Apparatus for aerosol generating devices

Abstract

To provide a system where a constituent aerosolizable material of an aerosol provision system (or a component thereof) is combusted or not combusted, in order to facilitate delivery to a user.SOLUTION: An apparatus for a non-combustible aerosol generating device comprises: a resonant circuit 51 comprising one or more inductive elements for inductively heating a susceptor apparatus to heat an aerosol generating material to thereby generate aerosol, where the inductive elements are mounted on a first external surface 54 of a substrate 53; a switching unit 52 enabling an alternating current to be generated from a voltage supply apparatus and to flow through one or more of the inductive elements to cause inductive heating of the susceptor apparatus, where the switching unit comprises a plurality of transistors mounted on a second external surface 55 of the substrate; and a heat sink 61 to which the inductive elements of the resonant circuit and the transistors of the switching unit are thermally connected via connections units 62, 63.SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] The present specification relates to an apparatus for an aerosol generating device. [Background technology]

[0002] Smoking articles, such as cigarettes and cigars, burn tobacco to produce smoke during use. Attempts have been made to create alternatives to these articles that release compounds without combustion. For example, tobacco heating devices heat an aerosol-generating substrate, such as tobacco, to form an aerosol by heating the substrate without burning it. Summary of the Invention

[0003] In a first aspect, the present specification describes an apparatus for an aerosol generating device, the apparatus comprising: one or more inductor elements (e.g., one or more induction coils) for inductively heating a susceptor unit to heat an aerosol-generating material and thereby generate an aerosol; a resonant circuit (e.g., an LC resonant circuit) mounted on a first outer surface of a substrate; an alternating current (AC) can be generated from a voltage supply (e.g., a DC voltage supply) that can cause the AC current to flow through one or more of the inductor elements to cause inductive heating of the susceptor unit; a switching unit (e.g., a bridge circuit) including a plurality of transistors mounted on a second outer surface of the substrate; and a heat sink to which the inductor elements of the resonant circuit and the transistors of the switching unit are thermally connected.

[0004] The transistors of the switching section may be implemented using one or more flat no-lead packages (dual flat no-lead packages, quad flat no-lead packages or similar technologies).

[0005] The heat sink may be at least partially formed on a first outer surface of the substrate. Alternatively or additionally, the heat sink may be at least partially formed on a second outer surface of the substrate.

[0006] The heat sink may be a copper heat sink.

[0007] The heat sink may be a ground plane.

[0008] The substrate may be a printed circuit board, such as a multilayer printed circuit board. The heat sink may be formed, at least in part, on an inner layer of the multilayer printed circuit board, for example.

[0009] The first outer surface of the substrate may be a top surface of the multilayer printed circuit board, and the second outer surface of the substrate may be a bottom surface of the multilayer printed circuit board.

[0010] The resonant circuit may further include a capacitor.

[0011] The switching section may be configured to provide an impulse generating circuit for applying an impulse to the resonant circuit, the applied impulse inducing an impulse response.

[0012] In a second aspect, the present specification describes a non-combustion aerosol generation system comprising the apparatus described above with reference to the first aspect. The apparatus may comprise a tobacco heating system. The aerosol-generating device may be configured to house a removable article comprising an aerosol-generating material. The aerosol-generating material may comprise, for example, an aerosol-generating substrate and an aerosol-forming material. The removable article may comprise the susceptor device.

[0013] In a third aspect, the present specification describes a kit of parts including an article for use in a non-combustion based aerosol generating system including an apparatus including any of the structures of the first aspect above or an aerosol generating device including any of the structures of the second aspect above. The article may include, for example, a removable article including an aerosol-generating material.

[0014] Exemplary embodiments will now be described, by way of example only, with reference to the following schematic drawings: [Brief explanation of the drawings]

[0015] [Figure 1] FIG. 1 is a block diagram of a system according to an exemplary embodiment. [Figure 2] 1 illustrates a non-combustion based aerosol delivery device according to an exemplary embodiment. [Figure 3] 1 is a diagram of a non-combustion based aerosol delivery device according to an exemplary embodiment. [Figure 4] 1 is a diagram of an article for use with a non-combustion based aerosol delivery device, according to an exemplary embodiment. [Figure 5] FIG. 2 is a block diagram of a circuit according to an exemplary embodiment. [Figure 6] FIG. 1 is a block diagram of a system according to an exemplary embodiment. [Figure 7] FIG. 1 is a block diagram of a system according to an exemplary embodiment. [Figure 8] FIG. 1 is a block diagram of a system according to an exemplary embodiment. [Figure 9] FIG. 1 is a block diagram of a system according to an exemplary embodiment. [Figure 10] FIG. 1 is a block diagram of a system according to an exemplary embodiment. [Figure 11] FIG. 1 is a block diagram of a system according to an exemplary embodiment. [Figure 12] FIG. 1 is a block diagram of a system according to an exemplary embodiment. [Figure 13] FIG. 1 is a block diagram of a system according to an exemplary embodiment. [Figure 14] FIG. 1 is a block diagram of a system according to an exemplary embodiment. [Figure 15] FIG. 1 is a block diagram of a system according to an exemplary embodiment. [Figure 16] 1 is a flowchart illustrating an algorithm according to an exemplary embodiment. [Figure 17] 1 is a plot illustrating an exemplary use of an exemplary embodiment. [Figure 18] 1 is a plot illustrating an exemplary use of an exemplary embodiment. [Figure 19]1 is a flowchart illustrating an algorithm according to an exemplary embodiment. [Figure 20] FIG. 2 is a block diagram of a circuit switching unit according to an exemplary embodiment. [Figure 21] 1 is a block diagram of a circuit switching unit according to an exemplary embodiment; [Figure 22] 1 is a flowchart illustrating an algorithm according to an exemplary embodiment. [Figure 23] 1 is a flowchart illustrating an algorithm according to an exemplary embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0016] As used herein, the term "delivery system" is intended to encompass a system that delivers a substance to a user; Combustible aerosol delivery systems, such as cigarettes, cigarillos, cigars and pipes or tobacco for roll-your-own or homemade cigarettes (whether based on tobacco, tobacco derivatives, expanded tobacco, reconstituted tobacco, tobacco substitutes or other smoking materials); non-combustion aerosol delivery systems that release compounds from aerosolizable materials without burning the aerosolizable material, such as e-cigarettes, tobacco heating products, and hybrid systems that generate aerosols using a combination of aerosolizable materials; an article including an aerosolizable material and configured for use in one of these non-combustible aerosol delivery systems; and Includes aerosol-free delivery systems such as lozenges, gums, patches, articles containing inhalable powders, and smokeless tobacco products such as snus and snuff that deliver nicotine-containing or non-nicotine-containing materials to the user without forming an aerosol.

[0017] For purposes of this disclosure, a "combustible" aerosol delivery system is one that combusts the constituent aerosolizable materials of the aerosol delivery system (or its components) to facilitate delivery to a user.

[0018] For purposes of this disclosure, a "non-combustion based" aerosol delivery system is one that may or may not combust the constituent aerosolizable materials of the aerosol delivery system (or its components) to facilitate delivery to the user.

[0019] In the embodiments described herein, the delivery system is a non-combustion based aerosol delivery system, for example, an electrically powered non-combustion based aerosol delivery system.

[0020] In one embodiment, the non-combustion based aerosol delivery system is an electronic cigarette, also known as a vape device or electronic nicotine delivery system (END), although the presence of nicotine in the aerosolizable material is not a requirement.

[0021] In one embodiment, the non-combustion based aerosol delivery system is a tobacco heating system, also known as a heated tobacco system.

[0022] In one embodiment, the non-combustion aerosol delivery system is a hybrid system that generates an aerosol using a combination of aerosolizable materials, one or more of which can be heated. Each of the aerosolizable materials can be, for example, in solid, liquid, or gel form, and may or may not contain nicotine. In one embodiment, the hybrid system includes a liquid or gel aerosolizable material and a solid aerosolizable material. The solid aerosolizable material can include, for example, tobacco or a non-tobacco product.

[0023] Generally, a non-combustion aerosol delivery system may include a non-combustion aerosol delivery device and an article for use with a non-combustion aerosol delivery system, although an article that itself includes a means for powering an aerosol-generating component may itself form a non-combustion aerosol delivery system.

[0024] In one embodiment, the non-combustion aerosol delivery device may include a power source and a controller. The power source may be a power source or a heat generating power source. In one embodiment, the heat generating power source includes a carbon substrate that can be energized to deliver power in the form of heat to an aerosolizable material or a heat transfer material in proximity to the heat generating power source. In one embodiment, a power source, such as a heat generating power source, is provided in an article to form the non-combustion aerosol delivery.

[0025] In one embodiment, an article for use in a non-combustion based aerosol sharing device may include an aerosolizable material, an aerosol-generating member, an aerosol-generating region, and a mouthpiece and / or region for receiving the aerosolizable material.

[0026] In one embodiment, the aerosol-generating element is a heater that can interact with the aerosolizable material to release one or more volatile substances from the aerosolizable material to form an aerosol. In one embodiment, the aerosol can be generated without heating the aerosolizable material. For example, the aerosol-generating element can generate the aerosol from the aerosolizable material without applying heat thereto, for example, by vibrational, mechanical, pressurized, or electrostatic means.

[0027] In one embodiment, the aerosolizable material may include an active material, an aerosol-forming material, and optionally one or more functional materials. The active material may include nicotine (optionally contained in tobacco or a tobacco derivative) and one or more other odorless physiologically active materials. An odorless physiologically active material is a material included in the aerosolizable material to achieve a physiological response other than olfaction.

[0028] The aerosol forming material may include one or more of glycerin, glycerol, propylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, 1,3-butylene glycol, erythritol, meso-erythritol, ethyl vanillate, ethyl laurate, diethyl base, triethyl citrate, triacetin, diacetin mixtures, benzyl benzoate, benzyl phenylacetate, tributyrin, lauryl acetate, lauric acid, myristic acid, and propylene carbonate.

[0029] The one or more functional ingredients may include one or more of a flavorant, a carrier, a pH regulator, a stabilizer, and / or an antioxidant.

[0030] In one embodiment, an article for use with a non-combustion aerosol delivery device may include an aerosolizable material or an area for containing an aerosolizable material. In one embodiment, an article for use with a non-combustion aerosol delivery device may include a mouthpiece. The area for containing an aerosolizable material may be a storage area for storing the aerosolizable material. In one embodiment, the area for containing the aerosolizable material may be separate from or combined with the aerosol-generation area.

[0031] An aerosolizable material, also referred to herein as an aerosol-generating material, is a material that can generate an aerosol when activated, for example, by heating, irradiation, or in some other manner. The aerosolizable material may be in the form of a solid, liquid, or gel, with or without, for example, nicotine and / or flavorings. In some embodiments, the aerosolizable material may comprise an "amorphous solid," which is alternatively referred to as a "monolithic solid" (i.e., non-fibrous). In some embodiments, the amorphous solid may be a dry gel. An amorphous solid is a solid material that holds a fluid, such as a liquid, within it.

[0032] The aerosolizable material may be present on a substrate, which may be or include, for example, paper, cardboard, paperboard, recycled aerosolizable material, plastic material, ceramic material, composite material, glass, metal, or metal alloy.

[0033] 1 is a block diagram of a system, generally designated by the reference numeral 10, according to an exemplary embodiment. System 10 includes a power supply in the form of a direct current (DC) voltage supply 11, a switching unit 13, a resonant circuit 14, a susceptor device 16, and a control circuit 18. Switching unit 13 and resonant circuit 14 may be coupled within an induction heating device 12.

[0034] The resonant circuit 14 may include a capacitor and one or more inductor elements that inductively heat the susceptor device 16, thereby heating the aerosol-generating material. Heating the aerosol-generating material thereby generates an aerosol.

[0035] The switching unit 13 can generate an AC current from the DC voltage supply 11. The AC current flows through one or more inductor elements, causing heating of the susceptor device 16. The switching unit may include multiple transistors. The DC-AC converter may include, for example, an H-bridge or an inverter circuit. Examples of these will be described later. It should be noted that the provision of a DC voltage supply 11 from which a pseudo-AC signal is generated is not an essential feature. For example, a controllable AC power supply or an AC-AC converter may be provided. Thus, an AC input (e.g., from a mains power supply or an inverter) can be provided.

[0036] Configuration examples of the switching unit 13 and the resonant circuit 14 will be explained in more detail below with reference to FIGS.

[0037] 2 and 3 illustrate a non-combustion-based aerosol generation apparatus, generally designated by the reference numeral 20, according to an exemplary embodiment. FIG. 3 is a perspective view of aerosol delivery device 20A with an outer cover. Aerosol delivery device 20A includes replaceable item 21, which is contained within (or provided elsewhere in) item 21 and may be inserted into aerosol delivery device 20A to enable heating of the susceptor. Aerosol delivery device 20A may further include an activation switch 22 used to turn aerosol delivery device 20A on and off. Additional components of aerosol delivery device 20 are shown in FIG. 3.

[0038] 3 shows aerosol delivery device 20B with the outer cover removed. Aerosol delivery device 20B includes item 21, activation switch 22, multiple inductor elements 23a, 23b, and 23c, and one or more air tube extensions 24 and 25. One or more air tube extensions 24 and 25 are not required.

[0039] Each of the multiple inductor elements 23a, 23b, and 23c may form part of a resonant circuit, such as the resonant circuit 14. The inductor element 23a may include a spiral inductor coil. In one example, the spiral inductor coil is made of Litz wire / cable wound in a spiral shape to provide the spiral inductor coil. Many alternative inductor configurations are possible, such as an inductor formed within a printed circuit board. The inductor elements 23b and 23c may be similar to the inductor element 23a. The use of three inductor elements 23a, 23b, and 23c is not required for all exemplary embodiments. Thus, the aerosol generating device 20 may include one or more inductor elements.

[0040] A susceptor may be provided as part of the item 21. In an exemplary embodiment, the aerosol generating device 20 may be activated by inserting the item 21 into the aerosol generating device. This may be done by detecting the presence of the item 21 in the aerosol generating device using a suitable sensor (e.g., an optical sensor) or, if the susceptor forms part of the item 21, by detecting the presence of the susceptor using, for example, the resonant circuit 14. Upon activation of the aerosol generating device 20, the inductor element 23 may cause the susceptor to inductively heat the item 21. In another embodiment, the susceptor may be provided as part of the aerosol generating device 20 (e.g., as part of a holder for receiving the item 21).

[0041] 4 is a diagram of an article, generally designated by the reference numeral 30, for use with a non-combustion-based aerosol delivery device, according to an exemplary embodiment. Item 30 is an example of replaceable item 21 described above with reference to FIGS. 2 and 3.

[0042] Article 30 includes a mouthpiece 31 and an aerosol-generating material 33, in this case a cylindrical rod of tobacco material, connected to mouthpiece 31. The aerosol-generating material 33 generates an aerosol when heated, for example, in a non-combustion aerosol-generating device, such as aerosol-generating device 20, as described herein. The aerosol-generating material 33 is enclosed in a wrapper 32. The wrapper 32 may be, for example, a paper or paper-lined metal foil wrapper. The wrapper 32 is substantially impermeable to air.

[0043] In one embodiment, the wrapper 32 comprises aluminum foil. Aluminum foil has been found to be particularly effective in promoting the formation of an aerosol within the aerosol-generating material 33. In this example, the aluminum foil has a metal layer having a thickness of approximately 6 μm. The aluminum foil may have a paper backing. However, in other arrangements, the aluminum foil may have other thicknesses, for example, between 4 μm and 16 μm. The aluminum foil also does not necessarily have a paper backing, but may or may not be backed with other materials, for example, to provide the foil with adequate tensile strength. Metal layers or foils other than aluminum may also be used. Furthermore, it is not necessary for such metal layers to be provided as part of the article 30. For example, such metal layers may be provided as part of the device 20.

[0044] The aerosol-generating material 33, also referred to herein as the aerosol-generating substrate 33, comprises at least one aerosol-forming material. In this example, the aerosol-forming material is glycerin. In another example, the aerosol-forming material may be another material or combination thereof, as described herein. The aerosol-forming material has been found to improve the sensory performance of the article by aiding in the transfer of compounds, such as flavor compounds, from the aerosol-generating material to the consumer.

[0045] 4, the mouthpiece 31 of the article 30 includes an upstream end 31a adjacent the aerosol-generating substrate 33 and a downstream end 31b distal from the aerosol-generating substrate 33. The aerosol-generating substrate includes tobacco, although substitutions are possible.

[0046] Mouthpiece 31 includes a body of material 36 upstream of, and in this example adjacent and abutting relationship to, hollow tubular member 34. Body of material 36 and hollow tubular member 34 each define a substantially cylindrical overall outer shape and share a common longitudinal axis. Body of material 36 is wrapped in a first plug wrapper 37. First plug wrapper 37 may have a basis weight of less than 50 gsm, such as between about 20 gsm and 40 gsm.

[0047] In this example, the hollow tubular member 34 is a first hollow tubular member 34, and the mouthpiece includes a second hollow tubular member 38, also referred to as a cooling member, upstream of the first hollow tubular member 34. In this example, the second hollow tubular member 38 abuts the upstream body of material 36. The body of material 36 and the second hollow tubular member 38 each define a substantially cylindrical overall outer shape and share a common longitudinal axis. The second hollow tubular member 38 is formed from multiple parallel-wound paper layers, butted together at seams to form the tubular member 38. In this example, the first and second paper layers are provided in a two-ply tube; however, in other examples, three, four, or more paper layers can be used to form a three-ply, four-ply, or more ply tube. Other constructions can be used, such as spirally wound layers of paper, cardboard tubes, tubes formed using a paper mache tube process, and molded or extruded plastic tubes. The second hollow tubular member 38 can also be formed using a stiff plug wrapper and / or tipping paper as the second plug wrapper 39 and / or tipping paper 35 described herein, meaning that a separate tubular member is not required.

[0048] The second hollow tubular member 38 is disposed around the mouthpiece 31, functioning as a cooling section, and defines a void within the mouthpiece 31. The void provides a chamber through which heated volatile components generated by the aerosol-generating material 33 can flow. The second hollow tubular member 38 is hollow to provide an aerosol accumulation chamber, yet is sufficiently rigid to withstand axial compressive forces and bending moments that may occur during manufacturing and use of the article 21. The second hollow tubular member 38 provides a physical displacement between the aerosol-generating material 33 and the body of material 36. The physical displacement provided by the second hollow tubular member 38 provides a temperature gradient across the length of the second hollow tubular member 38.

[0049] Of course, item 30 is provided by way of example only, and those skilled in the art will be aware of many alternative arrangements of such items that may be used in the systems described herein.

[0050] 5 is a block diagram of a circuit, generally designated by the reference numeral 40, according to an exemplary embodiment. Circuit 40 includes a positive terminal 47 and a negative (ground) terminal 48 (which are an example implementation of DC voltage supply 11 of system 10 described above). Circuit 40 includes a switching unit 44 (implementing switching unit 13 described above), where switching unit 44 includes a bridge circuit (e.g., an H-bridge circuit, such as a FET H-bridge circuit). Switching unit 44 includes a first circuit branch 44a and a second circuit branch 44b, which are coupled by a resonant circuit 49 (implementing resonant circuit 14 described above). First circuit branch 44a includes switches 45a and 45b, and second circuit branch 44b includes switches 45c and 45d. Switches 45a, 45b, 45c, and 45d are transistors, such as field-effect transistors (FETs), and can receive input from a control device, such as control circuit 18 of system 10. Resonant circuit 49 includes capacitor 46 and inductor element 43, such that resonant circuit 49 is an LC resonant circuit. Circuit 40 further illustrates susceptor equivalent circuit 42 (thereby embodying susceptor device 16). Susceptor equivalent circuit 42 includes resistor and inductor elements that illustrate the electrical effects of the exemplary susceptor device 16. When a susceptor is present, susceptor device 42 and susceptor element 43 can function as transformer 41. Transformer 41 can generate a varying magnetic field such that the susceptor is heated when circuit 40 receives power. During a heating operation in which susceptor device 16 is heated by an induction device, switching unit 44 is driven (e.g., by control circuit 18) to alternately connect first and second branches to allow alternating current to flow through resonant circuit 14. The resonant circuit 14 has a resonant frequency based in part on the susceptor device 16, and the control circuit 18 is configured to control the switching element 44 to switch at or near the resonant frequency. Driving the switch circuit at or near resonance improves efficiency and reduces energy lost in the switching element (which would otherwise unnecessarily heat the switching element). In the example where an article 21 containing aluminum foil is heated, the switching element 44 is driven at a frequency of about 2.5 MHz. However, in other implementations, the frequency may be, for example, For example, it is somewhere between 500 kHz and 4 MHz.

[0051] A susceptor is a material that can be heated by penetration of a varying magnetic field, such as an alternating magnetic field. The heating material can be a conductive material, so that penetration by the varying magnetic field causes induction heating of the heating material. The heating material can be a magnetic material, so that penetration by the varying magnetic field causes magnetic hysteresis heating of the heating material. The heating material can be either conductive or magnetic, so that the heating material can be heated by both heating mechanisms.

[0052] Induction heating is the process of heating a conductive object by penetrating a changing magnetic field into the object. This process is explained by Faraday's law of electromagnetic induction and Ohm's law. An induction heater can include an electromagnet and a device for passing a changing current, such as an alternating current, through the electromagnet. When the object to be heated and the electromagnet are positioned relative to each other so that the changing magnetic field generated by the electromagnet penetrates the object, one or more eddy currents are generated within the object. The object has a resistance to the flow of current. Therefore, when such eddy currents are generated within the object, they flow against the object's electrical resistance, thereby heating the object. This process is called Joule heating, ohmic heating, or resistive heating. An object that can be inductively heated is known as a susceptor.

[0053] In one embodiment, the susceptor is in the form of a closed circuit. In some embodiments, it has been found that when the susceptor is in the form of a closed circuit, the magnetic coupling between the susceptor and the electromagnet during use is enhanced, resulting in greater or improved Joule heating.

[0054] Magnetic hysteresis heating is the process of heating an object made of a magnetic material due to the penetration of a changing magnetic field into the object. Magnetic materials can be thought of as containing many atomic-scale magnets, or magnetic dipoles. When a magnetic field penetrates such a material, the magnetic dipoles align along the field. Thus, when a changing magnetic field, such as that produced by an alternating magnetic field, penetrates a magnetic material, the orientation of the magnetic dipoles changes in response to the applied changing magnetic field. This reorientation of the magnetic dipoles generates heat within the magnetic material.

[0055] When an object is both conductive and magnetic, the penetration of a changing magnetic field into the object can cause both Joule heating and magnetic hysteresis heating in the object. Furthermore, the use of magnetic materials can enhance the changing magnetic field, thereby enhancing Joule heating.

[0056] In each of the above processes, heat is generated within the object itself, rather than by conduction from an external heat source, which allows for rapid temperature rise and more uniform heat distribution within the object. This can be achieved, among other things, by choosing the object's material and geometry and the magnitude and orientation of the varying magnetic field relative to the object. Furthermore, induction heating and magnetic hysteresis heating do not require a physical connection between the source of the varying magnetic field and the object, thereby increasing design freedom and control of the heating profile and reducing costs.

[0057] FIG. 6 is a block diagram of a system, generally designated by the reference numeral 50, according to an exemplary embodiment. System 50 includes a resonant circuit 51 (similar to resonant circuit 14), a switching unit 52 (similar to switching unit 13), and a substrate 53. As discussed above with respect to FIG. 5, resonant circuit 51 includes one or more inductor elements, and switching unit 52 includes a plurality of transistors. The one or more inductor elements may be mounted on a first outer surface 54 of substrate 53. The plurality of transistors may be mounted on a second outer surface 55 of substrate 53. Substrate 53 may be a printed circuit board (PCB). Resonant circuit 51 may include a capacitor, although the capacitor may be located elsewhere in system 50, as described below.

[0058] The resonant circuit 51 and the switching unit 52 generate heat that increases the overall temperature of the system 50. It is beneficial to mount the resonant circuit 51 (or at least one or more inductor elements thereof) on a first surface 54 and the switching unit 52 on a second surface 55 such that the resonant circuit 51 and the switching unit 52 are at least partially thermally insulated from each other by the substrate 53.

[0059] 7 is a block diagram of a system generally designated by the reference numeral 60A, according to an exemplary embodiment. System 60A (shown in cross section) includes a substrate 53, one or more inductor elements of a resonant circuit 51 mounted on a first outer surface 54 of substrate 53, a plurality of transistors of a switching unit 52 mounted on a second outer surface 55 of substrate 53, and a heat sink 61. The one or more inductor elements of resonant circuit 51 are thermally coupled to heat sink 61 via connections 62, and the plurality of transistors of switching unit 52 are thermally coupled to heat sink 61 via connections 63.

[0060] In an exemplary embodiment, switching unit 52 may be implemented using one or more integrated circuits. The integrated circuits may be provided within a protective material (such as plastic) that provides some protection against damage from handling or other causes to the integrated circuit. Such a configuration is typically known as a package (or sometimes an electrical package). Because the package provides protection for the integrated circuits embedded (or encased) within the protective material, heat dissipation may be adversely affected. The multiple transistors of switching unit 52 may be implemented using one or more flat no-lead packages. The flat no-lead package may be a dual flat no-lead (DFN), quad flat no-lead (QFN) package, or similar package.

[0061] The use of a DFN or QFN package can improve heat dissipation from switching portion 52 to substrate 53 on which the DFN / QFN package is mounted. DFN and QFN packages typically include an exposed thermal pad (i.e., a metal or other member having at least one exposed surface that is not covered by a protective material) that can improve heat dissipation. The improved heat dissipation allows switching portion 52 to operate with loads that generate more heat than would be achievable using other integrated circuit geometries that do not use a DFN or QFN package.

[0062] Heat sink 61 increases heat dissipation, thereby maintaining the temperature of the printed circuit board below a threshold temperature. Heat sink 61 may be formed on first exterior surface 54 of substrate 53. Heat sink 61 (and other heat sinks described herein) may absorb, dissipate, and distribute heat in the form of, for example, a mass of copper (e.g., a copper plane). Those skilled in the art will recognize alternative configurations.

[0063] The heat sink 61 may be configured such that the resonant circuit 51 is only thermally connected to the heat sink 61 via the connection 62. The remaining surface of the heat sink 61 may then be separated from the surface of the resonant circuit 51 by a fluid such as air or any other cooling medium.

[0064] In implementations in which switching portion 52 is implemented using one or more flat no-lead packages, connection portion 63 may extend from the thermal pad to heat sink 61. Connection portion 63 may pass through substrate 53, for example in the form of a via.

[0065] 8 is a top view of a system 60A, generally designated by the reference numeral 60B, according to an exemplary embodiment. As shown in top view 60B, heat sink 61 and resonant circuit 51 (or at least one or more inductor elements thereof) may be separated by a gap 64 or other electrical insulating material, for example, to prevent short circuits.

[0066] 9 is a block diagram of a system, generally designated by reference numeral 70, according to an exemplary embodiment. System 70 includes substrate 53, one or more inductor elements of resonant circuit 51 mounted on first outer surface 54 of substrate 53, a plurality of transistors of switching unit 52 mounted on second outer surface 55 of substrate 53, and a heat sink 71. The one or more inductor elements of resonant circuit 51 are thermally connected to heat sink 71 via connections 72, and the plurality of transistors of switching unit 52 are thermally connected to heat sink 71 via connections 73. Heat sink 71 may be formed on second outer surface 55 of substrate 53.

[0067] The heat sink 71 may be configured such that the switching portion 52 is only thermally connected to the heat sink 71 via the connection portion 73. The remaining surface of the heat sink 71 may therefore be separated from the surface of the resonant circuit 51 by a fluid such as air or any other cooling medium.

[0068] In implementations in which switching unit 52 is implemented using one or more flat no-lead packages, the thermal pad may be connected directly to heat sink 71. The thermal pad is electrically isolated from the integrated circuit.

[0069] 10 is a bottom view of system 70A, generally designated by reference numeral 70B, according to an exemplary embodiment. As shown in bottom view 70B, heat sink 71 and switching portion 52 may be separated by gap 74 or other electrical insulation to prevent, for example, short circuits.

[0070] In an exemplary embodiment, heat sink 61 and / or 72 may be a copper heat sink. Alternatively, heat sink 61 and / or 71 may be an aluminum heat sink. In an exemplary embodiment, heat sink 61 and / or 71 may be a ground plate.

[0071] Heat sinks, such as heat sinks 61 and 71, transfer thermal energy from a hot device to a cold fluid medium. The fluid medium is often air, but can also be water, coolant, or oil. When the fluid medium is water, the heat sink is sometimes referred to as a cold plate. A heat sink can also be a thermal sink that can absorb any amount of heat without significantly changing its temperature.

[0072] 11 is a block diagram of a system, generally designated by the reference numeral 80, according to an exemplary embodiment. System 80 includes resonant circuit 51, switching section 52, and substrate 81. Substrate 81 may be a printed circuit board. Printed circuit board 81 may be a multilayer printed circuit board including multiple layers 82.

[0073] 12 is a block diagram of a system, generally designated by the reference numeral 90, according to an exemplary embodiment. System 90 includes resonant circuit 51, switching unit 52, substrate 92, and heat sink 91. Substrate 92 may be a multilayer printed circuit board. Heat sink 91 may be at least partially formed on an inner layer of substrate 92, which is a multilayer printed circuit board. Resonant circuit 51 may be thermally connected to heat sink 91 via connection 93, and switching unit 52 may be thermally connected to heat sink 91 via connection 94.

[0074] 13 is a block diagram of a system, generally designated by reference numeral 100, according to an exemplary embodiment. System 100 includes resonant circuit 51, switching section 52, substrate 101, and multiple layers 102, 103, and 104. These layers include layer 103 formed on a first outer surface of substrate 101, layer 102 formed on an inner layer of substrate 101, and layer 104 formed on a second outer surface of substrate 101. One or more of layers 102-104 can be used as a heat sink. Additionally, one or more of layers can be used for some other purpose (e.g., routing electrical signals).

[0075] For example, the resonant circuit 51 is thermally and / or electrically connected to one or more of these layers 102-104 (e.g., via connections 109, 105, and 108, respectively). Similarly, the switching unit 52 is thermally and / or electrically connected to one or more of the layers 102-104 (e.g., via connections 110, 107, and 108, respectively).

[0076] In some of the exemplary configurations described above, the resonant circuit is located on a first outer surface of a substrate (e.g., a printed circuit board), the switching unit is located on a second outer surface of the substrate, and the resonant circuit includes one or more inductor elements and at least one capacitor. This is not required for all embodiments. For example, FIG. 14 is a block diagram of an exemplary embodiment of a system, generally designated by the reference numeral 110, including one or more inductor elements 111, a switching unit 112, and at least one capacitive element 113. The one or more inductor elements and the one or more capacitive elements form one or more resonant circuits. The one or more inductor elements are mounted on a first outer surface 115 of a substrate 114. The switching unit (e.g., the plurality of transistors described above) is mounted on a second outer surface 116 of the substrate 114. In this exemplary system 110, one or more capacitors are also mounted on the second outer surface 116 of the substrate.

[0077] 15 is a block diagram of a system, generally designated by the reference numeral 200, according to an exemplary embodiment. The system 200 includes the resonant circuit 14 and susceptor 16 of the system 10 described above. The system 200 further includes an impulse generating circuit 202 and an impulse response processor 204. The impulse generating circuit 202 and the impulse response processor 204 may be implemented as part of the control circuit 18 of the system 10.

[0078] The impulse generating circuit 202 switches between positive and negative voltage sources to generate impulses, and is therefore implemented using a first switching unit (such as an H-bridge circuit). For example, the switching unit 44 described above with reference to FIG. 5 may be used. As described further below, the impulse generating circuit 202 can generate impulses by changing the switching state of the FETs in the switching unit 44 from one state in which switches 45b and 45d are both on (so that the switching unit is grounded) and switches 45a and 45b are off, to the opposite state of one of the switches in the first and second circuit branches 44a and 44b. Alternatively, the impulse generating circuit 202 can be implemented using a pulse-width modulation (PWM) circuit. Other impulse generation arrangements are possible.

[0079] Based on the impulse response, the impulse response processor 204 can determine one or more performance metrics (or characteristics) of the resonant circuit 14 and the susceptor 16. Such performance metrics may include characteristics of the item (such as the removable item 21), the presence or absence of such item, the type of item, the operating temperature, etc.

[0080] 16 is a flow chart illustrating an algorithm, generally designated by the reference numeral 210, according to an exemplary embodiment. The algorithm 210 illustrates an example use of the system 200.

[0081] The algorithm 210 begins with operation 212 where an impulse (generated by the impulse generating circuit 202) is applied to the resonant circuit 14. Figure 17 is a plot generally designated by the reference numeral 220, illustrating an exemplary impulse applied in operation 212.

[0082] The impulse may be applied to the resonant circuit 14. Alternatively, in a system having multiple inductor elements (such as the non-combustion based aerosol device 20 described above with reference to FIGS. 2 and 3), the impulse generating circuit 202 may select one of multiple resonant circuits, each including an inductor element and a capacitor for inductively heating a susceptor, where the applied impulse induces an impulse response between the capacitor and the inductor element of the selected resonant circuit.

[0083] In operation 214, an output is generated (by the impulse response processor 204) based on the impulse response generated in response to the impulse applied in operation 212. FIG. 18, a plot generally designated 225, illustrates an exemplary impulse response received by the impulse response processor 204 in response to the impulse 220. As shown in FIG. 18, the impulse response may take the form of a ringing resonance. The impulse response is the result of charge bouncing between the inductor and capacitor of the resonant circuit 14. In one configuration, this results in no heating of the susceptor; that is, the temperature of the susceptor remains substantially constant (e.g., within ±1°C or ±0.1°C of the temperature before applying the impulse).

[0084] At least some of the characteristics of the impulse response (e.g., the frequency and decay rate of the impulse response) provide information about the system to which the impulse is applied. Thus, system 200 can be used to determine one or more characteristics of the system to which the impulse is applied. For example, one or more performance characteristics, such as a fault condition, a characteristic of the inserted item 21, the presence or absence of such an item, whether the item 21 is genuine, or an operating temperature, can be determined based on the output signal derived from the impulse response. System 200 can use the determined one or more characteristics of system 10 to perform a further action (or prevent a further action, if necessary) to, for example, heat the susceptor device 16. For example, based on the determined operating temperature, system 200 can select the power level to be supplied to the induction device to cause further heating of the susceptor device, or whether power should be supplied at all. Some performance characteristics, such as determining a fault condition or whether the item 21 is genuine, can involve comparing a measured characteristic of the system (measured using the impulse response) to an expected value or range of values for the characteristic, and the action taken by system 200 based on the comparison.

[0085] 19 is a flow chart illustrating an algorithm, generally designated by reference numeral 230, according to an exemplary embodiment. Operation 232 of algorithm 230 applies an impulse to resonant circuit 14 by impulse generating circuit 202. Operation 232 is therefore the same as operation 212 described above.

[0086] In operation 234 of the algorithm 230, the period of the impulse response induced in response to the applied impulse is determined by the impulse response processor 204. Finally, in operation 236, an output (based on the determined period of the impulse response) is generated.

[0087] 20 is a block diagram of a circuit switching section, generally designated by the reference numeral 380, according to an exemplary embodiment. Switching section 380 illustrates the switch positions of circuit 40 in a first state, generally designated by the reference numeral 382, and a second state, generally designated by the reference numeral 383.

[0088] In a first state 382, switches 45a and 45c of circuit 40 are off (i.e., open), and in a second state 383, switches 45b and 45d are on (i.e., closed). Thus, both sides of resonant circuit 49 are connected to ground in first state 382. In second state 383, a voltage pulse (i.e., impulse) is applied to the resonant circuit.

[0089] 21 is a block diagram of a circuit switching section, according to an exemplary embodiment, generally designated by the reference numeral 390. Switching section 390 illustrates the switch positions of circuit 40 in a first state, generally designated by the reference numeral 392, and a second state, generally designated by the reference numeral 393.

[0090] In a first state 392, switch 45b is connected (i.e., closed) and switches 45a, 45c, and 45d are disconnected (i.e., open), thus connecting one side of resonant circuit 49 to ground. In a second state 393, a voltage pulse (i.e., impulse) is applied to the resonant circuit.

[0091] In the second state 382 of the switching unit 380, the current flows through the first switch 45a, the resonant circuit 49 , and switch 45d. This current flow can cause heat generation and discharge of the power source (such as a battery). In the second state 393 of the switching unit 390, no current flows through switch 45d, reducing heat generation and power source discharge. Furthermore, noise generation can be reduced when each impulse is generated.

[0092] 22 is a flow chart illustrating an algorithm according to an exemplary embodiment, generally designated by the reference numeral 400. Algorithm 400 illustrates an example use of the system described herein.

[0093] The algorithm 400 begins with a measurement operation 401. The measurement operation 401 may include, for example, a temperature measurement. Next, in operation 402, a heating operation is performed. The performance of the heating operation 402 may depend on the output of the measurement operation 401. Once the heating operation 402 is complete, the algorithm 400 returns to operation 401, where the measurement operation is repeated.

[0094] Operation 401 is performed in system 200 where an impulse is applied by impulse generating circuit 202 and a measurement (e.g., a temperature measurement) is determined based on the output of impulse response processor 204. As described above, the temperature measurement may be based on, for example, a decay rate, an impulse response time, an impulse response period, etc.

[0095] Operation 402 may be performed by controlling induction heating device 12 to heat susceptor 16 of system 10. Induction heating device 12 may be driven at or near the resonant frequency of a resonant circuit to cause efficient heating. The resonant frequency may be determined based on the output of operation 401.

[0096] In one implementation of algorithm 400, a measurement operation is performed for a first time period, a heating operation 402 is performed for a second time period, and then the process is repeated. For example, the first time period is 10 milliseconds and the second time period is 250 milliseconds, although other time intervals are possible. In other words, a measurement operation is performed between successive heating operations. However, a heating operation 402 performed for a second time period does not necessarily mean that power is supplied to the induction coil for the entire second time period. For example, power may be supplied for only a portion of the second time period.

[0097] In an alternative embodiment, algorithm 400 is implemented with heating operations 402 whose duration depends on the level of heating required (if more heating is required, the heating duration increases; if less heating is required, the heating duration decreases). In such an algorithm, measurement operation 401 is simply performed when no heating is being performed, so that heating operation 402 does not need to be interrupted to perform measurement operation 401. This alternating heating section is sometimes referred to as a pulse width modulation approach to heating control. For example, a pulse width modulation scheme is provided at a frequency on the order of 100 Hz, with each period divided into a heating portion and a measurement portion (of variable length).

[0098] 23 is a flow chart illustrating an algorithm according to an exemplary embodiment, generally designated by the reference numeral 410. The algorithm 410 can be implemented using the system 200 described above.

[0099] Algorithm 410 begins at operation 411, where switch circuit 13 (e.g., circuit 40) applies an impulse to resonant circuit 14. At operation 413, the impulse response (e.g., as detected by impulse response processor 64) is used to determine whether an item (e.g., item 21) is present in the system being heated. As discussed above, the presence of item 21 affects the impulse response in a detectable manner.

[0100] If an item is detected at operation 413, the algorithm 410 moves to operation 415. Otherwise, the algorithm ends at operation 419.

[0101] A measuring and heating operation is performed in operation 415. For example, operation 415 can be performed using the above algorithm 400. Of course, alternative measuring and heating arrangements can be provided.

[0102] Once a number of heating measurements and heating cycles have been performed, the algorithm 400 moves to operation 417, where it is determined whether the heating should be stopped (e.g., if the heating period has expired or in response to user input). If so, the algorithm ends at operation 419; if not, the algorithm 400 returns to operation 411.

[0103] Of course, the above techniques for determining one or more characteristics of an inductive or susceptor portion can be applied to individual inductor elements. For systems including multiple inductor elements, such as system 20 including three inductor elements 23a, 23b, and 23c, the system can be configured to determine one or more parameters, such as temperature, for each of the inductor elements using the above techniques. In some implementations, it may be beneficial for the system to operate using individual measurements for each inductor element. In other implementations, it may be beneficial for the system to operate using only a single measurement of multiple inductors (e.g., to determine whether article 21 is present). In such situations, the system is configured to determine an average measurement corresponding to the measurements obtained from each inductor element. In other examples, one or more characteristics can be determined using only one of the multiple inductor elements.

[0104] The various embodiments described herein are provided merely to aid in understanding and teaching the claimed features. These embodiments are merely representative examples and are not intended to be comprehensive or exclusive. It should be understood that the advantages, embodiments, examples, functions, features, structures, and / or other aspects of the present disclosure should not be construed as limiting the disclosure to the exact scope of the claims or to the equivalents of the claims, and that other embodiments may be utilized or modified without departing from the scope and / or spirit of the present disclosure. Various embodiments may suitably comprise, consist of, or consist essentially of the disclosed elements, components, features, parts, steps, means, or other combinations. The present disclosure also encompasses other inventions not currently claimed but which may be claimed in the future.

Claims

1. the susceptor device includes one or more inductor elements for inductively heating the aerosol-generating material to thereby generate an aerosol, the inductor elements including a resonant circuit mounted on a first outer surface of the substrate; a switching section including a plurality of transistors mounted on the second outer surface of the substrate, the switching section being capable of generating an alternating current from a voltage supply and causing it to flow through one or more of the inductor elements to cause inductive heating of the susceptor device; An apparatus for an aerosol generating device comprising an inductor element of a resonant circuit and a heat sink to which transistors of a switching unit are thermally connected, the transistors of the switching unit being mounted using one or more flat no-lead packages having exposed thermal pads, and the transistors being thermally connected to the heat sink via connections extending from the exposed thermal pads of each of the no-lead packages to the heat sink.

2. 2. The device according to claim 1, wherein the flat no-lead package is a dual flat no-lead package or a quad flat no-lead package.

3. 3. The apparatus of claim 1, wherein the heat sink is formed at least in part on the first outer surface of the substrate.

4. 4. The apparatus of claim 1, wherein the heat sink is formed at least in part on the second outer surface of the substrate.

5. 5. The device according to claim 1, wherein the heat sink is a copper heat sink.

6. 6. The device according to claim 1, wherein the heat sink is a ground plate.

7. 7. Apparatus according to any one of claims 1 to 6, characterized in that the substrate is a printed circuit board.

8. 8. The apparatus of claim 7, wherein the printed circuit board is a multilayer printed circuit board.

9. 9. The apparatus of claim 8, wherein the heat sink is formed at least in part on an inner layer of a multilayer printed circuit board.

10. 10. The apparatus of claim 8 or 9, wherein the first outer surface of the substrate is a top surface of the multilayer printed circuit board and the second outer surface of the substrate is a bottom surface of the multilayer printed circuit board.

11. 11. The device according to claim 1, wherein the switching unit includes a bridge circuit.

12. 12. Apparatus according to any one of claims 1 to 11, characterized in that the inductor element is an induction coil.

13. 13. The device according to any one of claims 1 to 12, wherein the resonant circuit further comprises a capacitor.

14. 14. Apparatus according to any one of the preceding claims, characterized in that the switching unit is arranged to provide an impulse generating circuit for applying an impulse to the resonant circuit, the applied impulse inducing an impulse response.

15. 15. Apparatus according to any one of the preceding claims, characterized in that the voltage supply is a DC voltage supply.

16. A non-combustion aerosol generating device comprising the apparatus of any one of claims 1 to 15.

17. 17. The non-combustion aerosol generating device of claim 16, wherein the aerosol generating device is configured to house a removable article containing an aerosol-generating material.

18. 18. The non-combustion aerosol-generating device according to claim 17, wherein the aerosol-generating material includes an aerosol-generating base material and an aerosol-forming material.

19. 19. The non-combustion aerosol generating device according to claim 17 or 18, wherein the removable article includes the susceptor device.

20. 20. A non-combustion aerosol generating device according to any one of claims 16 to 19, wherein the device includes a tobacco heating system.

21. A kit of parts including articles for use in a non-combustion based aerosol generating system, the non-combustion based aerosol generating system including an apparatus as claimed in any one of claims 1 to 15 or an aerosol generating device as claimed in any one of claims 16 to 20.

22. 22. The kit of parts of claim 21, wherein the article is a removable article containing an aerosol-generating material.

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