Induction heating assembly for an aerosol generating device - Patent Application 20070123633

Abstract

An induction heating assembly (10) for an aerosol generating device (100). The induction heating assembly (10) comprises an induction coil (12), a heating section (14) configured to receive an aerosol-generating substrate, and a structure (16) disposed around the induction coil (12). The structure (16) includes a first electromagnetic shielding layer (18), a second electromagnetic shielding layer (20) disposed outside the first electromagnetic shielding layer (18), and a first insulating layer (22) disposed between the first electromagnetic shielding layer (18) and the second electromagnetic shielding layer (20). The first insulating layer (22) has an inner surface (26) in contact with an outer surface (28) of the first electromagnetic shielding layer (18) and an outer surface (30) in contact with an inner surface (32) of the second electromagnetic shielding layer (20).

Description

[Technical field]

[0001] The present disclosure relates generally to an inductive heating assembly for an aerosol generating device, and more particularly to an inductive heating assembly for an aerosol generating device for heating an aerosol-generating substrate to generate an aerosol for a user to inhale. Embodiments of the present disclosure also relate to an aerosol generating device. [Background technology]

[0002] In recent years, devices that generate aerosols for inhalation by heating, rather than burning, aerosol-generating substrates have become popular with consumers.

[0003] Such devices may use one of several different approaches to providing heat to the substrate, one such approach being to provide an aerosol generating device that employs an inductive heating system that includes an inductor.

[0004] When a user activates the device, electrical energy is supplied to the inductor, which generates an alternating electromagnetic field. The susceptor couples with the electromagnetic field to generate heat, which is transferred, for example by conduction, to the substrate, which heats up and generates an aerosol for inhalation by the user of the device. Summary of the Invention [Problem to be solved by the invention]

[0005] A drawback of using induction heating systems is that electromagnetic field leakage can occur. Additionally, the generated heat can cause the housing of the device to become hot. Therefore, these drawbacks need to be addressed. [Means for solving the problem]

[0006] According to a first aspect of the present disclosure, there is provided an inductive heating assembly for an aerosol generating device, the inductive heating assembly comprising: a tubular heating section configured to receive an aerosol-generating substrate; A helical induction coil surrounding the tubular heating section; a structure disposed around the helical induction coil; The structure comprises: a first electromagnetic shielding layer, a second electromagnetic shielding layer disposed outside the first electromagnetic shielding layer; a first thermal insulation layer disposed between the first electromagnetic shield layer and the second electromagnetic shield layer; Including, An induction heating assembly is provided in which a first thermal insulation layer has an inner surface in contact with the outer surface of the first electromagnetic shield layer and an outer surface in contact with the inner surface of the second electromagnetic shield layer.

[0007] The structure reduces leakage of the electromagnetic field generated by the induction coil, i.e., provides a shielding effect. Additionally, the structure improves insulation to ensure that the housing of the aerosol generating device does not get too hot so that a user can handle the device without discomfort. Insulation is the inhibition of heat transfer (the transfer of thermal energy between objects at different temperatures) between objects in thermal contact.

[0008] The heating assembly may further comprise an inductively heatable susceptor disposed around the periphery of the tubular heating section, i.e. a tubular inductively heatable susceptor. In this way, the inductively heatable susceptor may be shaped to surround the aerosol-generating substrate during use. The tubular inductively heatable susceptor may be external to the heating section or may be provided as a wall of the heating section. The tubular inductively heatable susceptor may be internal to the heating section. For example, the tubular inductively heatable susceptor may be provided in an aerosol-generating article intended to be received within the tubular heating section, such that the tubular inductively heatable susceptor surrounds an aerosol-generating substrate provided within the aerosol-generating article.

[0009] The structure may include a second thermal insulation layer disposed inside the first electromagnetic shielding layer, which ensures an optimal alternating electromagnetic field generated by the induction coil and further improves thermal insulation.

[0010] Optionally, the second thermal insulation layer has an outer surface in contact with the inner surface of the first electromagnetic shielding layer.

[0011] The first insulation layer may include one or more sheets of insulating material. The first insulation layer may include air pockets. The air pockets further improve insulation. The first insulation layer may include ceramic fibers, one or more metal oxides, or an aerogel such as Finesulight™. The ceramic fibers may include aluminum oxide, silicon oxide, and / or ZrO2.

[0012] The second insulation layer may include one or more sheets of insulating material. The second insulation layer may include air pockets. The air pockets further improve insulation. The second insulation layer may include ceramic fibers, one or more metal oxides, or an aerogel such as Finesulight™. The ceramic fibers may include aluminum oxide, silicon oxide, and / or ZrO2. The second insulation layer may include a different material than the first insulation layer.

[0013] The first electromagnetic shield layer and the second electromagnetic shield layer may differ in either or both of their electrical conductivity and their magnetic permeability.

[0014] Optionally, one of the first electromagnetic shield layer or the second electromagnetic shield layer includes a ferrimagnetic non-conductive material and the other of the first electromagnetic shield layer or the second electromagnetic shield layer includes a conductive material. Optionally, the first electromagnetic shield layer includes a ferrimagnetic non-conductive material and the second electromagnetic shield layer includes a conductive material. Optionally, the ferrimagnetic non-conductive material includes ferrite, nickel zinc ferrite, or mu metal, and the conductive material includes aluminum, graphite, or copper.

[0015] The second electromagnetic shielding layer may include a mesh.

[0016] The first and second electromagnetic shield layers may be substantially uniformly spaced apart by a distance of 0.5 mm to 1.5 mm, which improves the shielding effectiveness of each of the first and second electromagnetic shield layers.

[0017] The structure may include a third insulation layer disposed outside the first insulation layer. The third insulation layer may include a different material than the first insulation layer (and / or the second insulation layer, if present). Such an arrangement may improve insulation by diffusing heat escaping through the first insulation layer.

[0018] The third insulating layer may include graphite. The third insulating layer may be provided in place of or inside the second electromagnetic shielding layer. Thus, the third insulating layer may have an inner surface in contact with an outer surface of the first insulating layer. The third insulating layer may be provided in addition to or in place of the second insulating layer.

[0019] The structure may include one or more additional electromagnetic shielding layers and / or one or more additional thermal insulation layers. In this manner, the structure may be configured for a variety of applications. In some cases, the structure is configured such that a thermal insulation layer is disposed between any two adjacent electromagnetic shielding layers. In some cases, the structure is configured such that none of the electromagnetic shielding layers contact each other.

[0020] The structure may substantially enclose the heating section, thus maximizing the shielding effect and thermal insulation.

[0021] The structure extends around the circumference of the tubular heating section and may extend over most, preferably the entire, length of the heating section, in this way maximizing the shielding effect and thermal insulation.

[0022] According to a second aspect of the present disclosure, there is provided an aerosol generating device comprising an inductive heating assembly according to any of the above paragraphs.

[0023] According to a third aspect of the present disclosure, there is provided an inductive heating assembly for an aerosol generating device, the inductive heating assembly comprising: a tubular heating section configured to receive an aerosol-generating substrate; A helical induction coil surrounding the tubular heating section; a structure disposed around the helical induction coil; The structure comprises: a first electromagnetic shielding layer, a first thermal insulation layer arranged outside the first electromagnetic shielding layer; a third insulation layer disposed outside the first insulation layer, An induction heating assembly is provided in which a first insulation layer has an inner surface in contact with the outer surface of the first electromagnetic shield layer and an outer surface in contact with the inner surface of the third insulation layer.

[0024] The third aspect of the disclosure may include any of the optional features discussed above in relation to the first aspect of the disclosure. [Brief description of the drawings]

[0025] [Figure 1] FIG. 1 is a schematic cross-sectional view of an aerosol generating device including an induction heating assembly. [Diagram 2] FIG. 2 is a schematic partial cross-sectional view of the aerosol-generating device of FIG. 1, showing an aerosol-generating substrate received in a heating compartment of an induction heating assembly. [Figure 3a] FIG. 3 is a schematic cross-sectional detail view of the circled portion of the aerosol generating device of FIG. 2. [Figure 3b] FIG. 3 is a schematic cross-sectional detail of the circled portion of the aerosol generating device of FIG. 2, although the layers are shown spaced apart, purely for purposes of illustration. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0026] Embodiments of the present disclosure will now be described, by way of example only, and with reference to the accompanying drawings.

[0027] 1 and 2, an example of an aerosol generating device 100 according to the present disclosure is shown in schematic form. The aerosol generating device 100 may equally be referred to as a "heated tobacco device", a "heated non-combustion tobacco device", a "device for vaporizing tobacco products", etc., and is to be interpreted as a device suitable for achieving these effects. The features disclosed herein are equally applicable to devices designed to vaporize any aerosol-generating substrate.

[0028] The aerosol generating device 100 is a handheld, portable device, meaning that a user can hold and support the device in one hand without assistance. The aerosol generating device 100 has a first (or proximal) end 34 and a second (or distal) end 36, and includes a device housing 38.

[0029] In the illustrated example, the aerosol generating device 100 comprises a controller 40. The aerosol generating device 100 may comprise a user interface for controlling the operation of the aerosol generating device 100 via the controller 40.

[0030] The controller 40 is configured to detect the initiation of use of the aerosol generating device 100 in response to a user input, such as pressing a button to activate the aerosol generating device 100, or in response to a detected airflow through the aerosol generating device 100. As will be appreciated by those skilled in the art, the airflow through the aerosol generating device 100 indicates an inhalation or "puff" by a user. The aerosol generating device 100 may include a puff detector, such as, for example, an airflow sensor (not shown), to detect the airflow through the aerosol generating device 100.

[0031] The controller 40 includes an electronic circuit. The aerosol generating device 100 includes a power source 42, such as a battery. The power source 42 and the electronic circuit may be configured to operate at high frequencies. The power source 42 and the electronic circuit may be configured to operate at frequencies of about 80 kHz to 500 kHz, optionally about 150 kHz to 250 kHz, optionally about 200 kHz. The power source 42 and the electronic circuit may also be configured to operate at higher frequencies, for example in the MHz range, if desired.

[0032] The aerosol generating device 100 includes an inductive heating assembly 10. The inductive heating assembly 10 includes a heating section 14. The heating section 14 is configured to receive an aerosol-generating substrate 44. In some examples, the heating section 14 has a generally cylindrical cross-section. The heating section 14 defines a cavity.

[0033] The heating section 14 has a first end 46 and a second end 48. The heating section 14 includes an opening 50 at the first end 46 for receiving the aerosol-generating substrate 44. In the illustrated example, the heating section 14 includes a generally cylindrical sidewall 52, i.e., a sidewall 52 having a generally circular cross-section.

[0034] The aerosol-generating substrate 44 can be any type of solid or semi-solid material. Exemplary types of aerosol-generating solids include powders, granules, pellets, shreds, strands, particles, gels, strips, loose-leaf, cut-leaf, cut filler, porous materials, foamed materials, or sheets. The aerosol-generating substrate 44 can include plant-derived materials, and in particular tobacco. The aerosol-generating substrate 44 can advantageously include reconstituted tobacco.

[0035] The aerosol-generating substrate 44 may include an aerosol-forming agent. Examples of aerosol-forming agents include polyhydric alcohols, such as glycerin or propylene glycol, and mixtures thereof. Typically, the aerosol-generating substrate may include an aerosol-forming agent content of about 5% to about 50% on a dry weight basis. In some examples, the aerosol-generating substrate 44 may include an aerosol-forming agent content of about 10% to about 20% on a dry weight basis, and in some cases about 15% on a dry weight basis.

[0036] When heated, the aerosol-generating substrate 44 may release volatile compounds, which may include flavor compounds, such as nicotine or tobacco flavorings.

[0037] In the illustrated example, the aerosol-generating substrate 44 is included in an aerosol-generating article 54. The shape of the aerosol-generating article 54 corresponds to the shape of the heating section 14. The aerosol-generating article 54 may be generally cylindrical or rod-shaped. The aerosol-generating article may be formed substantially in the shape of a stick, or may generally resemble a cigarette with a tubular region with the aerosol-generating substrate 44 arranged in a suitable configuration. The aerosol-generating article 54 is a disposable and replaceable article, and may, for example, contain tobacco as the aerosol-generating substrate 44. The aerosol-generating article 54 has a first end 56 (or mouth end) and a second end 58, and includes a filter 60 at the first end 56. The filter 60 functions as a mouthpiece and may include a breathable plug, for example a breathable plug including cellulose acetate fibers.

[0038] The aerosol-generating substrate 44 and filter 60 may be surrounded by a paper wrapper and thus embodied as an aerosol-generating article 54. Some designs may also include one or more vapor collection regions, cooling regions, and other structures.

[0039] To use the aerosol generating device 100, a user inserts the aerosol-generating article 54 into the heating section 14 through the opening 50 such that the second end 58 of the aerosol-generating article 54 is positioned at the second end 48 of the heating section 14 and the filter 60 at the first end 56 of the aerosol-generating article 54 protrudes from the first end 46 of the heating section 14 so that the user can hold it between their lips.

[0040] The induction heating assembly 10 further comprises an induction coil 12. The induction coil 12 is configured to be energized to generate an alternating electromagnetic field for inductively heating an inductively heatable susceptor 62. The inductively heatable susceptor 62 may be disposed around the periphery of the heating section 14 as shown, or alternatively may be disposed to protrude from the second end 48 into the heating section 14 (e.g., as a heating blade or pin) and penetrate the aerosol-generating substrate 44, or may be provided to the aerosol-generating substrate 44 during manufacture of the aerosol-generating article 54. The inductively heatable susceptor 62 may be tubular and surround the aerosol-generating substrate 44.

[0041] During use, heat from the inductively heatable susceptor 62 is transferred, for example by conduction, radiation, and convection, to the aerosol-generating substrate 44 of the aerosol-generating article 54 disposed in the heating section 14 to heat the aerosol-generating substrate 44 (without combusting the aerosol-generating substrate 44), thereby generating vapor which cools and condenses to form an aerosol for inhalation, such as through a filter 60, by a user of the aerosol-generating device 100. Evaporation of the aerosol-generating substrate 44 is aided by the addition of air from the surrounding environment, for example through an air inlet (not shown).

[0042] Generally speaking, a vapor is a substance that is in the gas phase below its critical temperature, meaning that the vapor can be condensed into a liquid by increasing the pressure without decreasing the temperature. An aerosol, on the other hand, is a suspension of fine solid particles or liquid droplets in air or another gas. However, it should be noted that the terms "aerosol" and "vapor" may be used interchangeably herein, particularly with respect to the form of inhalable medium that is generated for inhalation by a user.

[0043] The induction coil 12 may be energized by a power supply 42 and a controller 40. The induction coil 12 may comprise Litz wire or Litz cable; however, it should be understood that other materials may be used. In the illustrated example, the induction coil 12 extends around the heating section 14.

[0044] In the illustrated example, the induction coil 12 extends around the heating section 14. Thus, the induction coil 12 is annular. In the illustrated example, the induction coil 12 is generally helical in shape. In some examples, the circular cross-section of the helical induction coil 12 may facilitate insertion of the aerosol-generating substrate 44, or an aerosol-generating article 54, for example, including the aerosol-generating substrate 44, and optionally one or more inductively heatable susceptors 62, into the heating section 14 to ensure uniform heating of the aerosol-generating substrate 44.

[0045] In the illustrated example, the inductively heatable susceptor 62 comprises an electrically conductive material. The inductively heatable susceptor 62 may comprise, but is not limited to, one or more of graphite, molybdenum, silicon carbide, niobium, aluminum, iron, nickel, nickel-containing compounds, titanium, mild steel, stainless steel, low carbon steel, and alloys thereof, such as nickel chromium or nickel copper, and composites of metallic materials. In some examples, the inductively heatable susceptor 62 comprises a metal selected from the group consisting of mild steel, stainless steel, and low carbon stainless steel.

[0046] During use, application of an electromagnetic field in the vicinity of the susceptor 62 can cause the susceptor 62 to generate heat due to eddy currents and magnetic hysteresis losses resulting in electromagnetic-to-thermal energy conversion.

[0047] The induction coil 12 may be configured, in use, to operate with a varying electromagnetic field having a magnetic flux density of about 20 mT to about 2.0 T (at the point of highest density).

[0048] The induction heating assembly 10 further comprises a structure 16 disposed about the induction coil 12. Thus, the structure 16 is disposed outside the induction coil 12. In the illustrated example, the structure 16 substantially surrounds the induction coil 12.

[0049] In the illustrated example, the structure 16 substantially surrounds the heating section 14. The heating section 14 is tubular. Thus, the susceptor 62 disposed around the periphery of the heating section 14 is also tubular. In the illustrated example, the structure 16 extends around the outer periphery of the tubular heating section 14 and extends over most, and preferably the entire, length of the heating section 14. In this manner, the shielding effect and thermal insulation are maximized.

[0050] In the illustrated example, structure 16 is generally cylindrical, e.g., in the form of a generally cylindrical sleeve disposed radially outwardly of induction coil 12 so as to extend circumferentially around induction coil 12. Thus, in the illustrated example, structure 16 is disposed circumferentially around induction coil 12.

[0051] Figures 3a and 3b show detailed views of the structure 16. In the illustrated example, the structure 16 comprises an arrangement of several layers. In Figure 3b, the layers are shown spaced apart purely for illustration purposes. With reference to Figures 3a and 3b, the structure 16 comprises a first electromagnetic shielding layer 18 and a second electromagnetic shielding layer 20. The second electromagnetic shielding layer 20 is arranged outside the first electromagnetic shielding layer 18. The first electromagnetic shielding layer 18 and the second electromagnetic shielding layer 20 may differ in either or both of their electrical conductivity and their magnetic permeability.

[0052] First electromagnetic shield layer 18 is typically formed from a ferrimagnetic, non-conductive material such as ferrite, nickel zinc ferrite, or mu-metal.

[0053] The first electromagnetic shield layer 18 may include a laminate structure and thus may itself include multiple layers. The layers may include the same material or may include multiple different materials, for example selected to provide desired shielding properties. The first electromagnetic shield layer 18 may include, for example, one or more ferrite layers and one or more adhesive layers.

[0054] The first electromagnetic shield layer 18 may have a thickness of 0.1 mm to 10 mm. In some examples, the thickness may be 0.1 mm to 6 mm, and more preferably, the thickness may be 0.7 mm to 2.0 mm.

[0055] The second electromagnetic shield layer 20 typically comprises a conductive material, for example a metal such as aluminum or copper, and may be in the form of a mesh.

[0056] The second electromagnetic shield layer 20 may comprise a laminate structure and thus may itself comprise multiple layers. The layers may comprise the same material or may comprise multiple different materials, for example selected to provide desired shielding properties.

[0057] The second electromagnetic shield layer 20 may have a thickness of 0.1 mm to 0.5 mm. In some examples, the thickness may be 0.1 mm to 0.2 mm.

[0058] The resistance value of the second electromagnetic shield layer 20 is selected to minimize heating losses and conductive losses in the second electromagnetic shield layer 20. The resistance value of the second electromagnetic shield layer 20 may be, for example, less than 30 mΩ. In some examples, the resistance value may be less than 15 mΩ, or less than 10 mΩ.

[0059] The structure 16 further includes a first insulation layer 22 disposed between the first electromagnetic shielding layer 18 and the second electromagnetic shielding layer 20. The first insulation layer 22 has an inner surface 26 that contacts an outer surface 28 of the first electromagnetic shielding layer 18. The first insulation layer 22 has an outer surface 30 that contacts an inner surface 32 of the second electromagnetic shielding layer 20. The first insulation layer 22 may be encapsulated between the first electromagnetic shielding layer 18 and the second electromagnetic shielding layer 20.

[0060] In the illustrated example, the first electromagnetic shield layer 18 and the second electromagnetic shield layer 20 are spaced apart substantially uniformly. The first electromagnetic shield layer 18 and the second electromagnetic shield layer 20 are spaced apart substantially uniformly by the first thermal insulation layer 22. The distance separating the first electromagnetic shield layer 18 and the second electromagnetic shield layer 20 may be 0.5 mm to 1.5 mm. This degree of spacing improves the shielding effect of each of the first electromagnetic shield layer 18 and the second electromagnetic shield layer 20. This distance corresponds to the thickness of the first thermal insulation layer 22. Thus, the first thermal insulation layer 22 has a uniform thickness of 0.5 mm to 1.5 mm.

[0061] In the illustrated example, the structure 16 further includes a second insulating layer 24. The second insulating layer 24 is disposed inside the first electromagnetic shielding layer 18. The structure 16 is configured such that the second insulating layer 24 is adjacent to the induction coil 12. Such a configuration ensures that an optimal alternating electromagnetic field is generated by the induction coil 12.

[0062] In the illustrated example, second insulation layer 24 has an outer surface 64 that contacts an inner surface 66 of first electromagnetic shield layer 18. Thus, second insulation layer 24 contacts first electromagnetic shield layer 18. First electromagnetic shield layer 18 also contacts first insulation layer 22. First insulation layer 22 also contacts second electromagnetic shield layer 20.

[0063] First insulation layer 22 and / or second insulation layer 24 may, for example, comprise a laminated or composite structure, and thus may each comprise multiple layers and / or mixtures of particles / elements. The layers or mixtures of particles / elements may comprise the same material or multiple different materials.

[0064] The first and second insulating layers 22, 24 may include one or more sheets of insulating material. The first and second insulating layers 22, 24 may include Superwool™, which is a ceramic fiber. The ceramic fiber may include aluminum oxide, silicon oxide, and / or ZrO2. In other examples, the first and / or second insulating layers 22, 24 may alternatively or additionally include one or more metal oxides, or an aerogel. The first and second insulating layers 22, 24 may include Finesulight™, which is a type of aerogel.

[0065] The first insulation layer 22 and / or the second insulation layer 24 may include air pockets. Air pockets are internal structures contained within the material of the first insulation layer 22 and / or the second insulation layer 24. For example, in the case of Superwool™, the internal structures are defined between the ceramic fibers. The air pockets hold air that contributes to and thus improves insulation.

[0066] In some examples, a third insulating layer may be provided inside the second electromagnetic shielding layer or instead of the second electromagnetic shielding layer. The third insulating material may include a material such as graphite that is effective for heat diffusion. When referring to a third insulating layer, the presence of a second insulating layer is not necessarily implied. That is, some examples may provide a layered structure including a first electromagnetic shielding layer, a first insulating layer, and a third insulating layer. The first electromagnetic shielding layer may be encapsulated by the first insulating layer, and the first insulating layer may be encapsulated by the third insulating layer. An example of such a three-layer structure may include ferrite (for shielding), Finesulight™ (for insulation), and graphite (for hot spot suppression).

[0067] In some examples, the structure 16 may include one or more additional electromagnetic shielding layers 18, 20 and / or one or more additional thermal insulation layers 22, 24. In this manner, the structure 16 may be configured for a variety of applications. In such examples, the structure 16 is configured such that a thermal insulation layer is disposed between any two adjacent electromagnetic shielding layers. The structure 16 is configured such that none of the electromagnetic shielding layers contact one another.

[0068] Structure 16 includes multiple layers and is therefore a laminate structure.

[0069] A structure 16 having the configuration disclosed above reduces leakage of the electromagnetic field generated by the induction coil 12. Furthermore, such a structure 16 improves insulation to ensure that the housing 38 (i.e., casing) of the aerosol generating device 100 does not become too hot so that a user can handle the aerosol generating device 100 without discomfort. Insulation is the inhibition of heat transfer (transfer of thermal energy between objects at different temperatures) between objects in thermal contact.

[0070] Although exemplary embodiments have been described in the preceding paragraphs, it should be understood that various modifications can 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.

[0071] Any combination of the above-described features in all possible variations thereof is encompassed by the present disclosure unless otherwise indicated herein or clearly contradicted by context.

[0072] Unless the context clearly dictates otherwise, throughout this specification and the claims, the words "comprise", "comprising", and the like are to be construed in an inclusive sense, i.e., "including but not limited to", rather than in an exclusive or exhaustive sense.

Claims

1. An induction heating assembly (10) for an aerosol generating device (100), wherein the induction heating assembly (10) comprises: A tubular heating section (14) configured to receive an aerosol generating substrate; A helical induction coil (12) surrounding the tubular heating section; A structure (16) disposed around the helical induction coil (12), comprising: The structure (16) comprises: A first electromagnetic shielding layer (18); A second electromagnetic shielding layer (20) disposed outside the first electromagnetic shielding layer (18); A first heat insulating layer (22) disposed between the first electromagnetic shielding layer (18) and the second electromagnetic shielding layer (20); including; The first heat insulating layer (22) has an inner surface (26) in contact with an outer surface (28) of the first electromagnetic shielding layer (18) and an outer surface (30) in contact with an inner surface (32) of the second electromagnetic shielding layer (20). Induction heating assembly (10).

2. The induction heating assembly according to claim 1, further comprising an induction heatable susceptor disposed around the periphery of the tubular heating section.

3. The induction heating assembly according to claim 1, wherein the structure (16) comprises a second heat insulating layer (24) disposed inside the first electromagnetic shielding layer (18).

4. The induction heating assembly according to claim 1, wherein the first heat insulating layer (22) comprises one or more sheets of heat insulating material.

5. The induction heating assembly according to claim 1, wherein the first heat insulating layer (22) comprises air pockets.

6. The first heat insulating layer (22) comprises ceramic fibers, one or more metal oxides, or aerogels, and the ceramic fibers are optionally aluminum oxide, silicon oxide, and / or ZrO ２The induction heating assembly according to claim 1, comprising **Claim 7** The induction heating assembly according to claim 1, wherein one or both of the conductivity and the magnetic permeability of the first electromagnetic shielding layer (18) and the second electromagnetic shielding layer (20) are different. **Claim 8** The induction heating assembly according to claim 1, wherein one of the first electromagnetic shielding layer (18) or the second electromagnetic shielding layer (20) contains a ferromagnetic non-conductive material, and the other of the first electromagnetic shielding layer (18) or the second electromagnetic shielding layer (20) contains a conductive material. **Claim 9** The induction heating assembly according to claim 1, wherein the first electromagnetic shielding layer (18) contains a ferromagnetic non-conductive material, and the second electromagnetic shielding layer (20) contains a conductive material. **Claim 10** The induction heating assembly according to claim 8, wherein the ferromagnetic non-conductive material contains ferrite, nickel-zinc ferrite, or mu-metal, and the conductive material contains aluminum, graphite, or copper. **Claim 11** The induction heating assembly according to claim 1, wherein the second electromagnetic shielding layer (20) includes a mesh. **Claim 12** The induction heating assembly according to claim 1, wherein the first electromagnetic shielding layer (18) and the second electromagnetic shielding layer (20) are arranged at a substantially uniform distance of 0.5 mm to 1.5 mm apart. **Claim 13** The induction heating assembly according to claim 1, wherein the structure (16) substantially surrounds the tubular heating section (14). **Claim 14** The induction heating assembly according to claim 1, wherein the structure (16) includes one or more additional electromagnetic shielding layers (18, 20) and / or one or more additional heat insulation layers (22, 24). **Claim 15** An aerosol generating device (100) comprising the induction heating assembly (10) according to any one of claims 1 to 14.

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