EP4613130A1

EP4613130A1 - Aerosol generating device, heater for aerosol generating device and preparation method

Info

Publication number: EP4613130A1
Application number: EP23893622.3A
Authority: EP
Inventors: Guimin Chen; Zuqiang QI; Jiamao LUO; Baoling LEI; Zhongli XU; Yonghai LI
Original assignee: Shenzhen FirstUnion Technology Co Ltd
Current assignee: Shenzhen FirstUnion Technology Co Ltd
Priority date: 2022-11-24
Filing date: 2023-11-06
Publication date: 2025-09-10
Also published as: KR20250114060A; EP4613130A4; JP2025536811A; CN118058529A; WO2024109531A1

Abstract

This application proposes an aerosol generating device, and a heater for an aerosol generating device and a preparation method therefor. The aerosol generating device includes: a chamber for receiving an aerosol generating product; an electrically-insulating substrate configured as a tubular shape surrounding or defining the chamber; and a heating element bonded to the substrate and surrounding at least a portion of the substrate. The substrate and the heating element are thermally conductive with each other. During use, the substrate can generate heat by receiving heat from the heating element, which in turn heats the aerosol generating product. The substrate includes at least one of a ceramic, glass, and quartz, and the tube wall thickness of the substrate is less than 0.2 mm. The above aerosol generating device uses an ultra-thin substrate which has a tube wall thickness less than 0.2 mm, and the ultra-thin substrate is more sensitive to temperature rising or lowering during a heating process and is beneficial for reducing energy consumption.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to Chinese Patent Application No. 202211480500.0, filed with the China National Intellectual Property Administration on November 24, 2022 and entitled "AEROSOL GENERATING DEVICE, AND HEATER FOR AEROSOL GENERATING DEVICE AND PREPARATION METHOD THEREFOR", which is incorporated herein by reference in its entirety.

TECHNICAL FIELD

Embodiments of the present invention relate to the field of heat-not-burn aerosol generating technologies, and in particular, to an aerosol generating device, and a heater for an aerosol generating device and a preparation method therefor.

BACKGROUND

During use of tobacco products (such as cigarettes and cigars), tobacco is burned to produce tobacco smoke. Attempts are made to replace these tobacco-burning products by making products that release compounds without burning.
An example of such products is a heating device, which releases compounds by heating rather than burning a material. For example, the material may be an aerosol generating product including tobacco or other non-tobacco products. These non-tobacco products may or may not include nicotine. In a known heating device, a heater with a ceramic substrate is used to heat a tobacco-containing product or other non-tobacco products. The heater with a ceramic substrate is manufactured with a ceramic tube as a substrate base material by printing a resistance heating track on the ceramic tube.

SUMMARY

An embodiment of this application provides an aerosol generating device, configured to heat an aerosol generating product to generate an aerosol, including:

a chamber for receiving the aerosol generating product;
an electrically-insulating substrate configured as a tubular shape surrounding or defining the chamber; and
a heating element bonded to the substrate and surrounding at least a portion of the substrate, where
the substrate and the heating element are thermally conductive with each other; during use, the substrate can generate heat by receiving heat from the heating element, which in turn heats the aerosol generating product; and
the substrate includes at least one of a ceramic, glass, and quartz, and a tube wall thickness of the substrate is less than 0.2 mm.

In some implementations, the substrate includes no elemental metal.
In some implementations, the tube wall thickness of the substrate ranges from 0.1 mm to 0.2 mm.
In some implementations, the substrate is formed by cylindrical grinding of a tubular precursor on a cylindrical grinding machine to thin a tube wall.
In some implementations, testing is performed according to a three-point bending strength test method, and bending strengths of all test sites of the substrate are greater than 40 N.
In some implementations, the heating element includes a heating layer formed on or bonded to the substrate.
In some implementations, the heating layer is configured in an annular shape around the substrate.
In some implementations, the substrate includes a first end and a second end that face away from each other in a longitudinal direction;

a first electrode bonded to the substrate and arranged close to the first end; and
a second electrode bonded to the substrate and arranged close to the second end; and
the heating layer is configured to extend between the first electrode and the second electrode, and a current is guided by the first electrode and the second electrode in a longitudinal direction of the heating layer.

In some implementations, when a current is guided in a longitudinal direction of a heating layer by a first electrode and a second electrode, resistance of the heating layer ranges from 0.5 Ω to 3 Ω.
In some implementations, when the heating element performs heating at a power supply of 30 W, the substrate is configured to be heated from room temperature to 320°C within 30s.
Another embodiment of this application further provides a heater for an aerosol generating device, including:

an electrically-insulating substrate configured to be tubular; and
a heating element bonded to the substrate and surrounding at least a portion of the substrate, where
the substrate and the heating element are thermally conductive with each other; during use, the substrate can generate heat by receiving heat from the heating element; and the substrate includes at least one of a ceramic, glass, and quartz, and the substrate has a tube wall thickness less than 0.2 mm.

Another embodiment of this application further provides a heater for an aerosol generating device, including:

a quartz tube; and
an infrared radiation coating formed on the quartz tube and surrounding at least a portion of the quartz tube, to radiate infrared rays into a tubular hollow of the quartz tube,
where the quartz tube has a tube wall thickness less than 0.2 mm.

Another embodiment of this application further provides a preparation method for a heater for an aerosol generating device, including:

obtaining a tubular precursor, where the precursor includes at least one of a ceramic, glass, and quartz, and the precursor has a tube wall thickness greater than 0.2 mm;
grinding the precursor on a cylindrical grinding machine until the tube wall thickness is less than 0.2 mm, to obtain an electrically-insulating substrate; and
forming a heating element on the substrate.

The above aerosol generating device uses an ultra-thin substrate which has a tube wall thickness less than 0.2 mm, and the ultra-thin substrate is more sensitive to temperature rising or lowering during a heating process and is beneficial for reducing energy consumption.

BRIEF DESCRIPTION OF THE DRAWINGS

One or more embodiments are exemplarily described with reference to corresponding accompanying drawings, and the exemplary descriptions are not intended to limit the embodiments. Elements in the accompanying drawings that have same reference numerals are represented as similar elements, and unless otherwise particularly stated, the figures in the accompanying drawings are not drawn to scale.

FIG. 1 is a schematic diagram of an aerosol generating device according to an embodiment;
FIG. 2 is a schematic structural diagram of a heater in FIG. 1 according to an embodiment;
FIG. 3 is a schematic exploded view of the heater in FIG. 2 from a perspective;
FIG. 4 is a temperature field distribution diagram of the heater in FIG. 2 during heating;
FIG. 5 is a schematic structural diagram of the heater in FIG. 1 according to another embodiment;
FIG. 6 is a schematic diagram of a thinning process of a substrate according to an embodiment;
FIG. 7 is a schematic diagram of a thinning process of a substrate according to another embodiment;
FIG. 8 is a comparison diagram of a heating rate before and after a substrate is thinned by cylindrical grinding according to an embodiment;
FIG. 9 is a schematic diagram of a heating curve of an aerosol generating product according to an embodiment; and
FIG. 10 is a schematic diagram of a preparation of a heater according to another embodiment.

DETAILED DESCRIPTION

For ease of understanding of this application, this application is described below in more detail with reference to accompanying drawings and specific implementations.
An embodiment of this application provides an aerosol generating device 100 for heating instead of burning an aerosol generating product 1000, such as cigarettes, to evaporate or release at least one component of the aerosol generating product 1000 to form an aerosol for inhalation, as shown in FIG. 1.
Further, in an optional implementation, the aerosol generating product 1000 is preferably made of a tobacco containing material that releases volatile compounds from a matrix when heated, or may be made of a non-tobacco material that can be suitable for electric heating smoke formation after being heated. The aerosol generating product 1000 is preferably made of a solid matrix, which may include one or more of a powder, particles, fragments, strips, or sheets of one or more of vanilla leaves, dried flower, herbaceous crops with volatile fragrance, tobacco leaves, homogeneous tobacco, and expanded tobacco; or the solid matrix may contain additional tobacco or non-tobacco volatile aroma compounds to be released when the matrix is heated.
As shown in FIG. 1, after the aerosol generating product 1000 is received by the aerosol generating device 100, part of the aerosol generating product, such as a filter tip, is exposed outside the aerosol generating device 100, which is beneficial for smoking by a user.
The structure of an aerosol generating device according to an embodiment of this application may be shown in FIG. 1, and the overall appearance of the device is generally configured in the shape of a flat cylinder. An external component of the aerosol generating device 100 includes:
a housing 10 basically defining an outer surface of the aerosol generating device, and having an interior that is of a hollow structure, thereby forming an assembly space for necessary functional components such as an electronic device and a heating device. The housing 10 has a proximal end 110 and a distal end 120 that are opposite in a length direction. During use, the proximal end 110 is an end close to a user to facilitate operation, accommodating, heating, and smoking of the aerosol generating product 1000. The distal end 120 is an end away from the user.
The proximal end 110 is provided with a receiving port 111, and the aerosol generating product 1000 can be received into the housing 10 through the receiving port 111 to be heated or removed from the housing 10.
The distal end 120 is provided with an air inlet hole 121. The air inlet hole 121 is configured to allow outside air to enter the housing 10 during smoking.
In some examples, the shell may be formed from a metal or an alloy such as stainless steel or aluminum. Other appropriate materials include various plastics (such as polycarbonate), metal-plating over plastic, a ceramic, and the like.
Further, as shown in FIG. 1, the aerosol generating device 100 further includes:
a chamber for accommodating or receiving an aerosol generating product 1000. During use, the aerosol generating product 1000 can be removably received in the chamber through the receiving port 111.
As shown in FIG. 1, the aerosol generating device 100 further includes:
an air channel 150 located between the chamber and an air inlet port 121, and then, during use, the air channel 150 provides a channel path from the air inlet port 121 into the chamber/aerosol generating product 1000, as shown by the arrow R11 in FIG. 1.
Further, as shown in FIG. 1, the aerosol generating device 100 further includes:

a battery cell 130 for supplying power, where preferably, the battery cell 130 is a rechargeable direct current battery cell 130 and can be charged by an external power source; and
a circuit board 140 in which a circuit is arranged or integrated, configured to control heating or operation of the aerosol generating device 100.

Further, as shown in FIG. 1, the aerosol generating device 100 further includes:
a heater 30 at least partially surrounding and defining the chamber. When the aerosol generating product 1000 is received in the housing 10, the heater 30 at least partially surrounds or encloses the aerosol generating product 1000 and performs heating from a periphery of the aerosol generating product 1000. When received in the housing 10, the aerosol generating product 1000 is at least partially accommodated and held in the heater 30.
Further, referring to FIG. 2, the heater 30 is configured substantially in an elongated tubular shape, and includes:
a tubular substrate 31. The substrate 31 is made of a material with good thermal conductivity, such as a ceramic, glass, or quartz. During use, the chamber for accommodating and holding the aerosol generating product 1000 is at least partially defined by the substrate 31. The substrate 31 is electrically insulated. In practice, the substrate 31 includes no elemental metal, or the substrate 31 includes no elemental metal pipe such as an aluminum pipe, a stainless steel pipe, a copper pipe, or an alloy. In some implementations, the tubular substrate 31 has a length of about 15 mm to 60 mm; and the tubular substrate 31 has an inner diameter of about 5.4 mm to 7.8 mm. In some specific implementations, the substrate 31 made of a ceramic material may include at least one of ceramic oxides or ceramic nitrides such as alumina, silicon oxide, boron oxide, zirconium oxide, and iron oxide. The substrate 31 made of the above-mentioned glass or ceramic material has a thermal conductivity of about 1 W/m.k to 30 W/m.k.
In some other implementations, the aerosol generating product 1000 is surrounded or enclosed by the substrate 31 by a length greater than 30 mm.
Further, referring to FIG. 2, the heater 30 further includes:
a heating element 32 at least partially surrounding or enclosing the substrate 31. During use, the substrate 31 heats the aerosol generating product 1000 by receiving or transferring heat from the heating element 32.
In some implementations, the heating member 32 includes a resistance heating element; and the heating element 32 can generate heat through resistance Joule heat when a direct current flows through the heating element 32. In some implementations, the heating element 32 is made of a metal material, a metal alloy, graphite, carbon, a conductive ceramic or another composite material of a ceramic material and a metal material, with appropriate impedance. An appropriate metal or alloy material includes at least one of nickel, cobalt, zirconium, titanium, a nickel alloy, a cobalt alloy, a zirconium alloy, a titanium alloy, a nickel chromium alloy, a nickel iron alloy, an iron chromium alloy, an iron chromium aluminum alloy, an iron manganese aluminum-based alloy, or stainless steel, and the like. Alternatively, in some varied implementations, the heating member 32 may further include an electromagnetic induction heating element, an infrared heating element, or the like.
In the above-mentioned implementations, the heating element 32 and the substrate 31 are thermally conductive with each other. The substrate 31 generates heat by receiving heat from the heating element 32, and then heats the aerosol generating product 1000 received in the substrate 31. In this implementation, the heating element 32 can generate heat through resistance Joule heat, induction heating, or the like. Alternatively, in some other implementations, the substrate 31 is infrared-transparent, and the heating element 32 is an electro-induced infrared radiation coating, so that the electro-induced infrared radiation coating can radiate infrared rays that penetrate through the substrate 31 when a current is supplied, and the infrared rays are received by the aerosol generating product 1000, to heat the aerosol generating product 1000.
In some implementations, the infrared radiation layer is composed of oxides of at least one metal element, such as Mg, Al, Ti, Zr, Mn, Fe, Co, Ni, Cu, Cr, and Zn, and the coating of these metal oxides can be heated to a proper temperature when electrified, to radiate far infrared rays. The thickness of the infrared radiation layer may preferably be controlled at 30 µm to 50 µm. The infrared radiation layer may be formed on a surface of the substrate 31 by spraying the oxides of the above-mentioned metal elements on an outer surface of the tubular substrate 31 by atmospheric plasma spraying and then curing.
Alternatively, in some other varied implementations, the heater 30 may include only a heating element 32, and a chamber is formed through surrounding or defining by the heating element 32, to accommodate the aerosol generating product 1000 and directly transfer heat to the aerosol generating product 1000 for heating.
Further, referring to FIG. 2 and FIG. 3, the heater 32 is configured in a cylindrical shape surrounding or enclosing the substrate 31. An extension dimension of the heating element 32 in a length direction of the heater 30 is smaller than that of the substrate 31. For example, in some specific implementations, the heating element 32 has a length greater than 20 mm to 50 mm. Specifically, for example, as shown in FIG. 2, the heater 30 includes a first end portion 310 and a second end portion 320 facing away each other in the length direction. In the specific implementation, the first end portion 310 and the second end portion 320 are defined by two ends of the substrate 31 in the length direction.
There is a spacing 313 between the heating element 32 and the first end portion 310, and the spacing 313 is approximately 3 mm to 10 mm. There is a spacing 314 between the heating element 32 and the second end portion 320, and the spacing 314 is approximately 3 mm to 10 mm. After assembly, the heating element 32 does not completely wrap or enclose the outer surface of the substrate 31, so that the outer surface of the substrate 31 has a first exposed area defined by the spacing 313 close to the first end portion 310. The outer surface of the substrate 31 has a second exposed area defined by the spacing 314 close to the second end portion 320. During assembly, the heater 30 is supported by arranging, in the aerosol generating device 100, a clamping or supporting component such as a PEEK ring, which is bonded to the first exposed area defined by the spacing 313 and the second exposed area defined by the spacing 314.
Further, referring to the embodiments shown in FIG. 2 and FIG. 3, the heating element 32 is a resistance heating layer formed outside the tubular substrate 31 by spraying, deposition, or the like. In this embodiment, the resistance heating layer is annular around at least part of the substrate 31. In this embodiment, the resistance heating layer is closed in a circumferential direction of the heater 30. In some implementations, the heating element 32 in the form of the resistance heating layer formed by spraying or deposition may include a nickel-chromium alloy, a nickel-iron alloy, platinum, tungsten, silver, a conductive ceramic, and the like. The thickness of the resistance heating layer of the heating element 32 may be about 0.05 mm to 0.5 mm. In practice, by selection of the material and the thickness of the resistance heating layer, when a current is guided in a longitudinal direction of the resistance heating layer based on a first electrode 371 and a second electrode 372 that are annular, it is advantageous that a resistance value of the resistance heating layer is approximately in the range of 0.5 Ω to 3 Ω.
Further, referring to FIG. 2 and FIG. 3, the heater 30 further includes:
a first electrode 371 and a second electrode 372, to supply power to the heating element 32. The first electrode 371 and the second electrode 372 each may be an electrode ring, an electrode cap, or an electrode coating formed by spraying, deposition, or the like. The first electrode 371 and the second electrode 372 are annular around the heating element 32.
The first electrode 371 is close to a first end 321 of the heating element 32, at least partially surrounds the heating element 32, and is in contact with the heating element 32 to form a conductive connection. The second electrode 372 is close to a second end 322 of the heating element 32, at least partially surrounds the heating element 32, and is in contact with the heating element 32 to form a conductive connection. The first electrode 371 is connected to the circuit board 140 by a welding conductive lead 331, and the second electrode 372 is connected to the circuit board 140 by a welding conductive lead 332, so that a current is guided in a longitudinal direction of the heating element 32.
In practice, by selection of the material and the thickness of the heating element 32, when a current is guided in the longitudinal direction of the heating element 32 based on the first electrode 371 and the second electrode 372 that are annular, it is advantageous that the resistance value of the heating element 32 is approximately in the range of 0.5 Ω to 3 Ω.
Alternatively, in some varied implementations, the heating member 32 may further include a heating mesh wound or wrapped around the substrate 31.
Further, referring to FIG. 2 and FIG. 3, the heater 30 further includes:
a temperature sensor 34, such as a temperature sensor PT1000 of a thermistor or a thermocouple, which is bonded to the heating element 32, to sense temperatures of the heating element 32 and/or the heater 30.
In this implementation, a position where the temperature sensor 34 is bonded to the heating element 32 or measures the temperature of the heating element is basically located at a longitudinal center of the heating element 32. Alternatively, a distance between the first end 321 of the heating element 32 and the position where the temperature sensor 34 is bonded to the heating element 32 is about 1/3 to 1/3 of the length of the heating element 32. In some specific implementations, a position where the temperature sensor 34 is bonded to the heating element 32 is basically close to or located at the longitudinal center of the heating element 32, so that the temperature sensor 34 is basically located in a highest-temperature area of the heating element 32. For example, FIG. 4 is a temperature field distribution diagram of a heating element 32 with a sprayed resistance heating layer. From FIG. 4, it can be seen that a highest-temperature area of the heating element 32 is basically close to or located at a longitudinal center, and the temperature in a central area is significantly higher than those in areas close to the two ends.
In some other implementations, the heater 30 further includes:
a surface insulation layer formed outside the heating element 32 and/or the first electrode 371 and/or the second electrode 372 by spraying, deposition, coating, or the like, so as to provide insulation therefor on an outer surface of the heater 30. In some implementations, the surface insulation layer is a glaze layer formed by spraying, deposition, or the like.
Alternatively, FIG. 5 is a schematic diagram of a heater 30 according to another embodiment. In this embodiment, the heater 30 includes:

an electrically-insulating substrate 31a configured in a tubular shape surrounding or defining a chamber, where the substrate 31a has a third end portion 310a and a fourth end portion 320a that face away from each other in a longitudinal direction; and
a resistance heating track 32a bonded to an outer surface of the substrate 31a through a process such as screen printing, spraying, or deposition. The resistance heating track 32a extends in a reciprocating circuitous or bending manner at a first end 321a and a second end 322a. Two ends of the resistance heating track 32a are connected to the circuit board 140 by welding leads, or the like, so that heat can be generated through resistance Joule heat when a current flows.

The resistance heating track 32a is a meandering track. The outer surface of the substrate 31a has a blank area 311a defined by the resistance heating track 32a, to mount a temperature sensor, and the like.
Further, in practice, the tube wall thickness of the substrate 31/31a made of a ceramic, glass, or quartz ranges from 0.1 mm to 0.2 mm, so that the substrate is more sensitive to controlling of temperature rising or lowering of the substrate 31/32a during a heating process.
In some implementations, the substrate 31/31a with the above-mentioned specific wall thickness cannot be prepared by current commonly-used methods such as molding or machining and punching. Further, FIG. 6 is a schematic diagram of a preparation of a substrate 31/31a with an ultra-thin tube wall having a tube wall thickness ranging from 0.1 mm to 0.2 mm according to an embodiment. In the implementation shown in FIG. 6, the substrate 31/31a obtained by injection molding of a ceramic raw material in a mold is ground from an external cylindrical surface by a centerless external cylindrical grinding process to reduce the wall thickness to 0.1 mm to 0.2 mm. The above-mentioned "centerless external cylindrical grinding" is a term for machining. In the field of machining, it refers to a grinding method in which on a centerless external cylindrical grinding machine, a workpiece is directly placed between a grinding wheel and a guide wheel without clamping and is supported by a supporting plate and/or the guide wheel, and then external cylindrical grinding of the workpiece is performed with a ground external cylindrical surface of the workpiece as a positioning reference surface. For example, in the embodiment shown in FIG. 6, the substrate 31/31a is ground from the external cylindrical surface of the substrate 31/31a by a grinding wheel 1 and a grinding wheel 2 of a centerless external cylindrical grinding machine. The substrate 31/31a is supported and guided to rotate by the supporting plate and/or a guide wheel 4 of the centerless external cylindrical grinding machine.
The external cylindrical surface of the substrate 31/31a is ground by the centerless external cylindrical grinding machine, and the tubular substrate 31/31a having a wall thickness greater than 0.6 mm and obtained by injection molding and sintering of a ceramic raw material is ground to a wall thickness of 0.1 mm to 0.2 mm.
Alternatively, in some implementations, for example, FIG. 7 is a schematic diagram in which a centerless internal cylindrical grinding machine may alternatively be used and at least one grinding wheel is inserted or extends into the substrate 31/31a for grinding. A grinding wheel 1a extends into the substrate 31/31a and is bonded to an internal cylindrical surface of the substrate 31/31a, and a grinding wheel 2a abuts against the external cylindrical surface of the substrate 31/31a for grinding. The substrate 31/31a is supported and rotatably pulled by a guide wheel 4a and a guide wheel 5a during the machining by the centerless internal cylindrical grinding machine. Through machining by the internal cylindrical grinding machine, the tubular substrate 31/31a having a wall thickness greater than 0.6 mm and obtained by injection molding and sintering of a ceramic raw material in a mold is ground to a wall thickness of 0.1 mm to 0.2 mm.

Further, in practice, according to the three-point bending strength test standard: GBT6569-2006, strengths of an alumina ceramic substrate 31/31a with a tube wall of 0.18 mm and an alumina ceramic substrate 31/31a with a tube wall of 0.6 mm were tested by a three-point bending strength tester. In test results in the three-point bending strength test, strength results of an upper endpoint, a middle point and a lower endpoint are shown in the following table.

Three-point bending strength test results
Alumina ceramic substrate 31/31a with a tube wall of 0.6 mm				Alumina ceramic substrate 31/31a with a tube wall of 0.18 mm
Number of tests	Upper endpoint	Middle point	Lower endpoint	Number of tests	Upper endpoint	Middle point	Lower endpoint
1	228.1	386.1	155	1	59.8	133.7	54.1
2	237	404.5	179.1	2	52.2	101.1	68.2
3	224.4	332	241.8	3	52.8	133.8	45.7
4	253.8	380	170.3	4	67.1	136.8	51.6
5	254.7	314.1	154.8	5	61.3	136.3	62.1
Average / N	239.6	363.3	180.2	Average / N	58.64	128.34	56.34

In the above three-point bending strength test, the ceramic tube substrate 31/31a having a wall thickness of 0.6 mm and obtained by direct injection molding and sintering was cylindrically ground and thinned to a ceramic tube substrate 31/31a having a wall thickness of 0.18 mm, with the strength significantly reduced. The compressive strength of all test sites of the thinned substrate 31/31a remains more than 40 N, which is completely feasible for a heating element 32 with a deposited or sprayed resistance heating layer or track.
FIG. 8 is a temperature rise curve of a heating process of a heater 30 using an alumina ceramic substrate 31/31a with a tube wall of 0.18 mm and an alumina ceramic substrate 31/31a with a tube wall of 0.6 mm according to an embodiment. In the comparison shown in FIG. 8, the substrate 31/31a has an inner diameter of 5.7 mm and a length of 49 mm, and power supplied to the heater 30 is 30 W. From the comparison results in FIG. 8, it took about 29s for the alumina ceramic substrate 31/31a with a tube wall of 0.18 mm to rise from room temperature to a target temperature of 320°C, and it took about 48s for the alumina ceramic substrate 31/31a with a tube wall of 0.6 mm to rise from room temperature to the target temperature of 320°C. Furthermore, the heater 40 with an alumina ceramic substrate 31/31a having a wall thickness of 0.18 mm has higher temperature sensitivity. It took less than 30s for the alumina ceramic substrate 31/31a with a tube wall of 0.18 mm to rise from room temperature to the target temperature of 320°C.
Further, FIG. 9 is a schematic diagram of a heating curve of an aerosol generating product 1000 within a predetermined time according to an embodiment. As shown in FIG. 9, the predetermined time is set based on an amount of the aerosol that can be generated by the aerosol generating product 1000 and smoking duration (for example, about 4 min) that the user is willing to accept. The heating curve having the predetermined time includes the following.
Time stage S1 (time 0 to t1, which may be, for example, about 10s): the temperature rapidly rises from room temperature to a first target temperature T1 for preheating; and the first target temperature is, for example, 350°C.
Time stage S2 (time t1 to t2, which may be, for example, about 5s): the temperature drops from the first target temperature T1 to a second target temperature T2, for example, 320°C.
Time stage S3 (time t2 to t3, which may be, for example, about 230s): the aerosol generating product 1000 basically remains at the second target temperature T2 and is heated to generate an aerosol for smoking. After the smoking is completed, power supply to the heater 30 is stopped, and the heater is naturally cooled.

In some other implementations of this application, the same aerosol generating product 1000 was heated according to the heating curve with a predetermined time shown in FIG. 9 by heaters 30 using the alumina ceramic substrate 31/31a with a tube wall of 0.6 mm and an alumina ceramic substrate 31/31a with a tube wall thinned to 0.18 mm by a cylindrical grinding process, and measured energy consumption comparison results are as follows.

Energy consumption comparison of heating the aerosol generating product 1000
Alumina ceramic substrate 31/31a with a tube wall of 0.6 mm			Alumina ceramic substrate 31/31a with a tube wall of 0.18 mm
Number of tests	Output power/m Wh	Energy consumption/J	Number of tests	Output power/m Wh	Energy consumption/J
1	185.32	667.15	1	181.94	589.5
2	184.68	664.85	2	182.44	591.1
3	184.05	662.58	3	182.70	591.95
4	184.41	663.88	4	182.15	590.17
5	183.12	658.98	5	183.12	593.31
Average	184.32	663.49	Average	182.47	591.2

As can be seen from the comparison of energy consumption above, when the aerosol generating product 1000 was heated according to predetermined temperature curve for heating and smoking duration of about 240s, the heater 30 with the alumina ceramic substrate 31/31a having a tube wall of 0.18 mm was lower in energy consumption than that of the heater 30 with the alumina ceramic substrate 31/31a having a tube wall of 0.6 mm by about 60 J to 70 J. The heater 30 with the substrate 31/31a having a tube wall thickness less than 0.2 mm after thinning is beneficial for reducing energy consumption.
Alternatively, FIG. 10 is a schematic diagram of a preparation of a heater 30 with a substrate 31/31a having a tube wall thickness less than 0.2 mm according to another embodiment. The preparation of the heater 30 in FIG. 10 includes:

obtaining raw materials for forming the substrate 31/31a, such as ceramic powder, glass powder, and quartz powder, and mixing the raw materials with a liquid additive of a tape casting process to form a slurry with fluidity;
casting the slurry by a tape casting apparatus to form a film 31b with a thickness less than 0.2 mm;
printing or depositing or spraying a resistance heating layer or a track heating element 32 on the film 31b formed by tape casting; and
winding the film 31b into a tubular shape outside a tubular jig and sintering to form a substrate 31/31a with a tube wall thickness less than 0.2 mm.

It should be noted that, the specification of this application and the accompanying drawings thereof illustrate preferred embodiments of this application, but this application is not limited to the embodiments described in this specification. Further, for a person of ordinary skill in the art, improvements or modifications may be made according to the above descriptions, and all these improvements and modifications shall fall within the protection scope of the appended claims of this application.

Claims

An aerosol generating device, configured to heat an aerosol generating product to generate an aerosol, comprising:
a chamber for receiving the aerosol generating product;

an electrically-insulating substrate configured to be tubular and at least partially surround or define the chamber; and

a heating element bonded to the substrate and surrounding at least a portion of the substrate, wherein

the substrate and the heating element are thermally conductive with each other; during use, the substrate is capable of generating heat by receiving heat from the heating element, which in turn heats the aerosol generating product; and

the substrate comprises at least one of a ceramic, glass, and quartz, and a tube wall thickness of the substrate is less than 0.2 mm.
The aerosol generating device according to claim 1, wherein the substrate comprises no elemental metal.
The aerosol generating device according to claim 1 or 2, wherein the tube wall thickness of the substrate ranges from 0.1 mm to 0.2 mm.
The aerosol generating device according to claim 1 or 2, wherein the substrate is formed by cylindrical grinding of a tubular precursor on a cylindrical grinding machine to thin a tube wall.
The aerosol generating device according to claim 1 or 2, wherein the substrate is tested according to a three-point bending strength test method, and bending strengths of all test sites of the substrate are greater than 40 N.
The aerosol generating device according to claim 1 or 2, wherein the heating element comprises a heating layer formed on or bonded to the substrate.
The aerosol generating device according to claim 6, wherein the heating layer is configured in an annular shape around the substrate.
The aerosol generating device according to claim 7, wherein the substrate comprises a first end and a second end that face away from each other in a longitudinal direction;
a first electrode bonded to the substrate and arranged close to the first end; and

a second electrode bonded to the substrate and arranged close to the second end; and

the heating layer is configured to extend between the first electrode and the second electrode, and a current is guided by the first electrode and the second electrode in a longitudinal direction of the heating layer.
The aerosol generating device according to claim 1 or 2, wherein when a current is guided in a longitudinal direction of a heating layer by a first electrode and a second electrode, resistance of the heating layer ranges from 0.5 Ω to 3 Ω.
The aerosol generating device according to claim 1 or 2, wherein when the heating element performs heating at a power supply of 30 W, the substrate is configured to be heated from room temperature to 320°C within 30s.
The aerosol generating device according to claim 1 or 2, wherein the substrate has an inner diameter ranging from 5.4 mm to 7.8 mm;
and/or the aerosol generating product is surrounded or enclosed by the substrate by a length greater than 30 mm.
A heater for an aerosol generating device, comprising:
an electrically-insulating substrate configured to be tubular; and

a heating element bonded to the substrate and surrounding at least a portion of the substrate, wherein

the substrate and the heating element are thermally conductive with each other; during use, the substrate is capable of generating heat by receiving heat from the heating element; and the substrate comprises at least one of a ceramic, glass, and quartz, and the substrate has a tube wall thickness less than 0.2 mm.
A heater for an aerosol generating device, comprising:
a quartz tube; and

an infrared radiation coating sprayed or deposited on an outer surface of the quartz tube and surrounding at least a portion of the quartz tube, to radiate infrared rays into a tubular hollow of the quartz tube,

wherein the quartz tube has a tube wall thickness less than 0.2 mm.
A preparation method for a heater for an aerosol generating device, comprising:
obtaining a tubular precursor, wherein the precursor comprises at least one of a ceramic, glass, and quartz, and the precursor has a tube wall thickness greater than 0.2 mm;

grinding the tubular precursor on a cylindrical grinding machine until the tube wall thickness is less than 0.2 mm, to obtain an electrically-insulating substrate; and

forming a heating element on the substrate.