Heating chamber for aerosol generation devices

Abstract

The present invention relates to a heating chamber (13) for an aerosol generating device (1), configured to receive and hold an aerosol generating article (2) therein, wherein the heating chamber comprises: a heating element (131) configured to provide heat to an aerosol generating article, and a fixation element (132) configured to fix the heating element in place, wherein the heating chamber has an inner surface (139) which is configured to interface with and heat the aerosol generating article when the aerosol generating article is received within the heating chamber, and the inner surface is formed by the heating element and the fixation element.

Description

[0001] HEATING CHAMBER FOR AEROSOL GENERATION DEVICES

[0002] FIELD OF THE INVENTION

[0003] The invention relates to aerosol generation devices. Specifically, the invention relates to heating chambers for aerosol generation devices, aerosol generation devices, and a manufacturing method of the heating chambers. The aerosol generation devices and, in particular, the heating chambers of the aerosol generation devices are designed and suitable for aerosol generation articles comprising tobacco or other suitable aerosol substrate materials to be heated, rather than burned, to generate an aerosol for inhalation.

[0004] TECHNICAL BACKGROUND

[0005] The popularity and use of reduced-risk or modified-risk devices (also known as vaporizers) has grown rapidly in the past few years as an aid to assist habitual smokers wishing to quit smoking traditional tobacco products such as cigarettes, cigars, cigarillos, and rolling tobacco. Various devices and systems are available that heat or warm aerosolisable substances as opposed to burning tobacco in conventional tobacco products.

[0006] A commonly available reduced-risk or modified-risk device is the heated substrate aerosol generation device or heat-not-burn device. Devices of this type generate an aerosol or vapor by heating an aerosol substrate that typically comprises moist leaf tobacco or other suitable aerosolisable material. Heating an aerosol substrate, but not combusting or burning it, releases an aerosol that comprises the components sought by the user but not adverse and undesired by-products of combustion and burning. Furthermore, the aerosol produced by heating the tobacco or other aerosolisable material does not typically comprise off- or unexpected taste resulting from combustion and burning, and the substrate therefore does not require sugars and other additives that maybe added to such materials to make the smoke and / or vapour more palatable for the user.

[0007] Reduced-risk or modified-risk devices require specifically designed heating cups to contain and heat the aerosol substrate. The heating cups are usually made from metal. The manufacturing of the heating cups is thus typically complex and involves multiple steps. To heat the aerosol, capillary wicks or coil heaters are connected to the metal cup from the outer side of the metal cup, which makes the heating cup relatively large. Accordingly, the capillary wicks or coil heaters need to heat up the whole metal cup, and only then the tobacco heating starts to generate aerosol for consuming. This creates significant heat losses and battery consumption. Additionally, as the metal cup is a good heat conductor, it further increases the heat losses.

[0008] Therefore, there is a need for a heating chamber for portable aerosol generation systems that is easy to manufacture, compact in size and can effectively and efficiently heat the aerosol generation substrate.

[0009] SUMMARY OF THE INVENTION

[0010] Some, or all of the above objectives are achieved by the invention as defined by the features of the independent claims. Preferred embodiments of the invention are defined by the features of the dependent claims.

[0011] According to a first aspect of the present disclosure, there is provided a heating chamber for an aerosol generating device, configured to receive and hold an aerosol generating article therein, wherein the heating chamber comprises: a heating element configured to provide heat to an aerosol generating article, and a fixation element configured to fix the heating element in place, wherein the heating chamber has an inner surface which is configured to interface with and heat the aerosol generating article when the aerosol generating article is received within the heating chamber, and the inner surface is formed by the heating element and the fixation element.

[0012] The heating chamber of this invention places the heater in direct contact with the tobacco substrate so as to make the heating more efficient and effective, as it is lower in thermal losses and batteiy use, while the structure of the heating chamber maintains the mechanical stiffness of the heating chamber.

[0013] In a second aspect of the present disclosure, according to the first aspect, the heating element is configured to provide heat by resistive heating. In a third aspect of the present disclosure, according to the first or the second aspects, the heating element is a wire.

[0014] In a fourth aspect of the present disclosure, according to any one of the above aspects, the heating element is a coil.

[0015] In a fifth aspect of present disclosure, according to any one of the above aspects, the heating element comprises and preferably is made of nickel-chrome.

[0016] The arrangements of the second to the fifth aspects allow for a faster heat-up time.

[0017] In a sixth aspect of the present disclosure, according to any one of the preceding aspects, the fixation element comprises and preferably is made of a thermal resistant material that can withstand heat up to at least 350 °C, preferably at least 500 °C, more preferably at least 700 °C, even more preferably at least 1,000 °C, and most preferably at least 1,250 °C.

[0018] In a seventh aspect of the present disclosure, according to any one of the above aspects, the fixation element comprises or preferably consists of carbon fiber or glass fiber, preferably E-glass fiber.

[0019] The arrangement of seventh aspect provides fixation elements with a very low thermal conductivity which minimizes heat losses.

[0020] In an eighth aspect of the present disclosure, according to any one of the above aspects, the heating chamber has one and only one opening that is configured to receive the aerosol generating article.

[0021] In a nineth aspect of the present disclosure, according to any one of the above aspects, the heating element is embedded within the fixation element.

[0022] In a tenth aspect of the present disclosure, according to any one of the above aspects, the heating element comprises a plurality of heating elements arranged such that at least a part of the inner surface is formed by the plurality of heating elements and the fixation element in an alternating manner.

[0023] In an eleventh aspect of the present disclosure, according to any one of the above aspects, one or more heating elements have the shape of a ring. In a twelfth aspect of the present disclosure, according to any one of the above aspects, at least two of the heating elements are electrically connected and mutually parallel to each other.

[0024] In a thirteenth aspect of the present disclosure, according to any one of the above aspects, the heating chamber comprises a plurality of fixation elements, and at least two of the heating elements and the fixation elements are arranged adjacent to each other in an alternating manner to form the inner surface.

[0025] In a fourteenth aspect of the present disclosure, according to any one of the above aspects, one or more fixation elements have the shape of a ring.

[0026] In a fifteenth aspect of the present disclosure, according to the eleventh and fourteenth aspects, at least two of the ring-shaped heating elements and the ring-shaped fixation elements are arranged in a stacked manner.

[0027] The arrangements of the nineth to fifteenth aspects provides a more stable and stiff structure.

[0028] In a sixteenth aspect of the present disclosure, according to any one of the above aspects, the heating element and fixation element are arranged horizontally or vertically with regard to an insertion direction of the aerosol generating article into the heating chamber.

[0029] In a seventeenth aspect of the present disclosure, according to any one of the above aspects, the heating chamber consists of the heating element and the fixation element.

[0030] In an eighteenth aspect of the present disclosure, according to any one of the above aspects, the heating chamber comprises a heat resistant coat which is made of a thermal resistant material that can withstand heat up to at least 350 °C, preferably at least 500 °C, more preferably at least 700 °C, even more preferably at least 1,000 °C, and most preferably at least i,25O°C.

[0031] In a nineteenth aspect of the present disclosure, according to the above aspect, the heat resistant coat comprises or preferably is made of epoxy resin.

[0032] The arrangement of the heat resistant coat of the present invention further minimizes the heat losses. According to a twentieth aspect of the present disclosure, there is provided a manufacturing method of a heating chamber for an aerosol generating device and for receiving and holding an aerosol generating articles therein, comprising the steps of: applying a heating element and a fixation element on a mold so as to form an inner surface formed by the heating element and the fixation element and facing the mold, and removing the mold.

[0033] Compared to the manufacturing of conventional heating chambers for aerosol generating devices, the manufacturing steps in the method disclosed here are significantly reduced.

[0034] In a twenty-first aspect of the present disclosure, according to the above aspect, the method comprises the steps of: connecting the heating element with two wires, preferably by soldering, to form two electrodes, and connecting the two wires to a power source to form an electric circuit.

[0035] In a twenty-second aspect of the present disclosure, according to the twentieth or twenty-first aspects, the method comprises the step of: coating the heating element and the fixation element that have been applied on the mold with a heat resistant coat covering an exterior surface of the heating element and the fixation element opposite to the inner surface.

[0036] In a twenty-third aspect of the present disclosure, according to the twentieth or twenty- first aspects, the coating step specifically comprises the steps of: submerging the heating element, the fixation element, and the mold with the heating element and the fixation element applied thereon, into a container filled with heat resistant material, removing the heating element, the fixation element, and the mold from the container with the heat resistant material coated thereon, and drying the heat resistant material, preferably with UV light. In a twenty-fourth aspect of the present disclosure, according to the above aspect, the coating step specifically comprises the steps of removing the heat resistant material on wires that were connected to the heating elements before drying the heat resistant material.

[0037] In a twenty-fifth aspect of the present disclosure, according to the twenty third aspect, the coating step specifically comprises the steps of: drilling two holes on the heat resistant coat so as to at least expose a part of the heating element, soldering the exposed part of the heating element with two wires to form two electrodes, and connecting the two wires to a power source to form a circuit.

[0038] In a twenty-sixth aspect of the present disclosure, according to any one the twentieth to twenty-fifth aspects, the step of applying the heating element specifically comprises the steps of: rotating the mold, and winding the heating element around the exterior surface of the mold.

[0039] In a twenty-seventh aspect of the present disclosure, according to any one the twentieth to twenty-sixth aspects, the step of applying the fixation element specifically comprises the steps of: rotating the mold, and winding the fixation element around the exterior surface of the mold.

[0040] In a twenty-eighth aspect of the present disclosure, according to any one the twentieth to twenty-seventh aspects, a surface of the mold facing the inner surface comprises and preferably is made of PTFE and / or ceramic material.

[0041] In a twenty-ninth aspect of the present disclosure, according to any one the twentieth to twenty-eighth aspects, the mold has a part in a shape of an aerosol generating article.

[0042] In a thirtieth aspect of the present disclosure, according to any one the twentieth to twenty-nineth aspects, the method further comprises the step of: preparing the mold with a groove on an exterior surface of the mold, and applying the heating element on the groove.

[0043] According to a thirty-first aspect of the present disclosure, there is provided an aerosol generation device, comprising the heating chamber according to any one of the first to nineteenth aspects.

[0044] BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Fig. i shows a schematic illustration of an aerosol generation device according to one embodiment of the invention;

[0046] Fig. 2 shows a schematic illustration of an aerosol generation article according to one embodiment of the invention;

[0047] Figs. 3A and 3B show exploded-view drawings of an aerosol generation device according to one embodiment of the invention;

[0048] Fig. 4A shows an exploded-view drawing of an aerosol generation device with a heating chamber and an enlarged view of the heating chamber according to one embodiment of the invention;

[0049] Fig. 4B shows a schematic cross-sectional view of the heating chamber according to Fig. 4A;

[0050] Figs. 5A and 5B show a heating chamber and an aerosol generation article according to one embodiment of the invention;

[0051] Figs. 6A and 6B show heating chambers according to two embodiments of the invention;

[0052] Figs. 7A to 7D show schematic illustrations of a heating chamber in a manufacturing process of one embodiment of the invention;

[0053] Fig. 8 is a flowchart of a method for manufacturing a heating chamber according to an embodiment of the invention; and

[0054] Fig. 9 is a detailed flowchart of a method for manufacturing a heating chamber according to an embodiment of the invention. DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0055] Preferred embodiments of the present invention are described hereinafter and in conjunction with the accompanying drawings.

[0056] As used herein, the terms “aerosol generation device” “vaporizer system”, “inhaler” or “electronic cigarette” may include an electronic cigarette configured to deliver an aerosol to a user, including an aerosol for smoking. The illustrated embodiments of the aerosol generation system in this invention are schematic, and it is also possible to combine some of the parts into single units, such as aerosol inlet and outlet, operator or computer modules, which are apparent to a person skilled in the art. An aerosol for smoking may refer to an aerosol with particle sizes of 0.5 - 7 microns. The particle size maybe less than 10 or 7 microns. The electronic cigarette maybe portable and can be used in various orientations and positions by the user. In the context of this invention, all relative terms such as up, down, upper, lower, above, beneath, and the like are positions relative to a reference position of the device, which is the position in which the device is held upright by the user. The relative terms are not intended to limit the scope of the invention to any specific orientation or position of the device, but rather to describe the relative arrangement of the components and features of the device.

[0057] [AEROSOL GENERATING SYSTEM]

[0058] Figures 1 and 2 show an aerosol generating system comprising an aerosol generating device 1 and an aerosol generating substrate 2. The aerosol generating substrate 2 is substantially planar or flat, meaning that its effective thickness is much smaller than the extensions in the other dimensions. The aerosol generating device 1 is intended to operate with the aerosol generating substrate, and in particular to heat or warm the aerosol generating substrate 2 to generate a vapor containing one or more volatile components. The vapor may typically cool and condense to form an aerosol for inhalation by a user of the device 1.

[0059] The aerosol generating device 1 comprises a mouthpiece 11 and a device body 12 extending along a device axis Y (or a longitudinal direction of the device / the insertion or extraction direction of the aerosol generating substrate 2). The device body 12 and the mouthpiece 11 are arranged successively along the device axis Y. The mouthpiece 11 has an air outlet 111 which can be made of food grade plastic material. According to the example of Figure 1, the mouthpiece 11 and the device body 12 form two different pieces. In particular, the mouthpiece 11 is designed to be removably attached to the device body 12, e.g. fixed on or next to an insertion opening 136 formed at one of the ends of the device body 12. In this case, the aerosol generating substrate 2 can be inserted into the device 1 through the insertion opening 136 when the mouthpiece 11 is removed from the device body 12. According to an alternative example (not shown), the mouthpiece 11 maybe displaceable (such as, but not limited to, slidable and / or rotatable) relative to the device body 12 from a closed position to an open position in which the aerosol generating substrate 2 can be inserted into the device 1. According to another example (not shown), the mouthpiece 11 and the device body 12 could form one single piece, i.e. the mouthpiece 11 is not removable from the device body 12. In this case, the aerosol generating substrate 2 can be inserted into the device 1 through, e.g., the outlet 111 of the aerosol generating device 1.

[0060] The device body 12 delimits an internal space of the aerosol generating device 1 receiving various elements designed to carry out different functionalities of the device 1. As shown in Figs 3A, 3B and, particularly, 4A and 4B, the internal space has a heating chamber 13, a thermal insulation case 14, a device frame 15, a power source 16 and an electronic circuitry 17. Specifically, the heating chamber 13 is configured to receive, hold and heat the aerosol substrate 2 therein. The thermal insulation case 14, preferably made of microlite or wool, is configured to insulate the heat generated from the heating chamber 13 and is arranged to contain and surround the heating chamber 13. The device frame 15 is configured to provide stable support and connect the components of the device 1 and especially the heating chamber 13. The power source 16, such as a battery (e.g., a rechargeable lithium battery which maybe replaceable), is provided for powering the device 1. The electronic circuitry 17, or a PCB, comprises a controller unit for controlling the operation of the device 1, and is configured to transmit the electrical energy provided by the battery 16 to components that need power, e.g., the heating chamber 13, through cables 134. The device body 12 further comprises an air flow path and / or air inlet for introduction of air into the heating chamber 13.

[0061] [AEROSOL GENERATING SUBSTRATE]

[0062] Referring to Figure 2, the aerosol generating substrate 2 is, for example, a flat-shaped cuboid extending along a substrate axis X and having external dimensions La x Wa x Da. In a typical example, the length La of the aerosol generating substrate 2 according to the article axis X may be in a range from 20 to 45 mm, preferably from 25 to 40 mm, more preferably from 28 to 36 mm, for example 33 mm. The width Wa may be in the range from 8 to 18 mm, preferably from io to 16 mm, more preferably from io to 14 mm, for example 12 mm. The thickness Da may be in the range from 1 to 5 mm, preferably from 1 to 3 mm, more preferably from 1 to 2 mm, for example 1.4 mm. According to different examples, the values La, Wa and Da can be selected within a range of + / - 40%. According to other examples, the aerosol generating substrate 2 may have any other suitable flat shape and / or external dimensions. Other types and configurations of tobacco aerosol products, vaporisers, or electronic cigarettes may also be provided according to the invention.

[0063] When positioned and contained in the heating chamber 13, the aerosol generating substrate 2 remains substantially flat. The aerosol generating substrate 2 typically comprises an aerosol generating material such as tobacco. The aerosol generating substrate 2 may be circumscribed by a wrapper extending around the article axis X. The wrapper may, for example, comprise paper and / or non-woven fabric and / or aluminum foil. The wrapper maybe porous or air impermeable. The aerosol generating substrate 2 may comprise tobacco strands or shreds or gathered tobacco sheets and binder. The substrate generally contains tobacco predominantly made up from tobacco leaf (or lamina) and / or stem and / or reconstituted tobacco. The substrate generally comprises an aerosol former. The aerosol former constitutes generally at least 5%, e.g. between 5 and 20% of the tobacco substrate. In order to make heat transfer more efficient, in addition to plant material and binder, thermal and / or light-conducting materials may be added into the substrate.

[0064] When the aerosol generating substrate 2 is positioned or contained in the heating chamber 13, the major surfaces (the upper and lower surfaces in Figure 2) of the aerosol generating substrate 2 face and interface the opening 136 and / or distal end 137 of the heating chamber 136. A distal end of the aerosol generating substrate 2 typically positioned at the distal end 137 of the heating chamber 13.

[0065] [HEATING CHAMBER]

[0066] Referring to Figs. 4, 5A and 5B, the heating chamber 13 is adapted to receive the aerosol generating substrate 14. Corresponding and complementary to the shape and size of aerosol generating substrate 2, the chamber 22 may form a substantially cuboid shape extending along the device axis Y. In other words, the chamber 13 is dimensioned to contain the aerosol generating substrate 2. The chamber 13 has a proximal end 136, and a distal end 137. A longitudinal axis extends between the proximal 136 and distal ends 137. In the illustrated example, the longitudinal axis of the chamber 13 corresponds to the device axis Y. In other words, the longitudinal axis is substantially parallel to the insertion direction of the aerosol generating substrate 14.

[0067] The side walls of the heating chamber 13 extend along the proximal 136 and distal ends 137 (or the device axis Y). The chamber 22 defines the (insertion) opening at the proximal end 136. The proximal end 136 is, thus, an open end of the chamber 22, configured to receive the aerosol generating substrate 2 in the heating chamber 22 in a longitudinal direction along the longitudinal axis (or the device axis Y). In other words, the proximal end 136 is arranged with one, preferably one and only one, opening for receiving the aerosol generating substrate 2. Some micro air inlets maybe arranged on the distal ends 137 and / or the walls adjacent to the distal ends 137.

[0068] The wall has an external surface 140 and an inner surface 139, which is opposite to the external surface 140, and the inner surface 139 faces an internal volume of the chamber 13 for receiving the aerosol generating article 2. The inner surface 139 is configured to interface with the surface of the aerosol generating substrate 2. In the context of this invention, the inner surface 136 interfacing with the aerosol generating article 2 does not necessarily imply that, when the aerosol generating article 2 is inserted in the heating chamber 13, it is always in contact with the inner surface 136. Rather, it can also imply that the aerosol generating article 2 contacts the inner surface 126 only during the insertion / extraction of the aerosol generating article 2, or the inner surface 136 may not be in contact with the surface of the aerosol generating article 2 at all but directly face or be exposed to the aerosol generating article 2 without any obstructions when the aerosol generating article 2 is fully inserted and received in the heating chamber. In other words, “interface” or “interfacing” does not imply that the surface 136 inevitably contacts the aerosol generating article 2 when the article 2 is contained in or during its process of inserting or extracting it from the heating chamber 13. Rather, the inner surface 136 may contact the aerosol generating article 2, when the article 2 is contained in or during the process of inserting or extracting it from the heating chamber 13.

[0069] To make the insertion of the aerosol generating article 2 easy for the user, the heating chamber has a shape similar to a vase. Specifically, the opening 136 of the heating chamber 13 has an approximately rectangular shape at its top, which is the widest part of the heating chamber 13. The heating chamber 13, specifically a part of the inner surface 139, has a curved surface that connects the main part of the heating chamber 13 (the inner surface 139). This part of the surface is concave, meaning that the horizontal cross-sections of the heating chamber 13 decrease in size as they approach the distal end 137 or the main part of the heating chamber 13. The main part of the heating chamber 13 is also approximately rectangular, but smaller than the opening in cross section. The corners of the opening 136 and the distal end 137 are preferably rounded.

[0070] A user may insert the aerosol generating substrate 2 through the opening 136 in the heating chamber 13 such that the aerosol generating substrate 2 is positioned within the heating chamber 13 and interfaces with the inner surface 201.

[0071] The heating chamber 13 comprises at least one heating element 131 and at least one fixation element 132, preferably multiple heating elements 131 and multiple fixation elements 132.

[0072] The heating element 131 is configured to provide heat to the aerosol generating article 2 through resistive heating. In preferred embodiments, the material of the heating element comprises or is titanium, stainless steel, nickel, chrome or aluminum; alloys thereof are also possible. In the most preferred embodiment, the heating element comprises and preferably is made of nickel-chrome or nickel-chromium. The resistance of the heating element 131 made of nickel-chrome increases relatively rapidly with an increasing coil temperature. The nickel- chrome is also food grade material. It has a thermal range up to 1,250 °C, which again fulfils the temperature requirement. The design of the heating element 131 and its geometry also influence the resistance of the heater by the length and diameter of the heating element. The geometry of the heating element 131 is selected to match the dimension and characteristics of the aerosol generation article 2 and such that a desired heating operation can be achieved. For the present method of establishing a temperature and resistance relationship it is advantageous that the selected material demonstrates a replicable functional relationship between resistance and temperature. The heating element 131 is preferably a heating wire, specifically a wire coil.

[0073] As shown in the figures, at least some of the coils of the heating elements 131 are in the form of a ring. In the preferred embodiment as shown Fig. 6A, all the heating elements 131 are in the shape of rings. The ring-shaped heating elements 131 are preferably closed loops that encircle the inner volume of the heating chamber 13. The ring-shaped heating elements 131 may have various shapes, such as a round, square, rectangular, or any other polygonal or curved shape, and the ring-shaped heating elements 131 do not have any haps or openings. The ring-shaped heating elements 131 may be uniform or vary in width along the circumference of the ring. In another embodiment as shown in Fig. 6B, some of the coil of the heating elements 131 have a U- shape, i.e. a shape that resembles the letter U. In other words, it has two parallel sides that are connected at the distal end of the heating chamber 13. The U-shape heating elements 131 are preferably provided perpendicular to the ring-shaped heating elements 131.

[0074] In order to make the heating more effective and efficient, the heating element(s), namely the wire coil (s) 131 is (are) arranged so as to interface with the aerosol generating article 2. In other words, a part or parts of the heating element(s) 131 form(s) at least a part of the inner surface 131. The heating element(s) 131 is (are) arranged in at least the main part of the heating chamber 13, namely the narrowest part of the heating chamber 13.

[0075] In preferred embodiments, the heating chamber 13 comprises at least two heating elements 131, preferably at least four heating elements 131, and most preferably at least eight heating elements 131; and at most sixty-four heating elements, preferably at most forty-eight heating elements, most preferably at most thirty-two heating elements.

[0076] To provide heat, the heating elements 131 is configured to release heat in response to the flow of electrical current. Although this physical effect is primarily referred to as resistive heating, it may also be referred to as Joule heating or Ohmic heating. In use, power may be supplied to the heating elements 131 from the power source 16 such as a battery through cable 134 such that the temperature of the heating elements 131 increases and heat energy is transferred directly to the aerosol generating article 2 to generate the aerosol for inhalation by the user. In a preferred embodiment, the heating chamber 13 comprises electrodes 133 made of copper and soldered to each of the resistive wire coils of the heating elements.

[0077] Due to the nature of the material, i.e., the alloy of nickel-chrome, of the heating element 131, it can be fragile and deformable in heat. Hence, the fixation elements(s) 132 arranged with the heating elements 131 support(s) the heating elements 131 so as to make the general structure of the heating chamber 13 stable. The fixation element 132 can be made of any thermal resistant material that can resist heat generated by the heating element 132, i.e., heat up to at least 350 °C, preferably at least 500 °C, more preferably at least 700 °C. even more preferably at least 1,000 °C, and most preferably at least 1,250 °C. Preferably, the fixation element 132 comprises or preferably consists of carbon fiber or glass fiber. A preferred glass fiber for forming the fixation element is E-glass fiber. Since E-glass fiber is made is alumino-borosilicate glass turned into fiber which is flexible and easy to wrap it makes it a natural choice for this application. Alumino-borosilicate is certified for permanent contact with food. Alternatively, also a carbon fiber may be considered which has a similar temperature range; however, it has greater heat conductivity compared to the glass fiber, which would result in lower power efficiency. The fixation elements 132 are preferably in the form of a wire or a coil as well.

[0078] Similar to the heating element 131, as shown in figures, especially Fig. 6A, some of the coils of the fixation elements 132 are also in the form of a ring. The ring-shaped fixation elements 132 are preferably closed loops that encircle the inner volume of the heating chamber 13. The ring-shaped fixation element 132 has generally the same shape as the heating element 131. The ring-shaped heating element 131 may be uniform or vary in width along the circumference of the ring, and may have the same width as the heating element 131.

[0079] In order to increase the thermal insulation performance of the heating chamber 13, the heating chamber 13 may further comprise a coat of thermal insulation materials or heat resistant materials 135 on the outside of the heating elements 131 and of the fixation elements 132. The coat 135 is at least 0.01 mm thick, preferably at least 0.1 mm thick, more preferably at least 0.25 mm thick, most preferably at least 0.5 mm thick; and at most 10 mm thick, preferably at most 5 mm thick, more preferably at most 2 mm thick, and most preferably at most 1 mm thick. In preferred embodiments, the heat resistant coat is in a form of a glass fiber epoxy coated cup, which is a thin but rigid high temperature epoxy coating. The epoxy coating is preferably made of High temp epoxy coating Dural co® 4700 or Stone Coat Epoxy resin with low thermal conductivity. The heat resist coat has multiple holes, through which the electrodes are soldered to the heating elements 131.

[0080] Fig. 4B shows a cross-section schematic view of the heating chamber assembly 13 according to an embodiment of the invention. The heating elements 131 and the fixation elements 132 form the inner surface 139 of the heating chamber 13. The ringshaped heating elements 131 and the ring-shaped fixation elements 132 are arranged in a stacked or embedded manner. In other words, the ring-shaped heating elements 131 and the ring-shaped fixation elements 132 are arranged together in a type of structure that consists of multiple ring-shaped heating elements 131, and the ring-shaped fixation elements 132 are placed on top of each other, preferably in an alternating manner, and aligned along the longitudinal axis extending between the proximal 136 and distal ends 137 of the heating chamber 13 (the device axis Y). The heat resistant coat 135 is opposite to the inner surface 139 of the heating chamber 13 and forms the external surface 140 of the heating chamber 13. Alternatively, the heating chamber 13 may not have a heat resistant coat 135, and the heating elements 131 and the fixation element 132 form the external surface 140 (not shown).

[0081] The length of the heating chamber 13 may be such that a portion of the fully inserted aerosol generation article 13 protrudes through the opening 136 in the heating chamber 13. Accordingly, the length of the heating chamber 13 along the device axis Y may be in a range from 20 to 45 mm, preferably from 25 to 40 mm, more preferably from 28 to 36 mm, for example 33 mm. Accordingly, the width (along the device axis Y) of the heating element 131 is at least 0.01 mm, preferably at least 0.1 mm, more preferably at least 0.3 mm, most preferably at least 1 mm; and at most 23 mm, preferably at most 12 mm, more preferably at most 6 mm, and most preferably at most 3 mm.

[0082] [MANUFACTURING METHOD OF HEATING CHAMBER]

[0083] Compared to the conventional heating chamber, the heating chamber 13 of this invention is simpler and thus cheaper to manufacture. As shown in Fig. 8, the heating elements 131 and the fixation elements 132 are applied on a surface of a mold (Step Si). The mold has at least a part that is dimensioned and shaped almost identical to the shape and size of an aerosol generating article 2. Therefore, the inner surface 139 is formed on a surface of the mold. Accordingly, the inner surface 139 is formed by (a) part(s) of the heating element and the fixation element that faces the mold. The mold is preferably made of metal. Finally, the mold is removed from the heating elements 131 and the fixation elements 132 so as to form the heating chamber 13 (Step S2).

[0084] A detailed method of manufacturing a heating chamber 13 according to an embodiment of the invention, for example a heating chamber as shown in Figures 3 to 6A is depicted in Figs. 7A to 7D and 9. It will be appreciated that, in some embodiments of this invention, some of the following steps of manufacturing may be omitted.

[0085] The method begins in Step S11, in which a metal mold, specifically a metal insert 3 is provided that is in the form of a cup having a part that has substantially the same shape and size as an aerosol generating article 2. Optionally, the cup insert 3 is connected with a mechanical arm that can rotate the cup insert 3 horizontally; and the cup insert 3 may be provided with multiple grooves so as to make the application of the heating elements 131 easy. The depth of the grooves is in a range from 0.01 to 50 mm, preferably from 0.1 to 10 mm, more preferably from 0.2 to 1 mm, for example 0.3 mm.

[0086] An optional Step S11A of preparing the metal cup insert 3 may occur after Step Sil: a PTFE or ceramic coating for easier cup 3 removal in a later stage may be applied on the outer surface of the metal cup insert 3.

[0087] As shown in Fig. 7A, the heating elements 131, preferably eight resistive wire coils made of nickel-chrome alloy, are placed on the outer surface of the PTFE or ceramic coating, or the metal cup insert 3 in Step S12. Preferably, the heating elements 131 are applied on the prepared grooves.

[0088] In preferred embodiments, the metal cup insert 3 is rotated by the mechanical arm so that the heating elements 131 can be applied onto the metal cup insert 3 horizontally. Alternatively, the heating elements 131 are wrapped on the metal cup insert 3 in a horizontal manner. Herein, the horizontal direction preferably implies a direction that is parallel to the opening 136 and / or the insertion direction of the aerosol generating article 2.

[0089] An optional Step S12A of applying the heating elements 131 may occur after Step Sil: some U-shaped heating elements 131, preferably six U-shaped resistive wire coils, also made of nickel-chrome alloy, like the ones shown in Fig. 6B, may be applied on the metal cup insert 3 vertically. Herein, the vertical direction preferably implies a direction that is parallel to the side walls of the heating chamber 13 and / or perpendicular to the opening 136, at least one of the heating elements 131, and / or the insertion direction of the aerosol generating article 2.

[0090] Similar to the step of application of the heating elements 131, in Step S13, the fixation elements 132, preferably multiple E-Glass fibers, are wrapped around the metal cup insert 3. Alternatively, the metal cup insert 3 maybe rotated so as to place the E-Glass fibers 132 on the metal cup insert 3. Preferably, the fixation elements 132 are applied on at least the area of the metal cup insert 3 where the heating elements 131 are not applied. Accordingly, the internal volume, and especially the inner surface 139, of the heating chamber 13 are formed by the heating elements 131 and the fixation elements 132 as shown in Fig. 7B.

[0091] In the next Step S14, the metal cup insert 3 with the heating elements 131 and the fixation elements 132 is then submerged to a tank with epoxy resin so as to form the heat resistant coat 135 on the outside surface of the heating elements 131 and the fixation elements 132. Other than the epoxy resin, the material inside the tank may comprise polyimide or other high temperature plastics, ceramic, or fiberglass. Specifically, as shown in Fig. 7C, the epoxy resin is in the form of a liquid or gel in the tank, and the metal cup insert 3 is submerged into the tank to an extent such that at least the heating elements 131, preferably both the heating elements 131 and the fixation elements 132, are completely submerged into the tank with epoxy resin, but preferably not the complete metal cup insert 3, e.g., until the opening 136 of the heating chamber 13. Since the heating elements 131 and the fixation elements 132 are closely in contact with the metal cup insert 3, only the outside of the heating elements 131 and the fixation elements 132, but not the inner surface 139 of the heating chamber 13, are provided with the epoxy resin.

[0092] As shown in Fig. 7D, together with the heating elements 131, the fixation elements 132 and the epoxy resin applied thereon, the metal cup insert 3 is removed from the tank. Accordingly, the heat resistant coat, preferably in the form of laminates, is formed on the outside of the heating elements 131 and the fixation elements 132.

[0093] In Steps S15 and S16, in order to make the epoxy resin solid, the metal cup insert 3 is placed in the air to dry and cure the epoxy resin, preferably with UV light (Step S15C) applied on the epoxy resin to speed up the curing process.

[0094] Once the epoxy resin is cured on the outside of the heating elements 131 and the fixation elements 132, in Step S17, the metal cup insert 3 is pulled out from the heating elements 131 and the fixation elements 132 so that the heating chamber 13 is ready.

[0095] Optionally, the electrodes 133 are soldered onto the heating elements 131 right after applying the fixation elements 132 and before submerging the metal cup insert 3 (Step S13A); or after removing the metal cup insert 3 from the tank and wiping out the epoxy resin from the area for the electrodes 133 (Step S 15A), and before curing the heat resistant coat 135 (S15B); or after pulling out the metal cup insert 3 (S17B), and as the heat resist coat 135 is already cured, multiple holes (about 0.4 mm in diameter) need to be drilled, preferably on the side walls of the cured heating chamber 13 (Step 17A).

[0096] It will be appreciated that, in some embodiments of this invention, there may not be Steps S14 to S16. In other words, the heating chamber 13 does not have the thermal resist coat 135. The manufacturing of the heating chamber 13 is thus simpler and cheaper than for the conventional heating chambers that are used in the available aerosol generating devices.

[0097] [REFERENCE]

[0098] 1 aerosol generating system

[0099] 2 aerosol generating article

[0100] 11 mouthpiece portion

[0101] 111 air outlet

[0102] 12 device body

[0103] 13 heating chamber

[0104] 14 thermal insulation case

[0105] 15 device frame

[0106] 16 battery

[0107] 17 PCB / operation unit

[0108] 131 heating element / resistive wire

[0109] 132 fixation element / E-Glass fiber

[0110] 133 copper electrodes

[0111] 134 wires

[0112] 135 heat resistant coat / high temp epoxy coating

[0113] 136 proximal end / opening

[0114] 137 distal end

[0115] 139 inner surface / interfacing surface

[0116] 140 external surface

[0117] 3 mold / metal cup insert

Claims

Claims1. A heating chamber for an aerosol generating device, configured to receive and hold an aerosol generating article therein, wherein the heating chamber comprises: a heating element configured to provide heat to an aerosol generating article, and a fixation element configured to fix the heating element in place, wherein the heating chamber has an inner surface which is configured to interface with and heat the aerosol generating article when the aerosol generating article is received within the heating chamber, and the inner surface is formed by the heating element and the fixation element.

2. The heating chamber of the preceding claim, wherein the heating element is configured to provide heat by resistive heating, and the heating element is preferably a coil made of nickel-chrome.

3. The heating chamber of any one of the preceding claims, wherein the fixation element comprises and preferably is made of a thermal resistant material, that can withstand heat up to at least 350 °C, preferably at least 500 °C, more preferably at least 700 °C, even more preferably at least 1,000 °C, and most preferably at least 1,250 °C, and the fixation element preferably comprises or preferably consists of carbon fiber or glass fiber, preferably E-glass fiber.

4. The heating chamber of any one of the preceding claims, wherein the heating chamber has one and only one opening that is configured to receive the aerosol generating article.

5. The heating chamber of any one of the preceding claims, comprising a plurality of heating elements and / or a plurality of fixation elements arranged such that at least a part of the inner surface is formed by the plurality of heating elements and the fixation element in an alternating manner.

6. The heating chamber of the preceding claim, wherein one or more heating elements and / or one or more fixation elements have the shape of a ring, preferably, atleast two of the heating elements are electrically connected and mutually parallel to each other, and / or are arranged in a stacked manner.

7. The heating chamber of any one of the preceding claims, wherein the heating element and fixation element are arranged horizontally or vertically with regard to an insertion direction of the aerosol generating article into the heating chamber.

8. The heating chamber of any one of the preceding claims, consisting of the heating element and the fixation element.

9. The heating chamber of any one of the preceding claims, comprising a heat resistant coat which is made of a thermal resistant material that can withstand heat up to at least 350 °C, preferably at least 500 °C, more preferably at least 700 °C, even more preferably at least 1,000 °C, and most preferably at least i,25O°C, and preferably comprises or preferably is made of epoxy resin.

10. A manufacturing method of a heating chamber for an aerosol generating device and for receiving and holding an aerosol generating articles therein, comprising the steps of: applying a heating element and a fixation element on a mold so as to form an inner surface formed by the heating element and the fixation element and facing the mold, and removing the mold.

11. The manufacturing method of the preceding claim, comprising the step of: coating the heating element and the fixation element that have been applied on the mold with a heat resistant coat covering an exterior surface of the heating element and the fixation element opposite to the inner surface; and preferably, the coating step comprises the steps of: submerging the heating element, the fixation element, and the mold with the heating element and the fixation element applied thereon, into a container filled with heat resistant material, removing the heating element, the fixation element, and the mold from the container with the heat resistant material coated thereon, and drying the heat resistant material, preferably with UV light.

12. The manufacturing method of any one of claims 10 or 11, wherein the step of applying the heating element comprises the steps of: rotating the mold, and winding the heating element and / or the fixation element around the exterior surface of the mold.

13. The manufacturing method of any one of claims 10 to 12, wherein a surface of the mold facing the inner surface comprises and preferably is made of PTFE and / or ceramic material.

14. The manufacturing method of any one of claims 10 to 13, further comprising the step of: preparing the mold with a groove on an exterior surface of the mold, and applying the heating element on the groove.

15. An aerosol generation device, comprising the heating chamber according to any one of claims 1 to 14.

Images