AEROSOL-GENERATING DEVICE WITH INTEGRAL HEATER ASSEMBLY

Abstract

An electrically heated aerosol-generating device is configured for use with a consumable cartridge including a storage portion containing an aerosol-forming substrate and having a fluid permeable internal surface surrounding an open-ended passage extending through the cartridge. The device includes a housing having a cavity for receiving the cartridge and a heater assembly positioned in the cavity. The heater assembly includes an electrically conductive hollow shaft portion connected to the housing and an electric heater positioned along the hollow shaft portion and having at least one heating element for heating the aerosol-forming substrate. The hollow shaft portion defines an airflow passage forming part of an airflow pathway through the device and is arranged to extend into the open-ended passage of the cartridge. The hollow shaft portion comprises a plurality of apertures, and the heating element is one or more narrow regions of the hollow shaft portion between adjacent apertures.

Claims

1. An electrically heated aerosol-generating device, comprising: a housing defining a cavity configured to receive a cartridge including a storage portion containing an aerosol-forming substrate and having a fluid permeable internal surface surrounding an open-ended passage extending through the cartridge; and a heater assembly positioned in the cavity of the housing, the heater assembly including a hollow shaft portion and at least one electric heater being integral with the hollow shaft portion, the hollow shaft portion connected to the housing and defining an airflow passage that is part of an airflow pathway through the electrically heated aerosol-generating device, the hollow shaft portion configured to extend into the open-ended passage when the cartridge is received in the cavity, the hollow shaft portion including a plurality of apertures, the at least one electric heater including at least one heating element configured to heat the aerosol-forming substrate when the cartridge is received in the cavity, the at least one heating element being one or more narrow regions of the hollow shaft portion between adjacent apertures of the plurality of apertures.

2. The electrically heated aerosol-generating device according to claim 1, wherein the at least one electric heater circumscribes the hollow shaft portion.

3. The electrically heated aerosol-generating device according to claim 1, wherein the at least one electric heater extends along substantially an entire length of the hollow shaft portion.

4. The electrically heated aerosol-generating device according to claim 1, wherein the at least one electric heater is in a form of a plurality of electric heaters spaced apart along a length of the hollow shaft portion.

5. The electrically heated aerosol-generating device according to claim 4, wherein the plurality of electric heaters are electrically isolated from each other to permit independent heating.

6. The electrically heated aerosol-generating device according to claim 5, wherein the hollow shaft portion is at least partially divided into a plurality of electrically isolated sections for coupling the plurality of electric heaters to an electrical power supply, the electrically isolated sections being electrically isolated from each other by one or more insulating gaps in the hollow shaft portion.

7. The electrically heated aerosol-generating device according to claim 1, wherein the hollow shaft portion has a piercing surface at a distal end of the hollow shaft portion, the hollow shaft portion configured to function as an elongate piercing member when the cartridge is received in the cavity.

8. The electrically heated aerosol-generating device according to claim 1, wherein the heater assembly is a single, unitary component.

9. The electrically heated aerosol-generating device according to claim 1, further comprising: an electrical power supply connected to the heater assembly.

10. An electrically heated aerosol-generating system comprising: a cartridge including a storage portion containing an aerosol-forming substrate, the storage portion having a fluid permeable internal surface surrounding an open-ended passage extending through the cartridge; and an aerosol-generating device including a housing and a heater assembly, the housing defining a cavity configured to receive the cartridge, the heater assembly positioned in the cavity of the housing, the heater assembly including a hollow shaft portion and at least one electric heater being integral with the hollow shaft portion, the hollow shaft portion connected to the housing and defining an airflow passage that is part of an airflow pathway through the aerosol-generating device, the hollow shaft portion configured to extend into the open-ended passage of the cartridge, the hollow shaft portion including a plurality of apertures, the at least one electric heater including at least one heating element configured to heat the aerosol-forming substrate, the at least one heating element being one or more narrow regions of the hollow shaft portion between adjacent apertures of the plurality of apertures.

11. The electrically heated aerosol-generating system according to claim 10, wherein the storage portion is compressible, and a diameter of the open-ended passage extending through the cartridge is less than an outer diameter of the hollow shaft portion.

12. The electrically heated aerosol-generating system according to claim 10, wherein the aerosol-forming substrate is an aerosol-forming liquid.

13. The electrically heated aerosol-generating system according to claim 12, wherein the fluid permeable internal surface of the storage portion includes a capillary wick configured to transport the aerosol-forming liquid to the heater assembly.

14. A kit for an electrically heated aerosol-generating system, the kit comprising: a plurality of cartridges, each of the plurality of cartridges including a storage portion containing an aerosol-forming substrate and having a fluid permeable internal surface surrounding an open-ended passage extending through each of the plurality of cartridges; and an aerosol-generating device including a housing and a heater assembly, the housing defining a cavity configured to receive one of the plurality of cartridges, the heater assembly positioned in the cavity of the housing, the heater assembly including a hollow shaft portion and at least one electric heater being integral with the hollow shaft portion, the hollow shaft portion connected to the housing and defining an airflow passage that is part of an airflow pathway through the aerosol-generating device, the hollow shaft portion configured to extend into the open-ended passage of one of the plurality of cartridges, the hollow shaft portion including a plurality of apertures, the at least one electric heater including at least one heating element configured to heat the aerosol-forming substrate, the at least one heating element being one or more narrow regions of the hollow shaft portion between adjacent apertures of the plurality of apertures.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0083] The various features and advantages of the non-limiting embodiments herein may become more apparent upon review of the detailed description in conjunction with the accompanying drawings. The accompanying drawings are merely provided for illustrative purposes and should not be interpreted to limit the scope of the claims. The accompanying drawings are not to be considered as drawn to scale unless explicitly noted. For purposes of clarity, various dimensions of the drawings may have been exaggerated.

[0084] FIG. 1 illustrates a longitudinal cross-section of an aerosol-generating system according to an example embodiment.

[0085] FIG. 2 illustrates a longitudinal cross-section of a consumable cartridge for use with the aerosol-generating system of FIG. 1.

[0086] FIG. 3A illustrates a perspective view of an example embodiment of a heater assembly for the aerosol-generating system of FIG. 1.

[0087] FIG. 3B illustrates an enlarged, partial side view of the heater assembly of FIG. 3A.

[0088] FIG. 4 illustrates an enlarged, partial perspective view of an example embodiment of a heater assembly for the aerosol-generating system of FIG. 1.

[0089] FIGS. 5A and 5B illustrate a method of inserting a consumable cartridge into the aerosol-generating device of the aerosol-generating system of FIG. 1.

[0090] FIG. 5C illustrates a longitudinal cross-section of the cartridge and heater assembly of the system of FIGS. 5A and 5B in which the aerosol-generating system is held in a tilted position.

DETAILED DESCRIPTION

[0091] It should be understood that when an element or layer is referred to as being “on,” “connected to,” “coupled to,” or “covering” another element or layer, it may be directly on, connected to, coupled to, or covering the other element or layer or intervening elements or layers may be present. In contrast, when an element is referred to as being “directly on,” “directly connected to,” or “directly coupled to” another element or layer, there are no intervening elements or layers present. Like numbers refer to like elements throughout the specification. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items.

[0092] It should be understood that, although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers, and/or sections should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer, or section from another region, layer, or section. Thus, a first element, component, region, layer, or section discussed below could be termed a second element, component, region, layer, or section without departing from the teachings of example embodiments.

[0093] Spatially relative terms (e.g., “beneath,” “below,” “lower,” “above,” “upper,” and the like) may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. It should be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as “below” or “beneath” other elements or features would then be oriented “above” the other elements or features. Thus, the term “below” may encompass both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

[0094] The terminology used herein is for the purpose of describing various embodiments only and is not intended to be limiting of example embodiments. As used herein, the singular forms “a,” “an,” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “includes,” “including,” “comprises,” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

[0095] Example embodiments are described herein with reference to cross-sectional illustrations that are schematic illustrations of idealized embodiments (and intermediate structures) of example embodiments. As such, variations from the shapes of the illustrations as a result, for example, of manufacturing techniques and/or tolerances, are to be expected. Thus, example embodiments should not be construed as limited to the shapes of regions illustrated herein but are to include deviations in shapes that result, for example, from manufacturing.

[0096] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which example embodiments belong. It will be further understood that terms, including those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

[0097] FIG. 1 is a schematic illustration of an aerosol-generating system 10 according to an example embodiment comprising an aerosol-generating device 100 and an aerosol-generating article in the form of a cartridge 200 (e.g., consumable cartridge).

[0098] The aerosol-generating device 100 comprises a housing 102 (e.g., main housing) containing a battery 104 and control electronics 106. The housing 102 also defines a cavity 108 into which the cartridge 200 is received. The aerosol-generating device 100 further includes a mouthpiece portion 110 including an outlet 112. In this example, the mouthpiece portion 110 is connected to the housing 102 by a screw fitting, but any suitable kind of connection may be used, such as a hinged connection or a snap fitting. The aerosol-generating device 100 further includes a heater assembly 300 comprising a piercing member 302 (e.g., elongate piercing member) in the form of a hollow shaft portion 304 connected to the housing 102 and a plurality of electric heaters 350 spaced apart along the length of the hollow shaft portion 304. The heater assembly 300 is positioned centrally within the cavity 108 of the aerosol-generating device 100 and extends along the longitudinal axis of the cavity 108. The hollow shaft portion 304 defines an airflow passage 306. Air inlets 114 are provided in the housing 102 upstream of the heater assembly 300 and are in fluid communication with the outlet 112 via the airflow passage 306.

[0099] As best seen in FIG. 2, the cartridge 200 comprises a storage portion 202 including a capillary wick 204 (e.g., tubular capillary wick) surrounded by a capillary material 206 (e.g., tubular capillary material) containing liquid aerosol-forming substrate. The cartridge 200 has a hollow cylindrical shape through which extends an internal passageway 208. The capillary wick 204 surrounds the internal passageway 208 so that the internal passageway 208 is at least partly defined by an inner surface of the capillary wick 204. The upstream and downstream ends of the cartridge 200 are capped by frangible seals 210, 212. The cartridge 200 further includes a sealing ring 214, 216 at each of the upstream and downstream ends of the internal passageway 208.

[0100] As best seen in FIGS. 3A and 3B, the hollow shaft portion 304 of the heater assembly 300 has a piercing surface 308 at its distal, or downstream end. In this example, the piercing surface 308 is formed by a sharp tip at the distal end of the hollow shaft portion 304. The hollow shaft portion 304 comprises a plurality of apertures 310 and partially divided into a plurality of electrically isolated sections 318 which are separated from each other by gaps 320 (e.g., insulating gaps). The plurality of apertures are arranged in a plurality of groups of apertures spaced apart along the length of the hollow shaft portion. In this example, the apertures are arranged in a first group 312 towards the proximal end of the hollow shaft portion 304 and a second group 314 towards the distal end of the hollow shaft portion 304. Each of the groups of apertures defines an electric heater 350. As shown in FIG. 3B, each electric heater 350 comprises a plurality of heating elements 352 defined by narrow regions of the hollow shaft portion between adjacent apertures 310. The heating elements 352 have a width 354 and the apertures have a width 356. The width 356 of the apertures may be selected so that, when in use, liquid aerosol-forming substrate is drawn in to the electric heater 350 by capillary action through the apertures 310. In the example shown in FIG. 3A, the first and second groups of apertures 310 are offset around the circumference of the hollow shaft portion 304. In other examples, two or more of the groups of apertures 310 may be aligned around the circumference of the hollow shaft portion 304.

[0101] The hollow shaft portion 304 is at least partially divided into a plurality of electrically isolated sections 318 which are electrically connected to the battery in the device. The heating elements 352 are connected at one end to one of the electrically isolated sections 318 and at the other end to a different one of the electrically isolated sections. In this manner, the electric heaters 350 are electrically connected to the device. The electrically isolated sections 318 may be electrically isolated from each other by the gaps 320. Thus, the electric heaters 350 may be electrically isolated from the each other to allow separate operation, control, or monitoring, without the need for separate electrical wiring for each heater. In this example, the gaps 320 are air gaps. That is, the gaps 320 do not contain insulating material. In other examples, one or more of the gaps 320 may be filled or partially filled with an electrically insulating material.

[0102] FIG. 4 illustrates a partial view of a heater assembly 400 according to an example embodiment. As with the heater assembly 300, the heater assembly 400 comprises an elongate piercing member in the form of a hollow shaft portion 404 defining an airflow passage 406 and having a plurality of apertures 410 along its length. However, unlike the heater assembly 300, the heater assembly 400 comprises a single electric heater 450 extending along substantially the entire length of the hollow shaft portion 404 and circumscribing the hollow shaft portion 404. The electric heater 450 again comprises a plurality of heating elements 452 defined by narrow regions of the hollow shaft portion 404 between adjacent apertures 410. However, in the case of heater assembly 400, the heating elements 452 are in a mesh pattern.

[0103] Referring to FIGS. 5A and 5B, insertion of the cartridge 200 into the aerosol-generating device 100 of the aerosol-generating system 10 will now be described.

[0104] To insert the cartridge 200 into the aerosol-generating device 100, and thereby assemble the aerosol-generating system 10, the first step is to remove the mouthpiece portion 110 from the housing 102 of the aerosol-generating device 100 and to insert the cartridge 200 into the cavity 108 of the aerosol-generating device 100, as shown in FIG. 5A. During insertion of cartridge 200 into the cavity 108, the piercing surface 308 at the distal end of the piercing member 302 breaks the frangible seal at the upstream end of the cartridge 200. As the cartridge 200 is inserted further into the cavity 108 and the piercing member 302 extends further into the internal passageway 208 of the cartridge, the piercing surface 308 engages with and breaks through the frangible seal at the downstream end of the cartridge 200 to create a hole in the frangible seal.

[0105] The cartridge 200 is then fully inserted into the cavity 108 and the mouthpiece portion 110 is replaced onto the housing 102 and engaged thereto to enclose the cartridge 200 within the cavity 108, as shown in FIG. 5B. When the cartridge 200 is fully inserted into the cavity 108, the holes in the frangible seals at the upstream and downstream ends of the cartridge 200 each have a diameter approximately equal to the outer diameter of the hollow shaft portion 304. The sealing rings at the upstream and downstream ends of the cartridge 200 form a seal around the hollow shaft portion 304. Together with the frangible seals this reduces or prevents leakage of liquid aerosol-forming substrate from the cartridge 200 and out of the aerosol-generating system 10. The cartridge 200 may be pressed fully into the cavity 108 before the mouthpiece portion 110 is replaced onto the housing 102. Alternatively, the cartridge 200 may be partially inserted into the cavity 108 and the mouthpiece portion 110 used to push the cartridge 200 into the cavity 108 until it is fully inserted.

[0106] As shown in FIG. 5B, when the cartridge 200 is fully inserted into the cavity 108 of the aerosol-generating device 100, an airflow pathway, shown by arrows in FIG. 5B, is formed through the aerosol-generating system 10. The airflow pathway extends from the air inlets 114 to the outlet 112 via the internal passageway 208 in the cartridge 200 and the airflow passage 306 in the heater assembly 300. As also shown in FIG. 5B, when the cartridge 200 is fully inserted, the electric heaters 350 are in fluid communication with the storage portion 202 of the cartridge 200 at the inner surface of the internal passageway 208.

[0107] In use, liquid aerosol-forming substrate is transferred from the storage portion 202 to the electric heaters 350 and may be held in the apertures of each electric heater 350 by capillary action. In this example, the outer diameter of the hollow shaft portion 304 is greater than the inner diameter of the internal passageway 208 of the cartridge 200 so that the storage portion 202 of the cartridge 200 is compressed by the hollow shaft portion 304. This ensures direct contact between the electric heaters 350 and the storage portion 202 to help transfer of liquid aerosol-forming substrate to the electric heaters 350. The battery supplies electrical energy to the heating elements of each electric heater 350. The heating elements heat up to vaporise liquid substrate in the capillary wick 204 to create a supersaturated vapour. At the same time, the liquid being vaporised is replaced by further liquid moving along the capillary wick 204 of the liquid storage portion 202 by capillary action. (This is sometimes referred to as “pumping action”.) When a negative pressure is applied to the mouthpiece portion 110, air is drawn through the air inlets 114, through the airflow passage of the hollow shaft portion 304, past the electric heaters 350, into the mouthpiece portion 110 and out of the outlet 112. The vaporised aerosol-forming substrate is entrained in the air flowing through the airflow passage of the hollow shaft portion 304 and condenses within the mouthpiece portion 110 to form an inhalable aerosol, which is carried towards the outlet 112.

[0108] The device may be operated by a manually-operated switch (not shown) on the aerosol-generating device 100. Alternatively, or in addition, the device may include a sensor for detecting a puff. When a puff is detected by the sensor, the control electrics control the supply of electrical energy from the battery to the electric heaters 350. The sensor may comprise one or more separate components. In some examples, the puff sensing function is performed by the heating elements of the heater and wick assemblies. For example, by measuring with the control electronics one or more electrical parameters of the heating elements and detecting a particular change in the measured electrical parameters which is indicative of a puff.

[0109] During use of the system, the distribution of liquid aerosol-forming substrate in the cartridge may change. For example, as the liquid aerosol-forming substrate in the storage portion is depleted during use, or where the system is held at an angle for a sufficient period of time. This change in the distribution of liquid aerosol-forming substrate may lead to differences in the amount of liquid in the capillary body of each electric heater and, consequently, the temperature of the heating element of each electric heater. This is discussed below in relation to FIG. 5C.

[0110] FIG. 5C shows a longitudinal cross-section of the cartridge 200 and heater assembly 300 of the aerosol-generating system following a period in which the system has been held in a tilted position. As shown, the remaining liquid 203 in the cartridge 200 has settled in the storage portion 202 at an angle to the heater assembly 300. As the electric heaters are spaced apart along the length of the cartridge 200, the amount of liquid aerosol-forming substrate in the region of storage portion 202 adjacent to the electric heaters is not uniform. In particular, the region of storage portion 202 at the upstream end of the cartridge adjacent to a first pair of electric heaters 360 is saturated with liquid aerosol-forming substrate, while the region of storage portion 202 adjacent to a second pair of electric heaters 370 midway along the length of the heater assembly 300 is only partially wet with liquid aerosol-forming substrate, and the region of storage portion 202 adjacent to a third pair of electric heaters 380 at the downstream end of the heater assembly 300 is dry. Consequently, the electric heaters 360, 370, 380 may be caused to run at different temperatures. As the electrical parameters of each electric heater, such as the electrical resistivity of the heating element , may vary as a function of the temperature, the distribution of the liquid aerosol-forming substrate or the remaining amount of liquid aerosol-forming substrate may be estimated by the control circuitry through measuring the electrical parameters of each electric heater. The control electronics is configured to separately measure one or more electrical parameters of each electric heater during use and to calculate an estimated remaining amount, or estimated distribution, of liquid aerosol-forming substrate in the cartridge based on differences in the measured electrical parameters from the electric heaters. Thus, the electric heaters function both as heaters and as sensors.

[0111] The device includes an indicator (not shown), such as a display or audio or haptic output, connected to the control circuitry, which may be used to convey information regarding the estimated remaining amount of liquid aerosol-forming substrate in the cartridge 200. When the estimated remaining amount falls below a threshold level, the electric circuitry may also be configured to operate the indicator to provide an alert and prompt the replacement of the cartridge. The control circuitry may also be configured to estimate the distribution of liquid aerosol-forming substrate in the cartridge based on differences in the measured electrical parameters from the electric heaters and to operate the indicator, when the estimated distribution suggests that system has been held at a particular angle for too long, to provide an alert that the orientation of the aerosol-generating device 100 should be altered, at least temporarily, to allow the liquid aerosol-forming substrate to be redistributed in the storage portion. In this, or other examples, the control circuitry may be configured to provide an alert about the estimated remaining amount or estimated distribution via a communication link with a separate device, such as a smartphone, swart-watch, tablet, desktop computer, or similar device.

[0112] In addition to detecting differences in electrical parameters in the electric heaters and calculating an estimated remaining amount, or estimated distribution, of liquid aerosol-forming substrate in the cartridge 200, the control electronics 106 is also configured to control the supply of electrical power to each of the electric heaters in response to the estimated remaining amount, or estimated distribution. In particular, where the measured electrical parameters indicate that one or more of the electric heaters is partially dry, the control electronics 106 is configured to reduce the supply of electrical energy to that electric heater. This allows the aerosol-generating system 10 to determine which of the electric heaters is in the best condition to generate aerosol in the most effective way. This allows adverse changes to the properties of aerosol generated by the aerosol-generating system 10, caused by variations in wetness and temperature across the electric heaters, to be minimised. It may also reduce energy consumption of the aerosol-generating system 10, and reduce the risk of damage to the electric heaters due to overheating. Where the electrical parameters indicate that one or more of the electric heaters is dry, the control electronics 106 is configured to reduce the supply of electrical energy to that electric heater to zero.

[0113] While a number of example embodiments have been disclosed herein, it should be understood that other variations may be possible. Such variations are not to be regarded as a departure from the spirit and scope of the present disclosure, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the following claims.