Patent Publication Number: US-2023146798-A1

Title: Aerosol provision system

Description:
FIELD 
     The present disclosure relates to aerosol provision systems such as, but not limited to, nicotine delivery systems (e.g. electronic cigarettes and the like). 
     BACKGROUND 
     Electronic aerosol provision systems often employ an electronic cigarette (e-cigarette) or more generally an aerosol provision device. Such an aerosol provision system typically contains aerosolizable material (also called aerosol-generating material), such as a reservoir of fluid or liquid containing a formulation, typically but not necessarily including nicotine, or a solid material such as a tobacco-based product, from which a vapor/aerosol is generated for inhalation by a user, for example through heat vaporization. Thus, an aerosol provision system will typically comprise a vaporizer (also called an aerosol generator), e.g. a heating element, arranged to aerosolize a portion of aerosolizable material to generate a vapor. 
     Once a vapor has been generated, the vapor may be passed through flavoring material to add flavor to the vapor (if the aerosolizable material was not itself flavored), after which the (flavored) vapor may be then delivered to a user via a mouthpiece from the aerosol provision system. A potential drawback of existing aerosol provision systems and associated aerosol provision devices is that, and particularly for those with a visual impairment, and/or in conditions where visibility is reduced, it may not always be readily discernible as to whether the aerosol provision system is working correctly through visual means. It may not also be readily discernible in these conditions for the user to determine a current status of the aerosol provision system through visual means. 
     Various approaches are therefore described herein which seek to help address or mitigate some of these issues, through the implementation of an aerosol provision system which can be used alongside an audio output device (such as a loudspeaker, headphones, and/or a hearing aid), and in a way such that the aerosol provision system can selectively control the audio output device for providing acoustic feedback to a user of the aerosol provision system, via the audio output device, wherein the acoustic feedback relates to a predetermined condition/operation/status of the aerosol provision system. 
     The above disclosures thus also provide for mechanisms for those with a hearing impairment to more easily understand a current status of an aerosol provision system, through there being provided an aerosol provision system which can communicate with, and control the operation of, a hearing aid of a user of the aerosol provision system. 
     SUMMARY 
     According to a first aspect of certain embodiments there is provided a method of transmitting a feedback signal from an aerosol provision system to a hearing aid, the method comprising outputting acoustic feedback by a hearing aid in response to receiving the feedback signal transmitted by the aerosol provision system, and controlling the hearing aid using the feedback signal. 
     According to a second aspect of certain embodiments there is provided a method of communicating with a hearing aid, wherein the method comprises: receiving a signal transmitted by an aerosol provision system for generating an aerosol, wherein the signal is configured for controlling the hearing aid. 
     According to a third aspect of certain embodiments there is provided a feedback provision system comprising: an aerosol provision system for generating an aerosol; and a hearing aid for outputting acoustic feedback to a user of the aerosol provision system; wherein the hearing aid is configured to output the acoustic feedback in response to receiving a signal which is initially wirelessly transmitted by the aerosol provision system, wherein the signal is configured for controlling the hearing aid. 
     According to a fourth aspect of certain embodiments there is provided an aerosol provision system for generating an aerosol, wherein the aerosol provision system is configured to wirelessly transmit a signal to a hearing aid; wherein the signal is configured for controlling the hearing aid. 
     It will be appreciated that features and aspects of the disclosure described above in relation to the various aspects of the disclosure are equally applicable to, and may be combined with, embodiments of the disclosure according to other aspects of the disclosure as appropriate, and not just in the specific combinations described herein. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Embodiments of the disclosure will now be described, by way of example only, with reference to the accompanying drawings, in which: 
         FIG.  1    schematically represents in perspective view an aerosol provision system comprising a cartridge and aerosol provision device (shown separated) in accordance with certain embodiments of the disclosure. 
         FIG.  2    schematically represents in exploded perspective view of components of the cartridge of the aerosol provision system of  FIG.  1   . 
         FIGS.  3 A to  3 C  schematically represent various cross-section views of a housing part of the cartridge of the aerosol provision system of  FIG.  1   . 
         FIGS.  4 A and  4 B  schematically represent a perspective view and a plan view of a dividing wall element of the cartridge of the aerosol provision system of  FIG.  1   . 
         FIGS.  5 A to  5 C  schematically represent two perspective views and a plan view of a resilient plug of the cartridge of the aerosol provision system of  FIG.  1   . 
         FIGS.  6 A and  6 B  schematically represent a perspective view and a plan view of a bottom cap of the cartridge of the aerosol provision system of  FIG.  1   . 
         FIG.  7    schematically represents embodiments of feedback provision system, useable with an aerosol provision system such as that shown in  FIGS.  1 - 6 B , and comprising an audio output device which is configured to output acoustic feedback in response to receiving a signal which is initially transmitted by the aerosol provision system, in accordance with certain embodiments of the disclosure. 
         FIG.  8 A  schematically represents an embodiment of feedback provision system, in accordance with certain embodiments of the disclosure, where the audio output device comprises a headphone or hearing aid. 
         FIG.  8 B  schematically represents an embodiment of feedback provision system, in accordance with certain embodiments of the disclosure, where the audio output device comprises a loudspeaker which is remotely located from the aerosol provision system (namely on a table). 
         FIG.  9    schematically represents embodiments of feedback provision system, useable with an aerosol provision system such as that shown in  FIGS.  1 - 6 B , and comprising an audio output device which is configured to output acoustic feedback in response to receiving a signal which is initially transmitted by the aerosol provision system, in accordance with certain embodiments of the disclosure, wherein the aerosol provision system is configured to transmit the signal to the audio output device via an intermediary device. 
     
    
    
     DETAILED DESCRIPTION 
     Aspects and features of certain examples and embodiments are discussed/described herein. Some aspects and features of certain examples and embodiments may be implemented conventionally and these are not discussed/described in detail in the interests of brevity. It will thus be appreciated that aspects and features of apparatus and methods discussed herein which are not described in detail may be implemented in accordance with any conventional techniques for implementing such aspects and features. 
     The present disclosure relates to non-combustible aerosol provision systems (such as an e-cigarette). According to the present disclosure, a “non-combustible” aerosol provision system is one where a constituent aerosolizable material of the aerosol provision system (or component thereof) is not combusted or burned in order to facilitate delivery to a user. Aerosolizable material, which also may be referred to herein as aerosol generating material or aerosol precursor material, is material that is capable of generating aerosol, for example when heated, irradiated or energized in any other way. The aerosolizable material may also be flavored, in some embodiments. 
     Throughout the following description the term “e-cigarette” or “electronic cigarette” may sometimes be used, but it will be appreciated this term may be used interchangeably with an aerosol provision system. An electronic cigarette may also known as a vaping device or electronic nicotine delivery system (END), although it is noted that the presence of nicotine in the aerosolizable material is not a requirement. 
     In some embodiments, the aerosol provision system is a hybrid device configured to generate aerosol using a combination of aerosolizable materials, one or a plurality of which may be heated. In some embodiments, the hybrid device comprises a liquid or gel aerosolizable material and a solid aerosolizable material. The solid aerosolizable material may comprise, for example, tobacco or a non-tobacco product. 
     Typically, the (non-combustible) aerosol provision system may comprise a cartridge/consumable part and a body/reusable/aerosol provision device part, which is configured to releasably engage with the cartridge/consumable part. 
     The aerosol provision system may be provided with a means for powering a vaporizer therein, and there may be provided an aerosolizable material transport element for receiving the aerosolizable material that is to be vaporized. The aerosol provision system may also be provided with a reservoir for containing aerosolizable material, and in some embodiments a further reservoir for containing flavoring material for flavoring a generated vapor from the aerosol provision system. 
     In some embodiments, the vaporizer may be a heater/heating element capable of interacting with the aerosolizable material so as to release one or more volatiles from the aerosolizable material to form a vapor/aerosol. In some embodiments, the vaporizer is capable of generating an aerosol from the aerosolizable material without heating. For example, the vaporizer may be capable of generating a vapor/aerosol from the aerosolizable material without applying heat thereto, for example via one or more of vibrational, mechanical, pressurization or electrostatic means. 
     In some embodiments, the substance to be delivered may be an aerosolizable material which may comprise an active constituent, a carrier constituent and optionally one or more other functional constituents. 
     The active constituent may comprise one or more physiologically and/or olfactory active constituents which are included in the aerosolizable material in order to achieve a physiological and/or olfactory response in the user. The active constituent may for example be selected from nutraceuticals, nootropics, and psychoactives. The active constituent may be naturally occurring or synthetically obtained. The active constituent may comprise for example nicotine, caffeine, taurine, theine, a vitamin such as B6 or B12 or C, melatonin, a cannabinoid, or a constituent, derivative, or combinations thereof. The active constituent may comprise a constituent, derivative or extract of tobacco or of another botanical. In some embodiments, the active constituent is a physiologically active constituent and may be selected from nicotine, nicotine salts (e.g. nicotine ditartrate/nicotine bitartrate), nicotine-free tobacco substitutes, other alkaloids such as caffeine, or mixtures thereof. 
     In some embodiments, the active constituent is an olfactory active constituent and may be selected from a “flavor” and/or “flavorant” which, where local regulations permit, may be used to create a desired taste, aroma or other somatosensorial sensation in a product for adult consumers. In some instances such constituents may be referred to as flavors, flavorants, flavoring material, cooling agents, heating agents, and/or sweetening agents. They may include naturally occurring flavor materials, botanicals, extracts of botanicals, synthetically obtained materials, or combinations thereof (e.g., tobacco, cannabis, licorice (liquorice), hydrangea, eugenol, Japanese white bark magnolia leaf, chamomile, fenugreek, clove, maple, matcha, menthol, Japanese mint, aniseed (anise), cinnamon, turmeric, Indian spices, Asian spices, herb, wintergreen, cherry, berry, red berry, cranberry, peach, apple, orange, mango, clementine, lemon, lime, tropical fruit, papaya, rhubarb, grape, durian, dragon fruit, cucumber, blueberry, mulberry, citrus fruits, Drambuie, bourbon, scotch, whiskey, gin, tequila, rum, spearmint, peppermint, lavender, aloe vera, cardamom, celery, cascarilla, nutmeg, sandalwood, bergamot, geranium, khat, naswar, betel, shisha, pine, honey essence, rose oil, vanilla, lemon oil, orange oil, orange blossom, cherry blossom, cassia, caraway, cognac, jasmine, ylang-ylang, sage, fennel, wasabi, piment, ginger, coriander, coffee, hemp, a mint oil from any species of the genus Mentha, eucalyptus, star anise, cocoa, lemongrass, rooibos, flax,  Ginkgo biloba , hazel, hibiscus, laurel, mate, orange skin, rose, tea such as green tea or black tea, thyme, juniper, elderflower, basil, bay leaves, cumin, oregano, paprika, rosemary, saffron, lemon peel, mint, beefsteak plant, curcuma, cilantro, myrtle, cassis, valerian, pimento, mace, damien, marjoram, olive, lemon balm, lemon basil, chive, carvi, verbena, tarragon, limonene, thymol, camphene), flavor enhancers, bitterness receptor site blockers, sensorial receptor site activators or stimulators, sugars and/or sugar substitutes (e.g., sucralose, acesulfame potassium, aspartame, saccharine, cyclamates, lactose, sucrose, glucose, fructose, sorbitol, or mannitol), and other additives such as charcoal, chlorophyll, minerals, botanicals, or breath freshening agents. They may be imitation, synthetic or natural ingredients or blends thereof. They may be in any suitable form, for example, liquid such as an oil, solid such as a powder, or gasone or more of extracts (e.g., licorice, hydrangea, Japanese white bark magnolia leaf, chamomile, fenugreek, clove, menthol, Japanese mint, aniseed, cinnamon, herb, wintergreen, cherry, berry, peach, apple, Drambuie, bourbon, scotch, whiskey, spearmint, peppermint, lavender, cardamom, celery, cascarilla, nutmeg, sandalwood, bergamot, geranium, honey essence, rose oil, vanilla, lemon oil, orange oil, cassia, caraway, cognac, jasmine, ylang-ylang, sage, fennel, piment, ginger, anise, coriander, coffee, or a mint oil from any species of the genus Mentha), flavor enhancers, bitterness receptor site blockers, sensorial receptor site activators or stimulators, sugars and/or sugar substitutes (e.g., sucralose, acesulfame potassium, aspartame, saccharine, cyclamates, lactose, sucrose, glucose, fructose, sorbitol, or mannitol), and other additives such as charcoal, chlorophyll, minerals, botanicals, or breath freshening agents. They may be imitation, synthetic or natural ingredients or blends thereof. They may be in any suitable form, for example, oil, liquid, or powder. 
     In some embodiments, the flavoring material (flavor) may comprise menthol, spearmint and/or peppermint. In some embodiments, the flavor comprises flavor components of cucumber, blueberry, citrus fruits and/or redberry. In some embodiments, the flavor comprises eugenol. In some embodiments, the flavor comprises flavor components extracted from tobacco. In some embodiments, the flavor may comprise a sensate, which is intended to achieve a somatosensorial sensation which are usually chemically induced and perceived by the stimulation of the fifth cranial nerve (trigeminal nerve), in addition to or in place of aroma or taste nerves, and these may include agents providing heating, cooling, tingling, numbing effect. A suitable heat effect agent may be, but is not limited to, vanillyl ethyl ether and a suitable cooling agent may be, but not limited to eucalyptol, WS-3. 
     The carrier constituent may comprise one or more constituents capable of forming an aerosol. In some embodiments, the carrier constituent may comprise one or more of glycerine, glycerol, propylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, 1,3-butylene glycol, erythritol, meso-Erythritol, ethyl vanillate, ethyl laurate, a diethyl suberate, triethyl citrate, triacetin, a diacetin mixture, benzyl benzoate, benzyl phenyl acetate, tributyrin, lauryl acetate, lauric acid, myristic acid, and propylene carbonate. 
     The one or more other functional constituents may comprise one or more of pH regulators, coloring agents, preservatives, binders, fillers, stabilizers, and/or antioxidants. 
     As noted above, aerosol provision systems (e-cigarettes) may often comprise a modular assembly including both a reusable part (body—or aerosol provision device) and a replaceable consumable (cartridge) part. Devices conforming to this type of two-part modular configuration may generally be referred to as two-part devices. It is also common for electronic cigarettes to have a generally elongate shape. For the sake of providing a concrete example, certain embodiments of the disclosure described herein may comprise this kind of generally elongate two-part device employing consumable parts. However, it will be appreciated the underlying principles described herein may equally be adopted for other electronic cigarette configurations, for example modular devices comprising more than two parts, as devices conforming to other overall shapes, for example based on so-called box-mod high performance devices that typically have a more boxy shape. 
     From the forgoing therefore, and with reference to  FIG.  1    is a schematic perspective view of an example aerosol provision system (e-cigarette)  1  in accordance with certain embodiments of the disclosure. Terms concerning the relative location of various aspects of the electronic cigarette (e.g. terms such as upper, lower, above, below, top, bottom etc.) are used herein with reference to the orientation of the electronic cigarette as shown in  FIG.  1    (unless the context indicates otherwise). However, it will be appreciated this is purely for ease of explanation and is not intended to indicate there is any required orientation for the electronic cigarette in use. 
     The e-cigarette  1  (aerosol provision system  1 ) comprises two main components, namely a cartridge  2  and an aerosol provision device  4 . The aerosol provision device  4  and the cartridge  2  are shown separated in  FIG.  1   , but are coupled together when in use. 
     The cartridge  2  and aerosol provision device  4  are coupled by establishing a mechanical and electrical connection between them. The specific manner in which the mechanical and electrical connection is established is not of primary significance to the principles described herein and may be established in accordance with conventional techniques, for example based around a screw thread, bayonet, latched or friction-fit mechanical fixing with appropriately arranged electrical contacts/electrodes for establishing the electrical connection between the two parts as appropriate. For example electronic cigarette  1  represented in  FIG.  1   , the cartridge comprises a mouthpiece  33 , a mouthpiece end  52  and an interface end  54  and is coupled to the aerosol provision device by inserting an interface end portion  6  at the interface end of the cartridge into a corresponding receptacle  8 /receiving section of the aerosol provision device. The interface end portion  6  of the cartridge is a close fit to be receptacle  8  and includes protrusions  56  which engage with corresponding detents in the interior surface of a receptacle wall  12  defining the receptacle  8  to provide a releasable mechanical engagement between the cartridge and the aerosol provision device. An electrical connection is established between the aerosol provision device and the cartridge via a pair of electrical contacts on the bottom of the cartridge (not shown in  FIG.  1   ) and corresponding sprung contact pins in the base of the receptacle  8  (not shown in  FIG.  1   ). As noted above, the specific manner in which the electrical connection is established is not significant to the principles described herein, and indeed some implementations might not have an electrical connection between the cartridge and a aerosol provision device at all, for example because the transfer of electrical power from the reusable part to the cartridge may be wireless (e.g. based on electromagnetic induction techniques). 
     The electronic cigarette  1  (aerosol provision system) has a generally elongate shape extending along a longitudinal axis L. When the cartridge is coupled to the aerosol provision device, the overall length of the electronic cigarette in this example (along the longitudinal axis) is around 12.5 cm. The overall length of the aerosol provision device is around 9 cm and the overall length of the cartridge is around 5 cm (i.e. there is around 1.5 cm of overlap between the interface end portion  6  of the cartridge and the receptacle  8  of the aerosol provision device when they are coupled together). The electronic cigarette has a cross-section which is generally oval and which is largest around the middle of the electronic cigarette and tapers in a curved manner towards the ends. The cross-section around the middle of the electronic cigarette has a width of around 2.5 cm and a thickness of around 1.7 cm. The end of the cartridge has a width of around 2 cm and a thickness of around 0.6 mm, whereas the other end of the electronic cigarette has a width of around 2 cm and a thickness of around 1.2 cm. The outer housing of the electronic cigarette is in this example is formed from plastic. It will be appreciated the specific size and shape of the electronic cigarette and the material from which it is made is not of primary significance to the principles described herein and may be different in different implementations. That is to say, the principles described herein may equally be adopted for electronic cigarettes having different sizes, shapes and/or materials. 
     The aerosol provision device  4  may in accordance with certain embodiments of the disclosure be broadly conventional in terms of its functionality and general construction techniques. In the example of  FIG.  1   , the aerosol provision device  4  comprises a plastic outer housing  10  including the receptacle wall  12  that defines the receptacle  8  for receiving the end of the cartridge as noted above. The outer housing  10  of the aerosol provision device  4  in this example has a generally oval cross section conforming to the shape and size of the cartridge  2  at their interface to provide a smooth transition between the two parts. The receptacle  8  and the end portion  6  of the cartridge  2  are symmetric when rotated through 180° so the cartridge can be inserted into the aerosol provision device in two different orientations. The receptacle wall  12  includes two aerosol provision device air inlet openings  14  (i.e. holes in the wall). These openings  14  are positioned to align with an air inlet  50  for the cartridge when the cartridge is coupled to the aerosol provision device. A different one of the openings  14  aligns with the air inlet  50  of the cartridge in the different orientations. It will be appreciated some implementations may not have any degree of rotational symmetry such that the cartridge is coupleable to the aerosol provision device in only one orientation while other implementations may have a higher degree of rotational symmetry such that the cartridge is coupleable to the aerosol provision device in more orientations. 
     The aerosol provision device further comprises a battery  16  for providing operating power for the electronic cigarette, control circuitry  18  for controlling and monitoring the operation of the electronic cigarette, a user input button  20 , an indicator light  22 , and a charging port  24 . 
     The battery  16  in this example is rechargeable and may be of a conventional type, for example of the kind normally used in electronic cigarettes and other applications requiring provision of relatively high currents over relatively short periods. The battery  16  may be recharged through the charging port  24 , which may, for example, comprise a USB connector. 
     The input button  20  in this example is a conventional mechanical button, for example comprising a sprung mounted component which may be pressed by a user to establish an electrical contact in underlying circuitry. In this regard, the input button may be considered an input device for detecting user input, e.g. to trigger aerosol generation, and the specific manner in which the button is implemented is not significant. For example, other forms of mechanical button or touch-sensitive button (e.g. based on capacitive or optical sensing techniques) may be used in other implementations, or there may be no button and the device may rely on a puff detector for triggering aerosol generation. 
     The indicator light  22  is provided to give a user with a visual indication of various characteristics associated with the electronic cigarette, for example, an indication of an operating state (e.g. on/off/standby), and other characteristics, such as battery life or fault conditions. Different characteristics may, for example, be indicated through different colors and/or different flash sequences in accordance with generally conventional techniques. 
     The control circuitry  18  is suitably configured/programmed to control the operation of the electronic cigarette to provide conventional operating functions in line with the established techniques for controlling electronic cigarettes. The control circuitry (processor circuitry)  18  may be considered to logically comprise various sub-units/circuitry elements associated with different aspects of the electronic cigarette&#39;s operation. For example, depending on the functionality provided in different implementations, the control circuitry  18  may comprises power supply control circuitry for controlling the supply of power from the battery/power supply to the cartridge in response to user input, user programming circuitry for establishing configuration settings (e.g. user-defined power settings) in response to user input, as well as other functional units/circuitry associated functionality in accordance with the principles described herein and conventional operating aspects of electronic cigarettes, such as indicator light display driving circuitry and user input detection circuitry. It will be appreciated the functionality of the control circuitry  18  can be provided in various different ways, for example using one or more suitably programmed programmable computer(s) and/or one or more suitably configured application-specific integrated circuit(s)/circuitry/chip(s)/chipset(s) configured to provide the desired functionality. 
       FIG.  2    is an exploded schematic perspective view of the cartridge  2  (exploded along the longitudinal axis L). The cartridge  2  comprises a housing part  32 , an air channel seal  34 , a dividing wall element  36 , an outlet tube  38 , a vaporizer/heating element  40 , an aerosolizable material transport element  42 , a plug  44 , and an end cap  48  with contact electrodes  46 .  FIGS.  3  to  6    schematically represents some of these components in more detail. 
       FIG.  3 A  is a schematic cut-away view of the housing part  32  through the longitudinal axis L where the housing part  32  is thinnest.  FIG.  3 B  is a schematic cut-away view of the housing part  32  through the longitudinal axis L where the housing part  32  is widest.  FIG.  3 C  is a schematic view of the housing part along the longitudinal axis L from the interface end  54  (i.e. viewed from below in the orientation of  FIGS.  3 A and  3 B ). 
       FIG.  4 A  is a schematic perspective view of the dividing wall element  36  as seen from below.  FIG.  4 B  is a schematic cross-section through an upper part of the dividing wall element  36  as viewed from below. 
       FIG.  5 A  is a schematic perspective view of the plug  44  from above and  FIG.  5 B  is a schematic perspective view of the plug  44  from below.  FIG.  5 C  is a schematic view of the plug  44  along the longitudinal axis L seen from the mouthpiece end  52  of the cartridge (i.e. viewed from above for the orientation in  FIGS.  1  and  2   ). 
       FIG.  6 A  is a schematic perspective view of the end cap  48  from above.  FIG.  6 B  is a schematic view of the end cap  48  along the longitudinal axis L seen from the mouthpiece end  52  of the cartridge (i.e. from above). 
     The housing part  32  in this example comprises a housing outer wall  64  and a housing inner tube  62  which in this example are formed from a single molding of polypropylene. The housing outer wall  64  defines the external appearance of the cartridge  2  and the housing inner tube  62  defines a part the air channel through the cartridge. The housing part is open at the interface end  54  of the cartridge and closed at the mouthpiece end  52  of the cartridge except for a mouthpiece opening/aerosol outlet  60 , from the mouthpiece  33 , which is in fluid communication with the housing inner tube  62 . The housing part  32  includes an opening in a sidewall which provides the air inlet  50  for the cartridge. The air inlet  50  in this example has an area of around 2 mm 2 . The outer surface of the outer wall  64  of the housing part  32  includes the protrusions  56  discussed above which engage with corresponding detents in the interior surface of the receptacle wall  12  defining the receptacle  8  to provide a releasable mechanical engagement between the cartridge and the aerosol provision device. The inner surface of the outer wall  64  of the housing part includes further protrusions  66  which act to provide an abutment stop for locating the dividing wall element  36  along the longitudinal axis L when the cartridge is assembled. The outer wall  64  of the housing part  32  further comprises holes which provide latch recesses  68  arranged to receive corresponding latch projections  70  in the end cap to fix the end cap to be housing part when the cartridge is assembled. 
     The outer wall  64  of the housing part  32  includes a double-walled section  74  that defines a gap  76  in fluid communication with the air inlet  50 . The gap  76  provides a portion of the air channel through the cartridge. In this example the doubled-walled section  74  of the housing part  32  is arranged so the gap defines an air channel running within the housing outer wall  64  parallel to the longitudinal axis with a cross-section in a plane perpendicular to the longitudinal axis of around 3 mm 2 . The gap/portion of air channel  76  defined by the double-walled section of the housing part extends down to the open end of the housing part  32 . 
     The air channel seal  34  is a silicone molding generally in the form of a tube having a through hole  80 . The outer wall of the air channel seal  34  includes circumferential ridges  84  and an upper collar  82 . The inner wall of the air channel seal  34  also includes circumferential ridges, but these are not visible in  FIG.  2   . When the cartridge is assembled the air channel seal  34  is mounted to the housing inner tube  62  with an end of the housing inner tube  62  extending partly into the through hole  80  of the air channel seal  34 . The through hole  80  in the air channel seal has a diameter of around 5.8 mm in its relaxed state whereas the end of the housing inner tube  62  has a diameter of around 6.2 mm so that a seal is formed when the air channel seal  34  is stretched to accommodate the housing inner tube  62 . This seal is facilitated by the ridges on the inner surface of the air channel seal  34 . 
     The outlet tube  38  comprises a tubular section, for instance made of ANSI 304 stainless steel or polypropylene, with an internal diameter of around 8.6 mm and a wall thickness of around 0.2 mm. The bottom end of the outlet tube  38  includes a pair of diametrically opposing slots  88  with an end of each slot having a semi-circular recess  90 . When the cartridge is assembled the outlet tube  38  mounts to the outer surface of the air channel seal  34 . The outer diameter of the air channel seal is around 9.0 mm in its relaxed state so that a seal is formed when the air channel seal  34  is compressed to fit inside the outlet tube  38 . This seal is facilitated by the ridges  84  on the outer surface of the air channel seal  34 . The collar  80  on the air channel seal  34  provides a stop for the outlet tube  38 . 
     The aerosolizable material transport element  42  comprises a capillary wick and the vaporizer (aerosol generator)  40  comprises a resistance wire heater wound around the capillary wick. In addition to the portion of the resistance wire wound around the capillary wick, the vaporizer comprises electrical leads  41  which pass through holes in the plug  44  to contact electrodes  46  mounted to the end cap  54  to allow power to be supplied to the vaporizer via the electrical interface the established when the cartridge is connected to an aerosol provision device. The vaporizer leads  41  may comprise the same material as the resistance wire wound around the capillary wick, or may comprise a different material (e.g. lower-resistance material) connected to the resistance wire wound around the capillary wick. In this example the heater coil  40  comprises a nickel iron alloy wire and the wick  42  comprises a glass fiber bundle. The vaporizer and aerosolizable material transport element may be provided in accordance with any conventional techniques and is may comprise different forms and/or different materials. For example, in some implementations the wick may comprise fibrous or solid a ceramic material and the heater may comprise a different alloy. In other examples the heater and wick may be combined, for example in the form of a porous and a resistive material. More generally, it will be appreciated the specific nature aerosolizable material transport element and vaporizer is not of primary significance to the principles described herein. 
     When the cartridge is assembled, the wick  42  is received in the semi-circular recesses  90  of the outlet tube  38  so that a central portion of the wick about which the heating coil is would is inside the outlet tube while end portions of the wick are outside the outlet tube  38 . 
     The plug  44  in this example comprises a single molding of silicone, may be resilient. The plug comprises a base part  100  with an outer wall  102  extending upwardly therefrom (i.e. towards the mouthpiece end of the cartridge). The plug further comprises an inner wall  104  extending upwardly from the base part  100  and surrounding a through hole  106  through the base part  100 . 
     The outer wall  102  of the plug  44  conforms to an inner surface of the housing part  32  so that when the cartridge is assembled the plug in  44  forms a seal with the housing part  32 . The inner wall  104  of the plug  44  conforms to an inner surface of the outlet tube  38  so that when the cartridge is assembled the plug  44  also forms a seal with the outlet tube  38 . The inner wall  104  includes a pair of diametrically opposing slots  108  with the end of each slot having a semi-circular recess  110 . Extended outwardly (i.e. in a direction away from the longitudinal axis of the cartridge) from the bottom of each slot in the inner wall  104  is a cradle section  112  shaped to receive a section of the aerosolizable material transport element  42  when the cartridge is assembled. The slots  108  and semi-circular recesses  110  provided by the inner wall of the plug  44  and the slots  88  and semi-circular recesses  90  of the outlet tube  38  are aligned so that the slots  88  in the outlet tube  38  accommodate respective ones of the cradles  112  with the respective semi-circular recesses in the outlet tube and plug cooperating to define holes through which the aerosolizable material transport element passes. The size of the holes provided by the semi-circular recesses through which the aerosolizable material transport element passes correspond closely to the size and shape of the aerosolizable material transport element, but are slightly smaller so a degree of compression is provided by the resilience of the plug  44 . This allows aerosolizable material to be transported along the aerosolizable material transport element by capillary action while restricting the extent to which aerosolizable material which is not transported by capillary action can pass through the openings. As noted above, the plug  44  includes further openings  114  in the base part  100  through which the contact leads  41  for the vaporizer pass when the cartridge is assembled. The bottom of the base part of the plug includes spacers  116  which maintain an offset between the remaining surface of the bottom of the base part and the end cap  48 . These spacers  116  include the openings  114  through which the electrical contact leads  41  for the vaporizer pass. 
     The end cap  48  comprises a polypropylene molding with a pair of gold-plated copper electrode posts  46  mounted therein. 
     The ends of the electrode posts  44  on the bottom side of the end cap are close to flush with the interface end  54  of the cartridge provided by the end cap  48 . These are the parts of the electrodes to which correspondingly aligned sprung contacts in the aerosol provision device  4  connect when the cartridge  2  is assembled and connected to the aerosol provision device  4 . The ends of the electrode posts on the inside of the cartridge extend away from the end cap  48  and into the holes  114  in the plug  44  through which the contact leads  41  pass. The electrode posts are slightly oversized relative to the holes  114  and include a chamfer at their upper ends to facilitate insertion into the holes  114  in the plug where they are maintained in pressed contact with the contact leads for the vaporizer by virtue of the plug. 
     The end cap has a base section  124  and an upstanding wall  120  which conforms to the inner surface of the housing part  32 . The upstanding wall  120  of the end cap  48  is inserted into the housing part  32  so the latch projections  70  engage with the latch recesses  68  in the housing part  32  to snap-fit the end cap  48  to the housing part when the cartridge is assembled. The top of the upstanding wall  120  of the end cap  48  abuts a peripheral part of the plug  44  and the lower face of the spacers  116  on the plug also abut the base section  124  of the plug so that when the end cap  48  is attached to the housing part it presses against the resilient part  44  to maintain it in slight compression. 
     The base portion  124  of the end cap  48  includes a peripheral lip  126  beyond the base of the upstanding wall  112  with a thickness which corresponds with the thickness of the outer wall of the housing part at the interface end of the cartridge. The end cap also includes an upstanding locating pin  122  which aligns with a corresponding locating hole  128  in the plug to help establish their relative location during assembly. 
     The dividing wall element  36  comprises a single molding of polypropylene and includes a dividing wall  130  and a collar  132  formed by projections from the dividing wall  130  in the direction towards the interface end of the cartridge. The dividing wall element  36  has a central opening  134  through which the outlet tube  38  passes (i.e. the dividing wall is arranged around the outlet tube  38 ). In some embodiments, the dividing wall element  36  may be integrally formed with the outlet tube  38 . When the cartridge is assembled, the upper surface of the outer wall  102  of the plug  44  engages with the lower surface of the dividing wall  130 , and the upper surface of the dividing wall  130  in turn engages with the projections  66  on the inner surface of the outer wall  64  of the housing part  32 . Thus, the dividing wall  130  prevents the plug from being pushed too far into the housing part  32 —i.e. the dividing wall  130  is fixedly located along the longitudinal axis of the cartridge by the protrusions  66  in the housing part and so provides the plug with a fixed surface to push against. The collar  132  formed by projections from the dividing wall includes a first pair of opposing projections/tongues  134  which engage with corresponding recesses on an inner surface of the outer wall  102  of the plug  44 . The protrusions from the dividing wall  130  further provide a pair of cradle sections  136  configured to engage with corresponding ones of the cradle sections  112  in the part  44  when the cartridge is assembled to further define the opening through which the aerosolizable material transport element passes. 
     When the cartridge  2  is assembled an air channel extending from the air inlet  50  to the aerosol outlet  60  through the cartridge is formed. Starting from the air inlet  50  in the side wall of the housing part  32 , a first section of the air channel is provided by the gap  76  formed by the double-walled section  74  in the outer wall  64  of the housing part  32  and extends from the air inlet  50  towards the interface end  54  of the cartridge and past the plug  44 . A second portion of the air channel is provided by the gap between the base of the plug  44  and the end cap  48 . A third portion of the air channel is provided by the hole  106  through the plug  44 . A fourth portion of the air channel is provided by the region within the inner wall  104  of the plug and the outlet tube around the vaporizer  40 . This fourth portion of the air channel may also be referred to as an aerosol/aerosol generation region, it being the primary region in which aerosol is generated during use. The air channel from the air inlet  50  to the aerosol generation region may be referred to as an air inlet section of the air channel. A fifth portion of the air channel is provided by the remainder of the outlet tube  38 . A sixth portion of the air channel is provided by the outer housing inner tube  62  which connects the air channel to the aerosol outlet  60 , which is located at an end of the mouthpiece  33 . The air channel from the aerosol generation region to be the aerosol outlet may be referred to as an aerosol outlet section of the air channel. 
     Also, when the cartridge is assembled a reservoir  31  for aerosolizable material is formed by the space outside the air channel and inside the housing part  32 . This may be filled during manufacture, for example through a filling hole which is then sealed, or by other means. The specific nature of the aerosolizable material, for example in terms of its composition, is not of primary significance to the principles described herein, and in general any conventional aerosolizable material of the type normally used in electronic cigarettes may be used. The present disclosure may refer to a liquid as the aerosolizable material, which as mentioned above may be a conventional e-liquid. However, the principles of the present disclosure apply to any aerosolizable material which has the ability to flow, and may include a liquid, a gel, or a solid, where for a solid a plurality of solid particles may be considered to have the ability to flow when considered as a bulk. 
     The reservoir is closed at the interface end of the cartridge by the plug  44 . The reservoir includes a first region above the dividing wall  130  and a second region below the dividing wall  130  within the space formed between the air channel and the outer wall of the plug. The aerosolizable material transport element (capillary wick)  42  passes through openings in the wall of the air channel provided by the semi-circular recesses  108 ,  90  in the plug  44  and the outlet tube  38  and the cradle sections  112 ,  136  in the plug  44  and the dividing wall element  36  that engage with one another as discussed above. Thus, the ends of the aerosolizable material transport element extend into the second region of the reservoir from which they draw aerosolizable material through the openings in the air channel to the vaporizer  40  for subsequent vaporization. 
     In normal use, the cartridge  2  is coupled to the aerosol provision device  4  and the aerosol provision device activated to supply power to the cartridge via the contact electrodes  46  in the end cap  48 . Power then passes through the connection leads  41  to the vaporizer  40 . The vaporizer is thus electrically heated and so vaporizes a portion of the aerosolizable material from the aerosolizable material transport element in the vicinity of the vaporizer. This generates aerosol in the aerosol generation region of the air path. Aerosolizable material that is vaporized from the aerosolizable material transport element is replaced by more aerosolizable material drawn from the reservoir by capillary action. While the vaporizer is activated, a user inhales on the mouthpiece end  52  of the cartridge. This causes air to be drawn through whichever aerosol provision device air inlet  14  aligns with the air inlet  50  of the cartridge (which will depend on the orientation in which the cartridge was inserted into the aerosol provision device receptacle  8 ). Air then enters the cartridge through the air inlet  50 , passes along the gap  76  in the double-walled section  74  of the housing part  32 , passes between the plug  44  and the end cap  48  before entering the aerosol generation region surrounding the vaporizer  40  through the hole  106  in the base part  100  of the plug  44 . The incoming air mixes with aerosol generated from the vaporizer to form a condensation aerosol, which is then drawn along the outlet tube  38  and the housing part inner  62  before exiting through the mouthpiece outlet/aerosol outlet  60  for user inhalation. 
     From the above  FIGS.  1 - 6 B , it can be seen a possible embodiment construction of aerosol provision system  1  which is configured for generating an aerosol, which is suitable for use in the context of the present disclosure (alongside potentially other forms of aerosol provision system). 
     Turning now to  FIGS.  7 - 9   , the present disclosure also provides for a feedback provision system  300  comprising an aerosol provision system  1  for generating an aerosol. The feedback system also comprises an audio output device  200  for outputting acoustic feedback to a user of the aerosol provision system. In this way, the audio output device  200  may be then configured to output the acoustic feedback in response to receiving a signal  290 , or more specifically a feedback signal, which is initially transmitted by the aerosol provision system  1 . In this way, the signal/feedback signal  290  may be configured for controlling the audio output device  200 . 
     At a general level therefore, it may be seen that the audio output device  200  is configured to be controlled by the aerosol provision system  1 , to allow the audio output device  200  to output a sound; an audible prompt; a jingle; a fixed tone; and/or some other audible cue (i.e. each of these being ‘acoustic feedback’  292  at a general level), following receipt of an appropriate signal  290  to do so from the aerosol provision system  1 . In this way, the user may then be able to detect/hear this acoustic feedback  292  (which could be a sound or some other audible prompt as noted above) for the user to then take appropriate action in response. Indeed, the acoustic feedback  292  in accordance with some embodiments may comprise feedback which is indicative of a predetermined function/operation/characteristic of the aerosol provision system  1 , and/or indicative of a predetermined event relating to the aerosol provision system as having being satisfied, and/or having being determined as being satisfied by the aerosol provision system  1 , as will be described. 
     Particularly for those individuals who might have a visual impairment, and/or for use in conditions where general visibility is otherwise low or poor, it may be appreciated that this functionality of the aerosol provision system  1  to therefore effect/control the operation of the audio output device  200  may thus allow for acoustic feedback  292  to be appropriately provided in these conditions. 
     Noting the above, and with reference to any such audio output device  200 , it is noted that in accordance with some embodiments (such as those shown in the embodiments of  FIGS.  7 - 9   ), the audio output device  200  may be remotely located from the aerosol provision system  1 . In this way, and/or put differently, in accordance with some embodiments, the aerosol provision system  1  may not comprise the audio output device  200 . 
     In this respect as well, and in so far as the audio output device  200  may be remotely located from the aerosol provision system  1 , it is envisaged in some embodiments that the aerosol provision system  1  may be configured to wirelessly transmit the signal  290  directly to the audio output device  200 , as opposed to via a wired connection between the aerosol provision system  1  and the audio output device  200 . Via the use of a wireless connection, this may therefore facilitate easier maneuverability for the user whilst they are using the aerosol provision system  1  (and its associated audio output device  200 ). Although not necessarily, in a particularly convenient embodiment, the (feedback) signal  290  from the aerosol provision system  1  may be wirelessly transmitted by the aerosol provision system  1  by Bluetooth®, or via a Wi-Fi connection in accordance with some embodiments. 
     The above being said, a wired connection may appreciably be additionally/alternatively employed in accordance with some embodiments, particularly in instances where a more reliable connection is required between the aerosol provision system  1  and its associated audio output device  200 . In this way, the aerosol provision system  1  may be configured to transmit the (feedback) signal  290  to the audio output device  200  by a wired, or physical, connection between the aerosol provision system  1  and the audio output device  200 . Or put differently, in accordance with some related embodiments, the aerosol provision system  1  may be physically connected to the audio output device  200 . 
     In accordance with some embodiments where a wired connection is employed, it may be appreciated that this may help reduce battery consumption from otherwise transmitting the signal from the aerosol provision system  1  to the audio output device  200  by a wireless connection. Where a wired connection is employed, appreciably in accordance with some narrower embodiments, the wired connection may comprise a cable connection (such as a USB connection, or Lightning® connection, in accordance with some particularly narrow embodiments) between the aerosol provision system  1  and the audio output device  200 . In a very particular embodiment, the aerosol provision system  1  may comprise an audio output port for allowing a wired connection with the audio output device  200 . Appreciably, such an audio output port could appreciably comprise a 3.5 mm or a 6.35 mm audio output port in a very particular embodiment. 
     Appreciating the foregoing, in accordance with some embodiments (such as those shown in the embodiments from  FIGS.  7 - 8 B ), the aerosol provision system  1  may be configured to transmit any signal/feedback signal  290  directly to the audio output device  200 , for instance as opposed to providing/transmitting the signal via a mobile phone or some other intermediary electronic device. In this way, the reliability and speed of transmission of the signal from the aerosol provision system  1  to the audio output device  200  may be improved. 
     Appreciably however, it is envisaged that the feedback provision system  300  herein provided may, in accordance with some embodiments (such as the embodiment from  FIG.  9   ), further comprise an intermediary device  295 , or second device  295 , for conveying the signal  290  from the aerosol provision system  1  to the audio output device  200 . Such a second or intermediary device  295 , in accordance with some embodiments, may comprise a dongle or a mobile phone, as shown in the embodiment of  FIG.  9   , for instance. Appreciably, any such intermediary device  295  may be then configured to receive the signal  290 A from the aerosol provision system  1 , and be configured to transmit the signal (see signal  290 B from  FIG.  9   ) to the audio output device  200  (for instance via a wireless transceiver  296 ), in accordance with some particularly narrow embodiments where the signal is wirelessly transmitted from the aerosol provision system  1  and/or wirelessly transmitted to the audio output device  200 . 
     Noting the above, it may be seen that the aerosol provision system  1  may transmit the signal  290  to the audio output device  200  in a number of different ways. As to the nature of this audio output device  200 , it is envisaged that this could comprise any form of electroacoustic transducer  202  which is configured to output a sound signal. This being the case therefore, and in accordance with some embodiments, the audio output device  200  may comprise at least one of a loudspeaker (as shown in the embodiment of  FIG.  8 B ); or a headphone or earphone (as shown in the embodiment of  FIG.  8 A ). In this way, the feedback provision system  300  may be particularly effective at providing feedback  292 , in the form of acoustic feedback, which can be perceived by the user in low-light conditions or in conditions where user visibility is otherwise restricted/poor. 
     Additionally/alternatively however, in accordance with some embodiments, the audio output device  200  may comprise a bone conduction audio output device; and/or even a hearing aid (as shown in the embodiment of  FIG.  8 A ). In this way, the feedback provision system  300  may be particularly effective at providing feedback  292 , in the form of acoustic feedback, which can be perceived by those who have a hearing impediment, or for those who might not otherwise be able to hear acoustic feedback delivered from an electroacoustic transducer  202  located on the aerosol provision system  1  itself. 
     With respect to any feedback signal  290  which is transmitted to the audio output device  200 , the feedback signal may in accordance with some embodiments appreciably comprise an audio output signal which is configured to be output by the audio output device as part of the acoustic feedback. In this way, the feedback signal may provide the audio output device with a signal which can be conveniently directly output with minimal subsequent processing by further intermediary electronics. 
     Staying with the signal  290 , in accordance with some particular embodiments, the feedback signal may be conveniently configured to be transmitted by the aerosol provision system  1  in response to a predetermined event being satisfied, and/or in response to a predetermined event being determined as being satisfied by the aerosol provision system. In this way, the acoustic feedback may be output by the audio output device for providing a prompt/notification that the predetermined event has occurred/been satisfied. 
     As to what such a predetermined event might be, appreciably this could comprise a number of different things, depending on the intended application of the acoustic feedback which is to be outputted. 
     For instance, in accordance with some embodiments, and at a general level, the predetermined event may comprise the aerosol provision system  1  changing from a first mode of operation to a second mode of operation. For instance, in accordance with some embodiments, either of these modes of operation may comprise a standby mode; a sleep mode; or an off status. In this way, and in accordance with some narrower or alterative embodiments, the other of these modes of operation may comprise a standby mode; a sleep mode; or an off status (which is not the same as the first mode of operation). By virtue of this functionality therefore, the acoustic feedback  292  may provide an indication that the aerosol provision system  1  has changed between these two modes of operation, which could be particularly helpful if this change of mode of operation inadvertently happens (e.g. whilst the aerosol provision system  1  is in a pocket, or bag, where the user may not otherwise be able to visually determine that the change of mode of operation has occurred). 
     Appreciably as well, noting the above disclosure, in accordance with some embodiments, the predetermined event may comprise at least one of; i) the aerosol provision system being switched on; and/or ii) the aerosol provision system being switched off. 
     Related to the above as well, in accordance with some embodiments, and particularly those where the aerosol provision system  1  comprises an aerosol generator  40 , for aerosolizing aerosol-generating material, for generating the aerosol, in accordance with some embodiments thereof, the predetermined event may comprise any combination of:
         i) the aerosol generator being operated;   ii) the aerosol generator being switched on; and/or   iii) the aerosol generator being switched off.       

     Thus again, in so far as such a change of operation of the aerosol generator  40  occurs, the acoustic feedback  292  may provide a (confirmatory) indication that this has occurred, so the user can react in instances when this change in operation is otherwise unexpected. 
     Where the aerosol generator  40  is employed, the predetermined event in accordance with some embodiments may comprise the aerosol generator  40  exceeding a predetermined temperature, which could be indicative of there being a fault with the aerosol generator  40 , and/or could be indicative of a predetermined low amount of aerosol-generating material remaining in the aerosol provision system  1 . Thus in such embodiments, the acoustic feedback  292  may provide a (confirmatory) indication that the aerosol provision system  1  is subject to one of these conditions/statuses, or any other condition or status—adverse or otherwise. 
     As is clear from the embodiments disclosed at  FIGS.  1 - 6 B  at least, it is envisaged in accordance with some embodiments that any aerosol provision system  1  employed as part of the feedback provision system  300  may comprise an aerosol provision device  4 ; and a consumable  2  for releasably engaging with the aerosol provision device  4 , wherein the consumable  4  is configured for receiving aerosol-generating material for aerosolizing into the aerosol. 
     Noting the above disclosures therefore, it is clear that also provided herein may be an aerosol provision system  1  for generating an aerosol, wherein the aerosol provision system  1  is configured to wirelessly transmit a feedback signal  290  to an audio output device  200 , wherein the feedback signal  290  is configured for controlling the audio output device  200 . In this way, and in accordance with some embodiments, the feedback signal  290  may be configured to control the audio output device  200  to output acoustic feedback  292  (which could relate, in some embodiments, to any of the above noted purposes/applications for such feedback). 
     To be clear as well, it is noted that the present disclosure is also intended to be used as part of wider methods of delivering acoustic feedback, such as a method of delivering acoustic feedback  292  to an audio output device  200  of a user of an aerosol provision system  1 , using a feedback signal  290  transmitted from the aerosol provision system  1  to the audio output device  200 , wherein the feedback signal  290  is configured for controlling the audio output device  200 . 
     It will also be appreciated that the above disclosure may be used in the context of other aerosol provision system  1 , such as those disclosed with reference to the disclosure from  FIGS.  1 - 6 B , for retrofitting these aerosol provision system s 1  to be used as part of the herein recited feedback provision systems  300 . Accordingly, the present disclosure also is intended to cover such retrofitting applications, such as a method of retrofitting an aerosol provision system  1  (using appropriate alterations to the functionality of the aerosol provision system, e.g. in respect of any controller/control circuitry  18  therefrom) to deliver acoustic feedback  292  as part of a feedback provision system  300  comprising the aerosol provision system  1  and an audio output device  200 , the method comprising: providing the aerosol provision system  1  with instructions which, when executed by a controller  18  of the aerosol provision system  1 , cause the controller  18  to: generate a feedback signal which is configured to be wirelessly transmitted to an audio output device  200 , wherein the feedback signal  290  is configured for controlling the audio output device  200 ; and wirelessly transmitting the feedback signal  290  from the aerosol provision system  1  for allowing the feedback signal  290  to be received by the audio output device  200 . 
     Appreciating the foregoing therefore, there has accordingly been described a variety of different feedback provision systems, aerosol provision systems, and corresponding methods employing the same, which all look to provide for feedback signals and corresponding acoustic feedback arrangements which can be used to provide acoustic feedback from an aerosol provision system to a user thereof. 
     Bearing this in mind, the above noted disclosures may thus appreciably relate to the additional embodiments as set out in the following numbered clauses at the end of this specification, alongside the other noted embodiments from the below noted claims. 
     There has also been described a method of transmitting a feedback signal  290  from an aerosol provision system  1  to a hearing aid  200 , wherein the hearing aid  200  is configured to output acoustic feedback  292  in response to receiving the feedback signal  290  transmitted by the aerosol provision system  1 , wherein the feedback signal is configured for controlling the hearing aid  200 . In this way, the feedback signal  290  can used as a means to ultimately provide the user, via the hearing aid  200 , an indication of a current status of the aerosol provision system  1 . 
     In order to address various issues and advance the art, this disclosure shows by way of illustration various embodiments in which the claimed invention(s) may be practiced. The advantages and features of the disclosure are of a representative sample of embodiments only, and are not exhaustive and/or exclusive. They are presented only to assist in understanding and to teach the claimed invention(s). It is to be understood that advantages, embodiments, examples, functions, features, structures, and/or other aspects of the disclosure are not to be considered limitations on the disclosure as defined by the claims or limitations on equivalents to the claims, and that other embodiments may be utilized and modifications may be made without departing from the scope of the claims. Various embodiments may suitably comprise, consist of, or consist essentially of, various combinations of the disclosed elements, components, features, parts, steps, means, etc. other than those specifically described herein, and it will thus be appreciated that features of the dependent claims (or any herein recited dependent clauses) may be combined with features of the independent claims (or independent clauses) in combinations other than those explicitly set out in the claims or clauses. The disclosure may include other inventions not presently claimed, but which may be claimed in future. Accordingly, any permutation of the features from the claims may be combined as required, and/or may be combined with any permutation of the features from the herein recited clauses at the end of this specification. 
     Purely for completeness, with respect to any employed embodiments where the aerosol provision system  1  may be configured to wirelessly transmit the signal  290  to the audio output device  200 , it may be appreciated that in accordance with such embodiments, the aerosol provision system  1  and the corresponding audio output device  200  may be configured appropriately to effect this wireless communication. 
     For instance, in accordance with some of these embodiments, the aerosol provision system  1  may comprise a transmitter  96 , connected to the control circuitry  18  of the aerosol provision system  1 , for transmitting the wireless signal  290 . In this way, and as required, the audio output device  200  may then potentially also comprise a receiver  203  for receiving the wireless signal  290 . Where appropriate as well, the audio output device  200  in accordance with some embodiments may be also provided with a controller or control circuitry  204 , for receiving the signal  290  from the receiver  203 , for controlling the operation of any electroacoustic transducer  202  which is otherwise employed as part of the audio output device  200 . Appreciably however, it is not necessarily the case that such a controller or control circuitry  204  from the audio output device  200  be employed, in so far as the delivered signal  290  may in accordance with some embodiments directly comprise the audio output signal as noted previously. 
     Equally, and for completeness as well, in so far as any other forms of wireless communication are employed, such as Bluetooth®, a corresponding Bluetooth pairing arrangement may appreciably be provided between the aerosol provision system  1  and the audio output device  200  (and potentially also between any intermediary device  295  in the case of embodiments along the lines of the embodiment shown in  FIG.  9   ). 
     What follows is a consistory set of clauses: 
     1. A feedback provision system comprising: 
     an aerosol provision system for generating an aerosol; and 
     an audio output device for outputting acoustic feedback to a user of the aerosol provision system; 
     wherein the audio output device is configured to output the acoustic feedback in response to receiving a feedback signal which is initially wirelessly transmitted by the aerosol provision system, wherein the feedback signal is configured for controlling the audio output device. 
     2. A feedback provision system according to clause 1, wherein the audio output device is remotely located from the aerosol provision system.
 
3. A feedback provision system according to any preceding clause, wherein the aerosol provision system does not comprise the audio output device.
 
4. A feedback provision system according to any preceding clause, wherein the aerosol provision system is configured to wirelessly transmit the feedback signal directly to the audio output device.
 
5. A feedback provision system according to any preceding clause, wherein the audio output device comprises a loudspeaker.
 
6. A feedback provision system according to any preceding clause, wherein the audio output device comprises a headphone or earphone.
 
7. A feedback provision system according to any preceding clause, wherein the audio output device comprises a bone conduction audio output device.
 
8. A feedback provision system according to any preceding clause, wherein the audio output device comprises a hearing aid.
 
9. A feedback provision system according to any preceding clause, wherein the feedback signal comprises an audio output signal which is configured to be output by the audio output device as part of the acoustic feedback.
 
10. A feedback provision system according to any preceding clause, wherein the audio output device is configured to receive the feedback signal directly from the aerosol provision system.
 
11. A feedback provision system according to any preceding clause, wherein the feedback signal is configured to be transmitted by the aerosol provision system in response to a predetermined event being satisfied.
 
12. A feedback provision system according to any preceding clause, wherein the feedback signal is configured to be transmitted by the aerosol provision system in response to a predetermined event being determined as being satisfied by the aerosol provision system.
 
13. A feedback provision system according to clause 11 or 12, wherein the predetermined event comprises the aerosol provision system changing from a first mode of operation to a second mode of operation.
 
14. A feedback provision system according to any of clauses 11-13, wherein the predetermined event comprises at least one of:
 
     i) the aerosol provision system being switched on; and/or 
     ii) the aerosol provision system being switched off. 
     15. A feedback provision system according to any preceding clause, wherein the aerosol provision system comprises an aerosol generator, for aerosolizing aerosol-generating material, for generating the aerosol
 
16. A feedback provision system according to clause 15, when further dependent on any of clauses 11-14, wherein the predetermined event comprises any combination of:
 
     i) the aerosol generator being operated; 
     ii) the aerosol generator being switched on; and/or 
     iii) the aerosol generator being switched off. 
     17. A feedback provision system according to clause 15 or 16, when further dependent on any of clauses 11-14, wherein the predetermined event comprises the aerosol generator exceeding a predetermined temperature.
 
18. A feedback provision system according to any preceding clause, wherein the feedback signal is wirelessly transmitted by the aerosol provision system by Bluetooth.
 
19. A feedback provision system according to any preceding clause, wherein the aerosol provision system comprises:
 
     an aerosol provision device; and 
     a consumable for releasably engaging with the aerosol provision device, wherein the consumable is configured for receiving aerosol-generating material for aerosolizing into the aerosol. 
     20. A feedback provision system according to any preceding clause, wherein the acoustic feedback is configured to be indicative of a predetermined status of the aerosol provision system.
 
21. A feedback provision system according to clause 20, wherein the predetermined status of the aerosol provision system comprises a predetermined adverse status of the aerosol provision system.
 
22. An aerosol provision system for generating an aerosol, wherein the aerosol provision system is configured to wirelessly transmit a feedback signal to an audio output device; wherein the feedback signal is configured for controlling the audio output device.
 
23. An aerosol provision system according to clause 22, wherein the aerosol provision system does not comprise the audio output device.
 
24. An aerosol provision system according to clause 22 or 23, wherein the aerosol provision system is configured to wirelessly transmit the feedback signal directly to the audio output device.
 
25. An aerosol provision system according to any of clauses 22-24, wherein the feedback signal is configured to control the audio output device to output acoustic feedback.
 
26. An aerosol provision system according to any of clauses 22-25, wherein the feedback signal is configured to be wirelessly transmitted by the aerosol provision system in response to a predetermined event being determined as being satisfied by the aerosol provision system.
 
27. A method of delivering acoustic feedback in a feedback provision system, the method comprising:
 
     wirelessly transmitting a feedback signal, from an aerosol provision system for generating an aerosol, wherein the feedback signal is configured for controlling an audio output device; 
     receiving the feedback signal at the audio output device for outputting acoustic feedback to a user of the aerosol provision system; and 
     outputting the acoustic feedback from the audio output device. 
     28. A method of delivering acoustic feedback to an audio output device of a user of an aerosol provision system, using a feedback signal transmitted from the aerosol provision system to the audio output device, wherein the feedback signal is configured for controlling the audio output device.
 
29. A method of retrofitting an aerosol provision system to deliver acoustic feedback as part of a feedback provision system, the method comprising:
 
     providing the aerosol provision system with instructions which, when executed by a controller of the aerosol provision system, cause the controller to: 
     generate a feedback signal which is configured to be wirelessly transmitted to an audio output device, wherein the feedback signal is configured for controlling the audio output device; and 
     wirelessly transmitting the feedback signal from the aerosol provision system for allowing the feedback signal to be received by the audio output device. 
     30. A method according to clause 27 or 28, wherein the feedback signal is configured to be transmitted by the aerosol provision system in response to a predetermined event being satisfied.
 
31. A method according to any of clauses 27-30, wherein the feedback signal is configured to be transmitted by the aerosol provision system in response to a predetermined event being determined as being satisfied by the aerosol provision system.
 
32. A method according to any of clauses 27-31, wherein the feedback signal is directly transmitted from the aerosol provision system to the audio output device.
 
33. A method according to any of clauses 27-32, wherein the aerosol provision system does not comprise the audio output device. 34. A method according to any of clauses 27-33, wherein the audio output device comprises a loudspeaker.
 
35. A method according to any of clauses 27-34, wherein the audio output device comprises a headphone or earphone.
 
36. A method according to any of clauses 27-35, wherein the audio output device comprises a bone conduction audio output device
 
37. A method according to any of clauses 27-36, wherein the audio output device comprises a hearing aid.
 
38. A method according to any of clauses 27-37, wherein the feedback signal is transmitted by Bluetooth.