Heating assembly for aerosol generating device

Abstract

A heating assembly (200) for an aerosol generating device (100) is disclosed. The heating assembly (200) comprises a heating chamber (202) having an opening (204) for receiving an aerosol substrate. A coating of insulating material (206) is formed on a surface of the heating chamber (202). A coating of conductive material (208) at least partially covers the coating of insulating material (206). The coating of conductive material (208) is configured to function as a Joule heater when an electric current is applied thereto. The coating of insulating material (206) prevents any contact between the coating of conductive material (208) and the heating chamber (202).

Description

Technical Field

[0001] The present invention relates to a heating assembly for an aerosol generating device. More particularly, the present disclosure is applicable to a portable aerosol generating device that can be self - contained and operate at low temperatures. Such devices can heat tobacco or other suitable aerosol substrate materials by conduction, convection, and / or radiation, rather than burning them, to generate an aerosol for inhalation.

Background Art

[0002] The popularity and use of risk - reduction devices (also known as vaporizers) or risk - modification devices have grown rapidly in recent years as an aid to help habitual smokers who wish to stop using conventional tobacco products such as cigarettes, cigars, cigarillos, and roll - your - own tobacco. In contrast to burning tobacco in conventional tobacco products, various devices and systems are available for heating or warming aerosolizable substances.

[0003] Generally available risk - reduction devices or risk - modification devices are substrate - heated aerosol generating devices or heat - not - burn (HNB) devices. This type of device generates an aerosol or vapor by heating an aerosol substrate (i.e., a consumable), typically containing moist leaf tobacco or other suitable aerosolizable material, to a temperature in the range of 150°C to 300°C. By heating rather than burning or combusting the aerosol substrate, an aerosol is released that contains the components desired by the user but does not contain undesirable combustion by - products. Also, the aerosol generated by heating tobacco or other aerosolizable materials typically does not contain the burnt or bitter taste that can be unpleasant to the user and that results from combustion.

Summary of the Invention

Problems to be Solved by the Invention

[0004] It is desirable to improve the efficiency of the heating process while ensuring reliable operation of known non-combustible heating devices. It is also desirable to improve the ease of manufacturing the heating assembly. [Means for solving the problem]

[0005] According to a first aspect of the present invention, a heating assembly for an aerosol generating device is provided, comprising: a heating chamber having an opening for receiving an aerosol substrate; a coating of an insulating material formed on the surface of the heating chamber; and a coating of a conductive material at least partially covering the coating of the insulating material, wherein the coating of the conductive material is configured to function as a Joule heater when current is supplied, and the coating of the insulating material prevents any contact between the coating of the conductive material and the heating chamber.

[0006] In this way, the energy efficiency of the heating assembly is significantly improved. In particular, since the insulating and conductive material layers are formed as coatings that form direct bonds (e.g., chemical bonds) with the layers below, there are no voids or other insulating parts between the layers that would otherwise cause heat loss. This leads to improvements in the heating and cooling times of the heating chamber, and at the same time, a reliable and compact heating assembly is provided. In contrast, in conventional heating assemblies for aerosol generating devices, the heating elements are usually placed on a dielectric backing film and attached to the heating chamber using polymer wrapping such as heat-shrinkable film. Such wrapped layer configurations lead to significant heat loss due to the presence of voids. Furthermore, the need to wrap conventional assemblies with plastic film necessitates a manual manufacturing process. By using a conductive material coating as the heating element, plastic wrapping to fix the heating layer to the heating assembly is eliminated, thereby allowing the heating assembly to be manufactured using an automated process rather than a manual one. In addition, using a coating rather than a pre-formed heating element improves flexibility regarding the shape of the heating layer and the resulting properties. For example, in contrast to pre-molded heating elements that do not form a tight fit on the surface, resulting in unoptimized heat transfer, a coating of conductive material conforms to the specific shape of the underlying surface.

[0007] The term "coating" refers to a layer formed when applied to a substrate. For example, applying an insulating material to the surface of a heating chamber forms an insulating coating. Similarly, applying a conductive material to an insulating coating forms a conductive coating. Each coating does not exist as a separate layer before it is applied. In particular, a coating can be defined as a layer formed by applying a liquid, vapor, or gaseous material to the underlying substrate. This is in contrast to films such as PEEK or polyimide film, or conventional heating tracks, which are pre-formed and exist as separate layers before being applied.

[0008] Preferably, the insulating material coating is formed on the surface of the heating chamber as a rigid layer. In contrast, conventional insulating films such as PEEK or polyimide are attached to the surface of the heating chamber as a flexible layer.

[0009] Preferably, the conductive material coating is formed on top of the insulating material coating.

[0010] Preferably, the heating chamber is tubular, and the insulating material coating is formed on the circumferential surface of the heating chamber.

[0011] Alternatively, the heating chamber may be shaped as a plate or as a "C" shape. In this case, the insulating material coating may be formed on the convex portion of the heating chamber.

[0012] Preferably, the conductive material coating is chemically bonded to the insulating material coating. That is, the insulating conductive material coating 208 forms its own chemical bond with the insulating material coating 206, thereby eliminating the need for adhesives or other bonding materials.

[0013] Preferably, the conductive material coating is deposited on the insulating material coating by physical vapor deposition or chemical vapor deposition.

[0014] Preferably, the conductive material coating is a metal or a metal oxide.

[0015] In possible alternative configurations, the conductive material coating is nonmetallic, preferably carbon.

[0016] Preferably, the conductive material coating is formed on the insulating material coating as a meander pattern. In this way, the conductive material coating can provide a uniform heat distribution to the aerosol substrate while maintaining energy efficiency. Furthermore, the thermal properties of the conductive material coating can be adjusted according to the operating requirements of the heating assembly by forming the conductive material coating in different patterns. In addition, specific patterns may be formed to give the insulating material coating an additional function (e.g., a thermistor or antenna function). The patterns may form a single heater track or path, or two or more heater tracks or paths that can be heated independently or simultaneously.

[0017] Preferably, the conductive material coating is formed as a seamless surface that completely surrounds the insulating material coating in the circumferential direction of the heating chamber. In this way, the manufacturing process is simplified while ensuring that the aerosol substrate received in the heating chamber receives a uniform heat distribution.

[0018] Preferably, the conductive material coating is formed as a plurality of circumferentially spaced bands extending axially in the heating chamber. In this way, the conductive material coating can be selectively applied, for example, by a metal evaporation process, to provide concentrated heating zones depending on the configuration of the heating chamber and / or the aerosol substrate. For example, the bands may be positioned corresponding to recessed and / or flat regions of the heating chamber.

[0019] Preferably, the circumferential surface of the heating chamber on which the insulating material coating is formed is the outer surface of the heating chamber. In this way, the conductive material coating is positioned outside the heating assembly so that during operation, heat is generated in the conductive material coating and conducted to the heating chamber through the insulating material coating, thereby heating the aerosol substrate received inside the heating chamber.

[0020] Preferably, the circumferential surface of the heating chamber on which the insulating material coating is formed is the inner surface of the heating chamber. The inner surface of the heating chamber is the surface facing a cavity for receiving at least a portion of the aerosol-generating article through an opening. In this way, the conductive material coating is positioned inside the heating chamber so that, during operation, the aerosol substrate received inside the heating chamber comes into contact with the conductive material coating and is directly heated by the conductive material coating.

[0021] Preferably, the heating assembly further comprises a first electrode connected to a first axial end of the conductive material coating and a second electrode connected to a second opposite axial end of the conductive material coating, so that during use, current can flow from the first electrode to the second electrode through the conductive material coating.

[0022] Preferably, the first and second electrodes are each formed as rings surrounding the heating chamber in the circumferential direction. In this way, a compact and robust electrode configuration is provided. Furthermore, since each electrode is in direct contact with the conductive material coating around the heating chamber, a concentrated heating region can be formed.

[0023] Preferably, the heating assembly comprises local contacts of a third material on the surface of the coating of the conductive material. These local contacts can form spots to facilitate soldering or welding of wires with a solder such as lead or silver. The third material is selected to be fixed (e.g., coated) on the conductive material and can be brazed with a solder. Metals such as gold or nickel or other metals can be used for the local contacts. The third material can be applied, for example, by electroplating.

[0024] Preferably, the coating of the conductive material has a thickness of less than 100 microns. In one example, the thickness is less than 50 microns, for example, 5 - 45 microns. In this way, a thin and energy - efficient heating layer is provided.

[0025] Preferably, the outer surface of the heating chamber has one or more recessed regions extending in the axial direction of the heating chamber. In this way, the regions project inwardly towards the interior of the heating chamber, thereby increasing the degree of contact between the heating chamber and the aerosol substrate received within the heating chamber.

[0026] Preferably, the coating of the conductive material is formed to coincide with one or more recessed portions. In this way, the coating of the conductive material can preferentially heat portions adjacent to the recessed regions of the aerosol substrate, such as portions where the inward protrusions of the aerosol substrate contact. Preferably, the coating of the conductive material is further formed between two or more recessed portions. In this way, the coating of the conductive material also heats the portion of the aerosol substrate disposed between the portions where the inward protrusions of the aerosol substrate contact.

[0027] Preferably, the coating of the insulating material includes one or more of ceramic, silicone, glass, silicon oxide, carbon, and diamond-like carbon (DLC). In this way, the coating of the insulating material exhibits a high breakdown voltage and a high thermal conductivity compared to, for example, polyimide often used in conventional insulating films. Such materials also allow the use of thin coatings, thereby improving the heat transfer to the aerosol substrate received in the heating chamber. These properties advantageously shorten the heating-up time and the cooling time of the heating chamber and improve the energy efficiency of the heating assembly. Furthermore, such materials exhibit higher thermal stability than polyimide.

[0028] Preferably, the coating of the insulating material is deposited using plasma chemical vapor deposition. Preferably, depositing a layer of the insulating material using plasma chemical vapor deposition includes depositing a thin film containing diamond-like carbon (DLC) or diamond using a high-frequency electrical excitation source and a carrier gas containing CH4. Preferably, the coating of the conductive material is deposited using one of chemical vapor deposition, physical vapor deposition, inkjet, or gravure printing. For example, the coating of the conductive material can be applied using thermal evaporation, vacuum evaporation, metal beam evaporation, sputtering, pulsed laser deposition, chemical vapor deposition (CVD), or arc PVD (cathodic arc deposition).

[0029] Preferably, the coating of the conductive material is formed as a meander pattern on the coating of the insulating material and is formed using one of etching, masking, laser cutting, or screen printing.

[0030] Preferably, the coating of the conductive material contains titanium (and may optionally be composed of titanium). In another example, the coating of the insulating material may contain silver or silver ink (and may optionally be composed of silver or silver ink).

[0031] Preferably, the insulating material coating has a thickness of 0.3 to 10 microns. In this way, the efficiency of heat transfer through the insulating material coating is improved while ensuring that the heating chamber remains properly insulated.

[0032] Preferably, the heating chamber comprises one or more flat regions extending axially within the heating chamber. In this way, one or more flat regions function to press against the outer surface of the aerosol substrate received within the heating chamber, resulting in closer and more secure contact between the one or more flat regions and the aerosol substrate. This improves heat transfer from the heating chamber to the aerosol substrate.

[0033] For example, the radius of the heating chamber in the direction of one or more flat regions may be smaller than the radius of the (e.g., cylindrical) aerosol substrate received within the heating chamber, such that one or more flat regions compress one or more adjacent portions of the aerosol substrate. In contrast, the radius of the heating chamber in the direction of one or more curved regions (i.e., the region of the heating chamber between the flat regions defining the substantially cylindrical shape of the heating chamber) may be less than or equal to the radius of the (e.g., cylindrical) aerosol substrate received within the heating chamber, such that one or more curved regions do not compress adjacent portions of the aerosol substrate. Conveniently, one or more air passages can be defined along the length of the heating chamber between one or more curved regions and the aerosol substrate.

[0034] Preferably, the insulating material coating is formed on one or more flat regions. Thus, the conductive material coating formed on the insulating material coating is also positioned adjacent to one or more flat regions. In one example, the insulating material coating may be formed on the inner surface of one or more flat portions of the heating chamber. In another example, the insulating material coating may be formed on the outer surface of one or more flat regions of the heating chamber.

[0035] Preferably, the heating chamber comprises two separable body sections.

[0036] According to a second aspect of the present invention, a method for manufacturing a heating assembly according to the first aspect is provided.

[0037] Preferably, the manufacturing method provides a heating chamber having an opening for receiving an aerosol substrate, comprising: forming a coating of an insulating material on the surface of the heating chamber; and depositing a coating of a conductive material that at least partially covers the coating of the insulating material, wherein the coating of the conductive material is configured to function as a Joule heater when current is supplied, and the coating of the insulating material prevents any contact between the coating of the conductive material and the heating chamber.

[0038] Preferably, the insulating material coating is formed on the surface of the heating chamber, and the insulating material coating is deposited around the surface of the heating chamber.

[0039] Preferably, the heating chamber is tubular, and the insulating material coating is formed on the circumferential surface of the heating chamber.

[0040] Alternatively, the heating chamber may be shaped as a plate or as a "C" shape. In this case, the insulating material coating may be formed on the convex portion of the heating chamber.

[0041] According to a third aspect of the present invention, an aerosol generating device is provided that includes a heating assembly according to the first aspect.

[0042] According to a fourth aspect of the present invention, an aerosol generating system is provided comprising an aerosol generating device and an aerosol substrate according to a third aspect.

[0043] Next, embodiments of the present invention will be described as examples with reference to the drawings. [Brief explanation of the drawing]

[0044] [Figure 1] This is an aerosol generating device according to one embodiment of the present invention. [Figure 2] This is a schematic cross-sectional view of a heating assembly comprising a coating of an insulating material and a coating of a conductive material, according to one embodiment of the present invention. [Figure 3] This is a perspective view of a heating assembly comprising a coating of a conductive material formed with a meander pattern, according to one embodiment of the present invention. [Figure 4] This is a perspective view of a heating assembly comprising a coating of a conductive material formed with a meander pattern, according to one embodiment of the present invention. [Figure 5] This is a perspective view of a heating assembly according to one embodiment of the present invention, which includes a coating of conductive material that completely encloses the heating chamber in the circumferential direction. [Figure 6] This is a perspective view of a heating assembly according to one embodiment of the present invention, which includes a coating of conductive material that completely encloses the heating chamber in the circumferential direction. [Figure 7] This is a perspective view of a heating assembly according to one embodiment of the present invention, which includes a coating of a conductive material disposed adjacent to one or more flat regions of a heating chamber. [Figure 8] This is a perspective view of a heating assembly according to one embodiment of the present invention, which includes a coating of a conductive material disposed adjacent to one or more recessed regions of a heating chamber. [Figures 9A-9C] This is a perspective view of a heating assembly according to one embodiment of the present invention, which includes a coating of a conductive material placed inside a heating chamber. [Figure 10] This is a perspective view of a heating assembly according to one embodiment of the present invention, which includes a coating of a conductive material formed in a meander pattern on the outside of the heating chamber. [Modes for carrying out the invention]

[0045] The drawings in this specification follow the numbering convention in which the first one or more digits correspond to the drawing number, and the remaining digits identify an element or component within the drawing. Elements or components that are similar across different drawings may be identified by using similar digits. For example, 206 refers to element "06" in Figure 2, and a similar element may be called 306 in Figure 3. Those skilled in the art will understand that the descriptions of the characteristics and configuration of each element may also apply to corresponding elements in other embodiments.

[0046] Figure 1 shows an aerosol generating device 100 according to one embodiment of the present invention. The aerosol generating device 100 is shown in an assembled configuration with its internal components visible. The aerosol generating device 100 is a heated non-combustible device, which may also be called a tobacco vapor device, and comprises a heating assembly 200 configured to receive an aerosol substrate, such as a rod of aerosol generating material (e.g., tobacco). The heating assembly 200 is operable to heat the rod of aerosol generating material without combustion to generate vapor or aerosol for the user to inhale. Naturally, it will be understood by those skilled in the art that the aerosol generating device 100 shown in Figure 1 is merely an exemplary aerosol generating device according to the present invention. Other types and configurations of tobacco vapor products, vaporizers, or e-cigarettes may also be used as aerosol generating devices according to the present invention.

[0047] Figure 2 shows a schematic cross-sectional view of a heating assembly 200 according to one embodiment of the present invention. The heating assembly 200 comprises a heating chamber 202, also called a thermally conductive shell, configured to hold an aerosol substrate, also called a consumable, inside. In particular, the heating chamber 202 defines a substantially cylindrical cavity in which a rod of the aerosol substrate can be placed. The heating chamber 202 is tubular (e.g., substantially cylindrical) and has an opening 204 located at the longitudinal end of the heating chamber 202. During use, the user can insert the aerosol substrate through the opening 204 of the heating chamber 202 so that the aerosol substrate is placed inside the heating chamber 202 and in contact with the inner surface 201 of the heating chamber 202. The length of the heating chamber 202 may be configured so that a portion of the aerosol substrate protrudes through the opening 204 of the heating chamber 202, i.e., protrudes out of the heating assembly 200, and can be received in the user's mouth.

[0048] The heating chamber 202 includes, and preferably is made of, a metal, to efficiently transfer heat to the aerosol substrate through the side walls of the heating chamber 202, while also ensuring that the heating chamber 202 has sufficient structural stability and durability. Examples of suitable metals include steel, stainless steel, or aluminum.

[0049] The thickness of the (circumferential) side wall of the heating chamber 202 is preferably 0.1 mm or less, or more preferably 0.07 to 0.09 mm. This allows for efficient heat conduction to consumables through the side wall of the heating chamber 202 while maintaining sufficient structural stability. The heating chamber 202 has a closed end on the side opposite to the opening 204, and the closed end preferably has a thickness of 0.2 to 0.6 mm, which adds further structural rigidity to the heating chamber 202. A method for manufacturing the heating chamber 202 is described in the concurrently pending international application PCT / EP2020 / 074147.

[0050] Those skilled in the art will understand that the heating chamber 202 is not limited to being cylindrical. For example, the heating chamber 202 may be formed as a cubic, conical, hemispherical, or other shaped cavity and configured to accept an aerosol substrate of a complementary shape. Furthermore, in some embodiments, the heating chamber 202 may not completely enclose the aerosol substrate but may only contact a limited area of ​​the aerosol substrate.

[0051] For example, the heating chamber 202 is substantially cylindrical, but may have one or more elongated recessed regions that protrude inward to form elongated projections on the inner surface 201 of the heating chamber 202, as will be described later with reference to Figures 6 and 8. The recessed regions can be created by injecting a fluid into the heating chamber 202 under pressure and pressing the outer surface 203 of the heating chamber 202 to create a plurality of corresponding elongated projections running longitudinally on the inner surface 201 of the heating chamber.

[0052] In another example, the heating chamber 202 is substantially cylindrical, but may have one or more flat regions extending axially along the heating chamber 202, as will be described later with reference to Figures 5 and 7. In this case, the heating chamber 202 may be configured such that a rod of aerosol substrate received within the heating chamber 202 is compressed by one or more flat regions of the heating chamber 202. Other areas of the circumferential surface of the heating chamber (i.e., sections of the heating chamber connecting one or more flat regions) are configured not to contact the received rod of aerosol substrate, thereby forming one or more air passages along the length of the heating chamber. A coating 206 of insulating material, also called an insulating layer, surrounds the outer surface 203 of the heating chamber 202. In particular, the coating 206 of insulating material is positioned adjacent to (i.e., in contact with, abuts against) the circumferential outer surface 203 of the heating chamber 202. The insulating material coating 206 is directly bonded to the outer surface 203 of the heating chamber 202, that is, a chemical bond is formed between the insulating material coating 206 and the heating chamber 202. In Figure 2, the insulating material coating 206 is shown to extend along only a portion of the length of the outer surface 203 of the heating chamber 202. However, it will be understood by those skilled in the art that in other embodiments, the insulating material coating 206 may extend along the entire length of the heating chamber 202. Furthermore, it will be understood by those skilled in the art that the insulating material coating 206 may only partially surround the outer surface of the heating chamber 202.

[0053] The insulating material coating 206 preferably comprises a material exhibiting a high dielectric breakdown voltage (e.g., about 100 volts or more) and high thermal conductivity. For example, the insulating material coating 206 may include ceramic, silicone, glass, silicone oxide, carbon, or a combination thereof. In another example, the insulating material coating 206 may include (and may be composed of) diamond-like carbon (DLC). Preferably, the insulating material coating 206 has a thickness of 0.3 to 10 microns, more preferably 0.5 to 6 microns. Such properties improve heat transfer to the aerosol substrate received in the heating chamber 202 while ensuring that the heating chamber 202 remains insulated. Conveniently, the heating and cooling times of the heating chamber 202 are reduced, which can improve the energy efficiency of the heating assembly 200.

[0054] The conductive material coating 208 covers (i.e., coats) the insulating material coating 206. In other words, the conductive material coating 208 is directly bonded to the insulating material coating 206 on the side opposite to the side that is joined to the heating chamber 202. In this way, a chemical bond is formed between the conductive material coating 208 and the insulating material coating 206, thereby ensuring complete adhesion between the layers.

[0055] The conductive material coating 208 is configured to act as a Joule heater. In other words, the conductive material coating 208 is configured to release heat in response to the flow of electric current. This physical phenomenon may be called Joule heating, resistance heating, or ohmic heating. During use, the conductive material coating 208 may be powered from a power source such as a battery (not shown) so that its temperature rises and thermal energy is transferred to the heating chamber 202 via the insulating material coating 206. The aerosol substrate received in the heating chamber 202 is conductively heated by the heating chamber 202 to generate an aerosol for the user to inhale.

[0056] The conductive material coating 208 preferably contains a metal. For example, the conductive material coating 208 may preferably mainly contain titanium (and may optionally consist of titanium). In another example, the insulating material coating may contain silver or silver ink (and may optionally consist of silver or silver ink). In particular, a silver ink coating may be formed by applying silver ink flakes in butyl carbitol onto the insulating material coating, for example by screen printing, and then curing the composition, for example, curing at 340°C for 20 minutes. The coating may also contain carbon or metal oxide semiconductors or conductors. Examples of metal oxides include TiO2, NiO, TiN, or TiB2. The electrical conductivity of the material is 10 (at 20°C). -3 S / m greater than, preferably 10 2 S / m greater than, most preferably 10 -3 ~10 7 It is S / m.

[0057] The conductive material coating 208 can be deposited or printed using a variety of techniques, including chemical vapor deposition (CVD), physical vapor deposition (PVD), thermal deposition, vacuum deposition, metal beam deposition, sputtering, pulsed laser deposition, arc PVD (cathode arc deposition), inkjet, gravure printing, or screen printing.

[0058] Those skilled in the art will understand that the heating chamber 202 is not a resistance heater and therefore should not be subjected to current. Thus, the insulating coating 206 conveniently prevents contact between the conductive coating 208 and the heating chamber 202, thereby preventing a short circuit between the heating element 208 and the heating chamber 202, while allowing for efficient heat transfer from the conductive coating 208 to the heating chamber 202. In other words, the insulating coating 206 separates the conductive coating 208 from the heating chamber 202, ensuring that no current flows from the conductive coating 208 to the heating chamber 202.

[0059] The heating chamber 202, the insulating coating 206, and the conductive coating 208 form direct bonds with each other (i.e., they are chemically bonded at their interfaces), so there are no gaps or other insulating areas between these components. Conveniently, this limits heat loss during operation and significantly improves the energy efficiency of the heating assembly 200.

[0060] In the embodiment shown in Figure 2, the conductive material coating 208 is formed as a continuous surface that completely surrounds the insulating material coating 206 in the circumferential direction of the heating chamber. That is, the conductive material coating 208 covers the insulating material coating 206 so that no portion of the insulating material coating 206 is exposed, at least in the circumferential direction. However, as will be discussed later, in alternative embodiments, the conductive material coating 208 may only partially cover the insulating material coating 206 and may be arranged in various patterns and configurations.

[0061] Figure 3 shows a heating assembly 300 according to another embodiment of the present invention. In this embodiment, a conductive material coating 308 is formed on an insulating material coating 306 as a meander pattern or meandering pattern. For example, the conductive material coating 308 may be shaped by etching, masking, laser cutting, or screen printing to form the illustrated pattern. Naturally, it will be understood by those skilled in the art that the specific pattern formed by the conductive material coating 308 may vary depending on the functional requirements of the heating assembly 300. The pattern forms an electrical path so that when current is supplied to the conductive material coating 308 during use, it moves along the electrical path and generates thermal energy.

[0062] Figure 4 shows a heating assembly according to another embodiment of the present invention, in which the conductive material coating 408 is formed as a meander pattern in a configuration different from the pattern in Figure 3. The conductive material coating 408 is patterned to form strips of conductive material that curve across the insulating material coating 406. The paths formed by the conductive material coating 408 function as electrical paths through which current is supplied, providing a uniform heat distribution to the aerosol substrate received in the heating chamber 402.

[0063] In other examples, the conductive material coatings 308, 408 may be patterned and / or shaped for one or more additional functions. For example, the conductive material coatings 308, 408 may be shaped to form a specific pattern that functions, for example, as a thermistor or an antenna.

[0064] Figures 5 and 6 show two alternative embodiments in which the conductive material coatings 508, 608 are applied as a continuous surface of conductive material that completely surrounds the insulating material coatings 506, 606. In other words, the conductive material coatings 508, 608 surround the heating chambers 502, 602 circumferentially so that the insulating material coatings 506, 606 are not exposed.

[0065] In Figure 5, the heating chamber 502 is a tubular member having two flat regions 512 formed on both sides of the heating chamber 502 and extending in the axial direction of the heating chamber 502. However, it will be understood by those skilled in the art that there may be three or more flat regions 512, and that the flat regions 512 may be spaced apart on the circumference of the heating chamber 502. The region of the heating chamber 502 between the flat regions 512 may be called a curved region.

[0066] Conveniently, when an aerosol substrate having a diameter larger than the distance between the flat regions 512 (e.g., a cylindrical aerosol substrate) is received into the heating chamber 502 during use, the flat regions 512 compress the area of ​​the aerosol substrate in contact with it. Thus, a flat interface is formed between each flat region 512 and the aerosol substrate, resulting in improved heat transfer. At the same time, the diameter of the aerosol substrate may be smaller than the radial distance between the curved regions of the heating chamber 502 so that the curved regions do not come into contact with the aerosol substrate, and two air passages are defined between the aerosol substrate and the curved regions of the heating chamber 502 along the length of the heating chamber 502.

[0067] The heating assembly 510 further comprises two electrodes 510 (also called electrical connectors) positioned at axially separated regions of the conductive material 508, for example, at both ends of the conductive material 508 in the axial direction of the heating chamber 502. Each electrode 510 is configured as a wire or band that surrounds the coating 508 of the conductive material circumferentially and forms a ring that contacts the coating 508 of the conductive material. In this way, an electrical path can be formed from one electrode 510 to the other electrode 510 through the coating 508 of the conductive material. Thus, when current is supplied to one of the electrodes 510, the current travels through the coating 508 of the conductive material, generating heat around the entire circumference of the heating chamber 502.

[0068] In Figure 6, the heating chamber 602 is a tubular member having a plurality of recessed regions 614, which may also be called longitudinal depressions. The recessed regions 614 extend parallel to the length of the heating chamber 602 and form elongated projections on the inner surface 601 of the heating chamber 602. In other words, the projections protrude inward into the cavity. Therefore, when the aerosol substrate is received into the heating chamber 602, the elongated projections increase contact with the aerosol substrate, resulting in a concentrated heating effect. The conductive material coating 608 is formed as a uniform layer on the insulating material coating 606. In particular, the conductive material coating 608 is also formed within the recessed regions 614. Similar to Figure 5, the heating assembly 600 includes annular electrodes 610 surrounding the conductive material coating 608 and in contact with the conductive material coating 608. In both embodiments, since the electrodes 510, 610 are in contact with the conductive material coatings 508, 608, the electrodes 510, 610 can form concentrated heating regions.

[0069] Figures 7 and 8 show two alternative embodiments in which the conductive material coatings 708, 808 are formed only on selected areas of the heating chambers 702, 802. In particular, the conductive material coatings 708, 808 are formed as a plurality of circumferentially spaced bands that extend axially along the heating chambers 702, 802.

[0070] In Figure 7, the heating chamber 702 has the same shape as the heating chamber 502 in Figure 5, but the conductive material coating 708 (and the underlying insulating material coating 706, as can be seen from reference numeral 206 in Figure 2) is positioned only adjacent to the flat region 712 of the heating chamber 702 and does not extend around the entire circumference of the heating chamber 702. That is, the conductive material coating 708 is formed as multiple (e.g., two) axial bands that coincide with the flat region 712 of the heating chamber 702. In this way, when current is supplied through the electrode 710, the conductive material coating 708 provides a concentrated heating effect that preferentially heats the region of the aerosol substrate received in the heating chamber 702 that is adjacent to the flat region 712. The electrode 710 is formed as a substantially annular band or wire, which surrounds the heating chamber 702 and contacts the conductive material coating 708 on both sides of the heating chamber 702 corresponding to the flat region 712 at points axially separated along the length of the heating chamber 702. In the illustrated embodiment, the insulating material coating 706 is also formed only on the flat region 712, coincides with (i.e., just below) the conductive material coating 708, and does not surround the heating chamber 702. As a result, the electrode 710 is positioned such that it contacts only the heating chamber 702 and, in particular, the conductive material coating 708 adjacent to the flat region 712 of the heating chamber 702. In this way, the electrode 710 does not directly contact the outer surface of the heating chamber 702, and a gap is provided between the electrode 710 and the outer surface of the heating chamber 702 in the rest of the circumference of the heating chamber 702.

[0071] However, in an alternative embodiment, it will be understood by those skilled in the art that the insulating material coating 706 can completely surround the heating chamber 702 in the circumferential direction. In this case, the electrode 710 can come into contact with the heating chamber 702, and in particular with the insulating material 706 and the conductive material 708 around the entire circumference of the heating chamber 702.

[0072] In Figure 8, the heating chamber 802 has the same shape as the heating chamber 602 in Figure 6, but the conductive material coating 808 (and the underlying insulating material coating 806) is positioned to coincide with (within) the recessed region 814 and does not extend around the entire circumference of the heating chamber 802. In other words, the conductive material coating 808 is formed as multiple axial bands extending adjacent to the recessed region 814. In this way, when current is supplied via the electrode 810, the conductive material coating 808 provides a concentrated heating effect that preferentially heats the portion of the aerosol substrate received in the heating chamber 802 that is adjacent to the recessed region 814. In other words, the corresponding portion of the aerosol substrate that comes into contact with the elongated projections formed on the inner surface 801 of the heating chamber 802 receives more thermal energy. In this case as well, the electrode 810 is formed as an annular band or wire that surrounds the heating chamber 802 and contacts the conductive material coating 808 in the recessed region 814 and in regions that are axially separated along the length of the heating chamber 802.

[0073] In the illustrated embodiment, the insulating material coating 806 is formed only within the recessed region 814 and does not surround the heating chamber 802, which is coincident with (i.e., just below) the conductive material coating 808. As a result, the electrode 810 is positioned such that it contacts only the heating chamber 802 and, in particular, the conductive material coating 808 adjacent to the recessed region 814 of the heating chamber 802. In particular, the electrode may be circumferentially positioned around the heating chamber and formed in a ring away from the heating chamber, with radial projections (e.g., small strips or tabs) that contact the recessed region 814. In this way, the electrode 810 does not directly contact the outer surface of the heating chamber 802, and a gap is provided between the electrode 810 and the outer surface of the heating chamber 802 in the rest of the circumference of the heating chamber 802.

[0074] However, in an alternative embodiment, it will be understood by those skilled in the art that the insulating material coating 806 can completely surround the heating chamber 802 in the circumferential direction. In this case, the electrode 810 can come into contact with the heating chamber 802, and in particular with the insulating material 906 and the conductive material 908 around the entire circumference of the heating chamber 802.

[0075] The axial bands of the conductive material coatings 708 and 808 can be formed using various deposition or printing techniques, such as metal deposition or screen printing, as discussed earlier.

[0076] In alternative embodiments, it will be understood by those skilled in the art that the multiple circumferentially spaced bands of conductive material 708, 808 and the underlying insulating material 706, 806 may instead be formed on the inner surfaces 701, 801 of each heating chamber 702, 802. For example, the insulating material coating 706 may be formed as multiple (e.g., two) axial bands on the inner surface 701 of the flat region 712 of the heating chamber 702. The conductive material coating 708 may be formed on the insulating material coating 706, thereby forming corresponding axial bands covering the conductive material exposed inside the heating chamber 702. Similarly, the insulating material coating 806 may be formed as multiple (e.g., two) axial bands on the inner surface 801 of the heating chamber 808, coinciding with the recessed region 814. The conductive material coating 808 may be formed on the insulating material coating 806, thereby forming corresponding axial bands covering the conductive material exposed inside the heating chamber 802. In other words, the conductive material 808 protrudes into the interior of the heating chamber 802.

[0077] Figures 9A, 9B, and 9C show various perspective views of the heating assembly 900 according to another embodiment of the present invention. In contrast to the embodiments shown earlier, the heating assembly 900 comprises an insulating material coating 906 formed on the inner surface 901 of the heating chamber 902. A conductive material coating 908 covers the insulating material coating 906 so that the conductive material coating 908 is positioned inside the heating chamber 902. Thus, when the aerosol substrate is received into the heating chamber 902, the conductive material coating 908 comes into direct contact with the aerosol substrate and transfers heat.

[0078] As shown in Figure 9A, the conductive material coating 908 is formed as a meander pattern adjacent to each flat region 912 of the heating chamber 902. However, in an alternative embodiment, the conductive material coating 908 may be formed as a seamless surface completely surrounding the inner surface 901 of the heating chamber 902. Furthermore, as discussed earlier, it will be understood by those skilled in the art that the shape of the heating chamber 902 can be varied.

[0079] In this embodiment, the insulating material coating 906 is directly beneath the conductive material coating 908; that is, the two coatings are precisely aligned so that the insulating material coating 906 is not exposed. However, in an alternative embodiment, the conductive material coating 908 may only partially cover the insulating material coating 906. For example, the insulating material coating 906 may extend circumferentially across the entire inner surface 901 of the heating chamber 902.

[0080] As shown in Figures 9A and 9B, the heating chamber 902 comprises two separable body sections. The conductive material coating 908 is configured to form an electrical path that enters and exits the heating chamber 902 through the interface between the body sections. Thus, the conductive material coating 908 can be safely connected to a power source without exposing the conductive material coating 908 at the opening 904 of the heating chamber 902.

[0081] The separate body sections of the heating chamber may be formed from a heat-resistant polymer material such as PEEK. These body sections may be manufactured by injection molding. These body sections may be assembled to form the heating chamber by press-fitting and / or bonding (such as ultrasonic welding or adhesive bonding). Each body may be equipped with coupling elements along the assembly joints to provide proper guidance and fit during assembly.

[0082] Those skilled in the art will understand that in alternative embodiments, the heating chamber 902 may be formed as a single unit rather than having separable body sections. Those skilled in the art will also understand that the heating chambers of all the embodiments described above may comprise two separable body sections.

[0083] Figure 10 shows a perspective view of a heating assembly 1000 according to another embodiment of the present invention. The heating assembly 1000 corresponds to the heating assembly 900 of Figures 9A, 9B, and 9C, in that a coating 1008 of conductive material is formed as a meander pattern adjacent to each flat region 1012 of the tubular heating chamber 1002. However, in this embodiment, an insulating material coating 1006 is formed on the outer surface 1008 of the heating chamber 100. The conductive material coating 1008 is formed on top of the insulating material coating 1006 so that the conductive material coating 1008 directly covers the insulating material coating 1006 and follows the same meander pattern.

[0084] In Figure 10, the heating chamber 1002 is shown to be formed as a single unit; however, those skilled in the art will understand that in alternative embodiments, the heating chamber 1002 may also comprise two separable body sections, as described with respect to Figures 9A, 9B, and 9C.

Claims

1. A heating assembly for an aerosol generating device, A heating chamber having an opening for receiving an aerosol substrate, A coating of insulating material formed on the surface of the heating chamber, The coating comprises a conductive material coating that at least partially covers the insulating material coating, The coating of the conductive material is configured to function as a Joule heater when current is supplied. The insulating material coating prevents any contact between the conductive material coating and the heating chamber. The conductive material coating is deposited on the insulating material coating by physical vapor deposition or chemical vapor deposition. Heating assembly.

2. The heating assembly according to claim 1, wherein the heating chamber is tubular, and the coating of the insulating material is formed on the circumferential surface of the heating chamber.

3. The heating assembly according to claim 1 or 2, wherein the coating of the conductive material is chemically bonded to the coating of the insulating material.

4. The heating assembly according to any one of claims 1 to 3, wherein the coating of the conductive material is a metal, a metal oxide, or carbon.

5. The heating assembly according to any one of claims 1 to 4, wherein the coating of the conductive material is formed on the coating of the insulating material as a meander pattern.

6. The heating chamber according to any one of claims 2 to 4, wherein the coating of the conductive material is formed as a seamless surface that completely surrounds the coating of the insulating material in the circumferential direction of the heating chamber.

7. The heating chamber according to any one of claims 2 to 4, wherein the coating of the conductive material is formed as a plurality of bands that extend in the axial direction of the heating chamber and are spaced apart in the circumferential direction.

8. The heating chamber according to any one of claims 2 to 7, wherein the circumferential surface of the heating chamber on which the insulating material coating is formed is the outer surface of the heating chamber.

9. The heating assembly according to any one of claims 2 to 7, wherein the circumferential surface of the heating chamber on which the insulating material coating is formed is the inner surface of the heating chamber.

10. The heating assembly according to any one of claims 1 to 9, further comprising a first electrode connected to a first axial end of the coating of the conductive material and a second electrode connected to a second opposite axial end of the coating of the conductive material, wherein, during use, current can flow from the first electrode to the second electrode through the coating of the conductive material.

11. The heating assembly according to claim 10, wherein the first electrode and the second electrode are each formed as rings surrounding the heating chamber in the circumferential direction.

12. The heating assembly according to any one of claims 1 to 11, comprising local contacts of a third material deposited on the surface of the coating of the conductive material, wherein the local contacts are configured to be connected to an electric wire using a brazing material.

13. The heating assembly according to any one of claims 1 to 12, wherein the outer surface of the heating chamber has one or more recessed regions extending in the axial direction of the heating chamber, and the coating of the conductive material is formed to coincide with the one or more recessed regions.

14. To provide a heating chamber having an opening for receiving an aerosol substrate, Forming a coating of insulating material on the surface of the heating chamber, The method involves forming a coating of a conductive material on the coating of the insulating material, wherein the coating of the conductive material at least partially covers the coating of the insulating material, the coating of the conductive material is configured to function as a Joule heater when current is supplied, and the coating of the insulating material prevents any contact between the coating of the conductive material and the heating chamber. Includes, The conductive material coating is deposited on the insulating material coating by physical vapor deposition or chemical vapor deposition. A method for manufacturing a heating assembly for an aerosol generating device.

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