on the material from which the cover is formed, it may also protect the electronic components mounted on the printed circuit board from any negative effects that may be caused by exposure to the generated electromagnetic field during wireless charging. It will be understood that to provide beneficial shielding, the cover material preferably has a relative magnetic permeability (i.e., p / po) greater than 1 and that the cover may optionally comprise any suitable metal or metal alloy, for example.

[0024] The printed circuit board assembly may further include a connector that is mounted to the printed circuit board. The wireless charging assembly may further comprise at least one wire electrically connected between the receiving coil and the connector - e.g., for electrically connecting the receiving coil to the printed circuit board. The end of the wire (or wires) may further comprise a connector that is compatible with the connector mounted to the printed circuit board. For example, one of the connectors may be a male-type connector and the other may be a female-type connector that can be engaged together. The female-type connector may comprise a recess for receiving part of the male-type connector (i.e., the connectors are “plug-in” connectors). The compatible connectors provide an easy way of electrically connecting the wire (or wires) to the printed circuit board during the assembly process and also allow for easy disconnection if required. The connectors may comprise cooperating locking features that temporarily lock the engaged connectors together, but which allow the engaged connectors to be released if necessary, e.g., if the receiving coil needs to be disconnected from the printed circuit board. The connector that is connected to the end of the wire (or wires) may comprise a gripping member (e.g., one or more ridges) that allows it to be gripped more easily. Using suitable plug-in connectors provides an easy and reliable way to electrically connect the wireless charging assembly to the printed circuit board. The PCBA may further comprise a charging circuit (e.g., a charging integrated circuit (IC)) that is mounted to the printed circuit board. The charging circuit may be electrically connected to the connector and the power source. The housing may further comprise an opening that corresponds to the position of the connector that is mounted to the printed circuit board. In other words, the opening of the housing is aligned with the mounted connector so that it provides access to the mounted connector from the exterior of the housing. This may help with assembling and / or disassembling the aerosol generating device. The opening may be in the part of the housing that is covered by the cover. This means that the opening is covered by the cover to prevent ingress of dust or water into the interior of the housing through the opening.

[0025] The wire (or wires) may pass through a cut-out part of the second shielding member. The cut-out part may be formed in an edge of the second shielding member, for example.

[0026] The housing may further comprise an air inlet and an air outlet. The air inlet may be covered or sealed by an air-permeable cover, e.g., by a hydrophobic membrane or similar. The air outlet may be covered or sealed by an air-permeable cover, e.g., a hydrophobic membrane or similar. The air-permeable covers will allow air to flow through the air inlet and air outlet but will prevent the ingress of water, dust etc. into the interior of the housing.

[0027] The wireless charging assembly may further comprise an air flow path fluidly connected between the air inlet and the air outlet. Heated air may flow out of the housing through the air outlet and may be replaced by cooler air (e.g., at ambient temperature) flowing in to the housing through the air inlet, for example. Cooling air may therefore flow through the air flow path in one direction from the air inlet to the downstream air outlet. The wireless charging assembly, and in particular, the first shielding member, may therefore also function as a heat exchanger so that heat that is generated during wireless charging is transferred to the cooling air and discharged outside the aerosol generating device rather than being dissipated to the housing, for example. It is for this reason that the receiving coil and the first shielding member are preferably in good thermal contact so that heat generated by the receiving coil may be transferred first to the first shielding member and then to the cooling air. The air flow path may be arranged in a longitudinal direction - i.e., may extend substantially along the direction that is parallel to the longitudinal axis of the aerosol generating device. Having the air flow path extend along the longitudinal direction may be preferred because it allows the air inlet and air outlet to be positioned at upper and lower parts of the housing where they are less likely to be covered by the hand of the user grasping the housing or body of the aerosol generating device during use. The air flow path may be defined by the first shielding member. For example, the air flow path may be formed by a channel in an inner main surface of the first shielding member - i.e., in the main surface that is opposite the outer main surface on which the receiving coil is mounted. The first shielding member may therefore provide shielding and function as a heat exchanger. The cooling of the aerosol generating device may therefore be improved without the need for an additional heat exchanger and without increasing the size and weight of the aerosol generating device. The channel that defines the air flow path may extend from a first edge to a second, opposite, edge of the first shielding member, e.g., it may extend between an upper and lower edge.

[0028] The wireless charging assembly may further comprise one or more heat exchange paths fluidly connected to the air flow path. The cooling may be further improved by transferring heat from the wireless charging assembly to the cooling air through the one or more heat exchange paths. A width of each heat exchange path may be less than a width of the air flow path. Heat exchange may therefore be improved by increasing the flow resistance of the cooling air in the one or more heat exchange paths.

[0029] Each heat exchange path may be fluidly connected to the air flow path at an acute angle relative to the direction of air flow along the air flow path, i.e., where the cooling air is flowing from the air inlet to the air outlet. This may improve the transfer of heated air from each heat exchange path to the air flow path. If each heat exchange path is connected to the air flow path at a right angle or an obtuse angle, it may be difficult for the air to flow from each heat exchange path to the air flow path and hence towards the air outlet.

[0030] Each heat exchange path may be defined by the first shielding member. For example, each heat exchange path may be formed by a channel in the inner main surface of the first shielding member. The cooling of the aerosol generating device may therefore be improved without the need for an additional heat exchanger and without increasing the size and weight of the aerosol generating device. A plurality of heat exchange paths may be formed in the inner main surface of the first shielding member and they may be formed symmetrically in a V-shaped pattern with the air flow path extending substantially along the centre of the inner main surface, for example. The apex of each V-shaped pattern may point towards the air outlet or the downstream direction of the air flow path. Each heat exchange path may extend from the air flow path to a third or fourth edge of the first shielding member, e.g., may extend to a side edge. A wireless charging assembly where the first shielding member also functions as a heat exchanger (e.g., where it comprises one or more channels that define an air flow path and optionally heat exchange paths) may be used in an aerosol generating device where the wireless charging assembly is not necessarily arranged substantially perpendicular to the printed circuit board.

[0031] The aerosol generating device may further comprise an inner frame adapted to support at least one of the heater assembly, the power source (e.g., the energy storage device) and the printed circuit board. A magnetic permeability of the inner frame may be less than a magnetic permeability of the first shielding member. Because the material used to form the shielding members is typically heavy (e.g., a ferrite or ferrite-containing material) its use may be minimised so that the weight of the aerosol generating device is kept as low as possible. The inner frame may therefore be designed without the need to protect the other components from any negative effects that may be caused by exposure to the generated electromagnetic field during wireless charging.

[0032] The wireless charging assembly may be connected to the inner frame. For example, the wireless charging assembly may be connected using one or more click-fit connectors. This arrangement may be beneficial when assembling and / or disassembling the aerosol generating device because no electrical connection is required to the housing. It means that is not necessary to consider any electrical connection when the wireless charging assembly is connected to, or removed, from the inner frame.

[0033] The aerosol generating device may further comprise a second PCBA. A connecting member may be used to electrically connect the second PCBA with the PCBA on which the controller is mounted. The connecting member may extend inside or through the inner frame. This may make it easier to assemble and / or disassemble the aerosol generating device, because such an extended connecting member will not cause an interference during the assembly or disassembly process.

[0034] The first shielding member may be moulded (i. e. , formed using moulding process) to comprise integral channels that define the air flow path and the one or more heat exchange paths. In the moulding process, a mould can be provided where the channels are defined by raised areas, e.g., in a base surface of the mould. A compound material may be poured into the mould and may be compressed, e.g., by a piston. Any suitable compound material may be used. For example, the compound material may comprise a mixture of iron, nickel, and zinc oxides. The compressed compound material may be cured or sintered to form a planar sheet with a first main surface adapted to mount the receiving coil and a second main surface with integral channels that define the air flow path and the one or more heat exchange paths.

[0035] The aerosol generating article may comprise aerosol generating material.

[0036] The aerosol generating material may comprise any type of solid or semi-solid material. Example types of aerosol generating solids include powder, granules, pellets, shreds, strands, particles, gel, strips, loose leaves, cut filler, porous material, foam material or sheets. The aerosol generating material may comprise plant derived material and in particular, may comprise tobacco. It may advantageously comprise reconstituted tobacco, for example including tobacco and any one or more of cellulose fibres, tobacco stalk fibres and inorganic fillers. The solid or semi-solid aerosol generating material may be heated by the heater of the aerosol generating aerosol generating device - e.g., when arranged in the heating chamber.

[0037] The aerosol generating material may comprise an aerosol-former. Examples of aerosol-formers include polyhydric alcohols and mixtures thereof such as glycerine or propylene glycol. Typically, the aerosol generating material may comprise an aerosolformer content of between approximately 5% and approximately 50% on a dry weight basis. In some embodiments, the aerosol generating material may comprise an aerosol-former content of between approximately 10% and approximately 22% on a dry weight basis, and possibly approximately 15% on a dry weight basis.

[0038] The aerosol generating device may be adapted to heat the aerosol generating material or substrate, without burning the aerosol generating material, to volatise at least one component of the aerosol generating material and thereby generate a heated vapour which cools and condenses to form an aerosol for inhalation by a user of the aerosol generating device. The volatile compounds released from the aerosol generating material may include nicotine or flavour compounds such as tobacco flavouring.

[0039] In general terms, a vapour is a substance in the gas phase at a temperature lower than its critical temperature, which means that the vapour may be condensed to a liquid by increasing its pressure without reducing the temperature, whereas an aerosol is a suspension of fine solid particles or liquid droplets, in air or another gas. It should, however, be noted that the terms ‘aerosol’ and ‘vapour’ may be used interchangeably in this specification, particularly with regard to the form of the inhalable medium that is generated for inhalation by a user.

[0040] When the aerosol generating material is depleted, the aerosol generating article may be removed from the aerosol generating device and a new article may be inserted.

[0041] The aerosol generating article may comprise a mouthpiece through which the generated aerosol may be inhaled.

[0042] Brief Description of the Drawings

[0043] Figure 1 is a diagrammatic view of an aerosol generating system with an aerosol generating device and an aerosol generating article;

[0044] Figure 2 is a diagrammatic view of the aerosol generating system of Figure 1 without the cover; Figure 3 is a diagrammatic view of a printed circuit board assembly (PCBA) and a wireless charging assembly of the aerosol generating device showing an outer main surface of the first shielding member of the wireless charging assembly;

[0045] Figure 4 is a diagrammatic view of the PCBA and the wireless charging assembly of Figure 3 showing an inner main surface of the first shielding member of the wireless charging assembly;

[0046] Figure 5 is a diagrammatic view of the PCBA and the wireless charging assembly of Figure 4 along a longitudinal axis of the aerosol generating device;

[0047] Figure 6 is a diagrammatic view of the PCBA and the wireless charging assembly of Figure 3 showing the outer main surface of the first shielding member of the wireless charging assembly;

[0048] Figure 7 is a diagrammatic view of the PCBA and the wireless charging assembly of Figure 3 showing the inner main surface of the first shielding member of the wireless charging assembly;

[0049] Figure 8 is a diagrammatic view of the PCBA and the wireless charging assembly of Figure 3 showing the outer main surface of the first shielding member of the wireless charging assembly;

[0050] Figure 9 is a diagrammatic view of the interior of aerosol generating device showing the PCBA and the wireless charging assembly;

[0051] Figure 10 is a diagrammatic view showing plug-fit connectors that are used to electrically connect a receiving coil of the wireless charging assembly to a printed circuit board of the PCBA;

[0052] Figure 11 is a diagrammatic view of a curved end part of the housing of the aerosol generating device; and

[0053] Figure 12 is a diagrammatic view of an inner frame of the aerosol generating device.

[0054] Detailed Description of Embodiments

[0055] Embodiments of the present disclosure will now be described by way of example only and with reference to the accompanying drawings.

[0056] Referring initially to Figure 1 there is shown diagrammatically an example of an aerosol generating system 1. The aerosol generating system 1 comprises an aerosol generating device 2 and an aerosol generating article 4 for use with the aerosol generating device 2. The aerosol generating device 2 comprises a body or housing 6 and is sized to be comfortably held by a user unaided, in a single hand.

[0057] The aerosol generating article 4 is formed as a stick that looks like an ordinary cigarette and includes aerosol generating material (not shown). The aerosol generating material may comprise plant derived material, and in particular may comprise tobacco.

[0058] The aerosol generating device 2 includes a heater assembly 8 with a heating chamber 10 that is adapted to receive the aerosol generating article 4. The heater assembly 8 also includes a heater 12 that is adapted to heat the aerosol generating article 4 when it is received in the heating chamber 10. In particular, the heater 12 will heat the aerosol generating material (not shown) to generate an aerosol for inhalation by a user.

[0059] The aerosol generating device 2 includes an energy storage device 14 in the form of a rechargeable battery for supplying power to the heater 12.

[0060] Referring to Figures 3 to 11, an electric circuit is implemented by a printed circuit board assembly (PCBA) 16. The PCBA 16 comprises electronic components that are mounted on a printed circuit board 18. The PCBA 16 is electrically connected to the energy storage device 14 of the aerosol generating device 2. The PCBA 16 includes a microcontroller unit (MCU) 19 which controls operation of the aerosol generating device 2. The MCU 19 is mounted to a main surface 18a of the printed circuit board 18. The printed circuit board 18 has an opposite main surface 18b.

[0061] Although the PCBA 16 as described herein has a single printed circuit board 18, it will be understood that a plurality of printed circuit boards may be used. In particular, if the heater assembly 8 uses an induction heating system, the PCBA 16 may include several electronic components for generating high-frequency power and it may not be possible to mount these electronic components on the single printed circuit board 18 because of the limited surface area available. The available surface area may therefore be increased by providing a plurality of printed circuit boards. Such printed circuit boards may be closely arranged using a board-to-board (B2B) connector (not shown), for example. A B2B connector would electrically connect the respective printed circuit boards of the PCBA 16 and fix their position within the aerosol generating device 2 so that they are not in contact with each other. Such an arrangement may be beneficial because a second shielding member 26 - see below - may be able to protect the plurality of closely arranged printed circuit boards of the PCBA 16, not just the printed circuit board 18.

[0062] The aerosol generating device 2 includes a wireless charging assembly 20. The wireless charging assembly 20 includes an electrically conductive receiving coil 22 for wireless inductive charging of the energy storage device 14. A planar first shielding member 24 has an outer main surface 24a on which the receiving coil 22 is mounted. The first shielding member 24 may be larger than the receiving coil 22 such that the receiving coil 22 is sufficiently covered by the first shielding member 24. Preferably, the first shielding member 24 is larger than the receiving coil 22 such that the receiving coil 22 is completely covered by the first shielding member 24 as shown.

[0063] The wireless charging assembly 20 is arranged substantially perpendicular to the printed circuit board 18. This is most clearly shown in Figure 5, which is a view along a longitudinal axis of the aerosol generating device 2 that is substantially perpendicular to both the normal of the main surface 18a of the printed circuit board 18 and the normal of the outer main surface 24a of the first shielding member 24 (i.e., where the longitudinal axis and the normals define a mutually orthogonal coordinate system for the aerosol generating device 2).

[0064] The first shielding member 24 has a planar construction and is formed as a ferrite sheet or a sheet of ferrite-containing material. The first shielding member 24 is designed to shield components of the aerosol generating device 2 from the electromagnetic field that is generated by an inductive transmitting coil of an external wireless charger, for example, during wireless charging. The receiving coil 22 must be exposed to the electromagnetic field and the magnetic flux must extend into the receiving coil 22 so that the electromagnetic field generates an electric current in the receiving coil 22 and it is therefore mounted on the outer main surface 24a of the first shielding member 24 - i.e., between the first shielding member 24 and the outer housing 6 of the aerosol generating device 2. The receiving coil 22 is preferably positioned very close to, or in contact with, the facing part of the housing 6 for good wireless charging efficiency. In general, an efficiency of wireless charging depends on the distance between the transmitting coil and the receiving coil 22. The heater assembly 12, energy storage device 14 etc. may be positioned on the other side of the first shielding member 24. Such an arrangement may also contribute to shortening the distance between the transmitting coil and the receiving coil 22.

[0065] The receiving coil 22 includes a plurality of turns arranged substantially in a common plane. The receiving coil 22 therefore also has a planar construction so that the wireless charging assembly 20 as a whole is substantially planar.

[0066] The receiving coil 22 may be adhered to the outer main surface 24a of the first shielding member 24 using a thermal adhesive or tape, for example.

[0067] Arranging the wireless charging assembly 20, and in particular, the receiving coil 22, to be substantially perpendicular to the printed circuit board 18 means that any electronic components such as the MCU 19 that are mounted on the main surface of the printed circuit board 18 are better protected from any negative effects that may be caused by exposure to the generated electromagnetic field during wireless charging. In particular, such an arrangement may make it more difficult for magnetic flux to penetrate the electronic components as compared to an arrangement where the printed circuit board 18 is arranged substantially parallel to the wireless charging assembly 20, for example. In terms of protecting the printed circuit board 18, it may be possible to increase the size of the first shielding member 24 so that it also covers at least part of the printed circuit board 18, and perhaps even covers it completely. However, because the material used to form the first shielding member 24 is typically heavy (e.g., a ferrite or ferrite-containing material), increasing its size may make the aerosol generating device 2 too heavy for the user to hold comfortably, particularly for long periods, or for the user to carry on their person. An arrangement that reduces the exposure of the printed circuit board 18 to the generated magnetic field simply based on its physical orientation relative to the receiving coil 22 may therefore be beneficial.

[0068] The printed circuit board 18 is spaced apart from the wireless charging assembly 20 in a direction that is parallel to the normal of the main surface 18a of the printed circuit board 18. As shown in Figure 5, the printed circuit board 18 is spaced apart from the wireless charging assembly 20 by a distance DI along a transverse axis that is parallel with the normal of the main surface 18a of the printed circuit board 18. The printed circuit board 18 is also spaced apart from the wireless charging assembly 20 by a distance D2 along a lateral axis that is parallel with the normal of the outer main surface 24a of the first shielding member 24. The printed circuit board 18 partially overlaps with the wireless charging assembly 20 along the longitudinal axis - see Figures 3, 4 and 6-8. Such an arrangement better protects the electronic components mounted on the printed circuit board 18 from any negative effects that may be caused by exposure to the generated electromagnetic field during wireless charging because in general the negative effects of the electromagnetic field are reduced as you move away from the region of the transmitting coil and receiving coil 22.

[0069] A second shielding member 26 is positioned along the edge of the printed circuit board 18 that is closest to the wireless charging assembly 20. In particular, the second shielding member 26 extends generally into the gap or space 28 between the edge of the printed circuit board 18 and a facing edge of the wireless charging assembly 20, e.g., the facing edge of the first shielding member 24, as shown in Figure 5. The second shielding member 26 is a ferrite sheet or a sheet of ferrite-containing material, for example, and has an angled profile. The second shielding member 26 is significantly smaller than the first shielding member 24 and will therefore not significantly increase the weight of the aerosol generating device 2. The second shielding member 26 provides yet further protection for the electronic components mounted on the printed circuit board 18 that are known to be particularly sensitive to the negative effects of the electromagnetic field. Using a small number of additional shielding members for only the sensitive components will be beneficial in terms of keeping the weight of the aerosol generating device 2 as low as possible, while still providing sufficient protection.

[0070] The housing 6 forms at least part of the exterior of the aerosol generating device 2. The housing 6 has a substantially elliptical cross section - see Figure 9. But it may have a substantially rectangular cross section, for example. As also shown in Figure 9, the wireless charging assembly 20 is connected to a main surface 6a of the housing 6. The aerosol generating device 2 also includes a cover 30. The cover 30 is removably connected to the housing 6. The cover 30 covers part of the housing 6 and forms at least part of the exterior of the aerosol generating device 2. Such an arrangement of the housing 6 and the removable cover 30 may give the aerosol generating device 2 a different visual appearance - e.g., depending on the cover 30 that is being used, the visual appearance of the aerosol generating device 2 may be easily changed by the user. Figure 1 shows the cover 30 in position, but in Figures 2 and 9 the cover has been omitted. Figure 9 in particular shows how the cover 30 covers a curved end part 6b of the housing 6. Figure 9 also shows how the cover 30 - when present - extends around the printed circuit board 18 and how the second shielding member 26 has and angled profile so that it may be accommodated within the curved end part 6b of the housing 6. Depending on the material from which the cover 30 is formed, it may also protect the electronic components mounted on the printed circuit board 18 from any negative effects that may be caused by exposure to the generated electromagnetic field during wireless charging. In Figure 9 any other internal components of the aerosol generating device 2 such as the inner frame 54 that is shown in Figure 12 and described in more detail below have been omitted for clarity.

[0071] The PCBA 16 includes a connector 32 that is mounted to the printed circuit board 18. A pair of wires 34 is electrically connected between the receiving coil 22 and the connector 32 - e.g., for electrically connecting the receiving coil 22 to the printed circuit board 18. The unattached end of the pair of wires 34 includes a connector 36 that is compatible with the connector 32 mounted to the printed circuit board 18. For example, as shown in Figure 10, the connector 36 is a male-type connector and the mounted connector 32 is a female-type connector that includes a recess for receiving part of the male-type connector (i.e., the connectors are “plug-in” connectors). Alternatively, the connector 32 may be the male-type connector and the connector 36 may be the female-type connector. In another arrangement, the connectors 32, 36 may be of any other suitable type. The compatible connectors 32, 36 provide an easy way of electrically connecting the pair of wires 34 to the printed circuit board 18 during the assembly process and also allow for easy disconnection if required. The connectors 32, 36 may include cooperating locking features that temporarily lock the engaged connectors together, but which allow the engaged connectors to be released if necessary, e.g., if the receiving coil 22 needs to be disconnected from the printed circuit board 18. The connector 36 may include a gripping member (e.g., one or more ridges) that allows it to be gripped more easily. The housing 6 includes an opening 38 (see Figure 11) that corresponds to the position of the mounted connector 32. In other words, the opening 38 of the housing 6 is aligned with the mounted connector 32 so that it provides access to the mounted connector 32 from the exterior of the housing 6. This may help with assembling and / or disassembling the aerosol generating device 2. The opening 38 is in the curved end part 6b of the housing 6 that is covered by the cover 30. This means that the opening 38 is normally covered by the cover 30 to prevent ingress of dust or water into the interior of the housing 6 through the opening 38.

[0072] As shown in Figures 3, 6 and 8, the pair of wires 34 pass through a cut-out part 40 that is formed in an edge of the second shielding member 26.

[0073] The housing 6 includes an air inlet 42 and an air outlet 44. The air inlet 42 is covered or sealed by an air-permeable cover, e.g., by a hydrophobic membrane or similar. The air outlet 44 is covered or sealed by an air-permeable cover, e.g., a hydrophobic membrane or similar. The air-permeable covers will allow air to flow through the air inlet 42 and air outlet 44 but will prevent the ingress of water, dust etc. into the interior of the housing 6. The wireless charging assembly 20 includes an air flow path 46 fluidly connected between the air inlet 42 and the air outlet 44. Heated air may flow out of the housing 6 through the air outlet 44 and may be replaced by cooler air (e.g., at ambient temperature) flowing in to the housing 6 through the air inlet 42, for example. Cooling air may therefore flow through the air flow path 46 in one direction from the air inlet 42 to the downstream air outlet 44. The wireless charging assembly 20, and in particular, the first shielding member 24, therefore also functions as a heat exchanger so that heat that is generated during wireless charging is transferred to the cooling air and discharged outside the aerosol generating device 2 rather than being dissipated to the housing 6, for example. The air flow path 46 is arranged in a longitudinal direction - i.e., it extends substantially along the direction that is parallel to the longitudinal axis of the aerosol generating device 2. Having the air flow path extend along the longitudinal direction may be preferred because it allows the air inlet 42 and air outlet 44 to be positioned at upper and lower parts of the housing 6 - as shown in Figures 1 and 2 - where they are less likely to be covered by the hand of the user grasping the housing 6 or body of the aerosol generating device 2 during use.

[0074] The air flow path 46 is defined by the first shielding member 24. In particular, the air flow path 46 is formed by a central channel 48 in an inner main surface 24b of the first shielding member 24 - i.e., in the main surface that is opposite the outer main surface 24a on which the receiving coil 22 is mounted. The first shielding member 24 therefore provides shielding and functions as a heat exchanger. The cooling of the aerosol generating device 2 may therefore be improved without the need for an additional heat exchanger and without increasing the size and weight of the aerosol generating device 2. The channel 48 that defines the air flow path 46 extends between upper and lower edges of the first shielding member 24 as shown in Figures 4, 7 and 9, for example. Alternatively or additionally, a dedicated component may be used to form the air flow path 46 - e.g., a pipe or conduit that is fluidly connected between the air inlet 42 and the air outlet 44. This component may be used to transfer heat from the wireless charging assembly 20 to cooling air flowing through the component. In other words, the component may function has a heat exchanger. The wireless charging assembly 20 also includes a plurality of heat exchange paths 50 fluidly connected to the air flow path 46. The cooling may be further improved by transferring heat from the wireless charging assembly 20 to the cooling air through the one or more heat exchange paths 50. A width of each heat exchange path 50 may be less than a width of the air flow path 46. Heat exchange may therefore be improved by increasing the flow resistance of the cooling air in the one or more heat exchange paths 50. As shown in Figures 4, 7 and 9, the heat exchange paths 50 are fluidly connected to the air flow path 46 at an acute angle relative to the direction of air flow along the air flow path, i.e., where the cooling air is flowing from the air inlet 42 to the air outlet 44. This may improve the transfer of heated air from each heat exchange path 50 to the air flow path 46. Each heat exchange path 50 is defined by the first shielding member 24. In particular, each heat exchange path 50 is formed by a channel 52 in the inner main surface 24b of the first shielding member 24. The cooling of the aerosol generating device 2 may therefore be improved without the need for an additional heat exchanger and without increasing the size and weight of the aerosol generating device 2. The heat exchange paths 50 are formed symmetrically in a V-shaped pattern with the air flow path 46 extending substantially along the centre of the inner main surface 24b. The apex of each V-shaped pattern points towards the air outlet 44 or the downstream direction of the air flow path 46. Each heat exchange path 50 extends from the air flow path 46 to a side edge of the first shielding member 24.

[0075] The first shielding member 24 may be moulded (i.e., formed using moulding process) to include the integral channels 48, 52 in the inner main surface 24b that define the air flow path 46 and the V-shaped heat exchange paths 50, respectively. In the moulding process, a mould (not shown) can be provided where the channels 48, 52 are defined by raised areas, e.g., in a base surface of the mould. A compound material may be poured into the mould and may be compressed, e.g., by a piston. Any suitable compound material may be used. For example, the compound material may comprise a mixture of iron, nickel, and zinc oxides. The compressed compound material may be cured or sintered to form a planar sheet with an outer main surface 24a adapted to mount the receiving coil 22 and an inner main surface 24b with integral channels 48, 52 that define the air flow path 46 and the V-shaped heat exchange paths 50, respectively.

[0076] Referring to Figure 12, the aerosol generating device 2 includes an inner frame 54 that supports the heater assembly 8, the energy storage device 14 and the printed circuit board 18. The inner frame 54 is positioned inside the housing 6. (In Figure 12 the edge of the printed circuit board 18 is shown and the second shielding member 26 has been omitted for clarity.) The wireless charging assembly 20 is connected to the inner frame 54. In particular, the wireless charging assembly is connected using a plurality of click-fit connectors 56 that engage with the edges of the first shielding member 24. The click-fit connectors 56 are arranged so that they do not interfere with the air flow path that extended between the inner main surface 24a of the first shielding member 24 and the facing surface of the inner frame 54. This arrangement may be beneficial when assembling and / or disassembling the aerosol generating device 2 because no electrical connection is required to the housing 6.

[0077] The aerosol generating device 2 includes a second PCBA 58 - see Figure 12. A connecting member 60 such as at least one wire, for example, may be used to electrically connect the second PCBA 58 with the PCBA 16 on which the MCU 19 is mounted. The connecting member 60 may extend inside or through the inner frame 54. This may make it easier to assemble and / or disassemble the aerosol generating device 2, because such an extended connecting member will not cause an interference during the assembly or disassembly process. The second PCBA 58 may be useful for mounting one or more electrical components at an appropriate position within the aerosol generating device 2. For example, the second PCBA 58 may be used to mount a plug socket such as a universal serial bus (USB) socket (receptacle) for receiving a USB charging cable (plug) for wired charging of the aerosol generating device 2. The plug socket may be exposed to the exterior of the aerosol generating device 2, and may be located at a lower part of the housing 6.

[0078] Although exemplary embodiments have been described in the preceding paragraphs, it should be understood that various modifications may be made to those embodiments without departing from the scope of the appended claims. Thus, the breadth and scope of the claims should not be limited to the above-described exemplary embodiments. Any combination of the above-described features in all possible variations thereof is encompassed by the present disclosure unless otherwise indicated herein or otherwise clearly contradicted by context.

[0079] Unless the context clearly requires otherwise, throughout the description and the claims, the words “comprise”, “comprising”, and the like, are to be construed in an inclusive as opposed to an exclusive or exhaustive sense; that is to say, in the sense of “including, but not limited to”.

Claims

Claims1. An aerosol generating device (2) comprising: a heater assembly (8) comprising: a heating chamber (10) adapted to receive an aerosol generating article (4); and a heater (12) adapted to heat the aerosol generating article (4) when received in the heating chamber (10); a power source (14) adapted to supply power to the heater (12); a printed circuit board assembly (16) comprising: a controller adapted to control operation of the aerosol generating device (2); and a printed circuit board (18) having a main surface on which the controller is mounted; and a wireless charging assembly (20) comprising: an electrically conductive receiving coil (22) for wireless inductive charging; and a planar first shielding member (24) having a main surface (24a) on which the receiving coil (22) is mounted such that the receiving coil (22) is at least partially covered by the first shielding member (24); wherein the wireless charging assembly (20) is arranged substantially perpendicular to the printed circuit board (18).

2. An aerosol generating device (2) according to claim 1, further comprising a housing (6) that forms at least part of the exterior of the aerosol generating device (2) and which has a substantially elliptical or rectangular cross section, wherein the wireless charging assembly (20) is positioned adjacent a main surface (6a) of the housing (6), and is optionally connected to the main surface (6a) of the housing (6), and wherein the printed circuit board (18) is spaced apart from the wireless charging assembly (20) in a direction that is parallel to the normal of a main surface (18a) of the printed circuit board (18).

3. An aerosol generating device (2) according to claim 1 or claim 2, further comprising a second shielding member (26) adjacent the printed circuit board (18).

4. An aerosol generating device (2) according to claim 2 or claim 3, further comprising a cover (30) that covers part of the housing (6) and forms at least part of the exterior of the aerosol generating device (2), wherein the cover (30) extends around the printed circuit board (18).

5. An aerosol generating device (2) according to claim 4, wherein the printed circuit board assembly (16) further comprises a connector (32) that is mounted to the printed circuit board (18), wherein the wireless charging assembly (20) further comprises at least one wire (34) electrically connected between the receiving coil (22) and the connector (32), and wherein the housing (6) further comprises an opening (38) that corresponds to the position of the connector (32).

6. An aerosol generating device (2) according to claim 5, wherein the opening (38) is in the part of the housing (6) that is covered by the cover (30).

7. An aerosol generating device (2) according to any of claims 2 to 6, wherein the housing (6) further comprises an air inlet (42) and an air outlet (44), and wherein the wireless charging assembly (20) further comprises an air flow path (46) fluidly connected between the air inlet (42) and the air outlet (44).

8. An aerosol generating device (2) according to claim 7, wherein the air flow path (46) is defined by the first shielding member (24).

9. An aerosol generating device (2) according to claim 7 or claim 8, wherein the wireless charging assembly (20) further comprises one or more heat exchange paths (50) fluidly connected to the air flow path (46).

10. An aerosol generating device (2) according to claim 9, wherein a width of at least one heat exchange path (50) is less than a width of the air flow path (46).

11. An aerosol generating device (2) according to claim 9 or claim 10, wherein each heat exchange path (50) is fluidly connected to the air flow path (46) at an acute angle relative to the direction of air flow along the air flow path (46).

12. An aerosol generating device (2) according to any of claims 9 to 11, wherein each heat exchange path (50) is defined by the first shielding member (24).

13. An aerosol generating device (2) according to any of claims 2 to 12, further comprising an inner frame (54) adapted to support at least one of the heater assembly (8), the power source (14), and the printed circuit board (18), wherein a magnetic permeability of the inner frame (54) is less than a magnetic permeability of the first shielding member (24).

14. An aerosol generating device (2) according to claim 13, wherein the wireless charging assembly (20) is connected to the inner frame (54).

15. An aerosol generating device (2) according to claim 13 or claim 14, further comprising: a second printed circuit board assembly (58); and a connecting member (60) to electrically connect the second printed circuit board assembly to the printed circuit board assembly (16), wherein the connecting member (60) extends inside or through the inner frame (54).

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