WO2007071945A2

WO2007071945A2 - Float valve

Info

Publication number: WO2007071945A2
Application number: PCT/GB2006/004715
Authority: WO
Inventors: Robert George
Original assignee: Robert George
Priority date: 2005-12-22
Filing date: 2006-12-15
Publication date: 2007-06-28
Also published as: GB0526266D0; GB2433544A; GB2433544B; WO2007071945A3

Abstract

An apparatus for providing a seamless supply of fluid from a first exhaustible fluid supply and a second fluid supply is described, said apparatus comprising: a switching vessel having at least one first inlet for receiving fluid from the first exhaustible fluid supply and at least one second inlet for receiving fluid from the second fluid supply and at least one fluid outlet; and a regulating mechanism arranged to provide fluid from said first exhaustible supply for output at said at least one fluid outlet whilst said first exhaustible supply is not exhausted, and fluid from said second fluid supply when said first exhaustible fluid supply becomes exhausted; the apparatus being further provided with means arranged such that fluid is retained substantially within said first exhaustible fluid supply and said second fluid supply when fluid is not required from said at least one outlet. A helical float valve arrangement for use with such an apparatus is also described.

Description

Float Valve

Technical Field

The present invention relates to a float valve for use in a liquid containing vessel.

Additionally, other aspects of the invention provide an apparatus for providing seamless fluid supply from multiple sources, as well as a switching valve.

Background to the Invention, and Prior Art

There is an increasing need to reduce domestic demand for potable water from mains water sources, and at the same time to relieve problems caused by the volume of waste discharged to sewers. One way to reduce the amount of waste is to provide techniques for recycling so called "grey water", being waste water which is generated from a sanitary appliance such as a bath, basin, or sink, and which is suitable for appropriate recycling purposes.

One known use for the recycling of grey water is to provide an intermediate storage tank into which grey water is exhausted from the sanitary appliances in which it is produced. The grey water then stored in the intermediate storage tank has, in the past, been used primarily for irrigation purposes, for the following reason.

"Grey" water is typically only generated when the primary appliance in which it is produced, such as a bath, basin, sink, or the like is used, and thus the supply of grey water generated by one or more such primary appliances is intermittent. It would be possible for other household appliances, such as dishwashers or washing machines to "use such grey water in place of the usual clean water, but for such secondary appliances to fully operate they must conventionally be provided with two water supplies, one for grey water and one for clean water. This adds expense, complication, and in the case of existing installations, considerable disruption. Moreover, there must be a mechanism provided within each appliance to allow for switching within the two supplies when the grey water supply is exhausted, and with such switching there is the risk that the operation of the secondary appliance such as the dishwasher or washing machine will be impaired if the switching does not take place immediately upon the grey water supply being exhausted. Moreover, if the switching function is itself impaired, then further damage may result to the secondary appliance through failure of the water supply. i Summary of the Invention

To address the above problems the present invention provides from one aspect an apparatus which provides for a seamless switchover from a first exhaustible fluid supply and a second, main, supply. In particular, the apparatus provides for priority to be given to fluid in the exhaustible supply, such that that fluid is then used first, but then once it is exhausted a seamless switchover from the exhaustible supply to the main supply is performed, and which switchover is transparent to any appliance, device, or process which is making use of the fluid supply. This is achieved by providing an apparatus having a switching vessel into which both the exhaustible supply and the main supply are provided, the vessel having a regulating mechanism which effectively keeps track of the supply from the exhaustible supply, and automatically performs a seamless handover to the main supply in the case of the exhaustible supply running out, or not being able to otherwise supply the required volume of fluid. The apparatus is particularly suitable for use in solving the "grey water" problem noted above, but it should be noted that the apparatus is not limited for such use, and can be used in any situation where fluid can be supplied out of a first, exhaustible, supply, and a second, mains, supply. In order to render the switching mechanism compact and reliable, a helical float valve arrangement is also provided. From a first aspect the present invention provides a float valve for use in a liquid containing vessel, comprising a float and a rotary part, one of said float or said rotary part having a helical element and the other of said float or said rotary part having a helical element engaging part arranged in use to engage with the helical element whereby to cause a rotary motion as said float moves with the liquid levels in the vessel, the valve further comprising a valve head arrangement operable in response to said rotary motion.

With such an arrangement a compact and reliable valve arrangement can be provided, and which can find application in situations where space constraints mean that conventional float arm valves cannot be used.

Preferably said valve head arrangement further comprises a valve head and a valve seat, the rotary part being subject to said rotary motion and being further arranged to act on said valve head to move the head into the valve seat. Even more preferably said rotary part and said valve head have corresponding helical mating surfaces, whereby the rotary motion of said rotary part is translated into a linear motion of said valve head into the valve seat. Such features aid in the provision of a compact and reliable valve operation. With such an arrangement preferably the respective pitches of said helical mating surfaces of said rotary part and said valve head and said helical groove are arranged so as to obtain a mechanical force advantage from the movement of said float. Such a feature ensures that the valve can be seated with sufficient force to ensure that the valve is closed against the fluid supply.

In the preferred embodiment said float is provided with said helical groove and said rotary part comprises a sleeve having at least one lug arranged to fit into the helical groove on said float, said float being arranged substantially concentric with said sleeve whereby motion of said float in said vessel causes rotary motion of said sleeve. Moreover, an input port to said valve comprises an input pipe through which said liquid flows, said input pipe being arranged within said sleeve axially parallel thereto, said input pipe being terminated with said valve head arrangement. Such features again contribute to the compactness of the valve.

Another aspect described in the present specification relates to an apparatus for providing a seamless supply of fluid from a first exhaustible fluid supply and a second fluid supply, said apparatus comprising: a switching vessel having at least one first inlet for receiving fluid from the first exhaustible fluid supply and at least one second inlet for receiving fluid from the second fluid supply and at least one fluid outlet; and a regulating mechanism arranged to provide fluid from said first exhaustible supply for output at said at least one fluid outlet whilst said first exhaustible supply is not exhausted, and fluid from said second fluid supply when said first exhaustible fluid supply becomes exhausted; the apparatus being further provided with means arranged such that fluid is retained substantially within said first exhaustible fluid supply and said second fluid supply when fluid is not required from said at least one outlet.

Using such an apparatus then priority can be given to supplying fluid from the first exhaustible supply whilst that supply is available, but with a seamless handover occurring to providing fluid from the second supply when the first supply becomes exhausted. Thus, any appliances or processes which require a seamless supply of fluid for their operation can be supplied using such an apparatus. Moreover the provision of the means providing for fluid to be retained in the supplies themselves means that the apparatus does not need to act unnecessarily as a storage container, as the fluid is retained in the actual supplies. In this respect, the supplies include any pipework or the like which connects the supplies to the switching vessel.

Preferably said means comprise said switching vessel being a sealed vessel, although in an alternative embodiment said means may comprise a second regulating mechanism arranged to regulate said at least one first inlet to allow fluid into said vessel from said first exhaustible fluid supply as fluid is drawn from said at least one fluid outlet. Whichever option is chosen means that the apparatus need not store excess fluid therein.

In a preferred embodiment said regulating mechanism comprises an inlet regulator arranged to regulate said at least one second inlet to allow fluid into said switching vessel from said second fluid supply when said first exhaustible fluid supply becomes exhausted, whereby said fluid within said vessel is available for output at said at least one fluid output. Regulating said second inlet provides for priority to be given to fluid from said first, exhaustible, supply.

Moreover, in the preferred arrangement said fluid is a liquid, and said regulating mechanism comprises a float valve, said vessel being adapted to buffer an amount of said liquid, and said float valve operating to permit fluid entry through said at least one second inlet when the level of liquid in said vessel falls below said amount. Preferably said float valve comprises a float and a rotary part, one of said float or said rotary part having a helical element and the other of said float or said rotary part having a helical element engaging part thereon arranged in use to engage with the helical element whereby to cause a rotary motion as said float moves with the liquid levels in the vessel, said regulating mechanism being further arranged so as to be operable in response to said rotary motion. Such an arrangement provides for a compact and reliable operation.

The float valve preferably further comprises a valve head and a valve seat, the rotary part being subject to said rotary motion to act on said valve head to move the head into the valve seat. More preferably the rotary part and the valve head have corresponding helical mating surfaces, whereby the rotary motion of said rotary part is translated into a linear motion of said valve head into the valve seat. With such an arrangement the motion of the float as the liquid level moves up and down is translated into a closing and opening of the valve, and hence the valve becomes self-regulating: as more liquid enters the vessel the float rises and the valve is closed, whereas as liquid leaves the vessel the float falls and the valve is opened. More preferably the respective pitches of said helical mating surfaces of said rotary part and said valve head and said helical groove are arranged so as to obtain a mechanical force advantage from the movement of said float. This ensures that the valve can be closed against what may be a relatively high pressure supply through the second inlet. In the preferred embodiment said float is provided with said helical groove as said helical element and said rotary part comprises a sleeve having at least one lug arranged to fit into the helical groove on said float, said float being arranged substantially concentric with said sleeve whereby motion of said float in said vessel causes rotary motion of said sleeve. More preferably said second inlet comprises a first pipe, said sleeve being arranged substantially concentric with said pipe. Such features aid in providing a compact and reliable construction.

Preferably said vessel comprises a manifold portion having said inlets and said at least one outlet therein, and a sidewall portion, said sidewall portion being removable from said manifold portion. Such a feature allows the vessel to removed for cleaning leaving the manifold with any pipework connected behind.

Preferably a filter for filtering fluid is provided. Preferably the filter is located at or before the inlet from the exhaustible supply, but may equally, in alternative embodiments, be located at or from the outlet. This is especially advantageous where one of the fluid supplies may be supplying contaminated or dirty fluid.

A preferred embodiment of the invention includes a switching valve having at least a first input port connected to said second fluid supply, and a second input port connected to said at least one fluid outlet, and at least a first output port, the valve being arranged to be switchable from a first state wherein fluid is able to pass from said second input port to said first output port, and a second state wherein fluid from said first input port is able to pass to said first output port. Such a feature allows the apparatus to be switched in and out of the fluid circuit, such that, for example, fluid may be supplied instead from the second fluid source all the time. Moreover, however, preferably said switching valve further comprises a second output port connected to said at least one second fluid inlet, wherein in said first state fluid is able to pass from said first input port to said second output port. Such a valve allows the apparatus not only to be switched in and out as above, but the same valve can also be used to simultaneously isolate the apparatus from the second supply, such that the apparatus can be removed, for example for cleaning.

The apparatus is particularly, although not exclusively, envisaged as being used where the fluid is liquid, and in particular where the first exhaustible fluid supply is at least one supply of "grey" water, and the second fluid supply is a mains water supply, hi this respect, "grey" water refers to waste water typically generated from a sanitary appliance and which is appropriate for recycling purposes. Such water would be water which, although not clean, would not be hazardous to human health (i.e. would not be classed as sewage), and which is otherwise fit for the purpose to which it is intended to be put. For example, waste water from baths, sinks, and showers would be termed "grey" water, although it should be noted that this is a non-exhaustive list, and other appliances which provide water as a waste by-product may also be envisaged, such as de-humidifiers, condenser dryers, or air-conditioning systems.

In view of the above, from another aspect the present invention also provides a system comprising: one or more first appliances which in use produce waste "grey" water; an apparatus as described above; a mains water supply; and one or more second appliances which in use may use "grey" water; outlets of the first appliances being connected to the at least one first inlet, the mains water supply being connected to the at least one second inlet, and inlets of the second appliances being connected to the at least one outlet. Preferably, such a system is incorporated within a building. The present specification also describes another aspect of the invention, being a switching valve comprising a valve body of substantially circular cross-section and a divider plate rotatably mounted co-axially with the valve body and extending from one side of an interior volume of the valve body to the other whereby to divide said .interior volume into at least two sub-volumes, the valve body having at least first, second, and third ports disposed around the valve body, the disposal of said ports being such that when said divider plate is in a first position the first port and the second port open into the same sub-volume, and in a second position of said divider plate the second port and the third port open into the same sub-volume. Such a valve construction allows for a reliable construction providing for easy switching between ports.

Preferably the valve body further has a fourth port disposed therein at a position such that when said divider plate is in a first position the first port and the second port open into the same one of the sub-volumes and the third port and fourth port open into another one of the sub-volumes, and in a second position of said divider plate the second port and the third port open into the same one of the sub-volumes and the first port and fourth port open into another one of the sub-volumes. Preferably the ports are equiangularly disposed around the valve body. Brief Description of the Drawings

Further features and advantages of the present invention will become apparent from the following description of embodiments thereof, presented by way of example only, and by reference to the accompanying drawings, wherein like reference numerals refer to like parts, and wherein: -

Figure 1 is a system block diagram illustrating an overall system in which embodiments of the present invention may be used;

Figure 2 is a vertical cross section of an apparatus according to a first embodiment of the present invention;

Figure 3 is a horizontal cross section of the apparatus of the first embodiment for the present invention;

Figure 4 is a cross section of a valve forming another embodiment of another aspect of the present invention; and Figure 5 is a cross section the same as Figure 4, but showing an operating part of the valve in a different position.

Description of the Embodiments

Figure 1 is a system diagram illustrating how an apparatus according to the first embodiment of the invention may be employed. In particular, within the first embodiment of the invention to be described, the apparatus of the first embodiment of present invention is employed to provide a seamless supply of water from a plurality of grey water producing appliances, as well as from the mains supply, to a plurality of secondary appliances, which may use the grey water supplied thereto. More particularly, with reference to Figure 1, a central handover device 10 is provided, having a first input port to which pipe 20 is connected, and a second input port to which pipe 18 is connected. A first output port is connected via pipe 22 to secondary appliances 24 and 26, being in this example a washing machine, and dishwasher respectively. The first input port is connected by pipe 20 to a plurality of grey water producing appliances, such as bath 12, shower 14, and sink 15. It should be noted that as many grey water appliances as are desired can be connected to the pipe 20, but that not all grey water producing appliances need be plumbed into pipe 20. Therefore, for example, some of the grey water devices, such as shower 14, may not be plumbed into pipe 20, but may simply discharge their waste as normal. The pipe 18 is connected to a mains water supply, which also supplies the grey water producing appliances 12, 14, and 15, in the usual way. Note that the mains water supply is not connected to the secondary appliances 24 and 26, and instead the only supply they receive is via the pipe 22 from the device 10. Thus, there is no need for the secondary appliances 24 and 26 to have two sets of plumbing, in order to be able to use both grey water and clean water.

The operation of the above described system is straightforward. When a grey water producing appliance 12, 14, or 15 is used, instead of the grey water being discharged into the sewer system in the conventional way, it is instead piped via pipe 20 to the central handover device 10. However, the central device 10 does not store the grey water therein, and instead simply causes the grey water to be retained within the primary appliance such as the bath, sink, or shower basin in which the grey water was produced, as well as within the pipework 20 and 22 leading to and from the central device, until such time as it is required. Thus, device 10 does not need capacity to store all of the grey water which has been produced, and hence can be of particularly compact construction. In particular, the device 10 need only be large enough to contain the components necessary to perform the seamless handover function to be described next, for this reason that no storage of the grey water is required.

Assume that one of the primary appliances 12, 14, or 15 has been used, and that a grey water supply is available. In this case a regulating mechanism in the device 10 acts to allow the grey water through the output port of the device 10 into the pipe 22 to supply the secondary appliances 24 and 26. When the secondary appliances 24 and 26 are operated, therefore, they will use the grey water supplied thereto from the primary appliances 12, 14, or 15, via the central device 10.

As the secondary appliances 24 and 26 operate, however, the grey water supply from the primary appliances 12, 14, or 15 will be slowly exhausted. In this case, the regulating mechanism within the central device 10 operates to detect that the grey water supply has become exhausted, and to then allow clean water from the main supply via the pipe 18 into device 10, for output via the pipe 22 to the secondary appliances 26 and 24. Thus, as far as the secondary appliances 26 and 24 are concerned, the supply of water by the pipe 22, whether it be clean water, or grey water, is continuous, and hence their operation is not interrupted and impaired. By providing such operation, the central device 10 is able to provide a seamless switchover between the grey water supply and the mains water supply as the grey water supply becomes exhausted, but thus allowing for the grey water supply to be completely recycled within the secondary appliances 24 and 26 without a user having to perform any action to switch over the input supplies of the secondary devices 24 and 26 to the grey water supply. Moreover, by retaining the grey water within the primary appliance in which it is generated, as well as within the pipework, no secondary storage tank which, by nature of the water it is storing, is prone to be unhygienic and to be regularly clogged, is required. Furthermore, with such a system the primary appliances producing the grey water can be plumbed directly into the central appliance 10, and hence no action is required of the user to, for example, switch the waste pipe of the appliances to plumbing which leads to the central appliance 10. Instead, by action of the central appliance 10, the grey water left in the sanitary appliances and pipework will be used as the secondary appliances 24 and 26 are operated.

With such a system, therefore, recycling of grey water for use in secondary appliances such as dishwashers, washing machines, or for irrigation purposes in a garden, becomes very straightforward.

The internal components and operation of the central device 10 will now be described with respect to Figures 2 and 3.

Figure 2 illustrates a vertical cross section through the central device 10. More particularly, the central device 10 comprises a cylindrical housing 2 having cylindrical side walls, and a sealed upper end, such that the housing 2 can be considered to be an inverted cylinder, with an open lower end. The open lower end has projecting therefrom a flange 2.1 which extends around the circumference of the open end outwardly projecting. The underside of the upper surface of the housing 2 has provided thereon a shouldered pin 2.2 extending into the interior volume of the housing 2 along the central axis thereof. The shouldered pin 2.2 is divided into two sections, with an upper section nearest to the under surface of the sealed end being of a circular shape around, and a lower section at the distal end of the pin from the sealed end of the housing being of square or other appropriate cross section, such that when a correspondingly shaped element is placed over the square part of the pin that element cannot rotate therearound.

The open end of the housing 2 provided with the flange 2.1 attaches to a manifold portion 1, which is circular in shape and provided with a lip portion 1.7, into which the flange portion 2.1 of the housing 2 may engage, such that the manifold 1 is secured over the open end of the housing 2. The lip 1.7 and the flange 2.1 are preferably correspondingly shaped so as to form a water tight seal between the manifold 1 and the housing 2. In order to allow the housing 2 to be removed from the manifold flange 1, the side walls of the housing 2 are preferably made from a resilient material, such that the housing 2 may be removed from the manifold flange 1 by applying pressure to the side walls at the open end of the housing, to remove the flange 2.1 from underneath the lip 1.7. It should then be possible to remove the housing 2 from the manifold 1. The manifold 1 is provided thereon with numerous ports having pipes attached. In particular, the manifold 1 is provided with a first outlet port 1.1, to which the pipework 22 may be attached to supply the secondary appliances 24 and 26. A first input inlet 1.5 is also provided, to which a pipe 1.6 is attached extending into the housing 2, and which delivers to the head of the chamber formed by the housing 2 when attached to the manifold 1. The inlet 1.5 in use is attached to pipework 20, to receive grey water from the primary appliances 12, 14, or 15.

Additionally provided in the manifold 1 is a second inlet 1.2, to which is attached pipe 1.3 extending into the chamber formed by the housing 2. The second inlet 1.2 is located in the centre of the manifold, such that the pipe 1.3 extending into the interior of the housing therefrom extends along the central axis of the housing 2. The pipe 1.3 is terminated with a valve head arrangement 3, for regulating the flow of fluid, being in the described embodiment, clean water, therefrom. In this respect, the second inlet 1.2 is attached to the pipework 18, which receives clean water from the mains water supply. The manifold 1 around the base of pipe 1.3 towards the manifold end is built up around the pipe for a short length, to provide a shoulder 1.4, to provide support for a part of the valve head arrangement 3, as described later.

With respect to the relative diameters of inlets 1.2, and 1.5, pipes 1.3, and 1.6 and the outlet 1.1, preferably the inlet 1.5 and the pipe 1.6 are of greater diameter than the inlet 1.2 and the pipe 1.3, and also of greater diameter than the outlet 1.1. This is preferable to try and ensure that the supply of grey water through the inlet 1.5 and pipe 1.6 is greater than the demand from secondary appliances output through the outlet 1.1, whilst grey water is still available. However, whether such measures are effective will of course depend upon the flow rate out of the outlet 1.1, as well as the pressure, and hence flow rate, at which water can be supplied through the inlet 1.5 and pipe 1.6. As will be described later, however, where the demand from the secondary appliances is greater than the rate at which water can be supplied to the inlet 1.5, the automatic regulating effect of the regulating mechanism incorporating the valve head arrangement 3 will act to ensure that the grey water supplied through the inlet 1.5 and pipe 1.6 is supplemented by clean water through the inlet 1.2, and pipe 1.3. The regulating mechanism comprises a float valve formed from valve head arrangement 3, and float 4. The valve head arrangement 3, being a cut off valve, comprises a valve seat 3.5 which is provided at the head of pipe 1.3, and provides a valve seat into which a valve head may be driven, to form a water tight seal which prevents water passing out of the inlet pipe 1.3. The valve head is provided on plunger 3.4, which is mounted via a square sinking on the square end of pin 2.2. Thus, the plunger 3.4 may slide up and down pin 2.2, but may not rotate therearound. The upper surface of plunger 3.4 being the surface closest to the end wall of housing 2.2 from which the pin 2.2 projects is angled at a relatively shallow angle, as will be described later. The plunger 3.4 slides up and down the square part of pin 2.2 such that the valve head part thereof may be seated in the valve seat 3.5 to form a water tight seal therewith, as described above.

Additionally provided is a rotating sleeve 3.1, which is coaxially arranged around pipe 1.3, and rests at its lower end thereof on the shoulder 1.4 formed in the manifold 1. The sleeve 3.1 extends from the shoulder 1.4 coaxially and substantially parallel with the pipe 1.3, up to the end wall of the housing 2.2, such that the sleeve is held between the end wall of the housing 2.2, and the shoulder 1.4. The sleeve 3.1 is provided with ports 3.2 therein, formed in the sleeve at the portion of the sleeve which is just above valve seat 3.5 such that water exiting from the pipe 1.3 through the valve seat 3.5 may exit into the chamber formed by the housing 2 in the manifold 1 through the ports 3.2, when the valve head on the plunger 3.5 is not located in the valve seat. A head portion 3.3 of the sleeve 3.1 abuts against the end wall of the housing 2, and forms an annulus about the circular portion of pin 2.2, next to the end wall of the housing. The lower surface of the annulus in the interior of the sleeve is angled, at a corresponding angle to the angle provided on the upper surface of the plunger 3.4. The plunger 3.4 is then located on the pin 2.2 within the sleeve 3.1, such that at a first angular position of the sleeve 3.1 about the central axis of the arrangement the upper surface of the plunger 3.4 abuts against the lower angled surface of the annulus 3.3 such that the plunger 3.4 may retreat up the pin 2.2 to its maximum extent, thus removing the valve head from the valve seat 2.5. In this first angular position of the sleeve 3.1, therefore, the valve head arrangement 3 is open, and liquid may flow through the pipe 1.3 out of the valve head 3.5, and into the interior of the housing 2.

Additionally provided on the sleeve 3.1 are projecting lugs 3.6, which locate into a helical groove 4.1, provided on a float 4, as described next.

More particularly, with reference to Figures 2 and 3, the regulating mechanism further comprises the float 4 made from a material which will float in liquid such as water, or which is otherwise formed from a hollow body, and which is provided with a central open portion 4.1 extending from the top to the bottom of the float, as well as a groove 4.2, to accommodate pipe 1.6. The central portion 4.1 of the float 4 is arranged substantially parallel and coaxial with the pipe 1.3 and the sleeve 3.1, and the groove 4.2 is arranged about the pipe 1.6. Thus, in operation the float 4 may move linearly up and down the chamber within the housing 2 along the axis of the pipe 1.3 and sleeve 3.1, and is also prevented from rotating via the groove 1.6 which accommodates the pipe 1.6. In this respect, the pipe 1.6 forms a spline which prevents the float 4 from rotating about the axis of the pipe 1.3, sleeve 3.1 and hollow opening 4.1. Formed on the inner surface of the hollow opening 4.1 is a helical groove 4.3 into which the lugs 3.6 formed on the sleeve 3.1 project. The helical groove is at a relatively steep angle, and in particular with respect to the respective angles of the under surface of the annulus 3.3, and the upper surface of the plunger 3.4. The relative angles of the helical groove 4.3 and the surfaces of the annulus 3.3 and plunger 3.4 are such that for the same angular rotation of the sleeve 3.1, a much greater linear movement of the float 4 will be obtained than of the plunger 3.4. In this way, a mechanical advantage can be obtained from the motion of the float 4 up and down the sleeve 3.1, which causes the plunger 3.4 to be moved with greater force than would otherwise be the case. The helical groove and the lugs on the sleeve 3.1 are respectively located such that when the float 4 is located substantially towards the bottom of the chamber formed by the housing 2, the angular surface on the under side of the annulus 3.3 and upper surface of the plunger 3.4 are in substantial alignment such that they cleanly abut against each other, allowing the plunger 3.4 to move as far as possible from the valve seat 3.5 along pin 2.2. Thus, when the float 4 is towards the bottom of the chamber formed by the housing 2, the valve head arrangement is opened. The respective angles of the helical groove 4.3, and of the mating surfaces of the annulus 3.3 and plunger 3.4 are such that when the float 4 is located at the top of the pipe 3.1, then rotation of the sleeve 3.1 caused by movement of the lugs 3.6 within the helical groove 4.3 will have caused the plunger 3.4 to have been forced downwards, such that the valve head sits securely in the valve seat 3.5, by the helical action of the respective mating surfaces of the annulus 3.3 and the plunger 3.4.

The operation of the device 10 can now be described. Consider first the situation where no grey water is available from any of the primary appliances 12, 14, or 15. In this case, when the device 10 is first plumbed in and the supplies switched back on the chamber of the device will be empty. In this case, the float 4 will be at the bottom of the chamber as shown in Figure 2, and the valve head arrangement open. Since there will be no grey water supply from primary appliances 12, 14, and 15 via pipework 20 into the inlet 1.5, mains water will enter into inlet 1.2, rise up pipe 1.3, and enter the chamber through ports 3.2 in the sleeve 3.1. Assuming no demand from secondary appliances 24 and 26, the pipework 22 and subsequently the chamber of the device 10 will rapidly fill with water, causing the float 4 to move upwards along the sleeve 3.1.

The linear motion of the float 4 along the sleeve 3.1 will cause the sleeve 3.1 to rotate, by virtue of the lugs 3.6 being located within the helical groove 4.3 of the float. The rotation of the sleeve 3.1 causes the angled lower surface of annulus 3.3 at the top of sleeve 3.1 to bear against angled upper surface of plunger 3.4. Because plunger 3.4 cannot rotate, however, the respective angles of the upper surface of plunger 3.4 and lower surface of annulas 3.3 will cause plunger 3.4 to be forced downwards by the surfaces acting against each other, until the valve head on plunger 3.4 is located in the valve seat 3.5, and the supply of water through pipe 1.3 into the chamber is cut off. The device will then stay in this state, until secondary appliances 24 and 26 are switched on, and start to draw water through the outlet 1.1. In this case the float will drop slightly, the valve head will open, and water will be admitted through pipe 1.3 into the chamber, to replace the water being drawn out of the outlet 1.1. An equilibrium position is quickly reached wherein the rate of water entering into the chamber through the at least partially open valve head equals the rate at which water is drawn out through the outlet 1.1. Once the demand ends, water enters the chamber until float 4 reaches a position whereby the valve head is completely closed.

Assume now that a grey water supply comes available, for example by a person having had a bath, or the like. In this case, with the device 10 initially full of clean water and the float 4 causing the valve head to be closed grey water enters into the chamber through the inlet 1.5 and pipe 1.6. In this respect, the pipe 1.6 delivers the grey water to the head of the chamber, above the height at which the float rests when the valve is closed. Thus, grey water can enter into the chamber, and will continue to enter the chamber until the chamber is full. At this point, the sealed nature of the chamber will cause no more water to enter thereinto, and the grey water will be retained within the primary appliance which generated it e.g. the bath. This equilibrium state will then be maintained until a demand for water is generated by turning on one of the secondary appliances 24 or 26.

In this case, once a secondary appliance is switched on, water begins to be drawn through the outlet 1.1. However, because grey water is still present in the primary appliances, which form a grey water supply, grey water drawn out through the inlet 1.1 can be replaced via pipework 20 into the inlet 1.5 and pipe 1.6. Thus, as water is drawn out of the chamber to the outlet 1.1, it is replaced by grey water from the grey water supply formed from the primary appliance. Thus grey water is cycled through the device 10 and to the secondary appliances 24 and 26, until either the secondary appliances 24 and 26 finish their operation, or until the grey water supply is exhausted.

In this latter case, once the grey water supply is exhausted then as water is drawn from the outlet 1.1 it will no longer be replenished in the chamber through the inlet 1.5 and pipe 1.6. In this case the water level in the chamber will rapidly start to drop and the float 4 will fall with the water level. As the float 4 falls, however, the sleeve 3.1 is rotated by virtue of the lugs 3.6 located in the helical groove, and the plunger 3.4 is no longer forced into the valve seat 3.5. In such a case, mains water can then exit through the valve via ports 3.2 into the chamber, and then be supplied from the chamber through the outlet 1.1. Thus, as the grey water supply is exhausted, the valve head arrangement 3 is caused to open by virtue of the float 4 lowering in the chamber, such that water demanded from the outlet 1.1 is then supplied by the mains water. In this way, a seamless handover of water supply from the grey water supply to the mains water supply is performed, without the supply from the outlet 1.1 to the secondary appliances 24 or 26 being interrupted.

Consider now the case where a grey water supply is present, but it is not able to supply water at the rate demanded by the secondary appliances 24 or 26. Jh this case, as water is drawn out of the outlet 1.1 faster than it can be replaced by the grey water supply through the inlet 1.5, the water level within the chamber will drop, and the float 4 will cause the valve arrangement to open, such that water can also be supplied via the mains from inlet 1.2. Thus, in this situation both a mix of grey water and clean water can be used to supply the secondary appliances, and in particular in the case where the flow rate of the grey water supply is not sufficient for the appliance. It should be noted, however, that in such a case priority is still given to the grey water supply, for the reason that as soon as the flow rate out of the device drops, the float 4 will move back up thus cutting off the mains water supply, but leaving the grey water supply open. Thus, the grey water supply is used as quickly as it is possible to deliver grey water to the device. With the above arrangement, therefore, an apparatus is provided which allows for the seamless handover from a first fluid supply to a second fluid supply, without the output being interrupted. Thus, all of the benefits described previously from being able to make use of the recycling of grey water can be obtained. Moreover, the mechanism which allows the seamless handover to be performed described above and shown in Figures 2 and 3 can be produced in an extremely compact form, such that the actual size of the device 10 is reduced. The compactness of the device is further reinforced by the fact that it does not need to store grey water therein, and instead the grey water is stored within the primary appliances themselves and the connecting pipework, or in some optional intermediate storage tank. By removing the necessity for the central device 10 to have to store the grey water, its dimensions can be much reduced, and in fact it need only be big enough to provide standard sized plumbing ports for the inlets and outlets, and to allow for an adequate ratio between the respective range of movement of the float 4, and the plunger 3.4, to achieve a suitable mechanical advantage from the respective helical surfaces. As such, the device may be made extremely compact. In this respect, we would envisage internal volumes in the range of 1 to 6 litres to be readily achievable, although other smaller or larger volumes may also be possible.

It should also be noted that various modifications may be made to the above described mechanism to provide further embodiments of the invention. For example, in another embodiment instead of the helical groove 4.3 being provided in the float 4 and the projecting lugs 3.6 on the sleeve 3.1, these elements of the mechanism may be reversed, and instead the sleeve 3.1 may have formed therein the helical groove in its outer surface, with the float 4 having projecting lugs projecting into the helical groove in the sleeve. Movement of the float 4 would then cause the projecting lugs to slide within the groove provided on the outer surface of the sleeve 3.1, thus causing the sleeve to rotate. In this respect, the mechanism will be equivalent as described previously.

Equivalently, in other embodiments instead of a helical groove being formed on either the float 4 or the sleeve 3.1, a helical spline may be provided on one of the parts, with the other of the parts being provided with one or more spline engaging parts, such as a U-shaped clip, or the like, to engage over the spline. Such an arrangement is effectively the reverse of the previously described embodiments wherein projecting lugs fit into the groove, and instead, in this alternative embodiment the projecting helical spline fits into one or more spline receiving parts such as the U-shaped clips provided on the other part. As described above, the spline may be provided on either the float 4 or the outer surface of the sleeve 3.1, with the corresponding spline engaging parts being provided on either the outer surface of the sleeve 3.1, or the float 4, as appropriate. In use the spline engaging parts would slide up and down the spline as the float 4 moves within the vessel, thus causing rotation of the sleeve. It should also be noted that alternative valve head arrangements may also be used other than the one described previously. For example, instead of the plunger 3.4 and valve seat 3.5 being provided, the pipe 1.3 may extend further up the vessel, but be sealed at its upper end. To allow water out of the pipe 1.3, output ports are cut in the side wall of the pipe 1.3 at the same level as the output ports 3.2 in the sleeve 3.1. The sleeve 3.1 is then arranged such that the output ports thereof are in alignment with the output ports of the pipe 1.3 when the float is at the bottom of the vessel, but then are not in alignment such that the sleeve blocks the output ports in pipe 1.3 when the float 4 is at the top of the vessel. That is, the rotation of the sleeve 3.1 rotates the output port 3.2 in the sleeve out of alignment with the output ports in the pipe 1.3, thus blocking the output ports in the pipe 1.3. Preferably, a water tight seal or gasket is provided around the output ports in the pipe 1.3 over which the sleeve 3.1 may slide, such that when the sleeve 3.1 blocks the output ports in the pipe 1.3, water does not leak out between the outer surface of the pipe 1.3, and the inner surface of the sleeve 3.1. Moreover, such an alternative valve head arrangement would mean that the squared portion of pin 2.2 was not required, although the round upper portion of pin 2.2 is retained, around which the sleeve 3.1 would rotate. Such an alternative valve head arrangement incorporated within the device 10 would allow the device 10 to operate as in the previously described embodiment, although such an arrangement does not obtain the mechanical advantage in the valve closing mechanism which the mating surfaces of plunger 3.4 and annulus 3.3 provide in the first embodiment.

Other known valve head arrangements which may also be suitable may also be known in the art.

Further modifications may also be made to provide additional embodiments. For example, a filter to filter the water output from the device may be provided, either internal to the device above the outlet 1.1, or placed within the line of pipe 22, after outlet 1.1. Such a filter is preferably in the described embodiments arranged to filter the grey water output through outlet 1.1, for example to remove bits of solid waste which may have drained from the primary appliances with the grey water, and which might foil the operation of the secondary appliances 24 or 26. Alternatively, in other embodiments, the filter may be provided on or about the inlet

1.5 from the grey water supply, and thus filters the grey water as it is input to the vessel.

As described previously, the vessel housing 2 is adapted to be removable from the manifold 1 via the operation of flange 2.1 and lip 1.7 on the manifold. However, in order to be able to remove the vessel housing 2 from the manifold 1, for example for cleaning, it is necessary to isolate the device 10 from the mains water supply at the very least. It will often not be necessary to provide isolation from the grey water pipe 20, as cleaning can be scheduled at a time when no grey water is to be produced. However, in order not to affect the operation of secondary appliances 24 and 26, it is also preferable that the water supply to such appliances be maintained even while the central device 10 has been removed from the water circuit.

To this end, in another embodiment of the invention a switching valve is placed at the end of pipework 18 and 22, at inlet 1.2, and outlet 1.1. The valve in one position operates to allow clean water into inlet 1.2 from pipework 18, and to receive water from outlet 1.1 into pipework 22, as described previously, and in another position to bypass inlet 1.2 and outlet 1.1, and feed clean water from pipework 18 direct to pipework 22. hi this way the device 10 can be switched out of the water circuit by the valve, and can then be opened, for example for cleaning or maintenance.

An example of such a switching valve which may be used is shown in Figures 4 and 5. It should be noted that other valve designs which perform the above function may also be incorporated within other embodiments.

Returning to the valve at Figures 4 and 5, however, the valve comprises a valve body 42 which is of substantially circular cross section, and which is provided with four ports 42, 44, 46, and 48, which may be used as inlet or outlet ports as appropriate, leading from the exterior of the valve into the valve body. The valve body has a central axis which forms the centre of the circular cross section of the valve body, extending in a direction orthogonal to the circular cross section. Rotatably mounted on this axis is a divider plate 40 which extends from one side of the valve body to the other, to effectively divide the interior volume of the valve body into a first sub volume 44 and a second sub volume 46. The end walls of the divider plate preferably contact the inner walls of the valve body with such a close fit as to provide a substantially water tight seal therebetween, although the inner walls of the valve body or end walls of the divider plate may be coated in a gasket material to aid such a seal. The divider plate 40 is rotatable about the central axis of the valve body such that the sub volumes 44 and 46 move about the interior volume of the valve body, as shown in Figure 5. The whole shape of the valve body 42 is dependent upon the shape of the divider plate

40, and is defined by a rotation of the divider plate 40 about the central axis of the valve body. Thus, where the divider plate 40 is substantially rectangular in shape when viewed in a direction orthogonal to the axis then the valve body 42 would be substantially cylindrical, in view of a rotation of a rectangle about a central axis thereof defining a cylinder. If, however, the divider plate 40 was circular in shape when viewed from a direction orthogonal to the axis of the valve body, then the valve body 42 would be spherical. Other shapes of the divider plate 40 are of course possible, which would give corresponding shapes for the valve 42, defined by the rotation of the divider plate 40 about the central axis. The operation of such a valve is straightforward. When the divider plate is in a first position as shown in Figure 4 the first sub volume 44 connects ports 422 and 424, such that fluid may flow from one port to the other in either direction. Likewise, the sub volume 46 connects ports 426 and 428, such that fluid may flow from one to the other, as shown.

To achieve a switching operation, the divider plate 40 is then rotated 90 degrees, which causes the sub volumes 44 and 46 to move within the interior volume of the valve body 42. To achieve rotation of the divider plate 40 the central axis of the divider plate may extend outside the valve body 42, and be fitted with a knob, handle, or the like, for operation by a user. When the divider plate 40 has been rotated 90 degrees, the first sub volume 44 then connects ports 424 and 428, whereas the second sub volume 46 connects ports 422 and 426, such that fluid may flow between these respective pairs of ports, as shown. Thus, with such a valve design any particular port may be connected to another of the ports immediately adjacent to it around the valve body, but cannot be connected to the port opposite on the valve body.

When used in a grey water recycling system of the presently described embodiments, the valve 42 is connected such that port 428 is connected to pipework 22, and port 426 is connected to pipework 18. Similarly, port 422 is connected to inlet 1.2, and port 424 is connected to outlet 1.1. With such connections, when the divider plate 40 is in the position shown in Figure 4 the device 10 is switched out of the water circuit, such that clean water from pipework 18 flows directly into pipework 22, without going through the device 10. In contrast, to switch the device 10 into the circuit the divider plate 40 is switched to the position shown in Figure 5, in which case clean water from pipework 18 is then switched into inlet 1.2 of device 10, and water from outlet 1.2 of device 10 is received into port 424, and switched to pipework 22 via port 428. Such a valve therefore conveniently allows the device 10 to be switched in and out of the water circuit. In the above described embodiments grey water is retained within the primary appliances and the connecting pipework, which together form a first exhaustible supply, by virtue of the vessel housing 2 being enclosed. Thus, when a grey water supply is present the grey water can fill up the pipework 22 and the interior volume of the vessel housing 2, and then back up the pipework 20 to the primary appliance. Thus, where for example the primary appliance is a bath, when the user pulls the plug on the bath to let out the water, the water level in the bath will drop slightly whilst the vessel housing 2 fills up and the pipework 20 backs up, but will not drop any further until the secondary appliances start to use the grey water. If the vessel housing 2 were not enclosed and instead were open this effect would not be achieved, and the grey water would overflow the open housing and be lost. Thus, the enclosed nature of the vessel housing 2 retains the grey water within the grey water supply.

This function may be achieved by alternative means however. For example, in another embodiment the housing 2 may be open at the top, such that water would overflow therefrom, hi this case, to retain the grey water within the supply a regulating mechanism such as a valve or the like is attached to the head of pipe 1.6, to prevent grey water from exiting the pipe 1.6 into the housing 2 when it would then cause the liquid in the housing 2 to overflow. The valve may be a float valve of the type described previously, the housing 2 being adapted accordingly to accommodate the two float valves, hi such a case, however, the float valve attached to pipe 1.6 should be arranged to close off the grey water supply into the vessel when the liquid levels in the vessel are at a higher level than are required to close off the clean water supply into the vessel. Such arrangement can be achieved by having a different helical pitch used in the float valve, such that the float must travel further to close the valve. Use of such a second regulating mechanism on the grey water inlet ensures that grey water is retained in the grey water supply when not required. Further modifications will be apparent to the skilled person to provide additional embodiments, which are intended to be encompassed by the appended claims.

Claims

1. A float valve for use in a liquid containing vessel, comprising a float and a rotary part, one of said float or said rotary part having a helical element and the other of said float or said rotary part having a helical element engaging part arranged in use to engage with the helical element whereby to cause a rotary motion as said float moves with the liquid levels in the vessel, the valve further comprising a valve head arrangement operable in response to said rotary motion.

2. A float valve according to claim 1, said valve head arrangement further comprising a valve head and a valve seat, the rotary part being subject to said rotary motion and being further arranged to act on said valve head to move the head into the valve seat.

3. A float valve according to claim 2, wherein said rotary part and said valve head have corresponding helical mating surfaces, whereby the rotary motion of said rotary part is translated into a linear motion of said valve head into the valve seat.

4. A float valve according to claim 3, wherein the respective pitches of said helical mating surfaces of said rotary part and said valve head and said helical groove are arranged so as to obtain a mechanical force advantage from the movement of said float.

5. A float valve according to any of claims 1 to 4, wherein said float is provided with said helical groove as said helical element and said rotary part comprises a sleeve having at least one lug arranged to fit into the helical groove on said float, said float being arranged substantially concentric with said sleeve whereby motion of said float in said vessel causes rotary motion of said sleeve.

6. A float valve according to claim 5, wherein an input port to said valve comprises an input pipe through which said liquid flows, said input pipe being arranged within said sleeve axially parallel thereto, said input pipe being terminated with said valve head arrangement.

7. An apparatus for providing a seamless supply of fluid from a first exhaustible fluid supply and a second fluid supply, said apparatus comprising: a switching vessel having at least one first inlet for receiving fluid from the first exhaustible fluid supply and at least one second inlet for receiving fluid from the second fluid supply and at least one fluid outlet; and a regulating mechanism arranged to provide fluid from said first exhaustible supply for output at said at least one fluid outlet whilst said first exhaustible supply is not exhausted, and fluid from said second fluid supply when said first exhaustible fluid supply becomes exhausted; the apparatus being further provided with means arranged such that fluid is retained substantially within said first exhaustible fluid supply and said second fluid supply when fluid is not required from said at least one outlet.

8. An apparatus according to claim 7, wherein said means comprise said switching vessel being a sealed vessel.

9. An apparatus according to claim 7, wherein said means comprise a second regulating mechanism arranged to regulate said at least one first inlet to allow fluid into said vessel from said first exhaustible fluid supply as fluid is drawn from said at least one fluid outlet.

10. An apparatus according to any of claims 7 to 9, wherein said regulating mechanism comprises an inlet regulator arranged to regulate said at least one second inlet to allow fluid into said switching vessel from said second fluid supply when said first exhaustible fluid supply becomes exhausted, whereby said fluid within said vessel is available for output at said at least one fluid output.

11. An apparatus according to any of claims 7 to 10, wherein said fluid is a liquid, and said regulating mechanism comprises a float valve, said vessel being adapted to buffer an amount of said liquid, and said float valve operating to permit fluid entry through said at least one second inlet when the level of liquid in said vessel falls below said amount.

12. An apparatus according to claim 11, wherein said float valve comprises a float and a rotary part, one of said float or said rotary part having a helical element and the other of said float or said rotary part having a helical element engaging part arranged in use to engage with said helical element whereby to cause a rotary motion as said float moves with the liquid levels in the vessel, said regulating mechanism being further arranged so as to be operable in response to said rotary motion.

13. An apparatus according to claim 12, said float valve further comprising a valve head and a valve seat, the rotary part being subject to said rotary motion to act on said valve head to move the head into the valve seat.

14. An apparatus according to claim 13, wherein said rotary part and said valve head have corresponding helical mating surfaces, whereby the rotary motion of said rotary part is translated into a linear motion of said valve head into the valve seat.

15. An apparatus according to claim 14, wherein the respective pitches of said helical mating surfaces of said rotary part and said valve head and said helical groove are arranged so as to obtain a mechanical force advantage from the movement of said float.

16. An apparatus according to any of claims 12 to 15, wherein said float is provided with a helical groove as said helical element and said rotary part comprises a sleeve having at least one lug arranged to fit into the helical groove on said float, said float being arranged substantially concentric with said sleeve whereby motion of said float in said vessel causes rotary motion of said sleeve.

17. An apparatus according to claim 16, wherein said second inlet comprises a first pipe, said sleeve being arranged substantially concentric with said pipe.

18. An apparatus according to any of claims 12 to 17, comprising means arranged to prevent said float from rotating.

19. An apparatus according to claim 18, wherein said means comprises a second pipe extending from said first inlet, said float being shaped to accommodate said pipe and slide along said pipe.

20. An apparatus according to any of claims 7 to 19, wherein said vessel comprises a manifold portion having said inlets and said at least one outlet therein, and a sidewall portion, said sidewall portion being removable from said manifold portion.

21. An apparatus according to any of claims 7 to 20, and further comprising a filter for filtering fluid, arranged at or into the first inlet, and /or at or from the outlet.

22. An apparatus according to any of claims 7 to 21, and further comprising a switching valve having at least a first input port connected to said second fluid supply, and a second input port connected to said at least one fluid outlet, and at least a first output port, the valve being arranged to be switchable from a first state wherein fluid is able to pass from said second input port to said first output port, and a second state wherein fluid from said first input port is able to pass to said first output port.

23. An apparatus according to claim 22, wherein said switching valve further comprises a second output port connected to said at least one second fluid inlet, wherein in said first state fluid is able to pass from said first input port to said second output port.

24. An apparatus according to any of claims 7 to 23, wherein the fluid is liquid.

25. An apparatus according to claim 24, wherein the fluid is water, the first exhaustible fluid supply being at least one supply of "grey" water, and the second fluid supply being a mains water supply.

26. A system comprising: one or more first appliances which in use produce waste "grey" water; an apparatus according to any of claims 7 to 25; a mains water supply; and one or more second appliances which in use may use "grey" water; outlets of the first appliances being connected to the at least one first inlet, the mains water supply being connected to the at least one second inlet, and inlets of the second appliances being connected to the at least one outlet.

27. A system according to claim 26, wherein said first appliances comprise one or more selected from the group comprising: baths, sinks, showers, basins, and cisterns

28. A system according to claim 26 or 27, wherein said second appliances comprise one or more selected from the group comprising: washing machines, dishwashers, gardening tools.

29. A building comprising a system according to claims 26 to 28.

30. A switching valve comprising a valve body of substantially circular internal cross- section and a divider plate rotatably mounted co-axially with the valve body and extending from one side of an interior volume of the valve body to the other whereby to divide said interior volume into at least two sub-volumes, the valve body having at least first, second, and third ports disposed around the valve body, the disposal of said ports being such that when said divider plate is in a first position the first port and the second port open into the same sub-volume, and in a second position of said divider plate the second port and the third port open into the same sub-volume.

31. A valve according to claim 30, the valve body further having a fourth port disposed therein at a position such that when said divider plate is in a first position the first port and the second port open into the same one of the sub-volumes and the third port and fourth port open into another one of the sub-volumes, and in a second position of said divider plate the second port and the third port open into the same one of the sub-volumes and the first port and fourth port open into another one of the sub-volumes.

32. A valve according to claims 31 or 32 wherein the ports are equiangularly disposed around the valve body.