Aerosol-generating device

Abstract

The present invention relates to the technical field of electronic atomization, in particular to an aerosol generating device and a heating assembly, the heating assembly comprising: a support tube defining a heating chamber for accommodating at least a portion of an aerosol generating product comprising an aerosol-forming substrate; and the planar microwave antenna is configured to be of a sheet-shaped or film-layer structure and is arranged on the outer surface of the supporting pipe in a surrounding manner, and the planar microwave antenna is used for emitting radio frequency energy and conducting the radio frequency energy to the heating cavity when being electrified, so that the aerosol-forming substrate in the aerosol-generating product in the heating cavity is heated to generate aerosol. Compared with an existing microwave antenna coil which is etched on the surface of the supporting tube through winding or electroplating, the planar microwave antenna is beneficial to improving the heating efficiency and reducing the complexity and the cost of a product structure.

Description

[0001] This divisional application is based on a Chinese patent application with application number 202410774116.4 and with the title "Aerosol-generating device and heating assembly", filed on June 14, 2024. TECHNICAL FIELD

[0002] The present application relates to the technical field of electronic atomization, in particular to an aerosol-generating device and a heating assembly. BACKGROUND

[0003] The aerosol-generating device heats to a temperature that can generate aerosol from an aerosol-generating article but is insufficient to burn, so that the aerosol-forming substrate in the aerosol-generating article can generate the aerosol required by the user without burning.

[0004] As an example of the prior art, the aerosol-generating device is provided with a spiral microwave antenna coil on the outer surface of the support tube. The coil can emit electromagnetic waves to form a microwave electromagnetic field when powered on, and the microwave energy is rapidly converted into heat to heat the aerosol-generating substrate under the joint action of the microwave electromagnetic field and the aerosol-forming substrate. However, the spiral coil microwave antenna as a radiation source has low heating efficiency and energy utilization, which affects the heating speed of the heating assembly and the endurance of the aerosol-generating device. In addition, the microwave antenna coil needs to be wound or electroplated and etched on the surface of the support tube, which increases the complexity and cost of the product structure. SUMMARY

[0005] In view of the deficiencies of the prior art, the present application provides an aerosol-generating device and a heating assembly thereof for heating an aerosol-generating article, aiming to solve the problems of low heating efficiency of the spiral coil microwave antenna and increased complexity and cost of the product structure.

[0006] To achieve the above-mentioned purpose, the present application adopts the following technical solutions:

[0007] One of the embodiments of the present application provides a heating assembly for heating an aerosol-generating article, comprising:

[0008] a support tube defining a heating cavity for accommodating at least a portion of an aerosol-generating article comprising an aerosol-forming substrate; and a planar microwave antenna configured in a sheet or film layer structure and arranged around the outer surface of the support tube, the planar microwave antenna being configured to emit radio frequency energy when powered on and being conducted to the heating cavity, thereby heating the aerosol-forming substrate in the aerosol-generating article in the heating cavity to generate an aerosol.

[0009] One of the embodiments of the present application provides a heating assembly, wherein the planar microwave antenna has opposite first and second side edges in a circumferential direction, and the first and second side edges do not overlap each other to form a gap.

[0010] One of the embodiments of the present application provides a heating assembly, wherein the planar microwave antenna is provided with a first through slot extending from the first side edge towards the second side edge, and the first through slot is spaced apart from the second side edge.

[0011] One of the embodiments of the present application provides a heating assembly, wherein the planar microwave antenna is further provided with a second through slot extending from the second side edge towards the first side edge, the second through slot is spaced apart from the first side edge, and the second through slot is longitudinally staggered with the first through slot.

[0012] One of the embodiments of the present application provides a heating assembly, wherein the spacing between the first through slot and the second side edge is greater than the spacing between the second through slot and the first side edge.

[0013] One of the embodiments of the present application provides a heating assembly, wherein the planar microwave antenna is provided with first and second through slots extending in the circumferential direction or the width direction and parallel to each other, and part of the support tube is exposed to the first and second through slots.

[0014] One of the embodiments of the present application provides a heating assembly, wherein the width of the first through slot is greater than the width of the second through slot.

[0015] One of the embodiments of the present application provides a heating assembly, wherein the planar microwave antenna is Z-shaped or F-shaped.

[0016] One of the embodiments of the present application provides a heating assembly, wherein the planar microwave antenna includes a ground end and a feed end, and the ground end and the feed end are located on opposite sides of the opening of the first through slot.

[0017] One of the embodiments of the present application provides a heating assembly, wherein the planar microwave antenna includes a ground end and a feed end, and the ground end and the feed end are both located on the first side edge, or the ground end and the feed end are both located on the second side edge.

[0018] One of the embodiments of the present application provides a heating assembly, wherein the height of the planar microwave antenna along the longitudinal direction of the support tube is 15-19 mm, or the width of the planar microwave antenna after being developed in the circumferential direction is 20-29 mm.

[0019] One of the embodiments of the present application provides a heating assembly, wherein the support tube is a cylindrical structure made of quartz, ceramic or plastic.

[0020] One of the embodiments of the present application provides a heating assembly, the planar microwave antenna includes a flexible circuit board, or the conductor material of the planar microwave antenna includes cupronickel.

[0021] One of the embodiments of the present application provides a heating assembly, the transmission efficiency of the radio frequency energy of the planar microwave antenna is greater than 90%, or the return loss of the planar microwave antenna is greater than 10.

[0022] One of the embodiments of the present application provides a heating assembly, the heating frequency of the planar microwave antenna is 2430MHz-2460MHz.

[0023] One of the embodiments of the present application provides a heating assembly, the planar microwave antenna is attached to the outer surface of the support tube, or the conductor material of the planar microwave antenna is integrated on the support tube.

[0024] One of the embodiments of the present application provides an aerosol generating device, including a battery assembly and the heating assembly provided by any one of the above embodiments, the battery assembly provides electric energy to the heating assembly.

[0025] The aerosol generating device and the heating assembly for heating the aerosol generating article described in the above embodiments have the following beneficial effects: the heating assembly involved in the present application uses a planar microwave antenna, the planar microwave antenna is arranged on the outer surface of the support tube, so that the planar microwave antenna can surround the heating cavity, the planar microwave antenna has a larger radiation source compared with a spiral linear antenna, the planar microwave antenna conducts the radio frequency energy radially into the heating cavity to radiatively heat the aerosol generating article in the heating cavity, compared with the existing microwave antenna coil which is wound or etched on the surface of the support tube by electroplating, the heating efficiency of the microwave antenna is improved; on the other hand, the planar microwave antenna arranged on the outer surface of the support tube has a very small thickness, which is beneficial to reducing the volume of the heating assembly and the miniaturization of the aerosol generating device. In addition, the planar microwave antenna in the heating assembly of the present application can be combined with the support tube in a winding and attaching manner, which reduces the complexity of the product structure and the assembly cost. BRIEF DESCRIPTION OF DRAWINGS

[0026] Figure 1 is a perspective view of the aerosol generating device of the embodiment of the present application from one viewing angle;

[0027] Figure 2 is a perspective view of the aerosol generating device of the embodiment of the present application from another viewing angle;

[0028] Figure 3 is a schematic view of the internal structure of the aerosol generating device of the embodiment of the present application;

[0029] Figure 4is a sectional view of an aerosol generating device according to an embodiment of the present application;

[0030] Figure 5 is an assembly view of a heating assembly according to an embodiment of the present application;

[0031] Figure 6 is an expanded schematic view of a planar microwave antenna according to an embodiment of the present application;

[0032] Figure 7 is a signal transmission schematic view of a microwave generating circuit according to an embodiment of the present application;

[0033] Figure 8 is Figure 7 a signal transmission schematic view of a microwave generating circuit according to an embodiment of the present application;

[0034] Figure 9 is Figure 7 a signal transmission schematic view of a microwave generating circuit according to an embodiment of the present application;

[0035] Figure 10 is an electric field simulation view of a planar microwave antenna according to an embodiment of the present application;

[0036] Figure 11 is a magnetic field simulation view of a planar microwave antenna according to an embodiment of the present application.

[0037] BRIEF DESCRIPTION OF DRAWINGS

[0038] 1, aerosol generating device; 11, heating assembly; 111, planar microwave antenna; 1111, first through slot; 1112, second through slot; 1113, ground terminal; 1114, feed terminal; 1115, first side edge; 1116, second side edge; 1117, first portion; 1118, second portion; 1119, third portion; 112, support tube; 1121, heating cavity; 113, thermal insulation member; 12, housing; 120, charging hole; 121, first cavity; 122, second cavity; 123, third cavity; 13, housing cover; 130, insertion opening; 14, support; 15, power supply unit; 16, circuit board; 17, control button; 18, aerosol generating article; 181, filter portion; 182, smoking portion. DETAILED DESCRIPTION

[0039] The present application will be further described below in conjunction with the accompanying drawings and specific embodiments.

[0040] Please refer to Figure 1 An embodiment of the present application provides an aerosol generating device 1, which can be used to heat an aerosol generating article 18 to make the aerosol generating article 18 emit aerosol for a user to smoke.

[0041] As used herein, the term "aerosol-generating article 18" refers to an article that includes an aerosol-forming substrate, which is intended to be heated rather than combusted to release volatile compounds that can form an aerosol. Aerosols formed by heating an aerosol-forming substrate can contain fewer components known to be harmful than aerosols produced by combustion or pyrolytic degradation of the aerosol-forming substrate. In one embodiment, the aerosol-generating article 18 can be removably coupled to the aerosol-generating device 1.

[0042] The aerosol-forming substrate is preferably a tobacco-containing material from which volatile compounds are released upon heating; it can also be a non-tobacco material suitable for electrically heated smoking. The aerosol-forming substrate is preferably a solid substrate, which can include one or more of a powder, granules, shreds, strips, or a sheet of one or more of tobacco leaves, tobacco homogenate, expanded tobacco; or, the solid substrate can contain additional volatile flavour compounds, either tobacco or non-tobacco, to be released upon heating of the substrate. A suitable aerosol-forming substrate can be a cigarette filled with tobacco material inside.

[0043] In other embodiments, the term "aerosol-generating article 18" refers to a container or cartridge capable of holding an aerosol-forming substrate, or other carrier capable of holding an aerosol-forming substrate. The aerosol-forming substrate contained by the aerosol-generating article 18 can be a liquid composition or a combination of a liquid composition and a solid composition. Suitable aerosol-forming substrates include, but are not limited to, polyhydric alcohols such as triethylene glycol, 1,3-butanediol, and glycerol; esters of polyhydric alcohols such as glycerol mono-, di-, or triacetate; and fatty acid esters of mono-, di-, or polybasic carboxylic acids such as dimethyl dodecanedioate and dimethyl tetradecanedioate. A preferred aerosol-forming substrate is a polyhydric alcohol or mixture thereof, such as triethylene glycol, 1,3-butanediol, and most preferably glycerol. The aerosol-forming substrate can include other additives and ingredients such as flavourings. In some alternative examples, the aerosol-generating article 18 further includes a liquid retaining element for absorbing and retaining the liquid substrate, suitable liquid retaining elements are made of flexible fibres such as cotton fibres, non-woven fabric, sponge, etc., in other examples, the liquid retaining element is made of a porous material such as microporous ceramic, microporous glass, or microporous metal.

[0044] As used herein, the term "aerosol-generating device 1" is a device that engages or interacts with an aerosol-generating article 18 to heat or vaporize a substrate material within the aerosol-generating article 18 to form an inhalable aerosol.

[0045] The aerosol-generating device 1 includes a heating assembly 11 for heating the aerosol-forming substrate of the aerosol-generating article 18 to generate an aerosol.

[0046] As Figures 1 to 4As shown, an embodiment of the present application provides an aerosol generating device 1, which comprises a housing 12 and a cover 13, the cover 13 covers the housing 12 to form a cavity, and the aerosol generating device 1 further comprises a heating assembly 11, a support 14, a power supply unit 15, and a circuit board 16 accommodated in the cavity; wherein the heating assembly 11 comprises a planar microwave antenna 111 and a support tube 112.

[0047] The support 14 is fixedly installed on the housing 12, and the heating assembly 11, the power supply unit 15, and the circuit board 16 are installed on the support 14.

[0048] As shown, Figure 3 and Figure 4 As shown, the support 14 divides the inside of the housing 12 into a first cavity 121 and a second cavity 122, the circuit board 16 is installed in the first cavity 121, and the power supply unit 15 is installed in the second cavity 122. In addition, the support 14 and the cover 13 form a third cavity 123, and the heating assembly 11 is installed in the third cavity 123.

[0049] As shown, Figure 3 and Figure 4 As shown, in some embodiments, the heating assembly 11 further comprises a heat insulation member 113, the heat insulation member 113 is installed on the support 14, the support tube 112 is fixed inside the heat insulation member 113, and the heat insulation member 113 can limit the heat from being transmitted to the housing 12 in the radial direction, thereby improving the heating efficiency of the heating assembly 11 and avoiding the heat from being transmitted to the housing 12 to affect the user experience.

[0050] The heat insulation member 113 is preferably made of a plastic material with good heat insulation performance, and a suitable material can be PEEK. PEEK (polyether ether ketone) is a high-performance thermoplastic with high strength and high temperature resistance, easy to process, high wear resistance and chemical resistance, and performs well in high temperature environments. Alternatively, the heat insulation member 113 can be configured in the form of a vacuum tube. Since the vacuum tube has a vacuum state inside, and since the vacuum has heat insulation effect, the heat of the heating assembly 11 can be isolated by the vacuum tube, so that the heat of the heating assembly 11 cannot be transmitted to the housing 12. Alternatively, the heat insulation member 113 is covered or surrounded by aerogel around the periphery of the support tube 112, thereby providing thermal insulation. In some exemplary embodiments, the heat insulation member 113 surrounds the periphery of the planar microwave antenna 111, so that the planar microwave antenna 111 is bent and kept as a non-closed ring, and the heat insulation member 113 can also provide support so that the planar microwave antenna 111 can be kept at a specific position on the support tube 112 and cannot be moved.

[0051] The power supply unit 15 is configured to supply power to the working circuit on the circuit board 16, and the working circuit on the circuit board 16 is configured to control the planar microwave antenna 111 to start or stop working and the size of the output microwave frequency. In some embodiments, the circuit board 16 is further connected with a control button 17 exposed outside the cover 13 through a button hole of the cover 13, so that a user can control the planar microwave antenna 111 to start or stop working through the control button 17.

[0052] In an embodiment of the present application, the power supply unit 15 includes a rechargeable or non-rechargeable battery, and in some embodiments, the power supply is a lithium ion battery. Alternatively, the power supply can be a nickel-metal hydride battery, a nickel-cadmium battery, or a lithium-based battery, such as a lithium cobalt, lithium iron phosphate, lithium titanate, or lithium polymer battery.

[0053] In an embodiment of the present application, the power supply unit 15 is a rechargeable battery, and therefore the circuit board 16 is further provided with a charging module, and the housing 12 is provided with a charging hole 120 through which a charging connector can be plugged into the charging module to form a charging state.

[0054] The support tube 112 defines a heating cavity 1121 for accommodating an aerosol generating article, and the planar microwave antenna 111 is configured in a sheet or film structure and is arranged around the outer surface of the support tube 112. The planar microwave antenna 111 is configured to emit radio frequency energy when powered on and conduct to the heating cavity 1121, thereby heating the aerosol-forming substrate in the aerosol generating article in the heating cavity 1121 to generate an aerosol. It can be understood that different substrate materials in the aerosol generating article 18 can absorb microwave radio frequency energy to different extents, and the substrate materials and the microwave electromagnetic field are coupled to each other to achieve energy conversion. The process of microwave electromagnetic field energy conversion includes but is not limited to ion conduction, dipole rotation, and interface polarization. The aerosol-forming substrate absorbs microwave electromagnetic field energy through ion conduction, dipole rotation, and other methods and converts it into heat, thereby heating the entire aerosol-forming substrate to generate an aerosol. Compared with traditional heating methods, the heating method of the present application does not rely on heat transfer and convection radiation, reduces the temperature gradient in the aerosol-forming substrate during heating, and has the advantages of fast heating speed and high temperature uniformity.

[0055] In an embodiment of the present application, because the planar microwave antenna 111 emits microwaves to heat the aerosol generating article 18, and the microwaves reflected by the metal surface will affect the return loss, the support tube 112 of the present embodiment can be a cylindrical structure made of non-metal materials such as quartz, ceramic, or plastic, to avoid the reflection of microwaves emitted by the planar microwave antenna 111 by the metal, thereby ensuring the return loss index.

[0056] In some embodiments, the planar microwave antenna 111 is flexible and rollable, and includes a flexible film and a conductor material carried on the flexible film, the conductor material having certain corrosion resistance and good electrical conductivity, including but not limited to metal materials such as aluminum, copper, tungsten and alloys, for example, the planar microwave antenna 111 can be a flexible printed circuit (FPC). Alternatively, in some other examples, the planar microwave antenna 111 can be a white copper sheet material, and the FPC and the white copper sheet material are soft, so that the planar microwave antenna 111 can be bent to enable the planar microwave antenna 111 to wrap around the support tube 112. In some example embodiments, the heating assembly further includes a positioning component for holding the FPC or the white copper sheet material on the outer surface of the support tube without displacement, for example, commonly used positioning components include heat shrink tubes and high-temperature resistant tapes.

[0057] In one embodiment of the present application, the planar microwave antenna 111 is rolled and attached and fixed to the outer surface of the support tube 112, for example, an FPC antenna. In some alternative embodiments, the conductor material of the planar microwave antenna 111 is integrated on the support tube 112. For example, the planar microwave antenna 111 includes a film layer structure of the conductor material, the film layer structure having a specific pattern shape (see Figure 6 ), and the film layer structure can be combined and integrated on the outer surface of the support tube 112 by means such as but not limited to printing, spraying, etching or vapor deposition.

[0058] In some embodiments, the planar microwave antenna 111 has a Z-shaped or F-shaped structure and is configured in a ring belt shape around the outer periphery of the support tube 112. As an optional example, the planar microwave antenna 111 can be a planar inverted-F antenna (PIFA), and using a PIFA antenna is advantageous for reducing the volume of the heating assembly.

[0059] As Figure 5 With Figure 6As shown, the width and height of the planar microwave antenna 111 after unfolding are matched with the outer diameter and longitudinal length of the support tube 112. In this embodiment, the circumferential width of the planar microwave antenna 111 is smaller than the circumference of the support tube 112, thereby ensuring that the planar microwave antenna 111 can be just attached to the surface of the support tube 112. At the same time, the two sides of the planar microwave antenna 111 along the width direction will not overlap when the planar microwave antenna 111 is arranged around the outer wall of the support tube 112, avoiding the overlapping part from affecting the radiation efficiency of the planar microwave antenna 111. In the height direction, the planar microwave antenna 111 can basically cover or partially cover the longitudinal length of the support tube 112. It can be understood that the height of the planar microwave antenna 111 is matched with the length of the aerosol generating matrix section (e.g., the smoke-generating part 182) in the aerosol generating article 18, so that the radiation area of ​​the antenna can effectively cover the matrix material.

[0060] It is foreseeable that the planar microwave antenna 111 in the form of a ring, with a suitable inner diameter and longitudinal height, is helpful to improve heating efficiency. In a suitable embodiment, the height of the planar microwave antenna 111 along the longitudinal direction of the support tube 112 is 15mm-19mm, and the width of the planar microwave antenna 111 after being unfolded in the circumferential direction is 20mm-29mm. The tubular antenna formed by the roll has a suitable inner diameter, so that the axial center of the aerosol generating matrix in the heating cavity can also have an electric field or magnetic field strength sufficient to volatilize one or more components in the matrix material during operation, which is beneficial to improving the heating uniformity of the aerosol generating matrix.

[0061] like Figure 6 As shown, in one embodiment of this application, the planar microwave antenna 111 is provided with a first through slot 1111 and a second through slot 1112 extending parallel to each other along the circumferential direction or the unfolded width direction, and a portion of the support tube 112 is exposed in the first through slot 1111 and the second through slot 1112. In an optional embodiment of this application, the width L6 of the first through slot 1111 is greater than the width L7 of the second through slot 1112.

[0062] In one embodiment of this application, the planar microwave antenna 111 has opposing first side 1115 and second side 1116 along the circumferential direction, the first side 1115 and the second side 1116 not overlapping to form a gap. Because the two sides of the planar microwave antenna 111 along its length overlap when the planar microwave antenna 111 surrounds the outer wall of the support tube 112, the overlapping portion affects the return loss of the planar microwave antenna 111, resulting in a significant reduction in the energy transmission efficiency radiated by radio frequency. Therefore, as... Figure 5As shown, in this embodiment, the first side 1115 and the second side 1116 of the planar microwave antenna 111 do not overlap and have a gap, ensuring that the planar microwave antenna 111 has high energy transmission efficiency.

[0063] In one embodiment of this application, the planar microwave antenna 111 includes a first portion 1117, a second portion 1118, and a third portion 1119 separated by a first through slot 1115 and a second through slot 1116. The dimensions of the first portion 1117, the second portion 1118, and the third portion 1119 in the direction perpendicular to the first through slot 1111 and the second through slot 1112 are L1, L2, and L3, respectively, where L3 > L1 > L2.

[0064] In one embodiment of this application, the planar microwave antenna 111 is provided with a first through slot 1111 extending from a first side 1115 toward a second side 1116, and the first through slot 1111 and the second side 1116 are spaced apart by a distance L4. In another embodiment of this application, the planar microwave antenna 111 is further provided with a second through slot 1112 extending from the second side 1116 toward the first side 1115, the second through slot 1112 and the first side 1115 are spaced apart by a distance L5, and the second through slot 1112 and the first through slot 1111 are longitudinally offset. In another embodiment of this application, the distance L4 between the first through slot 1111 and the second side 1116 is greater than the distance L5 between the second through slot 1112 and the first side 1115.

[0065] In one embodiment of this application, such as Figure 6 As shown, the planar microwave antenna 111 includes a grounding terminal 1113 and a feeding terminal 1114. The grounding terminal 1113 and the feeding terminal 1114 are located on opposite sides of the opening of the first through slot 1111, respectively. The planar microwave antenna 111 exhibits the strongest electromagnetic wave radiation near the first through slot 1111. See, for example, [reference needed]. Figure 10 The diagram shows the electric field distribution of the heating component when energized. Figure 11 The magnetic field distribution diagram shows that when the grounding terminal 1113 and the feed terminal 1114 are located on either side of the opening of the first through slot 1111, the electric and magnetic field strengths of the planar microwave antenna 111 are highest near the first through slot 1111. As a preferred example, the first through slot 1111 is approximately located at the midpoint of the longitudinal height of the planar microwave antenna 111 (see [reference]). Figure 6)。According to the predetermined length of the aerosol generating substrate, the first through slot 1111 can be designed to be positioned at a specific position of the heating cavity in the longitudinal direction, so that the aerosol generating device can substantially align the middle position of the aerosol generating substrate (smoking portion 182) in the longitudinal direction when the aerosol generating article 18 is inserted into the heating cavity during use, thereby maximizing the absorption of radio frequency energy and facilitating the improvement of the heating speed of the aerosol generating substrate. Or in some alternative embodiments, the ground end 1113 and the feed end 1114 are respectively located on both sides of the opening of the second through slot 1112.

[0066] In an embodiment of the present application, the planar microwave antenna 111 includes a ground end 1113 and a feed end 1114, both of which are located on the first side edge 1115, or both of which are located on the second side edge 1116, that is, both of which are located on the same side edge of the planar microwave antenna 111. Referring to Figure 10 As shown, when the ground end 1113 and the feed end 1114 are both located on the first side edge 1115, the gap region between the first side edge 1115 and the second side edge 1116 also has a high electric field strength.

[0067] Referring to Figure 4 The shell cover 13 is provided with an insertion port 130 which is communicated with the heating cavity 1121, and a part of the aerosol generating article 18 is inserted into the heating cavity 1121 through the insertion port 130, so that the aerosol generating article 18 can be heated by the planar microwave antenna 111 inside the aerosol generating device 1.

[0068] The aerosol generating article 18 includes a filter portion 181 and a smoking portion 182. After the smoking portion 182 of the aerosol generating article 18 is inserted into the heating cavity 1121, since the first through slot 1111 corresponds to the middle position of the smoking portion 182 of the aerosol generating article 18, the middle position of the inserted smoking portion 182 of the aerosol generating article 18 receives the highest heat, and the heat is transmitted to both ends of the smoking portion 182, the energy transmission efficiency is the highest, and the heating effect of the aerosol generating article 18 is the best.

[0069] It should be noted that the aerosol generating device 1 further includes a radio frequency cable which is welded with the planar microwave antenna 111, so that the positive and negative poles of the radio frequency cable are welded with the ground end 1113 and the feed end 1114 respectively, realizing the electrical connection between the radio frequency cable and the planar microwave antenna 111, and the radio frequency cable is used to connect the planar microwave antenna 111 and the circuit board 16. The welding method can be soldering or laser welding.

[0070] In an embodiment of the present application, the ground end 1113 and the feed end 1114 are respectively located at both sides of the opening of the first through slot 1111, and the highest energy radiation area of the planar microwave antenna 111 is concentrated between the ground end 1113 and the feed end 1114 of the first through slot 1111. The positions of the ground end 1113 and the feed end 1114 can be adjusted along the first through slot 1111 according to requirements.

[0071] Due to the influence of the entire material medium of the aerosol generating device 1, the planar design shape of the planar microwave antenna 111, the height of the position of the first through slot 1111, and the length dimension of the first through slot 1111 can all be adjusted to optimize the return loss index of the planar microwave antenna 111. When the middle position of the smoking part 182 of the aerosol generating article 18 corresponds to the highest energy position of the planar microwave antenna 111, the energy transmission efficiency is the highest, and the heating effect on the aerosol generating article 18 is the best.

[0072] In some embodiments, the heating assembly further comprises a temperature sensor, which is attached to the outer surface of the support tube. The temperature sensor can be located at the middle position of the planar microwave antenna 111 in the longitudinal direction; or the temperature sensor is integrated on the planar microwave antenna 111 and has an electrode connection end such as a solder pad for outputting a temperature signal, which can be close to the ground end and the feed end of the planar microwave antenna 111.

[0073] In some embodiments, the aerosol generating device 1 comprises a planar microwave antenna 111 arranged around the outer wall of the support tube 112, which is electrically connected to the circuit board 16. The circuit board 16 is integrated with a microwave generating circuit and a controller connected to the microwave generating circuit. During use, the controller controls the microwave generating circuit to input microwaves of the optimal working frequency into the planar microwave antenna 111, and the planar microwave antenna 111 emits microwaves to radiate the smoking part 182 of the aerosol generating article 18 to generate aerosols through dielectric loss heating. Compared with the existing scheme of winding or electroplating etching a spiral microwave antenna coil on the surface of the support tube, the present application uses a planar microwave antenna 111, which is arranged on the outer surface of the support tube 112, thereby reducing the complexity and cost of the product structure. In addition, since the planar microwave antenna 111 is a planar wire or strip with a certain width, compared with the traditional spiral antenna with linear traces, the planar microwave antenna 111 in the present application can cover most of the outer surface of the support tube 112, thereby providing a larger area of radiation projection in the heating cavity, which is beneficial to improve the microwave heating efficiency of the heating assembly.

[0074] As Figure 7As shown, in some embodiments, the microwave generating circuit includes: an integrated chip, a circulator, a microstrip, a PI-type attenuator, a power detector, and a load. The circulator is mounted outside the heating cavity 61. The output terminal of the integrated chip is connected to the first terminal of the circulator, and the second terminal of the circulator is connected to the planar microwave antenna 111. The microwaves output by the integrated chip are fed into the planar microwave antenna 111 through the first and second terminals of the circulator. The aerosol generating matrix in the heating cavity 61 is heated by the microwaves and releases aerosols. The second terminal of the circulator can also receive the microwave signal fed back from the planar microwave antenna 111 and transmit the fed-back microwave signal through the second terminal of the circulator to the third terminal of the circulator.

[0075] The integrated chip outputs a radio frequency signal with a conduction frequency of f and a power of Pout to the first end of the circulator. The second end of the circulator outputs a radio frequency signal to the planar microwave antenna 111. Since the frequency of the planar microwave antenna 111 will be offset, the planar microwave antenna 111 operates within the offset bandwidth. The return loss of the planar microwave antenna 111 is different at different frequencies. Therefore, some radio frequency signals will be reflected to the third end of the circulator and absorbed by the high-power load.

[0076] As an optional example, the integrated chip is an oscillator power amplifier chip using a single integrated oscillator circuit and a 20-40W unipolar gallium nitride RF power amplifier on a single substrate. The microstrip matching of the gate, drain, and feedback network external to the above integrated chip occupies very little space, which is beneficial for the miniaturization of aerosol generation device products. The power of the unipolar gallium nitride RF power amplifier can also be selected as 20-25W, 25-30W, 30-35W, or 35-40W. In one embodiment of this application, the integrated chip is a GTAH25030C6 chip manufactured by Innogration Technologies.

[0077] like Figure 8 As shown, in some embodiments, the oscillation circuit of the integrated chip is an integrated voltage-controlled oscillator (VCO) and attenuator (ATT), which can adjust the output power. The output power passes sequentially through an integrated first-stage power amplifier, a driver-stage power amplifier, and a final-stage power amplifier; or as shown... Figure 9 As shown, the output power sequentially passes through an integrated first-stage power amplifier + a driver-stage power amplifier, and a final-stage power amplifier. A circulator is a device that transmits radio frequency conducted signals in one direction. In a circulator, the signal conduction direction is from the first terminal to the second terminal, and from the second terminal to the third terminal.

[0078] refer to Figure 7 , Figure 8 or Figure 9As shown, in some possible implementations, the high-power load is selected to work in a high-frequency state, the rated power of the high-power load is greater than the maximum reflected power of the planar microwave antenna 111, and as an optional example, the resistance of the high-power load is 50 ohms or greater, and the high-power load functions to absorb the energy reflected by the planar microwave antenna 111.

[0079] In some embodiments, the microstrip includes a forward output microstrip and a reflection microstrip, two ends of the forward output microstrip are respectively connected to the output end of the integrated chip and the PI attenuator, two ends of the reflection microstrip are respectively connected to the load and the power detector, the forward output microstrip and the reflection microstrip are coupled with a certain coupling degree, the microstrip couples the power of the forward output end and the reflection end, the sampling pin MCU_AD1 of the controller collects the voltage value V 耦合 of the output end through the PI attenuator, and the sampling pin MCU_AD2 collects the voltage value V 反射 of the reflection end through the power detector, so that the magnitudes of the forward output end power and the reflection end power can be calculated, and the return loss value of the planar microwave antenna 111 can be calculated further through the proportional relationship between the forward output end power and the reflection end power.

[0080] In other embodiments, the microstrip includes a reflection microstrip, two ends of the reflection microstrip are respectively connected to the load and the power detector, and the power value of the reflected microwave signal can be mapped through the power detector, and the controller can also actually map the return loss value through the mapping relationship between the changed power value and the return loss.

[0081] In yet other embodiments, the forward output microstrip and the reflection microstrip can be omitted, and the stability of the integrated chip is determined by using the stable current floating change of the integrated chip, an increase in the current indicates that the reflected signal of the microwave antenna is enhanced, resulting in a smaller return loss, and when the current decreases, it indicates that the value of the return loss increases, and the efficiency of microwave heating is improved.

[0082] In some embodiments, the integrated chip works in a frequency range of 2430MHz-2460MHz, and the return loss of the aerosol generating article 18 at each frequency is calculated according to the return loss RL=20log(VSWR+1 / VSWR-1)=20log(P 输出 / P 反射 )=20log(V 耦合 / V 反射 ), where P 输出 and P 反射 correspond to the radio frequency power of the forward output end and the reflected power of the reflection end, V 耦合 and V 反射The corresponding voltage value of the forward output end and the voltage value of the reflection end. For example, as an example, the integrated chip outputs a reference frequency of 2449 MHz, and the radio frequency energy with a power of Pout is input through the first end of the circulator, and is conducted and output to the planar microwave antenna 111 through the second end, and the microwave energy reflected back by the planar microwave antenna 111 is received through the third end and is transferred to the load. In the working process of the aerosol generating device, the heat of the heating assembly is partially transferred to the microwave generating circuit, and as the temperature increases or decreases, the output frequency of the integrated chip increases or decreases, and the maximum is not more than 2460 MHz, and the minimum is not less than 2430 MHz. Therefore, the best return loss of the planar microwave antenna 111 must cover these frequency ranges.

[0083] For example, as an example of some tests, when the return loss is greater than or equal to 10, the power transmission efficiency of the planar microwave antenna 111 is greater than 90%; when the return loss is greater than or equal to 13.7, the power transmission efficiency of the planar microwave antenna 111 is greater than 95.7%; when the return loss is greater than or equal to 18.2, the power transmission efficiency of the planar microwave antenna 111 is greater than 98.5%.

[0084] Through the above tests, it can be known that in the present embodiment, as a suitable example of frequency selection, the heating frequency of the planar microwave antenna 111 is 2430 MHz-2460 MHz, and in this frequency band, the return loss of the planar microwave antenna 111 is greater than or equal to 10, the transmission efficiency of the planar microwave antenna 111 is greater than 90%, and the heating effect on the aerosol generating article 18 is better.

[0085] The output end of the existing integrated chip is not provided with a circulator, and is directly connected to the planar microwave antenna 111. When the return loss of the planar microwave antenna 111 deteriorates, the microwaves will be reflected back to the output end of the integrated chip, causing self-excitation and damaging the integrated chip. Therefore, the present embodiment increases a circulator at the output end of the integrated chip, so that the microwaves reflected back by the planar microwave antenna 111 are absorbed by the load, thereby protecting the integrated chip.

[0086] In some other embodiments of the present application, the integrated chip selects the best working frequency point in the first 5 frequency points with the best transmission efficiency as the actual microwave heating frequency point, and the heating control method is as follows: the controller controls the integrated chip to output a microwave signal with a frequency of f and a power of Pout; the microwave signal is input through the first end of the circulator, and is conducted and output to the planar microwave antenna through the second end; the planar microwave antenna reflects part of the microwave signal to the third end of the circulator; the power of the first end and the third end of the circulator is coupled through the PI type attenuator and the power detector respectively, and V 耦合 and V 反射 are output to the controller; the controller calculates the return loss RL=20log(VSWR+1 / VSWR-1)=20log(P 输出 / P 反射 ) = 20 log(V 耦合 / V 反射 ) calculate the return loss of the output frequency; the controller increases or decreases the output frequency of the integrated chip according to the preset adjustment value, repeatedly executes the above steps until the output frequency of the integrated chip traverses 2430MHz-2460MHz, and obtains return loss values of multiple output frequencies; the controller selects the output frequency corresponding to the return loss greater than 10, and records the output frequency with the return loss greater than 10 and its corresponding transmission efficiency in the array to form a mapping relationship; the controller selects the first five output frequencies with the best transmission efficiency from the array, and selects the best output frequency from the five output frequencies as the actual output frequency of the integrated chip. By controlling the aerosol generating device 1 by the above heating control method, the first five output frequencies with the best transmission efficiency can be selected, and the best output frequency can be selected as the actual output frequency of the integrated chip, so that the planar microwave antenna 111 heats the aerosol generating article 18 at the best output frequency when the transmission efficiency is greater than 90%, and the heating efficiency is improved. It should be noted that the preset adjustment value can be set by the controller as needed, and in this embodiment, the preset adjustment value can be set to 2MHz.

[0087] It can be understood that the aerosol generating device 1 can output microwave signals with a fixed frequency during heating use. For example, in some example embodiments, the best frequency point of the microwave antenna can shift during long-term use of the device, so the above program for screening the best output frequency is built into the controller in the microwave generating circuit. When the aerosol generating device 1 is started each time or periodically, the integrated chip calls and runs the program to determine the best output frequency by the above method, and then uses the best output frequency to feed radio frequency energy through the microwave antenna to control the heating assembly to start working. For example, in other example embodiments, the aerosol generating device 1 can use the above method to determine the best output frequency only during the debugging stage before leaving the factory, and use the determined best output frequency to heat during actual use of the aerosol generating device 1.

[0088] In other example embodiments, the aerosol generating device 1 can output microwave signals with variable frequencies during heating use. For example, due to factors such as temperature changes, the frequency of the microwave antenna can shift, so the controller in the microwave generating circuit is configured to collect feedback signal parameters of the microwave antenna in real time or periodically and calculate return loss values, so as to adjust the best output frequency output to the microwave antenna according to the change of the return loss values.

[0089] The above merely describes preferred embodiments of the present application, and is not intended to limit the technical scope of the present application in any way. Any minor modification, equivalent change and modification made to the above embodiments according to the technical essence of the present application shall still fall within the technical scope of the present application.

Claims

1. An aerosol generating device, characterized in that, include: The support tube defines a heating chamber for accommodating at least a portion of an aerosol-generating article comprising an aerosol-forming matrix; A microwave antenna is provided for transmitting radio frequency energy when energized and conducting it to the heating cavity, thereby heating the aerosol-forming matrix in the aerosol-generating article within the heating cavity to generate aerosols. A microwave generating circuit is connected to the microwave antenna; A controller, connected to the microwave generating circuit, is configured to control the microwave generating circuit to feed radio frequency signals to the microwave antenna, thereby causing the microwave antenna to emit microwaves to radiate and heat the aerosol-generated product within the heating cavity.

2. The aerosol generating apparatus according to claim 1, characterized in that, The microwave generating circuit includes: An integrated chip, connected to the controller, is used to output radio frequency signals; A circulator is installed outside the heating cavity. The first end of the circulator is connected to the output terminal of the integrated chip, and the second end of the circulator is connected to the microwave antenna, so that the radio frequency signal output by the integrated chip is fed into the microwave antenna through the first and second ends of the circulator. The load, connected to the third end of the circulator, is configured to absorb at least a portion of the microwaves reflected from the microwave antenna reaching the load via the second and third ends of the circulator.

3. The aerosol generating apparatus according to claim 2, characterized in that, The integrated chip includes: The substrate has a gate negative voltage terminal and a drain voltage terminal, and the substrate integrates an oscillation circuit and a unipolar gallium nitride RF power amplifier. A microstrip feedback network is connected between the negative gate voltage terminal and the drain voltage terminal.

4. The aerosol generating apparatus according to claim 3, characterized in that, The power of the unipolar gallium nitride RF power amplifier is 20-40W.

5. The aerosol generating apparatus according to claim 1, characterized in that, The microwave generating circuit includes: A voltage-controlled oscillator is configured to generate radio frequency signals; A first-stage power amplifier, a driver-stage power amplifier, and a final-stage power amplifier, connected in series, are connected to the voltage-controlled oscillator and configured to output the amplified radio frequency signal; the first-stage power amplifier and the driver-stage power amplifier are integrated, or the driver-stage power amplifier and the final-stage power amplifier are integrated.

6. The aerosol generating apparatus according to claim 5, characterized in that, The voltage-controlled oscillator and attenuator are integrated into an oscillation circuit.

7. The aerosol generating apparatus according to claim 2, characterized in that, The rated power of the load is greater than the maximum reflected power of the microwave antenna.

8. The aerosol generating apparatus according to claim 2, characterized in that, The resistance of the load is greater than or equal to 50Ω.

9. The aerosol generating apparatus according to any one of claims 2-8, characterized in that, The microwave generating circuit also includes: Microstrip, including forward output microstrip and reflective microstrip; A PI-type attenuator is provided, wherein the two ends of the positive output microstrip are respectively connected to the output terminal of the integrated chip and the PI-type attenuator, the PI-type attenuator is also connected to the controller, and the controller is further configured to detect the output voltage value of the integrated chip through the PI-type attenuator; A power detector is provided, with the load and the power detector connected to the two ends of the reflective microstrip respectively. The controller is also configured to detect the voltage value at the reflective end of the load through the power detector, and to calculate the return loss value of the microwave antenna based on the output voltage value and the voltage value at the reflective end.

10. The aerosol generating apparatus according to any one of claims 2-8, characterized in that, The microwave generating circuit also includes: Microstrips, including reflective microstrips; A power detector is provided, with the load and the power detector connected to its two ends respectively. The controller is also configured to detect the voltage value at the reflecting end of the load through the power detector and to calculate the return loss value of the microwave antenna based on the voltage value at the reflecting end.

11. The aerosol generating apparatus according to claim 9, characterized in that, The controller is also configured to control the integrated chip to operate in a frequency range of 2430MHz-2460MHz, and to calculate the return loss value of the aerosol-generated product at each frequency based on the output voltage value and the reflection voltage value.

12. The aerosol generating apparatus according to claim 11, characterized in that, The controller is also configured to determine the optimal operating frequency based on the return loss value at each frequency, and to control the integrated chip to output radio frequency signals according to the optimal operating frequency.

13. The aerosol generating apparatus according to claim 1, characterized in that, The microwave antenna is a planar microwave antenna, which is constructed as a thin sheet or a film structure and is at least partially disposed around the outer surface of the support tube.

14. The aerosol generating apparatus according to claim 1, characterized in that, The aerosol generating device also includes a power supply unit for providing power to the microwave generating circuit and the controller.

15. The aerosol generating apparatus according to claim 1, characterized in that, The aerosol generating device also includes a button configured to control the microwave antenna to start or stop emitting microwaves.

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