Patent Publication Number: US-11647795-B2

Title: Surface changing aerosol-generating system

Description:
This application is the § 371 U.S. National Stage of International Application No. PCT/IB2018/059152, filed 21 Nov. 2018, which claims the benefit of European Application No. 17210858.1, filed 28 Dec. 2017. 
     The present disclosure relates to aerosol-generating systems comprising aerosol-generating devices and aerosol-generating articles associated with the aerosol-generating devices, and particularly to aerosol-generating systems comprising devices and articles having a surface that changes shape in response to a parameter associated with the device or the article. 
     A number of aerosol-generating articles in which an aerosol-forming substrate, such as tobacco, is heated rather than combusted are known or have also been proposed in the art. In such articles, the aerosol is generated by heating the aerosol-forming substrate. Known heated aerosol-generating articles include, for example, articles in which an aerosol is generated by electrical heating. In use, volatile compounds are released from the aerosol-forming substrate when heated and are entrained in air drawn through the article. As the released compounds cool, they condense to form an aerosol that is inhaled by the consumer. Also known are smoking articles in which a nicotine-containing aerosol is generated from a tobacco material, tobacco extract, or other nicotine source, without combustion, and in some cases without heating, for example through a chemical reaction. 
     Such aerosol-generating articles are typically employed with aerosol-generating devices that include a power supply and suitable electrical components to, for example, heat the aerosol-forming substrate of the aerosol-generating article to an extent sufficient to generate an aerosol without combusting the substrate. 
     Other aerosol-generating devices, such as electronic cigarettes, are known to use aerosol-generating articles that include a liquid aerosol-forming substrate. The aerosol-generating article is typically a cartridge that contains the liquid aerosol-forming substrate. The device may include a power supply, such as a battery, control electronics, and an electrically operated aerosolizer. In some cases, the cartridge may include the electrically operated aerosolizer. A cartridge that includes both a supply of aerosol-forming substrate and an aerosolizer is sometimes referred to as a “cartomizer”. The aerosolizer may comprise a coil of resistive wire wound around an elongate wick soaked in liquid aerosol-forming substrate. Applying current to the resistive wire may heat the aerosol-forming substrate to form an aerosol that may be inhaled by a user. 
     Additional aerosol-generating devices may use aerosol-generating articles that include a gel that may be heated to generate an aerosol for inhalation by a user. Other aerosol-generating devices may use aerosol-generating articles that include a powder that may be inhaled by a user. 
     Such aerosol-generating devices and articles have different intrinsic states and parameters of which their users may wish to be informed. For example, a user may wish to be informed of the battery level of an aerosol-generating devices that employs a battery so that the user may plan when to charge the battery in relation to the time they plan to use the device. 
     Other useful information may be, for example, vapor or particle level or other parameters that may be adjusted with the use of such devices. 
     In addition, a user may find useful information regarding a consumable aerosol-generating article, such as flavour, brand, etc., in the device. Users usually know this information at the time of insertion or refill of the consumable article. However, after a while or if the user has several aerosol-generating devices, a reminder of a parameter of the consumable article that is presently inside an aerosol-generating device may be useful to a user. 
     With some aerosol-generating devices, information regarding the device or corresponding article may be displayed visually. For example, the device may include light emitting diodes (LEDs) that may be illuminated, for example, when the battery charge level is low. Devices may include a display, such as a liquid crystal display (LCD), that may provide information regarding a parameter of the device or corresponding article. 
     However, aerosol-generating devices are often put in pocket or bag, requiring a user to remove the device from their bag or pocket to see the visual cue regarding the status of the device. At times, it may be inconvenient to remove the device to check the status. In some instances, a user may wish to check the status of their device without making the aerosol-generating devices visible to other people who may be in the vicinity. 
     Some aerosol-generating devices vibrate to communicate status with users. However, vibrations may be disturbing and invasive when unexpected. Furthermore, vibrations typically are sent in short bursts which limit the time the information is available. If the aerosol-generating device is in, for example, a user&#39;s bag, there may be a low probability that a user would receive information from vibrations even if the user physically checks the aerosol-generating device from time to time, unless, by chance, the user places their hand on the device while the vibrations are occurring. Additionally, a user may become annoyed by repeated bursts of vibrations indicating a status of the device, if the user has already received the information. 
     Some aerosol-generating devices communicate status with users through the use of sound. Communication by sound may suffer from many of the drawbacks of communication by vibration. For example, the communicated information may be limited in time and not continuous, the information may not be discreet, or may become annoying if delivered after the user has already received the information, and the like. 
     It would be desirable to provide an aerosol-generating device capable of providing information to user that may be interpreted without vibration, sound, or purely visible cue. 
     In various aspects of the present invention there is provided an aerosol-generating system comprising at least one of an aerosol-generating device and an aerosol-generating article associated with the aerosol-generating device having an exterior surface capable of changing shape in response to a detected state of the aerosol-generating device or an aerosol-generating article associated with the device. Accordingly, there is also provided an aerosol-generating device having an exterior surface capable of changing shape in response to a detected state of the aerosol-generating device or an aerosol-generating article associated with the device. There is also provided an aerosol-generating article for use with an aerosol generating device, where the article has an exterior surface capable of changing shape in response a detected state of the aerosol-generating article or an aerosol-generating device associated with the article. The change in shape of the shape-changing element may cause a sufficient change in shape of at least one of an exterior surface of the device and an exterior surface of the article to provide tactile feedback to a user. Typically, the shape-changing element causes an exterior surface of at least one of the housing of the device and the housing of the article to change shape. 
     Any change in shape that may be detected by a user touching the device or feeling the device is sufficient to provide tactile feedback to the user. 
     The article comprises an article housing and an aerosol-forming substrate disposed in the article housing. The device comprises a device housing that defines a receptacle configured to receive the aerosol-generating article. The device further comprises control electronics disposed in the device housing. The device also comprises a sensor operably coupled to the control electronics and configured to detect a state of the device or an article received in the receptacle. In addition, at least one of the device and the article comprises a shape-changing element disposed on or in the housing. The control electronics are operably coupled to the shape-changing element and are configured to cause the shape-changing element to change shape in response to the state of the device or the article detected by the sensor. The change in shape or resulting shape of the exterior surface of at least one of the device and the article may provide a user of the device with information regarding the state of the device or an article associated with the device, such as an article received in the receptacle. 
     Various aspects or embodiments of the aerosol-generating devices described herein may provide one or more advantages relative to currently available or previously described devices that provide information regarding a state of the device or of an aerosol-generating article associated with the device. For example, by changing the shape of an exterior surface of the device, as opposed to providing a purely visual cue as with LEDs or LCDs, the user may be informed of the state of the device or associated article through tactile feedback, without having to view the article. By changing the shape of an exterior surface of the device, as opposed to a vibratory cue or an auditory cue, the user is not inconvenienced by repeated potentially unwanted signals of the state of the device or associated article. 
     Various aspects or embodiments of the aerosol-generating articles described herein may provide one or more advantages relative to currently available or previously described articles that provide information regarding a state of the article. For example, by changing the shape of an exterior surface of an aerosol-generating article, the article may provide information regarding the state of the article, such as the amount of aerosol-forming substrate remaining in the article or the number of puffs taken on the article. 
     Any suitable aerosol-generating device may include a shape-changing element to change a shape of an exterior or outer surface of the device to provide a user information regarding a state of the aerosol-generating device or an associated aerosol-generating article. The aerosol-generating device may be configured for use with any suitable aerosol-generating article, such as a cartridge comprising a liquid substrate, a cartridge comprising a solid substrate, a cartridge comprising a gel substrate, or a cartridge comprising a powder substrate. For example, the device may be an electronic cigarette-type device, a heat-not-burn type device, or the like. The device may be similar to Philip Morris International&#39;s I-QOS® aerosol-generating device which may receive a cartridge such as Philip Morris International&#39;s HEATSTICKS® or HEETS® articles, which contain an aerosol-forming substrate comprising tobacco. The I-QOS® aerosol-generating device heats the aerosol-forming substrate of the HEATSTICKS® or HEETS® articles to a temperature to sufficient to generate aerosol from the substrate without combusting the substrate. The device may be similar to NICOCIG® e-cigarette that may be used with any suitable cartridge comprising e-liquids or may be similar to Philip Morris International&#39;s MESH® system comprising e-liquid-containing cartridges. 
     Similarly, any suitable aerosol-generating article may include a shape-changing element to change a shape of an exterior or outer surface of the article to provide a user information regarding a state of the aerosol-generating article or the aerosol-generating device associated with the article. The aerosol-generating article may be any suitable aerosol-generating article, such as a cartridge comprising a liquid substrate, a cartridge comprising a solid substrate, a cartridge comprising a gel substrate, or a cartridge comprising a powder substrate. The aerosol-generating article may be configured for use with any suitable aerosol-generating device. 
     Regardless of the type of aerosol-generating device or aerosol-generating article, the shape-changing element may change shape in response to any suitable state of the aerosol-generating device or the associated aerosol-generating article. For example, the shape-changing element may change shape in response to a change in charge level (state of charge) of a power supply of the device, the type or aerosol-generating article received in the receptacle of the device, the amount of aerosol produced during use of the device, or the like. 
     The shape-changing element may change the shape of the exterior surface of the aerosol-generating device or the exterior surface of the aerosol-generating article in any suitable manner. For example, the shape-changing element may affect a global change in the shape of the surface of the device or the article, may affect a local change in the shape of the surface of the device or the article, may affect a texture of the surface of the device or the article, or the like. 
     The shape-changing element may be disposed on an outer surface of the article housing or on the outer surface of the device housing. 
     The change in shape of the exterior surface may provide a tactile cue to a user regarding the state of the device or an associated aerosol-generating article. The change in shape may also, in some instances, provide a visual cue to the user. Accordingly, in some situations the user may view the device to identify the state or may feel the device to identify the state, whichever is more convenient for the user at a given time. 
     The aerosol-generating system may comprise any suitable shape-changing element. The shape-changing element may comprise a shape-changing material. Any suitable shape-changing material may be used. For example, the shape-changing material may comprise a piezoelectric material, a shape memory alloy, a foam comprising gas bubbles, an electroactive polymer, or the like. A piezoelectric material and an electroactive polymer, for example, may change shape upon application of an electric current or voltage and return to its original shape when the current or voltage is no longer applied. A shape memory alloy and a foam containing gas bubbles may change shape upon application of heat or cold and return to its original shape during return to ambient temperature. 
     Any suitable piezoelectric material may be used as a shape-changing material. For example, piezoelectric crystals, ceramics, biomaterials, or the like may be used. Examples of piezoelectric materials that may be used include quartz, berlinite (AlPO 4 ), sucrose, Rochelle salt, topaz, tourmaline-group minerals, lead titanate (PbTiO 3 ), langasite (La 3 Ga 5 SiO 4 ), gallium orthophosphate (GaPO 4 ), lithium niobate (LiNbO 3 ), lithium tantalate (LiTaO 3 ), barium titanate (BaTiO 3 ), lead zirconate titanate (Pb[ZrxTi 1-x ]O 3  with 0≤x≤1), potassium niobate (KNbO 3 ), sodium tungstate (Na 2 WO 3 ), Ba 2 NaNb 5 O 5 , Pb 2 KNb 5 O 15 , zinc oxide (ZnO)-Wurtzite structure, bismuth ferrite (BiFeO 3 ), sodium niobate NaNbO 3 , bismuth titanate Bi 4 Ti 3 O 12 , sodium bismuth titanate (NaBi(TiO 3 ) 2 ), a bulk or nanostructured semiconductor crystal having non-central symmetry, such as the Group III-V and II-VI materials, polyvinylidene fluoride (PVDF), and organic nanostructures, such as self-assembled diphenylalanine peptide nanotubes, and the like. In some embodiments, the piezo electric material expands in volume upon application of an electric current or voltage and may return to a reduced original volume when the current or voltage is not applied. 
     Any suitable electroactive polymer may be used as a shape-changing material. Electroactive polymers may change shape in response to application of a current or voltage and return to their original shape when the current or voltage is no longer applied. Examples of electroactive polymers include dielectric electroactive polymers and ionic electroactive polymers. Examples of dielectric electroactive polymers include ferroelectric polymers, electrorestrictive graft polymers, and liquid crystal polymers. Examples of ionic electroactive polymers include conductive polymers, ionic polymer-metal composites, and stimuli-responsive gels. 
     The device may be configured in any suitable manner to apply a current or voltage to the piezoelectric material or the electroactive polymer. For example, the shape-changing element may include two electrodes between which the piezoelectric material or the electroactive polymer may be placed. The electrodes may be operably coupled to the control electronics of the device to control whether, how much, and when a voltage may be applied to the electrodes to affect a change in shape of the piezoelectric material or the electroactive polymer. In some embodiments, a current may be applied directly to the shape-changing material, such as a piezoelectric material, to affect a change in shape. Where the aerosol-generating article comprises the shape-changing element, the article and the device may comprise complimentary electrical contacts that are arranged to be connected when the aerosol-generating article is received by the device to electrically connect the piezoelectric material or the electroactive polymer to the power supply of the device. 
     Any suitable shape memory alloy may be used as a shape-changing material. In some embodiments, the shape memory allow is a two-way shape memory alloy. Two-way shape memory alloys are materials that can take two different shapes: one shape at lower temperatures; and another shape at higher temperatures. The shape of a two-way shape memory alloy may depend on temperature, which means that a change in temperature will cause changes in the shape of the alloy. The temperatures within the temperature range during which a shape memory alloy changes shape are called the transformation temperatures of the alloy. There is a hysteresis associated with this phase transformation. The magnitude of the hysteresis varies from one alloy system to another, and has typical values ranging from 20° C. to 40° C. The transformation temperatures may be adjusted according to the kind of alloy used, and the transformation temperatures could be chosen from −100 to 100° C. In some embodiments, the shape memory alloy has a transformation temperature in a range from about 40° C. to about 70° C. 
     Suitable shape memory alloys include noble-metal based shape memory alloys, Cu-based shape memory alloys, Fe-based shape memory alloys, Ni—Ti-based shape memory alloys, and the like. In some embodiments, the shape-changing material comprises a titanium-nickel-copper (TiNiCu) shape memory alloy, which alloys may exhibit good fatigue performance allowing a million, ten million, or more, shape transformation cycles. 
     Any suitable foam comprising gas bubbles may be used as a shape-changing material. The foam may expand in volume when heated and may return to its original volume when cooled to ambient temperature. The foam may be a hermetic foam. The foam may be hermetic such that the gas bubbles may be retained in the foam, or the foam may be placed in flexible hermetic package. The gas bubbles may be air or any other suitable gas that readily expands when heated. The foam may comprise any suitable material, such as polyurethane. 
     The shape-changing element may comprise a heating element to heat the shape memory alloy or the foam to cause the shape memory alloy of the foam to change shape or expand. The shape memory alloy or the foam may be placed in contact or in proximity to a heating element. 
     The heating element may comprise, for example, a resistive wire or mesh. The shape memory alloy or foam may be on a resistive substrate, which serves as the heating element. The heating element may be operably coupled to the control electronics of the device to control whether, how much, and when the heating element is heated to cause the change in shape or volume of the shape memory alloy or the foam. 
     In some embodiments, a currently may be directly applied to the shape-changing material, such as a shape memory alloy, which may serve as a resistor and be heated by the Joule effect. This heating may affect a change in shape of the shape-changing material. 
     Activation of the shape-changing element by application of heat may result in a rapid change in shape. However, loss of heat following a ceasing of the application of the heat may occur over a longer period of time, as the heat is transferred to, for example, the external environment. Such a situation may be useful when using a shape memory alloy that will not change shape until the transition temperature is reached. A small or minimal amount of energy may be applied to heat the shape memory alloy to a temperature above the transition temperature, and the resulting shape may be retained for a relatively long period of time until the heat dissipates. Accordingly, an extended shape change may be accomplished with a small or minimal energy input. 
     The shape-changing element, or a portion thereof, may be positioned on or in the housing. In some embodiments, the shape-changing element is positioned between a base layer and an exterior layer of the housing. The base layer may provide structural rigidity to the housing. The exterior layer may be sufficiently flexible to accommodate a change in shape when the shape of the shape-changing element changes. The exterior layer may retain the shape-changing element. The exterior layer may provide, or aid in providing, a hermetic barrier for foam with gas bubbles. The exterior layer may be a coating disposed on the base layer. The exterior layer may be resilient and biased towards a retracted state. The exterior layer may serve as a heat shield to prevent excessive heat transfer from, for example, a resistive element of the shape-changing element to a user touching the housing. In some embodiments, the housing includes an additional heat shield layer between the base layer and the exterior layer. The heat shield layer may also serve to conduct heat over a large area to facilitate cooling of the shape-changing element when a heating element is no longer activated. 
     The housing may comprise any suitable base layer. For example, the base layer of the housing may be formed of any suitable metallic material, rigid plastic material, or combinations thereof. Examples of suitable metallic materials include stainless steel, aluminium, and the like. Examples of suitable rigid plastic materials include high density polyethylene, polycarbonate, polyamides, polypropylene, and the like. 
     The housing may include any suitable exterior layer. In some embodiments, the base layer is the exterior layer of the housing. If present, examples of suitable exterior layers include rubbers, thermoplastic elastomers, thermoplastic vulcanizates, thermoplastic urethane, and flexible polyvinyl chloride (PVC). For example, the exterior layer may comprise polyurethane, low density polyethylene, SANTOPRENE® thermoplastic vulcanizate, silicone, PVC including plasticizers, polyethylene propylene diene, and the like. 
     Any suitable material may be employed in an optional heat shield layer. Suitable materials include thermally conductive polymer materials and metallic foils. Examples of thermally conductive polymeric materials may include polymers containing graphite fibres or metallic particles as additives. Examples of suitable metallic foils include aluminium, copper, and tin foils. 
     The shape-changing element may include a movable part. The movable part may, in some embodiments, not change shape, but rather move when the shape-changing material changes shape. The movable part may be disposed on or operably coupled to the shape-changing material such that, when the shape-changing material changes shape, the movable part moves. The movable part may be shaped and sized to provide visual or tactile cues to a user. The moveable part may have circular, triangular, square, or other suitably shaped surfaces. In some instances, the movable part may have a surface in the shape of a letter, word, or symbol. The movable part may correspond to dots of a Braille alphabet. The Braille alphabet uses 2 columns having each of 3 or 4 pins. The movable part may be positioned between a base layer and an exterior layer of the housing of the article and the device. The moveable part may be formed of any suitable material. For example, the movable part may be formed of a rigid plastic, metal, or combinations thereof. 
     The housing of the aerosol-generating device may define a receptacle for receiving an aerosol-generating article. The receptacle is sized and shaped to receive at least a portion of an appropriate aerosol-generating article. The aerosol-generating article may comprise a container configured to be received by the receptacle of the housing and may comprise an aerosol-forming substrate disposed in the container. 
     Any suitable container may be employed. In some embodiments where the aerosol-forming substrate is a solid substrate, the container may include a wrapper that circumscribes the aerosol-forming substrate. For example, the wrapper may comprise a plug wrap, cigarette paper, or the like. In some embodiments where the aerosol-forming substrate is a liquid substrate, the container may include a plastic or metallic housing to contain the liquid. 
     Information regarding one or both of the aerosol-generating article and the aerosol-forming substrate in the article may be included an element disposed in, on or around the container. For example, an RFID tag may be placed on the container or an electrical circuit comprising an electrical contact may be disposed on the container. The aerosol-generating device may include an RFID reader or an electrical contact, for example in the receptacle, for electrical connection with the contact of the container. The RFID reader or electrical contact may be operably coupled to control electronics of the aerosol-generating device to receive information regarding one or both of the aerosol-generating article and the aerosol-forming substrate in the article. The sensor may comprise the RFID reader or electrical contact. 
     The housing of the aerosol-generating device may define a device interior in which at least one of the control electronics and a power supply may be disposed. 
     The control electronics may be provided in any suitable form and may, for example, include a controller or a memory and a controller. The controller may include one or more of an Application Specific Integrated Circuit (ASIC) state machine, a digital signal processor, a gate array, a microprocessor, or equivalent discrete or integrated logic circuitry. Control electronics may include memory that contains instructions that cause one or more components of the circuitry to carry out a function or aspect of the control electronics. Functions attributable to control electronics in this disclosure may be embodied as one or more of software, firmware, and hardware. The control electronics may be operably coupled to the power supply. 
     The aerosol-generating device may comprise any suitable power supply. For example, a power supply of an aerosol-generating device may be a battery, or set of batteries. The batteries or power supply unit may be or more of rechargeable, removable, and replaceable. Any suitable battery may be used. 
     The control electronics may be configured to regulate the power supply. The power may be supplied to the shape-changing element, or an appropriate portion of the shape-changing element, in any suitable manner, such as in the form of electrical current or a voltage differential, to cause the shape-changing element to change the shape of at least one of the article and the device. The shape-changing element or portion thereof may be coupled to the control electronics through a multiplexor if the system includes a plurality of shape-changing elements. The use of a multiplexor may simplify construction of the device by avoiding the need for separate lines to be run the entire distance to each shape-changing element or portion thereof. 
     The control electronics and power supply may also control the basic operation of the aerosol-generating device. For example, if the aerosol-generating device operates by heating the aerosol-forming substrate to generate an aerosol for inhalation by a user, the control electronics may be operably coupled to a heating element to control the heating of the aerosol-forming substrate. The device or article may include a resistive heating element operably coupled to the control electronics and power supply. In some embodiments, the device may include an inductive heating coil to inductively heat a susceptor material in contact with, or in proximity to, the aerosol-forming substrate. 
     The control electronics may include a communication module or suitable circuitry for communicating with an external device, such as a computer or smartphone. The communication may be wireless or wired. At least a portion of the control of the shape-changing element may be programmed by a user of the external device. For example, the way in which the shape-changing elements change a shape of the device may be controlled by the user. A user program the control electronics to associate a particular shape change with a parameter of the device or associated article, allowing the user to personalize the shape change notification. The manufacturer of the device may develop an application that may be run on the external device to allow the external device to interact with, and optionally program, the control electronics as appropriate or desired. 
     The control electronics may be operably coupled to one or more sensors configured to detect a state of the device or an aerosol-generating article associated with the device. The control electronics may activate a shape-changing element to change the shape of at least one of an external surface of the housing of the device and an external surface of the housing of the article in response to a state detected by a sensor. The aerosol-generating device may comprise any suitable number and type of sensor to identify a status of the device. The type of sensor employed may vary depending to the state of the device or associated aerosol-generating article to be detected. 
     For example, the device may comprise a sensor configured to detect the charge level or state of charge of a battery or other suitable power supply disposed in the housing. Any suitable sensor may be used to detect the charge level of a battery. For example, the battery charge level sensor may include an ammeter, a voltmeter, a resistance meter, or the like. 
     The device may comprise a sensor to detect parameters associated with an aerosol-generating article. For example, the type or aerosol-generating article, the brand of aerosol-generating article, the flavour of material in the aerosol-generating article, the amount of aerosol-forming substrate remaining, or the like may be detected. The device may obtain Information regarding the aerosol-generating article in any suitable manner. For example, a direct electrical connection between the control electronics of the device and the aerosol-generating article may be formed with the cartridge when the cartridge is received in the receptacle defined by the housing of the device. Information regarding the article may be transmitted to the control electronics through the direct electrical connection. For example, an interior of the receptacle and an exterior of the aerosol-generating article may include contacts for direct electrical connection of the control electronics of the device to the article. In some embodiments, information regarding the article may be transmitted wirelessly to the device. In some embodiments, the range of wireless transmission is limited so that only information from an article received by the device, as opposed to an article in general proximity to the device, is transmitted to the device. In some examples, the aerosol-generating article comprises an RFID tag and the device comprises an RFID reader. 
     In some embodiments, the sensor may comprise any suitable optical sensor to detect a visible indicator, such as a barcode, provided on an exterior surface of an aerosol-generating article. The sensor may be arranged to detect a visible indicator on an article when the article is received in the receptacle of the device. 
     The device may comprise a sensor configured to detect any suitable operation parameter of the device. For example, the amount of aerosol or particulate matter produced as the device is in use may be monitored. Any suitable sensor may be used. For example, the sensor may comprise any suitable optical sensor to detect aerosol or particulate matter concentration through, for example, light scattering or absorption. In some embodiments, a sensor configured to measure capacitance or resistance across a passage through which the aerosol or particulate matter flows may be used to detect concentration of the aerosol or particulate matter generated during use of the device. 
     In another aspect of the present invention, there is provided an aerosol-generating device comprising: a housing defining a receptacle configured to receive an aerosol-generating article; control electronics disposed in the housing; and a sensor operably coupled to the control electronics. The sensor is configured to detect a state of the device or the article when the article is received in the receptacle. The system further comprises a shape-changing element disposed on or in the housing, and the control electronics are operably couplable to the shape-changing element and are configured to cause the shape-changing element to change shape in response to the state of the device or the article detected by the sensor. 
     In another aspect of the present invention, there is provided an aerosol-generating article for use with an aerosol-generating device, the article comprising: a housing; an aerosol-forming substrate disposed in the housing; and a shape-changing element disposed on or in the housing. The shape-changing element is operably couplable to control electronics of an aerosol-generating device to cause the shape-changing element to change shape. 
     Any features described above in relation to one aspect may also be applicable to other aspects of the invention. 
    
    
     
       Reference will now be made to the drawings, which depict one or more aspects described in this disclosure. However, it will be understood that other aspects not depicted in the drawings fall within the scope and spirit of this disclosure. Like numbers used in the figures refer to like components, steps and the like. However, it will be understood that the use of a number to refer to a component in a given figure is not intended to limit the component in another figure labeled with the same number. In addition, the use of different numbers to refer to components in different figures is not intended to indicate that the different numbered components cannot be the same or similar to other numbered components. The figures are presented for purposes of illustration and not limitation. Schematic drawings presented in the figures are not necessarily to scale. 
         FIG.  1    is a schematic sectional view of an aerosol-generating device and article that may be used in accordance with the present invention 
         FIG.  2 A  is a schematic sectional view of disconnected parts and cover of an aerosol-generating device and associated aerosol-generating article that may be used in accordance with the present invention. 
         FIGS.  2 B-C  are schematic perspective views of an example of an aerosol generating system shown in  FIG.  2 A .  FIG.  2 B  shows the parts connected and the cover removed.  FIG.  2 C  shows the system with the cover secured in place. 
         FIGS.  3 A- 3 B  are schematic sectional views of an aerosol-generating device having a shape-changing element in an inactivated state ( FIG.  3 A ) and an activated state ( FIG.  3 B ). 
         FIGS.  4 A- 4 B  are schematic block diagrams of an aerosol-generating device having a shape-changing element in an inactivated state ( FIG.  4 A ) and an activated state ( FIG.  4 B ). 
         FIGS.  5 A- 5 B  are schematic block diagrams of an aerosol-generating device having a shape-changing element in an inactivated state ( FIG.  5 A ) and an activated state ( FIG.  5 B ). 
         FIGS.  6 A- 6 B  are schematic sectional views of a portion of a housing and a shape-changing element disposed in the housing. In  FIG.  6 A  the shape-changing element is in an inactivated state. In  FIG.  6 B  the shape-changing element is in an activated state. 
         FIGS.  7 A-B  are schematic top plan views of an embodiment of the portion of a housing depicted in  FIGS.  6 A-B .  FIG.  7 A  corresponds to  FIG.  6 A , in which the shape-changing element is in an inactivated state.  FIG.  7 B  corresponds to  FIG.  6 B , in which the shape-changing element is in an activated state. 
         FIGS.  8 A-B  are schematic sectional views of an aerosol-generating system including an aerosol-generating device and an associated aerosol-generating article having a shape-changing element in an inactivated state ( FIG.  8 A ) and an activated state ( FIG.  8 B ). 
         FIG.  9    is a schematic block diagram of an aerosol-generating system including an aerosol-generating device and an associated aerosol generating article having a shape-changing element in an inactivated state. 
     
    
    
       FIG.  1    illustrates a system that includes an aerosol-generating device  200  and associated aerosol-generating article  100  in accordance with an embodiment the present invention. The device  200  includes a housing  210  defining the receptacle  220 , which is configured to receive the aerosol-generating article  100 . The device  200  also includes an elongate heating element  230  extending into the receptacle  220 . The heating element  230  may comprise an electrically resistive heating component. The receptacle  220  has an open end through which the aerosol-generating article  100  may be inserted. The receptacle  220  has a closed end, which the aerosol-generating article  100  may abut when inserted into the receptacle  220 . In addition, the device  200  includes a power supply  240  and control electronics  250  disposed in an interior of the housing  210 . The power supply  240  and control electronics  250  cooperate to control heating of heating element  230 . Preferably, the control electronics  250  are configured to cause the heating element to heat to an extent sufficient to cause aerosol generation from an aerosol-forming substrate of an aerosol-generating article used with the device  200 , without combusting the substrate. 
     The aerosol-generating article  100  comprises a housing  110  in which an aerosol-forming substrate  300  is contained. The housing  110  may be, for example, a wrapper such as a plug wrap or cigarette paper. The aerosol-generating article  100  may include a filter  140 , such as a cellulose acetate tow or other suitable filter, at the mouth end  102  downstream of the aerosol-forming substrate  300 . The end  104  of the article  100  opposite the mouth end  102  may contact the closed end of the receptacle  220  when the article  100  is inserted in the receptacle  220  of the device  200 . 
     A user may insert the mouth end  102  of the article  100  in his or her mouth and draw on the article  100 , which causes air to flow through the article  100 . The aerosol-forming substrate  300  is heated by the heating element  230  of the device  200 . As the user draws on the mouth end  102  of the article  100 , air passes through the heated substrate  300  and aerosol generated from the substrate is entrained in the air being drawn through the article  100 . The aerosol entrained in the air being drawn through the article  100  is delivered through the mouth end  102  of the article  100  for delivery to the user by inhalation. 
       FIGS.  2 A-C  illustrate a system that includes an aerosol-generating device  200  and associated aerosol-generating article  100  in accordance another embodiment of the present invention. The device  200  includes a first part  10 , a vaporizing unit  20 , and a cover  40 . In this embodiment, the aerosol-generating article  100  is in the form of a capsule comprising a housing  310  defining a reservoir in which a liquid aerosol-forming substrate  300  may be stored. 
     The first part  10  is releasably connectable to the vaporizing unit  20 . The vaporizing unit  20  is releasably connectable to the aerosol-generating article  100 . The cover  40  is disposable over the vaporizing unit  20  and aerosol-generating article (capsule)  100 . The cover  40  is releasable securable in a position relative to the vaporizing unit  20  and the aerosol-generating article  100 . In some examples (not depicted) the components of the vaporizing unit may be included in the aerosol-generating article  100 , and the system does not include a separate vaporizing unit. 
     The first part  10  comprises housing  130  defining an interior in which a power supply  240  and control electronics  250  are disposed. The control electronics  250  are electrically coupled to the power supply  240 . Electrical conductors  140  from the control electronics  250  may connect to contacts (not shown) that are exposed through, positioned on, or formed by the housing  130 . 
     The vaporizing unit  20  comprises a housing  245  in which a liquid transfer element  215  and a heating element  225  are disposed. The liquid transfer element  215  is in thermal connection with the heating element  225 . Electrical conductors  235  electrically couple the heating element  225  to electrical contacts (not shown) exposed through, or positioned on, or formed by the housing  245 . When the vaporizing unit  20  is connected to the first part  10  (for example, as shown in  FIG.  2 B ), the heating element  225  is electrically coupled with the control electronics  250  and power supply  240  via the electrical conductors  235  of the vaporizing unit  20 , the electrical conductors  140  of the first part  10  and an electrical connection between the contacts (not shown) of the first part  10  and the vaporizing unit  20 . 
     The aerosol-generating article  100  can be connected to the vaporizing unit  20 , for example, by a snap-fit, interference-fit, or any other suitable connection. When the aerosol-generating article  100  is connected to the vaporizing unit  20 , the reservoir and thus the aerosol-forming substrate  300  can be either immediately placed, or subsequently engaged, in fluid communication with the liquid transfer element  215 . For example, in this embodiment, the aerosol-generating article  100  includes valves  399  configured to be closed when the vaporizing unit and the capsule are not connected and configured to be open when the vaporizing unit and the capsule are connected. The valves  399  are aligned with distal openings in the aerosol-generating article  100  and proximal openings (not shown) in the vaporizing unit  20  such that when the valves  399  are open, liquid aerosol-forming substrate  300  in the reservoir is in communication with liquid transfer element  215 . 
     Also shown in  FIG.  2 A  is a passageway for air or aerosol flow. The vaporizing unit  20  comprises one or more inlets  244  (two shown) in housing  245  in communication with passageway  218  that extends to the proximal end of the vaporizing unit. A central passageway  315  extends through the aerosol-generating article  100  and is in communication with the passageway  218  of the vaporizing unit  20  when the vaporizing unit  20  and the aerosol-generating article  100  are connected. The cover  40  comprises a central passageway  415 . The central passageway  415  of the cover  40  is in communication with the central passageway  315  of the aerosol-generating article  100  when the cover  40  is disposed over the article  100 . 
     The cover  40  comprises a housing  410  defining a recess  416  configured to be disposed over the vaporizing unit  20  and the article  100 . The cover  40  may be maintained in position in any suitable manner, such as such as threaded engagement, snap-fit engagement, interference-fit engagement, magnetic engagement, or the like to any one or more of the first part  10 , vaporizing unit  20 , or article  100  (engagement not shown). 
       FIGS.  2 B-C  show a schematic perspective view of the aerosol-generating device  200  and associated aerosol-generating article  100  depicted in  FIG.  2 A . The device  200  shown in  FIGS.  2 B-C  includes a first part  10 , a vaporizing unit  20 , and a cover  40 . The parts are generally as described regarding  FIG.  2 A . In some examples (not depicted) the components of the vaporizing unit may be included in the aerosol-generating article, and the system would not include a separate vaporizing unit. 
     The connected system extends from a mouth end  102  to a distal end  103 . The housing of the aerosol-generating article  100  defines an opening  35  in communication with a passage through the length of the article  100 . The passage defines a portion of an aerosol flow path through the system. The housing of the vaporizing unit  20  defines an air inlet  244  in communication with a passage through the vaporizing unit  20 . The passage through the vaporizing unit  20  is in communication with the passage through the aerosol-generating article  100 . The cover  40 , which is configured to cover the vaporizing unit  20  and the aerosol-generating article  100 , comprises a housing  410  having a sidewall defining an air inlet  44  that is in communication with the air inlet  244  of the vaporizing unit  20  when the cover  40  is secured in place relative to the other parts of the system. The housing  410  of the cover  40  also defines a mouth end opening  45  that is in communication with the passage through the aerosol-generating article  100 . Accordingly, when a user draws on the mouth end  102 , air enters inlet  44  of cover  40 , then enters inlet  244  of the vaporizing unit  20 , flows through the passage in the vaporizing unit  20 , through the passage in the aerosol-generating article  100 , through the opening  35  at the proximal end of the article  100 , and through the mouth end opening  45 . 
     The first part  10  of the aerosol generating system depicted in  FIGS.  2 B-C  includes a button  15  that may be depressed to activate, and optionally, to deactivate the system. The button  15  is coupled to a switch of the control electronics. 
     Also shown in the system depicted in  FIG.  2 B , the housing  130  of the first part  10  defines a rim  12  at the proximal end. The distal end of the cover  40  abuts the rim  12  when the cover  40  is secured in place over the vaporizing unit  20  and the article  100 . The housing  410  of the cover  40  and the housing  130  of the first part  10  together form the housing of the aerosol-generating device  200 . 
     The devices  200  depicted in  FIGS.  1  and  2 A -C are merely examples of aerosol-generating devices that may be employed in accordance with the teachings presented herein. The teachings presented herein are also applicable to any other suitable aerosol-generating device, including devices configured to be used with aerosol-generating articles that include powder or gel substrates. 
     Referring now to  FIGS.  3 A-B  and  4 A-B, exemplary non-specific aerosol-generating devices  200  are depicted in schematic form. The devices  200  includes a housing  210  defining a receptacle  220  configured to receive an aerosol-generating article comprising an aerosol-forming substrate. The housing  210  also defines an interior in which control electronics  250  and a power supply  240  are disposed. The device  200  also includes a sensor  260  and shape-changing element  270  configured to change shape when activated by the control electronics  250 . The shape-changing element  270  is arranged to change the shape of the device. The control electronics  250  are operably coupled to the power supply  240 , the sensor  260 , and the shape-changing element  270 . The sensor  260  is configured to detect a state of the device  200  or an aerosol-generating article associated with the device  200 ; e.g., when the article is disposed in the receptacle  220 . The control electronics  250  are configured to permit power from the power supply  240  to be supplied to the shape-changing element  270  to activate the shape-changing element  270  when a predetermined state is detected by the sensor  260 . Activation of the shape-changing element  270  causes an exterior shape of the device  200  to change. Compare, for example,  FIG.  3 B , in which the shape-changing element  270  is activated to  FIG.  3 A , in which the shape-changing element  270  is not activated. Similarly, for example, compare  FIG.  4 B , in which the shape-changing element  270  is activated to  FIG.  4 A , in which the shape-changing element  270  is not activated. In the depicted embodiments, activation (such as application of an electrical current a voltage differential) of the shape-changing element  270 , or a portion thereof, causes an increase in the volume of the shape-changing element  270 , or a portion thereof, which causes a change in shape of the device  200 . The shape-changing element  270  of the device of  FIGS.  3 A and  3 B  is arranged to deform the housing  210  around the entire circumference the device  200 , along a portion of the length of the device  200 , to change the exterior shape of the device  200 . The shape-changing element  270  of the device of  FIGS.  4 A and  4 B  is arranged at one particular side of the device  200  to change the exterior shape of the device at that particular side when the shape-changing element is activated. 
     The device  200  may include more than one sensor  260  positioned and configured to detect a state of the device. For example, a sensor  260  may be operably coupled to the power supply  240  to measure a charge level of the power supply. A sensor  260  may be operably couplable to an aerosol-generating article when the article is inserted into the receptacle  220  of the device. A sensor  260  may be positioned and configured to detect amount or concentration of aerosol or particles flowing through a mouth end of the device  200 . 
       FIGS.  5 A- 5 B  illustrate another non-specific aerosol-generating device  200 . Like the devices depicted in  FIGS.  3 A-B  and  4 A-B, the device  200  depicted in  FIGS.  5 A-B  includes a housing  210  defining a receptacle  220  configured to receive an aerosol-generating article comprising an aerosol-forming substrate. The housing  210  also defines an interior in which control electronics  250  and a power supply  240  are disposed. The device  200  also includes a sensor  260  configured to detect a state of the device  200  or an article associated with the device  200 , such as when the article is received in the receptacle  220 . 
     The device  200  depicted in  FIGS.  5 A-B  includes a plurality of shape-changing elements  270  that configured to change the shape of the device  200  when activated. The control electronics  250  are operably coupled to the power supply  240 , the sensor  260 , and each of the shape-changing elements  270 . In this embodiment, the control electronics  250  are coupled to the shape-changing elements  270  through a multiplexor  280 . 
     The control electronics  250  are configured to permit power from the power supply  240  to activate one or more of the plurality of shape-changing element  270  when a predetermined state is detected by the sensor  260 . Activation of the shape-changing elements  270  causes an exterior shape of the device  200  to change. Compare, for example,  FIG.  5 B  in which some of the shape-changing elements  270  are activated to  FIG.  5 A  in which none of the shape-changing elements  270  are not activated. 
     As shown in  FIG.  5 B , each shape-changing element  270  may be independently controlled by the control electronics  250 . The shape-changing elements  270  may be the same or different. In some cases, such as shape-changing elements employing two-way shape memory alloys, activation of the shape-changing element may result in a full activation. In other cases, the amount of activation (e.g., application of heat) may result in partial activation of the shape-changing element. For example, application of less than full heating to a foam comprising gas bubbles may result in less than full (e.g., partial) activation of the element such that the element effects a change in shape of the device  200  to an extent less that the full change in shape that may be possible at maximum activation, as determined by, for example, instructions programmed in the control electronics  250 . 
       FIGS.  6 A-B  illustrate an embodiment of a portion of the housing  210  of an aerosol-generating device. The housing  210  includes a structural base layer  212  and an exterior layer  214  sufficiently flexible to accommodate a change in shape of a shape-changing element  270 , which is positioned between the base layer  212  and the exterior layer  214 . The depicted shape-changing element  270  includes a heating element  272  such as a resistive wire mesh, which may be operably coupled to the control electronics and power supply through appropriate electrical connections (not shown). The shape-changing element  270  also includes a thermally-responsive shape-changing material  274  disposed on the heating element  272  and includes a movable part  276  disposed on the shape-changing material  274 . Application of a current to the heating element  272  causes the temperature of the heating element  272  to increase, increasing the temperature of the shape-changing material  274 , which causes a change in shape of the shape-changing material  274 , which results in movement of the movable part  276 . In the depicted embodiment, the shape-changing material  274  increases in volume when activated, which causes the movable part  276  to move beyond an original exterior edge of the exterior layer  214  of the housing, creating a bulge  216  or distinctive feature on the exterior surface that may be detected by touch or visually, as shown in  FIG.  6 B . 
       FIGS.  7 A and  7 B  illustrate schematic top plan views of an embodiment of the portion of the housing  210  depicted in  FIGS.  6 A and  6 B , respectively. As shown in  FIG.  7 A , the surface of the housing  210  has no distinctive external features when the shape-changing element is not activated. However, when the shape-changing element is activated, the external surface of the housing  210  changes shape to reveal a feature  216  having attributes of the shape-changing element, such as the shape of the movable part. 
     While the embodiment depicted in  FIGS.  6 A-B  include a movable part  276 , a change in shape of the device may be accomplished by a shape-changing element  270  without a moveable part  276 . For example, the change in shape of the shape-changing material  274  itself may be sufficient to change the shape of the housing  210 . However, the use of a movable part  276  may allow for more consistent changes in the shape of the device and may provide for more complex changes, such as the appearance of words, letters, or symbols. That is, a top surface of the shape-changing element may provide the words, letters, or symbols, and changes in shape of the shape-changing element may allow the words, letters, or symbols to appear or disappear, depending on the state of the device. 
     In some embodiments comprising a plurality of shape changing elements  270 , each of the shape-changing elements  270  may comprise an end or a movable part that is shaped in the form of a letter or a number and that changes the exterior shape of the device  200  when the shape-changing element is activated. In these embodiments, activation of different ones of the shape-changing elements  270  may cause different words or numbers to be formed in an exterior face of the device. In other words, a word or a number may be raised or lowered in the surface of the device  200  by the activated shape-changing elements  270 . Such words or numbers may be used to convey information to a user, such as the level of charge of the power supply, whether an aerosol-generating article is received in the receptacle  220  or the type or brand of aerosol-generating article received in the receptacle  220 . 
     Referring now to  FIGS.  8 A-B  and  9 , exemplary non-specific aerosol-generating systems including aerosol-generating devices  200  and articles  100  are depicted in schematic form. The devices  200  includes a housing  210  defining a receptacle  220  configured to receive an aerosol-generating article  100  comprising an aerosol-forming substrate. The device housing  210  also defines an interior in which control electronics  250  and a power supply  240  are disposed. The device  200  also includes a sensor  260  configured to detect a state of the device  200  or the article  100 . 
     The aerosol-generating article  100  includes a housing  110  and a shape-changing element  170 . The shape changing element  170  is configured to electrically couple with the control electronics  250  of the device  200  when the article  100  is inserted into the receptacle  220 . For example, the article  100  may include one or more electrical contacts (not shown) exposed through the article housing  110  that may couple with one or more electrical contacts (not shown) exposed through an internal surface of the receptacle  220  when the article  100  is received by the receptacle  220 . The contacts (not shown) of the article  100  may be electrically coupled to the shape changing element  170 . The shape changing element  170  of the article  100  is configured to change shape when activated by the control electronics  250 . The shape-changing element  270  is arranged to change the shape of the article  100 . 
     The control electronics  250  are operably coupled to the power supply  240 , the sensor  260 , and the shape-changing element  170 . The sensor  260  is configured to detect a state of the device  200  or the aerosol-generating article  100 , when the article  100  is disposed in the receptacle  220 . The control electronics  250  are configured to permit power from the power supply  240  to be supplied to the shape-changing element  170  to activate the shape-changing element  170  when a predetermined state is detected by the sensor  260 . Activation of the shape-changing element  170  causes an exterior shape of the article  100  to change. Compare, for example,  FIG.  9 B , in which the shape-changing element  170  is activated to  FIG.  8 A , in which the shape-changing element  170  is not activated. In the depicted embodiment, activation (such as application of an electrical current a voltage differential) of the shape-changing element  170 , or a portion thereof, causes an increase in the volume of the shape-changing element  170 , or a portion thereof, which causes a change in shape of the article  100 . The shape-changing element  170  of the article  100  of  FIGS.  8 A and  8 B  is arranged to deform the housing  110  around the entire circumference the article  100 , along a portion of the length of the article  100 , and to change the exterior shape of the article  100 . 
     The device  200  may include more than one sensor  260  positioned and configured to detect a state of the device  200  or article  100 . For example, a sensor  260  may be operably coupled to the article  100  to monitor the amount of aerosol-forming substrate remaining in the article or the number of puffs taken on the article  100 . 
     All scientific and technical terms used herein have meanings commonly used in the art unless otherwise specified. The definitions provided herein are to facilitate understanding of certain terms used frequently herein. 
     As used in this specification and the appended claims, the singular forms “a”, “an”, and “the” encompass embodiments having plural referents, unless the content clearly dictates otherwise. 
     As used in this specification and the appended claims, the term “or” is generally employed in its sense including “and/or” unless the content clearly dictates otherwise. 
     As used herein, “have”, “having”, “include”, “including”, “comprise”, “comprising” or the like are used in their open-ended sense, and generally mean “including, but not limited to”. It will be understood that “consisting essentially of”, “consisting of”, and the like are subsumed in “comprising,” and the like. 
     The words “preferred” and “preferably” refer to embodiments of the invention that may afford certain benefits under certain circumstances. However, other embodiments may also be preferred under the same or other circumstances. Furthermore, the recitation of one or more preferred embodiments does not imply that other embodiments are not useful, and is not intended to exclude other embodiments from the scope of the disclosure, including the claims. 
     Any direction referred to herein, such as “top,” “bottom,” “left,” “right,” “upper,” “lower,” and other directions or orientations are described herein for clarity and brevity are not intended to be limiting of an actual device or system. Devices and systems described herein may be used in a number of directions and orientations. 
     The embodiments exemplified above are not limiting. Other embodiments consistent with the embodiments described above will be apparent to those skilled in the art.