CARTRIDGE FOR AEROSOL GENERATION SYSTEM AND AEROSOL GENERATION SYSTEM WITH IMPROVED LIQUID DELIVERY - Patent application

Abstract

A cartridge (100) for an aerosol generating system comprises a housing (105) enclosing a reservoir of liquid aerosol-forming substrate, a heating element (120) having a contact surface, and a compressible wicking element (136) positioned in contact with the contact surface of the heating element (120) and in communication with the liquid aerosol-forming substrate in the reservoir. The cartridge (100) comprises press elements (141, 142), the wicking element (136) positioned between the press elements (141, 142) and the heating element (120). The press elements (141, 142) press the wicking element (136) to urge it into contact with the contact surface of the heating element (120). This may result in more consistent liquid delivery across the heating element (120) and more consistent aerosol generation.

Description

[Technical field]

[0001] The present disclosure relates to an aerosol generating system that generates an aerosol by heating a liquid aerosol-forming substrate. The present disclosure also relates to a cartridge for such an aerosol generating system and the assembly of such a cartridge. [Background technology]

[0002] Aerosol generating systems that heat a liquid to generate an aerosol are well known. These systems typically use a wicking element to deliver the liquid to a heating element. The liquid in the wicking element is vaporized, and the generated vapor is then cooled to form an aerosol. To provide a consistent and sufficient generation of aerosol, it is necessary to ensure that there is a consistent and sufficient delivery of liquid to the heating element. Inconsistent liquid delivery to the heating element can result in a poor experience for the user.

[0003] One important factor for consistent liquid delivery to the heating element is the contact between the heating element and the wicking element. If the wicking element is intended to contact the heating element over an extended area, the delivery of liquid over that area may be inconsistent due to inconsistent contact between the heating element and the wicking element. Another important factor for consistent liquid delivery is consistent capillary action across the wicking material.

[0004] It is desirable to mitigate factors that lead to inconsistent or insufficient delivery of liquid aerosol-forming substrate through a wicking element to a heating element. Summary of the Invention

[0005] In one aspect of the disclosure, a cartridge for an aerosol generating system is provided. The cartridge may comprise a housing enclosing a reservoir of liquid aerosol-forming substrate, a heating element having a contact surface, and a compressible wicking element positioned in contact with the contact surface of the heating element and in communication with the liquid aerosol-forming substrate in the reservoir. The cartridge may comprise a press element, the wicking element being positioned between the press element and the heating element. The press element may press the wicking element to urge the wicking element into contact with the contact surface of the heating element.

[0006] The provision of a press element can provide a consistent contact area between the heating element and the wicking element from one cartridge to another. Any variation in the dimensions or orientation of the wicking element or heating element due to manufacturing tolerances can be at least partially mitigated by the provision of a press element. This can result in more consistent liquid delivery across the heating element, and therefore more consistent aerosol generation. Also, dry conditions at the heating element, which can lead to overheating and the formation of undesirable aerosol components, can be avoided.

[0007] The wicking element may be positioned in constant contact with the contact surface of the heating element.

[0008] The wicking element may have a front surface in contact with the contact surface of the heating element and a rear surface in contact with the press element. The rear surface may have a periphery and a central region facing inwardly of the periphery. The press element may contact the rear surface at a central region spaced inwardly from the periphery of the rear surface.

[0009] The periphery of the rear surface surrounds a central region of the rear surface. For example, in embodiments where the rear surface has a circular shape, the periphery may be an outer annular region that surrounds the circular central region. In embodiments where the rear surface is rectangular, the central region may be a central rectangle and the periphery may be an outer frame around the central region. The central region may have the same aspect ratio as the rear surface.

[0010] The diameter or width of the posterior surface along an axis may have a length D. The extent of the central region along the axis may have a length C, and the peripheral extents along that axis may have a length P on either side of the central region, such that D=C+2P. The value of P may be between 0.05D and 0.4D, or between 0.1D and 0.2D, as measured along any axis in the plane of the posterior surface.

[0011] Pressing the wicking element in the central region may have the advantage of improving the uniformity of capillarity of the wicking element. In some embodiments, the periphery of the wicking element may be compressed more than the central region during the manufacturing process of the wicking element. This may be an unavoidable result of the manufacturing process, e.g. the punching process. Advantageously, a pressing element is provided such that the wicking element is compressed to a greater extent in the central region than at the periphery of the rear surface. Advantageously, the periphery of the rear surface of the wicking element may not be compressed in the cartridge. This may improve the uniformity of liquid delivery through the wicking element.

[0012] In some embodiments, the wicking element has a greater thickness in the central region than at the periphery. Thickness in this context is the dimension in the direction of liquid movement from the rear surface to the front surface of the wicking element. The front surface of the wicking element may be domed to provide a greater thickness in the central region than at the periphery. In these embodiments, a press element may be provided such that the wicking element is compressed to a greater extent in the central region than at the periphery of the rear surface. This may improve the uniformity of liquid delivery to the front surface of the wicking element.

[0013] In an uncompressed state, the wicking element may have a greater porosity in the central region than in the periphery, and in a compressed state, when the central region is compressed to a greater extent than the periphery, the porosity of the central region may be substantially equal to the porosity of the periphery, thereby providing a substantially uniform liquid delivery rate across the front surface of the wicking element.

[0014] The wicking element may have a circular cross-section in a plane parallel to the contact surface. A circular cross-section may advantageously reduce the requirement for correct orientation of the wicking element. The wicking element may have a rectangular cross-section in a plane parallel to the contact surface. The wicking element may have a regular polygonal cross-section in a plane parallel to the contact surface. The wicking element may have an elliptical cross-section in a plane parallel to the contact surface. The wicking element may be disc-shaped.

[0015] The wicking element may include a fibrous material or a sponge-like material. The wicking element may include a bundle of capillaries. For example, the wicking element may include one or more of fibers, threads, and pore tubes. The wicking element may include a sponge-like or foam-like material. The structure of the wicking element may form a plurality of small holes or tubes through which liquid can be transported by capillary action. The wicking element may include an open-pore structure. The wicking element may include any suitable material or combination of materials. The wicking element may include pressed cotton. Other suitable materials include, for example, but are not limited to, fibrous materials made of spun or extruded fibers, such as cellulose acetate, polyester, or bonded polyolefin, polyethylene, terylene, or polypropylene fibers, or nylon fibers. The wicking element may include layers of multiple different materials.

[0016] In one embodiment, the wicking element is formed from cotton fibers that are physically bonded together in a continuous flow manufacturing process. A mechanical puncher is used to impart the required shape for the wicking element to the wicking material.

[0017] The liquid aerosol-forming substrate is preferably absorbed within the wicking element. The element may be configured or may store at least 0.02, 0.05, 0.1, 0.2, or 0.5 ml of the liquid aerosol-forming substrate. The wicking element may be configured or may store no more than 2 ml or 5 ml of the liquid aerosol-forming substrate.

[0018] The liquid aerosol-forming substrate from the reservoir may pass through the press element to reach the wicking element. The liquid aerosol-forming substrate from the reservoir may pass through the press element to reach the wicking element in a direction in which the press element presses against the wicking element.

[0019] The press element may be configured to allow liquid to pass through the press element in a direction perpendicular to the rear surface of the wicking element.

[0020] The press element may be liquid permeable. In this context, liquid permeable means that liquid may penetrate through the pores or openings of the press element. The press element may include a mesh, net, or lattice structure.

[0021] The press element may comprise a hollow press member through which the liquid aerosol-forming substrate from the reservoir can pass to reach the wicking material. The press element may comprise one or more pins, tabs, or tubes. The press element may provide multiple distinct points of contact with the wicking element. The press element may comprise a continuous closed loop that contacts the wicking element.

[0022] The press element may be stiffer than the wicking element so as to provide a compressive force to the wicking element. The heating element may also be stiffer than the wicking element.

[0023] The press element, or a portion of the press element, may be integral with the housing. The press element, or a portion of the press element, may be separate from the housing. The press element may be located between the housing and the wicking element. The press element may be fixed relative to the heating element.

[0024] The press element may include a convex surface that contacts the rear surface of the wicking element. The convex shape of the press element may match the dome-shaped front surface of the wicking element. The press element may have a press surface that has a smaller area than the rear surface of the wicking element. In particular, the press surface may not contact the periphery of the rear surface of the wicking element. This means that the periphery of the wicking element is not compressed by the press element. Advantageously, the press element may provide a substantially uniform porosity within the wicking element when the wicking element is pressed by the press element.

[0025] The heating element may be fluid permeable. The heating element may comprise a mesh. The heating element may be a mesh heating element. The heating element may be a perforated heating element. The mesh or perforated heating element may provide an extended heating surface area. This extended heating surface area may provide efficient vaporization of the aerosol-forming substrate.

[0026] The heating element may be secured to the housing. The heating element may include electrical contacts for connection to an external power source. The heating element may be configured to be resistively heated. The heating element may be configured to be inductively heated. The heating element may include a susceptor configured to be inductively heated. The heating element may be configured to vaporize the liquid aerosol-forming substrate.

[0027] The heating element may be planar. The heating element may be in the form of a sheet. The heating element may have a thickness that is an order of magnitude or more smaller than the width, length or diameter of the heating element.

[0028] The area of ​​the heating element (perpendicular to the thickness) may be, for example, 50 square millimeters or less, preferably 25 square millimeters or less, and more preferably about 15 square millimeters. The size is chosen to allow the heating element to be incorporated into a handheld system. Sizing the heating element to 50 square millimeters or less reduces the total amount of power required to heat the heating element while still ensuring sufficient contact between the heating element and the wicking element. The heating element 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.

[0029] The heating element, or portions thereof, may include or be formed from any material having suitable electrical and mechanical properties, for example, a suitable electrically resistive material. 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 composites made of ceramic and metallic materials. Such composites may include doped or undoped ceramics. Examples of suitable doped ceramics include doped silicon carbide. Examples of suitable metals include titanium, zirconium, tantalum, and platinum group metals. Examples of suitable 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, iron-aluminum-based alloys, and iron-manganese-aluminum-based alloys.

[0030] As used herein, the term "aerosol" refers to a dispersion of solid particles, or liquid droplets, or a combination of solid particles and liquid droplets in a gas. Aerosols may be visible or invisible. Aerosols may include not only vapors of substances that are normally liquids or solids at room temperature, but also solid particles or liquid droplets, or a combination of solid particles and liquid droplets.

[0031] As used herein with respect to the present invention, an aerosol-forming substrate is a substrate capable of releasing a volatile compound capable of forming an aerosol. The volatile compound may be released by heating or burning the aerosol-forming substrate. The volatile compound may be released by moving the aerosol-forming substrate through the passage of a vibrable element. The aerosol-forming substrate may include both liquid and solid components.

[0032] The aerosol-forming substrate may include one or more aerosol formers. The aerosol former is any suitable known compound or mixture of compounds that facilitates the formation of a dense, stable aerosol during use and is substantially resistant to thermal decomposition at the operating temperature of the system. Examples of suitable aerosol formers include glycerin and propylene glycol. Suitable aerosol formers are well known in the art and include, but are not limited to, polyhydric alcohols (such as triethylene glycol, 1,3-butanediol, glycerin), esters of polyhydric alcohols (such as glycerol monoacetate, diacetate, or triacetate), and aliphatic esters of mono-, di-, or polycarboxylic acids (such as dimethyl dodecanedioate, dimethyl tetradecanedioate, etc.). The liquid aerosol-forming substrate may include water, solvents, ethanol, plant extracts, and natural or artificial flavors. The liquid aerosol-forming substrate may include nicotine and at least one aerosol former. The aerosol former may be glycerin or propylene glycol. The aerosol former may include both glycerin and propylene glycol. The liquid aerosol-forming substrate may have a nicotine concentration of about 0.5% to about 10%, for example about 2%.

[0033] The aerosol-forming substrate may comprise nicotine. The nicotine-containing aerosol-forming substrate may be a nicotine salt matrix. The liquid 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 flavour compounds which are released from the aerosol-forming substrate upon heating. The aerosol-forming substrate may comprise a homogenised tobacco material. The aerosol-forming substrate may comprise a non-tobacco-containing material. The aerosol-forming substrate may comprise a homogenised plant-derived material. The aerosol-forming substrate may comprise other additives and ingredients such as flavourants.

[0034] As used herein, the term "liquid aerosol-forming substrate" is used to refer to an aerosol-forming substrate in a condensed form. Thus, a "liquid aerosol-forming substrate" may be or include one or more of a liquid, a gel, or a paste. When the liquid aerosol-forming substrate is or includes a gel or paste, the gel or paste may liquefy upon heating. For example, the gel or paste may liquefy upon heating to a temperature of less than 50, 75, 100, 150, or 200 degrees Celsius.

[0035] The cartridge may further comprise an air inlet, an air outlet, and an airflow path from the air inlet to the air outlet. The airflow path may pass through the heating element. The heating element may have a second surface opposite the contact surface. The second surface may be within the airflow path. The cartridge may further comprise a mouthpiece configured to enable a user to apply negative pressure to the mouthpiece and draw air through the airflow path.

[0036] The cartridge may be configured to connect to a reusable device. The device may comprise a power source and control electronics. When the aerosol-forming substrate is depleted, the cartridge can be replaced and a new cartridge can be used with the reusable device.

[0037] In another aspect of the present disclosure, an aerosol generation system is provided.

[0038] The aerosol generation system may be provided as a single component system. a housing enclosing a reservoir of liquid aerosol-forming substrate; a heating element fixed to the housing; a compressible wicking element positioned in contact with a surface of the heating element and in communication with the liquid in the reservoir; The wicking material may include a press element, the press element being positioned between the press element and the heating element, the press element pressing against the wicking element to urge the wicking material into contact with a surface of the heating element.

[0039] The features of the wicking element, press element, heating element and aerosol-forming substrate described in relation to the first aspect of the present disclosure also apply to this aspect of the present disclosure.

[0040] The aerosol generation system may further comprise an air inlet, an air outlet, and an airflow path from the air inlet to the air outlet.

[0041] The heating element may be configured to be activated by airflow through the airflow path. The aerosol generation system may further comprise an airflow sensor. The airflow sensor may be configured to detect airflow through the airflow path. The airflow sensor may be configured to activate the heating element. The aerosol generation system may further comprise a mouthpiece configured to enable a user to apply negative pressure to the mouthpiece and draw air through the airflow path.

[0042] The aerosol generation system may further comprise a power source. The power source may be a battery. The power source may be configured to provide power to the heating element. The aerosol generation system may comprise control electronics. The power source may be configured to provide power to the heating element via the control electronics.

[0043] An aerosol generation system may comprise a cartridge according to an aspect of the invention. The aerosol generation system may comprise a reusable device. The cartridge may be configured to engage with the reusable device. The cartridge may be configured to disengage from the reusable device. The reusable device may be configured to engage and disengage with the cartridge via a snap-fit ​​connection, corresponding threads, or any other suitable means. The reusable device may comprise a chamber configured to receive at least a portion of the cartridge. The reusable device may include an air inlet. The reusable device may include an air outlet. When the reusable device is engaged with the cartridge, the air outlet of the reusable device may be in fluid communication with the air inlet of the cartridge.

[0044] The reusable device may include a power source. The power source may be a battery. The power source may be configured to provide power to the heating element. The power source may be configured to provide power to the heating element only when the cartridge is engaged with the reusable device. The power source may be electrically connected to device electrical contacts of the reusable device. These device electrical contacts may be configured to form an electrical connection with corresponding electrical contacts on the cartridge when the cartridge is engaged with the reusable device. The reusable device may include electrical control electronics. The power source may be configured to provide power to the heating element via the control electronics.

[0045] In yet a further aspect of the present disclosure, there is provided a method of assembling a cartridge for an aerosol generation system, comprising the steps of: providing a housing for enclosing a reservoir of liquid aerosol-forming substrate; providing a heating element having a contact surface; Providing a compressible wicking element; pressing the wicking element against the contact surface using a press element, the wicking element being positioned between the press element and the heating element; A method is provided that includes providing a liquid aerosol-forming substrate within a housing, the liquid aerosol-forming substrate within the housing being in fluid communication with a wicking element.

[0046] The features of the wicking element, press element, heating element and aerosol-forming substrate described in relation to the first aspect of the present disclosure also apply to this aspect of the present disclosure.

[0047] In yet a further aspect of the present disclosure, there is provided a method of generating an aerosol, comprising: Providing a heating element; providing a wicking element in contact with the heating element, the wicking element comprising a liquid aerosol-forming substrate; Pressing the wicking element against the heating element; heating the heating element to vaporize the liquid aerosol-forming substrate; and cooling the vapor in the airflow to form an aerosol.

[0048] The features of the wicking element, press element, heating element and aerosol-forming substrate described in relation to the first aspect of the present disclosure also apply to this aspect of the present disclosure. EXAMPLES

[0049] The following non-limiting examples are provided in a non-exhaustive manner, any one or more of the features of these examples may be combined with any one or more features of other examples, embodiments, or aspects described herein.

[0050] Example 1. 1. A cartridge for an aerosol generation system, the cartridge comprising: a housing enclosing a reservoir of liquid aerosol-forming substrate; a heating element having a contact surface; a compressible wicking element positioned in contact with the contact surface of the heating element and in communication with the liquid aerosol-forming substrate within the reservoir; A cartridge comprising: a press element, the wicking element being positioned between the press element and the heating element, the press element pressing the wicking element to urge the wicking element into contact with a contact surface of the heating element. Example 2. A cartridge according to example 1, wherein the wicking element has a front surface in contact with the contact surface of the heating element and a rear surface in contact with the press element, the press element contacting the rear surface in a central region spaced inwardly from the periphery of the rear surface. Example 3. A cartridge according to example 1 or 2, wherein the wicking element is not pressed around the periphery of the rear face. Example 4. A cartridge according to example 2, wherein a pressing element is provided such that the wicking element is compressed to a greater extent in the central region than in the periphery of the rear face. Example 5. A cartridge according to any one of Examples 2-4, wherein the wicking element has a greater thickness in the central region than at the periphery. Example 6. A cartridge according to any one of Examples 2-5, wherein in an uncompressed state, the wicking element has a greater porosity in the central region than in the periphery. Example 7. A cartridge according to any one of Examples 1 to 6, wherein the front surface of the wicking element is dome-shaped. Example 8. A cartridge according to any one of Examples 1 to 7, wherein the wicking element has a circular cross section in a plane parallel to the contact surface. Example 9. The cartridge according to any one of the preceding claims, wherein the wicking element comprises a fibrous or spongy material. Example 10. The cartridge according to any one of Examples 1-9, wherein the wicking element comprises pressed cotton. Example 11. The cartridge according to any one of Examples 1 to 10, wherein the wicking element comprises a plurality of layers of different materials. Example 12. A cartridge according to any one of the preceding claims, wherein the pressing element is liquid permeable. Example 13. A cartridge according to any one of Examples 1 to 12, wherein the pressing element comprises a hollow pressing member through which the liquid aerosol-forming substrate from the reservoir can pass to reach the wicking material. Example 14. The cartridge according to any one of the preceding embodiments, wherein the pressing element is integral with the housing. Example 15. The cartridge according to any one of Examples 1 to 13, wherein the pressing element is positioned between the housing and the wicking element. Example 16. The cartridge according to any one of embodiments 1 to 15, wherein the pressing element is harder than the wicking element. Example 17. The cartridge according to any one of the preceding claims, wherein the pressing element comprises one or more pins, tabs, or tubes. Example 18. The cartridge according to any one of the preceding claims, wherein the pressing element comprises a mesh, net, or lattice structure. Example 19. The cartridge according to any one of Examples 1 to 18, wherein the heating element is fluid permeable. Example 20. The cartridge according to any one of Examples 1 to 19, wherein the heating element is planar. Example 21. The cartridge according to any one of Examples 1 to 20, wherein the heating element comprises a mesh. Example 22. The cartridge according to any one of Examples 1 to 21, wherein the heating element is fixed to the housing. Example 23. The cartridge according to any one of Examples 1-22, wherein the pressing element provides a uniform porosity within the wicking element when the wicking element is pressed. Example 24. A cartridge according to any one of Examples 1 to 23, wherein the heating element includes electrical contacts for connecting to an external power source. Example 25. A cartridge according to any one of Examples 1 to 24, comprising a susceptor configured such that the heating element inductively heats and vaporizes the liquid aerosol-forming substrate. Example 26. The cartridge according to any one of Examples 1-25, wherein the pressing element includes a convex surface that contacts the rear surface of the wicking element. Example 27. A cartridge according to Example 26, wherein the convex surface of the pressing element matches the dome shape of the front surface of the wicking element. Example 28. The cartridge according to any one of the preceding claims, wherein the pressing element has a pressing surface having a smaller diameter or width than the rear surface of the wicking element. Example 29. The cartridge according to any one of Examples 1 to 28, wherein the wicking element is disc-shaped. Example 30. The cartridge according to any one of Examples 1-29, wherein the wicking element comprises an annular hub and a plurality of protrusions connected to the hub. Example 31. A cartridge according to any one of embodiments 1 to 30, wherein the liquid aerosol-forming substrate from the reservoir can pass through the pressing element in a direction in which the pressing element presses the wicking element. Example 32. The cartridge according to any one of Examples 1-31, wherein the pressing element is configured to allow liquid to pass through the pressing element in a direction perpendicular to the rear surface of the wicking element. Example 33. 1. An aerosol generation system comprising: a housing enclosing a reservoir of liquid aerosol-forming substrate; a heating element fixed to the housing; a compressible wicking material positioned in contact with a surface of the heating element and in communication with the liquid in the reservoir; a press element, the wicking material being positioned between the press element and the heating element, the press element pressing the wicking material to urge the wicking material into contact with a surface of the heating element. Example 34. An aerosol generating system according to Example 33, wherein the wicking element has a front surface in contact with the contact surface of the heating element and a rear surface in contact with the press element, and the press element contacts the rear surface in a central region spaced inwardly from the periphery of the rear surface. Example 35. An aerosol generating system according to Examples 33 or 34, wherein the wicking element is not pressed around the periphery of the rear surface. Example 36. An aerosol generating system according to Example 35, wherein the pressing element is provided such that the wicking element is compressed to a greater extent in the central region than at the periphery of the rear surface. Example 37. An aerosol generation system according to any one of Examples 34 to 36, wherein the wicking element has a greater thickness in the central region than at the periphery. Example 38. An aerosol generation system according to any one of Examples 34-37, wherein in an uncompressed state, the wicking element has a greater porosity in the central region than at the periphery. Example 39. An aerosol generation system according to any one of Examples 33 to 38, wherein the front surface of the wicking element is dome-shaped. Example 40. An aerosol generation system according to any one of Examples 33 to 39, wherein the wicking element has a circular cross section in a plane parallel to the contact surface. Example 41. An aerosol generation system according to any one of Examples 33 to 40, wherein the wicking element comprises a fibrous or spongy structure. Example 42. An aerosol generation system according to any one of Examples 33-41, wherein the wicking element comprises pressed cotton. Example 43. An aerosol generation system according to any one of Examples 33-42, wherein the wicking element comprises multiple layers of different materials. Example 44. The aerosol generating system according to any one of Examples 33 to 43, wherein the press element is liquid permeable. Example 45. An aerosol generating system according to any one of Examples 33-44, wherein the pressing element comprises a hollow pressing member through which the liquid aerosol-forming substrate from the reservoir can pass to reach the wicking material. Example 46. An aerosol generating system according to any one of Examples 33 to 45, wherein the pressing element is integral with the housing. Example 47. An aerosol generation system according to any one of Examples 33-45, wherein the pressing element is positioned between the housing and the wicking element. Example 48. An aerosol generating system according to any one of Examples 33 to 47, wherein the pressing element is stiffer than the wicking element. Example 49. The aerosol generation system according to any one of Examples 33 to 48, wherein the pressing element comprises one or more pins, tabs, or tubes. Example 50. The aerosol generating system according to any one of Examples 33-49, wherein the press element comprises a mesh, net, or lattice structure. Example 51. The aerosol generating system according to any one of Examples 33 to 50, wherein the heating element is fluid permeable. Example 52. The aerosol generating system according to any one of Examples 33 to 51, wherein the heating element is planar. Example 53. The aerosol generating system according to any one of Examples 33 to 52, wherein the heating element comprises a mesh. Example 54. An aerosol generating system according to any one of Examples 33 to 53, wherein the heating element is fixed to the housing. Example 55. An aerosol generation system according to any one of Examples 33-54, wherein the pressing element provides a uniform porosity within the wicking element when the wicking element is pressed. Example 56. An aerosol generating system according to any one of Examples 33 to 55, comprising a susceptor configured such that the heating element inductively heats and vaporizes the liquid aerosol-forming substrate. Example 57. An aerosol generating system according to any one of Examples 33-56, wherein the pressing element comprises a convex surface in contact with the rear surface of the wicking element. Example 58. An aerosol generating system according to Example 57, wherein the convex surface of the pressing element matches the dome shape of the front surface of the wicking element. Example 59. An aerosol generation system according to any one of Examples 33 to 58, wherein the pressing element has a pressing surface having a smaller diameter or width than the rear surface of the wicking element. Example 60. An aerosol generation system according to any one of Examples 33 to 59, wherein the wicking element is disc-shaped. Example 61. An aerosol generation system according to any one of Examples 33-60, wherein the wicking element comprises an annular hub and a plurality of protrusions connected to the hub. Example 62. An aerosol-generating system according to any one of Examples 33-61, wherein the liquid aerosol-forming substrate from the reservoir can pass through the pressing element in a direction in which the pressing element presses the wicking element. Example 63. An aerosol generation system according to any one of Examples 33-62, wherein the pressing element is configured to allow liquid to pass through the pressing element in a direction perpendicular to the rear surface of the wicking element. Example 64. An aerosol generating system according to any one of Examples 33 to 63, comprising a power source for providing power to the heating element. Example 65. An aerosol generating system according to any one of Examples 33 to 64, comprising a control circuit for controlling the power supply to the heating element. Example 66. 1. A method of assembling a cartridge for an aerosol generation system, comprising: providing a housing for enclosing a reservoir of liquid aerosol-forming substrate; providing a heating element having a contact surface; Providing a compressible wicking element; Pressing the wicking element against the contact surface using a press element, pressing, wherein a wicking element is positioned between the press element and the heating element; providing a liquid aerosol-forming substrate within a housing, the liquid aerosol-forming substrate within the housing being in fluid communication with a wicking element. Example 67. A method according to example 66, wherein the wicking element has a front surface in contact with the contact surface of the heating element and a rear surface in contact with the press element, the press element contacting the rear surface in a central region spaced inwardly from the periphery of the rear surface. Example 68. The method according to embodiment 66 or 67, wherein the wicking element is not pressed around the periphery of the rear surface. Example 69. A method according to example 67, wherein a pressing element is provided such that the wicking element is compressed to a greater extent in the central region than in the periphery of the rear surface. Example 70. The method according to any one of Examples 67-69, wherein the wicking element has a greater thickness in the central region than in the periphery. Example 71. The method according to any one of Examples 67-70, wherein in an uncompressed state, the wicking element has a greater porosity in the central region than in the periphery. Example 72. The method according to any one of Examples 66-71, wherein the front surface of the wicking element is dome-shaped. Example 73. The method according to any one of embodiments 66-72, wherein the wicking element has a circular cross-section in a plane parallel to the contact surface. Example 74. The method according to any one of Examples 66-73, wherein the wicking element comprises a fibrous or spongy material. Example 75. The method according to any one of Examples 66-74, wherein the wicking element comprises pressed cotton. Example 76. The method according to any one of Examples 66-75, wherein the wicking element comprises multiple layers of different materials. Example 77. The method according to any one of Examples 66 to 76, wherein the press element is liquid permeable. Example 78. The method according to any one of examples 66-77, wherein the press element comprises a hollow press member through which the liquid aerosol-forming substrate from the reservoir can pass to reach the wicking material. Example 79. The method according to any one of embodiments 66-78, wherein the pressing element is integral with the housing. Example 80. The method according to any one of Examples 66-79, wherein the pressing element is positioned between the housing and the wicking element. Example 81. The method according to any one of embodiments 66-80, wherein the pressing element is stiffer than the wicking element. Example 82. The method according to any one of Examples 66-81, wherein the pressing element comprises one or more pins, tabs, or tubes. Example 83. The method according to any one of Examples 66-82, wherein the press element comprises a mesh, net, or lattice structure. Example 84. The method according to any one of Examples 66 to 83, wherein the heating element is fluid permeable. Example 85. The method according to any one of Examples 66 to 84, wherein the heating element is planar. Example 86. The method according to any one of Examples 66-85, wherein the heating element comprises a mesh. Example 87. The method according to any one of Examples 66 to 86, wherein the heating element is secured to the housing. Example 88. The method according to any one of Examples 66-87, wherein the pressing element provides a uniform porosity within the wicking element when the wicking element is pressed. Example 89. The method according to any one of Examples 66-88, wherein the heating element includes electrical contacts for connecting to an external power source. Example 90. The method according to any one of examples 66-89, wherein the heating element comprises a susceptor configured to inductively heat and vaporize the liquid aerosol-forming substrate. Example 91. The method according to any one of Examples 66-90, wherein the pressing element includes a convex surface in contact with the rear surface of the wicking element. Example 92. The method according to example 91, wherein the convex surface of the pressing element matches the dome shape of the front surface of the wicking element. Example 93. The method according to any one of embodiments 66-92, wherein the pressing element has a pressing surface having a smaller diameter or width than the rear surface of the wicking element. Example 94. The method according to any one of Examples 66-93, wherein the wicking element is disc-shaped. Example 95. The method according to any one of Examples 66-94, wherein the wicking element comprises an annular hub and a plurality of protrusions connected to the hub. Example 96. The method according to any one of embodiments 66-95, wherein the liquid aerosol-forming substrate from the reservoir is allowed to pass through the pressing element in a direction in which the pressing element presses the wicking element. Example 97. The method according to any one of examples 66-96, wherein the pressing element is configured to allow liquid to pass through the pressing element in a direction perpendicular to the rear surface of the wicking element. Example 98. 1. A method for generating an aerosol, comprising: Providing a heating element; providing a wicking element in contact with the heating element, the wicking element comprising a liquid aerosol-forming substrate; Pressing the wicking element against the heating element; heating the heating element to vaporize the liquid aerosol-forming substrate; and cooling the vapor in the airflow to form an aerosol. [Brief description of the drawings]

[0051] [Figure 1] FIG. 1 shows a schematic diagram of an aerosol generation system according to a first embodiment of the present disclosure. [Diagram 2] FIG. 2 is a schematic cross-section of a cartridge of an aerosol generation system of the type shown in FIG. [Diagram 3] FIG. 3 is a second schematic cross-section of the cartridge of FIG. [Figure 4] FIG. 4 illustrates possible cross-sectional shapes of the pressing element. [Diagram 5] FIG. 5 illustrates another possible configuration of the press element. [Figure 6] FIG. 6 is an exploded view of a cartridge of the type shown in FIG. [Figure 7]FIG. 7 is a cross-section of a wicking element for use in the cartridge of FIG. [Figure 8] FIG. 8 shows a cross section of a portion of the cartridge of FIG. 7 with a pressing element. [Figure 9A] FIG. 9A shows the press element of FIG. [Figure 9B] FIG. 9B shows the pressing element of FIG. [Figure 9C] FIG. 9C shows the pressing element of FIG. [Figure 10A] FIG. 10A shows an alternative press element. [Figure 10B] FIG. 10B shows an alternative press element. [Figure 11] FIG. 11 shows a further pressing element. [Figure 12] FIG. 12 is a schematic cross-section of a cartridge with an alternative pressing element. [Figure 13] FIG. 13 is a flow diagram of a method for assembling an aerosol generating system. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0052] The embodiments will now be further described with reference to the figures.

[0053] 1 is a schematic diagram of an aerosol generation system according to the present disclosure. The system comprises two main components: a cartridge 100 and a reusable device or control body 200. A connecting end 115 of the cartridge 100 is removably connected to a corresponding connecting end 205 of the control body 200. The control body 200 contains a battery 210, which in this embodiment is a rechargeable lithium-ion battery, and control electronics 220. The aerosol generation system is portable and has a size comparable to a conventional cigar or cigarette.

[0054] The cartridge 100 comprises a housing 105 containing a heater assembly 120 and a liquid storage compartment having a first portion 130 and a second portion 135. A liquid aerosol-forming substrate is held in the liquid storage compartment. Although not shown in FIG. 1 , the first portion 130 of the liquid storage compartment is connected to the second portion 135 of the liquid storage compartment such that liquid in the first portion 130 can travel to the second portion 135. The heater assembly 120 receives liquid from the second portion 135 of the liquid storage compartment. In this embodiment, the heater assembly 120 includes a generally planar, fluid-permeable heating element.

[0055] Airflow passages 140 , 145 extend through the cartridge 100 from the air inlet 150 past the heater assembly 120 and from the heater assembly 120 to a mouth end opening 110 in the cartridge housing 105 .

[0056] The components of the cartridge 100 are arranged such that a first portion 130 of the liquid storage compartment is between the heater assembly 120 and the mouth end opening 110, and a second portion 135 of the liquid storage compartment is positioned on the opposite side of the heater assembly 120 relative to the mouth end opening 110. In other words, the heater assembly 120 is between the two portions 130, 135 of the liquid storage compartment and receives liquid from the second portion 135, and the first portion 130 of the liquid storage compartment is closer to the mouth end opening 110 than the second portion 135 of the liquid storage compartment. An airflow passage extends past the heater assembly 120 and between the first portion 130 and the second portion 135 of the liquid storage compartment.

[0057] The system is configured to allow a user to puff or draw on the mouth-end opening 110 of the cartridge 100 to thereby draw aerosol into their mouth. In operation, as the user puffs on the mouth-end opening 110, air is drawn from the air inlet 150 through the airflow passages 140, 145, past the heater assembly 120 and into the mouth-end opening 110. When the system is activated, the control electronics 220 controls the supply of power from the battery 210 to the cartridge 100, which in turn controls the amount and characteristics of the vapor generated by the heater assembly 120. The control electronics 220 may include an airflow sensor, and may provide power to the heater assembly 120 when the airflow sensor detects a user puffing on the cartridge 100. This type of control device is well established in aerosol generating systems such as inhalers and e-cigarettes. Thus, when a user draws on mouth-end opening 110 of cartridge 100, heater assembly 120 is activated to generate a vapor that is entrained in the airflow passing through airflow passage 140. The vapor cools in the airflow in airflow passage 145 to form an aerosol that is then drawn through mouth-end opening 110 into the user's mouth.

[0058] In operation, the mouth end opening 110 is typically the highest point of the device. The construction of the cartridge 100, and in particular the arrangement of the heater assembly 120 between the first portion 130 and the second portion 135 of the liquid storage compartment, is advantageous because it utilizes gravity to ensure that liquid substrate is delivered to the heater assembly 120 even as the liquid storage compartment begins to empty, yet prevents oversupply of liquid to the heater assembly 120, which may lead to leakage of liquid into the airflow passage 140.

[0059] Although the embodiments described herein are of a two-part system comprising a cartridge and a reusable device containing power and control electronics, the same arrangement for the liquid reservoir and airflow can be implemented in a one-part system in which the power supply and control electronics are provided within a single housing with the heater assembly, liquid reservoir and mouthpiece, and therefore any reference to a cartridge in the following embodiments may apply equally to the one-part system as a whole.

[0060] Figure 2 is a first cross-section of a cartridge according to one embodiment of the invention, and Figure 3 is a second cross-section perpendicular to the cross-section of Figure 2.

[0061] The cartridge 100 of Figures 2 and 3 comprises an outer housing 105 having a mouth end with a mouth end opening 110 and a connection end opposite the mouth end. Within the housing 105 is a liquid storage compartment that holds a liquid aerosol-forming substrate 131. Liquid is contained within the liquid storage compartment by three components: an upper storage compartment housing 137, a heater mount 134, and an end cap 138. A heater assembly 120 is held within the heater mount 134. A wicking element 136 is provided within the second portion 135 of the liquid storage compartment and abuts the heating element in a central region of the heater assembly 120. The wicking element is oriented to transport the liquid to the heating element. The heating element 122 comprises a mesh heating element formed from a plurality of filaments. Details of this type of heating element structure are described, for example, in WO 2015 / 117702. An airflow passage 140 extends between the first portion 130 and the second portion 135 of the liquid storage compartment. The bottom wall of the airflow passage 140 contains the heating element 122 and heater mount 134, the side wall of the airflow passage 140 contains portions of the heater mount 134, and the top wall of the airflow passage 140 contains a portion of the upper storage compartment housing 137. The airflow passage 140 has a vertical portion 145 that extends through the liquid storage compartment first portion 130 toward the mouth end opening 110, as shown in FIG.

[0062] The heater assembly 120 is generally planar and has two sides. The first side of the heater assembly 120 faces the first portion 130 of the liquid storage compartment and the mouth end opening 110. The second side of the heater assembly 120 contacts the wicking element 136 and the liquid 131 in the liquid storage compartment and faces the connection end 115 of the cartridge 100. The heater assembly 120 is closer to the connection end so that electrical connection of the heater assembly 120 to a power source can be accomplished simply and robustly, as will be described. The first portion 130 of the liquid storage compartment is larger than the second portion 135 of the liquid storage compartment and occupies the space between the heater assembly 120 and the mouth end opening 110 of the cartridge 100. Liquid in the first portion 130 of the liquid storage compartment can travel to the second portion 135 of the liquid storage compartment through liquid channels 133 on either side of the heater assembly 120. Although two channels are provided in this embodiment to provide a symmetrical structure, only one channel is necessary. The channel is an enclosed liquid flow path defined between the upper storage compartment housing 137 and the heater mount 134 .

[0063] The wicking element 136 has a front surface that contacts the contact surface of the heating element and a rear surface opposite the front surface. The front surface of the wicking element 136 is pressed into contact with the contact surface of the heating element by the action of pressing the press elements 141, 142 against the rear surface of the heating element. The press elements 141, 142 in the embodiment shown in Figures 2 and 3 are rods positioned between the wicking element and the end cap 138 of the housing. The press elements include a central pin 141 that contacts the wicking element in a central region of the rear surface and a number of outer pins 142 that contact the periphery of the rear surface. The central pin may be made longer than the outer pins to provide a greater compressive force to the central region of the wicking element. The space 144 between the press elements allows the liquid aerosol-forming substrate to reach the wicking element. The central pin and the outer pins may themselves be hollow to allow the liquid to pass through. The press elements improve the uniformity of the contact between the wicking element and the heating element and therefore improve the uniformity of the liquid delivery to the heating element.

[0064] The cartridge 100 shown in Figures 2 and 3 may be assembled by first molding the heater mount 134 around the heater assembly 120. The heater assembly includes a mesh heating element 122 secured to a pair of tin contact pads, which have a much lower electrical resistivity than the heating element 122, as described. The contact pads 121 are secured to both ends of the heating element 122. The heater mount 134 is then secured to the upper reservoir housing using welding or adhesive. The wicking element 136 is inserted into the second portion 135 of the liquid storage compartment. The press element and end cap 138 are then secured to the heater mount to seal the liquid storage compartment. The press elements 141, 142 may be integrally formed with the end cap 138. Alternatively, the heater mount 134, wicking element 136, and end cap 138 can be first assembled before being secured to the upper reservoir housing.

[0065] Figure 4 illustrates several possible cross-sectional shapes of the press elements 141, 142. As shown, the press elements can have a solid or hollow cross-section. The examples shown in Figure 4 are of circular cross-sections 150, 151, triangular cross-sections 152, 153, rectangular cross-sections 154, 155, pentagonal cross-sections 156, 157, and cross-shaped cross-sections 158, 159.

[0066] Another embodiment of a press element is shown in Figure 5. A single press element of honeycomb structure 160 can be used, extending across part or all of the rear surface of the wicking element.

[0067] FIG. 6 is an exploded view of a cartridge of the type shown in FIG. 2, but with a different housing structure. The cartridge comprises an upper storage housing 170 forming a mouthpiece, and a rear housing 172 joined by a seal joint 174. A heater assembly is held within a heater mount 176, which is molded around the heater assembly to secure the heater assembly. The heater mount 176 is held within the rear housing 172. An opening is provided within the rear housing to allow electrical contact between the heater assembly and an external power source. A wicking element 178 is provided within the heater mount 176 for contacting the heater assembly, as described in connection with the embodiment of FIGS. 2 and 3. A removable seal tab 177 is provided to cover the heating element prior to use. A flavor identifier 179 is provided at the mouthpiece end of the upper storage housing to indicate the flavor of the liquid held within the cartridge.

[0068] Figure 7 is a cross-section of the wicking element of the cartridge of Figure 6. The wicking element 178 has a front surface 180 and a rear surface 182. The front surface 180 is dome-shaped. The rear surface 182 is planar. The wicking element is oriented so that the front surface contacts the heating element. As shown in Figure 7, the rear surface 182 has a central region 184 and a peripheral region 186.

[0069] FIG. 8 shows a cross section through a portion of the rear housing and heater mount of the cartridge of FIG. 7. FIG. 8 shows a wicking element 178 with its front surface in contact with a heating element 192 held within a heater mount 176. The front surface of the wicking element 178 is pressed into contact with the heating element 192 by a press element 190. The press element 190 rests on the rear housing 172. The press element 190 contacts the periphery of the rear surface of the wicking element to urge the wicking element against the heating element. This provides contact between the heating element and the wicking element to ensure continuous and consistent delivery of liquid to the heating element.

[0070] Figures 9a, 9b, and 9c show different views of the press element 190 of Figure 8. Figure 9a is a perspective view, Figure 9b is a plan view, and Figure 9c is a cross-sectional view. The press element includes an annular hub 194 from which four protrusions 196 extend. A central hole 198 is formed in the annular hub through which the liquid substrate can pass. The protrusions 196 contact the wicking element and press the wicking element into contact with the heating element. The height of the protrusions can be selected to provide the necessary pressing force. The press element of Figures 9a, 9b, and 9c is robust and capable of providing significant compressive force against the wicking element.

[0071] Figures 10a and 10b show an alternative design of the press element. The press element shown in Figures 10a and 10b is similar to the press element shown in Figure 9a. The press element includes an annular hub 204 from which four protrusions 206 extend. A central hole is formed in the annular hub through which the liquid substrate can pass. The protrusions 206 contact the wicking element and press the wicking element into contact with the heating element. However, the front surface 208 of the press element formed by the protrusions has a convex dome shape that matches the dome shape of the wicking element. The protrusions 206 also extend further inward such that the protrusions in the embodiment of Figure 9a provide a greater pressing force to the central region of the rear surface of the wicking element.

[0072] FIG. 11 shows a further alternative design of the press element. The press element shown in FIG. 11 is similar to the press element shown in FIGS. 10a and 10b. The press element includes an annular hub 214 from which four protrusions 216 extend. A central hole is formed in the annular hub through which the liquid substrate can pass. The protrusions 216 contact the wicking element and press it into contact with the heating element. The front surface 218 of the press element formed by the protrusions has a convex dome shape that matches the dome shape of the wicking element. In the embodiment of FIG. 11, the front surface 218 has a smaller diameter than the front surface 208 of the embodiment of FIGS. 10a and 10b. This removes the compression force on the periphery of the wicking element and provides compression only to the central region.

[0073] Figure 12 is a schematic cross-section of a cartridge with an alternative pressing element. Figure 12 shows a cross-section of a cartridge similar to Figure 2. The same reference numbers are used in Figure 12 as are used in Figure 2 for identical elements.

[0074] The cartridge 100 of FIG. 12 includes an outer housing 105 having a mouth end with a mouth end opening 110 and a connecting end opposite the mouth end. Within the housing 105 is a liquid storage compartment that holds a liquid aerosol-forming substrate 131. Liquid is contained within the liquid storage compartment by three components: an upper storage compartment housing 137, a heater mount 134, and an end cap 138. A heater assembly 120 is held within the heater mount 134. A wicking element 136 is provided within a second portion 135 of the liquid storage compartment and abuts a heating element in a central region of the heater assembly 120. The wicking element is oriented to transport liquid to the heating element. The heating element 122 includes a mesh heating element. An airflow passage 140 extends between the first portion 130 and the second portion 135 of the liquid storage compartment. A bottom wall of the airflow passage 140 contains the heating element 122 and the heater mount 134, a side wall of the airflow passage 140 contains portions of the heater mount 134, and a top wall of the airflow passage 140 contains a portion of the upper storage compartment housing 137. The airflow passage 140 has a vertical portion 145 that extends through the first portion 130 of the liquid storage compartment.

[0075] The heater assembly 120 is generally planar and has two sides. The first side of the heater assembly 120 faces the first portion 130 of the liquid storage compartment and the mouth end opening 110. The second side of the heater assembly 120 contacts the wicking element 136 and the liquid 131 in the liquid storage compartment and faces the connecting end 115 of the cartridge 100. The heater assembly 120 is closer to the connecting end so that electrical connection of the heater assembly 120 to a power source can be accomplished simply and robustly, as will be described. Liquid in the first portion 130 of the liquid storage compartment can travel to the second portion 135 of the liquid storage compartment through liquid channels 133 on either side of the heater assembly 120.

[0076] The wicking element 136 has a front surface that contacts the contact surface of the heating element and a rear surface opposite the front surface. The front surface of the wicking element 136 is pressed into contact with the contact surface of the heating element by the action of pressing the mesh press element 220 against the rear surface of the heating element. The mesh press element may be press-fit or may otherwise be mechanically secured to the heater mount 134. For example, the heater mount may include one or more internal ribs through which the mesh press element 220 may be extruded. When secured to the heater mount, the press element provides a compressive force across the rear surface of the wicking element. The mesh press element 220 may have a honeycomb structure, for example, as shown in FIG. 5.

[0077] FIG. 13 is a flow diagram of a method for assembling the above-mentioned aerosol generating system or cartridge. In a first step 300, a housing is provided to enclose a reservoir of liquid aerosol-forming substrate, a heating element, and a compressible wicking element. The heating element may be provided in a heater mount as described above. The heater mount may hold the wicking element. In a second step 310, the wicking element is pressed against the contact surface of the heating element using a press element such that the wicking element is positioned between the press element and the heating element. This can be done when the heater mount is fixed to the housing and the press element is integral with the housing or sandwiched between the housing and the wicking element. In a third step 320, the housing is filled with the liquid aerosol-forming substrate. The liquid aerosol-forming substrate is drawn into the wicking element so that it comes into contact with the heating element. In a fourth step 330, the housing is sealed to prevent leakage of the liquid aerosol-forming substrate prior to use.

Claims

1. 1. A cartridge for an aerosol generation system, the cartridge comprising: a housing enclosing a reservoir of liquid aerosol-forming substrate; a heating element having a contact surface; a compressible wicking element positioned in contact with the contact surface of the heating element and in communication with the liquid aerosol-forming substrate within the reservoir; a press element, the wicking element being positioned between the press element and the heating element, the press element pressing the wicking element to urge the wicking element into contact with the contact surface of the heating element.

2. 2. The cartridge of claim 1, wherein the wicking element has a front surface in contact with the contact surface of the heating element and a rear surface in contact with the press element, the press element contacting the rear surface in a central region spaced inwardly from a periphery of the rear surface.

3. The cartridge of claim 2 , wherein the pressing element is provided such that the wicking element is compressed to a greater extent in the central region than at the periphery of the rear face.

4. A cartridge according to any one of claims 2 to 4, wherein the wicking element has a greater thickness in the central region than at the periphery.

5. A cartridge according to any one of claims 2 to 4, wherein in an uncompressed state, the wicking element has a greater porosity in the central region than in the periphery.

6. A cartridge according to any one of claims 1 to 5, wherein the pressing element is liquid permeable.

7. A cartridge according to any one of claims 1 to 6, wherein the pressing element comprises a hollow pressing member through which liquid aerosol-forming substrate from the reservoir can pass to reach the wicking material.

8. A cartridge according to any preceding claim, wherein the heating element is fluid permeable.

9. The cartridge according to any one of claims 1 to 8, wherein the heating element is planar.

10. The cartridge of any one of claims 1 to 9, wherein the heating element comprises a mesh.

11. A cartridge according to any preceding claim, wherein the heating element includes electrical contacts for connection to an external power source.

12. A cartridge according to any preceding claim, wherein the heating element comprises a susceptor configured to inductively heat the liquid aerosol-forming substrate to vaporize it.

13. A cartridge according to any preceding claim, wherein the pressing element comprises a dome-shaped surface in contact with a rear surface of the wicking element.

14. A cartridge according to any one of claims 1 to 13, wherein the liquid aerosol-forming substrate from the reservoir can pass through the pressing element in a direction in which the pressing element presses against the wicking element.

15. An aerosol generating system comprising a cartridge according to any one of claims 1 to 14.

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