Fluid-permeable heater assembly with a cap

Abstract

To provide a heater assembly for an aerosol generating system.SOLUTION: A fluid permeable heater assembly 10 for an aerosol generating system includes: a cap 12 which is provided with a hollow body having first and second cap openings and in which the first cap opening faces the second cap opening; and a fluid permeable heating element 20 which is virtually flat surface conductive, the heating element 20 configured to evaporate an aerosol-forming substrate and fitted to the cap 12 so that the heating element 20 crosses the first cap opening to extend.SELECTED DRAWING: Figure 1A

Description

Technical Field

[0001] The present invention relates to aerosol generation systems, such as hand-held electrically operated smoking systems. In particular, the present invention relates to a heater assembly for an aerosol generation system in which the aerosol-forming substrate is a liquid and is evaporated.

Background Art

[0002] There is known a hand-held electrically operated aerosol generation system comprising a device portion with a battery and control electronics, a cartridge portion with a supply of an aerosol-forming substrate held in a liquid storage portion, and an electrically operated heater assembly operating as a vaporizer. A cartridge comprising both a supply of an aerosol-forming substrate held in a liquid storage portion and a vaporizer is sometimes referred to as an "atomizer". The heater assembly may comprise a fluid-permeable heating element that contacts a capillary medium, such as an elongated wick, immersed in a liquid aerosol-forming substrate held in the liquid storage portion. The cartridge portion generally includes not only a supply of an aerosol-forming substrate and an electrically operated heater assembly, but also a mouthpiece through which the user draws aerosol into the mouth during use.

[0003] A heater assembly with a fluid-permeable heating element can have a fragile structure. The components of the heater assembly can move easily during transportation, packaging and use. It can be difficult to manufacture a cartridge with such a heater assembly.

[0004] It is desirable to provide an improved heater assembly for an aerosol generation system that allows for easy low-cost manufacture and provides a more rigid structure to prevent movement of the components of the heater assembly.

Summary of the Invention

[0005] According to a first aspect of the present invention, there is provided a fluid-permeable heater assembly for an aerosol generation system, comprising a cap including a hollow body having first and second cap openings, wherein the first cap opening faces the second cap opening, the cap, and a substantially planar, conductive, fluid-permeable heating element configured to evaporate an aerosol-forming substrate, the heating element being attached to the cap such that the heating element extends across the first cap opening.

[0006] The solution provided herein is to attach a cap having a hollow body on the heating element to improve the stability of the heating element and to provide guidance for a capillary medium that can be disposed in the hollow body of the cap. The use of the cap simplifies the manufacture of the heater assembly and can improve the rigidity of the heater assembly.

[0007] A further object of the heater assembly according to the present invention may be to cap the filled cartridge. This idea is to pre-assemble all the parts of the heater assembly and then manipulate this integrally formed component to facilitate closing of the cartridge.

[0008] As used herein, "substantially planar" means initially formed in a single plane and not rolled or conformed to a curved or other non-planar shape. The term "conductive" as used herein means formed from a material having a resistivity of 1 × 10 -4 Ωm or less. As used herein, "electrically insulating" means formed from a material having a resistivity of 1 × 10 4 Ωm or more. As used herein, "fluid-permeable" in relation to the heater assembly means that an aerosol-forming substrate (which may be in the gas phase but could also be in the liquid phase) can easily pass through the heating element of the heater assembly.

[0009] The heater assembly comprises a cap formed from a material having a high thermal decomposition temperature and capable of withstanding sudden temperature changes. The heating element is supported on the cap. The cap is preferably molded from plastic pellets. The plastic pellets may have polyether ether ketone (PEEK), liquid crystal polymer (LCP), or any other polymeric material. The cap material is preferably molded under the heating element. The cap is more preferably made of VICTREX PEEK via molding onto a mesh strip. The underside of the heating element is directed towards the first cap opening. Molding the cap under the heating element is advantageous because no additional material such as terminals needs to be attached to fix the heating element to the cap.

[0010] The cap preferably has a size sufficient to separate the liquid storage portion from the heating element by at least 1.5 millimeters, and is preferably 3 millimeters to 6 millimeters to provide a sufficient temperature drop across the cap. Advantageously, in such embodiments, the liquid storage portion can be made of a material having a lower thermal decomposition temperature, such as polyethylene or polypropylene, and is more cost - effective.

[0011] The heater assembly further comprises a substantially planar heating element that allows for simple manufacturing. Geometrically, the term "substantially planar" conductive heating element is used to mean an array of conductive filaments in the form of a substantially two - dimensional topological manifold. Thus, a substantially planar conductive heating element extends two - dimensionally along a surface that is substantially larger than a third dimension. In particular, the two - dimensional dimensions of the substantially planar heating element within its surface are at least five times larger than the third dimension perpendicular to the surface. An example of a substantially planar heating element is a structure between two substantially parallel elevated surfaces, where the distance between these two elevated surfaces is substantially smaller than the extension within that surface. In some preferred embodiments, the substantially planar heating element is planar. In other embodiments, the substantially planar heating element is bent along one or more dimensions, forming, for example, a dome shape or a bridge shape.

[0012] The term "filament" is used throughout this specification to mean an electrical path disposed between two electrical contacts. The filaments may optionally be branched or divided into several paths or filaments respectively, or may converge from several electrical paths into one path. The filaments may have a round, square, planar, or any other cross-sectional shape. The filaments may be arranged in a straight or curved manner.

[0013] The term "heating element" is used throughout this specification to mean an arrangement of one or preferably a plurality of filaments. The heating element may be, for example, an array of filaments arranged in parallel with each other. The heating element is fluid permeable. The heating element may be cut out to provide an open area when the heating element is attached across the first cap opening. The open area is preferably manufactured by cutting chamfered window slots from each side of the heating element. The filaments preferably can form a mesh. The mesh may be a woven or non-woven fabric. The mesh may be formed using different types of weaving structures or lattice structures. Alternatively, the conductive heating element consists of an array of filaments arranged parallel to each other. The mesh, array, or fabric of conductive filaments may also be characterized by its ability to hold liquid.

[0014] In a preferred embodiment, the substantially planar heating element can be composed of wires formed into a wire mesh. The mesh preferably has a plain weave design. The heating element is preferably a wire grill made from wire mesh strips.

[0015] The conductive filaments can define gaps between the filaments, and the width of the gaps can be from 10 micrometers to 100 micrometers. The filaments preferably cause capillary action within the gaps such that a liquid that will vaporize during use is drawn into the gaps, increasing the contact area between the heating element and the liquid aerosol forming substrate.

[0016] The conductive filaments may form a mesh of a size with 60 to 240 (±10 percent) filaments per centimeter. The mesh density is preferably 100 to 140 (±10 percent) filaments per centimeter. The mesh density is more preferably approximately 115 filaments per centimeter. The width of the gaps can be from 100 micrometers to 25 micrometers, preferably from 80 micrometers to 70 micrometers, more preferably approximately 74 micrometers. The percentage of the open area of the mesh, which is the ratio of the area of the gaps to the total area of the mesh, is from 40 percent to 90 percent, preferably from 85 percent to 80 percent, more preferably approximately 82 percent. Throughout this specification, such a mesh density is referred to as the "first mesh density".

[0017] Additionally, the mesh may have one or more sections with an increased mesh density (referred to as the "second mesh density"), and the gaps between the filaments are less than 5 micrometers, preferably less than 2 micrometers, more preferably approximately 1 micrometer. The one or more sections of the mesh with the increased mesh density are referred to throughout this specification as "high density regions".

[0018] The conductive filaments can have a diameter from 8 micrometers to 100 micrometers, but are preferably from 10 micrometers to 50 micrometers, more preferably from 12 micrometers to 25 micrometers. The filaments may have a round cross-section or a flat cross-section.

[0019] The area of the mesh, array, or fabric of the conductive filaments may be small (e.g., 50 square millimeters or less, preferably 25 square millimeters or less, more preferably approximately 15 square millimeters). The size is selected to incorporate the heating element within a handheld system. By sizing the mesh, array, or fabric of the conductive filaments to 50 square millimeters or less, the total amount of electrical power required to heat the mesh, array, or fabric of the conductive filaments is reduced, while ensuring sufficient contact of the mesh, array, or fabric of the conductive filaments with the liquid aerosol-forming substrate. The mesh, array, or fabric of the conductive filaments may be, for example, rectangular and may have a length of 2 millimeters to 10 millimeters and a width of 2 millimeters to 10 millimeters. The mesh preferably has dimensions of approximately 5 millimeters × 3 millimeters. The mesh or array of conductive filaments can cover an area of 30 percent to 90 percent of the open area of the first cap opening across which the heating element extends. The mesh or array of conductive filaments preferably covers an area of 50 percent to 70 percent of the open area of the first cap opening. More preferably, the mesh or array of conductive filaments covers an area of 55 percent to 65 percent of the open area of the first cap opening.

[0020] The filaments of the heating element can be formed from any material having suitable electrical properties. Suitable materials include, but are not limited to, semiconductors such as doped ceramics, "conductive" ceramics (e.g., molybdenum disilicide, etc.), carbon, graphite, metals, alloys, and composite materials made of ceramic materials and metal materials. Such composite materials may include doped ceramics or undoped ceramics. An example of a suitable doped ceramic is doped silicon carbide. Examples of suitable metals include titanium, zirconium, tantalum, and the platinum group metals.

[0021] Examples of suitable metal alloys include stainless steel, constantan, nickel-, cobalt-, chromium-, aluminum-, titanium-, zirconium-, hafnium-, niobium-, molybdenum-, tantalum-, tungsten-, tin-, gallium-, manganese-, and iron-containing alloys, as well as nickel, iron, cobalt, stainless steel-based superalloys, Timetal® (a registered trademark of Titanium Metals Corporation), iron-aluminum-based alloys, and iron-manganese-aluminum-based alloys. The filament may be coated with one or more insulators. Preferred materials for the conductive filament are stainless steel and graphite, more preferably 300 series stainless steels such as AISI 304, 316, 304L, 316L. Additionally, the conductive heating element may include combinations of the above materials. Combinations of materials may be used to improve control of the resistance of a substantially planar heating element. For example, a material having essentially high resistance may be combined with a material having essentially low resistance. This can be advantageous when either of the materials is more beneficial from other viewpoints, such as cost, machinability, or other physical and chemical parameters. Advantageously, waste losses are reduced by a substantially planar filament arrangement with increased resistance. Advantageously, a higher resistance heater allows for more efficient use of battery energy.

[0022] The filament is preferably made of wire. The wire is more preferably made of metal, and most preferably made of stainless steel.

[0023] The electrical resistance of the mesh, array, or fabric of the conductive filaments of the heating element can be from 0.3 ohms to 4 ohms. The electrical resistance is preferably 0.5 ohms or more. The electrical resistance of the mesh, array, or fabric of the conductive filaments is more preferably from 0.6 ohms to 0.8 ohms, and most preferably about 0.68 ohms. The electrical resistance of the mesh, array, or fabric of the conductive filaments is preferably at least one order of magnitude greater than the electrical resistance of the conductive contact region, and more preferably at least two orders of magnitude greater. Thereby, the heat generated by passing an electric current through the heating element is surely localized in the mesh or array of the conductive filaments. When the power supply of the system is a battery, it is advantageous that the overall resistance to the heating element is low. A low-resistance and high-current system enables high power to be supplied to the heating element. Thereby, the heating element can quickly heat the conductive filaments to a desired temperature.

[0024] The hollow body of the cap can be configured to hold a capillary medium. The heater assembly preferably comprises a piece of host material made from a capillary medium for holding a liquid aerosol-forming substrate. At least a portion of the piece of host material can be disposed within the hollow body between the first cap opening and the second cap opening.

[0025] Advantageously, the cap and the piece of host material can be sized to have approximately the same cross-sectional area. As used herein, approximately the same size means that the cross-sectional area of the cap with the first cap opening can be up to 30 percent smaller or larger than the capillary material. The shape of the internal space of the hollow body of the cap can also be similar to the shape of the capillary material so that the assembly and the material substantially overlap. The piece of host material is preferably substantially the same size and shape as the internal space of the hollow body. The internal space of the hollow body preferably has a substantially cylindrical shape. The volume of the internal space of the hollow body can be from 50 cubic millimeters to 500 cubic millimeters, preferably from 100 cubic millimeters to 250 cubic millimeters, and more preferably approximately 150 cubic millimeters.

[0026] The host material piece can be provided in at least partial contact with the heating element. When the sizes and shapes of the assembled product and the material are substantially the same, the manufacturing can be simplified and the certainty of the manufacturing process is improved.

[0027] The heater assembly preferably comprises a transport material piece made of a capillary medium for transporting the liquid aerosol-forming substrate from the host material piece to the heating element. The transport material piece can be provided in contact with the heating element. The transport material piece is preferably disposed between the heating element and the host material piece. In this case, the host material does not contact the heating element directly.

[0028] The transport material piece can be made of a material that ensures that at least a portion of the surface of the heating element extending across the first cap opening is in contact with the liquid aerosol-forming substrate. The transport material piece may be in contact with the conductive filaments. The transport material piece may extend into the gaps between the filaments. The heating element may draw the liquid aerosol-forming substrate into the gaps by capillary action. The transport material piece preferably contacts the conductive filaments substantially over the entire open area of the first cap opening.

[0029] The capillary material is a material that actively delivers a liquid from one end of the material to the other end. The capillary material can be directed to deliver the liquid aerosol-forming substrate towards the heating element in direct or indirect contact with a liquid storage portion via another capillary medium.

[0030] The capillary material can include three or more capillary materials, including one or more layers of capillary material in direct contact with a mesh, array, or fabric of the conductive filaments of the heating element to promote aerosol generation.

[0031] The capillary material may have a fibrous or spongy structure. The capillary material preferably comprises a bundle of capillaries. For example, the capillary material may comprise a plurality of fibers or threads, or other fine tubes. The fibers or threads can generally be aligned to carry the liquid aerosol-forming substrate to the heating element. Alternatively, the capillary material may comprise a sponge-like or foam-like material. The structure of the capillary material forms a plurality of small holes or tubes through which the liquid aerosol-forming substrate can be transported by capillary action. The capillary material may comprise any suitable material or combination of materials. Examples of suitable materials include sponge or foam materials, ceramic or graphite-based materials in the form of fibers or sintered powders, foamed metals or plastic materials, and fibrous materials made of spun or extruded fibers (such as cellulose acetate, polyester, or bonded polyolefins, polyethylene, terylene or polypropylene fibers, nylon fibers or ceramics). The capillary material may have any suitable capillary action and porosity for use with different liquid physical properties. The liquid aerosol-forming substrate has physical properties including but not limited to viscosity, surface tension, density, thermal conductivity, boiling point and vapor pressure that allow the liquid aerosol-forming substrate to be transported through the capillary medium by capillary action.

[0032] At least one capillary material may have a sufficient volume to ensure that a minimum amount of the liquid aerosol-forming substrate is present within the capillary material to prevent "dry heating" that occurs when an insufficient amount of the liquid aerosol-forming substrate is supplied to the capillary material in contact with a mesh, array or fabric of conductive filaments. To allow for 20 to 40 puffs by the user, a minimum volume of the capillary material may be provided. The average volume of the liquid aerosol-forming substrate volatilized during a 1 to 4 second puff is generally 1 to 4 milligrams of the liquid aerosol-forming substrate. Thus, providing at least one capillary material having a volume to hold 20 to 160 milligrams of the liquid aerosol-forming substrate can prevent dry heating.

[0033] The cap may include two or more different capillary materials. Here, the transport material piece in contact with the heating element may have a higher thermal decomposition temperature, and the host material piece in contact with the transport material piece but not in contact with the heating element may have a lower thermal decomposition temperature. The transport material piece effectively serves as a spacer that separates the heating element from the host material piece so that the host material piece is not exposed to a temperature above its thermal decomposition temperature. As used herein, "thermal decomposition temperature" means the temperature at which a material begins to decompose and loses mass by generating gaseous by-products. The host material piece may advantageously occupy a larger volume than the transport material piece and may also hold more aerosol-forming substrate than the transport material piece. The host material piece may have superior wicking performance compared to the transport material piece. The host material piece may be less expensive than the transport material piece. The host material piece may be polypropylene.

[0034] The transport material piece can separate the heating element from the host material piece by a distance of at least 0.5 millimeters, preferably 0.5 millimeters to 2 millimeters, more preferably approximately 0.75 millimeters, in order to provide a sufficient temperature drop across the transport material piece.

[0035] The cap preferably comprises a holder having a holder opening. The holder preferably covers at least a first cap opening and may be a planar disk having a thickness of from 0.25 millimeters to 5 millimeters, preferably from 0.5 millimeters to 2.5 millimeters, more preferably approximately 0.8 millimeters. The holder opening may have a size of from 10 square millimeters to 50 square millimeters, preferably from 20 square millimeters to 30 square millimeters, more preferably approximately 25 square millimeters. The holder can cover the first cap opening such that the holder opening coincides with at least a portion of the first cap opening. The heating element can be attached to the holder. The surface of the holder represents a contact area that contacts the heating element and is larger than the contact area of the cap without the holder. The holder reduces the size of the first cap opening to the size of the holder opening. Expanding the contact area between the holder and the heating element can improve the rigidity of the heater assembly and facilitate its assembly. The cap including the holder is preferably molded below the heating element.

[0036] The cap is preferably integrally formed. The integrally formed cap can include a holder.

[0037] The transport piece is preferably disposed in the holder opening. The transport piece preferably has substantially the same size and shape as the holder opening.

[0038] The cap preferably comprises at least one wall forming a hollow body extending from the holder. The wall preferably extends perpendicular to the holder. The wall preferably extends perpendicular to the surface of the heating element.

[0039] The heating element can have at least two conductive contact regions. The conductive contact regions can be positioned at the end regions of the heating element.

[0040] At least two conductive contact regions are each preferably positioned in a dense region of the heating element. The conductive contact region can be positioned at the tip of the heating element. The conductive contact region may be directly fixed to the conductive filament. The conductive contact region may comprise a tin patch. Alternatively, the conductive contact region can be integral with the conductive filament.

[0041] According to a second aspect of the present invention, there is provided a cartridge for an aerosol generating system, comprising a heater assembly according to the first aspect of the present invention, a liquid storage portion for storing a liquid aerosol-forming substrate, and a holder for holding components of the heater assembly and maintaining a state in which the heater assembly is in contact with the liquid storage portion.

[0042] The cartridge preferably comprises a mouthpiece for holding the liquid storage portion.

[0043] The host material piece is preferably disposed in the internal space of the hollow body of the cap of the heater assembly. The transport material piece can be disposed in the holder opening of the holder that covers the first cap opening. The cap functions as a rigid housing for the transport material piece and the host material piece. The holder maintains contact between the heater assembly and the liquid storage portion via the transport material piece and the host material piece. The proximal end of the wall of the cap is preferably adjacent to the holder, and the distal end of the wall of the cap engages with the liquid storage portion.

[0044] The cartridge may be a disposable article, whereby it can be replaced with a new cartridge when the liquid storage portion of the cartridge becomes empty or falls below a minimum volume threshold. The cartridge is preferably pre-filled with a liquid aerosol-forming substrate. The cartridge can be refillable.

[0045] The cartridge and its components may be made of a thermoplastic polymer such as polyetheretherketone (PEEK).

[0046] According to a third aspect of the present invention, there is provided an aerosol generating system comprising a main unit and a cartridge according to the second aspect of the present invention, the cartridge being removably coupled to the main unit.

[0047] The aerosol generating system may be an electrically operated smoking system.

[0048] As used herein, the term that the cartridge is "removably coupled" to the main unit means that the cartridge and the main unit can be coupled and separated from each other without significantly damaging either the main unit or the cartridge.

[0049] The aerosol generating system may further comprise a heater assembly and an electrical circuit connected to a power source, the electrical circuit being configured to monitor the electrical resistance of the heater assembly or one or more filaments of the heater assembly and to control the power supply to the heater assembly depending on the electrical resistance of the heater assembly or one or more filaments.

[0050] The electrical circuit may comprise a microprocessor, which may be a programmable microprocessor. The electrical circuit may comprise further electronic components. The electrical circuit may be configured to regulate the power supply to the heater assembly. The power may be continuously supplied to the heater assembly after activation of the system, or may be supplied intermittently (e.g., each time an inhalation is made). The power may be supplied to the heater assembly in the form of current pulses.

[0051] The aerosol generating system advantageously typically comprises a power source, such as a battery, within the housing of the main body. Alternatively, the power source may be another form of charge storage device, such as a capacitor. The power source may need to be recharged and may have a capacity that allows for sufficient energy storage for one or more smoking experiences. For example, the power source may have a capacity sufficient to allow for continuous generation of aerosol for about 6 minutes, or a multiple of 6 minutes. In another embodiment, the power source may have a capacity sufficient to enable a predetermined number of puffs or discontinuous activation of the heater assembly.

[0052] The aerosol generating system preferably includes a housing. The housing is preferably elongated. The housing may comprise any suitable material or combination of materials. Examples of suitable materials include metals, alloys, plastics, or composite materials containing one or more of these materials, or thermoplastic resins suitable for food or pharmaceutical applications, such as polypropylene, polyetheretherketone (PEEK), and polyethylene. The material is preferably lightweight and not brittle.

[0053] The aerosol generating system is preferably portable. The aerosol generating system may be sized to rival a conventional cigar or cigarette. The overall length of the smoking system may be from approximately 30 millimeters to approximately 150 millimeters. The outer diameter of the smoking system may be from approximately 5 millimeters to approximately 30 millimeters.

[0054] The aerosol forming substrate is a substrate having the ability to release volatile compounds capable of forming an aerosol. The volatile compounds may be released by heating the aerosol forming substrate.

[0055] The aerosol-forming substrate may comprise a plant-derived material. The aerosol-forming substrate may comprise tobacco. The aerosol-forming substrate may comprise a tobacco-containing material containing volatile tobacco flavor compounds released from the aerosol-forming substrate upon heating. Alternatively, the aerosol-forming substrate may comprise a non-tobacco-containing material. The aerosol-forming substrate may comprise a homogenized plant-derived material. The aerosol-forming substrate may comprise a homogenized tobacco material. The aerosol-forming substrate may comprise at least one aerosol-forming body. The aerosol-forming substrate may comprise other additives and components (such as flavoring agents).

[0056] According to a fourth aspect of the present invention, there is provided a method for manufacturing a fluid-permeable heater assembly according to the first aspect, the method comprising the steps of providing a substantially planar electrically conductive heating element and forming a cap at an end region on one side surface of the heating element, the cap comprising a hollow body having first and second cap openings, the first cap opening facing the second cap opening, and the heating element being mounted on the cap such that the heating element extends across the first cap opening.

[0057] The step of providing the heating element may include providing a mesh strip, which may include mesh sections in an alternating sequence of a first mesh density and a second mesh density. Having a high-density section may increase the stability of the mesh during handling.

[0058] The step of providing the heating element may further include die-cutting chamfered window slots from each side of the mesh section of the first mesh density and removing relaxation lines from the cut-out mesh section of the first mesh density.

[0059] Preferably, the first mesh density is lower than the second mesh density.

[0060] The step of forming a cap in an end region of one side portion of the heating element preferably includes preheating plastic granules, injecting the plastic granules into a mold to form a cap, and forming the cap under a mesh section having a second mesh density.

[0061] The step of forming a cap in an end region of one side portion of the heating element preferably further includes cutting a mesh strip from the heater assembly and removing debris from the heater assembly.

[0062] The step of cutting a mesh strip from the heater assembly includes die-cutting the mesh strip from the mesh. The heating element includes a mesh, and the mesh preferably has a mesh section of a first mesh density that is limited by mesh sections of a second mesh density on each of two ends of the mesh from which the mesh is cut, and is cut within the mesh section of the second mesh density.

[0063] The method for manufacturing a fluid-permeable heater assembly according to the first aspect of the present invention preferably further includes coupling at least two conductive contact regions respectively on an end region of the other side surface of the heating element.

[0064] The step of coupling at least two conductive contact regions respectively on an end region of the other side surface of the heating element may include providing a strip of tin foil, cutting a tin foil patch from the strip of tin foil to a size that fits the shape and size of the mesh section having a second mesh density, and pressing the tin foil patch onto the mesh section having the second mesh density. It may be advantageous for the strip of foil to be made of a material that softens more than the material of the heating element.

[0065] The method for manufacturing a fluid-permeable heater assembly according to the first aspect of the present invention preferably further includes inspecting the heater assembly.

[0066] The process of inspecting the heater assembly includes transporting the heater assembly to an inspection station, measuring the electrical resistance of the heating element of the manufactured heater assembly, visually inspecting the heating element for accurate wire count, clean cut-out portions of the mesh, accurate mesh integrity, fragments, and solder foil attachment, and rejecting the heater assembly if it fails to meet at least one of the expected electrical resistance of the heating element and the expected results of the visual inspection.

[0067] According to a fifth aspect of the present invention, there is provided an apparatus for manufacturing a fluid-permeable heater assembly according to the fourth aspect.

[0068] To manufacture a heater assembly having a substantially planar conductive heating element with a cap and a mesh, the apparatus for manufacturing a fluid-permeable heater assembly can comprise at least one of the following apparatus units.

[0069] - A mesh strip bobbin supply unit for providing mesh strips, the mesh strips including mesh sections in an alternating sequence of a first mesh density and a second mesh density, the mesh strip bobbin supply unit - A solder foil strip bobbin supply unit for providing solder foil strips - A solder foil cutting station for determining the length of the solder foil and positioning it on the mesh section of the second mesh density and cutting solder patches from the provided solder foil strips - A solder foil pressing station for pressing and joining the solder patches onto the upper surface of the mesh section of the second mesh density - A mesh window cutting station for die-cutting chamfered window grooves from each side of the mesh section of the first mesh density - A first cleaning station for removing slack lines, small particles, dust, or debris from a cut mesh section of a first mesh density by cleaning using air pressure and sweeping the surface of the cut mesh section with a vacuum cleaner. - An injection molding machine for preheating plastic granules and injecting the same into a mold to form a cap. - A mesh injection molding tool (having a single recess or several recesses if possible) for molding a cap under a mesh section of a second mesh density. - A heater assembly cutting station for cutting mesh strips from a heater assembly by die-cutting the mesh strips from the mesh, wherein the heating element comprises a mesh, and the mesh is cut within a mesh section of a second mesh density so that the mesh is limited by mesh sections of a second mesh density at two respective ends of the mesh from which the mesh is cut, and the mesh section of the first mesh density is provided. - A second cleaning station for removing slack lines from the mesh by cleaning using air pressure and sweeping the surface of the heater assembly with a vacuum cleaner to remove debris. - A moving unit for transporting the heater assembly to a heater assembly inspection station, wherein the heater assembly inspection station may include a heater assembly resistance measurement station, a heater assembly visual inspection station, and a heater assembly rejection station. - A mesh condition pressure test station. - A heater assembly resistance measurement station for measuring the electrical resistance of the mesh of the manufactured heater assembly and the electrical resistance of the tin foil strips. - A heater assembly visual inspection for visually inspecting the heater assembly, and - A heater assembly rejection station for rejecting heater assemblies that do not meet the specifications.

[0070] In a preferred manufacturing process, the apparatus automatically manufactures heater assemblies from mesh strips, and tin foil strips, and from plastic granules. The heater assembly comprises a cap and a substantially planar conductive heating element.

[0071] A preferred manufacturing process according to a fourth aspect of the present invention may include a manual loading of at least one of a mesh strip bobbin, a tin foil strip bobbin, and plastic granules. The preferred manufacturing process may further include at least one of the following method steps automatically performed by a manufacturing apparatus.

[0072] - Providing mesh strips, the mesh strips including mesh sections in an alternating sequence of a first mesh density and a second mesh density, - Providing tin foil strips, - Determining the length of the tin foil and positioning it across a mesh section of the second mesh density, - Cutting tin patches from the provided tin foil strips, - Pressing and joining the tin patches onto the upper surface of a mesh section of the second mesh density, - Die-cutting chamfered window grooves from each side of a mesh section of the first mesh density, - Removing slack lines, small particles, dust or debris from the cut mesh section of the first mesh density by cleaning with air pressure and sweeping the surface of the cut mesh section with a vacuum cleaner to remove debris, - Preheating the plastic granules, - Injecting the plastic granules into a mold to form a cap, - Molding a cap under a mesh section of the second mesh density, - Cutting mesh strips from the mesh to cut mesh strips from the heater assembly, wherein the heating element comprises a mesh, and the mesh is cut within a mesh section of a second mesh density, which is bounded by mesh sections of a first mesh density at two respective ends of the mesh from which the mesh has been cut. - Removing slack wires, small particles, dust or debris from the mesh by cleaning using air pressure and sweeping the surface of the mesh with a vacuum cleaner to remove debris. - Transporting the heater assembly to an inspection station. - Measuring the electrical resistance of the mesh of the manufactured heater assembly. - Visually inspecting the heater assembly for accurate wire count, clean cut-out portions of the mesh, accurate mesh integrity, debris, and solder foil attachment, and - Rejecting the heater assembly if it is out of specification.

[0073] Features described with respect to one aspect may equally apply to other aspects of the invention.

[0074] Embodiments of the present invention will now be described by way of illustration only with reference to the following accompanying drawings.

Brief Description of the Drawings

[0075]

Figure 1A

Figure 1B

Figure 1C

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

DETAILED DESCRIPTION OF THE INVENTION

[0076] FIG. 1A shows a heater assembly 10 including a cap 12 having a first cap opening 16 on the upper surface of the cap and a second cap opening 18 on the lower surface of the cap 12. The first cap opening 16 is covered by a holder 28 having a holder opening 30. The heater assembly 10 further includes a heating element 20 extending across the holder opening 30.

[0077] FIG. 1B shows the heating assembly 10 viewed from below. The internal space of the hollow body 14 of the cap 12 is visible.

[0078] FIG. 1C shows the components of the heating element 20 including a mesh 32. The mesh 32 has a first mesh section 44 of a first mesh density and a second mesh section 46 of a second mesh density above each of its two ends, and the second mesh density is higher than the first density. The tin foil patches 50 are joined to each of the two mesh sections 46 of the second mesh density. Each heating element 20 of the mesh 32 is disposed across the holder opening 30 of the holder 28 on the upper surface of the cap 12. The entire mesh section 44 of the first mesh density is disposed above the holder opening 30.

[0079] Figure 2 shows the cap 12 and its holder 28. The holder 28 may be a separate component. Preferably, the holder 28 is an integral part of the cap 12. The inner body of the hollow body 14 of the cap 12 has a cylindrical shape. The cuts A-A and B-B in Figure 2 show the cap 12 and its integrally formed holder 28, and the perspective view of Figure 2 shows the holder 28 as an individual component. The cuts A-A and B-B in Figure 2 show the first cap opening 16, where the smaller portion (referred to as the holder opening 30) remains open and the heating element can extend across it, and is partially closed by the holder 28.

[0080] Figure 3 shows the holder 28 formed as an individual component of the cap 12, where the heating element 20 is attached such that the mesh section 44 of the first mesh density extends across the holder opening 30.

[0081] Figure 4 shows the mesh 32 of the heating element 20. The mesh 32 includes a first mesh section 44 of the first mesh density and a second mesh section 46 of the second mesh density on each of its two tips.

[0082] Figure 5 shows the mesh strip 42 from which several meshes 32 can be die-cut.

[0083] FIG. 6 shows a cartridge 40 according to an embodiment of the present invention. The cartridge 40 includes a heater assembly 10 having a cap 12, and a heating element 20 disposed on a holder 28 of the cap 12. A transport material piece 26 is disposed in a holder opening 30 of the holder 28. A host material piece 24 is disposed in an internal space of a hollow body 14 of the cap 12. The cap 12 functions as a rigid housing for the transport material piece 26 and the host material piece 24. The cartridge 40 further includes a liquid storage portion for storing a liquid aerosol forming substrate. A retainer 42 is used to hold components of the heater assembly 10 and to hold the heater assembly 10 in contact with the liquid storage portion 36 via the transport material piece 26 and the host material piece 24. Further, the cartridge 40 includes a mouthpiece 38 in which the liquid storage portion 36 is disposed.

[0084] The above exemplary embodiments are illustrative but not limiting. In light of the above exemplary embodiments discussed above, other embodiments consistent with the above exemplary embodiments will be apparent to those skilled in the art.

Claims

1. A fluid-permeable heater assembly (10) for an aerosol generation system, comprising: a cap (12) having a hollow body (14) with first (16) and second (18) cap openings, the first cap opening (16) facing the second cap opening (18); a cap; a substantially planar, conductive, fluid-permeable heating element (20) configured to evaporate an aerosol-forming substrate (22), the heating element (20) being attached to the cap (12) such that the heating element (20) extends across the first cap opening (16); a fluid-permeable heating element; a host material piece (24) configured to hold a liquid aerosol-forming substrate (22), at least a portion of the host material piece (24) being disposed within the hollow body (14) between the first (16) and second (18) cap openings, the host material piece (24) being provided in at least partial contact with the heating element (20). A heater assembly.

2. The heater assembly (10) according to claim 1, wherein the host material piece (24) has substantially the same size and shape as the internal space of the hollow body (14).

3. The heater assembly (10) according to claim 1, wherein the internal space of the hollow body (14) is substantially cylindrical.

4. A transport material piece (26) configured to transport a liquid aerosol-forming substrate (22) from the host material piece (24) to the heating element (20), the transport material piece (26) being provided in contact with the heating element (20) and disposed between the heating element (20) and the host material piece (24). The heater assembly (10) according to claim 1, further comprising a transport material piece.

5. The heater assembly (10) according to claim 4, wherein the cap (12) further comprises a holder (28) having a holder opening (30), the holder (28) covering the first cap opening (16) such that the holder opening (30) coincides with at least a portion of the first cap opening (16), and the heating element (20) being attached onto the holder (28).

6. The heater assembly (10) according to claim 5, wherein the cap (12) is integrally formed.

7. The heater assembly (10) according to claim 5 or 6, wherein the transport material sheet (26) is disposed in the holder opening (30).

8. The heater assembly (10) according to any one of claims 5 to 7, wherein the transport material sheet (26) has substantially the same size and shape as the holder opening (30).

9. The heater assembly (10) according to any one of claims 1 to 8, comprising a mesh (32), wherein the heating element (20) has at least two conductive contact regions (34) respectively positioned at end regions of the heating element (20), and the mesh (32) extends across at least a portion of the first cap opening (16).

10. The heater assembly (10) according to claim 9, wherein each of the at least two conductive contact regions (34) is positioned in a dense region of the heating element (20).

11. A cartridge (40) for an aerosol generating system, the cartridge (40) comprising the heater assembly (10) according to any one of claims 1 to 10, a liquid storage portion (36) for storing a liquid aerosol forming substrate (22), and a holder (42) for holding the components of the heater assembly (10) and for maintaining contact between the heater assembly (10) and the liquid storage portion (36).

12. The cartridge (40) according to claim 11, further comprising a mouthpiece (38) for holding the liquid storage portion (36).

13. An aerosol generating system comprising a main unit and the cartridge (40) according to claim 11 or 12, wherein the cartridge (40) is removably coupled to the main unit.

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