Patent Description:
Vapour provision systems, such as electronic cigarettes, generate an inhalable vapour or aerosol from one or more substrate materials which may be in liquid or gel form. Such materials are typically stored in a reservoir or tank, and delivered to a vapour generator such as an electrical heating element which is housed in a vapour chamber. A wall or partition separates the interior of the reservoir from the vapour chamber, and one or more openings or apertures are provided in the wall by which fluid can travel from the reservoir to the vapour generator, often by capillary action in a porous wicking element extending through the aperture.

Fluid flow through these apertures should be managed to deliver the fluid at an appropriate rate. Excess flow through an aperture can result in the presence of free liquid in the vapour chamber, from where it can move to other parts of the system, causing leaks, damage and poor quality aerosol.

<CIT> describes an electronic cigarette including an atomizer disposed within an atomizing chamber having an air inlet, an atomizer outlet and a first wick aperture. A liquid reservoir is sealably separated from the atomizing chamber. A wick is disposed through the first wick aperture between the liquid reservoir and the atomizing chamber to transfer liquid by capillarity from the liquid reservoir to the atomizer.

Approaches to inhibiting fluid leaks at reservoir apertures are therefore of interest.

To address the problems mentioned above, the invention proposes a component according to claim <NUM>. Further optional features are mentioned in the dependent claims <NUM>-<NUM>.

The approach described herein is not restricted to specific embodiments such as set out below, but includes and contemplates any appropriate combinations of features presented herein as long as they are covered by the scope of the claims.

Various embodiments of the invention will now be described in detail by way of example only with reference to the following drawings in which:.

As used herein, the terms "vapour provision device/system", "electronic vapour provision device/system", "aerosol provision device/system", "electronic aerosol provision device/system" and similar terms are intended to include non-combustible aerosol and vapour provision systems (non-combustible smoking articles) such as electronic smoking articles including electronic cigarettes or e-cigarettes that create vapour or aerosol from aerosolisable substrate materials by heating or other techniques such as vibration, heating devices that release compounds from substrate materials without burning such as tobacco heating products, and hybrid systems that generate aerosol from a combination of substrate materials, for example hybrid systems containing liquid or gel or solid substrates. The term "aerosol" may be used interchangeably with "vapour".

In some embodiments, the non-combustible aerosol or vapour provision system is a non-combustible smoking article such as an electronic cigarette, also known as a vaping device. The non-combustible aerosol provision system may comprise one or more components, such as a heater and an aerosolisable substrate. In some embodiments the system comprises a heater, a power supply capable of supplying power to the heater, an aerosolisable substrate such as a liquid or gel, a housing and optionally a mouthpiece. The aerosolisable substrate may be contained in a substrate container. The substrate container may be combined with or comprise the heater.

In some embodiments, the non-combustible aerosol or vapour provision system is a heating product which releases one or more compounds by heating, but not burning, a substrate material. The substrate material is an aerosolisable substrate material which may be, for example, tobacco or other non-tobacco products, which may or may not contain nicotine. In some embodiments, the product is a tobacco heating product. The tobacco heating product may comprise a heater, a power supply capable of supplying power to the heater, and an aerosolisable substrate such as a solid or gel material. The heating product may comprise an aerosolisable substrate such as a solid or gel material and a heat source which is capable of supplying heat energy to the aerosolisable substrate without any electronic means, such as by burning a combustion material, such as charcoal. The heating product may also comprise a filter capable of filtering the aerosol generated by heating the aerosolisable substrate.

In some embodiments, the non-combustible aerosol or vapour provision system is a hybrid system for generating aerosol by heating, but not burning, a combination of substrate materials. The substrate materials may comprise for example solid, liquid or gel which may or may not contain nicotine. In some embodiments, the hybrid system comprises a liquid or gel substrate and a solid substrate. The solid substrate may be, for example, tobacco or non-tobacco products, which may or may not contain nicotine. In some embodiments, the hybrid system comprises a liquid or gel substrate and tobacco.

The aerosol or vapour may be produced or released from a variety of substrates in various ways depending on the nature of the device, system or product. These include heating to cause evaporation, heating to release compounds, and vibration of a liquid or gel to create droplets. The substrate material, which may be one or more different materials within one system, may generally be referred to as an aerosol forming substrate, an aerosol forming substrate material, an aerosolisable substrate, an aerosolisable substrate material, or similar term. Substrate materials may be solid, liquid or gel, and may or may not comprise or include tobacco, and may or may not produce an aerosol or vapour containing nicotine. For example, the aerosolisable substrate material may comprise a vapour or aerosol generating agent or a humectant, such as glycerol, propylene glycol, triacetin or diethylene glycol.

Some embodiments of the disclosure are concerned with systems comprising two separable components that are connected together in use, namely a device component that may be reusable and a consumable component (such as a cartridge) that may be disposable or single use and which contains aerosolisable substrate material.

<FIG> shows a highly schematic and simplified diagram (not to scale) of an example aerosol/vapour provision or generation system such as an e-cigarette <NUM>. The e-cigarette <NUM> has a generally elongate shape comprising two main components, namely a control or power component, section or unit <NUM>, and a cartridge assembly or section <NUM>, that operates as an aerosol generating component. In this example, the components are arranged end-to-end, but other arrangements are possible, such as a side-by-side arrangement. Also, the overall shape of the system need not be elongate.

The control or power component <NUM> may be referred to as a "device", and is typically configured to be reusable (although this is not essential) to provide a plurality of aerosol provision experiences to a user over a period of days, weeks, months or years. The cartridge assembly <NUM>, which in some designs of system may be termed a "cartomiser", contains aerosolisable substrate material in the form of a liquid or gel, and is typically intended to be replaced when the substrate material has been used up, or consumed. Hence, this component <NUM> may be referred to as a "consumable component". In some examples, however, the consumable component may be configured to be refilled with substrate material when a first amount of substrate material has been consumed. The consumable component <NUM> may be intended to be replaced when other parts that may be contained within it reach an end of an operational lifetime, such as a heating element or a wicking component. In many examples, a single device will be able to be used with a plurality of consumable components which are replaced in sequence. In such a case, the operational lifetime of the device is intended to be longer than the operational lifetime of the consumable component. This is not essential, however, and the device may also be designed as a replaceable part, with a relatively short operational lifetime.

The consumable component <NUM> includes a supply of aerosolisable substrate material <NUM> in the form of a liquid or a gel which is stored in a reservoir or other storage volume. The substrate material is material from which an aerosol is to be generated, which may or may not be an aerosol containing nicotine. One or more flavourants may be included in the substrate. The consumable component <NUM> also comprises an atomiser (vaporiser) <NUM> operable to generate aerosol from the substrate material <NUM>. The nature of the atomiser <NUM> will be appropriate to the format of the substrate material <NUM>. Examples include an electrical heating element (operable by resistive heating or inductive heating) to which the substrate material is delivered by a wicking, capillary or other liquid transport arrangement for the liquid or gel to be vaporised, and a vibrating perforate sheet to which liquid or gel is delivered for droplet generation. A wide variety of vaporiser or atomiser configurations or assemblies able to generate vapour from aerosolisable substrate material delivered to the atomiser are known or will be readily apparent to the skilled person. In general, however, in the context of the present disclosure the atomiser <NUM> has the form of a chamber (vapour chamber) which houses a vapour generator or vapour generating element (such as the electrical heating element or the vibrating perforate sheet mentioned above) and is defined by a surrounding wall which separates the chamber from the reservoir holding the aerosolisable substrate material.

The consumable component <NUM> also includes a mouthpiece <NUM> having an opening or air outlet through which a user may inhale the aerosol generated by the atomiser <NUM>.

The device <NUM> provides power and control for generation of aerosol by the atomiser <NUM> from the aerosolisable substrate material <NUM>. Hence, the device <NUM> includes a cell or battery <NUM> (referred to herein after as a battery, and which may be re-chargeable) to provide power for electrical components of the e-cigarette <NUM>, such as the atomiser <NUM>. Additionally, there is a controller <NUM> such as a printed circuit board and/or other electronics or circuitry for generally controlling the e-cigarette. The controller <NUM> includes (or may be) a processor <NUM> (a microprocessor executing software, or electronics configured to perform the functions of a processor). The controller <NUM> connects the atomiser <NUM> to the battery <NUM> when vapour is required, for example in response to a signal from an air pressure sensor or air flow sensor (not shown) that detects an inhalation on the system <NUM> during which air enters through one or more air inlets <NUM> in a wall of the housing of the device <NUM> (or a wall of the consumable component <NUM> in other examples). When the atomiser <NUM> receives power from the battery <NUM>, the atomiser <NUM> operates to generate vapour from the aerosolisable substrate material <NUM>, and this forms an aerosol to be inhaled by a user through the opening in the mouthpiece <NUM>. The aerosol is carried from the atomiser <NUM> to the mouthpiece <NUM> along an air channel (not shown) that connects the air inlet <NUM> to the atomiser <NUM> to the air outlet when a user inhales on the mouthpiece <NUM>.

In the <FIG> example, the device <NUM> and the consumable component <NUM> are separate connectable sections detachable from one another by separation in a direction parallel to the longitudinal axis (in this example), as indicated by the solid arrow in <FIG>. The components <NUM>, <NUM> are joined or coupled together when the system <NUM> is in use by cooperating engagement elements <NUM>, <NUM> (for example, a screw or bayonet fitting) which provide mechanical and electrical connectivity between the device <NUM> and the consumable component <NUM>. This is merely an example arrangement, however, and the various elements may be differently distributed between the device <NUM> and the consumable component <NUM>, and other parts and elements may be included. The two sections may connect together for use end-to-end in a longitudinal configuration as in <FIG>, or in a different configuration such as a parallel, side-by-side arrangement. The system may or may not be generally cylindrical and/or have a generally longitudinal shape. Either or both sections or components <NUM>, <NUM> may be intended to be disposed of and replaced when exhausted (the reservoir is empty or the battery is flat, for example), or be intended for multiple uses enabled by actions such as refilling the reservoir and recharging the battery. In other examples, the system <NUM> may comprise its components within a single housing that provides the device functionality and the consumable component functionality in a single unitary system. A unitary system may be a disposable, single use system, or be configured for multiple uses by battery recharging or replacement and reservoir refilling. Embodiments and examples of the present disclosure are applicable to any of these configurations and other configurations of which the skilled person will be aware.

<FIG> shows a schematic cross-sectional view through a configuration of a vapour chamber. An atomiser <NUM> comprises a heating element <NUM> in the form of a heating coil, which is connectable to an electrical supply (not shown) for the provision of electrical power to generate heat by the Joule effect, and a wick element <NUM> around which the coil is wound. The wick <NUM> is a porous element able to absorb liquid and propagate liquid by capillary effects. The atomiser <NUM> is housed in a vapour chamber <NUM>, which has a boundary wall <NUM> defining the sides of the chamber <NUM>. A reservoir <NUM> surrounds the chamber <NUM>, and provides an annular storage volume defined between the boundary wall <NUM> and an outer wall <NUM> for holding source liquid or gel <NUM> (aerosolisable substrate material). The boundary wall has two opposing apertures <NUM> formed at opposite sides of the chamber <NUM>, through which the two ends of the wick <NUM> extend so as to reach into the storage volume of the reservoir <NUM>. In this way the wick <NUM> comes into contact with the liquid <NUM>.

The chamber <NUM> is open at its upper and lower ends (in the depicted orientation), and is comprised within an airflow path though a vapour provision system. The air flow path extends from one or more air inlets (such as inlet <NUM> in <FIG>) in the system's housing, through the chamber <NUM>, to an outlet in a mouthpiece (such as mouthpiece <NUM> in <FIG>). In use, the wick absorbs liquid <NUM> from the reservoir, and carries it to the vicinity of the heating element <NUM>. When the heating element is powered, it generates heat which vaporises the volatile liquid held in the wick <NUM> to produce a vapour in the vapour chamber. Air flow A along the air flow path passes through the chamber <NUM>, over the heater <NUM> and the wick <NUM> and gathers the vapour, some of which typically condenses to form an aerosol. The vapour and/or aerosol is carried by the air flow to the mouthpiece for inhalation by a user.

The <FIG> arrangement is merely exemplary; the various components may have different shapes, configurations and relative physical positions.

The form of the apertures <NUM> in the boundary wall <NUM> by which the wick <NUM> extends into the reservoir is of interest. The apertures <NUM> may be formed as simple holes drilled, punched or otherwise made in the boundary wall <NUM>. In other arrangements, the boundary wall <NUM> is formed from two or more shaped parts or components which abut one another with a space between the parts to provide an aperture. It is desirable to minimise leakage of liquid from the reservoir through the apertures, to avoid the presence of free liquid in the vapour chamber and therefore also in the air flow channel. Such free liquid can exit the system through the mouthpiece, or move against the air flow direction to leak from the system or come into contact with electrical components, causing damage. Some degree of sealing at the aperture/wick interface is therefore desirable. The seal should not be too tight or complete, though, since air must be able to enter the reservoir to balance pressure inside and outside the reservoir to maintain the flow of liquid to the atomiser. Also, a very tight seal might overly compress the wick and restrict liquid movement along the wick. Too loose a seal will enable free liquid leakage. Accordingly, the size and shape of the aperture relative to the wick passing through it is important, and should be selected with care to enable efficient liquid transport along the desired liquid flow path from reservoir to heating element, without excess liquid escaping into the chamber.

In designs where the boundary wall is formed from abutting adjacent parts, compliant or resilient materials such as rubber and silicon are popular for one or more of the parts. The compressible nature of these materials allow the required aperture to be formed when the parts are assembled together, with a degree of sealing around the wick to inhibit excess fluid from the reservoir escaping around the wick as a leak. However, the compressible nature also tends to mean that the formation of the aperture, and hence the fit of the aperture around the wick, can be inconsistent, both in terms of deviation from the intended design, and in variation between devices. In the assembled system, the aperture can potentially be too large or too small compared to the intended size. An large aperture can allow free liquid leakage into the chamber, and a small aperture can restrict liquid flow out of the reservoir, and restrict air flow into the reservoir which is necessary to replace consumed liquid to enable further outward liquid flow. Either of these conditions can reduce the amount of liquid available in the wick in the vicinity of the heating element, for vapour generation. A drier wick is susceptible to burning when exposed to the heat produced by the heating element, which is dangerous, and can contaminate the generated vapour.

Accordingly, the present disclosure proposes particular features for providing an aperture or apertures by which fluid is transported from a reservoir to a vapour generator. It is proposed that the boundary wall between the reservoir and the vapour chamber be formed from bodies made from rigid material (also "rigid bodies") which are abutted against one another, or made adjacent, and are shaped so that when abutted an aperture or apertures are defined between the abutted bodies.

<FIG> shows a simplified cross-sectional view through an example vapour chamber and reservoir arrangement. Many parts are as previously described with regard to <FIG>, and like reference numerals are used for like parts; the description of these parts will not be repeated in detail. As before, a boundary wall <NUM> is provided to separate the vapour chamber <NUM> from the reservoir <NUM>, where the vapour chamber <NUM> is centrally disposed within the annular reservoir <NUM>. Two apertures <NUM> extend through the boundary wall <NUM>, one on each side of the chamber <NUM> in an opposite disposition. Each aperture <NUM> provides a pathway for fluid flow or fluid transport of liquid from the interior of the reservoir <NUM> to the heating element <NUM> (the vapour generator being implemented as a heating coil in this example), where in this example the fluid flow is controlled and managed by a wick or wicking element <NUM> accommodated in the apertures <NUM>. A central portion of the wick <NUM> lies in the chamber and is encircled by the coils of the heating element <NUM>, and the two opposite end portions of the wick pass into and through the apertures <NUM> and extend into the reservoir <NUM>. The wick <NUM> is a porous element or member which is configured to absorb liquid from the reservoir <NUM> and transport that liquid by wicking or capillary action through pores in the wick <NUM> to the vicinity of the heating element <NUM>. As liquid at or near the heating element <NUM> is driven off as vapour, the wicking effect pulls new liquid through the porous network of the wick material towards the central portion so that a constant supply of liquid is available for vapour production. The wick may comprise any suitable porous material, selected for example with reference to its wicking capability as regards the particular qualities of the aerosolisable substrate material (liquid or gel) in the reservoir, such as viscosity. For example, the wick may comprise cotton, as a single strand, a plied yarn, or a bundle, twist or other grouping of strands or yarns. Other fibres may be used together with or instead of cotton, such as glass fibre or other natural fibres or man-made fibres. Other porous materials such as sponge materials and porous ceramics may also be used.

The boundary wall <NUM> is formed from two rigid bodies which are placed adjacent to each other in an abutting configuration. A first rigid body 28a defines the boundary wall <NUM> above the apertures <NUM> and a second rigid body 28b defines the boundary wall <NUM> below the apertures <NUM>. The rigid bodies 28a, 28b therefore each have a generally tubular or annular shape comprising a wall, partition or housing around a central void or cavity open at each end, so that when the rigid bodies 28a, 28b are abutted end-to-end by bringing facing end surfaces into contact, the central voids combine to form a continuous central void or space which is the vapour chamber <NUM> for the vapour provision system, and possibly also parts of the air flow channel upstream and downstream of the vapour chamber <NUM>. The edges of the rigid bodies 28a, 28b which are abutted are shaped such that when the edges are assembled together to build the boundary wall <NUM> and hence the chamber <NUM>, an open space is left between the edges which provides an aperture <NUM>. In this example, the rigid bodies 28a, 28b have a thickness, being a dimension generally orthogonal to the plane of the boundary wall <NUM>, and along the direction of the fluid transport path provided by the apertures <NUM>, sufficient to form apertures <NUM> which are elongate, in that their length (dimension along the fluid flow direction) is greater than their width (dimension orthogonal to the fluid flow direction). For example, the length may be two times the width, or more than two times the width. The apertures may be considered as being tubular, or having the form of hollow closed channels. This elongate nature can aid in reducing leakage of liquid through the apertures <NUM>, since the wick <NUM> is enclosed by the apertures <NUM> over a larger distance.

<FIG> shows a plan view of an example of the boundary wall <NUM> along the line IV-IV in <FIG>. The first or upper rigid body 28a and the second or lower rigid body 28b are both shaped on their abutting edges to define the opening for the aperture <NUM>, in which the wick <NUM> is accommodated. Each rigid body 28a, 28b has a semi-circular open channel or recess in the face of its abutting edge, which when brought together form a circular closed channel or tube, providing the aperture <NUM>. The two rigid bodies 28a, 28b therefore completely enclose the perimeter of the aperture <NUM>, and in this example, this enclosure is present over the whole length or elongate extent of the aperture, as can be appreciated from <FIG>.

The rigid bodies 28a, 28b are sealed or secured together at their abutting edges, rather than simply being placed in adjacent contact. This securing, along a join or joint <NUM> where the faces of the abutting edges come together, acts to maintain the shape and size of the aperture, thereby enhancing the consistency of the aperture dimensions, and seals the rigid bodies together to inhibit the passage of liquid other than through the apertures <NUM>. The securing may be achieved in any of a number of ways, where the selected technique may be chosen with regard to the nature of the material or materials used for the rigid bodies. For example, ultrasonic welding may be used to fuse the materials of the abutting bodies together once they are assembled. Adhesive may be applied to one or both abutting faces before the rigid bodies are assembled together, so that the securing is achieved by gluing. The securing is applied along the full extent of the abutted faces, so as to provide a liquid-tight seal between two adjacent rigid bodies, so that liquid can only travel out of the reservoir via the apertures.

The apertures may have any cross-sectional shape, and are not limited to the circular shape shown in the example of <FIG>. The rigid material of the rigid bodies combined with the secure leak-proof joining of the rigid bodies provides a consistent and stable aperture size and aperture location, so that liquid flow out of the reservoir can be accurately regulated. The flow of liquid to the heating element is regulated during use of the system for vapour provision, and the aperture properties inhibit leakage when the system is inactive. The aperture size, shape and location are not affected by the assembly process, again owing to the rigid nature of the material used to form the boundary wall, so that product-to-product consistency is enhanced.

<FIG> shows a further example in plan view along the line IV-IV of <FIG>. In this example, the first rigid body 28a has no shaping on its abutting edge at the joint <NUM>, whereas the second rigid body 28b has a semi-circular open channel as in the <FIG> example. Hence, when the rigid bodies 28a and 28b are assembled together, the flat surface of the first rigid body overlies and closes the open channel on the second rigid body, to form a closed channel or tube of semi-circular cross-section, this being the aperture <NUM>. The wick <NUM> may be of a similar cross-sectional shape, or may be compressed from some other shape, such as circular, in order to be accommodated within the aperture <NUM>.

<FIG> shows a still further example in plan view along the line IV-IV of <FIG>. In this example, three rigid bodies 28a, 28b and 28c are brought together to form the boundary wall <NUM>. The aperture <NUM> is formed at the junction between the three rigid bodies 28a, 28b, 28c, each of which has shaping on its abutting edge face to define a circular cross-section aperture <NUM> when the bodies are assembled together and secured along the joints <NUM>. Other configurations of multiple rigid bodies might also be used, such as separate rigid bodies for opposite sides of the boundary wall, where some joints between the rigid bodies would be separated from the aperture locations, so the relevant edge surfaces would not include shaping to define an aperture.

The rigid bodies may be made from any suitable rigid material. By "rigid", it is meant that the material lacks pliancy, elasticity or deformability to any discernible extent in use; when the rigid bodies are assembled together they form a solid structure that maintains its volume and shape and is not deformable or compressible under regular conditions of use of the vapour provision system. In this way, the shape, size and position of the aperture is maintained. Suitable materials includes plastics, such as polybutylene terephthalate (PBT), thermoplastics, and reinforced plastics and thermoplastics, for example reinforced with glass fibre. An example is Grivory (RTM) HT1V-<NUM> FWA, a <NUM>% glass fibre reinforced thermoplastic based on a semi-crystalline, partially aromatic copolyamide which is made by EMS-Grivory, and has good performance at high temperature as regards stiffness, strength, distortion stability and chemical resistance, which are all valuable properties in the environment of a vapour chamber. Examples of plastics include PEEK (polyether ether ketone), polypropylene, and copolyesters which have good strength and mechanical properties that are retained even under chemical exposure; an example is Tritan (RTM) made by Eastman Chemical Company. Other materials include metals and glass materials. Laser welding may be used to secure the rigid bodies in the case of metals and glasses. Further examples of suitable rigid materials are non-porous ceramics. All rigid bodies forming the boundary wall may be formed from the same rigid material. Alternatively, different rigid bodies may be formed from different materials. This could be useful having regard to different relationships between the rigid bodies and other components of the vapour provision system, for example.

Any number of rigid bodies can be used to form the boundary wall, although two bodies, one defining one side of the aperture's perimeter and one defining the other side of the aperture's perimeter, require the least amount of assembly work. The aperture can have any cross-sectional shape, and indeed may have a cross-sectional shape and/or area that varies along the length of the aperture.

For ease of assembly, the relevant portion of the wick can be placed into the shaping on one of the rigid bodies that will define the aperture before the rigid bodies are brought together for securing. Hence, when the rigid bodies are assembled together, the wick is already installed in the aperture. This is convenient if the wick has a same or similar cross-sectional size to the aperture, or if the wick has a larger cross-section so that it is compressed when accommodated in the aperture. Alternatively, the end of the wick can be inserted into or threaded through the aperture after the boundary wall has been formed by securing the rigid bodies together.

In the examples discussed thus far, the apertures are arranged as an oppositely disposed pair across the vapour chamber, and have a straight configuration, in that the longitudinal axis of each tubular aperture is linear, and also substantially perpendicular to the plane of the boundary wall. Accordingly, the wick is held in a linear configuration, with its longitudinal axis arranged substantially along a straight line. This line is orthogonal to the direction of airflow through the vaporisation chamber. The wick may be made of a material of sufficient stiffness that it has this linear shape in its own right, or if the wick material is less rigid, the wick can be held straight by its insertion in the straight format of the pair of apertures.

However, the disclosure is not limited in this regard. The apertures may alternatively have a shape which is non-linear. In other words, the longitudinal axis of an aperture may not lie along a straight line; the aperture may be curved, including one or more bends.

<FIG> shows a simplified cross-sectional view of a further example of a vapour chamber, with like parts again labelled with the same reference numerals. In this example, the boundary wall <NUM> between the reservoir <NUM> and the vapour chamber <NUM> is formed from an upper rigid body 28a and a lower rigid body 28b. The rigid bodies 28a, 28b are shaped on their abutting surfaces such that when they are assembled together, an aperture <NUM> is formed which has a curved or bent shape. A similar aperture <NUM> is provided on each side of the chamber <NUM> so that a single wick <NUM> can be accommodated across the chamber <NUM> with each end portion in the reservoir and the central portion with the heating element <NUM> disposed in the chamber perpendicular to the air flow direction, as before. In the depicted orientation, each aperture <NUM> has a curved tubular shape with an opening (cross-section) at the aperture end leading into the chamber <NUM> which lies in the plane of the boundary wall <NUM>, and an opening (cross-section) at the opposite aperture end leading into the reservoir <NUM> which lies in a perpendicular plane. The aperture <NUM> has a bend in its central portion which is substantially a right angle, so that its two ends are perpendicular as noted. In this example, the lower rigid body 28b extends outwardly below the level of the wick to define a base wall 3a of the reservoir <NUM> before turning vertically upwards to define an outer wall for the annular reservoir <NUM>. This provides a simple structure, but these various parts may alternatively be formed from various separate components instead.

<FIG> shows a longitudinal cross-sectional view of the curved aperture <NUM> of <FIG>. As described, the aperture <NUM> is defined between the abutted, opposing edge surfaces of an upper or first rigid body 28a and a lower or second rigid body 28b. The aperture <NUM>, being elongate, has a tubular configuration, with a longitudinal axis L. A first portion of the length or longitudinal extent of the aperture <NUM> connects with the chamber <NUM>, and a second portion of the length or longitudinal extent of the aperture <NUM> connects with the reservoir <NUM>. The first portion has a longitudinal axis L1 and the second portion has a longitudinal axis L2, and in this example the two longitudinal axes lie an angle θ to one another of substantially <NUM> degrees, since the aperture <NUM> has a right-angled bend or turn in it. However, the feature is not limited to a right angle. An aperture with a bend may comprise an angle θ between the axes of first and second portions which is less than <NUM> degrees. If the right-angled arrangement is generally preferred, the angle might lie in the range of <NUM> to <NUM> degrees, for example, or in the range of <NUM> to <NUM> degrees. In the <FIG> example, the two oppositely disposed apertures have the same shape and curvature, but this is optional; two apertures for accommodating two ends of the same wick might have different bend angles (angles of curvature) and/or different bend directions, or one aperture may be curved and the other aperture may be straight as in the <FIG> example. Also, an aperture may comprise more than one curve or bend along its longitudinal extent.

The curved or bent shape of the aperture accommodates a wick in a similarly curved or bent orientation. The wick may be formed into such a shape in advance if it is made from a relatively stiff material, or may be given the curved shape by virtue of its fit within the curved aperture.

The curved or bent aperture may assist in protecting against leakage from the reservoir via the aperture, since the liquid flow path is made more tortuous and less direct. Also, the same length of wick may be accommodated within a narrower widthways extent across the system, so the external dimensions of the system can be smaller if desired. Also, if the curvature is towards the base of the reservoir, as in <FIG>, the wick ends can reach closer to the base wall 3a of the reservoir <NUM> for better absorption of all liquid from the reservoir, while the heating element <NUM> can still be positioned centrally in the vapour chamber <NUM>. Hence, there are a number of features offered by an arched wick shape, enabled by an arched or curved aperture arrangement, which can be attractive in various circumstances.

An atomiser in a vapour provision system need not comprise a wick or similar porous element for transporting liquid from a reservoir to a vapour generator such as the heating coil of the preceding examples. Capillary action to draw liquid out of the reservoir and deliver it into the vapour chamber for vaporisation can be achieved by one or more capillary channels, being slots, channels, openings and the like which are dimensioned on a sufficiently small scale that the capillary effect takes place. Accordingly, the boundary wall apertures described herein may not be configured to accommodate a wicking element, but may instead have a smaller cross-sectional area of a size to produce capillary action. Such apertures may be curved or straight, as described. The operation of such capillary apertures can be enhanced by the use of the described rigid bodies. The improved consistency of aperture shape, size and location which is enabled by the rigid materials is valuable in the context of forming small channels, since tolerance to manufacturing errors is less for smaller-scale features.

In the examples discussed thus far, the perimeter of the or each aperture has been wholly defined and enclosed by the rigid material of abutting and secured rigid bodies at all points along the length of the aperture. The term "perimeter" is intended to describe the closed path or line of the side wall enclosing the aperture, where the side wall surrounds and defines the bore of the aperture since the aperture has a tubular shape. The perimeter is the boundary of the transverse cross-section of the aperture, in the plane perpendicular to the longitudinal axis. In other examples, the rigid material may enclose the full extent of the perimeter for only a part or portion of the length of the aperture. In another part or portion, an additional component, of a non-rigid material, may define part of the perimeter. This component may be, for example, an element such as a gasket formed from resilient material and placed between the rigid bodies in the vicinity of the aperture.

<FIG> shows a simplified cross-sectional view of an example vapour chamber that includes a gasket. The component is configured in substantially the same way as that of the <FIG> example with, additionally, a gasket <NUM> included. The gasket <NUM> is placed against the abutting surface of the upper rigid body 28a across the area which defines the aperture <NUM>, and extending beyond the width of the aperture. As shown, the gasket <NUM> sits in a recess <NUM> formed in the abutting surface of the upper rigid body 28a, so as not to protrude into the volume intended for the aperture. The lower rigid body 28b is abutted against the upper rigid body 28a as before, and contacts the gasket <NUM> in the border region around the aperture <NUM>, and the upper rigid body itself elsewhere.

<FIG> shows a plan view of the boundary wall <NUM> along the line VII-VII in <FIG>, from which the arrangement of the gasket <NUM> may also be appreciated. The gasket <NUM> fills a recess in the abutting surface of the upper rigid body 28a, where the recess is wider than a channel in the abutting surface of the lower rigid body 28b which defines the aperture <NUM>. Thus, the joint <NUM> is between the rigid bodies 28a, 28b directly at locations remote from the aperture <NUM>, and may be secured by ultrasonic welding or gluing as before, whereas the joint is between the lower rigid body 28b and the gasket <NUM> immediately adjacent to the aperture <NUM>. The gasket <NUM> extends across the width of the aperture <NUM>. Hence, the perimeter of the aperture <NUM> is defined partly by the gasket and partly by the rigid material at the location of the opening of the aperture <NUM> into the chamber <NUM>, and also over a first longitudinal portion of the aperture, according to the inward extent of the gasket shown in <FIG>. Beyond this, the perimeter of the aperture <NUM> is wholly defined by the rigid material of the rigid bodies, as can be seen in <FIG>. In an alternative, the gasket or other resilient element may be positioned so as define part of the aperture perimeter at some longitudinal position along the aperture length which is separated from the end of the aperture that opens into the vapour chamber.

The securing of the rigid bodies to one another to effect sealing can be carried out over those areas where the material of the rigid bodies is in contact at the joints between two rigid bodies. Where the gasket contacts the opposite rigid body around the aperture, sealing is provided by the resilient nature of the gasket material. The gasket may be formed from silicone, for example. Other suitable materials for the gasket include thermoplastic elastomers (TPEs) and thermoplastic polyurethane (TPU), but other resilient materials are not excluded. The presence of silicone or a similar resilient, compressible material, around a portion of the aperture's perimeter can assist in sealing around the wick <NUM> as it sits in the aperture.

As an alternative, the gasket may extend further or much further beyond the width of the aperture. Indeed, the gasket may extend so far as to be ring-shaped (circular or non-circular) and disposed between the upper and lower rigid bodies so that it completely encircles or circumscribes the vapour chamber. In such a case, the joint between the upper and lower rigid bodies can be completely filled with the gasket material all around the inner surface of the boundary wall. The gasket material can act to provide a liquid-tight seal between the rigid bodies, so that bonding such as by ultrasonic welding or gluing is not necessary. The gasket material provides the effect of securing of the rigid bodies to each other, in that it seals the rigid bodies together and achieves the same results as welding, gluing and the like. Beyond the outward extent of the gasket (in other words, outside the ring), the rigid bodies are in contact as before, providing the stability to achieve a consistent aperture size, shape and position. To enhance the sealing effect of the gasket, and to place and hold it in the correct position, it may be formed with protrusions and/or recesses which engage with corresponding recesses and/or protrusions in the rigid bodies.

<FIG> shows a sectional view through a vapour chamber configured similarly to the <FIG> example, viewed from the line VIII-VIII and looking towards the aperture <NUM>. The wick and the heating element are removed for clarity. The gasket <NUM> is in the form of a ring, extending around the whole perimeter of the vapour chamber <NUM>, and sandwiched between the top of the lower rigid body 28b and the base of the upper rigid body 28a so that an inward facing surface of the ring forms part of the boundary wall <NUM> and creates a seal between the two rigid bodies 28a, 28b. The upper surface and lower surface of the gasket <NUM> have protruding features <NUM> formed on them; these features may be continuous or discrete around the ring-shape. The facing surfaces of the upper and lower rigid bodies 28a, 28b, which would abut in the absence of the gasket <NUM>, are provided with recesses <NUM> which match the shape of the protrusions <NUM> on the gasket and receive the protrusions when the boundary wall is assembled, so that the three parts engage together. The protrusions <NUM> and recesses <NUM> may be reversed, and/or differently shaped and positioned.

Shaped engaging, latching or clipping cooperating surface features may also be provided between the rigid bodies to assist with securing them together and reinforcing the sealing effect of the gasket by holding it more securely or tightly in position, including possible compression of the gasket. Such an arrangement might be used as an alternative to welding or gluing. The rigid bodies could then be assembled by simply pushing them together to achieve a "snap fit" or clipping action between the cooperating features. If a very tight abutment can be achieved by this approach, it may be possible to rely only on the engagement of such cooperating features to seal the bodies together, with no need for welding, gluing or a gasket.

The gasket can be assembled with the bodies by placing it into a recess on a facing surface of one or other rigid body shaped to receive it, or simply overlying it on a facing surface, and then bringing the other rigid body into the abutting position.

<FIG> shows an external perspective view of an example upper rigid body and gasket, prior to assembly. The upper body 28a has a detailed moulded external shape with features intended for cooperation with other components of the vapour provision system. Overall, it has a generally annular shape, with a central through-cavity open at the top and bottom to define part of the vapour chamber <NUM>. The gasket <NUM> is ring-shaped, with a central opening corresponding to the boundary wall of the vapour chamber <NUM> defined by the upper rigid body 28a. The gasket <NUM> has an upwardly protruding contiguous rim <NUM>, being a surface feature for engagement into a corresponding recess in the upper rigid body 28a when the gasket is pressed up into the upper rigid body, as shown in <FIG>.

<FIG> shows an external perspective view of another example upper rigid body and gasket, prior to assembly. The upper body 28a has the same exterior form as the <FIG> example. The gasket <NUM> also has the same form as the <FIG> example, except for the addition of two legs <NUM>, which provide the function of pull-tabs. The legs <NUM> are provided on opposite sides of the upper surface of the gasket <NUM>, towards the location of the upper rigid body 28a, and each has the form of a long, thin substantially straight extending part, having a length greater than the depth of the upper rigid body 28a along the same direction. The upper rigid body has two narrow through-holes (not visible) along this same direction which are aligned with the position of the legs <NUM>. To assemble, the legs <NUM> are pushed or pulled through the through-holes, and the ends of the legs <NUM> can be grasped and used to pull the gasket <NUM> fully into its intended position against the facing surface of the upper rigid body 28a. The legs <NUM> will then protrude significantly above the upper rigid body, and their upper portions are effectively waste material and can be cut off or torn away. The gasket <NUM> and the legs <NUM> can be moulded from silicone or other resilient material as a unitary part. One leg <NUM> or more than two legs <NUM> may be provided, in alternatives.

In order to engage the gasket <NUM> tightly against the upper rigid body 28a, each leg <NUM> may include a widened portion <NUM> at a position that lies just beyond the remote end of the corresponding through-hole when the gasket <NUM> is assembled into the upper rigid body 28a. The widened portion <NUM> has a greater width than through-hole, but the compressible nature of the resilient material from which the gasket <NUM> is made allows the widened portion to be squashed into a reduced volume so it can be pulled through the through-hole, following the narrower part of the leg <NUM>. Once the widened portion <NUM> exits the remote end of the through hole, it expands to its original width, wider than the through hole, and hence "locks" the leg in place by inhibiting movement in the reverse direction back into the through hole. In this way, the gasket is also locked in place and kept held against the facing surface of the upper rigid body in its intended position. The surplus leg material is then removed above the widened portion <NUM>.

<FIG> shows a simplified cross-sectional view of the gasket <NUM> installed in position with the upper rigid body 28a, with a leg <NUM> inserted through the through hole <NUM> in the upper rigid body 28a until the widened portion <NUM> has emerged from the remote end of the through hole <NUM> and resumed its proper width in excess of the width of the through hole <NUM>. The gasket <NUM> is in contact with the upper rigid body 28a as required. The upper portion 42a of the leg <NUM>, above the widened portion <NUM>, can be removed.

<FIG> shows an external perspective view of another example upper rigid body and gasket, prior to assembly. The upper body 28a has the same exterior form as the <FIG> example. The gasket <NUM> also has the same form as the <FIG> example, except for the inclusion of a central portion 36a which fills the central void intended to be occupied by the vapour chamber in the assembled system. The gasket <NUM> thus has a planar shape rather than the intended ring shape, and may be considered as a precursor gasket that will be used to provide the final intended ring-shaped gasket. The solid planar shape increases the surface area of the gasket <NUM>, and also increases its stiffness / decreases its flexibility. These properties may make the gasket <NUM> easier to insert into the upper rigid body 28a when assembling the boundary wall. Once the gasket is in position, and possibly also the lower rigid body has been added, the central portion 36a of the gasket <NUM> is removed by being cut, cropped or punched away from the surrounding ring of gasket material.

In a further alternative, if at least one of the rigid bodies is formed from a material suitable for moulding, the gasket can be assembled with that rigid body in a two shot (or two step or two stage) injection moulding process. Two shot moulding enables a single complex shaped item to be moulded from two different materials, typically polymers. For the present case, a rigid body can be moulded from a first material in a first shot of the process, to create the required shape including any recess for accommodating the gasket. Then, a second material for the gasket is added in a second shot of the process, to be formed by the moulding directly onto the already-formed rigid body at the appropriate location. For appropriately compatible materials, this can create a strong bond between the rigid body and the gasket, which is formed as the gasket material solidifies. Hence there is no possibility of leakage between the rigid body and the gasket. Other benefits of this approach include a high consistency of quality between components, since every gasket-rigid body combination will be formed in the same mould and will essentially be identical, and manufacturing times can be brief since two-shot moulding can be a rapid process. The gasket is hence securely and accurately positioned with respect to the rigid body. The further rigid body or bodies, plus a wick if included, can then be assembled onto the combined moulded item to make the completed boundary wall component.

The examples described in detail above have all utilised an electrical heating element in the form of a wire coil. However, the disclosure is not limited in this regard. Other electrical heating elements may be used, including other wire shapes, planar metal shapes for example cut from sheet metal, traces of metal or other conductive material printed or deposited onto a substrate (which may be a wicking element), or elements formed from other conductive materials, such as ceramics. An electrical heating element may be configured to heat by induction or by resistive current flow. A vapour generator operable by means other than heating may alternatively be used, such as a vibrating perforated plate able to create liquid droplets. In any arrangement, the vapour generator may receive the aerosolisable substrate material from the reservoir via the aperture or apertures with or without a wick or similar porous element.

<FIG> introduced the concept of a non-linear aperture, able to accommodate a wick having a bent or curved shape, such as an arch. As discussed, there are a number of attractive features associated with this arrangement. At least some of these can be achieved without the requirement for forming the boundary wall from rigid bodies. Such an embodiment is however not part of the claimed invention. Accordingly, the present disclosure is also directed to the general concept of a fluid flow aperture through a boundary wall from a reservoir to a vapour chamber where the aperture has a longitudinal axis which does not lie along a straight line. The various features of curved apertures discussed above with regard to <FIG> are applicable to this not claimed concept, without any particular requirements for the boundary wall in which the aperture is defined. The boundary wall need not be made from rigid material, or may be made from rigid material in part only. It may or may not comprise rigid bodies secured or sealed together.

Claim 1:
A component for a vapour provision system (<NUM>) comprising:
a boundary wall (<NUM>) separating a reservoir (<NUM>) for holding a fluid from a chamber (<NUM>) for housing a vapour generator (<NUM>), the boundary wall comprising two or more adjacent rigid bodies (28a, 28b) abutted against one another at edges of the adjacent rigid bodies, and sealed to one another at the abutting edges; and
an elongate tubular aperture (<NUM>), with a length greater than a width, in the boundary wall providing a fluid transport path from the reservoir to the vapour generator, wherein the length of the tubular aperture is a dimension along a fluid flow direction and a width of the tubular aperture is a dimension orthogonal to the fluid flow direction;
wherein the aperture is defined between the abutted adjacent rigid bodies, one or more of the adjacent rigid bodies being shaped on their abutting edges to define an opening for the aperture, and the rigid bodies enclosing a perimeter of the aperture along at least part of aperture's length.