Patent Description:
Electronic aerosol provision systems such as electronic cigarettes (e-cigarettes) generally contain an aerosol precursor material, such as a reservoir of a source liquid containing a formulation, typically including nicotine, or a solid material such a tobacco-based product, from which an aerosol is generated for inhalation by a user, for example through heat vaporisation. Thus, an aerosol provision system will typically comprise a vaporiser, e.g. a heating element, arranged to vaporise a portion of precursor material to generate an aerosol in an aerosol generation region of an air channel through the aerosol provision system. As a user inhales on the device and electrical power is supplied to the vaporiser, air is drawn into the device through one or more inlet holes and along the air channel to the aerosol generation region, where the air mixes with the vaporised precursor material and forms a condensation aerosol. The air drawn through the aerosol generation region continues along the air channel to a mouthpiece opening, carrying some of the aerosol with it, and out through the mouthpiece opening for inhalation by the user.

It is common for aerosol provision systems to comprise a modular assembly, often having two main functional parts, namely a control unit and disposable / replaceable cartridge part. Typically the cartridge part will comprise the consumable aerosol precursor material and the vaporiser (atomiser), while the control unit part will comprise longer-life items, such as a rechargeable battery, device control circuitry, activation sensors and user interface features. The control unit may also be referred to as a reusable part or battery section and the replaceable cartridge may also be referred to as a disposable part or cartomiser.

The control unit and cartridge are mechanically coupled together at an interface for use, for example using a screw thread, bayonet, latched or friction fit fixing. When the aerosol precursor material in a cartridge has been exhausted, or the user wishes to switch to a different cartridge having a different aerosol precursor material, the cartridge may be removed from the control unit and a replacement cartridge may be attached to the device in its place.

A potential drawbacks for cartridges containing liquid aerosol precursor (e-liquid) is the risk of leakage. An e-cigarette cartridge will typically have a mechanism, e.g. a capillary wick, for drawing aerosolisable material from an aerosolisable material reservoir to a vaporiser located in an air path / channel connecting from an air inlet to an aerosol outlet for the cartridge. Because there is a fluid transport path from the aerosolisable material reservoir into the open air channel through the cartridge, there is a corresponding risk of aerosolisable material leaking from the cartridge. Leakage is undesirable both from the perspective of the end user naturally not wanting to get the e-liquid on their hands or other items, and also from a reliability perspective, since leakage from an end of the cartridge connected to the control unit may damage the control unit, for example due to corrosion. Some approaches to reduce the risk of leakage may involve restricting the flow of aerosolisable material to the vaporiser, for example by tightly clamping a wick where it enters the air channel. In normal use, the aerosolisable material taken up by the wick is sufficient to keep the vaporiser cool (i.e., at an ideal operating temperature), but when the aerosolisable material taken up is insufficient (e.g., when the aerosolisable material in the reservoir runs low) this can in some scenarios give rise to overheating and undesirable flavours.

Existing prior art includes <CIT>, which relates to an inhalator and atomizing component thereof; and <CIT>, which relates to a molding die for an atomizer and a casing thereof.

Various approaches are described herein which seek to help address or mitigate some of the issues discussed above.

The invention is defined by the scope of the appended claims.

Embodiments of the invention will now be described, by way of example only, with reference to the accompanying <FIG>, <FIG>, <FIG>, and <FIG>. <FIG>, <FIG>, <FIG>, and <FIG>, represent embodiments which are not encompassed by the wording of the claims but are considered as useful for understanding the invention.

The present disclosure relates to non-combustible aerosol provision systems, which may also be referred to as aerosol provision systems, such as e-cigarettes. According to the present disclosure, a "non-combustible" aerosol provision system is one where a constituent aerosolisable material of the aerosol provision system (or component thereof) is not combusted or burned in order to facilitate delivery to a user. Aerosolisable 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.

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 aerosol provision system / device and electronic aerosol provision system / device. 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 aerosolisable material is not a requirement.

In some embodiments, the non-combustible aerosol provision system is a hybrid system to generate aerosol using a combination of aerosolisable materials, one or a plurality of which may be heated. In some embodiments, the hybrid system comprises a liquid or gel aerosolisable material and a solid aerosolisable material. The solid aerosolisable material may comprise, for example, tobacco or a non-tobacco product.

Typically, the non-combustible aerosol provision system may comprise a non-combustible aerosol provision device and an article for use with the non-combustible aerosol provision device. However, it is envisaged that articles which themselves comprise a means for powering an aerosol generating component may themselves form the non-combustible aerosol provision system.

In some embodiments, the article for use with the non-combustible aerosol provision device may comprise an aerosolisable material (or aerosol precursor material), an aerosol generating component (or vaporiser), an aerosol generating area, a mouthpiece, and/or an area for receiving aerosolisable material.

In some embodiments, the aerosol generating component is a heater capable of interacting with the aerosolisable material so as to release one or more volatiles from the aerosolisable material to form an aerosol. In some embodiments, the aerosol generating component is capable of generating an aerosol from the aerosolisable material without heating. For example, the aerosol generating component may be capable of generating an aerosol from the aerosolisable material without applying heat thereto, for example via one or more of vibrational, mechanical, pressurisation or electrostatic means.

In some embodiments, the substance to be delivered may be an aerosolisable 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 aerosolisable 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 "flavour" and/or "flavourant" 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 flavours, flavourants, cooling agents, heating agents, and/or sweetening agents. They may include naturally occurring flavour 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), flavour 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), flavour 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 flavour comprises menthol, spearmint and/or peppermint. In some embodiments, the flavour comprises flavour components of cucumber, blueberry, citrus fruits and/or redberry. In some embodiments, the flavour comprises eugenol. In some embodiments, the flavour comprises flavour components extracted from tobacco. In some embodiments, the flavour 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-<NUM>.

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, <NUM>,<NUM>-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, colouring agents, preservatives, binders, fillers, stabilizers, and/or antioxidants.

As noted above, aerosol provision systems (e-cigarettes) often comprise a modular assembly including both a reusable part (control unit) and a replaceable (disposable) 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 comprise this kind of generally elongate two-part device employing disposable cartridges. 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.

<FIG> is a schematic perspective view of an example aerosol provision system / device (e-cigarette) <NUM> 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> (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 <NUM> comprises two main components, namely a cartridge <NUM> and a control unit <NUM>. The control unit <NUM> and the cartridge <NUM> are shown separated in <FIG>, but are coupled together when in use.

The cartridge <NUM> and control unit <NUM> 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 <NUM> represented in <FIG>, the cartridge comprises a mouthpiece end <NUM> and an interface end <NUM> and is coupled to the control unit by inserting an interface end portion <NUM> at the interface end of the cartridge into a corresponding receptacle <NUM> / receiving section of the control unit. The interface end portion <NUM> of the cartridge is a close fit to be receptacle <NUM> and includes protrusions <NUM> which engage with corresponding detents in the interior surface of a receptacle wall <NUM> defining the receptacle <NUM> to provide a releasable mechanical engagement between the cartridge and the control unit. An electrical connection is established between the control unit and the cartridge via a pair of electrical contacts on the bottom of the cartridge (not shown in <FIG>) and corresponding sprung contact pins in the base of the receptacle <NUM> (not shown in <FIG>). 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 control unit 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 <NUM> has a generally elongate shape extending along a longitudinal axis L. When the cartridge is coupled to the control unit, the overall length of the electronic cigarette in this example (along the longitudinal axis) is around <NUM>. The overall length of the control unit is around <NUM> and the overall length of the cartridge is around <NUM> (i.e. there is around <NUM> of overlap between the interface end portion <NUM> of the cartridge and the receptacle <NUM> of the control unit 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 <NUM> and a thickness of around <NUM>. The end of the cartridge has a width of around <NUM> and a thickness of around <NUM>, whereas the other end of the electronic cigarette has a width of around <NUM> and a thickness of around <NUM>. 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 control unit <NUM> 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>, the control unit <NUM> comprises a plastic outer housing <NUM> including the receptacle wall <NUM> that defines the receptacle <NUM> for receiving the end of the cartridge as noted above. The outer housing <NUM> of the control unit <NUM> in this example has a generally oval cross section conforming to the shape and size of the cartridge <NUM> at their interface to provide a smooth transition between the two parts. The receptacle <NUM> and the end portion <NUM> of the cartridge <NUM> are symmetric when rotated through <NUM>° so the cartridge can be inserted into the control unit in two different orientations. The receptacle wall <NUM> includes two control unit air inlet openings <NUM> (i.e. holes in the wall). These openings <NUM> are positioned to align with an air inlet <NUM> for the cartridge when the cartridge is coupled to the control unit. A different one of the openings <NUM> aligns with the air inlet <NUM> 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 couplable to the control unit in only one orientation while other implementations may have a higher degree of rotational symmetry such that the cartridge is couplable to the control unit in more orientations.

The control unit further comprises a battery <NUM> for providing operating power for the electronic cigarette, control circuitry <NUM> for controlling and monitoring the operation of the electronic cigarette, a user input button <NUM>, an indicator light <NUM>, and a charging port <NUM>.

The battery <NUM> 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 <NUM> may be recharged through the charging port <NUM>, which may, for example, comprise a USB connector.

The input button <NUM> 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 <NUM> 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 colours and / or different flash sequences in accordance with generally conventional techniques.

The control circuitry <NUM> 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) <NUM> may be considered to logically comprise various sub-units / circuitry elements associated with different aspects of the electronic cigarette's operation. For example, depending on the functionality provided in different implementations, the control circuitry <NUM> 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 <NUM> 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> is an exploded schematic perspective view of the cartridge <NUM> (exploded along the longitudinal axis L). The cartridge <NUM> comprises a housing part <NUM>, an air channel seal <NUM>, a dividing wall element <NUM>, an outlet tube <NUM>, a vaporiser/heating element <NUM>, an aerosolisable material transport element <NUM>, a plug <NUM>, and an end cap <NUM> with contact electrodes <NUM>.

<FIG> schematically represents some of these components in more detail.

<FIG> is a schematic cut-away view of the housing part <NUM> through the longitudinal axis L where the housing part <NUM> is thinnest. <FIG> is a schematic cut-away view of the housing part <NUM> through the longitudinal axis L where the housing part <NUM> is widest. <FIG> is a schematic view of the housing part along the longitudinal axis L from the interface end <NUM> (i.e. viewed from below in the orientation of <FIG>).

<FIG> is a schematic perspective view of the dividing wall element <NUM> as seen from below. <FIG> is a schematic cross-section through an upper part of the dividing wall element <NUM> as viewed from below.

<FIG> is a schematic perspective view of the plug <NUM> from above and <FIG> is a schematic perspective view of the plug <NUM> from below. <FIG> is a schematic view of the plug <NUM> along the longitudinal axis L seen from the mouthpiece end <NUM> of the cartridge (i.e. viewed from above for the orientation in <FIG> and <FIG>).

<FIG> is a schematic perspective view of the end cap <NUM> from above. <FIG> is a schematic view of the end cap <NUM> along the longitudinal axis L seen from the mouthpiece end <NUM> of the cartridge (i.e. from above).

The housing part <NUM> in this example comprises a housing outer wall <NUM> and a housing inner tube <NUM> which in this example are formed from a single moulding of polypropylene. The housing outer wall <NUM> defines the external appearance of the cartridge <NUM> and the housing inner tube <NUM> defines a part the air channel through the cartridge. The housing part is open at the interface end <NUM> of the cartridge and closed at the mouthpiece end <NUM> of the cartridge except for a mouthpiece opening / aerosol outlet <NUM> in fluid communication with the housing inner tube <NUM>. The housing part <NUM> includes an opening in a sidewall which provides the air inlet <NUM> for the cartridge. The air inlet <NUM> in this example has an area of around <NUM><NUM>. The outer surface of the outer wall <NUM> of the housing part <NUM> includes the protrusions <NUM> discussed above which engage with corresponding detents in the interior surface of the receptacle wall <NUM> defining the receptacle <NUM> to provide a releasable mechanical engagement between the cartridge and the control unit. The inner surface of the outer wall <NUM> of the housing part includes further protrusions <NUM> which act to provide an abutment stop for locating the dividing wall element <NUM> along the longitudinal axis L when the cartridge is assembled. The outer wall <NUM> of the housing part <NUM> further comprises holes which provide latch recesses <NUM> arranged to receive corresponding latch projections <NUM> in the end cap to fix the end cap to be housing part when the cartridge is assembled.

The outer wall <NUM> of the housing part <NUM> includes a double-walled section <NUM> that defines a gap <NUM> in fluid communication with the air inlet <NUM>. The gap <NUM> provides a portion of the air channel through the cartridge. In this example the doubled-walled section <NUM> of the housing part <NUM> is arranged so the gap defines an air channel running within the housing outer wall <NUM> parallel to the longitudinal axis with a cross-section in a plane perpendicular to the longitudinal axis of around <NUM><NUM>. The gap / portion of air channel <NUM> defined by the double-walled section of the housing part extends down to the open end of the housing part <NUM>.

The air channel seal <NUM> is a silicone moulding generally in the form of a tube having a through hole <NUM>. The outer wall of the air channel seal <NUM> includes circumferential ridges <NUM> and an upper collar <NUM>. The inner wall of the air channel seal <NUM> also includes circumferential ridges, but these are not visible in <FIG>. When the cartridge is assembled the air channel seal <NUM> is mounted to the housing inner tube <NUM> with an end of the housing inner tube <NUM> extending partly into the through hole <NUM> of the air channel seal <NUM>. The through hole <NUM> in the air channel seal has a diameter of around <NUM> in its relaxed state whereas the end of the housing inner tube <NUM> has a diameter of around <NUM> so that a seal is formed when the air channel seal <NUM> is stretched to accommodate the housing inner tube <NUM>. This seal is facilitated by the ridges on the inner surface of the air channel seal <NUM>.

The outlet tube <NUM> comprises a tubular section, for instance made of ANSI <NUM> stainless steel or polypropylene, with an internal diameter of around <NUM> and a wall thickness of around <NUM>. The bottom end of the outlet tube <NUM> includes a pair of diametrically opposing slots <NUM> with an end of each slot having a semi-circular recess <NUM>. When the cartridge is assembled the outlet tube <NUM> mounts to the outer surface of the air channel seal <NUM>. The outer diameter of the air channel seal is around <NUM> in its relaxed state so that a seal is formed when the air channel seal <NUM> is compressed to fit inside the outlet tube <NUM>. This seal is facilitated by the ridges <NUM> on the outer surface of the air channel seal <NUM>. The collar <NUM> on the air channel seal <NUM> provides a stop for the outlet tube <NUM>.

The aerosolisable material transport element <NUM> comprises a capillary wick and the vaporiser <NUM> 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 vaporiser comprises electrical leads <NUM> which pass through holes in the plug <NUM> to contact electrodes <NUM> mounted to the end cap <NUM> to allow power to be supplied to the vaporiser via the electrical interface the established when the cartridge is connected to a control unit. The vaporiser leads <NUM> 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 <NUM> comprises a nickel iron alloy wire and the wick <NUM> comprises a glass fibre bundle. The vaporiser and aerosolisable 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 aerosolisable material transport element and vaporiser is not of primary significance to the principles described herein.

When the cartridge is assembled, the wick <NUM> is received in the semi-circular recesses <NUM> of the outlet tube <NUM> 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 <NUM>.

The plug <NUM> in this example comprises a single moulding of silicone, may be resilient. The plug comprises a base part <NUM> with an outer wall <NUM> extending upwardly therefrom (i.e. towards the mouthpiece end of the cartridge). The plug further comprises an inner wall <NUM> extending upwardly from the base part <NUM> and surrounding a through hole <NUM> through the base part <NUM>.

The outer wall <NUM> of the plug <NUM> conforms to an inner surface of the housing part <NUM> so that when the cartridge is assembled the plug in <NUM> forms a seal with the housing part <NUM>. The inner wall <NUM> of the plug <NUM> conforms to an inner surface of the outlet tube <NUM> so that when the cartridge is assembled the plug <NUM> also forms a seal with the outlet tube <NUM>. The inner wall <NUM> includes a pair of diametrically opposing slots <NUM> with the end of each slot having a semi-circular recess <NUM>. 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 <NUM> is a cradle section <NUM> shaped to receive a section of the aerosolisable material transport element <NUM> when the cartridge is assembled. The slots <NUM> and semi-circular recesses <NUM> provided by the inner wall of the plug <NUM> and the slots <NUM> and semi-circular recesses <NUM> of the outlet tube <NUM> are aligned so that the slots <NUM> in the outlet tube <NUM> accommodate respective ones of the cradles <NUM> with the respective semi-circular recesses in the outlet tube and plug cooperating to define holes through which the aerosolisable material transport element passes. The size of the holes provided by the semi-circular recesses through which the aerosolisable material transport element passes correspond closely to the size and shape of the aerosolisable material transport element, but are slightly smaller so a degree of compression is provided by the resilience of the plug <NUM>. This allows aerosolisable material to be transported along the aerosolisable material transport element by capillary action while restricting the extent to which aerosolisable material which is not transported by capillary action can pass through the openings. As noted above, the plug <NUM> includes further openings <NUM> in the base part <NUM> through which the contact leads <NUM> for the vaporiser pass when the cartridge is assembled. The bottom of the base part of the plug includes spacers <NUM> which maintain an offset between the remaining surface of the bottom of the base part and the end cap <NUM>. These spacers <NUM> include the openings <NUM> through which the electrical contact leads <NUM> for the vaporiser pass.

The end cap <NUM> comprises a polypropylene moulding with a pair of gold-plated copper electrode posts <NUM> mounted therein.

The ends of the electrode posts <NUM> on the bottom side of the end cap are close to flush with the interface end <NUM> of the cartridge provided by the end cap <NUM>. These are the parts of the electrodes to which correspondingly aligned sprung contacts in the control unit connect when the cartridge is assembled and connected to the control unit. The ends of the electrode posts on the inside of the cartridge extend away from the end cap <NUM> and into the holes <NUM> in the plug <NUM> through which the contact leads <NUM> pass. The electrode posts are slightly oversized relative to the holes <NUM> and include a chamfer at their upper ends to facilitate insertion into the holes <NUM> in the plug where they are maintained in pressed contact with the contact leads for the vaporiser by virtue of the plug.

The end cap has a base section <NUM> and an upstanding wall <NUM> which conforms to the inner surface of the housing part <NUM>. The upstanding wall <NUM> of the end cap <NUM> is inserted into the housing part <NUM> so the latch projections <NUM> engage with the latch recesses <NUM> in the housing part <NUM> to snap-fit the end cap <NUM> to the housing part when the cartridge is assembled. The top of the upstanding wall <NUM> of the end cap <NUM> abuts a peripheral part of the plug <NUM> and the lower face of the spacers <NUM> on the plug also abut the base section <NUM> of the plug so that when the end cap <NUM> is attached to the housing part it presses against the resilient part <NUM> to maintain it in slight compression.

The base portion <NUM> of the end cap <NUM> includes a peripheral lip <NUM> beyond the base of the upstanding wall <NUM> 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 <NUM> which aligns with a corresponding locating hole <NUM> in the plug to help establish their relative location during assembly.

The dividing wall element <NUM> comprises a single moulding of polypropylene and includes a dividing wall <NUM> and a collar <NUM> formed by projections from the dividing wall <NUM> in the direction towards the interface end of the cartridge. The dividing wall element <NUM> has a central opening <NUM> through which the outlet tube <NUM> passes (i.e. the dividing wall is arranged around the outlet tube <NUM>). In some embodiments, the dividing wall element <NUM> may be integrally formed with the outlet tube <NUM>. When the cartridge is assembled, the upper surface of the outer wall <NUM> of the plug <NUM> engages with the lower surface of the dividing wall <NUM>, and the upper surface of the dividing wall <NUM> in turn engages with the projections <NUM> on the inner surface of the outer wall <NUM> of the housing part <NUM>. Thus, the dividing wall <NUM> prevents the plug from being pushed too far into the housing part <NUM> - i.e. the dividing wall <NUM> is fixedly located along the longitudinal axis of the cartridge by the protrusions <NUM> in the housing part and so provides the plug with a fixed surface to push against. The collar <NUM> formed by projections from the dividing wall includes a first pair of opposing projections / tongues <NUM> which engage with corresponding recesses on an inner surface of the outer wall <NUM> of the plug <NUM>. The protrusions from the dividing wall <NUM> further provide a pair of cradle sections <NUM> configured to engage with corresponding ones of the cradle sections <NUM> in the part <NUM> when the cartridge is assembled to further define the opening through which the aerosolisable material transport element passes.

When the cartridge is assembled an air channel extending from the air inlet <NUM> to the aerosol outlet <NUM> through the cartridge is formed. Starting from the air inlet <NUM> in the side wall of the housing part <NUM>, a first section of the air channel is provided by the gap <NUM> formed by the double-walled section <NUM> in the outer wall <NUM> of the housing part <NUM> and extends from the air inlet <NUM> towards the interface end <NUM> of the cartridge and past the plug <NUM>. A second portion of the air channel is provided by the gap between the base of the plug <NUM> and the end cap <NUM>. A third portion of the air channel is provided by the hole <NUM> through the plug <NUM>. A fourth portion of the air channel is provided by the region within the inner wall <NUM> of the plug and the outlet tube around the vaporiser <NUM>. 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 <NUM> 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 <NUM>. A sixth portion of the air channel is provided by the outer housing inner tube <NUM> which connects the air channel to the aerosol outlet <NUM>. 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 <NUM> for aerosolisable material is formed by the space outside the air channel and inside the housing part <NUM>. 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 aerosolisable material, for example in terms of its composition, is not of primary significance to the principles described herein, and in general any conventional aerosolisable material of the type normally used in electronic cigarettes may be used. The present disclosure may refer to a liquid as the aerosolisable material, which as mentioned above may be a conventional e-liquid. However, the principles of the present disclosure apply to any aerosolisable 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 <NUM>. The reservoir includes a first region above the dividing wall <NUM> and a second region below the dividing wall <NUM> within the space formed between the air channel and the outer wall of the plug. The aerosolisable material transport element (capillary wick) <NUM> passes through openings in the wall of the air channel provided by the semi-circular recesses <NUM>, <NUM> in the plug <NUM> and the outlet tube <NUM> and the cradle sections <NUM>, <NUM> in the plug <NUM> and the dividing wall element <NUM> that engage with one another as discussed above. Thus, the ends of the aerosolisable material transport element extend into the second region of the reservoir from which they draw aerosolisable material through the openings in the air channel to the vaporiser <NUM> for subsequent vaporisation.

In normal use, the cartridge <NUM> is coupled to the control unit <NUM> and the control unit activated to supply power to the cartridge via the contact electrodes <NUM> in the end cap <NUM>. Power then passes through the connection leads <NUM> to the vaporiser <NUM>. The vaporiser is thus electrically heated and so vaporises a portion of the aerosolisable material from the aerosolisable material transport element in the vicinity of the vaporiser. This generates aerosol in the aerosol generation region of the air path. Aerosolisable material that is vaporised from the aerosolisable material transport element is replaced by more aerosolisable material drawn from the reservoir by capillary action. While the vaporiser is activated, a user inhales on the mouthpiece end <NUM> of the cartridge. This causes air to be drawn through whichever control unit air inlet <NUM> aligns with the air inlet <NUM> of the cartridge (which will depend on the orientation in which the cartridge was inserted into the control unit receptacle <NUM>). Air then enters the cartridge through the air inlet <NUM>, passes along the gap <NUM> in the double-walled section <NUM> of the housing part <NUM>, passes between the plug <NUM> and the end cap <NUM> before entering the aerosol generation region surrounding the vaporiser <NUM> through the hole <NUM> in the base part <NUM> of the plug <NUM>. The incoming air mixes with aerosol generated from the vaporiser to form a condensation aerosol, which is then drawn along the outlet tube <NUM> and the housing part inner <NUM> before exiting through the mouthpiece outlet/aerosol outlet <NUM> for user inhalation.

With reference to <FIG>, there is shown schematically a cross section view of a modified cartridge <NUM> for use with the control unit <NUM> shown in <FIG> to form an aerosol provision system in accordance with certain embodiments of the disclosure. The cartridge <NUM> shown in <FIG> is based on the construction of the cartridge <NUM> shown in <FIG>, and comprises similar components as set out by the reference numerals that are common to both sets of Figures. For instance, the cartridge <NUM> defines a reservoir <NUM> which extends around an aerosol outlet tube <NUM>. In accordance with such embodiments, the reservoir <NUM> may be annular, and is configured for containing aerosolisable material for aerosolising.

In accordance with some embodiments, the reservoir <NUM> may comprise a first end 31A which is proximal the aerosol outlet <NUM> of the cartridge <NUM>, and a second end 31B which is proximal the vaporiser <NUM>. The cartridge in accordance with some embodiments may comprise an elliptical cross section <NUM>, which may be perpendicular to the longitudinal axis L of the cartridge <NUM> (as shown in <FIG>). As shown in <FIG>, the elliptical cross section <NUM> defines a major axis and a minor axis, which are axes that may be perpendicular to the longitudinal axis L of the cartridge <NUM>.

With reference to the cartridge <NUM> shown in <FIG>, a first modification over the cartridge <NUM> shown in <FIG> is the introduction of an aerosolisable-material-level observation means <NUM> for allowing a user to observe a level of aerosolisable material <NUM> inside the reservoir <NUM>. The aerosolisable-material-level observation means <NUM> may include one or more features and these will now be described. In accordance with some embodiments, the aerosolisable-material-level observation means <NUM> comprises a portion <NUM> of the cartridge <NUM>. In accordance with some embodiments, the portion <NUM> of the cartridge comprises a window <NUM> for viewing into the reservoir <NUM>. Such a window is shown best in <FIG>, where the window <NUM> is operable to allow a user to observe a level of aerosolisable material inside the reservoir <NUM>. To assist with the viewing of aerosolisable material inside the reservoir, the portion <NUM> of the cartridge and/or the window <NUM> may be translucent or transparent. A possible material for the portion <NUM> of the cartridge is plastic, such as polypropylene.

It is envisaged that the portion <NUM> of the cartridge may be located at any part, or combination of parts (noting such parts may, or may not, be located next to each other), of the cartridge <NUM>. In some particular embodiments, the portion <NUM> of the cartridge <NUM> may be located on any visible surface(s) and/or visible edge(s) of the cartridge <NUM>. For instance, in some embodiments, the portion <NUM> of the cartridge <NUM> may be located on any one or combination of a first, front, surface 209A; a second, rear, surface 209B opposite the front surface 209B; and/or a side surface(s) 209C;209D of the cartridge <NUM> which are located between the front surface 209A and the rear surface 209B. The portion <NUM> of the cartridge <NUM> may additionally/alternatively be located on any one or combination of edge(s) from the cartridge <NUM>, for instance a first edge 211A and/or a second edge 211B which are located between the first surface 209A and the second surface 209B, such as located at one or both intersections of the elliptical cross section <NUM> with the major and/or minor axis.

In accordance with some embodiments, the portion <NUM> of the cartridge <NUM> may form a first wall portion <NUM> of the reservoir <NUM>, as shown in <FIG> with a reduced thickness. In such embodiments, the first wall portion <NUM> may have a maximum thickness T<NUM> which is no more than any of <NUM>; <NUM>; <NUM>; <NUM>; <NUM>; or <NUM>. In that way, the reduced thickness may assist with the user being able to observe the level of aerosolisable material inside the reservoir. For some embodiments of the cartridge <NUM>, the reservoir may further comprise a second wall portion <NUM>. There, the first wall portion <NUM> may be more transparent/translucent than the respective transparency/translucency of the second wall portion <NUM>. In that way the portion <NUM> of the cartridge <NUM>, and the first wall portion <NUM>, act to provide the aerosolisable-material-level observation means <NUM>. In terms of the shape/structure of the first wall portion <NUM> and the second wall portion <NUM>, it is envisaged that each wall portion may span any part, or combination of parts (noting such parts may, or may not, be located next to each other), of the cartridge <NUM>. For instance, in one embodiment, the first and/or second wall portion <NUM>;<NUM> may be located at one or both intersections of the elliptical cross section <NUM> with the major axis. Equally, the first and/or second wall portion <NUM>;<NUM> might be located at one or both intersections of the elliptical cross section <NUM> with the minor axis.

In some embodiments, such as the embodiment shown in <FIG>, the first wall portion <NUM> may define a recess <NUM> on an outside surface <NUM> of the cartridge <NUM>. In some embodiments, such as that shown in <FIG>, the first wall portion <NUM> may define a recess <NUM> inside the reservoir <NUM>. As shown in that embodiment, and also the embodiment shown in <FIG>, the first wall portion <NUM> may comprise a maximum thickness which is less than the maximum thickness of the second wall portion <NUM>. In some implementations, the thickness of the first wall portion <NUM> is uniform over the extent of the first wall portion <NUM> to help provide a consistent transparency/translucency over the whole of wall portion <NUM>.

The aerosolisable-material-level observation means <NUM>, which allows a user to observe a level of aerosolisable material inside the reservoir <NUM>, may in some embodiments be achieved by varying the level of pigmentation of a portion of the cartridge in a way that allows this portion of the cartridge <NUM> to be more easily seen through. Accordingly, using the embodiments of cartridges shown in <FIG> as an example, in accordance with some embodiments the first wall portion <NUM> may comprise a first concentration of coloured pigment, and the second wall portion <NUM> comprise a second concentration of coloured pigment, wherein the first concentration is less than the second concentration. In such embodiments, the first wall portion <NUM> need not necessarily be thinner than the second wall portion <NUM> to achieve the aerosolisable-material-level observation means, since that may be achieved through the reduced levels of pigment used in the first wall portion.

In particular embodiments, the first concentration of coloured pigment may be no more than <NUM> of pigment per <NUM> of the first wall portion. In other embodiments, the <NUM> value may be <NUM>, or <NUM>. These reduced levels of pigment in the first wall portion <NUM> present surprisingly effective levels of pigment that provide for an aerosolisable-material-level observation means <NUM> with good visibility characteristics.

To help contrast with the visibility levels provided in the first wall portion <NUM> through its reduced levels of pigment concentration, in accordance with some embodiments, the second concentration of coloured pigment in the second wall portion <NUM> may be more than <NUM> of pigment per <NUM> of the second wall portion. In other embodiments, the <NUM> value relating to this second wall portion <NUM> may be <NUM>, or <NUM>.

It will be appreciated in the above embodiments that any particular pigment(s) may be used as required for each portion of the cartridge to provide the required visibility properties for each such portion. In one very particular embodiment, the pigment used may comprise one or more colourants, and/or opaque material(s) which affect the visibility properties of the portion of the cartridge. For example, the pigment may comprise Manganese Ferrite black pigment (<NPL>).

In terms of the materials used in the cartridge <NUM>, in some embodiments the first wall portion <NUM> and/or the second wall portion <NUM> may comprise/be made of plastic. In some embodiments, the first wall portion <NUM> may comprise a material that is different from the material of the second wall portion <NUM>. By selecting an appropriate material for each portion of the cartridge, an appropriate aerosolisable-material-level observation means <NUM> may be effectively provided.

A modified version of the cartridge <NUM> shown in <FIG> is shown in the cartridge <NUM> of <FIG>. With reference <FIG>, it is envisaged that, according to the invention, the cartridge comprises a second window <NUM> for allowing light into the reservoir <NUM>. In some embodiments, as shown in that of <FIG>, the second window <NUM> may comprise a different shape (for instance circular) than the shape of the first window <NUM>, although from an aesthetic point of view, the second window <NUM> may in some implementations have the same or similar shape to the first window <NUM>. Indeed, the shape of each window may take several forms. For instance, in some embodiments, such as those shown in <FIG> and <FIG>, the first window <NUM> may be elongate. In that way, a wide variety of different levels of aerosolisable material can be observed through the first window <NUM> as the quantity of aerosolisable material in the reservoir <NUM> diminishes in use of the cartridge <NUM>.

To better prevent the user from obscuring the second window <NUM> whilst using the first window <NUM>, in accordance with the invention, the first window <NUM> is located on a first side <NUM> of the reservoir <NUM>, and the second window <NUM> located on a second side <NUM>, opposite the first side <NUM>, of the reservoir <NUM>, as is shown in <FIG>. Having the first and second windows opposite one another may increase the amount of light that passes through the second window <NUM> into the reservoir <NUM>, and then out of the first window to the user's eye for instance. This may be compared to when the windows <NUM>;<NUM> are offset where any light entering the cartridge <NUM> may interact with the walls of the reservoir <NUM> before exiting the first window <NUM>. Increasing the amount of light exiting the first window <NUM> may increase the user's ability to detect the level of aerosolisable material.

The dimensions of each window may be varied depending on the application and size of the cartridge <NUM>. In accordance with some embodiments, the first window <NUM> and/or the second window <NUM> may comprise a maximum dimension of no more than <NUM>, preferably no more than <NUM>, and more preferably no more than <NUM>. The phrase maximum dimension here means that none of the maximum length (Lmax)/width (Wmax)/thickness (Tmax) of the respective window must be more than the quoted amount in millimetres.

Turning to the version of the cartridge <NUM> shown in <FIG>, in accordance with some embodiments of the cartridge <NUM>, the cartridge <NUM> may further comprise a covering means <NUM> for inhibiting the visibility of at least one portion <NUM> of the cartridge <NUM> by the user. In accordance with some embodiments, the covering means <NUM> may comprise an opaque sheet(s) of material affixed to a surface of the cartridge, such as a label <NUM> as shown in <FIG>. In some embodiments, the covering means may comprise an opaque material, such as an opaque plastic or metal, forming part of the cartridge.

The provision of the covering means <NUM> focusses the user's vision to the aerosolisable-material-level observation means <NUM> which allows for the level of aerosolisable material <NUM> inside the reservoir <NUM> to be observed. Accordingly, the provision of the covering means <NUM> makes it easier for the user to view the level of aerosolisable material <NUM> inside the reservoir <NUM>.

To assist with the functioning of the covering means <NUM> to focus the user's vision to the aerosolisable-material-level observation means <NUM>, the covering means <NUM> inhibits the visibility of at least one portion <NUM> of the cartridge <NUM>. In some embodiments, the portion <NUM> comprises at least one of the vaporiser <NUM>; the aerosol generation region; and/or the air channel.

A further modified version of the cartridge <NUM> is shown in <FIG>. As shown in these Figures, it is envisaged that in some embodiments of the cartridge <NUM>, the aerosolisable-material-level observation means <NUM> may comprise a plurality of markings <NUM> on the cartridge <NUM> for allowing the user to gauge the level of aerosolisable material <NUM> inside the reservoir <NUM> against these plurality of markings <NUM>. The markings <NUM> may take any required shape/size as suited to the cartridge <NUM>, and may be located on an external and/or an internal surface (such as any of the surfaces 209A;209B;209C;209D) or edge (such as the edges 211A;211B between the front surface 209A and the rear surface 209B) of the cartridge <NUM>, such as on a surface inside the reservoir <NUM> which is also visible from the portion <NUM> of the cartridge <NUM>. In a particular embodiment, the plurality of markings <NUM> may be located on a surface of the outlet tube <NUM>;<NUM>. In some embodiments, the plurality of markings may comprise a plurality of parallel lines <NUM>.

To improve the visibility of the plurality of markings <NUM>, in accordance with some embodiments the plurality of markings may be surrounded by a portion <NUM> of the cartridge <NUM> that is transparent and/or translucent. In that respect, the plurality of markings may be opaque.

For gauging/quantifying the level of aerosolisable material <NUM> inside the reservoir <NUM>, in some embodiments the plurality of markings may comprise text indicators <NUM> for gauging the level of aerosolisable material inside the reservoir <NUM>. It is envisaged that the text markings will depend on the application of the cartridge <NUM>. Accordingly, in some particular embodiments, the text indicators might comprise any of: a plurality of percentage amounts between <NUM>% - <NUM>%; plurality of fractions between/from zero and one; a plurality of volumetric amounts in imperial units; and or plurality of volumetric amounts in metric units (as shown in <FIG> with reference to the illustrated amounts V<NUM> ml. V<NUM> ml).

In accordance with some embodiments, the plurality of markings may be recessed into a surface of the cartridge <NUM>, or alternatively may project from a surface of the cartridge <NUM> (as shown in <FIG>). In some embodiments, the plurality of markings <NUM> may project from a surface of the reservoir <NUM>, and/or project into the reservoir <NUM>. In a particular embodiment, the plurality of markings <NUM> are located in a first wall portion <NUM> of the reservoir <NUM>, wherein the plurality of markings <NUM> project into the reservoir <NUM>.

The dimensions of the plurality of markings <NUM> may be varied depending on the application and size of the cartridge <NUM>. In accordance with some embodiments, the plurality of markings <NUM> may have a combined maximum dimension of no more than <NUM>, preferably no more than <NUM>, and more preferably no more than <NUM>. The phrase maximum dimension here means that the maximum length/width/thickness of the plurality of markings <NUM> must be more than the quoted amount in millimetres.

In terms of the orientation of the plurality of markings <NUM>, in accordance with some embodiments, the plurality of markings and/or the text indicators <NUM> may be orientated such that the cartridge <NUM> must be inverted/rotated from a first orientation in which the cartridge <NUM> is configured to operate when in normal use, to a second orientation (which is different from the first orientation) for allowing the user to gauge the level of aerosolisable material inside the reservoir against these plurality of markings/text indicators. Such an embodiment of cartridge is shown in the cartridge of <FIG>; and the cartridge shown in <FIG>, where the cartridge must be inverted from the first orientation to the second orientation (which is upside down from the upside first orientation) for allowing the user to gauge the level of aerosolisable material inside the reservoir against the text indicators <NUM>. As illustrated in the cartridge shown in <FIG>, the portion <NUM> of the cartridge <NUM> may be located on at least one side surface(s) 209C;209D of the cartridge <NUM>.

According to the invention, the side surfaces 209C;209D are inclined towards the outlet <NUM>. In <FIG>, and <FIG>, the portion <NUM> is located on two side surfaces 209C;209D which are each located between the first, front, surface 209A; and the second, rear, surface 209B opposite the front surface 209B of the cartridge <NUM>. The portion <NUM> of the cartridge in such embodiments as shown in <FIG> forms the first wall portion <NUM> and comprises a pair of windows <NUM>, such as one window <NUM> on each of the side surfaces 209C;209D, for viewing into the reservoir <NUM>.

In such embodiments, the portion <NUM>/each window <NUM> of the cartridge <NUM> may extend from a first position proximal the outlet <NUM> to a second position that is proximal the vaporiser <NUM>. In the embodiments shown in <FIG> and <FIG>, the plurality of markings <NUM> and the text indicators <NUM> are located on the first wall portion <NUM> of the reservoir <NUM>. By locating the portion <NUM> / window <NUM> proximal the outlet <NUM>, this allows the user to more easily observe residual levels of aerosolisable material inside the reservoir <NUM> when the cartridge <NUM> is orientated to have the outlet <NUM> facing downwards (see for instance an example residual level of aerosolisable material L<NUM> as illustrated in <FIG> and <FIG>, that is visible when such cartridges <NUM> are orientated to have the outlet <NUM> facing downwards, and when there is a residual level of aerosolisable material L<NUM> left in the reservoir <NUM>).

Returning to the cartridge shown in <FIG>, in accordance with some embodiments of cartridge <NUM>, the aerosolisable-material-level observation means <NUM> may comprise at least one light source <NUM> for illuminating the contents of the reservoir <NUM>. In some embodiments, the light source <NUM> may be located in the reservoir and/or attached to a wall of the reservoir <NUM>, as shown in <FIG>. The light source is preferably electrically powered, and in some embodiments is operable to receive power from a power supply <NUM> of the control unit <NUM> when the cartridge <NUM> is coupled to the control unit <NUM> (for instance via the contact electrodes <NUM>). Turning to the version of the cartridge <NUM> shown in <FIG>, in accordance with some embodiments of the cartridge <NUM>, an optical property of the portion <NUM> of the cartridge <NUM>, or the first wall portion <NUM>, may be operable to be varied by the user of the cartridge <NUM>. In that way, an aerosolisable-material-level observation means <NUM> may be provided for selectively allowing a user to observe the level of aerosolisable material <NUM> inside the reservoir <NUM> by varying the optical property of the portion <NUM>;<NUM> of the cartridge <NUM>. In accordance with some embodiments, the optical property of the portion of the cartridge <NUM> may be operable to be varied upon supply of an electric current to the portion of the cartridge <NUM> (for instance in some embodiments via the contact electrodes <NUM>), and/or varied in response to an electrical signal. In some embodiments, the optical property of the portion of the cartridge may be configured to be varied in response to the pressing of a button or switch <NUM>, which may in some particular embodiments be located on the cartridge <NUM>, as shown in <FIG>. Where an electrical supply is required for the aerosolisable-material-level observation means <NUM>, such as the embodiments outlined above, the aerosolisable-material-level observation means <NUM> may in such embodiments be operable to receive power from the power supply <NUM> of the control unit <NUM> when the cartridge <NUM> is coupled to the control unit <NUM> (for instance via the contact electrodes <NUM>).

The optical property which may be varied may, in some embodiments, be the translucency and/or the transparency of the portion <NUM>;<NUM> of the cartridge <NUM>. In that respect, in an example operation, the portion of the cartridge <NUM> may be varied/switched between a first state in which the user cannot observe the level of aerosolisable material <NUM> inside the reservoir <NUM>, and a second state (for instance a second state where the portion <NUM>;<NUM> is in a more transparent/translucent configuration than when the portion <NUM>;<NUM> is in the first state) where the user can observe the level of aerosolisable material <NUM> inside the reservoir <NUM>. A possible material for the portion <NUM>;<NUM> of the cartridge in such embodiments is an electrochromic material <NUM>, which might in some particular embodiments comprise an electrochromic glass; electrochromic plastic; and/or electrochromic ink. For such embodiments, <FIG> illustrates the portion <NUM>;<NUM> of the cartridge in the first state in which the user cannot observe the level of aerosolisable material <NUM> inside the reservoir <NUM>, whereas <FIG> illustrates the portion <NUM>;<NUM> of the cartridge in the second state in which the user can observe the level of aerosolisable material <NUM> inside the reservoir <NUM>.

Another modified version of the cartridge <NUM> in shown in <FIG>. As shown in these Figures, it is envisaged that in some embodiments of the cartridge <NUM>, the aerosolisable-material-level observation means <NUM> may comprise at least one contoured surface <NUM> located on a surface of the cartridge <NUM> (including for instance, but not necessarily limited to, any one or combination of the first, front, surface 209A; the second, rear, surface 209B opposite the front surface 209B; and/or the side surface(s) 209C;209D of the cartridge <NUM> which are located between the front surface 209A and the rear surface 209B). A function of the contoured surface <NUM>, which is a surface that is not featureless/smooth, is to improve the visibility of the aerosolisable material level <NUM> inside the reservoir due to the interaction of light with the contoured surface.

In accordance with some embodiments, such as the embodiment shown in <FIG>, a first contoured surface <NUM> may be located in the reservoir <NUM>. As shown in those Figures, the contoured surface is not smooth, and is not featureless, and may extend from the first end 31A of the reservoir <NUM> to the second end 31B, opposite the first end 31A, of the reservoir <NUM>. Depending on the embodiment, the first contoured surface <NUM> may, or may not, extend around the entirety of a circumference of the reservoir <NUM>. For instance, in some embodiments the first contoured surface <NUM> may extend around a half of a circumference of the reservoir <NUM>.

In some particular embodiments where the reservoir <NUM> comprises an elliptical cross section <NUM> comprising a major axis and a minor axis, the first contoured surface <NUM> located in the reservoir <NUM> may in such embodiments be located at one or both intersections of the elliptical cross section <NUM> with the major axis. Similarly, in some embodiments, the first contoured surface <NUM> may not be located at one or both intersections of the elliptical cross section <NUM> with the minor axis.

In accordance with some embodiments, a contoured surface <NUM> may be located on an outermost surface of the cartridge <NUM> (as shown in <FIG>). The presence of the contoured surface <NUM> on the outermost surface of the cartridge <NUM> not only provides a user with a gripping means for better holding the cartridge <NUM>, but also when the outermost surface is not opaque, improves the visibility of the aerosolisable material level <NUM> inside the reservoir <NUM> due to the interaction of light with the contoured surface <NUM>. As required, the contoured surface <NUM> may in some embodiments (as in the case of <FIG>), or may not in other embodiments, extend around the entirety of a circumference of the outermost surface of the cartridge <NUM>. In some embodiments, the contoured surface <NUM> may extend around a half of a circumference of the outermost surface of the cartridge <NUM>.

In terms of the shape/contours of each contoured surface <NUM>;<NUM>, one or more of the contoured surfaces <NUM>;<NUM> in accordance with some embodiments may comprise a plurality of surface features, such as grooves. In some embodiments, one or more of the contoured surfaces <NUM>;<NUM> may comprise a plurality of surface features in the form of projections and/or recesses <NUM>. As noted above, the surface features from these contoured surfaces <NUM>;<NUM> improve the visibility of the aerosolisable material level <NUM> inside the reservoir <NUM> due to the interaction of light with the contoured surface.

In relation to the contoured surfaces <NUM>;<NUM>, in some embodiments each such contoured surface <NUM>;<NUM> may be longer in a first (length) direction than in a second (width) direction that is perpendicular to the first direction. In some embodiments, the first direction of the contoured surface may be parallel to the longitudinal axis L of the cartridge <NUM>.

In accordance with some embodiments, the aerosolisable-material-level observation means may comprise a smooth surface <NUM> located on a surface of the cartridge <NUM>, such as a surface located in the reservoir <NUM> and/or a surface located on an outermost surface from the cartridge <NUM>. Where appropriate, these smooth surfaces may be polished. In some particular embodiments, the smooth surface <NUM> may be located on a first side of the reservoir <NUM>, with a contoured surface <NUM> located on a second side, opposite the first side, of the reservoir <NUM>. <FIG> illustrates such a particular embodiment of cartridge <NUM>. In that embodiment, the two opposing contoured/smooth surfaces <NUM>;<NUM> may further improve the visibility of the aerosolisable material level <NUM> inside the reservoir <NUM> due to the interaction of light with the two surfaces <NUM>;<NUM>. Furthermore, having only one or more of the sides of the reservoir that are contoured surfaces, as opposed to the entirety of the sides of the reservoir being contoured surfaces makes the cartridge <NUM> easier to tool and manufacture.

In some of the above embodiments, in terms of the materials used in the cartridge <NUM>, in some embodiments the first wall portion <NUM> and/or the second wall portion <NUM> may comprise/be made of plastic. In some embodiments, the first wall portion <NUM> may comprise/be made of a material that is different from the material of the second wall portion <NUM>. Such embodiments may be made using a two-shot moulding technique, where each of the different materials are one shot of the two-shot moulding technique. While this may increase the cost, manufacturing complexity, and/or material used, one can select an appropriate material for each portion of the cartridge, to form an appropriate aerosolisable-material-level observation means <NUM> with the desired characteristics. Alternatively, other embodiments may use the same material for the first wall portion <NUM> and second wall portion <NUM>. Such embodiments may be formed using a one-shot moulding technique.

In accordance with particular embodiments described above, the reservoir <NUM> and/or the aerosolisable-material-level observation means <NUM> may be made of plastic. The provision of plastic for these parts of the cartridge <NUM> makes the cartridge <NUM> lightweight and easy to manufacture.

Thus in accordance with certain embodiments of the disclosure, a cartridge for an aerosol provision system may generally comprise a housing part having a mouthpiece end and an interface end, wherein the mouthpiece end includes an aerosol outlet for the cartridge and the interface end includes an interface for coupling the cartridge to a control unit. An air channel wall (which may be formed by various components of the cartridge) extends from an air inlet for the cartridge to the aerosol outlet via an aerosol generation region in the vicinity of a vaporiser. The cartridge has a reservoir within the housing part containing aerosolisable material for aerosolisation. The reservoir is defined by a region within the housing part which is outside the air channel and an end of the reservoir at the interface end of the housing part is sealed by a resilient plug comprising a base part and an outer wall, wherein the outer wall of the resilient plug forms a seal with an inner surface of the housing part. Respective ends of a aerosolisable material transport element pass through opening in the air channel or into the reservoir so as to convey aerosolisable material from the reservoir to the vaporiser.

One aspect of some particular cartridge configurations in accordance with certain embodiments of the disclosure is the manner in which the resilient plug <NUM> provides a seal to the housing part <NUM>. In particular, in accordance with some example implementations the outer wall <NUM> of the resilient plug <NUM> which seals to the inner surface of the housing part <NUM> to form the end of the aerosolisable material reservoir extends in direction parallel to the longitudinal axis of the cartridge to a position which is further from the interface end of the cartridge than the aerosolisable material transport element / vaporiser. That is to say, the ends of the aerosolisable material transport element extends into the aerosolisable material reservoir in a region which is surrounded by the outer sealing wall of the resilient plug. Not only does this help seal the reservoir against leakage, it allows the geometry of the reservoir in the region which supplies the aerosolisable material transport element with aerosolisable material to be governed by the geometry of the resilient plug. For example, the radial thickness of the reservoir in this region can readily be made smaller than the radial thickness in other longitudinal positions along the air channel, which can help trap aerosolisable material in the vicinity of the aerosolisable material transport element, thereby helping to reduce the risk of dry out for different orientations of the cartridge during use.

The outer wall of the resilient plug may, for example, contact the inner surface of the housing part at locations over a distance of at least <NUM>, <NUM>, <NUM>, <NUM>, <NUM> and <NUM> in a direction extending from the interface end to the mouthpiece end (i.e. parallel to the longitudinal axis). The outer wall of the resilient plug may be in contact with the inner surface of the housing over the majority of this distance, or the outer wall of the resilient plug may include a number of (e.g. four) circumferential ridges <NUM> to help improve sealing. The resilient plug may be slightly oversized relative to the opening in the housing part so that it is biased into slight compression. For example, for the implementation shown in <FIG>, the interior width of the housing part into which the resilient plug is inserted in the plane of this figure is around <NUM>, whereas the corresponding width of the resilient plug is around <NUM>, thereby placing the resilient plug into compression when inserted into the housing part. As can be most readily seen in <FIG>, whereas the outer cross section of the cartridge housing part is symmetric under a <NUM>° rotation, the resilient plug <NUM> does not have the same symmetry because it includes a flat <NUM> on one side to accommodate the air channel gap <NUM> provided by the double-walled section <NUM> of the housing part (i.e. the resilient plug is asymmetric in a plane perpendicular to a longitudinal axis of the cartridge to accommodate the double-walled section of the housing part).

In terms of the radial size / width of the reservoir in the annular region where the aerosolisable material transport element extends into the reservoir, a distance between the air channel wall and the outer wall of the resilient plug in this region may, for example, be in the range <NUM> to <NUM>. In the example cartridge discussed above which has a generally oval housing part and a generally circular air channel, it will be appreciated the thickness of the reservoir is different at different locations around the air channel. In this example the aerosolisable material transport element is arranged to extend into the reservoir in the region where it is widest in the axial direction, i.e. into the "lobes" of the oval reservoir around the air channel. The portions of the aerosolisable material transport element that extend into the reservoir may, for example, have a length, as measured from the interior of the air channel wall, in the range <NUM> to <NUM>, e.g. in the range <NUM> to <NUM> or in the range <NUM> to <NUM>. The specific geometry in this regard (and for other aspects of the configuration) may be chosen having regard to a desired rate of aerosolisable material transport, for example having regard to the capillary strength of the aerosolisable material transport element and the viscosity of the aerosolisable material, and may be established for a given cartridge design through modelling or empirical testing.

Another aspect of some particular cartridge configurations in accordance with certain embodiments of the disclosure is the manner in which the air channel is routed through the cartridge, and in particular from the air inlet to the vicinity of the vaporiser (the aerosol generation region). In particular, whereas in a conventional cartridges an air inlet is typically provided at the interface end of the cartridge, in accordance with certain embodiments of the disclosure, an air inlet for the cartridge is located in a side wall of the housing part at a position which is further from the interface end than at least a part of the resilient plug that seals an end of the reservoir. Thus, the air channel in the cartridge is initially routed from the air inlet towards the interface end and bypasses the resilient plug before changing direction and entering the aerosol generation chamber through the resilient plug. This can allow the outer surface of the cartridge at the interface end, where it is closest to the vaporiser, to be closed, thereby helping to reduce the risk of leakage from the cartridge, both in terms of aerosolisable material coming through the openings in the air channel which is not retained by the aerosolisable material transport element in the air channel (e.g. due to saturation / agitation) or aerosolisable material that has being vaporised but condensed back to aerosolisable material in the air channel during use. In some implementations, a distance from air inlet to the interface end of the housing part may be at least <NUM>, <NUM>, <NUM>, <NUM>, <NUM> or <NUM>.

In some example implementations an absorbent element, for example a portion of sponge material or a series of channels forming a capillary trap, may be provided between the air inlet and the aerosol generation chamber, for example in the region air channel formed between the base of the resilient plug and the end cap, to further help reduce the risk of leakage by absorbing aerosolisable material that forms in the air channel and so helping prevent the aerosolisable material travelling around the air channel through the air inlet or towards the aerosol outlet.

In some example implementations the air channel from the air inlet to the aerosol outlet may have its smallest cross-sectional area where it passes through the hole <NUM> in the resilient plug. That is to say, the hole in the resilient plug may be primarily responsible for governing the overall resistance to draw for the electronic cigarette.

Another aspect of some particular cartridge configurations in accordance with certain embodiments of the disclosure is the manner in which the dividing wall element divides the air reservoir into two regions, namely a main region above the dividing wall (i.e. towards a mouthpiece end of the cartridge) and a aerosolisable-material-supply region below the dividing wall (i.e. on the same side of the dividing wall as where the aerosolisable material transport element extends from the vaporiser into the reservoir). The dividing wall includes openings to govern the flow of aerosolisable material on the main region to the aerosolisable material supply region. The dividing wall can help retain aerosolisable material in the aerosolisable material supply region of the reservoir, example when the electronic cigarette is tilted through various orientations, which can help avoid dry out. The dividing wall can also conveniently provide a mechanical stop for the resilient plug to abut / press against so as to help correctly locate the resilient plug during assembly and maintain the resilient plug in slight compression between the dividing wall and the end cap when the cartridge is assembled.

In the example discussed above, the dividing wall is formed as a separate element form the housing part, wherein an inner surface of the housing part includes one or more protrusions arranged to contact the side of the dividing wall facing the mouthpiece end of the cartridge to locate the dividing wall along a longitudinal axis of the cartridge, but in other examples the dividing wall may be integrally formed with the housing part.

In the example discussed above the dividing wall is in the form of an annular band around the air channel and comprises four fluid communication openings <NUM> located in respective quadrants of the band. However, more or fewer openings through the dividing wall may be provided in different implementations. Individual openings may, for example, have an area of between <NUM><NUM> and <NUM><NUM>.

A combined area for the at least one openings as a fraction of the total area of the dividing wall exposed to aerosolisable material supply region of the reservoir region may be, for example, from <NUM>% to <NUM>%; <NUM>% to <NUM>% or <NUM>% to <NUM>%.

It will be appreciated that while the above description has focused on some specific cartridge configurations comprising a number of different features, cartridges in accordance with other embodiments of the disclosure may not include all these features. For example, in some implementations an air path generally of the kind discussed above, i.e. with an air inlet which is in a sidewall of the cartridge and closer to the mouthpiece end of the cartridge than the vaporiser, may be provided in a cartridge which does not include a resilient plug with an outer sealing wall which extends around the vaporiser and / or does not include a dividing wall element of the kind discussed above. Similarly, a cartridge which does include a resilient plug with an outer sealing wall which extends around the vaporiser may have an air inlet into the cartridge which is at the interface end of the cartridge, and not in a sidewall, and which may also not have a dividing wall element of the kind discussed above. Furthermore, a cartridge which does include a dividing wall element, might not include an air inlet located further from the interface end of the cartridge than the vaporiser and / or an extended outer sealing wall for a resilient plug as discussed above.

Thus, there has been described a cartridge for an aerosol provision system comprising the cartridge and a control unit, wherein the system comprises a vaporiser for vaporising an aerosolisable material, wherein the cartridge comprises: an air channel extending from an air inlet for the cartridge to an outlet via an aerosol generation region; a reservoir for containing aerosolisable material for aerosolising; wherein the cartridge further comprises an aerosolisable-material-level observation means for allowing a user to observe a level of aerosolisable material inside the reservoir.

There has also been described a cartridge <NUM> for an aerosol provision system comprising the cartridge <NUM> and a control unit <NUM> is provided. The cartridge <NUM> comprises an air channel extending from an air inlet for the cartridge to an outlet via an aerosol generation region, and a reservoir <NUM> for containing aerosolisable material for aerosolising. The system comprises a vaporiser <NUM> for heating aerosolisable material from the reservoir <NUM> to generate aerosol in the aerosol generation region, and the cartridge comprises an aerosolisable-material-level observation means for allowing a user to observe a level of aerosolisable material inside the reservoir. The aerosolisable-material-level observation means may comprise at least one contoured surface <NUM> located on a surface of the cartridge <NUM>, such as a surface located in the reservoir <NUM>. The contoured surface <NUM> improves the visibility of the level of aerosolisable material <NUM> inside the reservoir due to the interaction of light with the contoured surface <NUM>.

Also described is a cartridge <NUM>;<NUM> for an aerosol provision system <NUM> comprising the cartridge <NUM>;<NUM> and a control unit <NUM>, wherein the system comprises a vaporiser for vaporising an aerosolisable material. The cartridge <NUM>;<NUM> comprises an air channel extending from an air inlet <NUM> for the cartridge <NUM>;<NUM> to an outlet <NUM> via an aerosol generation region, and a reservoir <NUM> for containing aerosolisable material <NUM> for aerosolising. The cartridge further comprises an aerosolisable-material-level observation means <NUM> for allowing a user to observe a level of aerosolisable material <NUM> inside the reservoir <NUM>. The aerosolisable-material-level observation means <NUM> may comprise at least one contoured surface <NUM> located on a surface <NUM>;<NUM> of the cartridge <NUM>;<NUM> to improve the visibility of the aerosolisable material level <NUM> inside the reservoir <NUM> due to the interaction of light with the contoured surface <NUM>.

Also described are the embodiments as set out in the clauses at the end of this specification.

While the above described embodiments have in some respects focussed on some specific example aerosol provision systems, it will be appreciated the same principles can be applied for aerosol provision systems using other technologies. That is to say, the specific manner in which various aspects of the aerosol provision system function, for example in terms of the underlying form of the vaporiser or vaporiser technology used are not directly relevant to the principles underlying the examples described herein.

In that respect, it will also be appreciated that various modifications may be made to the embodiments of aerosol provision system described herein. For instance, although the vaporiser <NUM> has been described in a number of the above embodiments as being located in the cartridge, it will be appreciated that in some embodiments the vaporiser may be located in the control unit of the aerosol provision system.

It will also be appreciated that the teachings herein, such as the aerosolisable-material-level observation means <NUM> (and any of its more specific features, such as the contoured surface <NUM>; the portion <NUM>; the window <NUM>; and/or the light source <NUM>), may also be applicable to other forms of aerosol provision system <NUM> which do not expressly comprise a cartridge <NUM>;<NUM> and a control unit <NUM>. From the foregoing therefore, also provided herein may be an aerosol provision system comprising a vaporiser for vaporising an aerosolisable material; an air channel extending from an air inlet for the aerosol provision system to an outlet via an aerosol generation region; a reservoir for containing an aerosolisable material for aerosolising; wherein the aerosol provision system further comprises an aerosolisable-material-level observation means for allowing a user to observe a level of aerosolisable material inside the reservoir. In accordance with such embodiments, it is envisaged that any of the features of the aerosolisable-material-level observation means <NUM>, such as it comprising a contoured surface <NUM>; the portion <NUM>; the window <NUM>, may form part of the aerosol provision system <NUM> itself, rather than as part of a cartridge <NUM>;<NUM> specifically.

Claim 1:
An aerosol provision system (<NUM>), wherein the system comprises:
a vaporiser (<NUM>) for vaporising an aerosolisable material;
an air channel extending from an air inlet to a mouthpiece outlet (<NUM>) via an aerosol generation region;
a reservoir (<NUM>) for containing aerosolisable material for aerosolising;
an aerosolisable-material-level observation means for allowing a user to observe a level of aerosolisable material inside the reservoir
wherein the aerosolisable-material-level observation means (<NUM>) comprises a portion (<NUM>) of the aerosol provision system (<NUM>), wherein the portion (<NUM>) forms a first wall portion (<NUM>) of the reservoir (<NUM>), and wherein the portion (<NUM>) further comprises:
a first window (<NUM>) for viewing into the reservoir, wherein the first window is inclined towards the mouthpiece outlet (<NUM>); and
a second window (<NUM>), wherein the second window (<NUM>) is inclined towards the mouthpiece outlet (<NUM>);
wherein the first window (<NUM>) is located on a first side of the reservoir, and wherein the second window (<NUM>) is located on a second side, opposite the first side, of the reservoir (<NUM>), wherein the first side and second side are inclined towards the outlet (<NUM>).