HEATING ASSEMBLY, ATOMIZING CORE AND AEROSOL GENERATING DEVICE

Abstract

A heating assembly is provided. The heating assembly includes: a substrate; at least one heat generating element, the heat generating element being formed on the substrate; at least two electrical contacts, the electrical contacts being formed on the substrate, and the electric contacts being electrically connected to the heat generating element; and at least one heat insulation structure, the heat insulation structure being formed on the substrate and located between the heat generating element and the electrical contacts. The present invention further relates to an atomizing core and an aerosol generating device. The heating assembly, the atomizing core, and the aerosol generating device provided can limit heat loss of a hot area and avoid the extremely high temperature of a cold area, thereby improving the atomization efficiency and reducing heat resistance requirements of the heating assembly, the atomizing core, and the aerosol generating device for the electric contacts.

Description

TECHNICAL FIELD

The present disclosure relates to the technical field of aerosol generating devices, in particular to a heating assembly, an atomizing core and an aerosol generating device.

BACKGROUND

The aerosol generating device is mainly composed of two parts: an atomizing assembly and a battery assembly. The atomizing assembly generally includes an atomizing core and a liquid storage chamber. The liquid storage chamber stores the e-liquid, and the atomizing core absorbs the e-liquid from the liquid storage chamber for atomizing to form smoke. The liquid guiding member and the heating assembly in the atomizing core are the core components of the atomizing technology, which play a decisive role in the taste of the aerosol generating device. The heating assembly is configured for heating the e-liquid transported from the liquid guiding member to the heating assembly, so as to atomize the e-liquid to generate smoke. However, the heat distribution in different areas of the heating assembly commonly used in the prior art cannot be regulated, and the heat loss is serious, thereby seriously reducing the atomizing efficiency. In addition, in the prior art, the edge area of the heating assembly is provided with electrical contacts for connecting to an external power source; because the temperature of the edge area of the heating assembly in the prior art is also very high, the heating assembly in the prior art has to meet high requirements of heat resistance for the electrical contacts.

SUMMARY

In view of above, the present disclosure provides, in a first aspect, a heating assembly capable of limiting heat loss, improving atomizing efficiency and having low heat resistance requirements for the electrical contacts.

A heating assembly for being used in an aerosol generating device includes:

a substrate;

at least one heat generating element, wherein the heat generating element is formed on the substrate;

at least two electrical contacts, wherein the electrical contacts are formed on the substrate, the electrical contacts are electrically connected to the heat generating element;

at least one heat insulation structure, wherein the heat insulation structure is formed on the substrate and located between the heat generating element and the electrical contacts.

In one embodiment, the heat generating element is arranged at the center of the substrate, and the electrical contacts are arranged at the ends of the substrate.

In one embodiment, the heat insulation structure is located on one side of the heat generating element, and the at least two electrical contacts are located at one end of the substrate away from the heat generating element.

In one embodiment, the heat insulation structure is air cavity.

In one embodiment, the air cavity penetrates through the substrate along a thickness direction of the substrate.

In one embodiment, a group of air cavities are respectively formed on both sides of each heat generating element, and a side of each group of air cavities away from the heat generating element is formed with one of the electrical contacts.

In one embodiment, the heating assembly is divided into a cold area, a hot area and a transition area, the heat generating element is arranged in the hot area, and the electrical contacts are arranged in the cold area, the heat insulation structure is arranged in the transition area.

In one embodiment, the heating assembly is divided into a hot area, two cold areas and two transition areas along a length direction of the substrate, the hot area is located at the center of the substrate, the two cold areas are located at opposite ends of the substrate, the two transition areas are respectively located at two opposite sides of the hot area with each transition area being located between the hot area and a corresponding cold area; wherein the heat generating element is arranged in the hot area, the two electrical contacts are respectively arranged in the two cold areas, the heat insulation structure includes two groups of air cavities, and the two groups of air cavities are respectively arranged in the two transition areas.

In one embodiment, the heating assembly is divided into a hot area, a cold area and a transition area along a length direction of the substrate, the hot area is located at the center of the substrate and extends to one end of the substrate, the cold area is located at the other end of the substrate, the transition area is located between the hot area and the cold area; wherein the heat generating element is arranged in the hot area, the two electrical contacts are arranged in the cold area, the heat insulation structure includes a group of air cavities, and the group of air cavities is arranged in the transition area.

In one embodiment, the substrate includes a first main surface and a second main surface which are oppositely disposed, two directions perpendicular to each other are defined on the substrate parallel to the first main surface or the second main surface: a first direction and a second direction; the substrate includes two opposite first side edges in the first direction and two opposite second side edges in the second direction; in the first direction, each of the air cavities includes two opposite third side edges; in the second direction, each of the air cavities includes two opposite fourth side edges; the two third side edges are parallel to the two first side edges, the two fourth side edges are parallel to the two second side edges.

In one embodiment, in the second direction, the distance between the second side edge and the fourth side edge of the air cavity adjacent to the second side edge is W₁, the distance between the two fourth side edges of each air cavity is W₂, the distance between two adjacent air cavities is W₃, the distance between the two second side edges of the substrate is W, then, W=2W₁+mW₂+(m−1)W₃, (mW₂)/W>40%, W₃/W₁>150%; m is the number of the air cavity, m is a positive integer and m≥1.

In one embodiment, in the first direction X1, the distance between opposite side edges of the hot area is L₁, the distance between the two third side edges of each air cavity is L₂, then L₂/L₁>60%.

In one embodiment, the heating assembly further includes a plurality of release holes, the release hole penetrates through the substrate and is located in the hot area.

The present disclosure provides, in a second aspect, an atomizing core. The atomizing core includes a liquid guiding member, and the atomizing core further includes the heating assembly according to the first aspect of the present disclosure.

The present disclosure provides, in a third aspect, an aerosol generating device which includes a battery assembly, an atomizing chamber, an airflow passage, and the atomizing core according to the second aspect of the present disclosure; wherein the airflow passage is communicated with the atomizing chamber; the airflow passage is configured to discharge an aerosol flowing out of the atomizing chamber to the outside for a user to inhale; the battery assembly is electrically connected to the heat generating element, the battery assembly is configured to provide the heat generating element with electrical energy required to atomize an aerosol-forming substrate.

The heating assembly provided by the disclosure includes a heat generating element, a heat insulation structure (air cavity) and electrical contacts, and the air cavity is arranged between the electrical contacts and the heat generating element. Because the air cavity is filled with air and the thermal conductivity of air is low, therefore, the air cavity can limit heat loss of the hot area and prevent the heat of the hot area from rapidly transferring to the cold area to cause the temperature of the cold area to be too high, thereby not only improving the atomizing efficiency of the atomizing core and the aerosol generating device, but also reducing the heat resistance requirements of the heating assembly, the atomizing core and the aerosol generating device for the electrical contacts.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic cross-sectional view of an aerosol generating device provided by an embodiment of the present disclosure.

FIG. 2 is a plan view of a heating assembly shown in FIG. 1.

FIG. 3 is a schematic diagram showing the resistances of different areas of a heating assembly.

FIG. 4 is a plan view of another heating assembly shown in FIG. 1.

FIG. 5 shows the infrared (IR) characteristics of the heating assembly shown in FIG. 4 at 550° C.

FIG. 6 is a plan view of another heating assembly.

The part names and reference signs shown in the figures are as follows:

aerosol generating device 100    first side edge 3111
atomizing assembly 110           second side edge 3112
housing assembly 10              first main surface A1
liquid storage chamber 13        second main surface A2
liquid injection opening 131     heat insulation structure/air
                                 cavity 314
liquid outlet 132                third side edge 3141
atomizing chamber 14             fourth side edge 3142
smoke outlet 141                 heat generating element 315
battery chamber 15               releasing hole 316
airflow passage 16               electrical contact 317
air outlet 161                   liquid guiding member 32
atomizing core 30                absorbing surface 321
heating assembly 31, 31a, 31b, 31c atomizing surface 322
hot area 301                     battery assembly 40
transition area 302              mouthpiece 50
cold area 303                    heat insulating layer 60
substrate 311                    liquid absorbing member 70

The following specific embodiments will further illustrate the present disclosure in conjunction with the above-mentioned accompanying drawings.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

The following will clearly and completely describe the technical solutions in the embodiments of the present disclosure in conjunction with accompanying FIGS. 1-6. It is apparent that the described embodiments are only some of the embodiments of the present disclosure, but not all of them. Based on the implementation described in the disclosure, all other implementations obtained by persons of ordinary skill in the art without creative efforts should fall within the protection scope of the present disclosure.

It should be noted that when an element is referred to be “connected” to another element, it may be directly connected to the other element or there may be an intervening element therebetween.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the technical field of this disclosure. The terminology used herein in the description of the disclosure is only for the purpose of describing specific implementations, and is not intended to limit the disclosure.

Please refer to FIG. 1, the first embodiment of the present disclosure provides an aerosol generating device 100. The aerosol generating device 100 includes a housing assembly 10, an atomizing core 30 and a battery assembly 40. The atomizing core 30 and the battery assembly 40 are received in the housing assembly 10, and the battery assembly 40 is electrically connected to the atomizing core 30.

The housing assembly 10 includes a liquid storage chamber 13, an atomizing chamber 14, a battery chamber 15, and an airflow passage 16.

In one embodiment, the aerosol generating device 100 further includes an atomizing assembly 110. Specifically, the atomizing assembly 110 includes the liquid storage chamber 13, the atomizing chamber 14 and the atomizing core 30. Further, the aerosol generating device 100 may also include the battery chamber 15, the airflow passage 16, the atomizing assembly 110 and the battery assembly 40.

In other embodiments, the battery chamber 15 may also not be included in the housing assembly 10, but is detachably installed with the housing assembly 10. That is, the battery assembly 40 and the atomizing assembly 110 are detachably installed.

It can be understood that, in other embodiments, the atomizing assembly 110 may be provided separately from the liquid storage chamber 13. For example, the atomizing assembly 110 is installed with the battery assembly 40, and the liquid storage device with the liquid storage chamber 13 is provided separately.

The liquid storage chamber 13 is in communication with the atomizing chamber 14, and the atomizing chamber 14 is in communication with the airflow passage 16. The liquid storage chamber 13 is configured for storing e-liquid. The atomizing chamber 14 is configured for receiving the atomizing core 30. The battery chamber 15 is configured for receiving the battery assembly 40. The airflow passage 16 is configured to discharge the smoke flowing out of the atomizing chamber 14 to the outside for inhalation by the user.

In one embodiment, a liquid injection opening 131 is formed on the outer wall of the liquid storage chamber 13. A liquid outlet 132 is formed on the inner wall of the liquid storage chamber 13. The liquid injection opening 131 is configured for injecting e-liquid into the liquid storage chamber 13. The liquid outlet 132 is in fluid communication with the atomizing core 30. The liquid storage chamber 13 is in communication with the atomizing chamber 14 through the liquid outlet 132. The e-liquid in the liquid storage chamber 13 enters the atomizing core 30 through the liquid outlet 132, and the atomizing core 30 is configured to atomize the e-liquid to generate smoke.

A smoke outlet 141 is formed on the wall of the atomizing chamber 14. The atomizing chamber 14 is in communication with the airflow passage 16 through the smoke outlet 141. The smoke outlet 141 is configured to enable the smoke formed by the e-liquid entering the atomizing core 30 and being atomized by the atomizing core 30 to flow into the airflow passage 16.

An air outlet 161 is provided on the wall of the airflow passage 16. The air outlet 161 is configured to enable the smoke to flow from the airflow passage 16 to the outside for the user to inhale.

In other embodiments, the housing assembly 10 is also formed with an air inlet (not shown). When using the above-mentioned aerosol generating device 100, the external air enters from the air inlet, the smoke obtained through atomization by the atomizing core passes through the airflow passage 16 with the airflow and is exported from the air outlet 161 for the user to inhale.

Specifically, the atomizing core 30 is configured to atomize the e-liquid delivered to the atomizing core 30 into smoke. The atomizing core 30 includes a heating assembly 31 and a liquid guiding member 32. The heating assembly 31 is provided on the liquid guiding member 32, the liquid guiding member 32 is fixed on the inner wall of the atomizing chamber 14 and is in fluid communication with the liquid outlet 132. The liquid guiding member 32 is configured to transmit the e-liquid in the liquid storage chamber 13 to the heating assembly 31 and store the e-liquid temporarily. The liquid guiding member 32 includes an absorbing surface 321 and an atomizing surface 322. The absorbing surface 321 faces the liquid outlet 132, while the atomizing surface 322 is opposite to the absorbing surface 321. The heating assembly 31 is fixed on the atomizing surface 322 of the liquid guiding member 32 to heat and atomize the e-liquid transmitted from the liquid guiding member 32 to the heating assembly 31.

Specifically, the heating assembly 31 is provided on the liquid guiding member 32 by directly fixing, wrapping, winding and the like. In this embodiment, the heating assembly 31 is directly fixed on the liquid guiding member 32.

The liquid guiding member 32 is an element having the function of absorbing e-liquid and/or transporting e-liquid, such as cotton, glass fiber, porous ceramics and the like.

The battery assembly 40 is received in the battery chamber 15 and electrically connected to the heating assembly 31. The battery assembly 40 is configured to provide the heating assembly 31 with electric energy required to atomize the e-liquid.

In this embodiment, the aerosol generating device 100 further includes a mouthpiece 50. The mouthpiece 50 is in communication with the airflow passage 16 through the air outlet 161. The smoke flowing out through the air outlet 161 of the airflow passage 16 flows out through the mouthpiece for the user to inhale. In other embodiments, the aerosol generating device 100 may not include the mouthpiece 50.

In another embodiment, the aerosol generating device 100 further includes a heat insulating layer 60. The heat insulating layer 60 is disposed on the inner wall of the airflow passage 16. The heat insulating layer 60 is beneficial to preventing the heat loss in the airflow passage 16, thereby preventing the smoke from rapidly cooling and condensing into e-liquid on the inner wall of the airflow passage 16 caused by the rapid temperature drop in the airflow passage 16.

In another embodiment, the aerosol generating device 100 further includes a liquid absorbing member 70. The liquid absorbing member 70 is arranged on the heat insulating layer 60, and the liquid absorbing member 70 is configured to absorb condensed e-liquid. Specifically, the liquid absorbing member 70 is a hollow columnar or other shape. The liquid absorbing member 70 is made of porous materials, such as superabsorbent resin, sponge, cotton, paper, porous ceramics or other porous materials.

In another embodiment, the aerosol generating device 100 further includes a liquid absorbing member 70. The liquid absorbing member 70 is arranged on the inner wall of the airflow passage 16, which is not shown.

Please refer to FIG. 2, the first embodiment of the present disclosure provides a heating assembly 31a. The heating assembly 31a includes a substrate 311 and a heat insulation structure 314, at least one heat generating element 315 and at least two electrical contacts 317 formed on the substrate 311, wherein the heat insulation structure 314 is located between the heat generating element 315 and the electrical contacts 317. The heat generating element 315 is configured to generate heat, so as to heat and atomize the e-liquid transmitted from the liquid guiding member 32 to the heating assembly 31a. The electrical contacts 317 are electrically connected to the heat generating element 315. The heat insulation structure 314 is configured to reduce or prohibit heat transfer between the electrical contacts 317 and the heat generating element 315, so as to limit the heat loss caused by the heat generating element 315, and prevent the heat generated by the heat generating element 315 from rapidly transferring to the electrical contacts 317 to cause the temperature of the electrical contacts 317 to be too high. The forms of heat transfer include radiation, conduction, and convection. In this embodiment, the heat generating element 315 is electrically connected to the electrical contacts 317 through conductive wires 318. Specifically, the heat generating element 315 is electrically connected to the two electrical contacts 317 through two conductive wires 318, with each conductive wire 318 being connected between the heat generating element 315 and a corresponding electrical contact 317. The conductive wire 318 includes but not limited to metal paste, metal film, and lead. The heat insulation structure 314 may be a structure with low thermal conductivity such as a heat insulating layer, a heat insulating member, or an air cavity. The heat insulating layer may be formed on the surface of the substrate 311, or formed inside the substrate 311. The heat insulation structure 314 is made of a material with low thermal conductivity, or a part of the substrate 311 is directly made of a material with low thermal conductivity. The heat insulation structure 314 can be formed by methods including but not limited to chemical etching, laser etching, electroplating, physical vapor deposition, and chemical vapor deposition. Optionally, the heat insulation structure 314 is an air cavity. Therefore, in this embodiment, the heat insulation structure 314 is at least one group of air cavities 314. Specifically, in this embodiment, the heat insulation structure 314 includes two groups of air cavities 314, and each group of air cavities 314 is consisted of two air cavities 314. The air cavity 314 penetrates through the substrate 311 along the thickness direction of the substrate 311, and the air cavity 314 is in contact with the external air.

The substrate 311 is roughly in the shape of a thin sheet or a thin plate, and has a first main surface A₁ and a second main surface A₂ which are oppositely arranged. It can be understood that the first main surface A₁ and the second main surface A₂ may be circular, elliptical, or polygonal such as triangular, rectangular, trapezoidal, pentagonal, etc., which are not limited here. Optionally, the first main surface A₁ and the second main surface A₂ are substantially planar.

Specifically, the material for preparing the substrate 311 may be metal oxide, nitride, carbide or the like. Optionally, the substrate 311 is made of ceramic material, and further, the material of the substrate 311 is aluminosilicate.

Two directions perpendicular to each other are defined on the substrate 311 parallel to the first main surface A₁ or the second main surface A₂: the first direction X₁ and the second direction X₂. The substrate 311 includes two opposite first side edges 3111 in the first direction X₁ and two opposite second side edges 3112 in the second direction X₂. In this embodiment, the first main surface A₁ of the substrate 311 is rectangular, and the two first side edges 3111 are perpendicularly connected to the two second side edges 3112. In other embodiments, the first main surface A₁ of the substrate 311 may also be in other polygonal or circular shapes, so that the substrate 311 also includes other side edges, the two first side edges 3111 and the two second side edges 3112 are respectively connected to at least one other side edge. If the cross-section of the substrate 311 is circular, the first side edges 3111 may be simplified as two tangent points in the first direction X₁, and the second side edges 3112 may be simplified as two tangent points in the second direction X₂. A third direction X₃ is defined along the vertical direction of the first main surface A₁, and the third direction X₃ is the thickness direction of the substrate 311.

In this embodiment, the substrate 311 has a thickness of about 0.4 mm, a total width of 12.0 mm, and a thermal conductivity of about 3 Wm⁻¹K⁻¹. In this embodiment, the heating assembly 31a includes two groups of four air cavities 314 and two electrical contacts 317. The two groups of air cavities 314 are respectively arranged on both sides of the heat generating element 315, and an electrical contact 317 is provided on one side of each group of air cavities 314 away from the heat generating element 315. In one embodiment, the heat generating element 315 is arranged at the center of the substrate 311, and the electrical contacts 317 are arranged at the ends of the substrate 311.

In this embodiment, the two air cavities 314 of each group are aligned in the second direction X₂.

Specifically, in the first direction X₁, each of the air cavities 314 includes two opposite third side edges 3141, and in the second direction X₂, each of the air cavities 314 includes two opposite fourth side edges 3142. The two third side edges 3141 are parallel to the two first side edges 3111, and the two fourth side edges 3142 are parallel to the two second side edges 3112.

In this embodiment, the first main surface A₁ of the substrate 311 is rectangular, the two first side edges 3111 are perpendicularly connected to the two second side edges 3112. The cross-section of the air cavity 314 on the first main surface A₁ is also rectangular. The two third side edges 3141 are perpendicularly connected to the two fourth side edges 3142. Specifically, each air cavity 314 is rectangular and has a length extending along the length direction of the substrate 311. In this embodiment, the first direction X₁ is the length direction of the substrate 311, and the second direction X2 is the width direction of the substrate 311.

In other embodiments, the cross-section of the air cavity 314 on the first main surface A₁ may also be in polygonal or circular shapes, and thus the air cavity 314 also includes other side edges, and the two third side edges 3141 and the two fourth side edges 3142 are respectively connected to at least one other side edge. If the cross-section of the air cavity 314 on the first main surface A₁ is circular, the third side edges 3141 can be simplified as two tangent points in the first direction X₁, and the fourth side edges 3142 can be simplified as two tangent points in the second direction X₂.

In the first direction X₁, the heating assembly 31a is divided into at least one cold area 303, at least one transition area 302 and at least one hot area 301, wherein one end of the transition area 302 is connected to the cold area 303, and the other end of the transition area 302 is connected to the hot area 301. Specifically, the cold area 303 refers to the area jointly enclosed by the two second side edges 3112, the extension line RR′ of the third side edge 3141 of at least one air cavity 314 adjacent to the electrical contact 317, and the first side edge 3111 adjacent to the electrical contact 317. The transition area 302 refers to the area jointly enclosed by the two second side edges 3112 and the extension lines RR′ and QQ′ of the two opposite third side edges 3141 of at least one air cavity 314. The hot area 301 refers to the area jointly enclosed by the two second side edges 3112 and the extension lines PP′ and QQ′ of the third side edges 3141 of the air cavities 314 located at opposite sides of the heat generating element 315, or refers to the area jointly enclosed by the two second side edges 3112, the extension line PP′ of the third side edge 3141 of at least one air cavity 314 adjacent to the heat generating element 315, and the first side edge 3111 adjacent to the heat generating element 315. The electrical contact 317 is located in the cold area 303, the air cavity 314 is located in the transition area 302, the heat generating element 315 is located in the hot area 301.

In this embodiment, the heating assembly 31a is divided into two cold areas 303, two transition areas 302 and a hot area 301 along the length direction of the substrate 311, wherein the hot area 301 is located at the center of the substrate 311, the two cold areas 303 are located at opposite ends of the substrate 311, the two transition areas 302 are respectively located at two opposite sides of the hot area 301 with each transition area 302 being located between the hot area 301 and a corresponding cold area 303; the heat generating element 315 is arranged in the hot area 301, the two electrical contacts 317 are respectively arranged in the two cold areas 303, the heat insulation structure 314 includes two groups of air cavities 314, and the two groups of air cavities 314 are respectively arranged in the two transition areas 302. It can be understood that in the present disclosure, a transition area 302 is provided between the hot area 301 and the cold area 303. Thus, during the transfer of heat from the hot area 301 to the cold area 303, due to the existence of the transition area 302, the heat is stopped in the direction of transfer, and the temperature drops sharply, so that the temperature of the cold area 303 is kept at a relatively low level. Optionally, the temperature of the cold area 303 is below 100° C. In this embodiment, the hot area 301 refers to the area enclosed by the two second side edges 3112, the extension lines PP′ and QQ′ of the third side edges 3141 of the air cavities 314 adjacent to the heat generating element 315.

Please continue to refer to FIG. 2, in the second direction X₂, the distance between the second side edge 3112 and the fourth side edge 3142 of the air cavity 314 adjacent to the second side edge 3112 is W₁; the distance between the two fourth side edges 3142 of each air cavity 314 is W₂, the distance between two adjacent air cavities 314 is W₃, the distance between the two second side edges 3112 of the substrate 311 is W; then, W=2W₁+mW₂+(m−1)W₃; optionally, (mW₂)/W>40%, W₃/W₁>150%, so as to ensure that the air cavity 314 has sufficient resistance to heat, wherein m is the number of the air cavity 314, m is a positive integer and m≥1. In this embodiment, m=2.

The cross-sectional area of each of the air cavities 314 on the first main surface A₁ is A₁, the total cross-sectional area of the first main surface A₁ of the substrate 311 is A₂, the ratio of the total cross-sectional area mA₁ of the air cavities 314 to the total cross-sectional area A₂ of the substrate 311 is defined as the quality index E of the heating assembly 31a, wherein the quality index E can reflect the thermal decoupling efficiency of the heating assembly 31a. Optionally, the thickness of the heating assembly 31a may be selected to be 0.1 mm-5 mm, then E=(mA₁)/A₂₉>15%. That is, when the thickness of the heating assembly 31a is 0.1 mm to 5 mm, the quality index E of the air cavities 314 must be greater than 15%, so as to ensure that the air cavities 314 can effectively stop the heat of the hot area 301 from

transferring to the cold area 303. Please continue to refer to FIG. 2, in one embodiment, in the first direction X₁, the distance between opposite side edges of the hot area 301 is L₁, the distance between the two third side edges 3141 of each air cavity 314 is L₂; optionally, L₂/L₁>60%. Optionally, L₂ is 6 mm. This structure can achieve effective thermal decoupling.

The heat generating element 315 can be an embedded thick film resistance heater, a heating coating, a heating coil, a heating sheet, a heating net and the like. Specifically, the material for preparing the heat generating element 315 may be noble metal or common metal or conductive oxide. Specifically, the noble metal may be ruthenium, platinum, gold, silver, palladium or their alloys. The common metal can be copper or nickel and the like. The conductive oxide may be ruthenium oxide or the like. In this embodiment, the heat generating element 315 is made of platinum. Specifically, the thermal conductivity of the heat generating element 315 is about 72 Wm⁻¹K⁻¹. In this embodiment, the heat generating element 315 is two embedded thick film resistance heaters. Specifically, the heat generating element 315 has a thickness of 0.01 mm and a width of 0.6 mm.

In the first direction X₁, the distance between the first side edge 3111 and the third side edge 3141 of the air cavity 314 adjacent to the first side edge 3111 is defined as L₅, then L₅ should be long enough to facilitate the installation of the electrical contact 317. The area of the electrical contact 317 must be large enough to be compatible with standard electrical contacts in the atomizing core 30 of the aerosol generating device 100.

The heating assembly 31a further includes a plurality of releasing holes 316. The releasing hole 316 penetrates through the substrate 311 along the third direction X₃ and is located in the hot area 301. The releasing holes 316 are arranged corresponding to the liquid guiding member 32, and are configured for releasing the smoke generated by the atomization of the heat generating element 315 into the atomizing chamber 14.

Please continue to refer to FIG. 2, the cross-sectional area of each releasing hole 316 is define as A3, then optionally, the ratio of the total cross-sectional area nA3 of the releasing holes 316 to the total cross-sectional area A₂ of the substrate satisfies: 0.03%≤nA₃/A₂≤9.00%, wherein n is the number of the releasing holes 316, n is a positive integer and n>0.

Specifically, the ratio of the total cross-sectional area of the releasing holes 316 to the total cross-sectional area of the substrate 311 is a quality factor of the releasing holes 316 and can be used to characterize the effectiveness of the releasing holes 316. It should be noted that, the cross-section corresponding to the cross-sectional area is parallel to the first main surface A₁ or the first main surface A₂.

The radius of each releasing hole 316 is defined as r₁, then optionally, 0.01≤r₁/L₁0.1. Such arrangement is beneficial to release the smoke generated by the atomization of the heat generating element 315 into the atomizing chamber 14.

In one embodiment, in the first direction X₁, the shortest distance from the edge of the releasing hole 316 adjacent to the air cavity 314 to the edge of the adjacent air cavity 314 is defined as L₃, L₃/L₁>10%. In one embodiment, in the second direction X₂, the distance from the edge of the releasing hole 316 adjacent to the second side edge 3112 to the adjacent second side edge 3112 is defined as L₄, L₄/L₁>10%. Such arrangement is beneficial to release the smoke generated by the atomization of the heat generating element 315 into the atomizing chamber 14.

Please refer to FIG. 4, a heating assembly 31b is provided in the second embodiment of the present disclosure, the structure of the heating assembly 31b is similar to that of the heating assembly 31a, the only difference is that the air cavities 314 are only arranged on one side of the heat generating element 315. The electrical contacts 317 are all located at one end of the substrate 311, and are not separately located at both ends of the substrate 311, so that the heating assembly 31b has a larger heating area. Specifically, in this embodiment, the heating assembly 31b is divided into a hot area 301, a cold area 303 and a transition area 302 along the length direction of the substrate 311, the hot area 301 is located at the center of the substrate 311 and extends to one end of the substrate 311, the cold area 303 is located at the other end of the substrate 311, the transition area 302 is located between the hot area 301 and the cold area 303; wherein the heat generating element 315 is arranged in the hot area 301, the two electrical contacts 317 are arranged in the cold area 303, the heat insulation structure 314 includes a group of air cavities 314, and the group of air cavities 314 is arranged in the transition area 303. Specifically, the group of air cavities 314 is consisted of two air cavities 314. In this embodiment, each air cavity 314 is rectangular and has a length extending along the length direction of the substrate 311.

In this embodiment, please refer to FIG. 2 and FIG. 3, the resistance value of the heating assembly 31a can be calculated by the following formulas:

$\begin{array}{cc}{R}_{\mathrm{thermal}}=\frac{L_{\mathrm{bridge}}}{k_n·\left(W_i·T\right)},& \mathrm{Formula}1\end{array}$ $\begin{array}{cc}\frac{1}{R_{\mathrm{bridge}}}=\frac{2}{R_{\mathrm{airi}}}+\frac{2}{R_{sidei}}+\frac{1}{R_{\mathrm{center}}}+\frac{2}{R_{Pti}},& \mathrm{Formula}2\end{array}$ $\mathrm{wherein}\frac{1}{R_{\mathrm{air}1}}=\frac{1}{R_{\mathrm{air}2}},\frac{1}{R_{side1}}=\frac{1}{R_{side2}},\frac{1}{R_{\mathrm{Pt}1}}=\frac{1}{R_{\mathrm{Pt}2}}$

wherein R_thermal is the absolute thermal resistance, L_bridge is the length of the air cavity 314 in the first direction X₁ (that is, L₂ in FIG. 2), kn is the thermal conductivity of the material or the air, T is the thickness of the heating assembly 31a, W_i is the width of each part, and in the present embodiment, W_i corresponds to W₁, W₂, and W₃ described above. Therefore, in this embodiment, the total thermal resistance R_bridge of the heating assembly 31a is composed of several resistances connected in parallel, including the resistance (R_air1+R_air2) of the two groups of air cavities 314, the resistance R_center of the substrate 311 between the two groups of air cavities 314, the resistance R_side1 and resistance R_side2 of the substrate 311 between the air cavities 314 and the corresponding two first side edges 3111, and the resistances R_Pt1 and R_Pt2 of the conductive wires 318. In this embodiment, the total width W of the substrate 311 is 12.0 mm, W₁, W₂, W₃ are 3 mm, 4 mm and 1 mm respectively, the embedded thick film resistance heater has a thickness of 0.01 mm and a width of 0.6 mm, the length of the air cavity 314 is 6 mm. The substrate 311 has a thickness of about 0.4 mm, a total width of 12.0 mm, and a thermal conductivity of about 3 Wm⁻¹K⁻¹. The material of the embedded thick film resistance heater is platinum, and the thermal conductivity of the embedded thick film resistance heater is about 72 Wm⁻¹K⁻¹. The thermal conductivity of the air in the air cavity 314 is about 0.04 Wm⁻¹K⁻¹. In this embodiment, the thermal resistance of each air cavity 314 is 463 KW⁻¹.

Please refer to FIG. 5, FIG. 5 is an IR characteristic diagram of the heating assembly 31b shown in FIG. 4 when working at 550° C. It can be seen from the figure that the air cavity 314 is used to realize the transition between the heat generating element 315 and the electrical contacts 317 of the heating assembly 31b, so that the temperature of the cold area 303 can be maintained below 100° C., while the hot area of the heating assembly 31b is maintained at a temperature of 550° C. to 560° C. This shows that the heating assembly 31b has good heating uniformity and a lower level of heat transfer, so that the hot area 301 where the heat generating element 315 is located and the cold area 303 where the electrical contacts 317 are located can be effectively isolated.

Please refer to FIG. 6, a heating assembly 31c is provided in the third embodiment of the present disclosure, the structure of the heating assembly 31c is similar to that of the heating assembly 31b, the only difference is that the two air cavities 314 are aligned in the first direction X₁. Specifically, in this embodiment, each air cavity 314 is rectangular and has a length extending along the width direction of the substrate 311.

The heating assembly provided by the disclosure includes a heat generating element, a heat insulation structure (air cavity) and electrical contacts, and the air cavity is arranged between the electrical contacts and the heat generating element. Because the air cavity is filled with air and the thermal conductivity of air is low, therefore, the air cavity can limit heat loss of the hot area and prevent the heat of the hot area from rapidly transferring to the cold area to cause the temperature of the cold area to be too high, thereby not only improving the atomizing efficiency of the atomizing core and the aerosol generating device, but also reducing the heat resistance requirements of the heating assembly, the atomizing core and the aerosol generating device for the electrical contacts.

The present disclosure also provides a method for manufacturing a heating assembly, including:

Step 1: forming a substrate by casting.

A mixture of ceramic powder and organic components is cast into a strip-shaped substrate with a thickness of 0.2 mm to 2 mm.

Step 2: processing the substrate to form a desired structure.

The strip-shaped substrate is cut into a desired size so as to be used as the substrate for a heating assembly;

A heat insulation structure is formed on the substrate by laser cutting or stamping process, and the heat insulation structure may be an air cavity, or a heat insulating member, and the like.

Optionally, this step may also include forming releasing holes and/or electrical through holes on the substrate by laser cutting or stamping.

Step 3: printing a heat generating element and electrical contacts on the substrate.

This step includes printing the heat generating element (resistance heating material) of a required pattern and the electrical contacts on the substrate to form a semi-finished product by screen printing process.

The electrical contacts include electrical pads. Further, this step also includes printing conductive wires on the substrate, the conductive wires are configured to connect the heat generating element to the electrical contacts.

Step 4: drying the semi-finished product obtained in step 3.

Step 5: stacking the semi-finished products obtained after drying in step 4, wherein the heat generating element is embedded inside the substrate, and the electrical contacts are located on the surface of the substrate.

Step 6: thermally compressing the semi-finished products obtained in step 5 at a temperature of 40° C.-100° C., and then sintering at a high temperature (800° C.-1600° C.) to remove organic components and finally to become a whole.

The above descriptions are only preferred embodiments of the present application, and do not limit the present application in any form. Although the present application has been disclosed above with preferred embodiments, it is not intended to limit the present application. The persons skilled in the art may make some changes or modifications by using the technical content disclosed above, and if they do not depart from the technical content of the present application, any simple modifications, equivalent changes and modifications made to the above embodiments still fall within the protection scope of the technical solution of the present application.

Claims

1. A heating assembly for being used in an aerosol generating device, comprising: a substrate;at least one heat generating element, wherein the heat generating element is formed on the substrate;at least two electrical contacts, wherein the electrical contacts are formed on the substrate, the electrical contacts are electrically connected to the heat generating element;at least one heat insulation structure, wherein the heat insulation structure is formed on the substrate and located between the heat generating element and the electrical contacts.

2. The heating assembly according to claim 1, wherein the heat generating element is arranged at the center of the substrate, and the electrical contacts are arranged at the ends of the substrate.

3. The heating assembly according to claim 2, wherein the heat insulation structure is located on one side of the heat generating element, and the at least two electrical contacts are located at one end of the substrate away from the heat generating element.

4. The heating assembly according to claim 1, wherein the heat insulation structure is air cavity.

5. The heating assembly according to claim 4, wherein the air cavity penetrates through the substrate along a thickness direction of the substrate.

6. The heating assembly according to claim 4, wherein a group of air cavities are respectively formed on both sides of each heat generating element, and a side of each group of air cavities away from the heat generating element is formed with one of the electrical contacts.

7. The heating assembly according to claim 1, wherein the heating assembly is divided into a cold area, a hot area and a transition area, the heat generating element is arranged in the hot area, and the electrical contacts are arranged in the cold area, the heat insulation structure is arranged in the transition area.

8. The heating assembly according to claim 1, wherein the heating assembly is divided into a hot area, two cold areas and two transition areas along a length direction of the substrate, the hot area is located at the center of the substrate, the two cold areas are located at opposite ends of the substrate, the two transition areas are respectively located at two opposite sides of the hot area with each transition area being located between the hot area and a corresponding cold area; wherein the heat generating element is arranged in the hot area, the two electrical contacts are respectively arranged in the two cold areas, the heat insulation structure includes two groups of air cavities, and the two groups of air cavities are respectively arranged in the two transition areas.

9. The heating assembly according to claim 1, wherein the heating assembly is divided into a hot area, a cold area and a transition area along a length direction of the substrate, the hot area is located at the center of the substrate and extends to one end of the substrate, the cold area is located at the other end of the substrate, the transition area is located between the hot area and the cold area; wherein the heat generating element is arranged in the hot area, the two electrical contacts are arranged in the cold area, the heat insulation structure includes a group of air cavities, and the group of air cavities is arranged in the transition area.

10. The heating assembly of claim 4, wherein the substrate comprises a first main surface and a second main surface which are oppositely disposed, two directions perpendicular to each other are defined on the substrate parallel to the first main surface or the second main surface: a first direction and a second direction; the substrate includes two opposite first side edges in the first direction and two opposite second side edges in the second direction; in the first direction, each of the air cavities includes two opposite third side edges; in the second direction, each of the air cavities includes two opposite fourth side edges; the two third side edges are parallel to the two first side edges, the two fourth side edges are parallel to the two second side edges.

11. The heating assembly of claim 10, wherein in the second direction, the distance between the second side edge and the fourth side edge of the air cavity adjacent to the second side edge is W1, the distance between the two fourth side edges of each air cavity is W2, the distance between two adjacent air cavities is W3, the distance between the two second side edges of the substrate is W, then, W=2W1+mW2+(m−1)W3, (mW2)/W>40%, W3/W1>150%; m is the number of the air cavity, m is a positive integer and m≥1.

12. The heating assembly according to claim 7, wherein, in the first direction X1, the distance between opposite side edges of the hot area is L1, the distance between the two third side edges of each air cavity is L2, then L2/L1>60%.

13. The heating assembly according to claim 7, further comprising a plurality of release holes, the release hole penetrates through the substrate and is located in the hot area.

14. An atomizing core comprising a liquid guiding member, wherein the atomizing core further comprises the heating assembly of claim 1.

15. An aerosol generating device comprising a battery assembly, an atomizing chamber, an airflow passage, and the atomizing core according to claim 14; wherein the airflow passage is communicated with the atomizing chamber; the airflow passage is configured to discharge an aerosol flowing out of the atomizing chamber to the outside for a user to inhale; the battery assembly is electrically connected to the heat generating element, the battery assembly is configured to provide the heat generating element with electrical energy required to atomize an aerosol-forming substrate.