CN115918971A

CN115918971A - Gas mist generating device and heater for gas mist generating device

Info

Publication number: CN115918971A
Application number: CN202110888333.2A
Authority: CN
Inventors: 张淑媛; 徐中立; 李永海
Original assignee: Shenzhen FirstUnion Technology Co Ltd
Current assignee: Shenzhen FirstUnion Technology Co Ltd
Priority date: 2021-08-03
Filing date: 2021-08-03
Publication date: 2023-04-07

Abstract

The application provides an aerosol-generating device and a heater for the aerosol-generating device; wherein the aerosol-generating device comprises: a receiving cavity; a susceptor extending at least partially within the receiving cavity and configured to be penetrated by a varying magnetic field to generate heat; the susceptor has a holding chamber extending in an axial direction; an induction coil located within the holding cavity of the susceptor and configured to generate a varying magnetic field; a magnetic core at least partially positioned within the induction coil. The above aerosol-generating device absorbs the magnetic field or lines of force inside and outside the induction coil through the susceptor and the magnetic core, respectively, and is advantageous for preventing or reducing the leakage flux.

Description

Gas mist generating device and heater for gas mist generating device

Technical Field

The embodiment of the application relates to aerosol generation technical field, especially relates to an aerosol generation device and be used for aerosol generation device's heater.

Background

Smoking articles (e.g., cigarettes, cigars, etc.) burn tobacco during use to produce tobacco smoke. Attempts have been made to replace these tobacco-burning products by making products that release compounds without burning.

An example of such a product is a heating device, as shown in fig. 1, in which a magnetic field is generated by means of an induction coil 1 and heat is induced by means of a susceptor 2 arranged in the coil, thereby heating the tobacco product. Only part of the magnetic field generated by the induction coil 1 in such a heating device is absorbed by the susceptor 2 and there is a leakage flux.

Disclosure of Invention

An embodiment of the present application provides an aerosol-generating device for heating an aerosol-generating article to generate an aerosol; the method comprises the following steps:

a receiving chamber for receiving an aerosol-generating article;

a susceptor extending at least partially within the receiving cavity and configured to be penetrated by a varying magnetic field to generate heat to heat an aerosol-generating article received in the receiving cavity; the susceptor has a holding cavity extending in an axial direction;

an induction coil located within a holding cavity of the susceptor and configured to generate a varying magnetic field;

a magnetic core at least partially located within the induction coil.

In a preferred implementation, the magnetic core comprises at least any one of iron, cobalt or nickel.

In a preferred implementation, the magnetic core comprises an iron-aluminum alloy.

In a preferred implementation, the mass percent of aluminum in the iron-aluminum alloy is 8-20%.

In a preferred embodiment, a projection of the magnetic core in the axial direction of the induction coil covers the hollow of the induction coil.

In a preferred implementation, the induction coil includes axially opposed first and second ends; the magnetic core penetrates from the first end to the second end of the induction coil.

In a preferred implementation, the magnetic core comprises a first portion extending in an axial direction of the induction coil; the extension length of the first part along the axial direction of the induction coil is greater than or equal to the extension length of the induction coil.

In a preferred implementation, the first portion is substantially elongate and rod-like.

In a preferred implementation, the magnetic core includes a second portion exposed outside the induction coil;

the cross-sectional area of the hollow of the induction coil is less than or equal to the cross-sectional area of the second portion.

In a preferred implementation, the second portion is arranged to abut against one of the ends of the induction coil in the axial direction.

In a preferred implementation, the magnetic core is at least partially in contact with the susceptor.

In a preferred embodiment, the magnetic core is not exposed outside the susceptor.

In a preferred implementation, the susceptor comprises:

a substrate extending at least partially within the receiving cavity, and a receptive coating formed on the substrate.

In a preferred implementation, the induction coil is configured in the form of a helical coil extending in the axial direction of the susceptor;

the cross section of the wire material of the helical coil is configured to be flat.

In a preferred implementation, the cross-section of the wire material of the helical coil is configured such that the length extending in the axial direction of the helical coil is greater than the length extending in the radial direction.

The induction coil is configured in a spiral shape extending in the hollow axial direction.

Yet another embodiment of the present application also proposes an aerosol-generating device for heating an aerosol-generating article to generate an aerosol; the method comprises the following steps:

a receiving chamber for receiving an aerosol-generating article;

an induction coil configured to generate a varying magnetic field;

a susceptor configured to be penetrated by a varying magnetic field to generate heat to heat an aerosol-generating article received in the receiving cavity; the susceptor is configured to extend in an axial direction of the induction coil and to surround the induction coil;

a magnetic core positioned at least partially within the induction coil to prevent or reduce leakage of the varying magnetic field outside the susceptor.

Yet another embodiment of the present application also proposes a heater for an aerosol-generating device, the heater comprising:

a susceptor configured to be penetrated by a varying magnetic field to generate heat; the susceptor has a holding cavity extending in an axial direction;

a magnetic core at least partially located within the induction coil.

The above aerosol-generating device is advantageous in that the magnetic field or the magnetic lines of force are absorbed by the susceptor and the magnetic core inside and outside the induction coil, respectively, to prevent or reduce the leakage flux.

a receiving chamber for receiving an aerosol-generating article;

a heater extending at least partially within the receiving cavity for heating an aerosol-generating article; the heater includes:

a housing configured to extend at least partially in an axial direction of the receiving cavity and having a retaining cavity extending in the axial direction;

an induction coil positioned within the retention cavity of the housing and configured to generate a varying magnetic field;

a susceptor at least partially positioned within the induction coil and configured to be penetrated by a varying magnetic field to generate heat;

the housing is configured to heat the aerosol-generating article by receiving heat from the susceptor.

In a preferred implementation, the projection of the susceptor in the axial direction of the induction coil covers the hollow of the induction coil.

In a preferred implementation, the induction coil includes axially opposed first and second ends; the inductor body penetrates from the first end to the second end of the induction coil.

In a preferred implementation, the susceptor comprises an axially extending first portion of the induction coil; the extension length of the first part along the axial direction of the induction coil is greater than or equal to the extension length of the induction coil.

In a preferred implementation, the susceptor includes a second portion exposed outside of the induction coil;

In a preferred embodiment, the susceptor is at least partially in contact with the housing, thereby forming a thermal conductor with the housing.

In a preferred embodiment, the susceptor is not exposed outside the housing.

In a preferred implementation, the induction coil is configured in the form of a helical coil extending in the axial direction of the housing;

In a preferred implementation, the housing comprises ceramic.

a housing having a retention cavity extending in an axial direction;

a receiving chamber for receiving an aerosol-generating article;

a first susceptor configured to extend at least partially in an axial direction of the receiving cavity and having a retaining cavity extending in the axial direction;

an induction coil positioned within the retention cavity of the housing and configured to generate a changing magnetic field;

a second susceptor at least partially positioned within the induction coil;

the first and second susceptors are configured to be penetrated by a varying magnetic field to generate heat.

In a preferred implementation, the first susceptor, upon penetration by a varying magnetic field, generates heat and receives heat from the second susceptor, thereby heating the aerosol-generating article.

In a preferred implementation, the second susceptor is further configured to prevent or reduce leakage of the varying magnetic field outside the first susceptor.

In a preferred implementation, a projection of the second susceptor in an axial direction of the induction coil covers a hollow of the induction coil.

In a preferred implementation, the induction coil includes axially opposed first and second ends; the second inductor penetrates from the first end to the second end of the induction coil.

In a preferred embodiment, the second susceptor is at least partially in contact with the first susceptor, thereby transferring heat to the first susceptor.

In a preferred embodiment, the second receptor is not exposed to the first receptor.

In a preferred implementation, the induction coil is configured in the form of a helical coil extending in the axial direction of the first susceptor; the cross section of the wire material of the helical coil is configured to be flat.

In a preferred embodiment, the first susceptors comprise:

a substrate defining the retention cavity, and a receptive coating formed on the substrate.

a first susceptor having a holding cavity extending in an axial direction;

an induction coil positioned within the holding cavity of the first susceptor and configured to generate a changing magnetic field;

a second susceptor at least partially positioned within the induction coil and configured to be penetrated by a varying magnetic field to generate heat;

the first susceptor generates heat and receives heat from the second susceptor by being penetrated by the varying magnetic field, thereby heating the aerosol-generating article.

The above aerosol-generating device, the induction coil and the susceptor are each configured to be located within the housing of the heater, which is advantageous for miniaturization of the product.

Drawings

One or more embodiments are illustrated by way of example in the accompanying drawings, which correspond to the figures in which like reference numerals refer to similar elements and which are not to scale unless otherwise specified.

FIG. 1 is a schematic view of a conventional heating apparatus;

figure 2 is a schematic structural view of an aerosol-generating device provided by an embodiment of the present application;

FIG. 3 is an exploded view of the heater of FIG. 2, with portions not assembled;

FIG. 4 is a cross-sectional view of the heater of FIG. 2 from one perspective;

FIG. 5 is a schematic cross-sectional view of one perspective of the induction coil of FIG. 3;

FIG. 6 is a schematic structural diagram of an induction coil of yet another embodiment;

FIG. 7 is a schematic view of a heater according to still another embodiment;

FIG. 8 is an exploded view of the heater of FIG. 7, prior to assembly.

Detailed Description

In order to facilitate an understanding of the present application, the present application is described in more detail below with reference to the accompanying drawings and detailed description.

An embodiment of the present application provides an aerosol-generating device, the configuration of which can be seen in fig. 2 to 4, comprising:

a receiving chamber having an opening 50, an aerosol-generating article a, such as a cigarette, being removably received within the receiving chamber through the opening 50;

a susceptor 30, at least a portion of which extends within the receiving chamber and which heats up the aerosol-generating article a, such as a cigarette, when penetrated by the varying magnetic field to volatilize at least one component of the aerosol-generating article a to form an aerosol for smoking;

a magnetic field generator, such as an induction coil 32, for generating a varying magnetic field under an alternating current;

the battery cell 10 is a rechargeable direct current battery cell and can output direct current;

the circuit 20, which is electrically connected to the rechargeable battery cell 10 by a suitable electrical connection, converts the direct current output from the battery cell 10 into an alternating current with a suitable frequency and supplies the alternating current to the induction coil 32, so that the induction coil 32 generates a changing magnetic field.

In a more preferred implementation, the frequency of the alternating current supplied by circuit 20 to the induction coil is between 80KHz and 400KHz; more specifically, the frequency may be in the range of approximately 200KHz to 300 KHz.

In a preferred embodiment, the battery cell 10 provides a dc supply voltage in a range from about 2.5V to about 9.0V, and the battery cell 10 provides a dc current with an amperage in a range from about 2.5A to about 20A.

In a preferred embodiment, the susceptor 30 is substantially in the shape of a pin or needle, which in turn is advantageous for insertion into the aerosol-generating article a. Meanwhile, the susceptor 30 may have a length of about 12 to 19 mm, a diameter of 2.0 to 2.6 mm; these susceptors 30 may be made from grade 430 stainless steel (SS 430), and may also be made from grade 420 stainless steel (SS 420), as well as alloy materials containing iron and nickel, such as permalloy.

Further in alternative implementations, the aerosol-generating article a preferably employs a tobacco-containing material that releases volatile compounds from the substrate upon heating; or it may be a non-tobacco material that is suitable for electrically heated smoking after heating. The aerosol-generating article a preferably employs a solid substrate, and may comprise one or more of a powder, granules, shredded strips, strips or flakes of one or more of vanilla leaves, tobacco leaves, homogenised tobacco, expanded tobacco; alternatively, the solid substrate may contain additional tobacco or non-tobacco volatile flavour compounds to be released when the substrate is heated.

As further shown in fig. 2 to 4, the susceptor 30 is in the shape of a pin or needle having a holding cavity 31 therein; and the susceptor 30 is free at its front end 311 near the opening 50 and is generally configured in the shape of a conical tip for ease of insertion into the aerosol-generating article a, and the end 312 comprises an open configuration defined by the holding chamber 31 for ease of assembly of the induction coil 32 therein. In a preferred embodiment, the susceptor 30 with the holding chamber 31 has a wall thickness of about 0.15 to 0.3mm, which can be much larger than the skin depth of the susceptor 30 at which eddy currents form in the magnetic field, which is advantageous for reducing magnetic leakage and confining the magnetic field within the susceptor 30.

As another implementation, the susceptor 30 includes an elongated substrate having a holding cavity 31 and a coating of a receptive material bonded to the substrate, such as a ceramic material, a quartz lamp, the coating of a receptive material being a layer of a receptive metal or alloy material (e.g., a coating) bonded to an outer surface or an inner wall surface of the ceramic or quartz substrate, the induction coil 32 being received within the holding cavity 31 defined by the substrate. Alternatively, the ceramic matrix may provide insulation between the induction coil 32 and the inductive coating.

As further shown in fig. 2-4, an induction coil 32 for generating a magnetic field under an alternating current; in particular in the form of a spiral extending in the axial direction of the susceptor 30. In the implementation shown in fig. 3, the induction coil 32 is completely assembled and held in the holding chamber 31 of the susceptor 30, and after assembly the induction coil 32 and the susceptor 30 are thermally conductive to each other. Of course, the induction coil 32 and the susceptor 30 are insulated from each other; in an optional implementation, the induction coil 32 is insulated by an insulating layer sprayed on the surface, or by being coated with paint; or the induction coil 32 and the susceptor 30 are insulated from each other by gluing, surface oxidation, spraying an insulating layer, and the like.

As further shown in fig. 3, the induction coil 32 has between 6 and 20 windings or turns. And the induction coil 32 has an extension length of about 8-12 mm. The induction coil 32 is constructed as a solenoid having an outer diameter of about 2mm and an inner diameter of about 1.4 mm.

In practice, the inner diameter of the holding chamber 31 is substantially comparable to the outer diameter of the induction coil 32, so that the induction coil 32 is in contact or abutting contact with the inner surface of the holding chamber 31 after assembly, and thus no or very little clearance is present. In practice, the outer diameter of the induction coil 32 may be slightly less than the inner diameter of the holding chamber 31 by within 0.5mm, which facilitates assembly and control to maintain the above gap. Further, after assembly, the susceptor 30 is enabled to substantially absorb the magnetic field generated by the induction coil 32 by the susceptor 30. The magnetic field generated by the induction coil 32 is also substantially confined within the susceptor 30.

As further shown in fig. 4 and 5, the cross-sectional shape of the wire material of the induction coil 32 enclosed in the holding chamber 31 of the susceptor 30 is different from a conventional circular shape, but the cross-sectional shape is a wide or flat shape. In the cross-sectional shape shown in fig. 5, the cross-section of the wire material of the induction coil 32 has a dimension extending in the axial direction larger than a dimension extending in the radial direction, so that the induction coil 32 has a flat rectangular shape. In brief, the induction coil 32 of the above construction is completely or at least flattened in the form of wire material as compared to a conventional helical heating coil formed of a circular cross-section wire. Thus, the wire material extends to a lesser extent in the radial direction. By this measure it is advantageous that the current can be raised to enhance the magnetic field strength.

In the implementation shown in fig. 5, the cross-section of the wire material of the induction coil 32 extends approximately between 1 and 4mm in the axial direction of the helical coil; the wire material of the induction coil 32 has an extension length in the radial direction of the spiral coil of about 0.1 to 1mm.

Or in yet another alternative implementation shown in fig. 6, the wire material of the induction coil 32a is circular in cross-section.

As further shown in fig. 3, the induction coil 32 further includes:

the first and second

conductive pins

321, 322 are connected to the circuit 20, in use, via the first and second

conductive pins

321, 322, thereby providing an alternating current to the induction coil 32. The first conductive pin 321 is welded to the upper end of the induction coil 32 and then penetrates through the hollow portion 323 of the induction coil 32 to the lower end, so as to facilitate connection and assembly with the circuit 20. The second conductive pin 322 is directly connected to the lower end of the induction coil 32.

In other variant implementations, the first conductive pin 321 may also be located outside the induction coil 32 and extend from the upper end to the lower end along the axial direction of the induction coil 32; thereby facilitating connection to the circuit 20.

As an alternative implementation, the induction coil 32 and susceptor 30 may be thermally conductive to each other, and the material of the induction coil 32 is preferably made of a material having a suitable positive or negative temperature coefficient of resistance, such as a nickel-aluminum alloy, a nickel-silicon alloy, a palladium-containing alloy, a platinum-containing alloy, or the like. In use, the temperature of the susceptor 30 may be determined by sensing the resistance of the induction coil 32.

Or in yet another alternative implementation, the first conductive pin 321 and the second conductive pin 322 are made of different thermocouple wires, so that a thermocouple for detecting the temperature of the induction coil 32/susceptor 30 can be formed between them. For example, the first conductive lead 321 and the second conductive lead 322 are respectively made of two different materials selected from nickel, nickel-chromium alloy, nickel-silicon alloy, nickel-chromium-copper alloy, constantan, iron-chromium alloy Jin Dengdian.

Or in other alternative implementations, it is also possible to fill the inside of the holding cavity 31 of the susceptor 30 with a sensor for sensing the temperature of the susceptor 30, such as a conventional PTC temperature sensor, or the like, or to weld at least two thermocouple wires of different materials, for example, on the inner wall of the holding cavity 31 of the susceptor 30, and thereby form a thermocouple therebetween, which can be used to detect the temperature of the susceptor 30, it being understood that the sensor is not limited to a thermocouple.

With further reference to the preferred embodiment shown in fig. 3 and 4, the susceptor 30 also has disposed therein:

a magnetic core 33 having a substantially elongated rod-like or columnar shape; is positioned inside the induction coil 32 for preventing the magnetic field inside the induction coil 32 from leaking outside the susceptor 30.

The magnetic core 33 is made of metal or alloy containing at least one of iron, cobalt and nickel; for example, good soft or semi-hard magnetic materials, such as permalloy, stainless steel, feAl alloys, and the like. In a preferred embodiment, the magnetic core 33 is preferably made of a material having high heat capacity and thermal conductivity; for example, in the case of the same shape such as the same size, volume, etc., the magnetic core 33 is preferably made of, for example, feAl alloy, and the content (mass percentage) of Al in FeAl alloy can be further increased from the conventional 6% to 8 to 20%, preferably 10 to 12%; since the thermal conductivity and specific heat capacity of Al are both higher than those of Fe, higher thermal conversion efficiency can be provided.

In a more preferred embodiment, the core 33 is required to fill the coil as much as possible, and as shown in fig. 4, the core 33 extends from the lower end of the induction coil 32 to the upper end of the induction coil 32; in an implementation, the extension of the magnetic core 33 in the axial direction of the induction coil 32 is greater than or equal to the axial extension of the induction coil 32. Further in the preferred embodiment shown in fig. 4, the magnetic core 33 is at least partially convex with respect to the induction coil 32 after penetrating the induction coil 32.

With further reference to the preferred implementation shown in fig. 3 and 4, the configuration of the magnetic core 33 includes:

an elongated rod-shaped first portion 331 which penetrates from the lower end to the upper end of the induction coil 32 in assembly by the first portion 331;

a second portion 332, the second portion 332 having an outer diameter or a cross-sectional area larger than the first portion 331 and/or the hollow 323 of the induction coil 32, thereby forming a step 333 at a portion combined with the first portion 331; when assembled, the lower end of the induction coil 32 abuts the step 333, and the stop is provided by the second portion 332.

In a preferred implementation, the elongated first portion 331 has an extension of about 10-15 mm; the elongated first portion 331 has an outer diameter of less than about 1.5 mm.

According to the figure, the second portions 332 are in contact with the inner walls of the holding chamber 31 of the susceptor 30, and are thus thermally conductive with respect to each other. Further, the use of the magnetic core 33 to at least partially provide a buffer for temperature variations in the susceptor 30 is advantageous in preventing a sudden temperature drop in the susceptor 30 due to the airflow passing over the surface of the susceptor 30 during the pumping process, maintaining the temperature of the susceptor 30 within a suitable range, and ultimately, providing a uniform aerosol generation or taste during the pumping process.

Further in a preferred implementation shown in fig. 3 or 4, the apparatus further comprises:

a base or flange 34; in the figure the base or flange 34 is PEEK, a ceramic such as ZrO ₂ And Al ₂ O ₃ Heat-resistant materials such as ceramics. In preparation, the base or flange 34 is bonded by high temperature glue, molded, e.g., in-mold, orWelded or the like to the lower end of the susceptor 30 and held in fixed connection; the aerosol-generating device may then be supported, clamped or held by the base or flange 34 to stably mount and hold the susceptor 30.

Further in accordance with the preferred embodiment shown in fig. 3 and 4, the base or flange 34 is annular in shape and has a central bore 341; when the base or flange 34 is assembled with the lower end of the susceptor 30, the first conductive leads 321 and the second conductive leads 322 extend through the central opening 341 of the base or flange 34 to facilitate connection to the circuit 20.

Also according to the preferred embodiment shown in fig. 4, the inner diameter of the central hole 341 of the base or flange 34 is smaller than the outer diameter of the second portion 332 of the magnetic core 33, which is advantageous for fixing and retaining the magnetic core 33 in the susceptor 30 by supporting it.

Further figure 8 shows a further preferred implementation comprising:

a susceptor 30b in the form of a pin or needle, a holding chamber 31b in the susceptor 30b for accommodating and enclosing an induction coil 32b;

a magnetic core 33b including a first portion 331b in an elongated rod shape, and a second portion 332b; a step 333b is formed at a portion where the second portion 332b is combined with the first portion 331 b;

the first portion 331b of the magnetic core 33b penetrates from the upper end of the induction coil 32b to the lower end of the induction coil 32b in the assembly; the core 33b is stopped by the step 333b against the upper end of the induction coil 32 b. Meanwhile, the first conductive pin 321b and the second conductive pin 322b of the induction coil 32b penetrate through the central hole 341b of the base or flange 34b to the outside of the susceptor 30b, and are connected to the convenience circuit 20.

In this embodiment, the second portion 332b is generally conical and is thermally conductive to each other by the mating fit, securing, or contact, of the conical second portion 332b with the conical tip of the holding cavity 31b of the susceptor 30 b.

Of course, in this embodiment, the first portion 331b of the magnetic core 33b extends along the axial direction of the induction coil 32b by a length greater than or equal to the axial direction extension of the induction coil 32 b.

In yet another embodiment of the present application, the upper susceptor 30/30b, the induction coil 32/32b and the magnetic core 33/33b are insulated from each other. In a preferred embodiment, they are insulated by a filled high temperature resistant insulating glue, such as an epoxy glue; specifically, in the assembling process, after the surfaces of the induction coil 32/32b and the magnetic core 33/33b are dipped/brushed with high-temperature resistant insulating glue, the induction coil 32/32b and the magnetic core 33/33b are assembled into the sensor 30/30b, and then the high-temperature resistant insulating glue is cured by heating. In an alternative embodiment, the refractory insulating paste is cured by blowing hot air through a hot air gun directed at the holding chamber 31/31b of the susceptor 30/30 b. Or in yet another alternative embodiment, the refractory glue is cured by energizing the induction coil 32/32b to heat it, for example by initially heating it for a period of time at a relatively low power and then gradually increasing to about 4W until the refractory glue inside the susceptor 30/30b is fully cured.

Or in yet another alternative implementation, the susceptor 30/30b, the induction coil 32/32b and the magnetic core 33/33b are insulated by filled glaze powder; or by forming a glaze coating on the surfaces of the induction coil 32/32b and the magnetic core 33/33 b.

It is advantageous to prevent or reduce magnetic leakage by absorbing the magnetic field or lines of force generated by the induction coil 32/32b inside and outside the induction coil 32/32b through the susceptor 30/30b and the magnetic core 33/33b, respectively.

Meanwhile, the induction coil 32/32b with the above magnetic core 33/33b inside is equivalent to an inductor with an iron core inside, which is beneficial to increase the inductance value of the induction coil 32/32b after being coupled to the circuit 20.

a heater 30, at least a portion of which extends within the receiving chamber and which generates heat when penetrated by a varying magnetic field, thereby to heat an aerosol-generating article a, such as a cigarette, to volatilise at least one component of the aerosol-generating article a to form an aerosol for smoking;

In a preferred embodiment, the battery cell 10 provides a dc supply voltage in a range from about 2.5V to about 9.0V, and the battery cell 10 may provide a dc current with an amperage in a range from about 2.5A to about 20A.

In a preferred embodiment, the heater 30 is generally in the shape of a pin or needle, which in turn is advantageous for insertion into the aerosol-generating article a. Meanwhile, the heater 30 may have a length of about 12 to 19 mm, a diameter of 2.0 to 4.0 mm; these heaters 30 may be comprised of grade 430 stainless steel (SS 430), may also be comprised of grade 420 stainless steel (SS 420), and may be comprised of an alloy material containing iron and nickel, such as permalloy.

As further shown in fig. 2-4, heater 30 is configured in the shape of a pin, needle; in this implementation, the heater 30 includes:

a housing 31 defining the outer configuration of the heater 30; in implementation, the housing 31 is configured in the shape of a pin or needle having a holding cavity 310 therein; and the front end 311 of the housing 31 adjacent the opening 50 is free and is generally configured in the shape of a tapered tip for ease of insertion into the aerosol-generating article a, and the end 312 includes an open configuration defined by the holding chamber 310 for ease of assembly of the induction coil 32 therein. In a preferred implementation, the wall thickness of the housing 31 with the holding chamber 310 is approximately 0.15 to 0.3mm. In this implementation, the housing 31 heats the aerosol-generating article a by receiving and transferring heat from the susceptor 33 inside.

In some embodiments, the housing 31 is made of ceramic material (e.g., alumina, zirconia), quartz, aluminum, copper, etc. with excellent thermal conductivity and/or radiation characteristics. For example, in some preferred implementations, the housing 31 is made of a non-metallic inorganic material, such as a metal oxide (e.g., mgO, al) ₂ O ₃ 、 B ₂ O ₃ Etc.), metal nitrides (Si) ₃ N ₄ 、B ₃ N ₄ 、Al ₃ N ₄ Etc.) or other high thermal conductivity composite ceramic materials.

As further shown in fig. 3 and 4, the heater 30 further comprises:

an induction coil 32 for generating a magnetic field under an alternating current. Specifically, in configuration, the induction coil 32 is in the shape of a spiral extending in the axial direction of the heater 30. In the implementation shown in fig. 3, the induction coil 32 is completely assembled and held within the holding cavity 310 of the housing 31, and the induction coil 32 and the housing 31 are thermally conductive to each other after assembly. Of course, the induction coil 32 and the housing 31 are insulated from each other; when the housing 31 comprises a metal material, the induction coil 32 is insulated by an insulating layer sprayed on the surface or by a mode of painting; alternatively, the surfaces of the induction coil 32 and the metal case 31 that are in contact with each other are insulated by applying glue, oxidizing the surfaces, spraying an insulating layer, or the like.

As further shown in fig. 3, the induction coil 32 has between 6 and 20 windings or turns. And, the induction coil 32 has an extension length of about 8-12 mm. The induction coil 32 is constructed as a solenoid having an outer diameter of about 2mm and an inner diameter of about 1.4 mm.

In practice, the inner diameter of the holding chamber 310 is substantially comparable to the outer diameter of the induction coil 32, such that the induction coil 32 contacts or abuts the inner surface of the holding chamber 310 after assembly, with no or minimal clearance. In practice, the outer diameter of the induction coil 32 may be slightly smaller than the inner diameter of the holding chamber 310 by within 0.5mm, which facilitates assembly and controlled maintenance of the above gap. In further preferred embodiments, the housing 31 comprises a metal material, thereby allowing the susceptor 30 to substantially confine the magnetic field generated by the induction coil 32 within the heater 30 after assembly.

As further shown in fig. 4 and 5, the cross-sectional shape of the wire material of the induction coil 32 enclosed in the holding cavity 310 of the housing 31 is different from a conventional circular shape, but the cross-sectional shape is a wide or flat shape. In the cross-sectional shape shown in fig. 5, the cross-section of the wire material of the induction coil 32 has a dimension extending in the axial direction larger than a dimension extending in the radial direction, so that the induction coil 32 has a flat rectangular shape. In brief, the induction coil 32 of the above construction is completely or at least flattened in the form of wire material as compared to a conventional helical heating coil formed of a circular cross-section wire. Thus, the wire material extends to a lesser extent in the radial direction. By this measure, it is advantageous that the current can be raised to enhance the magnetic field strength.

Or in yet another variant implementation shown in fig. 6, the wire material of the induction coil 32a is circular in cross-section.

As further shown in fig. 3, the induction coil 32 further includes:

the first and second

conductive pins

321, 322 are connected to the circuit 20, in use, via the first and second

conductive pins

With further reference to the preferred embodiment shown in fig. 3 and 4, the heater 30 further includes:

a susceptor 33 mainly serving as a part for generating heat from the heater 30; the susceptor 33, which is substantially in the form of an elongated rod or column, is positioned inside the induction coil 32 and can be penetrated by a changing magnetic field to generate heat.

In some preferred implementations, the material of the susceptor 33 is a sensitive metal or alloy containing at least one of iron, cobalt, and nickel; such as good soft or semi-hard magnetic materials, e.g. permalloy, stainless steel, feAl alloys, etc.

In a preferred embodiment, the outer diameter of the susceptor 33 is substantially the same as or close to the inner diameter of the induction coil 32, thereby substantially filling the inner space of the induction coil 32; it is advantageous to prevent the magnetic field inside the induction coil 32 from leaking outward.

In a more preferred embodiment, the susceptor 33 is required to fill the coil as much as possible, and as shown in fig. 4, the susceptor 33 penetrates from the lower end of the induction coil 32 to the upper end of the induction coil 32; in practice, the extension of the susceptor 33 in the axial direction of the induction coil 32 is greater than or equal to the axial extension of the induction coil 32. Further in the preferred embodiment shown in fig. 4, the susceptor 33 is at least partially raised relative to the induction coil 32 after penetrating the induction coil 32.

With further reference to the preferred embodiment shown in fig. 3 and 4, the configuration of susceptor 33 includes:

According to the illustration, the second portions 332 are in contact with the inner walls of the holding cavity 310 of the housing 31 and are thus thermally conductive to each other. Further, the heat generated by the susceptor 33 is directly transferred to the housing 31 by contacting the housing 31.

In some other variations, the susceptor 33 may be in indirect thermal communication with the housing 31 via the induction coil 32. That is, the induction coil 32 is thermally conductive with both the housing 31 and the susceptor 33.

In some preferred implementations, the induction coil 32 is made of a material with high thermal conductivity and low resistivity, such as gold, silver, copper, etc.; there is more heat transfer efficiency while having a relatively low electrical resistance.

In still other variations, the material of the induction coil 32 is preferably made of a material with a suitable positive or negative temperature coefficient of resistance, such as a nickel-aluminum alloy, a nickel-silicon alloy, a palladium-containing alloy, a platinum-containing alloy, etc. In use, the temperature of the heater 30 can be determined by sensing the resistance of the induction coil 32.

Or in yet another alternative implementation, the first conductive pin 321 and the second conductive pin 322 are made of different thermocouple wires, so that a thermocouple for detecting the temperature of the induction coil 32/the heater 30 can be formed between them. For example, the first conductive lead 321 and the second conductive lead 322 are respectively made of two different materials selected from nickel, nickel-chromium alloy, nickel-silicon alloy, nickel-chromium-copper alloy, constantan, iron-chromium alloy Jin Dengdian.

Or in other alternative implementations, it is also possible to fill the inside of the holding cavity 310 of the housing 31 with a sensor for sensing the temperature of the heater 30, such as a conventional PTC temperature sensor, or the like, or weld at least two electric thermocouple wires of different materials on the inner wall of the holding cavity 310 of the housing 31, for example, to form a thermocouple therebetween, which can be used for detecting the temperature of the heater 30, and it is understood that the sensor is not limited to the thermocouple.

In further preferred embodiments, the gap interface between the induction coil 32 and the inductor 33 in the holding cavity 310 of the housing 31 is preferably bonded or encapsulated by a high thermal conductivity material, which may be selected from high thermal conductivity metals or insulating materials, such as aluminum, carbon-based (graphite, diamond), boron nitride, etc., and is advantageous for increasing the heat capacity of the heater 30.

a base or flange 34; in the figure the base or flange 34 is PEEK, a ceramic such as ZrO ₂ And Al ₂ O ₃ Heat-resistant materials such as ceramics. In preparation, the base or flange 34 is fixed to the lower end of the housing 31 by high temperature adhesive bonding, molding such as in-mold injection, or welding, and remains fixedly connected; further, the aerosol-generating device may be supported, clamped, held, or the like to stably mount and hold the heater 30 to the base or flange 34.

Further in accordance with the preferred embodiment shown in fig. 3 and 4, the base or flange 34 is annular in shape and has a central bore 341; when the base or flange 34 is assembled with the lower end of the heater 30, the first conductive pin 321 and the second conductive pin 322 penetrate through the central hole 341 of the base or flange 34, thereby facilitating connection with the circuit 20.

Also in accordance with the preferred embodiment shown in fig. 4, the inner diameter of the central bore 341 of the base or flange 34 is smaller than the outer diameter of the second portion 332 of the susceptor 33, which is advantageous for securing and retaining the susceptor 33 within the housing 31 by supporting it.

Further figure 8 shows a further preferred implementation comprising:

a pin or needle-like housing 31b, a holding cavity 310b in the housing 31b for receiving and enclosing the induction coil 32b;

a susceptor 33b including a first portion 331b having an elongated rod shape, and a second portion 332b; a step 333b is formed at a portion where the second portion 332b is combined with the first portion 331 b.

The induction coil 32b is used for generating a changing magnetic field;

the susceptor 33b is penetrated by a changing magnetic field to generate heat;

the housing 31b heats the aerosol-generating article a by receiving heat from the susceptor 33b.

The first portion 331b of the inductor 33b penetrates from the upper end of the induction coil 32b to the lower end of the induction coil 32b in the assembly; the susceptor 33b forms a stop against the upper end of the induction coil 32b by a step 333b. Meanwhile, the first conductive pin 321b and the second conductive pin 322b of the induction coil 32b penetrate through the central hole 341b of the base or flange 34b to the outside of the housing 31b, and are connected to the convenience circuit 20.

In this embodiment, the second portion 332b of the susceptor 33b is generally tapered and is configured to be thermally conductive to each other by the tapered second portion 332b being cooperatively fitted into, or in contact with, the tapered top end of the holding cavity 310b of the housing 31 b.

Of course, in this embodiment, the first portion 331b of the susceptor 33b extends in the axial direction of the induction coil 32b by a length greater than or equal to the axial extension of the induction coil 32 b.

In yet another embodiment of the present application, the above housing 31/31b, the induction coil 32/32b and the induction body 33/33b are insulated from each other. In a preferred embodiment, they are insulated by a filled high temperature resistant insulating glue, such as an epoxy glue; specifically, in the assembling process, after the surfaces of the induction coil 32/32b and the sensor 33/33b are dipped/brushed with high-temperature-resistant insulating glue, the induction coil 32/32b and the sensor 33/33b are assembled into the shell 31/31b, and then the high-temperature-resistant insulating glue is cured by heating. In an alternative embodiment, the refractory insulating paste is cured by hot air blowing through a heat gun directed at the holding cavity 310/310b of the housing 31/31 b. Or in yet another alternative implementation, the high temperature resistant adhesive is cured by energizing the induction coil 32/32b to generate heat, for example, by initially heating at a relatively low power for a period of time and then gradually increasing to about 4W until the high temperature resistant adhesive inside the housing 31/31b is fully cured.

Or in yet another alternative implementation, the shell 31/31b, the induction coil 32/32b and the susceptor 33/33b are insulated by filled glaze powder; or by forming a glaze coating on the surfaces of the induction coil 32/32b and the susceptor 33/33 b.

The above is advantageous for preventing or reducing magnetic leakage by absorbing the magnetic field or magnetic lines generated by the induction coil 32/32b inside and outside the induction coil 32/32b through the housing 31/31b and the susceptor 33/33b, respectively.

Meanwhile, the induction coil 32/32b with the inductor 33/33b inside is equivalent to an inductor with an iron core inside, which is beneficial to increasing the inductance value of the induction coil 32/32b after being coupled to the circuit 20.

In a more preferred implementation, the frequency of the alternating current supplied by the circuit 20 to the induction coil is between 80KHz and 400KHz; more specifically, the frequency may be in the range of approximately 200KHz to 300 KHz.

Further in alternative implementations, the aerosol-generating article a preferably employs a tobacco-containing material that releases volatile compounds from the substrate upon heating; or it may be a non-tobacco material that is suitable for electrically heated smoking after heating. The aerosol-generating article a preferably employs a solid substrate, and may comprise one or more of a powder, granules, shredded strips, strips or flakes of one or more of vanilla leaves, tobacco leaves, homogenised tobacco, expanded tobacco; alternatively, the solid substrate may contain additional tobacco or non-tobacco volatile flavour compounds to be released upon heating of the substrate.

a first susceptor 31 defining the outer configuration of the heater 30 and capable of being penetrated by a varying magnetic field to generate heat; in practice, the first susceptor 31 is configured in the shape of a pin or needle having a holding cavity 310 therein; and the front end 311 of the first susceptor 31 adjacent the opening 50 is free and is generally configured in the shape of a tapered tip for ease of insertion into the aerosol-generating article a, and the end 312 includes an open configuration defined by the holding cavity 310 for ease of assembly of the induction coil 32 therein. In a preferred embodiment, the wall thickness of the housing 31 with the holding chamber 310 is approximately 0.15 to 0.3mm.

As further shown in fig. 3 and 4, the heater 30 further comprises:

an induction coil 32 for generating a magnetic field under an alternating current. Specifically in configuration, the induction coil 32 is in the shape of a spiral extending in the axial direction of the heater 30. In the implementation shown in fig. 3, the induction coil 32 is completely assembled and held within the holding cavity 310 of the first susceptor 31, and the induction coil 32 and the first susceptor 31 are thermally conductive to each other after assembly. Of course, the induction coil 32 and the first susceptor 31 are insulated from each other; when the first sensing body 311 comprises a metal material, the induction coil 32 is insulated by an insulating layer sprayed on the surface or by being coated with paint; or the induction coil 32 and the first susceptor 31 made of metal are insulated from each other by applying glue, surface oxidation, spraying an insulating layer, or the like.

the second susceptor 33, which is substantially in the form of an elongated rod or column, is positioned inside the induction coil 32 and can be penetrated by a varying magnetic field to generate heat.

In this embodiment, the first susceptor 31 and the second susceptor 33 can generate heat by being inside and outside the induction coil 32; further, in use, the heater 30 is enabled to retain heat by the second susceptor 33 within the hollow interior of the induction coil 32; which in turn helps to maintain the thermal capacity of the heater 30, is advantageous in preventing the temperature of the heater 30 from jumping as the airstream flows across the surface of the heater 30 during draw.

In this embodiment, the first and second susceptors 31 and 33 are each made of a sensitive material; such as good soft or semi-hard magnetic materials, e.g. permalloy, stainless steel, feAl alloys, etc.

In this embodiment, the first susceptor 31 heats the aerosol-generating product a directly by its own induction heating, and on the other hand, receives the heat transferred from the second susceptor 33 and heats the aerosol-generating product a.

Similarly, in some embodiments, the outer diameter of the second susceptor 33 is substantially the same as or close to the inner diameter of the induction coil 32, thereby substantially filling the inner space of the induction coil 32; it is advantageous to prevent the magnetic field inside the induction coil 32 from leaking outward.

In a more preferred embodiment, the second susceptor 33 is required to fill the inside of the coil as much as possible, and as shown in fig. 4, the second susceptor 33 penetrates from the lower end of the induction coil 32 to the upper end of the induction coil 32; in practice, the second susceptor 33 has an extension in the axial direction of the induction coil 32 that is greater than or equal to the axial extension of the induction coil 32. Further in the preferred embodiment shown in fig. 4, the second susceptor 33 is at least partially convex with respect to the induction coil 32 after penetrating the induction coil 32.

With further reference to the preferred embodiment shown in fig. 3 and 4, the second susceptor 33 is constructed by:

According to the illustration, the second portion 332 is in contact with the inner wall of the holding chamber 310 of the first susceptor 31 and is thus thermally conductive to each other. Further, the heat generated by the second susceptor 33 during heat generation can be directly transferred to the first susceptor 31 by contacting the first susceptor 31.

In some other variations, the second susceptor 33 may be in indirect thermal communication with the first susceptor 31 via the induction coil 32. That is, the induction coil 32 is thermally conductive to both the first susceptor 31 and the second susceptor 33.

Or in yet another alternative implementation, the first conductive pin 321 and the second conductive pin 322 are made of different thermocouple wires, so that a thermocouple for detecting the temperature of the induction coil 32/the heater 30 can be formed between them. For example, the first conductive lead 321 and the second conductive lead 322 are respectively made of two different materials selected from nickel, nickel-chromium alloy, nickel-silicon alloy, nickel-chromium-copper alloy, constantan, iron-chromium alloy Jin Dengdian alloy.

Or in other alternative implementations, it is also possible to fill a sensor for sensing the temperature of the heater 30, such as a conventional PTC temperature sensor, inside the holding cavity 310 of the first sensor body 31, or weld at least two electric thermocouple wires of different materials on the inner wall of the holding cavity 310 of the first sensor body 31, for example, and form a thermocouple therebetween for detecting the temperature of the heater 30, and it is understood that the sensor is not limited to a thermocouple.

Further in the preferred implementation shown in fig. 3 or 4, the apparatus further comprises:

a base or flange 34; in the figure the base or flange 34 is PEEK, a ceramic such as ZrO ₂ And Al ₂ O ₃ Heat-resistant materials such as ceramics. In preparation, the base or flange 34 is fixed to the lower end of the first sensor 31 by high temperature adhesive bonding, molding such as in-mold injection molding, or welding; the aerosol-generating device may be supported, held, or held byThe base or flange 34 provides a stable mounting and retention for the heater 30.

Also in accordance with the preferred embodiment shown in FIG. 4, the inner diameter of the central bore 341 of the base or flange 34 is smaller than the outer diameter of the second portion 332 of the second susceptor 33, which is advantageous for securing and retaining the second susceptor 33 within the first susceptor 31 by supporting it.

Further figure 8 shows a further preferred implementation comprising:

a first susceptor 31b in the form of a pin or needle, a holding cavity 310b in the first susceptor 31b for receiving and enclosing the induction coil 32b;

a second susceptor 33b including a first portion 331b having an elongated rod shape and a second portion 332b; a step 333b is formed at a portion where the second portion 332b is combined with the first portion 331 b.

The induction coil 32b is used for generating a changing magnetic field; the first susceptor 31b and the second susceptor 33b are penetrated by a changing magnetic field to generate heat; the first susceptor 31b portion may be capable of directly inducing heat to heat the aerosol-generating article a and the other portion may also be capable of in turn heating the aerosol-generating article a by receiving heat from the second susceptor 33b.

The first portion 331b of the second susceptor 33b penetrates from the upper end of the induction coil 32b to the lower end of the induction coil 32b in assembly; the second susceptor 33b is stopped by abutment of the step 333b against the upper end of the induction coil 32 b. Meanwhile, the first conductive pin 321b and the second conductive pin 322b of the induction coil 32b penetrate through the central hole 341b of the base or flange 34b to the outside of the first inductor 31b, so as to be connected to the convenience circuit 20.

In this embodiment, the second portion 332b of the second sensor 33b is generally tapered and is configured to be thermally conductive to each other by the tapered second portion 332b engaging and securing, or contacting, the tapered top end of the holding cavity 310b of the first sensor 31 b.

Of course, in this embodiment, the first portion 331b of the second susceptor 33b extends in the axial direction of the induction coil 32b by a length greater than or equal to the axial extension of the induction coil 32 b.

In yet another embodiment of the present application, the first susceptor 31/31b, the induction coil 32/32b and the second susceptor 33/33b are insulated from each other. In a preferred embodiment, they are insulated by a filled high temperature resistant insulating glue, such as an epoxy glue; in the assembling process, after the surfaces of the induction coil 32/32b and the second inductor 33/33b are dipped/brushed with high-temperature resistant insulating glue, the induction coil 32/32b and the second inductor 33/33b are assembled into the first inductor 31/31b, and then the high-temperature resistant insulating glue is cured by heating. In an alternative embodiment, the refractory insulating paste is cured by heating by blowing hot air through a heat gun directed at the holding cavity 310/310b of the first susceptor 31/31 b. Or in yet another alternative, the high temperature resistant adhesive is cured by energizing the induction coil 32/32b to generate heat, for example, by initially heating at a relatively low power for a period of time and then gradually increasing to about 4W until the high temperature resistant adhesive inside the first susceptor 31/31b is fully cured.

In general, in practice, the first susceptors 31/31b may be made from a single receptive material. As still another modified example, the above first susceptor 31/31b is prepared by an elongated substrate having the holding chamber 310 and a coating layer of a susceptor material bonded to the substrate, for example, the substrate includes a ceramic material, a quartz lamp, and the coating layer of a susceptor material is a layer (for example, a coating layer) of a susceptor metal or alloy material bonded to the outer surface or the inner wall surface of the ceramic substrate or the quartz substrate. In this alternative implementation, the ceramic matrix may provide insulation between the first susceptor 31/31b and the induction coil 32/32 b.

It should be noted that the description and drawings of the present application illustrate preferred embodiments of the present application, but the present application is not limited to the embodiments described in the present application, and furthermore, those skilled in the art can make modifications or changes according to the above description, and all such modifications and changes should fall within the scope of the appended claims of the present application.

Claims

1. An aerosol-generating device for heating an aerosol-generating article to generate an aerosol; it is characterized by comprising:

a receiving chamber for receiving an aerosol-generating article;

an induction coil located within the holding cavity of the susceptor and configured to generate a varying magnetic field;

a magnetic core located at least partially within the induction coil.

2. An aerosol-generating device according to claim 1, wherein the magnetic core comprises at least any one of iron, cobalt or nickel.

3. An aerosol-generating device according to claim 1, wherein the magnetic core comprises an iron-aluminum alloy.

4. An aerosol-generating device according to claim 3, wherein the iron-aluminium alloy comprises 8 to 20% by mass of aluminium.

5. Aerosol-generating device according to any one of claims 1 to 4, wherein a projection of the magnetic core in the axial direction of the induction coil covers the hollow of the induction coil.

6. An aerosol-generating device according to any one of claims 1 to 4, wherein the induction coil comprises axially opposed first and second ends; the magnetic core penetrates from the first end to the second end of the induction coil.

7. An aerosol-generating device according to any one of claims 1 to 4, wherein the magnetic core comprises a first portion extending axially of the induction coil; the extension length of the first part along the axial direction of the induction coil is greater than or equal to the extension length of the induction coil.

8. An aerosol-generating device according to claim 7, wherein the first portion is substantially elongate in the shape of a rod.

9. An aerosol-generating device according to any one of claims 1 to 4, wherein the magnetic core comprises a second portion exposed outside the inductive coil;

the cross-sectional area of the hollow of the induction coil is equal to or less than the cross-sectional area of the second portion.

10. An aerosol-generating device according to claim 9, wherein the second portion is arranged to abut one of the ends of the induction coil in the axial direction.

11. Aerosol-generating device according to any one of claims 1 to 4, wherein the magnetic core is at least partially in contact with the susceptor.

12. Aerosol-generating device according to any one of claims 1 to 4, wherein the core is not exposed outside the susceptor.

13. Aerosol-generating device according to any one of claims 1 to 4, wherein the susceptor comprises:

14. Aerosol-generating device according to any one of claims 1 to 4, wherein the induction coil is configured in the form of a helical coil extending in the axial direction of the susceptor;

15. The aerosol-generating device of claim 14, wherein a cross-section of the wire material of the helical coil is configured to extend a greater length in an axial direction than in a radial direction of the helical coil.

16. An aerosol-generating device for heating an aerosol-generating article to generate an aerosol; it is characterized by comprising:

a receiving cavity for receiving an aerosol-generating article;

an induction coil configured to generate a varying magnetic field;

a magnetic core located at least partially within the induction coil to prevent or reduce leakage of the varying magnetic field outside the susceptor.

17. A heater for an aerosol-generating device, the heater comprising:

a magnetic core at least partially located within the induction coil.

18. An aerosol-generating device for heating an aerosol-generating article to generate an aerosol; it is characterized by comprising:

a receiving cavity for receiving an aerosol-generating article;

the housing is configured to in turn heat the aerosol-generating article by receiving heat from the susceptor.

19. Aerosol-generating device according to claim 18, wherein a projection of the susceptor in an axial direction of the induction coil covers a hollow of the induction coil.

20. Aerosol-generating device according to claim 18 or 19, wherein the induction coil comprises axially opposed first and second ends; the inductor body penetrates from the first end to the second end of the induction coil.

21. Aerosol-generating device according to claim 18 or 19, wherein the susceptor comprises a first portion extending in an axial direction of the induction coil; the extension length of the first part along the axial direction of the induction coil is greater than or equal to the extension length of the induction coil.

22. An aerosol-generating device according to claim 21, wherein the first portion is substantially in the form of an elongate rod.

23. Aerosol-generating device according to claim 18 or 19, wherein the susceptor comprises a second portion exposed outside the induction coil;

24. An aerosol-generating device according to claim 23, wherein the second portion is arranged to abut one of the ends of the induction coil in the axial direction.

25. An aerosol-generating device according to claim 18 or 19, wherein the susceptor is at least partially in contact with the housing, thereby forming a thermal conductor with the housing.

26. An aerosol-generating device according to claim 18 or 19, wherein the susceptor is not exposed outside the housing.

27. Aerosol-generating device according to claim 18 or 19, wherein the induction coil is configured in the form of a helical coil extending in an axial direction of the housing;

the cross section of the wire material of the spiral coil is configured to be flat.

28. The aerosol-generating device of claim 27, wherein a cross-section of the wire material of the helical coil is configured to extend a greater length in an axial direction than in a radial direction of the helical coil.

29. An aerosol-generating device according to claim 18 or 19, wherein the housing comprises ceramic.

30. A heater for an aerosol-generating device, the heater comprising:

a housing having a retention cavity extending in an axial direction;

the housing is configured to, in turn, heat an aerosol-generating article by receiving heat from the susceptor.

31. An aerosol-generating device for heating an aerosol-generating article to generate an aerosol; it is characterized by comprising:

a receiving chamber for receiving an aerosol-generating article;

a first susceptor configured to extend at least partially in an axial direction of the receiving cavity and having a retention cavity extending in the axial direction;

a second susceptor at least partially positioned within the induction coil;

the first susceptor and the second susceptor are configured to be penetrated by a varying magnetic field to generate heat.

32. The aerosol-generating device of claim 31, wherein the first susceptor generates heat and receives heat from the second susceptor by being penetrated by the varying magnetic field, thereby heating the aerosol-generating article.

33. The aerosol-generating device of claim 31, wherein the second susceptor is further configured to prevent or reduce leakage of the varying magnetic field outside the first susceptor.

34. Aerosol-generating device according to any one of claims 31 to 33, wherein a projection of the second susceptor in the axial direction of the induction coil covers the hollow of the induction coil.

35. An aerosol-generating device according to any one of claims 31 to 33, wherein the inductive coil comprises axially opposed first and second ends; the second inductor penetrates from the first end to the second end of the induction coil.

36. An aerosol-generating device according to any one of claims 31 to 33, wherein the susceptor comprises a first portion extending axially of the induction coil; the extension length of the first part along the axial direction of the induction coil is larger than or equal to the extension length of the induction coil.

37. An aerosol-generating device according to any one of claims 31 to 33, wherein the susceptor comprises a second portion exposed outside the induction coil;

38. The aerosol-generating device of claim 37, wherein the second portion is arranged to abut one of the ends of the inductive coil in the axial direction.

39. The aerosol generating device of any of claims 31 to 33, wherein the second susceptor is at least partially in contact with the first susceptor to transfer heat to the first susceptor.

40. An aerosol-generating device according to any one of claims 31 to 33, wherein the second susceptor is not exposed to the first susceptor.

41. Aerosol-generating device according to any one of claims 31 to 33, wherein the inductive coil is configured in the form of a helical coil extending in an axial direction of the first susceptor; the cross section of the wire material of the helical coil is configured to be flat.

42. An aerosol-generating device according to any one of claims 31 to 33, wherein the first susceptor comprises:

43. A heater for an aerosol-generating device, the heater comprising:

a first susceptor having a holding cavity extending in an axial direction;

the first susceptor, upon penetration by a varying magnetic field, generates heat and receives heat from the second susceptor, thereby heating the aerosol-generating article.