Patent Description:
Any discussion of prior art throughout the specification should in no way be considered an admission that such prior art is widely known or forms part of the common general knowledge in the field.

<CIT> describes a mixing unit comprising a sealed container joined to a second container.

<CIT> describes a refill container that can facilitate refilling work.

Liquid cleaning and hygiene products, such as multi-purpose surface cleaner, glass cleaner, or degreaser, are often supplied in ready-to-use concentrations in a wide variety of containers, with a wide variety of dispensing systems. Typically, such liquid cleaning products comprise one or more active ingredients diluted with water (or another solvent) to a concentration that is suitable for use in the home or commercial environment.

Cleaning products supplied in a ready-to-use concentration are advantageous in that the products can be supplied in a safe and effective concentration, and can be appropriately labelled. Ready-to-use products are also more convenient for the user, since they do not require dilution or reconstitution before use.

One example of a widely used container system for cleaning products is a spray bottle comprising a trigger actuator. Such systems generally comprise a bottle comprising a body and a neck, the neck being configured to engage a removable spray nozzle. The spray nozzle is generally secured to the neck of the bottle by way of complementary screw threads on the neck and on the nozzle. After use, the container or vessel in which the cleaning product was supplied is typically discarded and a replacement acquired.

Although the spray bottle in which cleaning products are supplied generally have a lifetime that extends beyond the point at which the cleaning product has been depleted, the practice of refilling spray bottles with cleaning product is not widespread in a domestic setti ng.

In a commercial or industrial setting, spray bottles are sometimes refilled for re-use by diluting a predetermined volume of concentrated liquid with water. The concentrated cleaning liquid may be supplied in a bottle, which typically has a larger volume than the spray bottles used by cleaning professionals due to the fact that the concentrate vessel is not carried throughout the cleaning process.

However, although it is known to supply concentrated cleaning fluids for dilution prior to use, the practice of refilling spray bottles with water and a concentrated cleaning fluid is not widespread due to the many challenges in safely and effectively managing concentrated products, especially in a home environment.

Handling of concentrated cleaning fluids requires care both during refilling of a spray vessel and with regard to storage of the concentrated liquid. To avoid risks to health, even more so than diluted cleaning fluids, concentrated cleaning fluids should be transported and stored securely, and kept out of reach of children and animals.

Moreover, concentrated (undiluted) cleaning fluids may cause damage to surfaces within the home, and, thus, spillages should be avoided to avoid damage to clothing and household items.

Further difficulties may be encountered in ensuring that the concentrated cleaning product is diluted to a safe and effective concentration. Over-dilution of a concentrated cleaning fluid with water may lead to inferior cleaning results. Under-dilution of a concentrated cleaning fluid may present a risk to health, damage to household items and excessive consumption of the concentrated cleaning fluid.

Despite a desire to reduce the plastic waste generated by discarding empty bottles, and a desire to reduce the costs and resources required to ship and store ready-to-use cleaning products, refill systems that are suitable and convenient for use in domestic and professional settings are not widely available.

The present inventors have been able to solve many of the problems associated with conventional cleaning product dispensing systems and have been able to develop a refill capsule system for use with spray bottles (and other cleaning product vessels) that can overcome many of the above problems.

An object of the present invention is to provide a refill capsule and an associated cap assembly that overcome the above mentioned disadvantages associated with current cleaning products that allows vessels or containers for cleaning products to be reused.

It is another object of the invention to provide a refill system comprising a cap assembly that allows a user to safely and reliably deliver a predetermined volume of concentrated cleaning fluid to a spray bottle or similar vessel for dilution.

It is another object of the invention to provide a refill capsule and an associated cap assembly that allows for safe and reliable delivery of a concentrated cleaning fluid to a refillable vessel.

It is yet another object of the invention to provide a refill capsule and an associated cap assembly that can be simply and reliably coupled to a refillable vessel to discharge the concentrated liquid into the refillable vessel.

These and other objects are accomplished by the invention described in the following text and figures.

In a first aspect of the present invention, there is provided a cap system comprising a cap assembly having a frangible seal and a plug configured to break the frangible seal. The cap assembly according to the invention is described in the claims apended herewith. Optional features are described in the dependent claims.

The cap system according to the invention allows a volume concentrated cleaning fluid to be safely and conveniently stored and transported. The system can be engaged, for example by virtue of a threaded engagement, with a refillable vessel. Upon engagement of the system with a refillable vessel, the frangible seal is configured to break, thereby releasing the concentrated cleaning fluid contained in a capsule to flow into the refillable vessel.

In the following, it should be note that the term 'comprising' encompasses the terms 'consisting essentially of' and 'consisting of'. Where the term 'comprising' is used, the listed steps or options need not be exhaustive and further steps or features may be included. As used herein, the indefinite article 'a' or 'an' and its corresponding definite article 'the' means at least one, or one or more, unless specified otherwise.

The terms 'upstream' and 'downstream' as used herein refer to the direction of flow of fluid through the refill system during use, with fluid flowing from an upstream end to a downstream end. In the context of the present invention, fluid flows from an upstream refill capsule system into a downstream refillable vessel. The proximal direction is the upstream direction, whilst the distal direction is the downstream direction.

In specifying any range of values or amounts, any particular upper value or amount can be associated with any particular lower value or amount.

The various features of the present invention referred to in individual sections above apply, as appropriate, to other sections mutatis mutandis. Consequently features specified in one section may be combined with features specified in other sections as appropriate. Any section headings are added for convenience only, and are not intended to limit the disclosure in any way.

The invention is not limited to the examples illustrated in the drawings. Accordingly it should be understood that where features mentioned in the claims are followed by reference numerals, such numerals are included solely for the purpose of enhancing the intelligibility of the claims and are in no way limiting to the scope of the claims.

The present invention relates to a cap system for a refill capsule. The cap system comprises a cap assembly configured to close a capsule body and a plug configured to break a frangible seal provided in the cap assembly when the capsule body is engaged (threadedly engaged, push fit, etc.) onto a refillable vessel. The frangible seal is provided by a frangible connection between the closure member and the conduit. The frangible connection extends in a first plane, which is orthogonal to a longitudinal axis A of the conduit.

As used herein, the term 'refill capsule' refers to a capsule body for containing a fluid, such as concentrated cleaning product.

The plug is disposed within the cap assembly and is configured to move from a first position to a second position as the system is engaged with a refillable vessel. The frangible connection is configured to break as a result of movement of the plug such that fluid contained within the capsule body can flow through the cap assembly and into the refillable vessel.

The cap assembly comprises a conduit extending from an upstream end configured to be in fluid communication with an internal volume of the capsule body, to a downstream end configured to discharge fluid from the capsule body into a refillable vessel. The conduit is sealed by a closure member which is connected to an inner wall of the conduit by a frangible connection.

The plug comprises a tubular body, which also defines an internal passage or conduit extending from an upstream end to a downstream end. The plug comprises a proximal-facing abutment surface configured to be brought into contact with the corresponding bearing surface of the closure member.

The plug also comprises a distal-facing abutment surface against which a rim of a refillable container may bear, if, for example, the cap system is engaged with a refillable vessel. The distal-facing abutment surface can be provided on a flange extending radially from the tubular body of the plug. Alternatively, the plug may comprise a circumferential skirt, at least partially surrounding the tubular body, on which the distal-facing abutment surface can be provided.

In an assembled system, the plug is disposed within the cap assembly and is configured to move (under the influence of an externally applied force) between a first position, in which the proximal abutment surface is positioned downstream of the frangible connection, to a second position, in which the proximal abutment surface is positioned upstream of the frangible connection. By moving the plug from the first position to the second position, the abutment surface of the plug bears against the bearing surface of the closure member and breaks the frangible connection between the conduit and the closure member. With the frangible connection between the closure member and the conduit broken, fluid contained in the capsule body can flow through the conduit of the cap assembly and through the tubular body of the plug, into a refillable vessel positioned therebelow.

The closure member is sealed within the conduit by a frangible connection extending around a periphery of the closure member. The frangible connection connects the closure member to the inner wall of the conduit. The connecting portion is configured to break when a force is applied to the closure member by proximal movement of the plug.

The abutment surface is configured to be brought into contact with the bearing surface of the closure member in such a manner that results in a net force being applied to the closure member along the longitudinal axis A, and perpendicular to the plane in which the frangible connection extends.

Accordingly, the abutment surface of the plug preferably has at least two fold rotational symmetry with respect to the longitudinal axis A. For example, the abutment surface of the plug can be provided by a continuous circumferential rim of the tubular body, terminating in a plane Q. Alternatively, the abutment surface can comprise a discontinuous rim comprising a plurality of projections equally spaced circumferentially around the rim of the tubular body, wherein the projections terminate in the plane Q. The projections may take the form of teeth spaced equally around the circumference of the rim. For example, in the case of an abutment surface comprising two teeth, the teeth may be disposed diametrically opposite each other.

Advantageously, by including projections equally spaced around the circumference of the tubular body, it may be possible to reduce the surface area of the proximal-facing abutment surface, which comes into contact with a seal to be broken. This increases the pressure applied to the bearing member (due to the reduced area over which the force is applied to the seal) and may in turn improve the reliability with which the seal fails. At the same time as reducing the surface area of the abutment surface, the equal spacing of the projections can ensure that the frangible connection is snapped, rather than asymmetrically peeling. Such an arrangement may allow the thickness of the frangible connection to be increased (thereby increasing the manufacturing tolerance), without significantly increasing the force required from the user to move the plug from the first position to the second position (e.g. by screwing the cap system onto the neck of a refillable vessel.

By providing a rotationally symmetric abutment surface configured to apply a net force along the longitudinal axis A, and perpendicular to the plane in which the frangible connection extends, the frangible connection can be configured to snap, failing around its circumference, rather than peeling from an initial breach around the seal. Such a circumferential failure of the seal can result in a snap or click sound that is audible to the user, thereby providing positive feedback that the frangible connection has been successfully broken and that the liquid contained in a capsule body can escape.

The cap assembly is preferably molded to form at least the closure member, connecting portion, and conduit as a continuous molded piece. The connecting portion may be configured to be the thinnest portion of the cap assembly. The connection portion may be between <NUM> and <NUM> thick, more preferably between <NUM> and <NUM> thick. The cap assembly can be formed from a molded polymer material, for example a polypropylene material. The polymer material can be injection molded.

For convenience, the tubular body of the plug and the conduit of the cap assembly can have a circular transverse cross-section. This can allow for easier manufacturing and assembly. However, it will be appreciated that other cross-sectional geometries are possible within the scope of the invention. For example, polygonal transverse cross-sections are also possible, as are elliptical transverse cross-sections.

The cap assembly and the plug assembly may provide further advantages in addition to the advantages described above.

According to the invention, the closure member is hollow and taper from a downstream base to an upstream peak. The downstream base may comprise an opening and the bearing surface may surround the opening. By providing an inverted hollow closure member as described above, the likelihood of the closure member settling and blocking the conduit after the seal has been broken may be reduced because the closure member can be configured to float within the fluid contained in the capsule body.

The conduit may have a first cross-sectional diameter at the upstream end and a second cross-sectional diameter at the downstream end, wherein the first cross-sectional diameter is greater than the second cross-sectional diameter.

The frangible connection may be formed between the closure member and the conduit in a region of the conduit having the second, smaller cross-sectional diameter. The plug may be configured to push the closure member into the region of the conduit with the larger diameter, as the plug is advanced in an upstream direction. In other words, the system can be configured such that the proximal-facing abutment of surface of the plug is disposed in the wider portion of the conduit when the plug is in the second position.

By providing a region of the conduit having a larger cross-sectional diameter than the maximum diameter of the closure member, the likelihood of the closure member blocking the egress of fluid through the conduit it reduced.

The cap assembly can optionally comprise an outer wall surrounding at least a portion of the wall that forms the conduit. The wall that forms the conduit will therefore be referred to hereafter as the inner wall. The outer wall can surround the inner wall and be spaced apart therefrom to form a circumferential void. The inner wall and the outer wall can be connected to each other by a connecting wall.

Depending on the position of the connecting wall, the circumferential void can be configured as an upstream void, having an open upstream end configured to receive the neck of the capsule body, or as a downstream void, having an open downstream end configured to receive at least a portion of the plug and/or the neck of a refillable vessel. It will be appreciated that a single connecting wall can provide an upstream void and a downstream void, with the connecting wall separating the two.

By providing an upstream void, security against leakage between the cap assembly and the capsule body may be improved, since the neck of the capsule body can be received in the void, between the inner wall and the outer wall. For example, the outer wall can be configured with threads on its inner surface configured to engage threads on the outer surface of the neck of the capsule body to form a sealing engagement between the outer wall of the cap assembly and the outer surface of the neck. The inner wall may be configured as a barrel seal configured to form a seal with the inner surface of the neck of the capsule body. Finally, a third sealing relationship may be formed between the rim of the capsule body and the connecting wall of the cap assembly. The skilled person will appreciate that any combination of these sealing arrangements may be implemented to provide improved security against leakage.

In addition to or as an alternative to an upstream void, a downstream void may provide additional alternatives. For example, the downstream void may fully surround the plug to prevent accidental contact with the plug, which could result in accidental rupture of the frangible connection. Moreover, downstream void can house the distal-facing abutment surface of the plug, and be configured to receive the neck of a refillable vessel. The downstream void may house a skirt wall provided on the plug, which will be described in more detail below.

In addition to the tubular body, the plug may further comprise a skirt wall that at least partially surround the tubular body. The skirt wall is spaced from the tubular body to form a plug recess therebetween. The skirt wall extends from a first end at which it is connected to the tubular body, to a free end.

The plug recess is configured to receive the downstream end of the inner wall that forms the cap assembly conduit. This can securely locate the plug within the cap assembly in the correct position and guide its movement. The depth of the plug recess also determined the maximum extend of travel of the plug within the cap assembly, since once the plug reaches its second position, the inner wall will abut the closed end of the plug recess, preventing further inward travel of the plug.

The free end can comprise the flange on which the distal-facing abutment surface is provided, and may further comprise additional features configured to engage the cap assembly to more securely retain the plug in place within the housing.

For example, the free end of the skirt may comprise a radially outwardly extending flange that provides the distal-facing abutment surface for engaging the rim of the refillable vessel. The free end of the skirt may also comprise at least one radially outwardly extending claw configured to engage at least one screw thread on an internal surface of the outer wall of the cap assembly. The claws are configured to ride over the threads as the plug is pushed from the first position to the second position. However, the claws may prevent or limit the extent to which the plugs may be shaken loose from the cap assembly during transport.

Additionally or alternatively, it may also be possible to improve the security with which the plug is maintained in the first position during transport and/or storage by providing a circumferential ridge or protrusion on the inner surface on the cap assembly conduit and/or on the outer wall of the tubular body.

To further improve the flow of fluid through the cap system, the plug may comprise one or more cut-outs to form a discontinuity in the rim of the tubular body. The one or more discontinuities may ensure that a flow path through the cap assembly is possible even if the closure member settles over the rim of the tubular body.

To provide yet further security against leakage between the capsule body and the cap system, a shrink wrap cover may be provided, extending around at least a portion of the capsule body and at least a portion of the cap assembly.

The invention will now be further exemplified with the following non-limiting figures and examples.

By way of example, the present invention is illustrated with reference to the following figures, in which:.

In the detailed description of the figures, like numerals are employed to designate like features of various exemplified devices according to the invention.

<FIG> shows a refill system for containing a concentrated cleaning fluid and configured for use with a refillable vessel. <FIG> shows a cross-sectional view of an assembled refill system comprising a capsule body <NUM>, a cap assembly <NUM>, and a plug <NUM>.

As shown in <FIG>, the capsule body <NUM> comprises a generally hollow receptacle configured to receive a volume of concentrated cleaning fluid. The concentrated cleaning fluid is contained within an internal volume <NUM> of the capsule body <NUM>. The capsule body <NUM> comprises a neck <NUM> comprising an open end surrounded by a rim <NUM>. The neck <NUM> comprises a capsule thread <NUM> configured to engage a corresponding screw thread on the cap assembly <NUM>.

As shown in <FIG>, a longitudinal axis A extends through the open end of the capsule body <NUM> from a closed end of the capsule body <NUM>, through the cap assembly <NUM>, and the plug <NUM>.

The cap assembly <NUM> is configured to seal the capsule body <NUM> and extends from an upstream end to a downstream end. The upstream direction is the direction towards the capsule body <NUM> and the downstream end direction is the direction toward the refillable vessel, when the system is in use.

The cap assembly <NUM> defines a conduit <NUM> through the cap assembly <NUM> though which fluid can flow to exit the capsule body <NUM>. The conduit <NUM> extends through the cap assembly <NUM> from an open upstream end to an open downstream end. A closure member <NUM> seals the conduit <NUM> to prevent fluid communication between the upstream end and the downstream end of the conduit <NUM>. The closure member <NUM> is sealed to the inner wall of the conduit by a frangible connection <NUM>, which can be broken by applying pressure to the closure member <NUM>.

The plug <NUM> is disposed within the cap assembly <NUM> and is configured to bear against the closure member <NUM> to break the frangible connection <NUM> as the cap assembly <NUM> is screwed onto (or otherwise engaged with) a refillable vessel. The plug <NUM> comprises a tubular body having providing an internal bore through which cleaning fluid can escape through once the plug <NUM> has been used to rupture the seal in the cap assembly <NUM>.

Advantageously, the refill system can be wrapped in a shrink wrap cover. The shrink wrap cover can cover the whole cap assembly <NUM> and the capsule body <NUM>, or it may cover only a portion of the capsule body <NUM> and the capsule assembly <NUM>. Advantageously, it may extend around the cap system such that the join between the capsule body <NUM> and the cap assembly <NUM> is surrounded by a shrink wrap cover. By shrink wrapping the capsule body <NUM> and the cap assembly <NUM> together, the likelihood of the cap assembly <NUM> being inadvertently removed from the capsule body <NUM> is further reduced.

Referring now to <FIG>, use of the system will be described in more detail.

<FIG> show an enlarged view of the refill system comprising cap assembly <NUM>, and plug <NUM>. The capsule body <NUM> is omitted for clarity. <FIG> also show the upper portion of a refillable vessel <NUM> with a neck <NUM> that defines an opening in fluid communication with an interior volume of the refillable vessel <NUM>.

<FIG> shows the system before use with the closure member <NUM> sealed within the conduit <NUM>. As shown in <FIG>, the refill system is supplied with the plug <NUM> disposed within the cap assembly <NUM>. In the configuration shown in <FIG>, the plug <NUM> occupies a first position in which it is spaced apart from (i.e. not in direct contact with) the closure member <NUM>.

The plug <NUM> is mounted within the cap assembly <NUM> such that it is secured in place against accidental movement (e.g. during transport or storage). However, the plug <NUM> and the cap assembly <NUM> are configured such that the plug <NUM> can be pushed axially towards the closure member <NUM> by bearing on a distal-facing abutment surface provided on the plug <NUM>.

The plug <NUM> can be secured or mounted within the cap assembly <NUM> in different ways. An exemplary plug and cap assembly combination will be discussed in further detail with reference to <FIG>.

The cap assembly <NUM> comprises one or more first screw threads <NUM> (or other engagement means) configured to engage a corresponding vessel screw thread on a refillable vessel <NUM>. The screw thread <NUM> allows the cap assembly <NUM> to be screwed onto the neck <NUM> of the refillable vessel <NUM>. The first screw thread(s) <NUM> are provided on an inner surface of the cap assembly <NUM>, whilst the vessel thread <NUM> of the refillable vessel <NUM> is provided on an outer surface of the refillable vessel <NUM>. Therefore, as the cap assembly <NUM> is screwed onto the neck <NUM> of the refillable vessel <NUM>, the neck <NUM> of the refillable vessel <NUM> and the rim <NUM> with which the neck <NUM> terminates are guided into the cap assembly <NUM>.

Referring now to <FIG>, the plug <NUM> is disposed within the cap assembly <NUM> such that the introduction of the neck <NUM> into the cap assembly <NUM> tends to bear against the plug <NUM>, pushing it in an upstream direction, towards the capsule body <NUM> and into contact with the closure member <NUM>.

As shown in <FIG>, as the rim <NUM> advances within the cap assembly <NUM>, the plug <NUM> is first brought into abutment with the closure member <NUM> and then begins to exert a force thereagainst as the rim <NUM> forces the plug to advance further relative to the cap assembly <NUM>. As the plug <NUM> bears against the closure member <NUM>, the force exerted against the closure member <NUM> increases to a point at which the frangible connection between the closure member and the conduit <NUM> fails, and the closure member <NUM> is pushed in an upstream direction such that it no longer seals the conduit <NUM>. <FIG> thus shows the second position of the plug <NUM>.

Once the seal provided by the closure member <NUM> is broken, concentrated cleaning fluid can flow from the internal volume <NUM> of the capsule body <NUM>, through the conduit <NUM> of the cap assembly <NUM>, through the internal bore of the plug <NUM>, and into the refillable vessel <NUM> below.

Once the capsule body <NUM> has been emptied, the cap assembly <NUM> can be unscrewed from the neck <NUM> of the refillable vessel <NUM>, and discarded safely.

By providing a refill system as described above, it is possible to provide a safe, convenient, and effective way of delivering a controlled quantity of concentrated cleaning fluid to a refillable vessel.

Several advantages may be provided by the system described here, which may result in an improved refill system.

The cap assembly <NUM> will now be described in more detail with reference to <FIG> shows a cross-sectional view of the cap assembly <NUM> described above. <FIG> shows an enlarged cross-sectional view of a frangible connection <NUM> according to a first exemplary configuration. <FIG> shows an enlarged cross-sectional view of a frangible connection <NUM> according to a second exemplary configuration. For clarity, the plug <NUM> is omitted from <FIG>.

The cap assembly <NUM> described herein includes a number of improvements that may provide enhanced performance. The cap assembly <NUM> may comprise an improved wall structure, an improved frangible connection, enhanced safety features, and improved audible and tactile feedback to the user. Each of these improvements will be described in more detail below. Moreover, it will be appreciated that the features described below may be incorporated in a refill system alone, or in combination with other features to provide a further improved product.

As shown in <FIG>, the cap assembly <NUM> comprises an inner wall <NUM> that defines a conduit <NUM> extending from an open upstream end to an open downstream end. A closure member <NUM> is positioned within the conduit <NUM> and has an upstream side 208a and a downstream side 208b. The closure member <NUM> is sealed around its periphery to the inner wall <NUM> with a frangible connection <NUM>. The frangible connection <NUM> is located between the upstream open end and the downstream open end of the conduit <NUM> and will be described as in more detail with reference to <FIG>.

An outer wall <NUM> extends around the inner wall <NUM>. The outer wall <NUM> is connected to the inner wall <NUM> by a connecting wall <NUM>. The connecting wall <NUM> extending between the inner and outer walls <NUM>, <NUM> prevents the flow of fluid through the cap assembly <NUM> in the space between the inner and outer walls <NUM>, <NUM>. The only route through which fluid may flow through the cap assembly <NUM> is thus through the conduit <NUM> when the frangible connection <NUM> has been broken.

The inner wall <NUM> is arranged coaxially within the outer wall <NUM> to form a circumferential void <NUM> between the inner and outer walls <NUM>, <NUM>. In the embodiment shown in <FIG>, the connecting wall <NUM> connects to each of the inner and outer walls <NUM>, <NUM> part way along their length. This forms an upstream void 214a between the inner and outer walls <NUM>, <NUM> upstream of the connection wall <NUM>, and a downstream void 214b between the inner and outer walls <NUM>, <NUM> downstream of the connecting wall <NUM>.

By providing an upstream void 214a, the seal between the capsule body <NUM> and the cap assembly <NUM> can be improved because the inner wall <NUM> can be specially adapted for forming a seal between the cap assembly <NUM> and the capsule body <NUM> within the neck <NUM> of the capsule body <NUM>, whilst the outer wall can be <NUM> can be specially adapted to form a seal between the cap assembly <NUM> and the capsule body <NUM> around the neck <NUM> of the capsule body <NUM>.

In at least some examples, the outer wall <NUM> can provide a child-resistant closure with the capsule body <NUM>. For example, the outer wall <NUM> can comprise a plurality of ratchet teeth (not shown) that mate with a plurality of ratchet teeth on the capsule body <NUM> to allow the cap assembly <NUM> to be screwed onto the capsule body <NUM>, but prevent the cap assembly <NUM> from being unscrewed from the capsule assembly. The child resistant closure may prevent the cap assembly <NUM> from being unscrewed from the capsule body <NUM> entirely (or at least without breaking the cap assembly <NUM>) or it may be configured to prevent the cap assembly <NUM> from being unscrewed from the capsule body <NUM> unless a predetermined axial force is applied to the cap assembly <NUM> in a direction towards the capsule body <NUM>.

Moreover, by providing an upstream void 214a to accommodate the neck <NUM> of the capsule body <NUM>, the neck <NUM> can be used to provide structural reinforcement to the cap assembly <NUM> to minimise the degree to which is flexes as pressure is applied to rupture the frangible connection <NUM>. By minimising the degree to which the cap assembly <NUM> can flex under pressure from the plug <NUM>, the frangible connection <NUM> is more likely to fail suddenly under pressure, resulting in a snap or click that provides audible and tactile feedback to the user that the seal is broken and that the concentrated liquid can be dispensed.

By providing a downstream void 214b, at least a portion of the plug <NUM> can be accommodated between the inner and outer walls <NUM>, <NUM> downstream of the connecting wall <NUM>. This provides a space in which the plug <NUM> can be retained within the cap assembly <NUM> during transport and storage, and held securely in place until the user screws the refill system onto a refillable vessel. By providing the plug <NUM> in a downstream void, the plug can be shielded from accidental contact by handlers, thereby reducing the risk that the plug <NUM> is accidentally moved between the first and second positions during transit or storage.

It will be appreciated that although the provision of an upstream void 214a and a downstream void 214b can be combined to provide enhanced advantages over known systems, in at least some examples the cap assembly <NUM> can comprise only an upstream void 214a or only a downstream void 214b.

The conduit <NUM> provided by the inner wall <NUM> of the cap assembly <NUM> can have a variable diameter along its length. For example, the diameter of the conduit <NUM> upstream of the frangible connection <NUM> can be larger than the diameter of the conduit <NUM> downstream of the frangible connection <NUM>. By increasing the diameter of the conduit <NUM> upstream of the frangible connection <NUM>, the closure member <NUM> can be pushed by the plug <NUM> into a region of the conduit <NUM> that has a larger diameter than the closure member <NUM>. This further reduces the likelihood that the closure member <NUM> can occlude the conduit <NUM> to prevent the egress of cleaning fluid from the capsule body <NUM> through the cap assembly <NUM> and the plug <NUM>, once the plug has been moved to its second position.

In the embodiment shown in <FIG>, the inner wall <NUM> is shaped with a barrel shaped or bulbous upstream end portion to provide a barrel seal for sealing with the neck <NUM> of the refill capsule body <NUM>. The inner wall <NUM> is configured to sit within the opening of the capsule body <NUM> and form a seal between an outer surface of the inner wall and an inner surface of the opening.

Instead of comprising a cylindrical shape having sides that are substantially parallel, the upstream end of the conduit <NUM> can be barrel shaped, steadily decreasing in transverse cross-sectional diameter (i.e. a cross-section in a plane perpendicular to the longitudinal axis A) from a maximum diameter upstream of the frangible connection <NUM> towards the upstream rim of the inner wall <NUM>. By varying the diameter of the conduit <NUM> at the upstream end, variation in manufacturing tolerances can be accounted for and/or a tighter seal can be provided between the capsule body <NUM> and the cap assembly <NUM> because the narrower open end of the conduit <NUM> can be inserted into the neck <NUM> of the capsule body <NUM>, and a tight seal can be formed between the barrel sealing rim and the neck of the capsule body <NUM>.

As shown in <FIG>, the connecting wall <NUM> may further comprise a circumferential notch <NUM> or channel adjacent the inner wall <NUM> on the upstream side. The notch <NUM> reduces the thickness of the connecting wall <NUM> at the point where the inner wall <NUM> joins the connecting wall <NUM>. This can increase the degree to which the upstream portion of the inner wall <NUM> can flex inwardly to fit within the neck <NUM> of the capsule body <NUM> (as shown in <FIG>).

The inner wall <NUM> downstream of the closure member <NUM> has a generally cylindrical form, with substantially parallel walls. The downstream end of the inner wall <NUM> is configured to fit within the neck <NUM> of the refillable vessel <NUM>.

As shown in <FIG>, the inner surface of the inner wall <NUM> can comprise a radially inwardly protruding ridge or protrusion <NUM>. The ridge or protrusion <NUM> can advantageously engage a corresponding protrusion on the plug <NUM>, as will be described in more detail below with reference to <FIG>.

As shown in <FIG>, the closure member <NUM> is positioned within the conduit <NUM> and closes the conduit to prevent the passage of fluid therethrough unless the frangible connection <NUM> is broken.

The closure member <NUM> shown in <FIG> comprises a tapered shape, extending from a downstream base <NUM> to an upstream peak <NUM>. For example, the closure member can comprise a conical or frustoconical shape. The base <NUM> is preferably open to allow access to the hollow interior of the closure member <NUM> from the downstream side. By providing a hollow, peaked closure member <NUM>, the likelihood of the closure member <NUM> settling over the opening formed through the inner conduit after the seal has been broken is reduced. To the contrary, the buoyancy provided by the hollow closure member <NUM> means that the closure member tends to float away from the conduit <NUM>.

The base <NUM> of the closure member provides a bearing surface <NUM> against which the plug <NUM> can bear to apply pressure to rupture the frangible connection <NUM>. The bearing surface <NUM> preferably extends in a plane that is orthogonal to the longitudinal axis A. The frangible connection <NUM> preferably also extends in a plane perpendicular to the longitudinal axis A. The frangible connection <NUM> can extend in the same plane as the bearing surface <NUM>, or in a plane parallel to the plane R.

<FIG> each show an enlarged view of a frangible connection <NUM> formed between the closure member <NUM> and the inner wall <NUM> according to the invention.

As shown in <FIG>, the frangible connection <NUM> extends between the inner wall <NUM> and an outer perimeter of the closure member <NUM>. The frangible connection <NUM> is preferably between <NUM> and <NUM> thick. However, the skilled person will appreciate that other dimensions may be chosen depending on the materials used and the dimensions of the cap system.

The thickness (in a longitudinal direction) and the width (in a radial direction) of the frangible connection are preferably closely controlled. By controlling the width and the thickness of the frangible connection <NUM>, the reliability with which the frangible connection <NUM> fails may be more reliable. This may provide a more consistent user experience.

The thickness and the width of the frangible connection can be controlled in different ways.

For example, in the exemplary configuration shown in <FIG>, the frangible connection <NUM> is formed between two opposing recesses or notches <NUM>, <NUM>. The recesses or notches <NUM>, <NUM> are shown in <FIG>, which is a cross-sectional view. However, it will be appreciated that for a closure member <NUM> having a circular transverse cross-section, the recesses, or notches <NUM>, <NUM> may be formed as circumferential channels or annular grooves.

The first recess <NUM> is formed upstream of the frangible connection <NUM>, between an upstream side 208a of the closure member <NUM> and an interior surface of the inner wall <NUM>. The second recess <NUM> is formed downstream of the frangible connection <NUM>, between a downstream side 208b of the closure member <NUM> and an interior surface of the inner wall <NUM>. By forming a frangible connection <NUM> between two opposing recesses or channels, the thickness (in a longitudinal direction) and the width (in a transverse direction) of the frangible connection <NUM> can be controlled and minimised.

The notches <NUM> and <NUM> (or the channels) extend from an open end to a closed end, with the frangible connection <NUM> forming the closed end in each case. The closed end of each recess or channel may advantageously have a rounded profile, as shown in <FIG>. By providing a frangible connection <NUM> between opposing rounded notches or channels, the width of the frangible connection at the thinnest part can be closely controlled.

It will be appreciated that the transverse width of the thinnest part of the frangible connection <NUM> can be controlled by varying the radius of curvature of the rounded notches. The radius of curvature of the first notch or recess <NUM> can be chosen to be substantially the same as the second notch or recess <NUM> or it may be different.

The second (downstream) notch or channel <NUM> in the example illustrated in <FIG> means that the frangible connection <NUM> extends in a different plane to the bearing surface <NUM>. However, in an alternative exemplary configuration, the second circumferential notch <NUM> can be omitted.

An alternative exemplary configuration is shown in <FIG>. As shown in <FIG>, the first (upstream) recess <NUM> is present. In the illustrated configuration, the recess <NUM> comprises a closed end, having a flat lower surface <NUM>. The flat lower surface <NUM> of the recess <NUM> extends between the inner wall <NUM> and the closure member <NUM> and forms the upper surface of the frangible connection <NUM>.

The lower surface of the frangible connection <NUM> extends in the same plane as, and is contiguous with, the bearing surface <NUM>. As shown in <FIG>, the width of the frangible connection <NUM> at its thinnest part can be controlled by forming the recess <NUM> such that the inner surface of the inner wall <NUM> immediately upstream of the frangible connection <NUM> is positioned radially outwardly or the inner surface of the inner surface of the inner wall <NUM> immediately downstream of the frangible connection <NUM>. By offsetting in the point at which the inner surface of the inner wall <NUM> upstream of the frangible connection <NUM> with respect to the inner surface of the wall downstream of the frangible connection, the width of the frangible connection <NUM> at its thinnest point can be reduced to a dimension that is smaller than the width of the recess <NUM>. This allows the formation of a frangible <NUM> connection having a width dimension smaller than any of the parts required to form the connection (e.g. in the mold). This can allow for a further improved frangible connection <NUM>.

Referring again to <FIG>, the frangible connection <NUM> preferably extends in a plane P that is orthogonal to the longitudinal axis A of the cap assembly <NUM>. By providing a flat seal (with respect to the longitudinal axis A), the frangible connection <NUM> tends to snap arounds its circumference at substantially the same time as the plug <NUM> (with its proximal-facing abutment surface <NUM> also oriented orthogonal to the longitudinal axis A) bears on the bearing surface <NUM>. This is contrast to a frangible connection <NUM> that extends in a plane extending at a non-perpendicular angle to the longitudinal axis A, which tends to peel from the 'lower' end (the portion of the frangible connection <NUM> that is first brought into close proximity with the plug <NUM>) towards the 'upper' end (the portion of the seal that is furthest from the advancing plug <NUM>). Such peeling is often imperceptible to the user of the assembly, and may result in the user removing the cap assembly from the refillable vessel prematurely with the seal partially intact.

By contrast, one of the advantages of the frangible connection <NUM> breaking around the perimeter of the closure member <NUM> at the same time is that the frangible connection <NUM> may fail suddenly, causing a snap or click as the frangible connection <NUM> is broken.

The snap or click failure of the frangible connection <NUM> can provide audible and/or tactile feedback to the user that the component sealing the refill system has been broken and that the concentrated cleaning fluid disposed within the capsule body <NUM> will be dispensed.

In the embodiments shown in <FIG>, the system is configured such that the movable plug <NUM> bears against the bearing surface <NUM> of the closure member <NUM> as the plug <NUM> is moved.

The plug <NUM> will now be described in more detail with reference to <FIG>.

The plug <NUM> described herein includes a number of improvements that may provide enhance performance. The plug <NUM> may comprise an improved wall structure, an improved bearing surface for rupturing the frangible connection <NUM>, enhanced safety features, and features that contribute to improved audible and tactile feedback to the user. Each of these improvements will be described in more detail below. Moreover, it will be appreciated that the features described below may be incorporated in a refill system alone, or in combination with other features to provide a further improved product.

<FIG> shows a cross-sectional view of the plug <NUM> comprising a proximal-facing abutment surface configured according to a first exemplary configuration. <FIG> shows a cross-sectional view of the plug <NUM> comprising a proximal-facing abutment surface configured according to a second exemplary configuration. <FIG> shows a perspective view of the plug <NUM> of <FIG>.

As shown in <FIG>, the plug <NUM> comprises a generally tubular body <NUM> defining an internal conduit therethrough, with a proximal rim <NUM> surrounding an upstream opening of the tubular body <NUM>. The proximal rim <NUM> comprises a proximal-facing abutment surface <NUM> configured to bear against the bearing surface <NUM> of the closure member <NUM> as the plug <NUM> is moved from the first position, to the second position, as described above.

In the embodiment shown in <FIG>, the plug <NUM> further comprises a generally tubular skirt wall <NUM> that is arranged coaxially with respect to the tubular body <NUM>, and surround the tubular body <NUM> along at least part of its length to provide a dual-walled plug <NUM>. The skirt wall <NUM> is spaced apart from the tubular body <NUM> (in a radial direction) to form a plug recess <NUM> between the skirt wall <NUM> and the tubular body <NUM>.

The skirt wall <NUM> is connected at its distal end to the distal end of the tubular body <NUM>, and comprises a free proximal end. The free proximal end of the skirt <NUM> further comprises an outwardly extending flange <NUM> that provides a distal-facing abutment surface <NUM> for abutting a rim <NUM> of a refillable vessel <NUM> (see <FIG>).

By providing a plug <NUM> comprising an inner tubular body <NUM> and an outer skirt <NUM>, the plug <NUM> can be more securely retained within the cap assembly <NUM>. For example, the plug recess <NUM> can accommodate a component (e.g. inner wall <NUM>) of the cap assembly <NUM> to retain the plug <NUM> securely within the cap assembly <NUM> until the user screws the system onto a refillable vessel <NUM>.

The proximal-facing abutment surface <NUM> can be configured in different ways, as will now be described with reference to <FIG>.

As described above, the proximal-facing abutment surface <NUM> of the plug <NUM> is configured to be brought into contact with the bearing surface <NUM> of the closure member <NUM> as the plug <NUM> moves between its first position and its second position (see <FIG>). As the proximal-facing abutment surface <NUM> is brought into contact with the bearing surface <NUM> of the closure member <NUM> and advanced further in a proximal direction, the frangible connection <NUM> breaks and the closure member <NUM> is lifted away from a position in which it occludes the conduit <NUM>.

The proximal-facing abutment surface <NUM> of the plug can be configured to distribute the applied force evenly around the circumference of the frangible connection <NUM>. In other words, the proximal-facing abutment surface <NUM> can be configured in such a manner that results in a net force being applied to the closure member <NUM> along the longitudinal axis A, and perpendicular to the plane in which the frangible connection <NUM> extends. Accordingly, the proximal-facing abutment surface <NUM> of the plug <NUM> preferably has at least two fold rotational symmetry with respect to the longitudinal axis A.

In the exemplary configuration shown in <FIG>, the proximal-facing abutment surface <NUM> of the plug <NUM> is provided by a circumferential rim <NUM> of the tubular body <NUM>, terminating in a plane. By providing a circumferential rim in a plane perpendicular to the longitudinal axis A, the proximal-facing abutment surface <NUM> is simultaneously brought into contact with the bearing surface <NUM> around the circumference of the closure member <NUM>.

The rim <NUM> that provides the proximal-facing abutment surface <NUM> may be continuous or can comprise one or more cut-outs <NUM>.

In an alternative shown in <FIG>, the proximal-facing abutment surface <NUM> can comprise a discontinuous rim comprising a plurality of projections <NUM> (extending in a proximal direction) equally spaced circumferentially around the rim <NUM> of the tubular body <NUM>, wherein the projections <NUM> terminate in a plane perpendicular to longitudinal axis A. The projections may take the form of teeth spaced equally around the circumference of the rim. For example, in the case of an abutment surface comprising two teeth, the teeth may be disposed diametrically opposite each other. A perspective view of a plug <NUM> comprising two diametrically opposed teeth is shown in <FIG>.

By providing a rotationally symmetric abutment surface configured to apply a net force along the longitudinal axis A, and perpendicular to the plane in which the frangible connection <NUM> extends, the frangible connection <NUM> can be configured to snap, failing around its circumference, rather than peeling asymmetrically from an initial breach around the seal. Such a circumferential failure of the seal can result in a snap or click sound that is audible to the user, thereby providing positive feedback that the frangible connection has been successfully broken and that the liquid contained in a capsule body can escape.

In addition or as an alternative to the features described above, the plug configurations described above can comprise additional feature to enhance the functionality of the plug <NUM>. The following additional features may be combined with the abutment surface configurations described above with reference to <FIG>.

The distal-facing abutment surface <NUM> at the free end of the skirt wall <NUM> can be configured to provide multiple additional advantages. For example, the free end of the skirt wall <NUM> can comprise a proximal seal <NUM> configured to seal against the connecting wall <NUM> of the cap assembly <NUM>. The proximal seal <NUM> can comprise a circumferential ridge comprising a peak. The peak provides a small surface area to be brought into contact with the connecting wall <NUM>, thereby improving the seal.

The free proximal end of the skirt wall <NUM> can also comprise a one or more claws <NUM> configured to engage the threads <NUM> of the cap assembly <NUM>. The engagement of the claw(s) <NUM> with the thread <NUM> can provide additional security that the plug <NUM> will remain in place within the cap assembly <NUM>.

The claw(s) <NUM> may also retain the plug <NUM> within the cap assembly <NUM> after the product has been used. Since the plug <NUM> must be pushed into the cap assembly <NUM> to rupture the frangible connection <NUM>, the claws are preferably configured to such that they can ride over the threads <NUM> of the cap assembly <NUM> as the plug <NUM> advances towards the closure member <NUM>. The claw(s) <NUM> may thus comprise a distal facing concave surface and a convex proximal surface.

As shown in <FIG>, the plug <NUM> may further comprise a circumferential ridge or protrusion <NUM> on an outer surface of the tubular body <NUM>. The ridge or protrusion <NUM> can be configured to engage with a corresponding ridge or protrusion (e.g. ridge <NUM>) on a complementary cap assembly <NUM>. This may further improved the retention of the plug <NUM> within the cap assembly <NUM> before use, for example during transport and storage.

As shown in <FIG>, the plug <NUM> can also comprise one or more cut-outs or slots <NUM> in the wall of the tubular body <NUM>. The cut-outs or slots preferably extend from the proximal rim <NUM> of the tubular body <NUM> in a distal direction. The discontinuity in the rim <NUM> formed by the cut-outs or slots <NUM> may advantageously improve the flow of fluid through the cap assembly <NUM> and the plug <NUM> after the frangible connection <NUM> has been broken, by ensuring that the closure member <NUM> cannot form a seal against the rim <NUM> of the plug <NUM>.

In the embodiment shown in <FIG>, the plug <NUM> comprises two diametrically opposed cut-outs <NUM> (although only one is visible in the cross-sectional view shown in <FIG>). However, one cut-out may be provided, or three or more cut-outs can be provided in the tubular body <NUM>.

Providing a discontinuity in the proximal-facing abutment surface <NUM> of the tubular body <NUM> may also provide the additional advantage of reducing the surface area of the proximal-facing abutment surface <NUM> that is brought into contact with the bearing surface <NUM> of the closure member <NUM>, thereby increasing force per unit area exerted on the closure member <NUM>.

Although not illustrated in the drawings, it will be appreciated that the closure member <NUM> may be modified (in addition to or as an alternative to the plug <NUM>) to enhance the flow of cleaning fluid through the plug <NUM> and cap assembly <NUM> in a similar manner. For example, the closure member <NUM> may be modified to provide a discontinuity, such as a cut-out or recess, in the bearing surface <NUM> of the closure member <NUM> that prevents the closure member <NUM> from forming a seal with the plug <NUM> after the frangible connection <NUM> has been broken.

As will be appreciated, a plug <NUM> comprising a planar rim <NUM> and a closure member <NUM> comprising a planar bearing surface <NUM> may form a seal against each other in the event that the closure member <NUM> settles over the opening of the tubular member <NUM> of the plug <NUM>. Should the planar surfaces align and come into contact to form a seal around the perimeter of the rim <NUM>, the closure member <NUM> could prevent the egress of fluid from the capsule body <NUM> after the frangible connection <NUM> has been broken.

However, by providing one or more cut-outs or slots in either (or both) of the rim <NUM> or the bearing surface <NUM>, in the event that the closure member <NUM> settles against the tubular body <NUM> of the plug <NUM>, fluid contained in the capsule body <NUM> may still flow through the tubular body <NUM> of the plug <NUM> by way of the openings formed by the slots of cut-outs.

As shown in <FIG>, the plug <NUM> may further comprise at least one barrier or beam <NUM> that extends across the distal opening of the tubular body <NUM>. The beam <NUM> may extend across the diameter of the distal opening, or multiple beams can extend across the opening. The beam is configured to allow the flow of fluid therepast, but prevent or restrict the insertion of an object (e.g. a finger) into the conduit formed by the tubular body <NUM>. This minimises the likelihood of the frangible connection <NUM> being broken inadvertently or improperly by way of an object passing through the tubular body <NUM>.

As will now be described with reference to <FIG>, when assembled, the capsule body <NUM>, the cap assembly <NUM>, and the plug <NUM> can provide a system providing yet further advantages.

<FIG> shows an enlarged view of the distal end of the refill system. The neck <NUM> of the capsule body <NUM> is clearly shown, and the rim <NUM> that surrounds the opening in the neck <NUM>. The neck <NUM> of the capsule body <NUM> also comprises one or more threads <NUM> extending around the neck <NUM> (on an outer surface), which are configured to engage corresponding threads in the cap assembly <NUM>.

The cap assembly <NUM> is also clearly shown. The cap assembly <NUM> comprises the dual walled construction described above with reference to <FIG>. An inner surface of the outer wall <NUM> comprises one or more second screw threads <NUM> that are configured to engage the threads <NUM> on the capsule body <NUM>.

The cap assembly <NUM> is screwed onto the capsule body <NUM> such that the rim <NUM> of the neck <NUM> is disposed within the upstream void 214a. Advantageously, the rim <NUM> of the neck <NUM> abuts the connecting wall <NUM> of the cap assembly <NUM>. By engaging the capsule body <NUM> with the cap assembly <NUM> such that the rim <NUM> of the capsule body <NUM> abuts the connecting wall of the cap assembly <NUM>, the neck <NUM> of the connecting wall <NUM> against flexing as the plug <NUM> bears against the closure member <NUM>. Moreover, by abutting the rim <NUM> of the capsule body <NUM> against the connecting wall <NUM> of the cap assembly <NUM>, additional security against leakage from the capsule body <NUM> can be provided.

The cap assembly <NUM> is further configured such that the upstream end of the inner wall <NUM> (which is optionally configured as a barrel shaped seal, as described above) is disposed within the neck <NUM> of the capsule body <NUM>. The inner wall <NUM> thus forms an additional seal with the neck <NUM> of the capsule body <NUM>.

The engagement between the plug <NUM> and the cap assembly <NUM> will now also be described with reference to <FIG>. As shown in <FIG>, the plug <NUM> is disposed within the cap assembly <NUM>. The plug <NUM> shown in <FIG> is structurally similar to the plug <NUM> described with reference to <FIG>.

As illustrated, the plug <NUM> is disposed within the cap assembly <NUM> such that the distal end of the inner wall <NUM> of the cap assembly <NUM> is disposed within the recess <NUM> formed between the tubular body <NUM> and the skirt wall <NUM>. During assembly, the ridge <NUM> on the plug <NUM> is pushed passed the corresponding ridge <NUM> on the inner wall <NUM> of the cap assembly <NUM>. The engagement of the ridges <NUM> and <NUM> may help to retain the plug <NUM> within the cap assembly <NUM> during transport and storage of the system <NUM>.

The one or more claws <NUM> of the plug <NUM> may also help to retain the plug <NUM> within the cap assembly <NUM> by engaging the threads <NUM> on the interior surface of the outer wall <NUM>. Preferably, at least two claws are provided to securely engage the thread(s) <NUM> on of the cap.

The combination of the plug <NUM> and the cap assembly <NUM> described herein may be configured to prevent the closure member <NUM> blocking the flow of fluid through the cap assembly <NUM> after the frangible connection <NUM> has been broken.

For example, as illustrated in the embodiment shown in <FIG>, the inner wall <NUM> of the cap assembly <NUM> can be configured to have a first diameter downstream of the frangible connection <NUM> and a second, larger diameter upstream of the frangible connection <NUM>. To ensure that the closure member <NUM> is pushed or lifted into a position in which it cannot seal against the inner wall <NUM> of the cap assembly <NUM> after the frangible connection <NUM> has been broken, the plug <NUM> can be configured such that the rim or abutment surface <NUM> can be moved upstream past the point at which the frangible connection <NUM> joins the closure member <NUM> to the inner wall <NUM>. This can be achieved by ensuring that the maximum distance of travel of the plug <NUM> is not limited by the cap assembly <NUM> until the rim <NUM> has pushed the closure member <NUM> into the increased diameter portion of the conduit <NUM>.

In the example shown in <FIG>, the maximum travel of the plug <NUM> towards the frangible connection <NUM> is the point at which the seal <NUM> on the skirt wall <NUM> abuts the connecting wall <NUM> of the cap assembly <NUM>. In the embodiment illustrated, the rim <NUM> of the tubular body <NUM> and the seal <NUM> terminate in the same transverse plane. To ensure that the travel of the plug <NUM> is not limited until after the closure member has been lifted away from the narrower part of the conduit <NUM>, the frangible connection <NUM> is positioned downstream of the connecting wall <NUM>.

Alternatively (or additionally), the rim or abutment surface <NUM> of the plug <NUM> can extend proximally beyond the sealing surface <NUM> of the skirt wall <NUM>.

The capsule body <NUM>, cap assembly <NUM>, and plug <NUM> can be made of any suitable material known in the art. For example, the capsule body <NUM>, cap assembly <NUM>, and the plug <NUM> may be made of polyethylene or polypropylene, and may be formed by injection moulding techniques. Advantageously, the capsule body <NUM> can be formed of polyethylene, whilst the cap assembly <NUM> and the plug <NUM> can be formed of polypropylene.

It will be appreciated that aspects of the present invention include embodiments in which the features described above are provided alone or in combination with other features described here. For example, the frangible connection described above can be provided in a refill system having a cap assembly that screws directly onto the neck of a refillable vessel. In such systems, the cap can be configured such that the rim of the refillable vessel bears directly on the closure member to break the frangible connection and allow concentrated cleaning fluid to flow through the cap assembly into the refillable vessel.

Moreover, the plug described herein may be provided in a cap assembly having a different sealing arrangement to the arranged described herein. For example, the cut-outs and slots in the plug assembly that prevent a closure member sealing against the opening in the plug can be employed in cap assemblies with different structures, and with different closure members.

Claim 1:
A cap system comprising:
a cap assembly (<NUM>) comprising:
an inner wall (<NUM>) defining a conduit (<NUM>) through the cap assembly (<NUM>), the conduit (<NUM>) extending from an upstream end to a downstream end; and
an outer wall (<NUM>) surrounding the inner wall (<NUM>) and spaced from the inner wall (<NUM>) to define a circumferential void (214a, 214b) between the inner and outer walls (<NUM>, <NUM>);
wherein the cap assembly (<NUM>) further comprises a closure member (<NUM>) configured to seal the conduit (<NUM>), the closure member (<NUM>) comprising an upstream side (208a) and a downstream side (208b), and a bearing surface (<NUM>) on its downstream side (208b);
wherein the closure member (<NUM>) is sealed to the inner wall (<NUM>) with a frangible connection (<NUM>) located between proximal and distal ends of the conduit (<NUM>),
wherein the frangible connection (<NUM>) extends in a first plane, which is orthogonal to a longitudinal axis (A) of the conduit (<NUM>); and
wherein the system further comprises a plug (<NUM>) comprising:
a tubular body (<NUM>) with an open proximal end and an open distal end, wherein the open proximal end is surrounded by a first rim (<NUM>), and wherein the rim (<NUM>) further comprises a proximal abutment surface (<NUM>), extending in a second plane, for bearing against the bearing surface (<NUM>) of the closure member (<NUM>),
wherein the plug (<NUM>) further comprises an outwardly extending flange (<NUM>) comprising a distal-facing abutment surface (<NUM>) for abutting a rim (<NUM>) of a refillable vessel (<NUM>), and
wherein the plug (<NUM>) is movable between a first position, in which the proximal abutment surface (<NUM>) is located downstream of the frangible connection (<NUM>), and a second position in which the proximal abutment surface (<NUM>) is located upstream of the frangible connection (<NUM>), to thereby break the frangible connection (<NUM>), and
wherein abutment surface (<NUM>) is configured to bear against the bearing surface of the closure member as the plug moves from the first position to the second position such that a net force applied to the closure member is along the longitudinal axis A, and perpendicular to the first and second planes
characterized in that
the closure member (<NUM>) is hollow, and tapers from a downstream base (<NUM>) to an upstream peak (<NUM>).