Heater assembly

Abstract

A heater assembly (300) for use in an aerosol-generating system (100) is provided. The heater assembly (300) comprises a liquid aerosol-forming substrate comprising at least two compounds, wherein a first compound has a first boiling point and a second compound has a second boiling point. The heater assembly (300) comprises a retention material (302) comprising the aerosol-forming substrate. The heater assembly further comprises a heating element (304) configured to heat the retention material by passing an electric current along a length of the heating element, wherein the heating element (304) is formed from a strip of material, wherein a cross-sectional area of the strip of material gradually decreases along the length of the strip of material to provide a temperature gradient along a surface of the retention material (302).

Description

[0001] This disclosure relates to a heater assembly. More particularly, this disclosure relates to a heater assembly for use in an aerosol generation system. This disclosure also relates to a cylinder including a heater assembly, an aerosol generation system including a heater assembly, and a method for heating a liquid aerosol forming matrix within the heater assembly.

[0002] In many known aerosol generation systems, a liquid aerosol-forming matrix is ​​heated and evaporated to form vapor. The vapor is then cooled and condensed to form an aerosol. In some aerosol generation systems, such as electrically heated smoking systems, this aerosol is then inhaled by the user.

[0003] Typically, a liquid aerosol forming matrix comprises several compounds that evaporate when heated. These compounds can have different boiling points. For example, a liquid aerosol forming matrix may include nicotine (which has a boiling point of about 247 degrees Celsius at atmospheric pressure) and glycerol (which has a boiling point of about 290 degrees Celsius at atmospheric pressure).

[0004] When a liquid aerosol forming matrix comprising compounds with different boiling points is heated, the compounds with lower boiling points can evaporate before the compounds with higher boiling points. Alternatively or additionally, the compounds with lower boiling points can evaporate at a higher rate compared to the compounds with higher boiling points.

[0005] This may be undesirable because the interactions and combinations between different compounds can be limited. For example, a liquid aerosol forming matrix may include nicotine compounds and organic acid compounds with different boiling points. Both compounds can evaporate. Nicotine in the liquid aerosol forming matrix can form free nicotine base upon evaporation. However, it may be desirable to generate aerosols containing nicotine salts rather than free nicotine bases. To form such nicotine salts, free nicotine bases can be protonated by evaporating organic acids. However, this protonation can be limited if the organic acids evaporate only after the nicotine has evaporated, or evaporate more slowly than required to protonate a suitable proportion of free nicotine bases.

[0006] Furthermore, the fact that some compounds in the aerosol-forming matrix evaporate at a higher rate than others may undesirably cause the properties of the generated aerosol to change over time, for example, during the pumping process of the aerosol-generating system. This may be because, near the start of pumping, when the heating element is activated and the temperature rises, the liquid aerosol-forming matrix near the heating element can reach a first temperature at which first compounds with lower boiling points evaporate, but second compounds with higher boiling points do not evaporate. Then, in the later stages of pumping, the liquid aerosol-forming matrix near the heating element can reach a second temperature at which second compounds with higher boiling points evaporate. However, by this time, many of the first compounds in the liquid aerosol-forming matrix near the heating element may have already evaporated. Therefore, near the start of pumping, the generated aerosol may include a larger proportion of the first compounds, and in the later stages of pumping, the generated aerosol may include a larger proportion of the second compounds.

[0007] Alternatively or additionally, the properties of the generated aerosol can change during several pumping operations. This can occur if the compounds in the liquid aerosol forming matrix do not evaporate at an appropriate rate. For example, the liquid aerosol forming matrix may comprise X% by mass of a first compound and Y% by mass of a second compound. If the liquid aerosol forming matrix does not evaporate to produce vapor comprising the first compound and the second compound in a mass ratio of X:Y, the composition of the liquid aerosol forming matrix can change during vapor generation. This can subsequently cause changes in the properties of the aerosol generated from the liquid aerosol forming matrix.

[0008] The purpose of this invention is to control the evaporation of various compounds that form a liquid aerosol matrix, wherein these compounds have different boiling points.

[0009] According to one aspect of this disclosure, a heater assembly for an aerosol generation system is provided, the heater assembly comprising a liquid aerosol forming matrix. The liquid aerosol forming matrix may comprise at least two compounds, wherein a first compound has a first boiling point and a second compound has a second boiling point. The heater assembly may include a holding material comprising the liquid aerosol forming matrix. The heater assembly may include a heating element configured to heat the holding material by passing an electric current along the length of the heating element. The heating element may be formed of a material strip, wherein the cross-sectional area of ​​the material strip gradually decreases along the length of the material strip to provide a temperature gradient along the surface of the holding material.

[0010] The cross-sectional area of ​​the material strip can gradually decrease along the length of the material strip, from the maximum cross-sectional area at the first end of the material strip to the minimum cross-sectional area at the second end of the material strip.

[0011] The heater assembly can provide areas along the surface of the retaining material that increase in temperature at a higher rate and areas that increase in temperature at a lower rate.

[0012] Advantageously, the heater assembly can improve the control of evaporation of different compounds in the liquid aerosol forming matrix. The heater assembly allows liquid aerosol forming matrix compounds with higher and lower boiling points to evaporate simultaneously at a desired rate. The heater assembly allows liquid aerosol forming matrix compounds with higher and lower boiling points to evaporate in a more preferred ratio. The heater assembly can provide the generation of aerosols with a more desired composition. The heater assembly can provide more consistent generation of aerosols with desired properties.

[0013] The material strip may have a cross-sectional area that gradually decreases along its length. The width of the material strip may gradually decrease along its length. Alternatively or additionally, the thickness of the material strip may gradually decrease along its length.

[0014] The material strip can be folded on itself to provide at least one overlapping portion, which has a greater thickness and lower resistance compared to the adjacent non-overlapping portion of the material strip.

[0015] The at least one overlapping portion provides a portion of the heating element with a lower temperature compared to the adjacent non-overlapping portions of the material strip. The material strip can be folded any number of times along its length. For example, the material strip can be folded to provide one, two, three, four, five, six, seven, eight, nine, or ten overlapping portions along its length.

[0016] Advantageously, the folded strip of material and the resulting overlap can create more regions of higher temperature and more regions of lower temperature along the surface of the retaining material. Alternatively or additionally, this can provide more regions along the surface of the retaining material that increase in temperature at a greater rate and more regions that increase in temperature at a lesser rate. This allows liquid aerosols with higher and lower boiling points to form matrix compounds that evaporate simultaneously at a preferred rate. Advantageously, the production of heating elements formed from folded strips of material may require a simple manufacturing process.

[0017] The heating element may include more than one material. The heating element may include a first heating element material and a second heating element material. The second heating element material may be different from the first heating element material. The first heating element material may be located at a first position along the length of the material strip. The second heating element material may be located at a second position along the length of the material strip. The first heating element material may have a first resistivity, and the second heating element material may have a second resistivity different from the first resistivity.

[0018] Advantageously, heating elements comprising more than one material can provide an increased temperature gradient along the surface of the holding material. This increased temperature gradient can provide more regions along the surface of the holding material that increase in temperature at a higher rate and more regions that increase in temperature at a lower rate. The increased temperature gradient can further influence the evaporation rate of different compounds within the liquid aerosol formation matrix. As described above, this can lead to the formation of aerosols with a more desired composition. Alternatively or additionally, heating elements comprising more than one material provide more consistent formation of aerosols with desired properties.

[0019] Heating elements or portions thereof may comprise or be formed of any material having suitable electrical and mechanical properties (e.g., suitable resistive materials). Suitable materials include, but are not limited to: semiconductors (e.g., doped ceramics), “conductive” ceramics (e.g., molybdenum disilicide), carbon, graphite, metals, metal alloys, and composite materials made of ceramic and metallic materials. Such composite materials may comprise 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 metal alloys include stainless steel; constantan; nickel-containing alloys, cobalt-containing alloys, chromium-containing alloys, aluminum-containing alloys, titanium-containing alloys, zirconium-containing alloys, hafnium-containing alloys, niobium-containing alloys, molybdenum-containing alloys, tantalum-containing alloys, tungsten-containing alloys, tin-containing alloys, gallium-containing alloys, manganese-containing alloys, and iron-containing alloys; and nickel-, iron-, and cobalt-based superalloys; stainless steel; Iron-aluminum based alloys and iron-manganese-aluminum based alloys. "Is a registered trademark of Titanium Metals Corporation, 1999 Broadway Suite 4300, Denver, Colorado." In composite materials, the resistive material may optionally be embedded in, encapsulated in, or coated with an insulating material, or vice versa, depending on the energy transfer kinetics and desired external physicochemical properties. The heating element or portions thereof may comprise a metal-etched foil insulated between two layers of inert material. In this case, the inert material may include... Polyimide or mica foil. It is a registered trademark of EIdu Pont de Nemours and Company, 1007 Market Street, Wilmington, Delaware 19898, United States of America.

[0020] The heater assembly may include multiple heating elements. Preferably, at least one heating element provides a temperature gradient along the surface of the retaining material. Preferably, the cross-section of the retaining material is closed or partially closed within a volume defined between two heating elements. The features described with respect to the first heating element may be applied to any of the multiple heating elements.

[0021] A closed or partially closed volume defined between two heating elements can provide a temperature gradient along the surface of the retaining material.

[0022] The positioning of the plurality of heating elements can be used to increase the temperature gradient along the surface of the holding material. Advantageously, identical material strips can be manufactured for various heater assemblies comprising multiple heating elements, wherein different temperatures or temperature gradients can be achieved by rearranging the heating elements. For example, a first heater assembly comprising two identical material strips can have a larger temperature gradient than a second heater assembly comprising two other identical material strips. The first heater assembly can have material strips positioned such that portions of the material strip having a substantially minimum cross-sectional area are arranged closer together than portions of the material strip having a substantially maximum cross-sectional area. If the second heater assembly comprises identical material strips spaced at a uniform distance, this can produce a larger temperature gradient along the surface of the holding material compared to the second heater assembly. Thus, the first heater assembly can simultaneously evaporate liquid aerosols forming matrix compounds with higher and lower boiling points in more different proportions.

[0023] The heating element may be in contact with the retaining material. The heating element may be on the surface of the retaining material. The heating element may be embedded or partially embedded in the retaining material.

[0024] As described above, the positioning of the heating element or multiple heating elements can be used to increase the temperature gradient along the surface of the retaining material. This allows liquid aerosols with higher and lower boiling points to form matrix compounds that evaporate simultaneously at a desired rate.

[0025] The heating element can be configured for resistance heating. The material strip can be perforated or can be a mesh.

[0026] Advantageously, heating elements comprising mesh or perforated material strips can provide a large surface area. This large surface area allows for efficient evaporation of the liquid aerosol forming matrix.

[0027] The heater assembly may include a reservoir for storing an aerosol-forming matrix. The heater assembly may include a reservoir for a liquid aerosol-forming matrix. Unless otherwise expressly stated, the term "reservoir" may refer to a reservoir for storing a liquid aerosol-forming matrix or a reservoir for a liquid aerosol-forming matrix. The reservoir may be configured to store, or be capable of storing, at least 0.2, 0.5, or 1 ml of liquid aerosol-forming matrix. The reservoir may be configured to store, or be capable of storing, less than 2, 1.8, or 1.5 ml of liquid aerosol-forming matrix.

[0028] The retaining material can be a porous material. The retaining material can be a ceramic material. Preferably, the retaining material is a capillary retaining material. The liquid aerosol forming matrix storage component can store or be configured to store the liquid aerosol forming matrix.

[0029] The retaining material is kept in fluid communication with the reservoir. In this case, during use, the sections of the heating element farther from the reservoir of the liquid aerosol forming matrix, or the areas in the retaining material surrounding these sections of the heating element, can reach higher temperatures than the sections or areas closer to the reservoir of the liquid aerosol forming matrix. This is because for the sections of the heating element closer to the reservoir of the liquid aerosol forming matrix, more heat can be transferred from the heating element to the reservoir of the liquid aerosol forming matrix, or heat can be transferred from the heating element to the reservoir of the liquid aerosol forming matrix at a higher rate.

[0030] The retaining material may include a liquid aerosol forming matrix, or may be a material impregnated with a liquid aerosol forming matrix, or may be a material configured to be impregnated with a liquid aerosol forming matrix. The retaining material may have a fibrous or sponge-like structure. The retaining material may include a capillary material. The retaining material may include a capillary bundle. For example, the retaining material may include one or more of fibers, wires, and fine-pore tubes.

[0031] The retaining material may include a sponge-like or foam-like material. The structure of the retaining material may form multiple small holes or tubes through which liquid can be transported via capillary action.

[0032] The retaining material may include any suitable material or combination of materials. Suitable materials include, but are not limited to: sponge or foam materials, ceramic-based or graphite-based materials in the form of fibers or sintered powders, foamed metals or plastic materials, such as fibrous materials made from spun or extruded fibers, such as cellulose acetate, polyester or bonded polyolefins, polyethylene, polyester or polypropylene fibers, nylon fibers, or ceramics. The retaining material may have any suitable capillary action and porosity to be used with different liquid aerosol forming matrices with different physical properties.

[0033] The aerosol forming matrix is ​​preferably absorbed in a retaining material. The retaining material may be configured to store or be able to store at least 0.02, 0.05, 0.1, 0.2 or 0.5 ml of liquid aerosol forming matrix.

[0034] The heating element or multiple heating elements may be configured to be heated, and may be heated to at least 50, 100, 150, 200, 250, 300, 350 or 400 degrees Celsius during use. In use, a fifth portion of the heating element may be heated to at least 50, 100, 150, 200, 250, 300, 350 or 400 degrees Celsius.

[0035] The minimum cross-sectional area of ​​the heating element along the length of the material strip can be at least 50% of the maximum cross-sectional area of ​​the heating element along the length of the material strip.

[0036] Advantageously, this can provide a predictable temperature difference along the length of the material band. Therefore, it can provide a predictable temperature gradient along the surface that holds the material.

[0037] The boiling point of the first compound can be between 240°C and 250°C. The boiling point of the second compound can be 247°C. The boiling point of the third compound can be between 285°C and 295°C. The boiling point of the fourth compound can be 290°C. The first compound can be nicotine, and the second compound can be glycerol. The temperature gradient along the surface of the material can be between 247°C and 290°C. This can produce an evaporating compound of nicotine and glycerol in a preferred ratio.

[0038] According to another aspect of this disclosure, a cylinder for an aerosol generation system is provided, the cylinder including the heater assembly of this disclosure.

[0039] The cylinder preferably includes an air inlet and an air outlet, wherein the airflow path can be defined between the air inlet and the air outlet. A heating element can be located downstream of the air inlet. A heating element can be located upstream of the air outlet. Air drawn from the air inlet to the air outlet can flow through, pass through, or pass through the heating element.

[0040] Advantageously, providing an airflow across, through, or through the heater assembly or heating element allows steam formed by the heater assembly to be entrained in the airflow.

[0041] The air inlet can be positioned as the part closest to the heating element with substantially the lowest resistance. The air outlet can be positioned as the part closest to the heating element with substantially the highest resistance.

[0042] In use, the air entering the air inlet can be at atmospheric temperature. Advantageously, positioning the air inlet to the portion closest to the heating element with substantially the lowest resistance and the air outlet to the portion closest to the heating element with substantially the highest resistance can increase the temperature gradient along the surface of the retaining material. Advantageously, as previously stated, this can produce a consistent aerosol with the desired composition. Alternatively or additionally, this positioning of the air inlet and air outlet can provide predictable temperature variations of the air within the aerosol generation system, and thus the heater assembly can maintain the desired non-uniform temperature.

[0043] The air in the airflow path preferably passes through the surface of the retaining material. Preferably, the heater assembly provides a temperature gradient along the surface of the retaining material.

[0044] During use, this increases the temperature of the airflow at the air outlet. Some users may prefer this, as it more accurately simulates the experience of smoking a regular cigarette or cigar.

[0045] The cylinder can be configured to engage with and disengage from the aerosol generating device. The aerosol generating device may include a power source. The power source can be configured to supply power to a heating element. The power source can be configured to supply power to the heating element only when the cylinder is engaged with the aerosol generating device.

[0046] The cartridge may include a mouthpiece. The mouthpiece may include an air outlet. In use, when the cartridge is engaged with an aerosol generating device, a user can inhale through the mouthpiece of the cartridge. This may cause air to flow in through the air inlet, then across, over, through, or through the heater assembly or heating element, and then through the air outlet.

[0047] The cylinder may include a first electrical contact and a second electrical contact electrically connected to the heating element. The electrical contacts may include one or more of the following: tin, silver, gold, copper, aluminum, steel (e.g., stainless steel), phosphor bronze, tin alloyed with antimony, tin alloyed with zirconium, tin alloyed with bismuth, or tin alloyed with other components that improve resistance to organic acids.

[0048] The electrical contacts can be configured to form an electrical connection with the corresponding electrical contacts on the aerosol generating device when the cylinder is engaged with the aerosol generating device.

[0049] The heating element can be located in the airflow path between the air inlet and the air outlet of the cylinder.

[0050] According to another aspect of this disclosure, an aerosol generation system is provided. The aerosol generation system may include the heater assembly of this disclosure.

[0051] The aerosol generation system preferably includes an air inlet and an air outlet, wherein an airflow path can be defined between the air inlet and the air outlet. Air drawn from the air inlet to the air outlet preferably flows through, passes over, or passes through a heating element. The air inlet can be positioned as the portion closest to the heating element with substantially the lowest resistance. The air outlet can be positioned as the portion closest to the heating element with substantially the highest resistance. The air in the airflow path preferably crosses the surface of the retaining material, and the airflow path forms matrix fluid contact with the aerosol. Preferably, the heater assembly provides a temperature gradient across the surface of the retaining material.

[0052] Advantageously, the aerosol generation system can improve the control of the evaporation of different compounds in the liquid aerosol forming matrix. The aerosol generation system allows liquid aerosol forming matrix compounds with higher and lower boiling points to evaporate simultaneously at a desired rate. The aerosol generation system allows liquid aerosol forming matrix compounds with higher and lower boiling points to evaporate in a more preferred ratio. The aerosol generation system can provide the generation of aerosols with a more desired composition. The aerosol generation system can provide more consistent generation of aerosols with desired properties.

[0053] The aerosol generation system may include a mouthpiece at the air outlet. The aerosol generation system may be an electronic cigarette system.

[0054] The aerosol generation system may include a cylinder according to the present disclosure.

[0055] The system may include an aerosol generating device. The system may include a cylinder, the cylinder including a heater assembly.

[0056] The cylinder can be configured to engage with the aerosol generating device. The cylinder can also be configured to detach from the aerosol generating device.

[0057] An aerosol generation system (e.g., an aerosol generation device of an aerosol generation system) may include a power supply device, such as a battery. The power supply device may be configured to supply power to a heating element. This can be used to heat the heating element. The power supply device may be configured to supply power to the heating element only when the cylinder is engaged with the aerosol generation device.

[0058] The aerosol generating apparatus may include a controller. The controller may be configured to control the power supply from the power supply device. Therefore, the controller can control the heating of the heating element.

[0059] The power supply device can be configured to supply power to the heating element for resistance heating. The power supply device can also be configured to supply power to the heating element for induction heating.

[0060] The aerosol generating device can be configured to engage with and disengage from the cylinder via a snap-fit ​​connection, corresponding thread, or any other suitable means. The aerosol generating device can be configured as at least a portion of the receiving cylinder. For example, the aerosol generating device may include a chamber configured as at least a portion of the receiving cylinder.

[0061] The aerosol generating device may include an air inlet. The aerosol generating device may include an air outlet. When the aerosol generating device is connected to the cylinder, the air outlet of the aerosol generating device may be in fluid communication with the air inlet of the cylinder.

[0062] The power supply device can be electrically connected to the first and second electrical contacts of the device. These first and second electrical contacts can be configured to form an electrical connection with corresponding first and second electrical contacts on the cylinder when the cylinder is engaged with the device. These corresponding first and second electrical contacts on the cylinder can be electrically connected to the heating element. Therefore, the power supply device can be configured to supply power to the heating element by allowing current to pass through it.

[0063] According to another aspect of this disclosure, a method is provided for heating a liquid aerosol forming matrix within a heater assembly for an aerosol generation system. The heater assembly may include a liquid aerosol forming matrix comprising at least two compounds, wherein a first compound may have a first boiling point and a second compound may have a second boiling point. The heater assembly may have a holding material comprising the aerosol forming matrix. A heating element may be configured to heat the holding material. The heating element may be formed from a strip of material, wherein the cross-sectional area of ​​the strip may gradually decrease along its length. The method may include passing an electric current along the length of the strip such that the heating element can provide a temperature gradient along the surface of the holding material.

[0064] Advantageously, this method can improve the control of evaporation of different compounds in the liquid aerosol forming matrix. The method for heating the liquid aerosol forming matrix allows liquid aerosol forming matrix compounds with higher and lower boiling points to evaporate simultaneously at a desired rate. The method for heating the liquid aerosol forming matrix allows liquid aerosol forming matrix compounds with higher and lower boiling points to evaporate in a more preferred ratio. The heater assembly can provide the generation of aerosols with a more desired composition. The heater assembly can provide more consistent generation of aerosols with desired properties.

[0065] The material strip may be folded to provide at least one overlapping portion, which has a greater thickness and lower resistance compared to adjacent non-overlapping portions of the material strip. The material strip may have a cross-sectional area that gradually decreases along its length. The width of the material strip may gradually decrease. Alternatively or additionally, the thickness of the material strip may gradually decrease.

[0066] As described above, the at least one overlapping portion can provide a portion of the material strip with a lower temperature compared to the adjacent non-overlapping portion of the material strip. Advantageously, the material strip folded in itself and the resulting at least one overlapping portion can create more regions of higher temperature and more regions of lower temperature along the surface of the holding material. Alternatively or additionally, this can provide more regions along the surface of the holding material that increase in temperature at a greater rate and more regions that increase in temperature at a lesser rate. This allows liquid aerosols with higher and lower boiling points to form matrix compounds to evaporate simultaneously at a preferred rate. Advantageously, the production of heating elements formed from material strips folded in themselves can allow for a simple manufacturing process.

[0067] According to another aspect of this disclosure, a heater assembly for an aerosol generation system is provided. The heater assembly may include: a liquid aerosol forming matrix comprising at least two compounds, wherein a first compound has a first boiling point and a second compound has a second boiling point; a holding material comprising the aerosol forming matrix; and a heating element configured to heat the holding material, wherein the heating element is formed of a material strip, wherein the material strip is folded in itself to provide at least one overlapping portion, the at least one overlapping portion having a greater thickness and lower resistance than an adjacent non-overlapping portion of the material strip to provide a temperature gradient along the surface of the holding material.

[0068] As used herein, the term "aerosol" refers to a dispersion of solid particles or droplets, or a combination of solid particles and droplets, in a gas. Aerosols can be visible or invisible. Aerosols can include vapors of substances that are typically liquid or solid at room temperature, as well as solid particles or droplets, or a combination of solid particles and droplets.

[0069] As used herein, the term "aerosol-forming matrix" refers to a matrix capable of releasing volatile compounds that can form aerosols. These volatile compounds can be released by heating or burning the aerosol-forming matrix.

[0070] The aerosol forming matrix can include a variety of compounds. These compounds can have different boiling points. For example, the aerosol forming matrix can include: a first compound having a first boiling point at atmospheric pressure; and a second compound having a second boiling point at atmospheric pressure, wherein the first boiling point is greater than the second boiling point.

[0071] Aerosol forming matrices may include aerosol forming agents. As used herein, the term "aerosol forming agent" refers to any suitable compound or mixture of compounds that promotes the formation of aerosols during use, such as stable aerosols that are substantially resistant to thermal degradation at the system's operating temperature. Suitable aerosol forming agents are well known in the art and include, but are not limited to: polyols, such as triethylene glycol, 1,3-butanediol, and glycerol; esters of polyols, such as mono-, di-, or triacetic acid esters of glycerol; and aliphatic esters of mono-, di-, or polycarboxylic acids, such as dimethyl dodecanoate and dimethyl tetradecanoate.

[0072] The aerosol-forming matrix may include nicotine. The aerosol-forming matrix may include water. The aerosol-forming matrix may include glycerol, also known as glycerol, which has a higher boiling point than nicotine. The aerosol-forming matrix may include plant-based materials. The aerosol-forming matrix may include homogenized plant-based materials. The aerosol-forming matrix may include tobacco. The aerosol-forming matrix may include tobacco-containing materials. Tobacco-containing materials may contain volatile tobacco flavor compounds. These compounds can be released from the aerosol-forming matrix upon heating. The aerosol-forming matrix may include homogenized tobacco materials. The aerosol-forming matrix may include other additives and ingredients, such as flavorings.

[0073] As used herein, the term "liquid aerosol forming matrix" refers to an aerosol forming matrix in a concentrated form. Therefore, a "liquid aerosol forming matrix" can be or may include one or more of liquids, gels, or slurries. If the liquid aerosol forming matrix is ​​or includes a gel or slurry, the gel or slurry may liquefy upon heating. For example, the gel or slurry may liquefy upon heating to temperatures below 50, 75, 100, 150, or 200 degrees Celsius.

[0074] As used herein, the term "heating element" refers to an element of a heater configured to be heated. For example, the term "heating element" can refer to an element configured to heat to at least 50, 100, 150, 200, 250, or 300 degrees Celsius. A heating element, or portions thereof, can be configured for resistance heating.

[0075] As used in this article, "embedded" can be used to mean enclosing, enclosing, closing, surrounding, or surrounding.

[0076] As used herein, the term "length" refers to the principal dimension in the longitudinal direction of an aerosol generation system or a component of an aerosol generation system (e.g., a strip of material used to form a heating element).

[0077] The boiling point of a liquid is the temperature at which the vapor pressure of the liquid equals the external pressure surrounding the liquid. As used herein, the term "boiling point" refers to the normal boiling point or atmospheric boiling point, which is the temperature at which the vapor pressure of the liquid equals the pressure at sea level (1 atmosphere).

[0078] As used herein, the term "transverse" refers to a direction perpendicular to the longitudinal axis at a given location along its length. Unless otherwise stated, any reference to the "cross section" of an aerosol generating system or a component of an aerosol generating system, such as a heater assembly or a heating element, refers to the transverse cross section.

[0079] The invention is defined in the claims. However, a non-exhaustive list of non-limiting examples is provided below. Any one or more features of these examples may be combined with any one or more features of another example, embodiment, or aspect described herein.

[0080] Example Ex1: A heater assembly for an aerosol generation system, the heater assembly comprising: a liquid aerosol forming matrix comprising at least two compounds, wherein a first compound has a first boiling point and a second compound has a second boiling point; a holding material comprising the liquid aerosol forming matrix; and a heating element configured to heat the holding material by passing an electric current through the length of the heating element, wherein the heating element is formed of a material strip, wherein the cross-sectional area of ​​the material strip gradually decreases along the length of the material strip to provide a temperature gradient along the surface of the holding material.

[0081] Example Ex2: The heater assembly according to Example Ex1, wherein the material strip is folded on itself to provide at least one overlapping portion, the at least one overlapping portion having a greater thickness and lower resistance compared to the adjacent non-overlapping portion of the material strip.

[0082] Example Ex3: The heater assembly according to Example Ex1 or Ex2, wherein the heating element includes a first heating element material and a second heating element material, wherein the first heating element material is in a first position along the length of the material strip, and the second heating element material is in a second position along the length of the material strip.

[0083] Example Ex4: The heater assembly according to Example Ex3, wherein the first heating element material has a first resistivity and the second heating element material has a second resistivity different from the first resistivity.

[0084] Example Ex5: A heater assembly according to any one of Examples Ex1 to Ex4 includes a plurality of heating elements.

[0085] Example Ex6: The heater assembly according to Example Ex5, wherein at least one heating element provides a temperature gradient along the surface of the holding material.

[0086] Example Ex7: A heater assembly according to any one of Examples Ex5 or Ex6, wherein the cross section of the retaining material is closed or partially closed in a volume defined between two heating elements.

[0087] Example Ex8: A heater assembly according to any one of Examples Ex1 to Ex7, wherein the heating element is in contact with the retaining material.

[0088] Example Ex9: A heater assembly according to any one of Examples Ex1 to Ex8, wherein the heating element is configured for resistance heating.

[0089] Example Ex10: A heater assembly according to any one of Examples Ex1 to Ex9, wherein the material strip is perforated.

[0090] Example Ex11: A heater assembly according to any one of Examples Ex1 to Ex9, wherein the material strip is a mesh.

[0091] Example Ex12: A heater assembly according to any one of Examples Ex1 to Ex11, wherein the retaining material is a porous material.

[0092] Example Ex13: A heater assembly according to any one of Examples Ex1 to Ex12, wherein the retaining material is a ceramic material.

[0093] Example Ex14: A heater assembly according to any one of Examples Ex1 to Ex13, wherein the retaining material is a capillary retaining material.

[0094] Example Ex15: A heater assembly according to any one of Examples Ex1 to Ex14, wherein the aerosol forming matrix is ​​absorbed in the retaining material.

[0095] Example Ex16: A heater assembly according to any one of Examples Ex1 to Ex15, wherein the minimum cross-sectional area along the length of the material strip is at least 10% smaller than the maximum cross-sectional area along the length of the material strip.

[0096] Example Ex17: A heater assembly according to any one of Examples Ex1 to Ex16, wherein the boiling point of the first compound is between 240 degrees Celsius and 250 degrees Celsius.

[0097] Example Ex18: A heater assembly according to any one of Examples Ex1 to Ex17, wherein the boiling point of the second compound is between 285 degrees Celsius and 295 degrees Celsius.

[0098] Example Ex19: A cylinder for an aerosol generation system, the cylinder comprising a heater assembly according to any one of Examples Ex1 to Ex18.

[0099] Example Ex20: The cylinder according to Example Ex19 includes an air inlet and an air outlet, wherein an airflow path is defined between the air inlet and the air outlet.

[0100] Example Ex21: The cylinder according to Example Ex20, wherein air drawn from the air inlet to the air outlet flows through, passes through or passes through the heating element.

[0101] Example Ex22: The cylinder according to Example Ex21, wherein the air inlet is positioned as the portion closest to the heating element with substantially the lowest resistance.

[0102] Example Ex23: The cylinder according to Examples Ex20 to Ex22, wherein the air outlet is positioned as the part closest to the heating element with substantially the highest resistance.

[0103] Example Ex24: A cylinder according to any one of Examples Ex20 to Ex23, wherein air in the airflow path passes through the surface of the retaining material.

[0104] Example Ex25: A cylinder according to any one of Examples Ex20 to Ex24, wherein the heater assembly provides a temperature gradient across the surface of the retaining material.

[0105] Example Ex26: An aerosol generation system comprising a heater assembly according to any of the foregoing examples.

[0106] Example Ex27: The aerosol generation system according to Example Ex26 includes an air inlet and an air outlet, wherein an airflow path is defined between the air inlet and the air outlet.

[0107] Example Ex28: The aerosol generation system according to Example Ex27, wherein air drawn from the air inlet to the air outlet flows through, passes through or passes through a heating element.

[0108] Example Ex29: An aerosol generating system according to any one of Examples Ex27 or Ex28, wherein the air inlet is positioned as the portion closest to the heating element having substantially the lowest resistance.

[0109] Example Ex30: An aerosol generation system according to any one of Examples Ex27 or Ex28, wherein the gas flow path outlet is positioned as the portion closest to the heating element with substantially the highest resistance.

[0110] Example Ex31: An aerosol generation system according to any one of Examples Ex26 to Ex30, wherein air in the airflow path passes through the surface of the retaining material, and the airflow path is in contact with the aerosol forming matrix fluid.

[0111] Example Ex32: An aerosol generation system according to any one of Examples Ex26 to Ex31, wherein the heater assembly provides a temperature gradient across the surface of the retaining material.

[0112] Example Ex33: An aerosol generating system according to any one of Examples Ex27 to Ex32, including a mouthpiece at the air outlet.

[0113] Example Ex34: An aerosol generating system according to any one of Examples Ex26 to Ex33, wherein the aerosol generating system is an electronic cigarette system.

[0114] Example Ex35: A method for heating an aerosol forming matrix within a heater assembly for an aerosol generation system, the heater assembly comprising: a liquid aerosol forming matrix comprising at least two compounds, wherein a first compound has a first boiling point and a second compound has a second boiling point; a holding material containing the liquid aerosol forming matrix; and a heating element configured to heat the holding material, wherein the heating element is formed of a material strip, wherein the cross-sectional area of ​​the material strip gradually decreases along the length of the material strip; the method comprising passing an electric current along the length of the material strip such that the heating element provides a temperature gradient along the surface of the holding material.

[0115] Example Ex36: According to the method of Example Ex35, the material strip is folded on itself to provide at least one overlapping portion, the at least one overlapping portion having a greater thickness and lower resistance compared to the adjacent non-overlapping portion of the material strip.

[0116] Example Ex37: A heater assembly for an aerosol generation system, the heater assembly comprising: a liquid aerosol forming matrix comprising at least two compounds, wherein a first compound has a first boiling point and a second compound has a second boiling point; a holding material comprising the aerosol forming matrix; and a heating element configured to heat the holding material, wherein the heating element is formed of a material strip, wherein the material strip is folded on itself to provide at least one overlapping portion, the at least one overlapping portion having a greater thickness and lower resistance than an adjacent non-overlapping portion of the material strip, to provide a temperature gradient along the surface of the holding material.

[0117] Several examples will now be described further with reference to the accompanying drawings, in which:

[0118] Figure 1 A longitudinal cross-sectional view of a first aerosol generation system including a cylinder comprising a first heater assembly is shown.

[0119] Figure 2 A cross-sectional view of the first heater assembly is shown;

[0120] Figure 3 A cross-sectional view of the second heater assembly is shown;

[0121] Figure 4 A cross-sectional view of the third heater assembly is shown;

[0122] Figure 1 A longitudinal cross-sectional view of an aerosol generation system 100 is shown. The aerosol generation system 100 includes an aerosol generation device 150 and a cartridge 200. In this example, the aerosol generation system 100 is an electrically operated smoking system, commonly referred to as an electronic cigarette system.

[0123] The aerosol generating device 150 is portable and has a size equivalent to that of a conventional cigar or cigarette. Device 150 includes a battery 152 (e.g., a lithium iron phosphate battery) and a controller 154 electrically connected to the battery 152. Device 150 also includes two electrical contacts 156 and 158 electrically connected to the battery 152. This electrical connection is a wired connection and... Figure 1 Not shown in the image.

[0124] The cylinder 200 includes a first electrical contact 214 and a second electrical contact 216, an air inlet 202, an air outlet 204, and a heater assembly 300. An airflow path is defined between the air inlet 202 and the air outlet 204. The heater assembly 300 is positioned downstream of the air inlet 202 and upstream of the air outlet 204. The heater assembly 300 includes a liquid aerosol forming matrix, a retaining material 302, and a reservoir 303 for the liquid aerosol forming matrix. The retaining material 302 is in fluid communication with the reservoir 303 for the liquid aerosol forming matrix. The heater assembly 300 also includes a heating element 304. The first electrical contact 214 and the second electrical contact 216 are electrically connected to the heating element 304.

[0125] In this system 100, the liquid aerosol forming matrix comprises approximately 74% by weight glycerol, 24% by weight propylene glycol, and 2% by weight nicotine, though any suitable matrix may be used. Nicotine has a boiling point of approximately 247°C at atmospheric pressure, glycerol has a boiling point of approximately 290°C, and propylene glycol has a boiling point of approximately 188°C. Therefore, when this liquid aerosol forming matrix is ​​initially heated to form an aerosol, some systems may undesirably evaporate disproportionately large amounts of propylene glycol (which has the lowest boiling point of the matrix-forming compounds). This could result in an undesirable aerosol being delivered to the user, such as an aerosol comprising a smaller proportion of nicotine than desired. It could also undesirably alter the relative proportions of the compounds in the matrix over a longer period. The present invention can eliminate or at least reduce these undesirable effects.

[0126] Heating element 304 is configured to heat holding material 302 by passing an electric current along the length of heating element 304. Heating element 304 is formed of a material strip. The material strip has a cross-sectional area that gradually decreases along its length. The decreasing cross-sectional area of ​​the material strip provides a temperature gradient along the surface of holding material 302.

[0127] In this example, the material is mesh stainless steel. The material strip can be perforated.

[0128] In this example, the retaining material 302 is a porous ceramic capillary retaining material, which includes a large number of pores. Figure 1 In this process, the aerosol-forming matrix is ​​absorbed within the retaining material 302. The aerosol-forming matrix is ​​stored within the pores of the porous ceramic material.

[0129] In this example, the liquid aerosol forming matrix reservoir 303 includes a capillary material with a fibrous structure. In other embodiments, a liquid aerosol forming matrix reservoir or tank may be used. The capillary material is formed of polyester.

[0130] The reservoir 303, which forms a liquid aerosol matrix, can be adhered to the retaining material 302 by adhesive, or held in place by friction, or held in place by another suitable means.

[0131] exist Figure 1 In this embodiment, the aerosol generating device 150 is engaged with the cylinder 200. In this example, the cylinder 200 is engaged with the aerosol generating device 150 via the thread 206 of the cylinder 200, which mates with the corresponding thread 162 of the aerosol generating device 150.

[0132] In use, the user inhales through the air outlet 204 of the cylinder 200. Simultaneously, the user presses a button (not shown) on the aerosol generating device 150. Pressing this button sends a signal to the controller 154, which in turn supplies power from the battery 152 to the heating element 304 via the device's electrical contacts 156, 158 and the cylinder's electrical contacts 214, 216. This causes current to flow through the heating element 304, thereby resistively heating it. In other instances, an airflow sensor or pressure sensor is located in the cylinder 200 and electrically connected to the controller 154. The airflow sensor or pressure sensor detects that the user is inhaling through the air outlet 204 of the cylinder 200 and sends a signal to the controller 154 to supply power to the heating element 304. In these instances, the user therefore does not need to press a button to heat the heating element 304.

[0133] When the heating element 304 is resistively heated, regions of higher and lower temperatures are generated along the surface of the holding material 302. The lower-temperature regions can be generated in areas of the material strip forming the heating element 304 with a large cross-sectional area. The generation of these higher and lower-temperature regions causes the compounds forming the liquid aerosol matrix in the holding material 302, which have higher and lower boiling points respectively, to evaporate simultaneously. In this example, although... Figure 1 Not shown, but the air inlet is positioned closest to the heating element, having substantially the lowest resistance. The air outlet is positioned closest to the heating element, having substantially the highest resistance.

[0134] When a user draws air into the air inlet 202 of the cylinder 200 through the air outlet 204, air is drawn into the air inlet 202. This air then travels across the heater assembly 300, across the surface of the retaining material 302, and toward the air outlet 204. This airflow entrains vapor formed by the liquid aerosol forming matrix in the retaining material 302 heated by the heating element 304. This entrained vapor then cools and condenses to form an aerosol. This aerosol is then delivered to the user via the air outlet 204. As the liquid aerosol forming matrix in the retaining material 302 is heated, evaporated, and entrained in the airflow, the liquid aerosol forming matrix from the reservoir 303 travels into the retaining material 302. This aerosol forming matrix from the reservoir 303 effectively replaces the evaporated aerosol forming matrix. The liquid aerosol forming matrix from the reservoir 303 can be drawn into the retaining material 302 at least partially by capillary action. This is because the retaining material 302 is a capillary material having a fibrous or sponge-like structure.

[0135] Figure 2 A cross-sectional view of the heater assembly 300 is shown. The heating element 304 is formed of a material strip. The cross-sectional area of ​​the material strip gradually decreases along its length to provide a temperature gradient along the surface of the material. The heating element 304 is electrically connected to... Figure 2 Electrical contacts, not shown, are configured to supply power to resistively heat heating element 304. Figure 2 In the process, the width of the material strip of the heating element 304 gradually decreases. The minimum width of the heating element 304 is approximately 50% of the maximum width of the heating element. Therefore, the resistance of the heating element increases as the width of the material strip decreases to provide a temperature gradient along the surface of the retaining material 302.

[0136] Figure 3 A cross-sectional view of the second heater assembly 600 is shown. Heating elements 604 and 605 are formed of material strips. Heating elements 604 and 605 are configured to heat a holding material 602. In use, current flows along the length of the heating elements 604 and 605. Each heating element 604 and 605 is formed of a material strip. The material strip has a cross-sectional area that gradually decreases along its length. The decreasing cross-sectional area of ​​the material strip provides a temperature gradient along the surface of the holding material 602. The heating elements 604 and 605 are partially embedded within the holding material 602. Therefore, the cross-section of the holding material 602 is partially enclosed within a volume defined between the two heating elements 604 and 605. The heating elements 604 and 605 are electrically connected to... Figure 3Electrical contacts, not shown, are configured to supply power for resistance heating of heating elements 604 and 605. During resistance heating of heating elements 604 and 605, regions of higher and lower temperatures are generated within the holding material 602. The lower-temperature regions may be generated in areas where the material strip forming the heating elements 604 and 605 has a larger cross-sectional area. Furthermore, because the cross-section of the holding material 602 is enclosed within a volume defined between the two heating elements 604 and 605, the heating elements are positioned to further increase the temperature gradient as needed. For example, in… Figure 3 In this configuration, heating elements 604 and 605 are positioned such that the material strip region with the smallest cross-sectional area is positioned closer together than the ends of the material strip with the larger cross-sectional area. This provides an increased temperature gradient across the surface of the retaining material 602.

[0137] The generation of higher and lower temperature regions causes the compounds of the liquid aerosol forming matrix with higher and lower boiling points in the liquid aerosol forming matrix storage component 602 to evaporate simultaneously.

[0138] Figure 4 A cross-sectional view of the fourth heater assembly 900 is shown. The heating element 904 is formed of a material strip. The material strip is folded over itself to provide at least one overlapping portion. This provides a portion 915 of the heating element with a greater thickness compared to adjacent portions of the heating elements 905, 925. The portion 915 of the heating element with the greater thickness also has lower resistance compared to adjacent non-overlapping portions of the material strips 905, 925. The heating element 904 is electrically connected to... Figure 4 Electrical contacts, not shown, are configured to supply power to resistively heat heating element 904. In use, the portion 915 of the heating element with lower resistance is at a lower temperature and therefore provides less heat to the retaining material compared to the adjacent non-overlapping portions of the retaining material 905, 925. Thus, heating element 904 provides a temperature gradient along the surface of the retaining material. The lower-temperature portion along the retaining material corresponds to the portion 915 of the heating element with a greater thickness.

[0139] in addition, Figure 4 The material strip has a cross-sectional area that gradually decreases along its length. The width of the material strip also gradually decreases, thus providing a temperature gradient along its length. Figure 4 There are nine overlapping sections of material strips, but any number of overlapping sections can be selected. Therefore, the heating element does not have a gradually decreasing cross-sectional area.

[0140] For the purposes of this specification and the appended claims, unless otherwise indicated, all figures representing quantities, quantities, percentages, etc., shall be understood to be modified by the term "about" in all cases. Furthermore, all ranges include the disclosed maximum and minimum points, and include any intermediate ranges therein, which may or may not be specifically listed herein. Thus, in this context, the number A is understood as A ± 10% A. In this context, the number A can be considered to include a value within the general standard error for the measurement of the property modified by the number A. In some cases as used in the appended claims, the number A may deviate from the percentages listed above, provided that the amount of deviation from A does not significantly affect the fundamental and novel features of the claimed invention. Furthermore, all ranges include the disclosed maximum and minimum points, and include any intermediate ranges therein, which may or may not be specifically listed herein.

Claims

1. A heater assembly for an aerosol generation system, the heater assembly comprising: A liquid aerosol forming matrix comprising at least two compounds, the at least two compounds comprising a first compound and a second compound, wherein the first compound has a first boiling point and the second compound has a second boiling point; Includes a retaining material for the liquid aerosol forming matrix; as well as A heating element configured to heat the holding material by passing an electric current along the length of the heating element, wherein the heating element is formed of a material strip, wherein the cross-sectional area of ​​the material strip gradually decreases along the length of the material strip from the maximum cross-sectional area of ​​the material strip at a first end to the minimum cross-sectional area of ​​the material strip at a second end, to provide a temperature gradient along the surface of the holding material.

2. The heater assembly of claim 1, wherein the material strip is folded on itself to provide at least one overlapping portion, the at least one overlapping portion having a greater thickness and lower resistance compared to an adjacent non-overlapping portion of the material strip.

3. The heater assembly of claim 1 or 2, wherein the heating element comprises a first heating element material and a second heating element material, wherein the first heating element material is located at a first position along the length of the material strip, and the second heating element material is located at a second position along the length of the material strip, wherein the first heating element material has a first resistivity and the second heating element material has a second resistivity different from the first resistivity.

4. The heater assembly of claim 1 or 2, comprising a plurality of heating elements, wherein at least one of the plurality of heating elements provides a temperature gradient along the surface of the retaining material.

5. The heater assembly according to claim 1 or 2, wherein the material strip is perforated or is a mesh.

6. The heater assembly according to claim 1 or 2, wherein the retaining material is a porous ceramic capillary retaining material.

7. A cylinder for use in an aerosol generation system, the cylinder comprising a heater assembly according to any one of claims 1 to 6.

8. The cylinder of claim 7, comprising an air inlet and an air outlet, wherein an airflow path is defined between the air inlet and the air outlet, wherein air drawn from the air inlet to the air outlet flows through, passes through, or passes through the heating element.

9. The cylinder of claim 8, wherein the air inlet is positioned closest to the heating element with the lowest resistance, and the air outlet is positioned closest to the heating element with the highest resistance.

10. An aerosol generation system comprising a heater assembly according to any one of claims 1 to 6.

11. The aerosol generation system of claim 10, comprising an air inlet and an air outlet, wherein an airflow path is defined between the air inlet and the air outlet, wherein air drawn from the air inlet to the air outlet flows through, passes through, or passes through the heating element.

12. The aerosol generation system of claim 11, wherein the air inlet is positioned closest to the heating element with the lowest resistance, and wherein the air outlet is positioned closest to the heating element with the highest resistance.

13. The aerosol generation system of claim 11 or 12, wherein air in the airflow path passes through the surface of the retaining material, and the airflow path is in fluid contact with the aerosol forming matrix.

14. A method for heating an aerosol forming matrix within a heater assembly for an aerosol generation system, the heater assembly comprising: A liquid aerosol forming matrix comprising at least two compounds, the at least two compounds comprising a first compound and a second compound, wherein the first compound has a first boiling point and the second compound has a second boiling point; Includes a retaining material for the aerosol-forming matrix; And a heating element configured to heat the holding material, wherein the heating element is formed of a material strip, wherein the cross-sectional area of ​​the material strip gradually decreases along the length of the material strip; The method includes passing an electric current along the length of the material strip, such that the heating element provides a temperature gradient along the surface of the retaining material.

15. The method of claim 14, wherein the material strip is folded on itself to provide at least one overlapping portion, the at least one overlapping portion having a greater thickness and lower resistance compared to an adjacent non-overlapping portion of the material strip.

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