Aerosol generation device and heating system for it

Description

FIELD

[0001] The present invention relates to cigarette substitutes, and more particularly to an aerosol generating device and a heating assembly thereof.BACKGROUND

[0002] Conventionally, a mounting base of a heating assembly is usually sleeved on an area of a heating member where electrodes located. Therefore, the electrodes are located adjacent to and electrically connected to a heat generating resistance portion, heat generated by the heat generating resistance portion when the heat generating resistance portion is powered will be easily transferred to the mounting base, thereby it will cause heat loss and reduce atomization effect. Meanwhile, the mounting base may dissipate harmful gases when heated to a high temperature, which may affect user's health.

[0003] Publication CN 107 373 776 A discloses an electric heating element for heating non-burning cigarettes. The electric heating element comprises two layers of thin ceramic wafers and an electric heating sheet that is arranged between the ceramic wafers. The electric heating sheet is connected with conducting elec-trodes that are also located between the ceramic wafers, and the conducting electrodes are connected with an external circuit through round holes that are arranged in the surfaces of the ceramic wafers. The bottoms of the ceramic wafers are provided with grooves that communicate with the interiors of the ceramic wafers, wherein a certain distance is kept between the grooves and the electric heating sheet. Temperature measuring elements can be arranged in the grooves to precisely measure the temperature of the electric heating sheet. Further heating assemblies for an aerosol generating system are disclosed in publications CN 205 757 216 U, WO 2014 / 102092 A1, WO 2016 / 124552 A1 and EP 2 921 065 A1.SUMMARY

[0004] The technical problem to be solved by the present invention is to provide an improved baked smoking device and a heating assembly thereof.

[0005] The technical solution adopted by the present invention to solve the technical problem is to provide a heating assembly for an aerosol generating device, which includes a heating member including a sheet-like substrate and an electric conductive path arranged on an outer side of the sheet-like substrate.

[0006] The electric conductive path includes a heat generating resistance portion, and an electrical connection portion electrically connected to the heat generating resistance portion.

[0007] The heat generating resistance portion and the electrical connection portion are arranged along a length direction of the sheet-like substrate. The electrical connection portion comprises two conductive electrodes that are electrically connected to the heat generating resistance portion.

[0008] The heating assembly further includes a mounting base.

[0009] The mounting base is sleeved on the heating member, and located between an end portion of the heating member where the electrical connection portion is located and the two conductive electrodes.

[0010] Further, a lengthwise section of the sheet-like substrate where the conductive electrodes are located is provided with through holes.

[0011] Preferably, the electrical connection portion includes two lead wires, wherein each lead wire is electrically connected to a corresponding conductive electrode and is led out from an end of the heating member away from the heat generating resistance portion along the length direction of the heating member.

[0012] Preferably, the conductive electrode is formed by printing and then sintering silver slurry.

[0013] Preferably, the lead wire is connected to the conductive electrode by a high-temperature brazing process with silver-copper solder, pure silver solder or nickel solder under a protective atmosphere at 600-1100°C.

[0014] Alternatively, the lead wire is connected to the conductive electrode by a soldering process with high-temperature solder paste.

[0015] Preferably, the sheet-like substrate is made of metal or alloy material, the heating member further includes an insulation layer covering the sheet-like substrate, and the electric conductive path is provided outside the insulation layer.

[0016] Preferably, the sheet-like substrate has a thickness of 0.2-0.8 mm, and the insulation layer has a thickness less than 0.1 mm.

[0017] Preferably, the insulation layer is formed by sintering after a surface of the sheet-like substrate is covered with glass slurry comprising silicon oxide, calcium oxide, and aluminum oxide.

[0018] Preferably, the insulation layer is formed on the sheet-like substrate by spraying or printing; and the electric conductive path is provided on the insulation layer on one side, and two sides of the sheet-like substrate are covered with the insulation layers respectively.

[0019] Preferably, an end of the heating member away from the mounting base is provided with a sharp head facilitating an insertion of a cigarette into a tube.

[0020] Preferably, the sheet-like substrate is made of stainless steel or titanium alloy and formed by stamping or wire cutting process.

[0021] Preferably, the heat generating resistance portion is formed by printing and then sintering silver-palladium resistor slurry, ruthenium-palladium resistor slurry, platinum slurry, or nickel-based slurry.

[0022] Preferably, the heating member further includes an isolation layer covering the electric conductive path,

[0023] The isolation layer is a glaze layer formed by sintering glass glaze material, and all outer surfaces of the heating member are covered with the isolation layer.

[0024] Preferably, the mounting base is injection-molded from high molecular polymer.

[0025] An aerosol generating device includes said heating assembly.

[0026] The implementation of the baked smoking device and its heating assembly according to the present invention provides the following advantages: since there is no heating zone between the second end where the mounting base is located and the conductive electrode, the possibility of generating harmful gases is reduced, therefore there can be more choices for the material of the mounting base and thus the cost is reduced. Further, in the heating member, a larger temperature gradient is formed between the section corresponding to the heat generating resistance portion inserted into the tobacco and the section corresponding to the conductive electrode, and the section corresponding to the conductive electrode has relatively low temperature and small heat dissipation, which is beneficial to effective use of energy.BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The present invention will be further described below in conjunction with the accompanying drawings and embodiments, in which: Fig. 1 is a schematic cross-sectional view of an aerosol generating device according to one embodiment of the present invention, with a heating member inserted into a tube having cigarette therein; Fig. 2 is a schematic view of a heating assembly according to the present invention; Fig. 3 is a schematic cross-sectional view of the heating member in Fig. 1; Fig. 4 is an exploded schematic view showing each layer of a heating assembly according to the present invention; Fig. 5 is a temperature field distribution diagram of heating cigarette when the sheet-like substrate is made of metal; Fig. 6 is a schematic view of the heating member in Fig. 2 with the heating member having a gradually changed width; and Fig. 7 is a temperature field distribution diagram of heating cigarette when the heating member is made of zirconium oxide. DESCRIPTION OF THE EMBODIMENTS

[0028] In order to provide a better understanding of the technical features, objectives and effects of the present invention, particular embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0029] As shown in Fig. 1 and Fig. 2, an aerosol generating device according to a preferred embodiment of the present invention includes a tubular tube 1 and a heating assembly 2. The heating assembly 2 includes a heating member 21, a lead wire 22 and a mounting base 23.

[0030] As shown in Figs. 1 to 3, the heating member 21 has a sheet-like shape and is configured to inserted into the tube 1 in a detachable manner. The heating member 21 includes two lengthwise opposite ends, i.e., a first end A and a second end B. The first end A extends outwards, by which the heating member 21 may be inserted into the tube 1 of the baked smoking device.

[0031] The heating member 21 includes two widthwise opposite sides, i.e., a first side C and a second side D. The first side C and the second side D are respectively provided with blade portions 211 that make the thickness of the heating member 21 gradually decrease toward edges in the width direction. A central line of the heating member 21 is located in the center of the tube 1, and distances from two widthwise opposite sides of the heating member 21 to an inner wall of the tube 1 are equivalent to each other.

[0032] The two widthwise opposite sides of the heating member 21 are gradually thinned, such that when the heating member 21 is inserted into a cigarette 3, pressure applied on tobacco of the cigarette 3 by the two widthwise opposite sides of the heating member 21 can be reduced, and thus the tobacco proximal to the two widthwise opposite sides corresponding to the blade portions 211 will not be subjected to extrusion or compression, thereby relieving the pressure applied on the tobacco proximal to the two sides and improving tobacco atomization efficiency. The blade portion 211 may provide a smooth transition to prevent the tobacco from adhering on the side surfaces of the heating sheet.

[0033] The heating member 21 includes two opposite surfaces, i.e., a first surface E and a second surface F in a thickness direction. The blade portion 211 includes chamfers provided on edges of the first surface E and the second surface F adjacent to the first side C, and chamfers provided on edges of the first surface E and the second surface F adjacent to the second side D.

[0034] The chamfer may be bevel or rounded. The edges of the surface E and the second surface F adjacent to the first side C are respectively provided with the chamfers, and the edges of the first surface E and the second surface F adjacent to the second side D are respectively provided with the chamfers. The blade portions 211 of the first side C and the second side D make the first side C and the second side D of the heating member 21 have rounded or sharp edges.

[0035] In other embodiments, the blade portion 211 may alternatively be chamfered only on the edge of the first surface E or the second surface F adjacent to the first side C, and only on the edge of the first surface E or the second surface E adjacent to the second side D, thus making the first side C and the second side D have sharp edges, thereby facilitating formation of substrate by one-time stamping.

[0036] The blade portions 211 on the two opposite sides have smooth transitions, or are polished smoothly, or glazed, which can effectively prevent the tobacco from adhering on the sides and relieve tobacco accumulation.

[0037] As shown in Fig. 4, the heating member 21 includes a sheet-like substrate 212 made of metal, an insulation layer 213 covering the sheet-like substrate 212, and an electric conductive path 214 arranged outside the insulation layer 213. A lead wire 22 is connected to the electric conductive path 214 and is led out. When the lead wire 22 and thus the electric conductive path 214 are energized, the electric conductive path 214 heats up to atomize the tobacco.

[0038] Preferably, the substrate of the heating member 21 is made of metal or alloy material, and the sheet-like substrate 212 may be made of general metal materials such as stainless steel or titanium alloy, preferably stainless steel, such as grade 430 or grade 304 stainless steel. The sheet-like substrate 212 usually has a thickness of about 0.2-0.8 mm, and is formed by stamping or wire cutting process, so as to save cost. The blade portion 211 of the metal sheet-like substrate 212 may be formed by stamping, so as to further save cost. Length, width and other dimensions of the heating member 21 match with diameter and length of the cigarettes to be used with it, which facilitates sufficient heating of the tobacco.

[0039] The metal sheet-like substrate 212 is used as a main body of the heating member 21 so as to provide high ductility, which effectively prevents the heating member 21 from breaking under long-term high temperature and mechanical impacts such as when loading cigarettes. Meanwhile, the metal sheet-like substrate 212 has good thermal conductivity, which ensures surface temperature uniformity of the heating sheet, and facilitates heating the non-combustible cigarette to obtain an optimized taste.

[0040] As shown in Figs. 5 and 7, according to steady-state simulation experiments, under a same temperature field, the area exceeding 215 degrees Celsius around the heating sheet made of stainless steel is larger than that around the heating sheet made of ceramic such as zirconium oxide and the like, thus the heating sheet made of stainless steel can obtain higher atomization efficiency and better taste.

[0041] Preferably, the first end A of the sheet-like substrate 212 is provided with a sharp head 215 that facilitates the insertion of the cigarette 3, and the sharp head 215 can guide the insertion of the heating member 21 to reduce insertion resistance.

[0042] In order to meet process requirements for printing the electric conductive path 214 on the sheet-like substrate 212, the sheet-like substrate 212 includes a flat surface 2121 located between the blade portions 211 formed on the two opposite sides of the heating sheet, and the electric conductive path 214 is printed in an area of the flat surface 2121. The blade portions 211 are arranged outward from two widthwise opposite sides of the flat surface 2121.

[0043] The insulation layer 213 is formed by covering a surface of the sheet-like substrate 212 with glass slurry containing silicon oxide, calcium oxide, and aluminum oxide and then sintering it at 400-1000°C. Since the sheet-like substrate 212 made of metal or alloy is conductive, the insulation layer 213 can prevent short circuit between the sheet-like substrate 212 and the electric conductive path 214.

[0044] The insulation layer 213 is formed on the sheet substrate 212 by spraying or printing. The thickness of the insulation layer 213 may be designed according to withstand voltage requirements between the electric conductive path 214 and the sheet-like substrate 212. Generally, the insulation layer 213 has a thickness less than 0.1 mm.

[0045] In order to prevent the metal sheet-like substrate 212 from being oxidized during high-temperature use, preferably, two sides of the sheet-like substrate 212 are covered with insulation layers 213. The electric conductive path 214 is provided on the insulation layer 213 on one side. The insulation layer 213 may alternatively be provided only at one side of the sheet-like substrate 212 for arranging the electric conductive path 214. When the substrate of the heating member 21 is made of a non-metallic and non-conductive material, the insulation layer 213 may alternatively be eliminated.

[0046] The electric conductive path 214 is used as a resistance heater, and may be a conductive layer formed on the insulation layer 213 by physical-vapor-depositing, electroplating, or printing.

[0047] Preferably, the electric conductive path 214 includes a heat generating resistance portion 2141 and an electrical connection portion electrically connected to the heat generating resistance portion 2141. The heat generating resistance portion 2141 and the electrical connection portion are arranged along the length direction of the sheet-like substrate 212, and the conductive electrodes 2142 are connected to an external circuit. Preferably, the electrical connection portion includes two conductive electrodes 2142 electrically connected to the heat generating resistance portion 2141.

[0048] The lead wires 22 are connected to the conductive electrodes 2142, and are led out from one end away from the heat generating resistance portion 2141 along the length direction of the heating member 21. That is, the heat generating resistance portion 2141 and the conductive electrodes 2142 are arranged from the first end A to the second end B, and the lead wires 22 are led out from the second end B.

[0049] The heat generating resistance portion 2141 may be formed by printing and then sintering any one of silver-palladium resistor slurry, ruthenium-palladium resistor slurry, platinum slurry, and nickel-based slurry. The heat generating resistance portion 2141 can be flexibly patterned, and combined with the characteristics of the slurry and the thickness of the heat generating resistance portion 2141, a suitable resistance value for the heating member 21 can be obtained. The resistance value of the heating member 21 is generally between 0.3-2.0Ω, and the thickness of the resistor 2141 is generally less than 0.1 mm, preferably less than 20 um. The conductive electrode 2142 is formed by printing and then sintering the silver-based slurry with relatively low resistivity.

[0050] When the lead wire 22 is connected to an external power source, the heat generating resistance portion 2141 can be energized to generate heat. The lead wire 22 may be connected to the conductive electrodes 2142 by a high-temperature brazing process with silver-copper solder, pure silver solder or nickel solder under a protective atmosphere of 600-1100°C. The lead wire 22 is connected to the conductive electrode 2142 by a soldering process with high temperature solder paste, where the operating temperature is greater than 300°C.

[0051] Since the metal sheet-like substrate 2121 has good thermal conductivity, in order to prevent the heat loss, a lengthwise section of the sheet-like substrate 212 where the conductive electrode 2142 is located is provided with through holes 2122. The through holes 2122 can isolate heat and reduce heat transferred to the second end B.

[0052] Since the section corresponding to the conductive electrode 2142 has a relatively low temperature such that the tobacco cannot be fully atomized, the tobacco located at that section may store and absorb a certain amount of tobacco tar, thereby preventing or reducing the leakage of tobacco tar therefrom.

[0053] In the heating member 21, the section corresponding to the heat generating resistance portion 2141 inserted into the tobacco and the section corresponding to the conductive electrode 2142 have a large temperature gradient therebetween. The section corresponding to the conductive electrodes 2142 has a relatively low temperature and thus has low heat dissipation, which is beneficial to effective use of energy.

[0054] In order to isolate the heat generating resistance portion 2141 from the outside air and further improve its service life and stability, the heating member 21 further includes an isolation layer 216 covering the electric conductive path 214.

[0055] The isolation layer 216 is a glaze layer formed by sintering glass glaze material and has a thickness generally less than 0.1 mm. Two sides of the sheet-like substrate 212 are covered with the isolation layers 216 respectively. By providing the glaze layer, the surface of the heating sheet is smooth and has a smaller roughness, thereby reducing adhesion of tobacco stains and tobacco tar generated after baking of tobacco, and facilitating cleaning the appliance. In other embodiments, the isolation layer 216 may only cover the side where the electric conductive path 214 is located.

[0056] Preferably, as shown in Fig. 6, in order to facilitate the insertion of the heating member 21 into the cigarette 3, the width of the heating member 21 is gradually increased from the first end A to the second end B of the heating member 21, so that the heating member 21 has a shape of a sword. The narrow first end A in combination with the thinning structure of the blade portion 211, makes a relatively small insertion resistance applied on the heating member 21, which is beneficial to the insertion and can effectively reduce the accumulation of tobacco on the sides of the heating sheet. The wider bottom of the heating member is beneficial to increase the strength of the heating sheet so as to prevent the heating member from breaking due to multiple times of insertion and removal of cigarettes.

[0057] Generally, an angle between two widthwise opposite sides of the sharp head 215 is greater than an angle between two widthwise opposite sides of the second end B of the heating member 21. In other embodiments, the heating member 21 may alternatively be triangular in shape.

[0058] Referring to Fig. 2 again, the mounting base 23 is sleeved on the second end B of the heating member 21, i.e. sleeved on the end of the heating member 21 from which the lead 22 is led out, and sleeved onto the electrical connection portion. In other embodiments, the mounting base 23 may alternatively be an individual component separately mounted on the heating member 21.

[0059] The sharp head 215 is located at the end of the heating member 21 away from the mounting base 23, such that the mounting base 23 and the sharp head 215 are respectively located at two opposite ends of the heating member 21. When one end of the heating member 21 corresponding to the sharp head 215 is inserted into the tube 1, the mounting base 23 will abut against an outer end of the tube 1 to limit the insertion depth of the heating member 21.

[0060] Since the lengthwise section of the sheet-like substrate 212 where the conductive electrode 2142 is located is provided with the through holes 2122, the heat transfer to the second end B is reduced, thereby preventing the temperature of the mounting base 23 from becoming too high.

[0061] Since there is no heating zone between an end portion of the second end B where the mounting base 23 is located and the conductive electrode 2142, the possibility of generating harmful gas is reduced, and there can be more choices for the material of the mounting base 23, so that the cost can be reduced. Usually, the mounting base is injection-molded from high molecular polymer, such as polyether ether ketone and high temperature nylon and the like.

Claims

1. A heating assembly (2) for an aerosol generating device, comprising a heating member (21) which comprises a sheet-like substrate (212) and an electric conductive path (214) arranged on the sheet-like substrate (212); wherein the electric conductive path (214) comprises a heat generating resistance portion (2141) and an electrical connection portion electrically connected to the heat generating resistance portion (2141); wherein the heat generating resistance portion (2141) and the electrical connection portion are arranged along a length direction of the sheet-like substrate (212); wherein the electrical connection portion comprises two conductive electrodes (2142) that are electrically connected to the heat generating resistance portion (2141); wherein the heating assembly (2) further comprises a mounting base (23), and the mounting base (23) is sleeved on the heating member (21); characterised in that the mounting base (23) is located between an end portion of the heating member (21) where the electrical connection portion is located and the two conductive electrodes (2142); and in that a lengthwise section of the sheet-like substrate (212) where the conductive electrodes (2142) are located is provided with through holes (2122).

2. The heating assembly (2) according to claim 1, characterized in that the electrical connection portion comprises two lead wires (22), wherein each lead wire (22) is electrically connected to a corresponding conductive electrode (2142), and the lead wire (22) is led out from an end of the heating member (21) away from the heat generating resistance portion (2141) along the length direction of the heating member (21).

3. The heating assembly (2) according to claim 1, characterized in that the conductive electrodes (2142) are formed by printing and then sintering silver slurry.

4. The heating assembly (2) according to claim 2, characterized in that the lead wire (22) is connected to the conductive electrode (2142) by a high-temperature brazing process with silver copper solder, pure silver solder or nickel solder under a protective atmosphere of 600-1100°C; or, the lead wire (22) is connected to the conductive electrode (2142) by a soldering process.

5. The heating assembly (2) according to claim 1, characterized in that the sheet-like substrate (212) is made of metal or alloy material, and the heating member (21) further comprises an insulation layer (213) covering the sheet-like substrate (212), and the electric conductive path (214) is arranged outside the insulation layer (213).

6. The heating assembly (2) according to claim 5, characterized in that the sheet-like substrate (212) has a thickness less than 0.2-0.8 mm, and the insulation layer (213) has a thickness less than 0.1 mm.

7. The heating assembly (2) according to claim 5, characterized in that the insulation layer (213) is formed by sintering after a surface of the sheet-like substrate (212) is covered with glass slurry comprising silicon oxide, calcium oxide, and aluminum oxide.

8. The heating assembly (2) according to claim 5, characterized in that the insulation layer (213) is formed on the sheet-like substrate (212) by spraying or printing; and the electric conductive path (214) is provided on the insulation layer (213) on one side, and two sides of the sheet-like substrate (212) are covered with the insulation layers (213) respectively.

9. The heating assembly (2) according to claim 1, characterized in that an end of the heating member (21) away from the mounting base (23) is provided with a sharp head (215) to facilitate insertion of cigarette (3) .

10. The heating assembly (2) according to any one of claims 1 to 9, characterized in that the sheet-like substrate (212) is made of stainless steel or titanium alloy and is formed by stamping or wire cutting process.

11. The heating assembly (2) according to any one of claims 1 to 9, characterized in that the heat generating resistance portion (2141) is formed by printing and then sintering silver-palladium resistance slurry, ruthenium-palladium resistance slurry, platinum slurry, or nickel-based slurry.

12. The heating assembly (2) according to any one of claims 1 to 9, characterized in that the heating member (21) further comprises an isolation layer (216) covering the electric conductive path (214), and wherein the isolation layer (216) is a glaze layer formed by sintering a glass glaze material, and each outer surface of the heating member (21) is covered with the isolation layer (216).

13. The heating assembly (2) according to claim 1, characterized in that the mounting base (23) is injection-molded from high molecular polymer.

14. An aerosol generating device, characterized by comprising the heating assembly according to any one of claims 1 to 13.