Syphon assembly and actuator therefor

A fill valve assembly (9, 109) for connection with a flushing syphon or other flushing valve. The assembly (9, 109) includes a float operated equilibrium valve (90, 190) and a branch element (92, 192) fluidly connected upstream the equilibrium valve (90, 190) and including an outlet (98) for providing fluid flow to one or more fluid pressure driven actuators (6).

This invention relates to valve assemblies and more particularly to a valve assembly for use in flushing cisterns. More specifically, although not exclusively, this invention relates to fill valve assemblies for use with flushing systems incorporating a draining syphon or other flushing valves.

This invention relates to syphon assemblies for flushing cisterns and actuators for operating such syphon assemblies. More specifically, although not exclusively, this invention relates to a syphon assembly incorporating a piston that is operated by an actuator for initiating the syphonic action and to the actuator assembly.

Draining syphons of this kind are generally operated by a lever whose end is connected to a piston rod attached to the piston such that actuation of the lever raises the piston, thereby raising the level of water within the syphon over the bight of the U and priming the syphon to initiate the syphonic action. Actuation of the piston requires a significant amount of force as it involves displacing a considerable volume of water.

It is a non-exclusive object of the invention to provide a draining system with one or more components that overcomes or at least mitigates the issues associated with known systems. It is a more general non-exclusive object of the invention to provide an improved cistern draining system.

According to one aspect of the present invention there is provided a valve assembly, for example a fill valve assembly for inclusion or incorporation into a cistern flushing system or assembly, e.g. a syphon assembly as described below or a different type of flushing valve, the assembly comprising a float operated equilibrium valve and a branch element operatively and/or fluidly connected upstream the equilibrium valve and including an outlet for providing fluid flow to one or more fluid pressure driven actuators.

The branch element is preferably be integral with the fill valve assembly, for example such that the assembly is provided as a unitary structure, e.g. with a unitary or common housing, which may be provided in two or more parts secured together as unitary structure.

The branch element may extend from the fill valve assembly, for example at an angle which may be a right angle with respect to the flow direction, e.g. horizontally in use. The fill valve assembly may comprise two or more outlets, each of which may be at different positions and/or orientations on or in the fill valve assembly, for example wherein the branch element may be selectively connected or operatively or fluidly connected to, one of the outlets. In embodiments, the fill valve assembly comprises two outlets on opposed portions or sides of the fill valve assembly, for example such that the branch element may be connected to the fill valve assembly at one of its sides and/or in one of two orientations, e.g. which orientations may be at a straight or 180° angle with respect to one another.

The fill valve assembly may comprise one outlet on either of its sides for cooperative and/or sealing engagement with an inlet or inlet member of the branch element. The fill valve assembly may further comprise a clamp element for securing the branch element or the inlet or inlet member thereof to the fill valve assembly or to one of its sides and/or in cooperative engagement and/or with respect to one of the outlets. The branch element may be reversible.

In some embodiments, the branch element or inlet or inlet member may comprise an inlet spigot and/or may comprise a portion that is receivable within or that receives at least a portion of one of the outlets. The branch element or inlet or inlet member or spigot or portion thereof may comprise a flange or groove, for example a circumferential flange or groove, for engaging with the clamp element. The clamp element may be shaped to match the contours of at least a portion of the branch element or inlet or inlet member or inlet spigot or flange or groove. The clamp element may comprise a receptacle, for example a U-shaped or C-shaped receptacle, which may have an undersized neck, e.g. to provide a snap fit with a portion of the branch element or inlet or inlet member or inlet spigot. Preferably, the clamp element comprises two receptacles each for connecting and/or securing the branch element to one of the two outlets. The clamp element may comprise one or more flanges, e.g. inwardly extending radial flanges, for cooperation with the aforesaid portion. The or at least one of the or each, radial flange may extend inwardly, for example from a respective hollow portion, which may be part cylindrical, and/or may be U-shaped or C-shaped and/or circumscribe more than half 180° and/or may include a lead-in, e.g. to facilitate insertion.

In other embodiments, the branch element or inlet or inlet member may comprise a receptacle or ring portion within which is received one or both of the outlets. The branch element or inlet or inlet member may be connectable in one of two or more orientations, for example a first orientation in which the branch element is aligned at least partially with a first of the outlets and/or a second orientation in which the branch element is aligned at least partially with a second of the outlets. The branch element may comprise locating means, such as a locating flange or recess, that may be configured to cooperate with a locating means, such as a locating recess or flange, on or of the fill valve assembly or a housing thereof or the equilibrium valve.

The assembly or branch element may comprise a non-return means or valve or a restriction means, e.g. a flow restrictor, and/or a filter and/or an outlet that may include a push fit fitting. The fill valve may comprise a float pivotally mounted with respect to the equilibrium valve, for example via a lever that may selectively close a bleed port of the equilibrium valve to selectively open and/or close the equilibrium valve.

Another aspect of the invention provides a syphon assembly for discharging water from a cistern, the assembly comprising an inverted generally U shaped duct having an upleg and a downleg, an open-ended, e.g. enlarged, chamber fluidly connected to the upleg, a piston movable in the chamber and an actuator, e.g. a power-driven actuator, operatively connected to the piston, wherein the actuator is operable to move, in use, the piston, or at least assist in the movement thereof, within the chamber to initiate a syphonic flushing action, for example under the influence of an external source of power.

The use of a power-driven actuator to operate the piston obviates the need to apply substantial force to initiate the flush.

As used herein, the term “power-driven actuator” means an actuator that is configured, in use, to be driven by, or whose operation is at least assisted by, an external source of power, such as one or more of a source pressurised fluid, an electrical power source or some other source of power. For example, the power-driven actuator may comprise a fluid-driven, or fluid pressure-driven, e.g. hydraulically-driven or pneumatically-driven, actuator and/or an electrically-driven or electro-mechanically-driven actuator.

In some embodiments, the syphon assembly comprises a flush activator in the form of a push button or lever that is operatively and/or mechanically connected to the piston, for example to raise the piston, e.g. thereby to initiate the syphonic flushing action. In such embodiments, the syphon assembly may comprise a mechanism for moving or raising the piston and/or the actuator may be configured to assist in the movement of the piston and/or may be connected, for example continuously connected, to a source, e.g. of power, such as fluid, e.g. pressurised fluid, or an electrical power source or any other source of external power.

The assembly may further comprise a piston rod with a first connector or connection means at a first end, e.g. for connecting to the piston, and/or the first end may be connected to or formed integrally with the piston. Additionally or alternatively, the piston rod may comprise a second connector or connection means at a second end, for example opposite the first end, e.g. for connecting to the actuator or to a prime mover of the actuator and/or the second end may be connected to or formed integrally with at least part of the actuator, e.g. a prime mover thereof. Preferably, the piston rod extends through the chamber, for example a wall of the cylinder, which may be an upper wall in use.

Another aspect of the invention provides a power-driven actuator, for example configured use with the syphon assembly described above, the actuator may comprise a prime mover and/or a piston rod that may be connected at a first end thereof to the prime mover, e.g. by a first connector or connection means, and/or a second connector or connection means adapted to connect, in use, to a piston, e.g. for driving the piston.

For the avoidance of doubt, any of the features described herein apply equally to any aspect of the invention.

The actuator may be driven hydraulically and/or pneumatically and/or electromechanically. The actuator may comprise a hydraulic or pneumatic or electro-mechanical actuator. The actuator may be connected or connectable to one or more of a source of pressurised fluid, e.g. a pneumatic or hydraulic fluid, an electrical power source or some other source of power.

The actuator is preferably connected or connectable, in use, to a fluid or liquid or water or air supply, for example a pressurised fluid or liquid or water or air supply, such as by a pipe or tube or hose, which may be flexible. More preferably, the actuator is a hydraulic actuator, which may be fluidly connected, in use, or connectable to a mains water supply, e.g. domestic or commercial mains water supply, e.g. to drive the operation of the actuator.

This is particularly advantageous, since domestic and indeed commercial cisterns are invariably connected to a mains water supply for filling the cistern. Thus, such a device makes use of a pre-existing feature of cisterns without the need for connection to, for example, an electric power supply.

In some embodiments, the actuator is operatively and/or fluidly connected or connectable to the or a fill valve, for example to or via a branch element thereof. The branch element may be operatively or fluidly connected or connectable or comprised or integrated in a fill valve assembly, preferably upstream of a valve or valve member thereof.

The prime mover of the actuator may comprise an actuator piston, which may comprise a piston head and/or may be reciprocable within an actuator cylinder. The actuator cylinder may comprise an inlet at or adjacent a first of its ends and/or a vent at or adjacent at a second of its ends, for example two or more, e.g. three or more, preferably four peripheral vents or slots. The actuator cylinder may further comprise a cap, for example an anti-splash cap, which may cover and/or surround the vent and/or be mounted over or adjacent thereto and/or is spaced therefrom. Preferably, the actuator piston or piston head is sized and/or dimensioned such that a fluid flow entering the cylinder from the inlet forces the piston from the first end toward the second end. More preferably, the actuator piston or piston head is sized and/or dimensioned such that fluid, e.g. some or a predetermined amount of fluid, is able to flow, e.g. at a predetermined flowrate, between the actuator piston or piston head and the cylinder, for example in the absence of a fluid flow from the inlet. More preferably, the actuator piston or piston head and the actuator cylinder vent are each configured such that the actuator provides a pre-determined actuator force.

The actuator may comprise or be connected or connectable, e.g. in use, to, and/or controlled or controllable, e.g. in use, by a control valve or control valve means or assembly. The control valve or control valve means or assembly may comprise an operating or equilibrium valve and/or a pilot or bleed valve and/or a control lever or button or proximity sensor or switch, for example a touchless or soft touch sensor or switch, one or more of which, e.g. each of which, may be operatively connected together. Preferably, the syphon assembly or the control valve or control valve means or assembly comprises a control lever or button or proximity sensor or switch that operates the pilot valve, which in turn may activate or operate or open the operating valve. More preferably, the control lever or button or proximity sensor or switch causes, e.g. on activation thereof, the bleed valve to open, which may release pressure from the equilibrium valve, for example a pressure chamber thereof, e.g. thereby opening the equilibrium valve. The connection between the pressure chamber and the pilot or bleed valve may be provided by a tube, for example a hydraulic tube.

The operating or equilibrium valve may be mounted to or adjacent to or otherwise associated with the syphon assembly or chamber or actuator and/or the pilot or bleed valve and/or a control lever or button or proximity sensor or switch. Alternatively, the operating or equilibrium valve may be mounted remotely with respect to the syphon assembly or chamber or actuator and/or the pilot or bleed valve and/or a control lever or button or proximity sensor or switch. In preferred embodiments, the pilot or bleed valve and/or a control lever or button or proximity sensor or switch is mounted or located remotely with respect to the syphon assembly or chamber or actuator, for example on an external and/or exposed surface of a cistern or toilet or water closet furniture or wall with or within which the syphon assembly is associated or comprised or incorporated. In such embodiments, the operating or equilibrium valve may be mounted to or adjacent to or otherwise associated with the syphon assembly or chamber or actuator or mounted remotely with respect thereto and/or adjacent to or remotely with respect to the pilot or bleed valve and/or control lever or button or proximity sensor or switch.

Activation or operation or opening of the operating valve or equilibrium valve preferably allows or permits fluid to drive the actuator, for example the prime mover or piston thereof, e.g. to move the piston rod, for example to move the piston within the chamber to initiate a syphonic flushing action. The control lever or button or proximity sensor or switch preferably comprises or is incorporated within an activator or flush activator or push button or an integrated activator or flush activator or push button, which may be configured to provide partial flush and/or dual flush functionality, for example the activator or flush activator or push button may allow either full or partial flush actuation or activation. In some embodiments, a partial flush is initiated by activating or pressing and holding the push button, while a full flush is initiated by activating or pressing and releasing the push button, or vice versa.

In some embodiments, the activator or flush activator comprises a valve means operatively connected or connectable to the or an equilibrium valve, for example a bleed port of the or an equilibrium valve, e.g. for selectively opening and/or closing, or wherein the equilibrium valve is configured or adapted to selectively open and/or close, fluid communication between the actuator and the or a source of fluid or pressurised fluid. The activator or flush activator may additionally or alternatively comprise an actuator, e.g. for operating the valve means. In some embodiments, the activator or flush activator comprises an inlet, which may be operatively or fluidly connected or connectable to a bleed port of the equilibrium valve, and/or an outlet, which may open to or into, and/or be configured or arranged to feed into, a cistern to which the siphon assembly is incorporate or connected in use.

Another aspect of the invention comprises a control valve assembly, e.g. for operating or controlling a flushing system or assembly or syphon assembly, for example as described above, the control valve assembly comprising an operating or equilibrium valve, e.g. fluidly connected or connectable to the or a syphon assembly, and/or a activator or flush activator, which may comprise an outset and/or an inlet. The activator or flush activator or the outlet thereof may be operatively connected to the operating or equilibrium valve or to a bleed port thereof. The activator or flush activator may be operable to open, in use, fluid communication between the inlet and the outlet, e.g. thereby causing the equilibrium valve to open, for example to supply fluid, e.g. under pressure, to the syphon assembly or actuator thereof and/or to drive the syphon assembly or actuator to initiate a syphonic flushing action.

The operating or equilibrium valve may be fluidly connected or connectable to a flushing system or assembly. The activator or flush activator may be operable to open, in use, fluid communication between the inlet and the outlet, thereby causing the operating or equilibrium valve to open and supply fluid. e.g. under pressure, to the flushing system or assembly to initiate a flushing action.

Yet another aspect of the invention provides a activator or flush activator, e.g. for use in or with a control valve assembly or syphon assembly as described above, the activator comprising an outlet and/or an inlet, e.g. for fluidly connecting to an equilibrium valve or to a bleed port thereof, and/or an actuator and/or a valve member that may be operatively connected to the actuator and/or that may extend between the inlet and the outlet, wherein the actuator is operable to move, in use the valve member from a first position, for example in which fluid communication between the inlet and the outlet is prevented or inhibited, e.g. thereby causing the equilibrium valve to be in or move to a closed position or condition, to a second position, for example in which the inlet is in fluid communication with the outlet, e.g. thereby causing the equilibrium valve to open or to be in or move to an open position or condition.

The valve member may comprise a sealing means, for example an O-ring seal that may be received or receivable within a circumferential groove thereof, at one or each of its ends, for example wherein the or one of the sealing means is moved out of engagement with a passageway within which the valve member is at least partially received, e.g. when moved from the first position to the second position. The activator or flush activator may comprise a biasing means, for example a resilient biasing means such as a spring which may comprise compression spring, for or configured to bias the valve member toward the first position. The actuator may comprise a push button and/or may be connected or fixed to or with respect to e.g. threadedly connected or engaged to the valve member.

The assembly may comprise a partial flush means. The partial flush means may comprise a passage opening the syphon chamber to the interior of the cistern in use, which passage may be open when the piston is in an actuated or raised position or condition and/or closed when the piston is in a rest or lowermost position or condition or vice versa. The chamber may comprise the passage, which may at least partially surround the piston rod and/or may be closed by a sealing means or seal associated with the piston rod, for example as described in GB2329398. The sealing means may be biased to or toward a closed position or condition, for example in which the passage is closed. The assembly may be configured such that the sealing means is moved from the closed position or condition to an open position or condition only when the piston is at or adjacent a fully raised or uppermost position, e.g. such that a maximum volume flush can be effected by raising the piston and allowing it to drop to an intermediate position, for example below its fully raised or uppermost position, without delay, but a lesser volume flush can only be effected by holding the piston in a substantially fully raised or uppermost position until the water level drops below the passage opening allowing air to enter the chamber and interrupting the syphonic action

Another aspect of the invention provides a syphon assembly for discharging water from a cistern, the assembly comprising an inverted generally U shaped duct having an upleg and a downleg, an open-ended, e.g. enlarged, chamber fluidly connected to the upleg, a piston movable in the chamber for initiating a flushing action, a passage extending from the interior of the chamber to the interior of a cistern in use at a position that is higher than the open end of the chamber and a sealing means biased to a closed position or condition in which the passage is closed, wherein the assembly is configured such that the sealing means is moved from the closed position or condition to an open position or condition only when the piston is at or adjacent a fully raised or uppermost position, e.g. such that a maximum volume flush can be effected by raising the piston and allowing it to drop to an intermediate position, for example below its fully raised or uppermost position, without delay, but a lesser volume flush can only be effected by holding the piston in a substantially fully raised or uppermost position until the water level drops below the passage opening allowing air to enter the chamber and interrupting the syphonic action.

The sealing means may comprise a seal, e.g. a sealing washer, which may be biased or resiliently biased, for example by a biasing means or resiliently biasing means such as a spring which may be a compression spring. The sealing means may be biased or resiliently biased toward or against the chamber or passage or toward a closed or sealing position or condition. The passage may comprise an annular passage or vent, which may be interrupted. The or a piston rod or a lower portion thereof or the syphon piston may comprise an abutment surface or element or member, which may be configured to abut and/or unseat or move the sealing means, e.g. from the closed position or condition to the open position or condition. The sealing means may include an abutment surface or element or member that may be connected or mounted or fixed to the seal or sealing washer or formed integrally therewith.

Additionally or alternatively, the piston rod may comprise the passage. Additionally or alternatively, the passage may be defined between the piston rod and the opening through which the piston rod passes, for example by an undersized portion of the rod along part of its length or one or more depressions on an outer surface of the piston rod or through its centre.

The piston or syphon piston may comprise a plate or plate member or flat member and/or may incorporate one or more apertures or holes or openings, and/or a diaphragm, for example a flexible diaphragm that may be formed of a flexible e.g. elastic and/or plastics, material, which may be a sheet material. The diaphragm may coextend and/or may be secured, e.g. at its centre, to the plate or plate member or flat member, for example to on one of the major sides thereof. The assembly may further comprise a biaser or biasing means for biasing the piston or plate or plate member or flat member toward the open end of the chamber. The biasing means may comprise a weight that may be mounted, e.g. releasably or movably mounted, to the piston or plate or plate member or flat member. Additionally or alternatively, the biasing means may comprise a resilient biasing means, such as a spring, e.g. a compression spring, that may, for example, provide an urging force.

The actuator may be connected to the mains water supply or inlet valve or branch element or control valve or control valve means or assembly or operating or operating valve by a hose, for example a flexible hose. The connection between the actuator and the mains water supply or inlet valve or branch element or control valve or control valve means or assembly or operating or operating valve is preferably at the inlet of the actuator. The inlet of the actuator may be at or in a lower portion of the actuator and/or below the actuator piston or piston head in use, e.g. so that when water enters the cylinder portion it is forced upwards along with the piston in order to initiate a flush.

In use, operation of the control lever or button or proximity sensor or switch may activate the pilot or bleed valve or cause it to open, which may cause water to bleed from the pressure chamber of the equilibrium valve, e.g. through the tube and into the cistern. A subsequent reduction in the pressure in the equilibrium valve, e.g. in the internal pressure chamber thereof, may result in the equilibrium valve opening, for example allowing water to flow into the piston chamber, driving the piston and plate member up to start the syphonic effect. Removal of the activation of, or force on, the control lever or button or proximity sensor or switch may cause the equilibrium valve to close and/or the biasing means to cause the plate or plate member or flat member to return to a pre-flush position or condition. As the piston returns to its pre-flush position or condition, water in the piston cylinder may bleed out around the actuator piston or piston head.

The syphon assembly may comprise an adjustment means for adjusting the configuration of the syphon in the manner described in GB2486776, the entire contents of which are incorporated herein by reference. The syphon may further comprise an adaptable full flush volume feature, which may be similar to the arrangement disclosed in GB2338723, the entire contents of which are incorporated herein by reference. Alternatively, the syphon may comprise an adaptable full flush volume feature that is adjustable with the syphon in situ. For example the syphon assembly may comprise a closure element for selectively changing the full flush volume or the level at which syphonic action is interrupted, which closure element may be removable when the syphon assembly is mounted, in use, within a cistern.

Another aspect of the invention provides a syphon assembly for discharging water from a cistern, the assembly comprising an inverted generally U shaped duct having an upleg and a downleg, an open-ended, e.g. enlarged, chamber fluidly connected to the upleg, a piston movable in the chamber for initiating a syphonic flushing action and a closure element mounted, e.g. removably and/or slidably mounted, to a side wall of the chamber to cover an aperture therein, wherein the closure element is removable from above when the syphon assembly is mounted, in use, within a cistern.

The closure element may be received, for example slidingly or slidably received, within a slot or guide in or on or associated with the chamber or the side wall thereof. Preferably, the closure element is slidable along, e.g. vertically along, the chamber or side wall such that it may be removed from above. The closure element may comprise a stop or stop element, such as a flange, which may be comprised or incorporated in or mounted on an upper portion of the closure element, for example which flange may abut, e.g. in use, a portion or surface, e.g. an upper portion or surface, of the slot or guide or chamber or side wall. The closure element may additionally or alternatively comprise one or more, e.g. two or more, preferably three or more, such as four or five or more, openings or apertures or holes each of which may correspond to or define a different full flush volume or water level at which syphonic action is or would be interrupted. One or more or each of the openings or apertures or holes may comprise a closure or plug that may be received, e.g. removably received, therein and/or secured thereto or with respect thereto, for example to close the opening or aperture or hole.

The syphon assembly or chamber may comprise one or more, preferably two or more, such as three or four or five or more, e.g. a plurality of, ribs, which may be horizontal. The slot or guide may be at least partially provided by or incorporated within the or at least one of the or each of the ribs. The or at least one of the or each of the ribs may extend horizontally and/or include a cutout that at least partially defines the slot or guide. The Or each cutout may include an enlarged portion, e.g. central portion, for example to permit the closure or plug or closures or plugs of the closure element to pass therethrough.

The syphon assembly may be constructed from any suitable material or combination of materials. Preferably, the toilet flushing means is constructed from a corrosion-resistant material, for example a plastics material, or a corrosion resistant metal such as copper.

A more general aspect of the invention provides a draining apparatus for discharging water from a cistern, the apparatus comprising an inlet member, an outlet member fluidly connected to an inlet of the inlet member by a conduit, and a piston assembly connectable to a mains water supply, wherein, in use, the piston assembly can be actuated by mains pressure water, thereby causing flow of water through the inlet and discharging water from the cistern.

A further aspect of the invention provide a kit of parts for assembly into an assembly as described above and/or a retrofit kit for adapting an existing syphon assembly to provide an assembly as described above and/or a cistern comprising a syphon assembly and/or any one or more assemblies or components described above. A yet further aspect of the invention provides a method of discharging water from a cistern, for example using a syphon assembly described above, the method comprising one or more of the steps described above or that the skilled person would understand to be advantageous.

Referring toFIGS. 1 and 2there is shown a syphon assembly1for discharging water from a cistern (not shown). In this embodiment, the syphon assembly1includes an adjustment means10for adjusting the configuration of the syphon. The syphon assembly1includes an inverted generally U shaped duct11fluidly and telescopically connected to an upleg2and a downleg3, an enlarged rectangular chamber4integral with the upleg2and having an open lower end40, a piston5movable in the chamber4and a hydraulic actuator6connected to the piston5by a piston rod7that extends through a hole41in an upper wall of the chamber4. The downleg3is connected, in use, to the flush pipe of a cistern (not shown) to feed flush water into a toilet pan (not shown). The hydraulic actuator6is operable to move the piston5within the chamber4to initiate a syphonic flushing action in use.

The adjustment means10is provided by a releasable fastener12that secures the U shaped duct11, the upleg2and the downleg3together by engaging simultaneously a respective chain of lugs13in the manner described in GB2486776.

In this embodiment, the chamber4includes an adaptable flush volume feature42similar to the arrangement disclosed in GB2338723. More specifically, one of the wider, side walls of the chamber4is provided with a vertically extending venting aperture in the form of a generally rectangular slot43closed at its upper end, open at its lower end and having a raised bridging portion44across the lower end. The slot43also includes an edge profile that slidably receives and releasably and sealingly engages a correspondingly shaped closure element45. The closure element45includes two removable plugs46for varying the flush volume, a lower flange47and a pair of locking lugs48. The closure element45is inserted into and/or removed from the slot43through the open lower end and is secured in place by captivating the bridging portion44of the chamber4between the flange47and locking lugs48.

The piston5includes a plate50with a coextensive diaphragm51and a weight52each of which is secured at its centre to the centre of the upper major surface of the plate50. The plate50is formed of a rigid or semi-rigid plastics material in this embodiment and incorporates a plurality of apertures52through its thickness and a central engaging hole53with a counterbore on the opposite side of the piston5to the diaphragm51and weight52. The diaphragm51is formed of a sheet of flexible plastics material in this embodiment such that a flow of water from beneath the piston5through the apertures52causes the diaphragm51to raise and allow water to flow, but prevents flow in the opposite direction, thereby operating as a one-way valve.

The actuator6includes an actuator piston60reciprocable within an actuator cylinder61. The actuator piston60includes a threaded hole62for securement with an upper end of the piston rod7and the piston rod7extends through a first end of the actuator cylinder61. The actuator cylinder61includes a radial inlet63adjacent its first end and four peripheral vents or slots64adjacent a second end thereof. The actuator cylinder61also includes an anti-splash cap65, which covers the second end and surrounds the peripheral vents or slots64, but is spaced therefrom to provide a gap for water and/or air to pass. The inlet63is connected to an equilibrium valve (not shown) by a flexible hose66.

In this embodiment, the actuator piston60is sized and dimensioned such that a fluid flow entering the actuator cylinder61from the inlet63forces the actuator piston60from the first end of the actuator cylinder61toward the second end thereof. The actuator piston60is also sized and dimensioned such that the clearance between the actuator piston60and the cylinder61permits some fluid to flow therebetween. In this embodiment, the piston60is formed of a plastics material having a relatively low weight.

The piston rod7is substantially cylindrical in shape with an undersized first portion70, which is an upper portion in this embodiment, and a second portion71, which is a lower portion in this embodiment. In this embodiment, the first portion70is sized and dimensioned to provide clearance between the hole41in the chamber4to allow air to pass therebetween, while the second portion71is sized and dimensioned to prevent the passage of air when received within the hole41. The piston rod7also includes a threaded end72at the end of the first portion70and an engaging head73at the end of the second portion71. The threaded end72is received within and engages the threaded hole62of the actuator piston60to secure the piston rod7to the actuator piston60. The engaging head73is an enlarged portion that is received within the correspondingly shaped engaging hole53of the piston plate50.

The supply of mains water is controlled by a control assembly that includes the equilibrium valve (not shown), which is fluidly connected to a flush activator8that incorporates a bleed valve80operated by an integral a pushbutton81(shown inFIGS. 3 to 5). The bleed valve80includes an inlet housing82, an outlet housing83and a valve member84. The flush activator8also includes a push fit fitting85for securely receiving a tube85a, a compression spring87and a circular mounting flange86with an internally threaded hollow body86awith a hexagonal circumference86b.

The pushbutton81includes a body81awith an internally threaded blind hole81bextending from a first end thereof and an enlarged head81cat a second end thereof. The head81cincludes a convex actuation surface81don a first side thereof and an annular recess81eon a second side thereof.

The inlet housing82is hollow and substantially cylindrical with a longitudinal bore that narrows at its centre to provide an inlet port82a. The push fit fitting85is securedly received within a first end82bof the inlet housing82by an interference fit with an O-ring seal85bcaptivated between the push fit fitting85and an adjacent internal surface of the inlet housing82. The inlet housing82also includes an internally threaded second end82c.

The outlet housing83is also hollow and substantially cylindrical with four radial outlets83afluidly connected to and extending from a longitudinal bore83a′, which receives and guides the valve member84. The outlet housing83includes an undersized, externally threaded first end83bfor threaded engagement with the second end82cof the inlet housing82and an O-ring seal83creceived within a circumferential groove to provide a sealing engagement therebetween. The outlet housing83also includes a flange83dat a second end thereof and an external thread83ebetween the outlets83aand the flange83dfor engagement with the mounting flange86in order to captivate a wall portion (not shown) of a cistern (not shown) or water closet furniture (not shown) therebetween in the normal way.

The valve member84includes a first, tapered end84a, a snap ring84breceived within a first circumferential groove84cadjacent the first end84a, a first O-ring seal84dreceived within a second circumferential groove84e, a second O-ring seal84freceived within a third circumferential groove84gand a second, externally threaded end84hfor engagement with the blind hole81dof the pushbutton81. The valve member84also includes a circumferential undercut84ibetween the O-ring seals84d,84f.

As shown more clearly inFIG. 5, the compression spring87is located around the valve member84and pushbutton body81awith one of its ends received within the annular81eof the pushbutton81. The compression spring87is captivated between the pushbutton head81cand an internal annular recess83fof the outlet housing83and biases the valve member84toward a closed position in which the snap ring84babuts the first end83bof the outlet housing83. With the valve member84in the closed position, the first O-ring seal84dseals against the bore83a′ of the outlet housing83to close fluid communication between the inlet port82aand the outlets83a.

Depression of the pushbutton81moves the valve member84from the position illustrated inFIG. 5to that shown inFIG. 6, which moves the O-ring seal84dout of engagement with the bore83a′, thereby allowing pressurised water from the bleed port of the equilibrium valve (not shown) to exit through the outlets83avia the undercut84i. This releases pressure from a pressure chamber of the equilibrium valve (not shown), thereby opening the equilibrium valve (not shown).

The equilibrium valve (now shown) in this embodiment mounted remotely from the syphon assembly1and is fluidly connected to a domestic mains water system (not shown) via a fill valve assembly9,109to selectively provide a flow of water at mains pressure to the actuator cylinder61through the inlet63. The use of a bottom entry fill valve assembly9or a side entry fill valve assembly109depends upon the cistern (not shown) into which the syphon assembly1is incorporated in use.

As shown in7to9, the bottom entry fill valve assembly9includes a float controlled diaphragm valve90of the kind described in GB2332731, the contents of which are incorporated herein by reference, in which water pressure on opposite sides of the diaphragm is kept substantially in equilibrium so that when a lever mounted float91drops, a bleed aperture is exposed and unseats the diaphragm by a small change in pressure differential. The fill valve assembly9according to this embodiment differs from the aforementioned design in that there is provided a branch element92that cooperates with the valve90to feed the actuator6of the syphon assembly1. Specifically, the filter chamber90athat houses the conical inlet filter90bof the valve90, which is fed by the vertical feed pipe90c, includes a pair of side openings90d,90ein addition to the upper outlet90fextending horizontally from the filter chamber90a, wherein the branch element92is receivable in either one of the openings90d,90eand secured to the valve90by a clamp element93.

The branch element92in this embodiment includes a twin barrel housing94with an open end94a, a first side that includes an undersized inlet spigot95opposite the open end94aand feeding into an inlet chamber96and a second side that includes a filter chamber97feeding into a radial outlet98extending perpendicularly from the filter chamber97. The inlet spigot95includes an inlet passage95athat feeds into a the inlet chamber96, which is open at the open end94aof the housing94. The filter chamber97is also open at the open end94aof the housing94. The branch element further includes a closure element99for closing the open end94aof the housing94, which has a facing internal surface shaped to provide fluid communication between the open ends of the inlet chamber96and the filter chamber97.

The inlet spigot95includes an outer circumferential groove95bthat receives an O-ring seal95cand an external circumferential securing flange95d. The inlet chamber96receives pair of non-return valves96a,96bto prevent backflow and having respective O-ring seals, the non-return valves96a,96bbeing separated by a spacer96creceived and captivated therebetween to enable independent operation.

The filter chamber97extends parallel with respect to the inlet chamber96and is also open at the same end of the housing94, but it includes a hemispherical base97aand feeds into the outlet98radially. The filter chamber97houses a conical inlet filter97b.

The outlet98is hollow and substantially cylindrical in shape with two steps, providing three internal diameters, wherein a push fit fitting98ais received within the largest diameter, free end of the outlet portion98and abuts one of the steps, while an O-ring seal98bis received within the intermediate diameter and abuts a second of the steps for sealing with a tube98cthat is received within the smallest diameter and feeds the inlet of the equilibrium valve (not shown).

The closure element99includes a pair of inwardly extending flanges99athat cooperate with a pair of opposed external flanges94bprojecting outwardly from the open end94aof the housing94to secure the closure element99to the housing94and to seal the open end94athereof. The closure element99also includes an O-ring seal99breceived within a circumferential groove of a spigot portion99cthereof, which O-ring seal99bsealingly cooperates with an internal surface of the second end of the housing94.

The clamp element93is shaped to match the contours of the portion of the valve90that houses the valve filter chamber90a, but also includes inwardly extending radial flanges93aadjacent the openings90d,90efor cooperation with the securing flange95dof the inlet spigot95. Each radial flange93aextends inwardly from a respective hollow, part cylindrical portion93bof the clamp element93, circumscribes more than 180° to provide a C-shaped receptacle and includes a lead-in to facilitate insertion. In use, one of the C-shaped receptacles receives by a snap fit the portion of the inlet spigot95between the securing flange95dand the outer surface of the inlet chamber96of the housing94such that the flange93ais captivated therebetween.

The branch element92in this embodiment is reversible in that it may be inserted into either of the valve openings90d,90edepending upon the space constraints within the cistern (not shown). The fill valve assembly9also includes a plug93cfor closing off the unused opening90d,90e, which cooperates with the other of the C-shaped receptacles of the clamp element93. The plug93cincludes similar features to the spigot portion95, namely an outer circumferential groove93dthat receives an O-ring seal93e, an external circumferential securing flange93fand an oversized head93gbetween which flange93fand head93gis received the other flange93aof the clamp element93to seal off the other of the valve openings90d,90e.

Turning now toFIGS. 10 to 13, the side entry fill valve assembly109is similar to the bottom entry fill valve assembly9, wherein like references depict like features that will not be described further. The side entry fill valve assembly109differs from the bottom entry fill valve assembly9in that the vertical feed pipe90cis replaced with a threaded extension190cof the filter chamber housing190a, the side openings190d,190ethereof are recessed within the valve190and are in fluid communication with one another via an annular recess190fand the inlet spigot95is replaced with an annular inlet member195of the branch element192. The valve190also includes a pair of O-rings190geach received within a respective groove190hon either side of the annular recess190f.

The annular inlet member195includes a cylindrical body195awith a radial passageway195bthat feeds into the inlet chamber96and a square flange195cwith a square shaped recess195dfor receiving a correspondingly shaped locating flange190fof the valve190. The side entry fill valve assembly109also includes a pair of locking nuts193a,193bfor securing the annular inlet member195to the valve190such that it is aligned with the side openings190d,190e. The branch element192in this embodiment is also reversible by rotating it through 180 degrees prior to locating the flange190fof the valve190ainto the recess195dof the branch element195and securing them together with the locking nuts193a,193b.

In use, when a user depresses the pushbutton81, the equilibrium valve (not shown) opens, fluid flows into the cylinder61through the inlet63, driving the actuator piston60upward, pulling the piston rod7to drive the piston5upward within the chamber4to initiate a syphonic flushing action. In this embodiment, a full flush may be initiated by pressing and holding the push button81so that the equilibrium valve (not shown) stays open, thereby ensuring that the second, lower portion71of the piston rod7closes the hole41in the chamber4. The flushing action continues until the water level reaches the base of the chamber4, at which point the syphonic effect is broken and the cistern (not shown) refills in the known manner by the float operated fill valve9,109. A partial flush may be initiated by pressing and releasing the push button81so that the equilibrium valve (not shown) closes after the flush is initiated, with the weight52forcing the piston5downward such that the first portion70of the piston rod50fits loosely within the hole41of the chamber4, thereby providing a vertical passage therebetween to break the siphonic action when the water level drops below the hole41.

Clearly, the reverse of the partial flush arrangement described above is also envisaged. This may be achieved, for example, by configuring the syphon assembly1as described in GB2329398, the entire contents of which are incorporated herein by reference.

Turning now toFIG. 14, there is shown a syphon assembly100according to a second embodiment, which is similar to the syphon assembly1according to the first embodiment, wherein like references depict like features that will not be described further. The syphon assembly100according to this embodiment differs from that of the first embodiment in that the equilibrium valve101is mounted directly to the hydraulic actuator6, the means by which a partial flush is achieved has been reconfigured, the weight52is incorporated within the actuator piston160and piston rod107and the adaptable flush volume feature142has been reconfigured for improved access and strength.

The equilibrium valve101in this embodiment functions in a manner that is similar in principle to the diaphragm valves90,190of the fill valve assemblies9,109described above. Specifically, the equilibrium valve101includes a diaphragm110with a peripheral flange111captivated between opposed housing portions112a,112b, a central valve portion113with a central hole incorporating a flow regulation pin114and a flexible bridging portion115joining the peripheral flange111to the valve portion113. As shown inFIGS. 14 and 15, the downstream side of the diaphragm110has a larger surface area exposed to fluid pressure than the upstream side thereof. The upstream housing portion112aincludes a valve seat112cand a plurality of radial outlets112dfluidly connected to the inlet63of the actuator6. The downstream housing portion112bincludes a central outlet112ethat feeds the tube85aconnected to the flush activator8at one end and to a push fit fitting112fmounted to the actuator6at the other end. The mains water inlet tube98cis connected to the equilibrium valve101by a push fit fitting116.

In use and with the activator8in the position shown inFIGS. 5 and 15, water pressure on opposite sides of the diaphragm110is kept substantially in equilibrium, which causes the valve portion113of the diaphragm110to be biased against the valve seat112con the upstream housing portion112a. When the pushbutton81of the activator8is depressed, the passage between the outlet112eof the downstream housing portion112band the radial outlets83aof the activator8is open, which reduces the pressure on the downstream side of the diaphragm110, owing to the restricted flow of pressurised water passed the flow regulation pin114. This in turn, unseats the diaphragm110and opens fluid flow between the mains water inlet tube98cand the radial outlets112dof the equilibrium valve101and drives the piston160to raise the piston rod107in order to initiate the flush.

The piston rod107in this embodiment has a constant diameter and is received within a spigot152connected to the syphon piston5. An interrupted annular vent141surrounds the hole41in this embodiment, which vent141provides a vertical passageway joining the interior of the chamber104of the syphon assembly100to the inside of the cistern (not shown). The syphon assembly100includes a sealing element171in the form of a washer172with a hollow, cylindrical portion173depending therefrom and compression spring174all surrounding the piston rod107. The washer172and spring174are captivated between the base of the actuator cylinder61and the top of the vent141such that the spring174urges the washer172against the top of the chamber104to seal the vent141.

In use, when the piston rod107is raised to its uppermost position, the spigot152urges the cylindrical portion173, raising sealing washer172against the bias of the spring174, thereby exposing the vent141. If the pushbutton81is held in a depressed position as shown inFIG. 6, the flush continues until the water level reaches the vent141, at which point the syphonic action is interrupted to provide a partial flush. If the pushbutton81is depressed and released, the syphon piston5drops as the water in the actuator cylinder61flows around the piston160and the sealing washer172is urged against the vent141under the influence of the biasing spring174. The use of a compression spring174is particularly advantageous because it ensures that the vent141is sealed before the water level drops to the level of the vent141, which could inadvertently result in a partial flush where a full flush is requested. In this embodiment, the piston160and rod107are both formed of a heavier material than that of the first embodiment, for example a brass material, in order to obviate the need for a separate weight52as in the syphon assembly1according to the first embodiment.

The adaptable flush volume feature142in this embodiment is incorporated with the outer, short side140of the chamber104, as shown more clearly inFIGS. 19 and 20. In this embodiment, chamber104includes a plurality of horizontal reinforcing ribs141spaced vertically along its height. The chamber104includes an elongate opening143extending vertically with an open bottom and a closed top similar to the slot43of the syphon1of the first embodiment. However, engagement between the opening143and the closure element145in this embodiment is provided by respective cutouts141ain each reinforcing rib141extending through its thickness on the side thereof adjacent the opening143, thereby providing an interrupted vertical slot that is open at its upper end.

Each cutout141ais substantially rectangular with an enlarged central portion to permit the removable plugs146of the closure element to pass therethrough. In this embodiment, there is provision for up to five removable plugs146only four of which are shown. The closure element145includes an upper flange147with a curved recess147a, wherein the outer portions of the flange147abut the region of the uppermost reinforcing rib141surrounding the cutout141awhen the closure element145is received therein in order to hold it in place. Thus, the closure element145can be removed from above by simply placing a finger within the recess147aand lifting the closure element145, which is particularly advantageous as this can be done with the syphon100located in situ within the cistern (not shown).

It will be appreciated by those skilled in the art that several variations are envisaged without departing from the scope of the invention. For example, the hydraulic actuator6may be replaced with a pneumatic, electromagnetic or any other power-driven actuator. Accordingly, the source of power that drives the actuator may be provided by any other suitable means. Furthermore, the weight52may be replaced by any suitable biasing means, such as a spring or other such arrangement. The partial flush means need not be provided by an undersized portion of the piston rod7or even a vertical passage as described. Any other partial flush means may be provided. The syphon assembly1need not include an adjustment means10or may incorporate some other adjustment means.

It will be appreciated by those skilled in the art that any number of combinations of the aforementioned features and/or those shown in the appended drawings provide clear advantages over the prior art and are therefore within the scope of the invention described herein.