Induction heating assembly for aerosol generating device

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 generally relates to an induction heating assembly for an aerosol generating device, and more particularly to an induction 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 aerosol generating devices.

Background Art

[0002] In recent years, devices that heat an aerosol generating substrate rather than burning it to generate an aerosol for inhalation have become popular among consumers.

[0003] Such devices may use one of several different techniques for providing heat to the substrate. One such technique is to provide an aerosol generating device that employs an induction heating system including an inductor.

[0004] When a user operates the device, electrical energy is supplied to the inductor, thereby generating an alternating electromagnetic field. The susceptor couples with the electromagnetic field to generate heat, and the heat is transmitted to the substrate, for example, by conduction. When the substrate is heated, an aerosol for the user of the device to inhale is generated.

Summary of the Invention

Problems to be Solved by the Invention

[0005] A disadvantage of using an induction heating system is that electromagnetic field leakage may occur. Further, the housing of the device may become hot due to the generated heat. Therefore, it is necessary to address these disadvantages.

Means for Solving the Problems

[0006] According to a first aspect of the present disclosure, an induction heating assembly for an aerosol generating device, the induction heating assembly comprising A tubular heating compartment configured to receive an aerosol generating substrate, • A helical induction coil surrounding a tubular heating section, It has a structure arranged around a helical induction coil, The aforementioned structure is - The first electromagnetic shielding layer, - A second electromagnetic shielding layer is positioned outside the first electromagnetic shielding layer, -A first thermal insulation layer is placed between the first electromagnetic shielding layer and the second electromagnetic shielding layer, Includes, An induction heating assembly is provided, wherein the first insulating layer has an inner surface that contacts the outer surface of the first electromagnetic shielding layer and an outer surface that contacts the inner surface of the second electromagnetic shielding layer.

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

[0008] The heating assembly may further comprise an inductively heatable susceptor, i.e., a tubular inductively heatable susceptor, positioned around the periphery of a tubular heating compartment. In this way, the inductively heatable susceptor may be shaped to surround an aerosol-generating substrate during use. The tubular inductively heatable susceptor may be located outside the heating compartment, or it may be provided as a wall of the heating compartment. The tubular inductively heatable susceptor may be located inside the heating compartment. For example, the tubular inductively heatable susceptor may be provided in an aerosol-generating article intended to be received within a tubular heating compartment, so 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 positioned inside the first electromagnetic shielding layer. This arrangement ensures that the induction coil generates an optimal alternating electromagnetic field and further improves thermal insulation.

[0010] In some cases, the second insulating layer has an outer surface that is in contact with the inner surface of the first electromagnetic shielding layer.

[0011] The first insulation layer may include one or more sheets of insulation 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 from the first insulation layer.

[0013] The first electromagnetic shielding layer and the second electromagnetic shielding layer may differ in either their conductivity or their permeability, or both.

[0014] In some cases, one of the first or second electromagnetic shielding layers includes a ferrimagnetic nonconductive material, and the other of the first or second electromagnetic shielding layer includes a conductive material. In some cases, the first electromagnetic shielding layer includes a ferrimagnetic nonconductive material, and the second electromagnetic shielding layer includes a conductive material. In some cases, the ferrimagnetic nonconductive 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 electromagnetic shielding layer and the second electromagnetic shielding layer can be spaced substantially uniformly apart by a distance of 0.5 mm to 1.5 mm. This spacing improves the shielding effect of each of the first and second electromagnetic shielding layers.

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

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

[0019] The structure may comprise one or more additional electromagnetic shielding layers and / or one or more additional thermal insulation layers. Thus, the structure can be configured for a variety of applications. In some cases, the structure is configured such that a thermal insulation layer is placed between any two adjacent electromagnetic shielding layers. In some cases, the structure is configured so that no electromagnetic shielding layers come into contact with each other.

[0020] The structure can substantially enclose the heated area. In this way, shielding and thermal insulation are maximized.

[0021] The structure extends around the outer periphery of the tubular heating compartment and may extend over most of the length of the heating compartment, preferably the entire length. In this way, shielding and heat insulation are maximized.

[0022] A second aspect of the present disclosure provides an aerosol generating device comprising an induction heating assembly as described in any of the above paragraphs.

[0023] According to a third aspect of the present disclosure, an induction heating assembly for an aerosol generating device, the induction 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, wherein the structure - a first electromagnetic shielding layer; - a first heat insulating layer disposed outside the first electromagnetic shielding layer; - a third heat insulating layer disposed outside the first heat insulating layer, and the first heat insulating layer has an inner surface in contact with the outer surface of the first electromagnetic shielding layer and an outer surface in contact with the inner surface of the third heat insulating layer, and an induction heating assembly is provided.

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

Brief Description of the Drawings

[0025] [Figure 1] It is a schematic cross-sectional view of an aerosol generating device provided with an induction heating assembly. [Figure 2] It is a schematic partial cross-sectional view showing the aerosol generating device of FIG. 1 with the aerosol generating substrate received in the heating section of the induction heating assembly. [Figure 3a] It is a schematic cross-sectional detail view of the circled portion of the aerosol generating device of FIG. 2. [Figure 3b] It is a schematic cross-sectional detail view of the circled portion of the aerosol generating device of FIG. 2. However, purely for illustrative purposes, the layers are shown spaced apart.

Embodiments for Carrying Out the Invention

[0026] Here, by way of mere example and with reference to the accompanying drawings, embodiments of the present disclosure will be described.

[0027] First, referring to Figures 1 and 2, an example of the aerosol generating device 100 according to this disclosure is schematically shown. The aerosol generating device 100 can be referred to as a "heated tobacco device," a "heated non-combustion tobacco device," a "tobacco product vaporization device," etc., and is 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 the user can hold and support the device with one hand without assistance. The aerosol generating device 100 has a first (or proximal) end 34 and a second (or distal) end 36, and comprises a device housing 38.

[0029] In the illustrated example, the aerosol generating device 100 includes a controller 40. The aerosol generating device 100 may also include 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 start of use of the aerosol generating device 100 in response to user input, such as pressing a button to activate the aerosol generating device 100, or in response to the detected airflow passing through the aerosol generating device 100. As will be understood by those skilled in the art, the airflow passing through the aerosol generating device 100 indicates inhalation or "puffing" by the user. The aerosol generating device 100 may be equipped with a puff detector, such as an airflow sensor (not shown), to detect the airflow passing through the aerosol generating device 100.

[0031] The controller 40 includes electronic circuitry. The aerosol generating device 100 includes a power supply 42, such as a battery. The power supply 42 and electronic circuitry may be configured to operate at high frequencies. The power supply 42 and electronic circuitry may be configured to operate at frequencies of approximately 80 kHz to 500 kHz, optionally approximately 150 kHz to 250 kHz, and optionally approximately 200 kHz. The power supply 42 and electronic circuitry may also be configured to operate at higher frequencies, such as in the MHz band, as needed.

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

[0033] The heating section 14 has a first end 46 and a second end 48. The heating section 14 is provided with an opening 50 at the first end 46 for receiving the aerosol generating substrate 44. In the illustrated example, the heating section 14 is provided with a substantially cylindrical side wall 52, that is, a side wall 52 having a substantially circular cross-section.

[0034] The aerosol generating substrate 44 may be any type of solid or semi-solid material. Exemplary types of aerosol generating solids include powders, granules, pellets, shredded, strands, particles, gels, strips, loose leaves, cut leaves, cut fillers, porous materials, foamed materials, or sheets. The aerosol generating substrate 44 may include plant-derived materials, particularly tobacco. Advantageously, the aerosol generating substrate 44 may include reconstituted tobacco.

[0035] The aerosol generating substrate 44 may contain 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 contain 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 contain an aerosol forming agent content of about 10% to about 20%, and in some cases about 15%, on a dry weight basis.

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

[0037] In the illustrated example, the aerosol generating substrate 44 is contained within the 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 substantially cylindrical or rod-shaped. The aerosol generating article may be formed substantially in the shape of a stick and may generally resemble a cigarette having a tubular region with an aerosol generating substrate 44 arranged in a preferred form. The aerosol generating article 54 is a disposable and replaceable article and may contain, for example, a cigarette as the aerosol generating substrate 44. The aerosol generating article 54 has a first end 56 (or mouth end) and a second end 58, with a filter 60 provided at the first end 56. The filter 60 functions as a mouthpiece and may include a breathable plug, such as a breathable plug containing cellulose acetate fibers.

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

[0039] To use the aerosol generating device 100, the user inserts the aerosol generating article 54 into the heating compartment 14 through the opening 50, so that the second end 58 of the aerosol generating article 54 is positioned at the second end 48 of the heating compartment 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 compartment 14, allowing the user to hold it in their mouth.

[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 induction-heatable susceptor 62. The induction-heatable susceptor 62 may be positioned around the periphery of the heating section 14 as shown in the figure, or it may be positioned to protrude into the heating section 14 from a second end 48 (for example, as a heating blade or pin) and penetrate the aerosol-generating substrate 44), or it may be provided on the aerosol-generating substrate 44 during the manufacture of the aerosol-generating article 54. The induction-heatable susceptor 62 is tubular and may surround the aerosol-generating substrate 44.

[0041] During use, heat from the induction-heatable susceptor 62 is transferred, for example by conduction, radiation, and convection, to the aerosol-generating substrate 44 of the aerosol-generating article 54 located in the heating compartment 14, thereby heating the aerosol-generating substrate 44 (without burning the aerosol-generating substrate 44) and generating vapor, which is then cooled and condensed to form an aerosol for the user of the aerosol-generating device 100 to inhale through the filter 60, etc. The evaporation of the aerosol-generating substrate 44 is facilitated by adding air from the ambient environment, for example, through an air inlet (not shown).

[0042] Generally speaking, vapor is a substance that exists in the gaseous phase at temperatures below its critical temperature, meaning that vapor can be condensed into a liquid by increasing the pressure without decreasing the temperature. Aerosol, on the other hand, is a mixture of fine solid particles or droplets suspended in the air or another gas. However, it should be noted that in this specification, the terms “aerosol” and “vapor” may be used interchangeably, particularly in reference to the form of an inhalable medium generated for the user to inhale.

[0043] The induction coil 12 can be energized by the power supply 42 and the controller 40. The induction coil 12 may be made of Litz wire or Litz cable. However, it should be understood that other materials may also be used. In the illustrated example, the induction coil 12 extends around the heating compartment 14.

[0044] In the illustrated example, the induction coil 12 extends around the heating compartment 14. Therefore, 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 facilitates the insertion of the aerosol generating substrate 44, or for example, an aerosol generating article 54 containing the aerosol generating substrate 44, and optionally one or more induction-heatable susceptors 62, into the heating compartment 14, thereby ensuring uniform heating of the aerosol generating substrate 44.

[0045] In the illustrated example, the induction-heatable susceptor 62 includes a conductive material. The induction-heatable susceptor 62 may include, but is not limited to, one or more of the following: 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 composite materials of metallic materials. In some examples, the induction-heatable susceptor 62 includes a metal selected from the group consisting of mild steel, stainless steel, and low-carbon stainless steel.

[0046] During use, if an electromagnetic field is applied near the susceptor 62, the susceptor 62 may generate heat due to the conversion of electromagnetic energy into heat caused by eddy currents and magnetic hysteresis losses.

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

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

[0049] In the illustrated example, the structure 16 substantially encloses the heating compartment 14. The heating compartment 14 is tubular. Therefore, the susceptor 62 positioned around the periphery of the heating compartment 14 is also tubular. In the illustrated example, the structure 16 extends around the outer circumference of the tubular heating compartment 14, extending over most of the length of the heating compartment 14, preferably the entire length. In this way, the shielding effect and thermal insulation are maximized.

[0050] In the illustrated example, the structure 16 is substantially cylindrical, for example, in the form of a substantially cylindrical sleeve positioned radially outward of the induction coil 12 so as to extend circumferentially around the induction coil 12. Therefore, in the illustrated example, the structure 16 is positioned circumferentially around the induction coil 12.

[0051] Figures 3a and 3b show detailed views of the structure 16. In the illustrated example, the structure 16 includes a configuration consisting of several layers. In Figure 3b, the layers are shown spaced apart purely for illustrative purposes. Referring 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 located outside the first electromagnetic shielding layer 18. The first electromagnetic shielding layer 18 and the second electromagnetic shielding layer 20 may differ in either their conductivity or their permeability, or both.

[0052] The first electromagnetic shielding layer 18 is typically formed from a ferrimagnetic nonconductive material such as ferrite, nickel-zinc ferrite, or mu-metal.

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

[0054] The first electromagnetic shielding 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 shielding layer 20 typically comprises a conductive material, such as a metal like aluminum or copper, and may be in the form of a mesh.

[0056] The second electromagnetic shielding layer 20 may include a laminated structure and therefore may include multiple layers. The layers may contain the same material or may contain multiple different materials selected, for example, to provide desired shielding properties.

[0057] The second electromagnetic shielding 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 of the second electromagnetic shielding layer 20 is selected to minimize heating losses and conductivity losses in the second electromagnetic shielding layer 20. The resistance of the second electromagnetic shielding layer 20 may be, for example, less than 30 mΩ. In some examples, the resistance may be less than 15 mΩ, or less than 10 mΩ.

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

[0060] In the illustrated example, the first electromagnetic shielding layer 18 and the second electromagnetic shielding layer 20 are arranged with substantially uniform spacing between them. The first electromagnetic shielding layer 18 and the second electromagnetic shielding layer 20 are arranged with substantially uniform spacing between them by the first thermal insulation layer 22. The distance separating the first electromagnetic shielding layer 18 and the second electromagnetic shielding layer 20 can be between 0.5 mm and 1.5 mm. This spacing improves the shielding effect of each of the first electromagnetic shielding layer 18 and the second electromagnetic shielding layer 20. This distance corresponds to the thickness of the first thermal insulation layer 22. Therefore, the first thermal insulation layer 22 has a uniform thickness of between 0.5 mm and 1.5 mm.

[0061] In the illustrated example, the structure 16 further comprises a second thermal insulation layer 24. The second thermal insulation layer 24 is located inside the first electromagnetic shielding layer 18. The structure 16 is configured such that the second thermal insulation layer 24 is adjacent to the induction coil 12. This configuration ensures that the induction coil 12 generates an optimal alternating electromagnetic field.

[0062] In the illustrated example, the second thermal insulation layer 24 has an outer surface 64 that contacts the inner surface 66 of the first electromagnetic shielding layer 18. Thus, the second thermal insulation layer 24 is in contact with the first electromagnetic shielding layer 18. The first electromagnetic shielding layer 18 is also in contact with the first thermal insulation layer 22. The first thermal insulation layer 22 is also in contact with the second electromagnetic shielding layer 20.

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

[0064] The first insulation layer 22 and the second insulation layer 24 may comprise one or more sheets of insulation material. The first insulation layer 22 and the second insulation layer 24 may comprise Superwool®, which is a ceramic fiber. The ceramic fiber may comprise aluminum oxide, silicon oxide, and / or ZrO2. In other examples, the first insulation layer 22 and / or the second insulation layer 24 may optionally or additionally comprise one or more metal oxides or aerogels. The first insulation layer 22 and the second insulation layer 24 may comprise Finesulight®, which is a type of aerogel.

[0065] The first insulation layer 22 and / or the second insulation layer 24 may include air pockets. These 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 Superwool®, these internal structures are defined between ceramic fibers. The air pockets hold air that contributes to and, consequently, improves insulation.

[0066] In some examples, a third insulation layer may be provided inside the second electromagnetic shielding layer, or in place of the second electromagnetic shielding layer. The third insulation material may include a material such as graphite that is effective in heat diffusion. When referring to a third insulation layer, the presence of a second insulation layer is not necessarily assumed. That is, some examples may provide a layered structure comprising a first electromagnetic shielding layer, a first insulation layer, and a third insulation layer. The first electromagnetic shielding layer may be wrapped by the first insulation layer, and the first insulation layer may be wrapped by the third insulation 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 comprise one or more additional electromagnetic shielding layers 18, 20 and / or one or more additional thermal insulation layers 22, 24. Thus, the structure 16 can be configured for a variety of applications. In such examples, the structure 16 is configured such that a thermal insulation layer is placed between any two adjacent electromagnetic shielding layers. The structure 16 is configured so that no electromagnetic shielding layers come into contact with each other.

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

[0069] The 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 thermal insulation so that the housing 38 (i.e., casing) of the aerosol generating device 100 does not become hot, so that the user can handle the aerosol generating device 100 without discomfort. Thermal insulation is the suppression of heat transfer (transfer of thermal energy between objects with different temperatures) between objects in thermal contact.

[0070] While exemplary embodiments have been described in the preceding paragraphs, various modifications to these embodiments are naturally possible without departing from the scope of the attached claims. Therefore, the breadth and scope of the claims should not be limited to the exemplary embodiments described above.

[0071] Unless otherwise stated herein or unless clearly inconsistent with the context, any combination of any possible variations thereof of the features described above is encompassed by this disclosure.

[0072] Unless the context clearly indicates otherwise, throughout this specification and the claims, words such as “includes” and “contains” should be interpreted in an inclusive sense, i.e., “includes, 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) is A tubular heating section (14) configured to receive an aerosol generating substrate, A helical induction coil (12) surrounds the tubular heating section, The structure (16) is arranged along the circumferential direction of the helical induction coil (12) so as to surround the helical induction coil (12), The structure (16) extends radially outward from the helical induction coil (12), A second heat insulating layer (24) is positioned adjacent to the helical induction coil (12), The first electromagnetic shielding layer (18) is positioned outside the second thermal insulation layer (24), A first heat insulating layer (22) is disposed on the outside of the first electromagnetic shielding layer (18), A second electromagnetic shielding layer (20) is disposed on the outside of the first thermal insulation layer (22), Includes, The first electromagnetic shielding layer (18) comprises a ferrimagnetic nonconductive material. The second electromagnetic shielding layer (20) comprises a conductive material, The first heat insulating layer (22) has an inner surface (26) that contacts the outer surface (28) of the first electromagnetic shielding layer (18) and an outer surface (30) that contacts the inner surface (32) of the second electromagnetic shielding layer (20). The induction heating assembly (10) has an outer surface (64) that contacts the inner surface (66) of the first electromagnetic shielding layer (18) of the second insulating layer (24).

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 first insulating layer (22) comprises one or more sheets of insulating material.

4. The induction heating assembly according to claim 1, wherein the first insulating layer (22) includes an air pocket.

5. The first insulating layer (22) comprises ceramic fibers, one or more metal oxides, or aerogel, wherein the ceramic fibers are optionally aluminum oxide, silicon oxide, and / or ZrO ２ The induction heating assembly according to claim 1, comprising:

6. The induction heating assembly according to claim 1, wherein the first electromagnetic shielding layer (18) and the second electromagnetic shielding layer (20) differ in one or both of their conductivity and / or magnetic permeability.

7. The induction heating assembly according to claim 1, wherein the ferrimagnetic nonconductive material includes ferrite, nickel-zinc ferrite, or mu-metal, and the conductive material includes aluminum, graphite, or copper.

8. The induction heating assembly according to claim 1, wherein the second electromagnetic shielding layer (20) includes a mesh.

9. The induction heating assembly according to claim 1, wherein the first electromagnetic shielding layer (18) and the second electromagnetic shielding layer (20) are arranged substantially uniformly with a distance of 0.5 mm to 1.5 mm between them.

10. The induction heating assembly according to claim 1, wherein the structure (16) substantially surrounds the tubular heating compartment (14).

11. The induction heating assembly according to claim 1, wherein the structure (16) comprises one or more further electromagnetic shielding layers (18, 20) and / or one or more further heat insulating layers (22, 24).

12. An aerosol generating device (100) comprising an induction heating assembly (10) according to any one of claims 1 to 11.

Images