Heating assembly for aerosol generating device

Abstract

A heating device for an aerosol generating device is disclosed. The heating assembly (10, 110, 210) includes an outer cylinder (14, 114, 214) having a first end and a second end, an inner cylinder (12, 112, 212) having an opening (16, 116, 216) located at the first end of the outer cylinder for receiving an aerosol forming substrate, with a vacuum-insulated space (24, 124, 224) provided between the inner cylinder and the outer cylinder, a heating element (26, 126, 226) positioned on the outward-facing surface (28, 128, 228) of the inner cylinder between the inner cylinder and the outer cylinder, and one or more parts (30, 130, 138, 230) of getter material provided on the outward-facing surface of the inner cylinder within the vacuum-insulated space.

Description

TECHNICAL FIELD

[0001] The present invention relates to a heating assembly for an aerosol-generating device, and an aerosol-generating device including the heating assembly. The present disclosure is particularly applicable to portable aerosol-generating devices that may be self-contained. In particular, the present invention relates to an aerosol-generating device in which a heating element is disposed within a vacuum chamber. BACKGROUND ART

[0002] The manufacture of electronic cigarettes that heat, rather than burn, solid or semi-solid aerosol-forming substrates including tobacco is a growing field of interest. These devices typically receive a rod of tobacco within a heating chamber. The rod is heated to release an aerosol, which can be inhaled by a user. One problem with these devices is that the heater that supplies heat to the heating chamber may also unnecessarily heat the rest of the device. In compact devices, this can be disadvantageous as the temperature of the outer surface of the device held by the user can become unacceptably high. To mitigate such effects, some aerosol-generating devices have been provided with a vacuum chamber that allows the heater to be positioned at a distance from the outer surface. This can provide thermal separation between the heating chamber and the user-held outer surface.

[0003] Within such aerosol-generating devices, it is desirable to improve the efficiency of the heating operation so that the battery life of the device can be extended. To this end, vacuum insulators have been implemented in aerosol-generating devices to thermally insulate the cavity that heats the aerosol substrate, thereby limiting heat loss to the external environment. SUMMARY OF THE INVENTION PROBLEMS TO BE SOLVED BY THE INVENTION

[0004] An object of the present invention is to further improve heating efficiency and reduce undesirable heat loss. [Means for solving the problem]

[0005] According to one aspect of the present invention, a heating assembly for an aerosol generating device is provided, comprising: an outer cylinder having a first end and a second end; an inner cylinder having an opening located at the first end of the outer cylinder for receiving an aerosol forming substrate, with a vacuum-insulated space provided between the inner cylinder and the outer cylinder; a heating element disposed on the outward-facing surface of the inner cylinder between the inner cylinder and the outer cylinder; and one or more components of a getter material provided on the outward-facing surface of the inner cylinder within the vacuum-insulated space.

[0006] In this way, the integrity and effectiveness of the vacuum between the inner and outer cylinders are improved. In known vacuum heating assemblies, it is known that the vacuum level in the adiabatic space, such as in a static vacuum system, is prone to degradation, which can occur due to several factors such as permeation, gas release, leakage, or contamination. To prevent or minimize such vacuum degradation, the present invention utilizes a getter material in the vacuum adiabatic space to absorb or react with any residual gas in the adiabatic space. The getter material functions by chemically reacting with or absorbing residual gases, including water vapor, hydrogen, oxygen, and other reactive species, in a vacuum system or low-pressure system. By providing an improved vacuum within the heating assembly, the overall efficiency of the heating element and aerosol generating device is also improved, which leads to faster heating times and more effective and efficient use of the device's power (e.g., battery). The improved vacuum also conveniently means that heat from the heating assembly is more effectively prevented from being transferred to the outer casing of the aerosol generating device.

[0007] During the operation of the heating assembly, the heat from the heating element increases the reactivity of the getter material, allowing it to react with any gas in the vacuum-insulated space, which helps maintain the vacuum level and improve the performance of the heating element. The present invention improves the overall reliability of the heating assembly by preventing residual gases from reacting with other components in the system, such as the inner and outer cylinders including pressure, the heating element, or any seals in the vacuum-insulated space. As is understood, any undesirable reaction of residual gases by the heating assembly (e.g., by the wall material or heating element material) is detrimental to the vacuum insulation and the performance and reliability of the heating element. Therefore, by providing one or more components of the getter material on the outward-facing surface of the inner cylinder together with the heating element, it is ensured that the getter material is in close proximity to or in contact with the heating element, providing better protection for the heating element from any undesirable reactions.

[0008] Multiple getter material components may be arranged in layers. For example, the layers of getter material may be in the form of strips circumferentially covering an inner and / or outer cylinder within a vacuum-insulated space. Each layer of the strip configuration may be spaced at predetermined distances, at regular or irregular intervals, according to design or manufacturing requirements. In another example, one or more components of the getter material may be in the form of a plug or three-dimensional structure inserted into the vacuum-insulated space. The plug may be a thick-walled cylinder, a ring, or another three-dimensional shape. For example, another three-dimensional shape may be a hexagonal nut shape to allow the gas to further increase the surface area of ​​the getter material. The getter material may also be a porous or foamed structure, allowing the gas to move through and / or within and around the structure. Further shapes or arrangements of one or more components of the getter material within a vacuum-insulated space will be apparent to those skilled in the art.

[0009] The operating temperature or working temperature of the getter material (i.e., the temperature or temperature range at which the getter material effectively absorbs or reacts with residual gas in a vacuum-insulated space) can depend on various factors, including the shape of the inner and / or outer cylinder (and the vacuum-insulated space formed within it), power dissipation in the outer and inner cylinders, and the proximity of the getter material to the heating element. Typically, the operating temperature range of the getter material may be 150°C to 500°C. The getter material is typically effective in the low to medium vacuum range, commonly referred to as "coarse vacuum" or "medium vacuum." This range is typically from atmospheric pressure (760 Torrell or 1 Bar) to about 10°C. -3 It can reach up to Torre (0.1 Pa).

[0010] Preferably, one or more components of the getter material are provided on at least a portion of the inward-facing surface of the outer cylinder. In this way, one or more components can be optimally positioned within the vacuum-insulated space. Some getter materials are more effective at absorbing residual gas at lower temperatures, and therefore, one or more components of the getter material may be placed on at least a portion of the inward-facing surface of the outer cylinder (i.e., within the vacuum-insulated space) at a predetermined distance from heating elements so as not to overheat. One or more components of the getter material provided on the outward-facing surface of the inner cylinder may include a first getter material, and one or more components of the getter material provided on the inward-facing surface of the outer cylinder may include a second getter material, the first getter material being different from the second getter material.

[0011] Preferably, one or more components of the getter material completely cover the inward-facing surface of the outer cylinder. In this way, the getter material is provided on the inward-facing surface of the outer cylinder with a larger surface area to absorb or react with any undesirable residual gases.

[0012] One or more components of the getter material are provided on the outward-facing surface of the inner cylinder. In this way, the getter material may also be provided on the inner cylinder of the heating chamber. By positioning the getter material on the outward-facing surface of the inner cylinder, the getter material is positioned closer to the heating element (which is similarly positioned on the same outward-facing surface). Preferably, one or more components of the getter material on the outward-facing surface of the inner cylinder at least partially cover the heating element. In this way, a portion of one or more components of the getter material may be positioned directly on the heating element on the outer surface of the inner cylinder. As can be seen, by covering the heating element with the getter material, it is possible to further prevent the heating element from coming into contact with and reacting with any gas in the vacuum, which is undesirable.

[0013] Preferably, one or more components of the getter material include at least one of the following: barium-based getter alloy, zirconium-based getter alloy, titanium or titanium-based getter alloy, indium or indium-based getter alloy, or non-evaporative getter alloy. Different getter materials can operate effectively at different temperatures, so one or more getter materials may be used to optimize the vacuum integrity and heating element performance of the heating chamber. Non-evaporative getter materials may have a lower operating temperature range, such as 150°C to 250°C, which is advantageous for getter materials in applications where higher temperatures may be harmful or impractical. Different getter materials may be placed on different surfaces within the vacuum-insulated space.

[0014] According to another aspect of the present invention, an aerosol generating device is provided which is configured to generate an aerosol for a user to inhale, the aerosol generating device comprising a heating assembly according to the first aspect and a power supply for supplying power to the heating element.

[0015] According to another aspect of the present invention, a method is provided for manufacturing a heating assembly for an aerosol generating device, the method comprising: providing an outer cylinder having a first end and a second end; providing an inner cylinder having an opening for receiving an aerosol forming substrate; arranging a heating element on the outward-facing surface of the inner cylinder between the inner cylinder and the outer cylinder; providing one or more components of a getter material; arranging the inner cylinder and the outer cylinder such that the opening is positioned at the first end of the outer cylinder and an insulating space is provided between the outer cylinder and the inner cylinder, wherein one or more components of the getter material are used on at least the outward-facing surface of the inner cylinder within the insulating space; and forming a vacuum within the insulating space.

[0016] Preferably, one or more components of the getter material are used on at least a portion of the inward-facing surface of the outer cylinder. By using the getter material on the inward-facing surface of the outer cylinder, one or more components can be optimally positioned within the vacuum-insulated space. Preferably, one or more components of the getter material are used to completely cover the inward-facing surface of the outer cylinder. In this way, the getter material can be effectively provided on the outer cylinder with a larger surface area.

[0017] One or more components of the getter material are used on at least the outward-facing surface of the inner cylinder. In this way, the surface of the inner cylinder may also be used to position one or more components of the getter material in order to improve the integrity of the vacuum and the performance of the heating element. Preferably, one or more components of the getter material are used in the heater cup so as to at least partially cover the heating element.

[0018] Preferably, the method further includes activating one or more components of the getter material. In this way, one or more components of the getter material can be made capable of effectively reacting with or absorbing residual gases in a vacuum-insulated space, or can be activated in this manner. Activation of the getter material may be carried out during the manufacture of the heating chamber. As will be understood by those skilled in the art, different types of getter materials can be activated in different ways. Preferably, activating one or more components of the getter material includes heating the heating assembly to an activation temperature, preferably the activation temperature being higher than the operating temperature of the heating assembly. In this way, thermally activated getter materials such as barium-based getter alloys, zirconium-based getter alloys, titanium getter alloys, indium getters, and non-evaporable getters (typically composed of a combination of reactive metals such as zirconium, vanadium, and other elements) are used.

[0019] Activation of one or more components of the getter material may involve heating the inner and / or outer cylinders to a temperature of approximately 400°C to 900°C, depending on the type of getter material used. This heating causes the getter to release vapor and become chemically active, ready to react with residual gases during cylinder operation. During operation of the heating chamber within the aerosol generating device, the temperature of the getter material typically experiences a significantly lower operating temperature (ranging from 150°C to 500°C) than the temperature used in the initial activation process. During operation, vapor may be released from one or more components of the getter material within the operating temperature range, and the vapor reacts with residual gases in the cylinder to help maintain the vacuum level and improve the performance of the heating element.

[0020] Preferably, the activation of one or more components of the getter material is carried out while a vacuum is formed. During the activation process, vapor may be released into an adiabatic space. To optimize the vacuum formation process, the activation of one or more components of the getter material may be carried out simultaneously with the formation of the vacuum. Preferably, a pump may be used to form the vacuum.

[0021] Here, embodiments of the present invention will be described as examples with reference to the drawings. Brief Description of the Drawings

[0022] [Figure 1] It is a perspective view of an aerosol-generating device including a heating assembly. [Figure 2] It is a schematic cross-sectional view of a heating assembly. [Figure 3] It is a schematic cross-sectional view of a heating assembly. [Figure 4] It is a schematic cross-sectional view of a heating assembly. Modes for Carrying Out the Invention

[0023] As described herein, vapor is generally understood to refer to a substance in the gaseous phase at a temperature below its critical temperature, that is, vapor can be condensed into a liquid by increasing its pressure without lowering the temperature, while an aerosol is a state in which fine solid particles or liquid droplets are suspended in air or another gas. However, it should be noted that in the present specification, the terms "aerosol" and "vapor" may be used interchangeably, particularly with respect to the form of inhalable media generated for inhalation by a user.

[0024] Figure 1 shows an aerosol-generating device 2 according to an embodiment of the present invention. The aerosol-generating device 2 is shown in an assembled configuration that allows exemplary internal components to be viewed. The aerosol-generating device 2 is a non-combustion heating device, which may also be referred to as a tobacco vapor device, and includes a heating assembly 4 configured to receive an aerosol-generating material, for example, an aerosol substrate such as a tobacco rod. The aerosol-generating device 2 may include a power source such as a battery, and a control circuit for controlling the supply of power from the power source to the heating assembly 4. The heating assembly 4 is operable to heat the rod of aerosol-generating material, rather than burning it, to produce vapor or aerosol for inhalation by a user. As will be appreciated by those skilled in the art, the aerosol-generating device 2 shown in Figure 1 is, of course, merely an exemplary aerosol-generating device according to the present invention. Other types and configurations of tobacco vapor products, vaporizers, or electronic cigarettes may also be used as the aerosol-generating device according to the present invention.

[0025] Figure 2 shows a schematic diagram of a heating assembly 10 having an inner tube 12 and an outer tube 14. The heating assembly 10 includes an opening 16 defined by the inner tube 12 disposed at a first end of the heating assembly 10, through which opening an aerosol-forming substance or consumable can be received into the cavity 18 of the heating assembly 10. In other words, the opening 16 functions as an access point for inserting a consumable into the heating assembly 10 in the assembled configuration.

[0026] The inner tube 12 comprises a metallic material (e.g., stainless steel) with good thermal conductivity properties. The inner tube 12 further includes a base wall 20 that provides a closed end of the inner tube 12, such that the inner tube 12 forms a heater cup shape. In use, the base wall 20 functions to limit the insertion depth of the consumable. The outer tube 14 also comprises a metallic material such as steel or stainless steel that is easily formed into a tubular or cylindrical shape.

[0027] In this example, the inner cylinder 12 is radially positioned within the inward-facing surface 22 of the outer cylinder 14 so that, when viewed from above or below, the inner and outer cylinders appear as concentric cylinders, i.e., the cup and tube are shown as concentric circles (not shown) parallel to the longitudinal axes of the inner and outer cylinders. In alternative examples, the inner cylinder 12 and / or outer cylinder 14 may be formed in other types of cross-sectional shapes, such as squares or polygons.

[0028] A vacuum 24 surrounds the inner and outer cylinders of the heating assembly 10. Those skilled in the art will understand that the term "vacuum" refers to a space in which the pressure is significantly lower than atmospheric pressure due to the removal of free matter, especially air. The quality of the vacuum formed between the inner cylinder 12 and the outer cylinder 14 can be low vacuum, medium vacuum, or high vacuum.

[0029] A heating element 26 is provided on the outward-facing surface 28 of the inner cylinder 12 (i.e., the heating element is located within a vacuum 24). The heating element 26 is an electrically resistive track that can be printed or coated onto the inner cylinder 12. The heating element 26 is arranged circumferentially around the outward-facing surface 28 of the inner cylinder 12 in a square wave shape, where the heater track can be traced upward from the base wall 20 when the inner cylinder 12 is facing the opening 16, thereafter the heater track changes direction and continues in an iterative manner back toward the base wall 20. The heating element 26 may be provided in other shapes or patterns, as will be apparent to those skilled in the art. Alternatively, the heating element 26 may be laminated on the inner cylinder 12.

[0030] A layer of getter material 30 is placed on the inward-facing surface 22 of the outer cylinder 14 within the vacuum 24 to maintain the integrity of the vacuum 24 and the effectiveness of the heating element 26 throughout the life of the heating assembly 10. As described above, the getter material 30 functions by absorbing or reacting with any residual gas that may form (e.g., by gas release) or leak into the vacuum space (e.g., by permeation) during the operating life of the heating assembly 10. The layer of getter material 30 is deposited circumferentially around the entire inward-facing surface 22 of the outer cylinder 14 to maximize the surface area of ​​the getter material.

[0031] Electrical wires 32 connect the heater 26 to a power supply or a printed circuit board assembly (PCBA) (not shown). The heating assembly 10 also optionally includes thermocouple or thermistor wires (not shown) that can be connected to the PCBA to monitor and / or control the temperature of the heating element 26. The electric wires 32 and thermocouple / thermistor wires are formed into a base wall portion 34 for the outer cylinder 14. Other techniques (such as holes or appropriate seals) may be used to pass the wires through the base wall portion 34, which will be apparent to those skilled in the art.

[0032] The heating assembly 10 further includes a vacuum line 36 located within a base wall portion 34, which may be connected to a vacuum pump (not shown) to form a vacuum during the manufacturing of the heating assembly 10. In another example (not shown), a vacuum 24 may be formed between the inner cylinder 12 and the outer cylinder 14 by assembling the heating assembly in a vacuum or low-pressure environment. Further methods for surrounding a vacuum in the heating assembly will be apparent to those skilled in the art.

[0033] Figure 3 shows a schematic diagram of another heating assembly 110 having an inner cylinder 112 and an outer cylinder 114, with a vacuum 124 surrounding them. The inner cylinder 112 defines an opening 116 through which consumables can be received into a cavity 118 of the heating assembly 110. The heating assembly 110 also includes a heating element 126 positioned on the outward-facing surface 128 of the inner cylinder 112, and electrical wires 132 connecting the heating element 126 to a power source. Similar to the heating assembly 10 in Figure 2, a layer of getter material 130 is provided on the inward-facing surface 122 of the outer cylinder 114 to react with any undesirable residual gases in the vacuum 124 during the operating life of the heating assembly 110.

[0034] In this specific example in Figure 3, multiple layers 138 of getter material are also provided on the outward-facing surface 128 of the inner cylinder 112. Conveniently, the multiple layers 138 of getter material on the inner cylinder 112 can more easily capture / absorb heat from the heating element 126 during operation, so that the getter material is within its optimal operating temperature range (to absorb / react with residual gases).

[0035] Multiple layers 138 of getter material are provided as strips of getter material positioned between the heater tracks (which have a square wave shape on the inner cylinder 112) of the heating element 126. In this example, the getter material on the inner cylinder 112 is arranged as individual strips between the heater tracks of the heating element 126.

[0036] In an alternative example (not shown), the getter material may be deposited on the inner cylinder 112 as a single layer that can at least partially cover (i.e., be placed on) the heating element 126.

[0037] Figure 4 shows a schematic diagram of another heating assembly 210 having an inner cylinder 212, an outer cylinder 214, and a vacuum 224 surrounded between the inner and outer cylinders. The heating assembly 210 includes an opening 216 at one end of the inner cylinder 212 through which consumables can be received into the cavity 218 of the heating assembly 210. The heating assembly 210 also includes a heating element 226 positioned on the outward-facing surface 228 of the inner cylinder 212 and electrical wires 232 connecting the heating element 226 to a power source.

[0038] In this specific example in Figure 4, multiple components 230 of the getter material are provided on the inward-facing surface 222 of the outer cylinder 214 to react with any undesirable residual gases in the vacuum 224 during the operation of the heating assembly 210. The multiple components 230 of the getter material are provided as a ring of getter material (e.g., a thick-walled cylindrical shape) inserted into the space between the inner cylinder 214 and the outer cylinder 214, arranged circumferentially around the inward-facing surface 222 of the outer cylinder 214 toward the base wall portion 234 of the outer cylinder 212. In this example, the ring of getter material 230 is located in the vacuum 224 away from the heating element 226 to limit the degree of heating of the getter material when the heating element 226 is generating heat / operating. Electrical wires 232 pass through a central hole (not shown) in the ring of getter material 230 to connect the heating element 226 to the power supply.

[0039] The advantage of the example in Figure 4 is that the getter material is deposited in the vacuum 224 at a location that does not interfere with the manufacturing process of the heating elements in the heating assembly 210 (i.e., away from the heating elements 226 on the inner cylinder 212). As will be understood by those skilled in the art, the getter material ring 230 is three-dimensional, and other three-dimensional structures or shapes may be used. The ring may be a porous structure such as foam, which may allow gas to pass through the porous structure.

[0040] In this particular example, the getter material 230 is a non-evaporative getter material having a low operating temperature range (i.e., a temperature range in which the getter material optimally absorbs / reacts with residual gas). Therefore, no getter material is provided on the outer cylinder 214 adjacent to the heating element 226 (on the transverse axis of the outer cylinder), nor is any getter material provided on the inner cylinder 212.

[0041] As will be understood by those skilled in the art, different types of getter materials and getter materials of different shapes or structures may be deposited at different positions on the outer and / or inner cylinders, depending on different getter material properties (e.g., reactivity, operating temperature range, etc.), design requirements, and / or manufacturing capabilities.

Claims

1. A heating assembly for an aerosol generating device, An outer cylinder having a first end and a second end, An inner cylinder having an opening located at the first end of the outer cylinder for receiving an aerosol-forming substrate, wherein a vacuum-insulated space is provided between the inner cylinder and the outer cylinder, A heating element is disposed on the outward-facing surface of the inner cylinder between the inner cylinder and the outer cylinder, One or more components of the getter material are provided on the outward-facing surface of the inner cylinder within the vacuum-insulated space. A heating assembly, including a heating assembly.

2. The heating assembly according to claim 1, wherein one or more components of the getter material are provided on at least a portion of the inward-facing surface of the outer cylinder.

3. The heating assembly according to claim 2, wherein one or more components of the getter material completely cover the inward-facing surface of the outer cylinder.

4. The heating assembly according to claim 1, 2, or 3, wherein one or more components of the getter material on the outward-facing surface of the inner cylinder at least partially cover the heating element.

5. One or more components of the getter material are barium-based getter alloys, zirconium-based getter alloys, titanium or titanium-based getter alloys, indium or indium-based getter alloys, or non-evaporable getter alloys. The method according to any one of claims 1 to 4, comprising one or more of the following.

6. an aerosol generating device configured to generate an aerosol for the user to inhale, A heating assembly according to any one of claims 1 to 5, A power supply for supplying power to the aforementioned heating element and Aerosol generating device, including

7. A method for manufacturing a heating assembly for an aerosol generating device, An outer cylinder having a first end and a second end is provided, An inner cylinder having an opening for receiving an aerosol-forming substrate is provided, The heating element is placed on the outward-facing surface of the inner cylinder between the inner cylinder and the outer cylinder, The provision of one or more getter material components, The inner cylinder and the outer cylinder are arranged such that the opening is positioned at the first end of the outer cylinder and a heat insulating space is provided between the outer cylinder and the inner cylinder, wherein one or more components of the getter material are used on at least the outward-facing surface of the inner cylinder within the heat insulating space. Forming a vacuum within the aforementioned insulating space Methods that include...

8. The method according to claim 7, wherein one or more components of the getter material are used on at least a portion of the inward-facing surface of the outer cylinder.

9. The method according to claim 8, wherein one or more components of the getter material are used to completely cover the inward-facing surface of the outer cylinder.

10. The method according to claim 7, 8, or 9, wherein one or more components of the getter material are used on the outward-facing surface of the inner cylinder so as to at least partially cover the heating element.

11. The method according to any one of claims 7 to 10, further comprising activating one or more components of the getter material.

12. The method according to claim 11, wherein activating one or more components of the getter material includes heating the heating assembly to an activation temperature, preferably the activation temperature being higher than the operating temperature of the heating assembly.

13. The method according to claim 11 or 12, wherein the activation of one or more components of the getter material is performed while forming the vacuum.

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