Flexible heaters and electronic devices

Abstract

The present invention relates to a heater for an aerosol generating device. The heater comprises a flexible electrically insulating substrate (10). The flexible electrically insulating substrate comprises a first portion and a second portion. The heater further comprises control electronics (12). The control electronics are disposed on the first portion of the flexible electrically insulating substrate. The heater further comprises a heating element (16) configured as an induction coil. The heating element is disposed on the second portion of the flexible electrically insulating substrate. A sensor element (48) is disposed on the fourth portion of the flexible electrically insulating substrate. The flexible electrically insulating substrate is rolled into a tube. The present invention further relates to an aerosol generating device and system.

Description

Technical Field

[0001] The present invention relates to a heater for an aerosol-generating device. The present invention further relates to an aerosol-generating device comprising a heater. The present invention further relates to a system comprising an aerosol-generating device and an aerosol-generating article comprising an aerosol-forming substrate. Background Art

[0002] It is known to provide an aerosol-generating device for generating an inhalable aerosol. Such a device can heat an aerosol-forming substrate to a temperature at which one or more components of the aerosol-forming substrate volatilize, without burning the aerosol-forming substrate. The vapor thus generated forms an aerosol when cooled before reaching the user's mouth. The aerosol-forming substrate can be provided as part of an aerosol-generating article. The aerosol-generating article can have a strip shape for inserting the aerosol-generating article into a cavity (e.g., a heating chamber) of the aerosol-generating device. A heater can be arranged around the heating chamber to heat the aerosol-forming substrate after the aerosol-generating article is inserted into the heating chamber of the aerosol-generating device. The heater can be a resistive heating element or an induction heater. Summary of the Invention

[0003] It is desirable to provide a heater for an aerosol-generating device that is easy to manufacture. It is desirable to provide a heater for an aerosol-generating device that can be manufactured at low cost. It is desirable to provide a heater for an aerosol-generating device that is compact. It is desirable to provide a heater for an aerosol-generating device that has few parts. It is desirable to provide a heater for an aerosol-generating device that is robust. It is desirable to provide a heater for an aerosol-generating device that is reliable. It is desirable to provide a heater for an aerosol-generating device that facilitates uniform heating of an aerosol-forming substrate received in a cavity of the aerosol-generating device. It is desirable to provide an aerosol-generating device that is easy to manufacture.

[0004] The above and further objects can be achieved by embodiments of the present invention, wherein a heater for an aerosol-generating device can be provided. The heater can include a flexible electrically insulating substrate. The flexible electrically insulating substrate can include a first portion and a second portion. The heater can further include control electronics. The control electronics can be disposed on the first portion of the flexible electrically insulating substrate. The heater can further include a heating element. The heating element can be disposed on the second portion of the flexible electrically insulating substrate. The flexible electrically insulating substrate can be rolled into a tube. By rolling the flexible electrically insulating substrate into the tube, the flexible electrically insulating substrate adopts a tubular shape.

[0005] Because the heating element and control electronics are provided on the heater's flexible, electrically insulating substrate, the heater is easier and less expensive to manufacture, as the heater and associated electronics can be provided on the flexible, electrically insulating substrate before it is rolled into a tube. Both the heating element and the control electronics can be printed on the flexible, electrically insulating substrate, for example, using metallic ink. During assembly, due to the substrate's flexible nature, the flexible, electrically insulating substrate, including the heating element and control electronics, can be formed into a desired shape, such as a tube, by rolling it.

[0006] The flexible electrically insulating substrate may be a flexible dielectric substrate. The flexible electrically insulating substrate may include polyimide. The flexible electrically insulating substrate may be composed of polyimide. The electrically insulating substrate may include any suitable material, and preferably is a material that can withstand high temperatures (such as temperatures in the range of 150 degrees Celsius to 250 degrees Celsius, or temperatures in the range of 250 degrees Celsius to 350 degrees Celsius) and rapid temperature changes. Examples of suitable materials are polyimide films, such as

[0007] Prior to assembling the heater, the flexible electrically insulating substrate may be flat. The first portion of the flexible electrically insulating substrate and the second portion of the flexible electrically insulating substrate may be integrally formed. In other words, the first portion of the flexible electrically insulating substrate and the second portion of the flexible electrically insulating substrate may be part of a single flexible electrically insulating substrate.

[0008] The first and second parts can be folded along a connecting portion connecting them so that the first and second parts of the electrically insulating substrate overlap. The connecting portion is preferably configured as a strip of flexible electrically insulating substrate connecting the first and second parts. The parts can then be joined together by applying an adhesive or PEEK and heat. The laminated substrate thus formed can be rolled into a tube. The aerosol generating device will be described in more detail below. A heater can be arranged around the cavity of the aerosol generating device to heat the aerosol-forming substrate of the aerosol-generating article inserted into the cavity.

[0009] One or both of the first portion of the flexible electrically insulating substrate and the second portion of the flexible electrically insulating substrate may be rectangular. One or both of the first portion of the flexible electrically insulating substrate and the second portion of the flexible electrically insulating substrate may have a square shape. One or both of the first portion of the flexible electrically insulating substrate and the second portion of the flexible electrically insulating substrate may have the same shape. The same shape of one or both of the first portion of the flexible electrically insulating substrate and the second portion of the flexible electrically insulating substrate may be selected in such a way as to achieve a spatially optimized arrangement of adjacent portions. Specifically, the individual portions of the flexible electrically insulating substrate may be folded and placed on top of each other before being rolled into a tube. If the individual portions have the same shape, this layered arrangement of the individual portions is simpler and makes optimal use of the available space.

[0010] The first portion of the flexible electrically insulating substrate may be connected to the second portion of the flexible electrically insulating substrate via a strip of the flexible electrically insulating substrate. The strip of the flexible electrically insulating substrate may be flat. The strip of the flexible electrically insulating substrate may be elongated. The strip of the flexible electrically insulating substrate may be narrower than one or both of the first portion of the flexible electrically insulating substrate and the second portion of the flexible electrically insulating substrate.

[0011] The heating element, located on the second portion of the flexible electrically insulating substrate, is electrically connected to control electronics, which may be located on the first portion of the flexible electrically insulating substrate. The connection between the heating element and the control electronics may be facilitated by electrical contacts and / or wires. The wires and / or electrical contacts may be arranged on a strip of the flexible electrically insulating substrate that connects the first portion of the flexible electrically insulating substrate to the second portion of the flexible electrically insulating substrate. At least one of the electrical contacts may be part of a thermocouple configured to measure temperature. The resistive heating track of the heating element, as described in more detail below, and one of the electrical contacts may be configured as a thermocouple. If the heating element includes at least two resistive heating tracks, the second resistive heating track together with the other electrical contact may be configured as a second thermocouple.

[0012] The first portion of the flexible electrically insulating substrate may be at least partially coaxially arranged around the outer periphery of the second portion of the flexible electrically insulating substrate. After being rolled into a tube, the first portion of the flexible electrically insulating substrate has a tubular shape. The first portion of the flexible electrically insulating substrate may have a hollow tubular shape.

[0013] The second portion of the flexible electrically insulating substrate may have a tubular shape. The second portion of the flexible electrically insulating substrate may have a hollow tubular shape. In one embodiment, the first portion and the second portion of the flexible electrically insulating substrate are laminated before being rolled into the tube.

[0014] The coaxial arrangement of the first portion of the flexible electrically insulating substrate relative to the outer periphery of the second portion of the flexible electrically insulating substrate can produce a compact heater. The compact heater can be arranged around the cavity of an aerosol-generating device for heating the aerosol-forming substrate of an aerosol-generating article received in the cavity.

[0015] The first portion of the flexible electrically insulating substrate may be arranged completely coaxially around an outer periphery of the second portion of the flexible electrically insulating substrate.

[0016] The heating element may be formed from one or more resistive heating tracks. The heating element may be comprised of resistive heating tracks. The resistive heating tracks may be provided on a flexible electrically insulating substrate. The resistive heating tracks may be printed on the flexible electrically insulating substrate, for example, using metallic ink. The resistive heating tracks may comprise a single resistive heating track. Alternatively, the resistive heating tracks may comprise at least two resistive heating tracks. The resistive heating tracks may function as resistive heaters.

[0017] The resistive heating track may have a temperature coefficient of resistance characteristic such that the resistive heating track may function as both a resistive heater and a temperature sensor.

[0018] The heating element, preferably in the form of a resistive heating track, is electrically connectable to a power supply. The heating element may comprise multiple sections. If the heating element is provided in the form of a resistive heating track, the resistive heating track may comprise multiple sections or a plurality of resistive heating tracks. Each section of the heating element may be individually connected to a power supply. This offers a number of advantages. Firstly, it allows different sections to be heated for different durations, depending on the properties of the aerosol-forming substrate, which may enhance the smoking experience. Secondly, it allows different sections to be heated at different temperatures, depending on the properties of the aerosol-forming substrate, which may also enhance the smoking experience. Thirdly, it allows specific sections of the heater to be activated at any one time. This allows only a portion of the aerosol-forming substrate to be heated at any one time.

[0019] The heater may include a power source. Preferably, the power source is configured as a battery. The power source may be located on the third portion of the flexible electrically insulating substrate. The power source may be configured as a lithium-ion battery. Alternatively, the power source may be a nickel-metal hydride battery, a nickel-cadmium battery, or a lithium-based battery such as a lithium-cobalt, lithium-iron-phosphate, lithium titanate, or lithium-polymer battery. Alternatively, the power source may be another form of charge storage device, such as a capacitor. The power source may require recharging and may have a capacity to store sufficient energy for one or more use experiences; for example, the power source may have sufficient capacity to continuously generate aerosol for a period of about six minutes or a multiple of six minutes. In another example, the power source may have sufficient capacity to provide a predetermined number of puffs or discontinuous heater activations.

[0020] The power source may be flat. The power source may be a flat battery. The power source may be flexible. The power source may be a flexible battery. The power source may be a flat and flexible battery. The power source may be provided as a flexible, flat sheet on the third portion of the flexible electrically insulating substrate. The third portion of the flexible electrically insulating substrate may be rectangular. The third portion of the flexible electrically insulating substrate may have a square shape. The third portion of the flexible electrically insulating substrate and one or both of the first portion and the second portion of the flexible electrically insulating substrate may have the same shape. The identical shapes of the portions of the flexible electrically insulating substrate may spatially optimize the arrangement of adjacent portions.

[0021] The third portion of the flexible electrically insulating substrate may be integrally formed with one or both of the first portion of the flexible electrically insulating substrate and the second portion of the flexible electrically insulating substrate. In other words, the first portion, the second portion, and the third portion of the flexible electrically insulating substrate may be separate parts of a single flexible electrically insulating substrate. The third portion of the flexible electrically insulating substrate may be connected to one or both of the first portion of the flexible electrically insulating substrate and the second portion of the flexible electrically insulating substrate. In a preferred embodiment, the third portion of the flexible electrically insulating substrate is attached to and positioned adjacent to the first portion of the flexible electrically insulating substrate.

[0022] The third portion of the flexible electrically insulating substrate may be rolled into a tube.In a preferred embodiment, the third portion of the flexible electrically insulating substrate is rolled into a tube together with the second portion of the flexible electrically insulating substrate to form a common tubular structure.

[0023] The second portion of the flexible electrically insulating substrate, including the heating element, can be at least partially coaxially arranged around the outer periphery of the third portion of the flexible electrically insulating substrate, including the power source. As described in more detail below, this arrangement is particularly preferred if the heating element is configured as an induction heating element. Alternatively, the heating element can be configured as a resistive heating element. In this case, the second portion of the flexible electrically insulating substrate, including the heating element, is preferably at least partially coaxially arranged within the third portion of the flexible electrically insulating substrate, including the power source.

[0024] The heating element may include an induction coil. The heating element may include at least two induction coils. The induction coils may be electrically connected to a power source. The controller electronics may be configured to control the supply of electrical energy from the power source to the induction coils. The induction coils may be configured to generate an alternating magnetic field.

[0025] The flexible electrically insulating substrate may include a fourth portion.The heater may further include a susceptor element disposed on the fourth portion of the flexible electrically insulating substrate.

[0026] The susceptor may be flat. The susceptor may be flexible. The susceptor may be provided as a flexible, flat sheet on the fourth portion of the flexible electrically insulating substrate. The fourth portion of the flexible electrically insulating substrate may be rectangular. The fourth portion of the flexible electrically insulating substrate may have a square shape. The fourth portion of the flexible electrically insulating substrate and one or more of the first portion of the flexible electrically insulating substrate, the second portion of the flexible electrically insulating substrate, and the third portion of the flexible electrically insulating substrate may have the same shape. The identical shapes of the portions of the flexible electrically insulating substrate may spatially optimize the arrangement of adjacent portions.

[0027] The fourth portion of the flexible electrically insulating substrate can be integrally formed with one or more of the first portion of the flexible electrically insulating substrate, the second portion of the flexible electrically insulating substrate, and the third portion of the flexible electrically insulating substrate. In other words, the first portion, the second portion, the third portion, and the fourth portion of the flexible electrically insulating substrate can be separate portions of a single flexible electrically insulating substrate. The fourth portion of the flexible electrically insulating substrate can be connected to one or more of the first portion of the flexible electrically insulating substrate, the second portion of the flexible electrically insulating substrate, and the third portion of the flexible electrically insulating substrate. In a preferred embodiment, the fourth portion of the flexible electrically insulating substrate is attached to and positioned adjacent to the second portion of the flexible electrically insulating substrate, at least before the second and fourth portions of the flexible electrically insulating substrate are positioned within the tube.

[0028] Generally speaking, a susceptor is a material capable of absorbing electromagnetic energy and converting it into heat when placed in an alternating magnetic field. If the susceptor is conductive, eddy currents are typically induced by the alternating magnetic field. If the susceptor is magnetic, another effect that often contributes to heating is often called hysteresis losses. Hysteresis losses primarily occur due to the movement of magnetic domain blocks within the susceptor, as their magnetic orientation aligns with the alternating magnetic field. Another effect that contributes to hysteresis losses is when magnetic domains grow or shrink within the susceptor. Generally, all these changes in the susceptor that occur at the nanometer scale or below are referred to as "hysteresis losses" because they generate heat within the susceptor. Therefore, if the susceptor is both magnetic and conductive, both hysteresis losses and eddy current generation contribute to susceptor heating. If the susceptor is magnetic but non-conductive, hysteresis losses are the sole means of heating the susceptor when the alternating magnetic field penetrates. According to the present invention, the susceptor can be conductive or magnetic, or both. The alternating magnetic field generated by one or more induction coils heats the susceptor, which then transfers the heat to the aerosol-forming substrate, causing aerosol formation. Heat transfer can be primarily by thermal conduction. This heat transfer is optimal if the susceptor is in close thermal contact with the aerosol-forming substrate.

[0029] The susceptor may be formed from any material that can be heated by induction to a temperature sufficient to generate an aerosol from the aerosol-forming substrate. Preferred susceptors may comprise or consist of ferromagnetic or ferrimagnetic materials, such as ferromagnetic alloys, ferritic iron, or ferromagnetic steel or stainless steel. Suitable susceptors may be or include aluminum. Preferred susceptors may be heated to a temperature exceeding 250 degrees Celsius.

[0030] The preferred susceptor is a metal susceptor, such as stainless steel. However, the susceptor material may also include or be made of the following: graphite; molybdenum; silicon carbide; aluminum; niobium; Inconel alloy (an austenite-based nickel-chromium superalloy); metallized films; ceramics such as zirconium oxide; transition metals such as iron, cobalt, nickel, or metalloid components such as boron, carbon, silicon, phosphorus, and aluminum.

[0031] Preferably, the susceptor material is a metallic susceptor material (metallic means metal in a non-oxide form, which is commonly referred to as a ceramic). The susceptor may also be a multi-material susceptor and may include a first susceptor material and a second susceptor material. In some embodiments, the first susceptor material may be arranged in close physical contact with the second susceptor material. The Curie temperature of the first susceptor material and / or the second susceptor material is preferably below the combustion temperature of the aerosol-forming substrate. The first susceptor material is preferably used primarily to heat the susceptor when the susceptor is placed in a fluctuating electromagnetic field. Any suitable material may be used. For example, the first susceptor material may be aluminum, or may be an iron-containing material such as stainless steel. The second susceptor material is preferably used primarily to indicate when the susceptor has reached a specific temperature, which is the Curie temperature of the second susceptor material. The Curie temperature of the second susceptor material can be used to regulate the temperature of the entire susceptor during operation. Suitable materials for the second susceptor material may include nickel and certain nickel alloys.

[0032] By providing a susceptor having at least a first susceptor material and a second susceptor material, heating of the aerosol-forming substrate and temperature control of the heating can be separated. Preferably, the second susceptor material is a magnetic material having a second Curie temperature that is substantially the same as the desired maximum heating temperature. That is, preferably, the second Curie temperature is substantially the same as the temperature to which the susceptor should be heated in order to generate an aerosol from the aerosol-forming substrate.

[0033] The term "Curie temperature" is generally understood to be the temperature at which a magnetic material loses its magnetic properties in the absence of an external magnetic field. Thus, the Curie temperature is the temperature at which a ferromagnetic or ferrimagnetic material undergoes a phase transition and becomes paramagnetic.

[0034] When an induction heating element is employed, the induction heating element may be configured as an external heater as described herein.If the induction heating element is configured as an external heating element, the susceptor element is preferably configured as a cylindrical susceptor at least partially surrounding the cavity or forming a side wall of the cavity.

[0035] The fourth portion of the flexible electrically insulating substrate may be rolled into a tube.

[0036] One or both of the second portion of the flexible electrically-insulative substrate including the heating element and the third portion of the flexible electrically-insulative substrate including the power source may be at least partially coaxially arranged around the outer periphery of the fourth portion of the flexible electrically-insulative substrate including the susceptor element. The fourth portion may be the innermost portion of the flexible electrically-insulative substrate after the flexible electrically-insulative substrate is rolled into a tube.

[0037] The final heater comprising all individual parts of the flexible electrically insulating substrate is preferably rolled into a tube.All individual parts of the flexible electrically insulating substrate are preferably at least partially, more preferably completely, coaxially aligned with each other.

[0038] If the flexible electrically insulating substrate of the final heater includes a first portion of the flexible electrically insulating substrate and a second portion of the flexible electrically insulating substrate, the second portion of the flexible electrically insulating substrate is preferably configured as the inner layer of the heater, and the first portion of the flexible electrically insulating substrate is preferably configured as the outer layer of the tubular heater. The heating element is arranged on the second portion of the flexible electrically insulating substrate, and in this embodiment, it is preferably configured as a resistive heater.

[0039] If the flexible electrically insulating substrate of the final heater further includes a third portion that includes a power source, the third portion is preferably disposed between the first portion of the flexible electrically insulating substrate and the second portion of the flexible electrically insulating substrate. In other words, the third portion is preferably disposed between the first portion and the second portion of the flexible electrically insulating substrate. Thus, the third portion may be sandwiched between the first portion and the second portion of the flexible electrically insulating substrate.

[0040] If the flexible, electrically insulating substrate of the final heater further includes a fourth portion comprising a susceptor, the heating element disposed on the second portion of the flexible, electrically insulating substrate is preferably configured as an induction coil. In this embodiment, the fourth portion comprising the susceptor is preferably disposed as an inner layer of the heater, while the second portion comprising the heating element is preferably configured to at least partially surround, and preferably completely surround, the fourth portion of the flexible, electrically insulating substrate. One or both of the first portion comprising the control electronics and the third portion comprising the power supply may be disposed between the inner fourth portion comprising the inductor and the second portion comprising the heating element.

[0041] The heater may include a finishing layer of a laminate material arranged to at least partially cover the heater. The finishing layer may be configured as an outer layer of the heater. The finishing layer may be configured to protect the heater. The finishing layer may be configured to completely cover the outer periphery of the heater. The finishing layer may be configured to enhance one or more of the heater's UV resistance, infrared resistance, brand printability, overall exterior design coloration, texture, mechanical resistance, chemical resistance, and other properties as desired. The finishing layer may be configured as a packaging material. The finishing layer may be wrapped around the heater.

[0042] The terms "inner" and "outer" refer to the spatial arrangement of the individual portions of the flexible electrically insulating substrate and the trim layer of the heater. The term "inner" refers to a lateral direction toward the central longitudinal axis of the heater. The term "outer" refers to a lateral direction away from the central longitudinal axis of the heater. The "inner" elements of the heater are arranged closer to the longitudinal center axis of the heater than the "outer" elements of the heater.

[0043] The present invention may also relate to a method for forming a heater. The heater may be formed from an initially planar, flat sheet of a flexible electrically insulating substrate. The planar, flat sheet of the flexible electrically insulating substrate may then be appropriately shaped. Specifically, the planar, flat sheet of the flexible electrically insulating substrate may be shaped such that a first portion of the flexible electrically insulating substrate is connected to a second portion of the flexible electrically insulating substrate via a strip of the flexible electrically insulating substrate. Optionally, one or both of a third and fourth portion of the flexible electrically insulating substrate may be formed. Subsequently, one or both of the heating elements may be arranged on the second portion, preferably printed on the second portion, and control electronics may be arranged on the first portion, preferably printed on the first portion. The heater is then rolled up, such that one or more of the first to fourth portions of the flexible electrically insulating substrate are rolled into a tube. During this process, one or more of the first to fourth portions of the flexible electrically insulating substrate are preferably at least partially, and more preferably completely, coaxially aligned with one another. For example, the second portion including the heating elements is first rolled up to form the tube. The strip connecting the second portion to the first portion including the control electronics may be flipped over so that the first portion overlies the second portion. The first portion may then be rolled around the second portion such that a tubular heater arrangement is achieved with an inner second portion and an outer first portion.

[0044] The first portion of the flexible electrically insulating substrate comprising the control electronics may have a thickness of between 0.025 mm and 3.50 mm, preferably 0.035 mm and 2.75 mm.

[0045] The second portion of the flexible electrically insulating substrate comprising the heating element may have a thickness between 0.02 mm and 3.50 mm, preferably between 0.035 mm and 2.7 mm.

[0046] The third portion of the flexible electrically insulating substrate comprising the power supply may have a thickness between 0.02 mm and 4.50 mm, preferably between 0.035 mm and 2.5 mm.

[0047] The present invention further relates to an aerosol-generating device comprising a cavity configured to receive an aerosol-generating article comprising an aerosol-forming substrate. The aerosol-generating device further comprises a heater as described herein. The heater is at least partially coaxially arranged around the outer periphery of the cavity.

[0048] The heater is configured to heat the aerosol-forming substrate of the aerosol-generating article when the aerosol-generating article is received in the cavity. To optimize heat transfer from the heater to the aerosol-forming substrate, the heater is at least partially coaxially arranged around the outer periphery of the cavity. In this way, heat can be transferred to the aerosol-forming substrate in a radially inward direction. Preferably, the heater is arranged completely coaxially around the outer periphery of the cavity.

[0049] The heater may comprise a power supply as described herein. Alternatively, the aerosol generating device may comprise a power supply, preferably a battery. The control electronics of the heater may be configured to control the supply of electrical energy from the power supply of the aerosol generating device to the heating element of the heater. As another alternative, the heater may comprise a power supply, and the aerosol generating device may comprise an additional power supply, preferably a battery. The control electronics of the heater may be configured to control the supply of electrical energy from the power supply of the heater and from the additional power supply of the aerosol generating device to the heating element of the heater. In addition to the control electronics of the heater, the aerosol generating device may comprise a controller. The control electronics of the heater may be configured to control the supply of electrical energy from the power supply of the heater to the heating element. The controller of the aerosol generating device may be configured to control the supply of electrical energy from the additional power supply of the aerosol generating device to the heating element of the heater.

[0050] The aerosol generating device may include a main body. One or both of an additional power source and a controller of the aerosol generating device may be arranged in the main body. The aerosol generating device may include a mouth end portion. The cavity may be arranged in the mouth end portion. The mouth end portion may be formed integrally with the main body. Alternatively, the mouth end portion may be configured to be removably attached to the main body. The mouth end portion may include a mouthpiece. The mouthpiece may be configured to cover the cavity. Exemplarily, the mouthpiece may be connected to the mouth end portion by a hinge connection. Alternatively, the mouthpiece may be removably attached to the mouth end portion of the aerosol generating device. As another alternative, no mouthpiece is provided, and the user draws directly on the proximal end of the aerosol generating article received in the cavity of the mouth end portion.

[0051] The heater may at least partially form a side wall of the cavity. Heat transfer may be optimized by the heater at least partially forming the side wall. The heater may completely form a side wall of the cavity.

[0052] As used herein, the term "aerosol-generating device" relates to a device that interacts with an aerosol-forming substrate to generate an aerosol. The aerosol-forming substrate may be part of an aerosol-generating article, such as a smoking article. The aerosol-generating device may be a smoking device that interacts with the aerosol-forming substrate of an aerosol-generating article to generate an aerosol that can be inhaled directly into the user's lungs through the user's mouth. The aerosol-generating device may be a holder. The device may be an electrically heated smoking device. The aerosol-generating device may include a housing, circuitry, a power supply, a heating chamber, and a heating element.

[0053] The present invention further relates to a system comprising an aerosol-generating device as described herein and an aerosol-generating article comprising an aerosol-forming substrate.

[0054] As used herein, the term "aerosol-generating article" refers to an article that includes an aerosol-forming substrate that is capable of releasing volatile compounds that can form an aerosol. For example, an aerosol-generating article may be a smoking article that generates an aerosol that can be inhaled directly into the user's lungs through the user's mouth. The aerosol-generating article may be disposable.

[0055] The aerosol-generating article may be substantially cylindrical in shape. The aerosol-generating article may be substantially elongated. The aerosol-generating article may have a length and a circumference substantially perpendicular to the length. The aerosol-generating article may be substantially rod-shaped. The aerosol-forming substrate may be substantially cylindrical in shape. The aerosol-forming substrate may be substantially elongated. The aerosol-forming substrate may also have a length and a circumference substantially perpendicular to the length. The aerosol-forming substrate may be substantially rod-shaped.

[0056] The aerosol-generating substrate may include an aerosol-forming agent. The aerosol-generating substrate preferably comprises: a homogenized tobacco material, an aerosol-forming agent, and water. Providing a homogenized tobacco material can improve aerosol generation, nicotine content, and flavor characteristics of the aerosol generated during heating of the aerosol-generating article. Specifically, the process for producing homogenized tobacco involves grinding tobacco leaves, which more effectively achieves the release of nicotine and flavor when heated.

[0057] Homogenized tobacco material is preferably provided in sheet form, and described sheet is folded, curled or cut into strip.In particularly preferred embodiment, sheet is cut into strip with width between about 0.2 millimeter and about 2 millimeters, more preferably between about 0.4 millimeter and about 1.2 millimeters.In one embodiment, the width of strip is about 0.9 millimeter.

[0058] Alternatively, the homogenised tobacco material may be formed into spheres using spheronisation.The average diameter of the spheres is preferably between about 0.5 mm and about 4 mm, more preferably between about 0.8 mm and about 3 mm.

[0059] The aerosol-generating substrate preferably comprises: between about 55% and about 75% by weight of homogenised tobacco material; between about 15% and about 25% by weight of aerosol-former; and between about 10% and about 20% by weight of water.

[0060] Samples of the aerosol-forming substrate were equilibrated at 22°C and 50% relative humidity for 48 hours before being measured.The moisture content of the homogenised tobacco material was determined using the Karl Fischer technique.

[0061] The aerosol-generating substrate may further comprise between about 0.1% and about 10% by weight of a flavorant.The flavorant may be any suitable flavorant known in the art, such as menthol.

[0062] Sheets of homogenised tobacco material for use in aerosol-generating articles including capsules may be formed by agglomerating particulate tobacco obtained by grinding or otherwise comminuting one or both of tobacco leaves and tobacco stems.

[0063] The sheet of homogenized tobacco material for use in an aerosol-generating article including a capsule may include one or more intrinsic binders that are endogenous to the tobacco, one or more extrinsic binders that are exogenous to the tobacco, or a combination thereof, to aid agglomeration of the particulate tobacco. Alternatively or in addition, the sheet of homogenized tobacco material may include other additives, including but not limited to tobacco and non-tobacco fibers, flavorings, fillers, aqueous and non-aqueous solvents, and combinations thereof.

[0064] Suitable external binders for inclusion in sheets of homogenized tobacco material for use in aerosol-generating articles, including capsules, are known in the art and include, but are not limited to, gums such as guar gum, xanthan gum, gum arabic, and locust bean gum; cellulosic binders such as hydroxypropyl cellulose, carboxymethyl cellulose, hydroxyethyl cellulose, methyl cellulose, and ethyl cellulose; polysaccharides such as starch; organic acids such as alginic acid; conjugate base salts of organic acids such as sodium alginate, agar, and 30 pectin; and combinations thereof.

[0065] The multiple reconstitution processes for producing the sheet material of homogenous tobacco material are known in the art. These processes include, but are not limited to: for example, a papermaking process of the type described in US-A-3,860,012; a casting or "cast leaf" process of the type described in US-A-5,724,998; a dough reconstitution (doughreconstitution) process of the type described in US-A-3,894,544; and an extrusion process of the type described in GB-A-983,928. Typically, the density of the sheet material of the homogenous tobacco material produced by extrusion and dough reconstitution processes is greater than the density of the sheet material of the homogenous tobacco material produced by casting processes.

[0066] Sheets of homogenised tobacco material for use in aerosol-generating articles including capsules are preferably formed by a casting process of the type which generally comprises casting a slurry comprising particulate tobacco and one or more binders onto a conveyor belt or other support surface, drying the cast slurry to form a sheet of homogenised tobacco material, and removing the sheet of homogenised tobacco material from the support surface.

[0067] Homogenized tobacco sheet material can use different types of tobacco to produce.For example, tobacco sheet material can use tobacco from multiple different tobacco varieties or from the tobacco of different areas (such as leaf or stem) of tobacco plant to form.After processing, sheet material has constant property and homogeneous fragrance.Can produce single homogenized tobacco material sheet with specific fragrance.In order to produce the product with different fragrance, need to produce different tobacco sheet materials.Some fragrances produced by mixing a large amount of different chopped tobaccos in conventional cigarettes may be difficult to replicate in single homogenized tobacco sheet.For example, Virginia tobacco and burley tobacco may need to process in different ways so that its individual fragrance reaches the best.May not replicate the specific mixture of Virginia tobacco and burley tobacco in single homogenized tobacco material sheet.Thus, aerosol generating matrix can comprise the first homogenized tobacco material and the second homogenized tobacco material.By combining two kinds of different tobacco material sheets in single aerosol generating matrix, can produce the novel mixture that can't be produced by single homogenized tobacco sheet.

[0068] The aerosol former preferably comprises at least one polyol. In a preferred embodiment, the aerosol former comprises at least one of: triethylene glycol; 1,3-butanediol; propylene glycol; and glycerol.

[0069] 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.

[0070] Example A: A heater for an aerosol-generating device, the heater comprising:

[0071] A flexible electrically insulating substrate, wherein the flexible electrically insulating substrate comprises a first portion and a second portion,

[0072] control electronics, wherein the control electronics are provided on a first portion of the flexible electrically insulating substrate, and

[0073] a heating element, wherein the heating element is provided on the second portion of the flexible electrically insulating substrate,

[0074] The flexible electrically insulating substrate is rolled into a tube.

[0075] Example B: The heater of Example A, wherein the first portion of the flexible electrically insulating substrate is at least partially coaxially arranged around an outer periphery of the second portion of the flexible electrically insulating substrate.

[0076] Example C: The heater of Example B, wherein the first portion of the flexible electrically insulating substrate is arranged completely coaxially around an outer periphery of the second portion of the flexible electrically insulating substrate.

[0077] Example D: The heater of any of the preceding examples, wherein the heating element comprises a resistive heating track, preferably wherein the heating element consists of a resistive heating track.

[0078] Example E: The heater of any of Examples A to C, wherein the heating element comprises an induction coil.

[0079] Example F: The heater of Example E, wherein the flexible electrically-insulative substrate includes a third portion, and wherein the heater further includes a power source disposed on the third portion of the flexible electrically-insulative substrate.

[0080] Example G: The heater of Example F, wherein the third portion of the flexible electrically insulating substrate is rolled into a tube.

[0081] Example H: The heater of Example G, wherein the second portion of the flexible electrically insulating substrate including the heating element is at least partially coaxially arranged around an outer periphery of the third portion of the flexible electrically insulating substrate including the power source.

[0082] Example I: The heater of any of Examples E to H, wherein the flexible electrically-insulative substrate includes a fourth portion, and wherein the heater further includes a susceptor element disposed on the fourth portion of the flexible electrically-insulative substrate.

[0083] Example J: The heater of Example I, wherein the fourth portion of the flexible electrically insulating substrate is rolled into a tube.

[0084] Example K: The heater of Example J, wherein one or both of the second portion of the flexible electrically insulating substrate including the heating element and the third portion of the flexible electrically insulating substrate including the power source are at least partially coaxially arranged around an outer periphery of the fourth portion of the flexible electrically insulating substrate including the susceptor element.

[0085] Example L: The heater of any of the preceding examples, wherein the heater comprises a trim layer of laminate material arranged to at least partially cover the heater.

[0086] Example M: An aerosol generating device comprising:

[0087] a cavity configured to receive an aerosol-generating article comprising an aerosol-forming substrate; and

[0088] The heater according to any of the preceding examples, wherein the heater is at least partially coaxially arranged around an outer periphery of the cavity.

[0089] Example N: An aerosol-generating device according to example M, wherein the heater at least partially forms a side wall of the cavity.

[0090] Example O: A system comprising an aerosol-generating device according to Example M or Example N and an aerosol-generating article comprising an aerosol-forming substrate.

[0091] Features described with respect to one embodiment may be equally applicable to other embodiments of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0092] The present invention will be further described, by way of example only, with reference to the accompanying drawings, in which:

[0093] Figure 1 shows a flexible electrically insulating substrate sheet of the heater prior to assembly;

[0094] Figure 2 shows a flexible electrically insulating substrate sheet during assembly of a heater;

[0095] Figure 3 Another embodiment of a flexible electrically insulating substrate sheet of a heater is shown prior to assembly;

[0096] Figure 4 Shows the heater after assembly Figure 3 Flexible electrically insulating substrate sheet;

[0097] Figure 5 shows a cross-sectional view of the final heater with multiple potential layers;

[0098] Figure 6 shows a schematic diagram of an aerosol generating device including a heater;

[0099] Figure 7 Another embodiment of an aerosol generating device is shown; and

[0100] Figure 8 Another embodiment of an aerosol generating device is shown. DETAILED DESCRIPTION

[0101] Figure 1 A flat sheet of flexible electrically insulating substrate is shown. The sheet is shown before the heater is assembled. The flexible electrically insulating substrate comprises a first portion of a flexible electrically insulating substrate 10. Ultimately, the heater's control electronics 12 are arranged on the first portion of the flexible electrically insulating substrate 10. The control electronics 12 are preferably printed on the first portion of the flexible electrically insulating substrate 10.

[0102] The flat flexible electrically insulating substrate sheet further comprises a second portion of the flexible electrically insulating substrate 14. A heating element 16 is arranged on the second portion of the flexible electrically insulating substrate 14. The heating element 16 is preferably printed on the second portion of the flexible electrically insulating substrate 14. The heating element 16 may be configured as a resistive heating track 18. Figure 1As shown in FIG, the heating element 16 may include at least two resistive heating tracks 18. The two resistive heating tracks 18 are electrically isolated from each other. The electrical isolation between the two heating tracks is facilitated by printing the two resistive heating tracks 18 spaced apart from each other on the second portion of the flexible electrically insulating substrate 14.

[0103] The heating element 16 is electrically connected to the control electronics 12. The electrical connection between the heating element 16 and the control electronics 12 is facilitated by electrical contacts 20. The electrical contacts 20 extend over a strip of flexible electrically insulating substrate 22. The strip of flexible electrically insulating substrate 22 is arranged between the first portion of the flexible electrically insulating substrate 10 and the second portion of the flexible electrically insulating substrate 14. The strip of flexible electrically insulating substrate 22 facilitates the connection between the portions 10, 14 and bridges the first portion of the flexible electrically insulating substrate 10 and the second portion of the flexible electrically insulating substrate 14.

[0104] Figure 1 The option of temperature measurement is further shown. In order to measure the temperature of the heater, a thermocouple 24 can be provided. The thermocouple 24 can include one of the resistive heating tracks 18 and one of the electrical contacts 20.

[0105] Figure 1 The dotted lines in FIG. 1 indicate that the heater is formed from a flexible electrically insulating substrate. The dotted lines indicate how the first portion of the flexible electrically insulating substrate 10 can be rolled into a tube. After the first portion of the flexible electrically insulating substrate 10 is rolled into a tube, the first portion of the flexible electrically insulating substrate 10 is rolled into a tube.

[0106] Figure 2 Shown from Figure 1 Assembly of the heater with a flat flexible electrically insulating substrate sheet is shown. Figure 1 A shows the second portion of the flexible electrically insulating substrate 14 rolled into a tube. Opposite sides of the second portion of the flexible electrically insulating substrate 14 can be folded over to be placed on top of each other, possibly including a spacer layer (not shown), and attached to each other by known processes, after which the "stack" or laminate of portions is rolled into a tube to form the tubular heater structure. The same principle rolling and attaching configuration can be applied to all portions of the flexible electrically insulating substrate. Figure 2 B shows an embodiment in which the first portion of the flexible electrically insulating substrate 10 is rolled into a tube similar to the second portion of the flexible electrically insulating substrate 14. In this embodiment, the first portion 10 and the second portion 14 are arranged spaced apart from each other along the longitudinal center axis 26 of the heater. Figure 2C shows an alternative arrangement in which the strip of flexible electrically insulating substrate 22 has been reversed, and the first portion of flexible electrically insulating substrate 10 is rolled around the second portion of flexible electrically insulating substrate 14. In this embodiment, the second portion of flexible electrically insulating substrate 14 is first rolled into a tube, and then the first portion of flexible electrically insulating substrate 10 is rolled around the second portion of flexible electrically insulating substrate 14. Thus, the second portion of flexible electrically insulating substrate 14 is configured as the inner portion, while the first portion of flexible electrically insulating substrate 10 is configured as the outer portion. As a preferred embodiment, both the first portion of flexible electrically insulating substrate 10 and the second portion of flexible electrically insulating substrate 14 are rolled together to form a tube. In this embodiment, the first portion of flexible electrically insulating substrate 10 and the second portion of flexible electrically insulating substrate 14 are first folded to be placed on top of each other. After being folded on top of each other, the first portion of flexible electrically insulating substrate 10 and the second portion of flexible electrically insulating substrate 14 are laminated together. Figure 2 D shows the opposite direction Figure 2 C's heater makes the strips of flexible electrically insulating substrate 22 clearly visible.

[0107] Figure 3 Another embodiment is shown in which the flat flexible electrically insulating substrate sheet further comprises a third portion of a flexible electrically insulating substrate 28. A power source 30 in the form of a battery is arranged on the third portion of the flexible electrically insulating substrate 28. The battery is constructed as a flexible battery that can be rolled into a tube together with the third portion of the flexible electrically insulating substrate 28. Figure 3 As shown in FIG, a power source 30 is electrically connected to the control electronics 12 of the first portion of the flexible electrically insulating substrate 10. The connection between the power source 30 and the control electronics 12 is facilitated by battery contacts 32. The battery contacts 32 are attached to contact areas 34 of the first portion of the flexible electrically insulating substrate 10.

[0108] Figure 4 Shows the use Figure 3 The heater after assembling the heater on the flexible electrically insulating substrate shown in FIG. Figure 1 and Figure 2 Compared to the embodiment shown in Figure 4 The heater shown in FIG also includes a third portion of a flexible electrically insulating substrate 28 that includes a power source 30. The third portion of the flexible electrically insulating substrate 28 is sandwiched between the first portion of the flexible electrically insulating substrate 10 and the second portion of the flexible electrically insulating substrate 14. The third portion of the flexible electrically insulating substrate 28 is arranged to be sandwiched between the first portion 10 and the second portion 14 of the flexible electrically insulating substrate.

[0109] Figure 5 A cross-sectional view of the final heater is shown. In addition to the portions 10, 14, 28 of the flexible electrically insulating substrate, Figure 5The heater shown in FIG includes a plurality of additional layers. All of these layers are optional. The individual layers and their functions are described below.

[0110] exist Figures 1 to 4 In the embodiment shown in , the heating element 16 is preferably configured as a resistive heater. Therefore, the second portion of the flexible electrically insulating substrate 14 including the heating element 16 is configured as an inner layer. Figure 5 In the embodiment shown, the heating element 16 is configured as an induction heating element 16. Therefore, the second portion of the flexible electrically insulating substrate 14 comprising the heating element 16 is arranged spaced apart from the innermost layer of the heater in a radially outward direction.

[0111] Figure 5 The heating element 16 in the embodiment includes an induction coil 42. The induction coil 42 is configured to receive an alternating current from a power source 30 and to generate an alternating magnetic field. The heater includes another layer comprising a susceptor element 48. The susceptor element 48 is configured as an inner layer of the heater. The susceptor element 48 may be disposed on a fourth portion of a flexible electrically insulating substrate as described herein. The alternating magnetic field generated by the induction coil 42 is configured to heat the susceptor element. A spacer layer 46 is disposed between the inner layer comprising the susceptor element 48 and the second portion of the flexible electrically insulating substrate 14 comprising the heating element 16. The spacer layer 46 electrically isolates the induction coil 42 from the susceptor element 48. Optionally, a consolidation cavity 54 wall layer 44 may be provided. The consolidation cavity 54 wall layer 44 may be arranged to form the cavity 54 of the aerosol generating device 50. The consolidation cavity 54 wall layer 44 may be part of the aerosol generating device 50 rather than part of the heater. The consolidation cavity 54 wall layer 44 may be disposed directly adjacent to the inner layer of the heater comprising the susceptor element. An inductive shielding layer 40 may be provided around the second portion of the flexible electrically insulating substrate 14 comprising the heating element 16. The inductive shielding layer 40 may have the function of a flux concentrator. Thus, the alternating magnetic field generated by the inductive coil 42 may be concentrated on the interior of the heater, in particular in the region of the susceptor element. Figure 5 In the embodiment shown in FIG, a third portion of the flexible electrically insulating substrate 28 including the power supply 30 is arranged around the inductive shielding layer 40. An insulating and mechanical protection layer 38 is arranged around this layer. A first portion of the flexible electrically insulating substrate 10 including the control electronics 12 is arranged around the insulating and mechanical protection layer 38. A finishing layer 36 is provided as a final outer layer. The finishing layer 36 is configured to protect the exterior of the heater. The finishing layer 36 may comprise a laminate material. If, as in Figure 5In the embodiment shown in FIG. 1 , induction heating is employed in the heater. Only the second portion of the flexible electrically insulating substrate 14 comprising the heating element 16 containing the induction coil 42, the inner layer comprising the susceptor element 48, and the first portion of the flexible electrically insulating substrate 10 comprising the control electronics 12 are mandatory. All other layers are optional. However, the other layers may be beneficial in optimizing the operation of the heater. Figure 5 Any of the optional layers described may be provided in the heater. Figure 5 The layers described can be similar to Figures 1 to 4 In other words, any of these layers can be provided on a flat flexible electrically insulating substrate sheet and subsequently rolled up to form the heater. Alternatively, any of these layers can be provided separately and arranged in a tubular heater.

[0112] Figure 6 An aerosol-generating device 50 is shown. An aerosol-generating article 52 comprising an aerosol-forming substrate can be inserted into a cavity 54 of the aerosol-generating device 50. A heater, as described herein, is arranged around the cavity 54 of the aerosol-generating device 50. A stopper 56 is arranged at the base of the cavity 54. The stopper 56 is configured to prevent the aerosol-generating article 52 from being over-inserted into the cavity 54.

[0113] Figure 7 An alternative configuration of an aerosol generating device 50 is shown. Figure 7 In the embodiment shown, the aerosol generating device 50 includes a body 58. A controller 60 and a main power source 62 in the form of a battery may be disposed within the body 58. The controller 60 is configured to control the supply of electrical energy from the main power source 62 to the heater. Figure 6 In contrast to the embodiment of FIG, energy is thus supplied by the main power source 62 of the body 58. As described herein, the heater itself may include the power source 30. Figure 6 In the embodiment shown, the aerosol generating device 50 therefore does not include a mains power supply 62 . Figure 7 The heater of the embodiment shown in FIG may include a power source 30 such that the additional power source 62 of the body 58 acts as a supplementary power source. However, preferably, the only power source is the main power source 62 of the aerosol generating device 50.

[0114] Figure 8 An embodiment is shown in which the primary power source is a cylindrical battery 62. This embodiment may be particularly useful with Figure 2B. A first portion of the electrically insulating substrate 10, including the control electronics 12, surrounds the main power source 62. The battery 62 is preferably the sole power source for the device. A second portion of the electrically insulating substrate 14, including the heating element 16, surrounds the cavity 54. An end wall 64 is provided at the distal end of the device. The end wall 64 may include electrical connections (not shown) to electrically connect the control electronics 12 to the battery 62. The outer surface of the end wall 64 may also include contacts (not shown) for recharging the battery 62 from an external power source such as a main power source. A sealing wall 66 is provided between the aerosol-generating article 52 inserted into the cavity 54 and the battery 62. The sealing wall 66 will prevent the aerosol-forming substrate from the aerosol-generating article 52 from reaching and contaminating the battery 62. In addition, in the event of a battery leak, the sealing wall 66 will prevent the receiving cavity 54 from being contaminated by undesirable chemical compounds. The sealing wall 66 may further act as a thermal insulator.

Claims

1. A heater for an aerosol generating device, the heater comprising: A flexible electrically insulating substrate, wherein the flexible electrically insulating substrate comprises a first portion, a second portion and a fourth portion, control electronics, wherein the control electronics are provided on the first portion of the flexible electrically insulating substrate, a heating element, wherein the heating element is provided on the second portion of the flexible electrically insulating substrate, wherein the heating element comprises an induction coil, and a susceptor element arranged on the fourth portion of the flexible electrically insulating substrate, wherein the first portion, the second portion and the fourth portion are separate portions of a single flexible electrically insulating substrate, and wherein the flexible electrically insulating substrate is rolled into a tube, and the first portion and the second portion of the flexible electrically insulating substrate are foldable to be placed on top of each other before being rolled into the tube. 2 . The heater of claim 1 , wherein the first portion of the flexible electrically insulating substrate is arranged to at least partially coaxially surround an outer periphery of the second portion of the flexible electrically insulating substrate. 3 . The heater according to claim 2 , wherein the first portion of the flexible electrically insulating substrate is arranged to completely coaxially surround an outer periphery of the second portion of the flexible electrically insulating substrate.

4. The heater according to any one of claims 1 to 3, wherein the flexible electrically insulating substrate comprises a third portion, and wherein the heater further comprises a power supply arranged on the third portion of the flexible electrically insulating substrate.

5. The heater of claim 4, wherein the third portion of the flexible electrically insulating substrate is rolled into a tube.

6. The heater of claim 5, wherein the second portion of the flexible electrically insulating substrate comprising the heating element is arranged at least partially coaxially around an outer periphery of the third portion of the flexible electrically insulating substrate comprising the power source.

7. The heater of claim 4, wherein the fourth portion of the flexible electrically insulating substrate is rolled into a tube.

8. The heater of claim 7 , wherein one or both of the second portion of the flexible electrically insulating substrate comprising the heating element and the third portion of the flexible electrically insulating substrate comprising the power source are arranged at least partially coaxially around an outer periphery of the fourth portion of the flexible electrically insulating substrate comprising the susceptor element.

9. A heater according to any one of claims 1 to 3, wherein the heater comprises a trim layer of laminate material arranged to at least partially cover the heater.

10. An aerosol generating device comprising: a cavity configured to receive an aerosol-generating article comprising an aerosol-forming substrate; as well as A heater according to any one of claims 1 to 9, wherein the heater is arranged at least partially coaxially around the outer periphery of the cavity.

11. An aerosol generating device according to claim 10, wherein the heater at least partially forms a side wall of the chamber.

12. A system having an aerosol-generating device according to claim 10 or claim 11 and an aerosol-generating article comprising an aerosol-forming substrate.

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