AU2003255208A1 - Tap and auxiliary valve assembly - Google Patents

Description

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION STANDARD PATENT Applicant(s): ROSS SHILTON Invention Title: TAP AND AUXILIARY VALVE ASSEMBLY The following statement is a full description of this invention, including the best method of performing it known to me/us: 2 TAP AND AUXILIARY VALVE ASSEMBLY Field of the Invention This invention relates to a tap and auxiliary valve assembly.

Background Art Taps (sometimes called faucets in some countries) are well known and generally include a water inlet which is connected to a water supply pipe, and a water outlet. A valve seat is disposed between the inlet and the outlet and the tap is opened and closed by a spindle which carries a valve element which selectively seats on the valve seat to prevent flow of water from the inlet to the outlet, or is moveable away from the seat to allow water to flow from the inlet to the outlet. Such taps are commonly used in domestic environments, both indoors and outdoors.

The valve which seats on the valve seat generally includes a rubber washer, and occasionally it is necessary to replace the rubber washer because the rubber washer does tend to wear and therefore can leak. In order to replace the rubber washer, the tap spindle is removed from the tap and the spindle, together with the valve, is therefore accessible so that the washer can be replaced and the spindle reattached to the tap.

In order to shut off water to the valve when the washer is replaced, it is usually necessary to shut off a primary water meter supply valve to the premises. This can be inconvenient if other taps are in use or required to be used during the time a washer is replaced on another of the taps. This is particularly disadvantageous if a single supply valve is associated with a number of different premises, such as in apartment blocks or the like.

3 In order to eliminate the need to shut off the supply valve to prevent water from flowing through the tap which is to be repaired, taps have been designed which include auxiliary valves which, when the main valve is removed for repair, shuts off water so water cannot flow through the tap. Conventional taps of this type are usually somewhat complicated, requiring a number of parts in order to locate the auxiliary valve within the tap and ensure proper operation of the auxiliary valve when a tap is disassembled for repair. One of the parts which is generally used is a spider which is located in the water flow path through the tap so as to support the auxiliary valve and, in particular, movement of the auxiliary valve.

The need to locate a spider which supports the auxiliary valve reduces the effective cross-sectional area of the water flow path at the spider, thereby reducing the flow of water through the tap.

Furthermore, in some environments it is necessary for taps or water flow valves to include a check valve function so that if the pressure of the water drops on the mains side of the tap or valve, water is not drawn back through the tap or valve into the mains supply. Generally, the check valve function is provided in a supply pipe to a building or dwelling. Furthermore, it is often required that in order to provide failsafe operation, two check valves be incorporated so that if one should fail or become worn, the other will still provide the check valve function. In many situations, this is achieved by providing the check valve assembly in a housing connected to a water supply pipe to a building so that the housing contains two check valves which operate independent of one another. A tap is also provided in close proximity so that water supply can be shut off manually if desired.

4 Summary of the Invention The object of this invention is to provide a tap and assemblies, which more reliably and more easily enable the shut off of water through a tap when it is desired to repair a main valve of the tap, and which does not adversely affect the flow of water through the tap when the tap is in normal operation.

The invention, in a first aspect, may be said to reside in a tap comprising: a main valve body having a water inlet and a water outlet and defining a flow passage through the body between the inlet and the outlet; a main valve seat located between the inlet and the outlet; a main valve having a washer for engaging the seat and moveable from a first position allowing water to flow from the inlet to the outlet, to a second position shutting off flow of water from the inlet to the outlet; a control assembly attached to the main valve for moving the main valve between the first and second positions; a first coupling and support portion on the control assembly; an auxiliary valve and an auxiliary valve seat within the tap, the auxiliary valve having a second cooperating coupling and support portion for engaging the first coupling and support portion so the auxiliary valve is supported within the main body by the control assembly without any additional support which would reduce the size of the flow passage; and wherein when the control assembly is attached to the tap, the coupling and support portions couple and engage with one another so as to push the auxiliary valve away from the second valve seat, and provide support to the auxiliary valve, so that when the control assembly is actuated to move the valve to the second position water is 5 able to flow passed the auxiliary valve and second valve seat to the outlet, and when the control assembly is detached from the tap to allow replacement of the washer, the control assembly and valve separate from the valve body as a single unit, the first coupling and support portion is separated from the second coupling and support portion, and the auxiliary valve is able to move to seat against the second valve seat to shut off flow of water to the outlet.

Because the auxiliary valve is supported by the engagement of the coupling and support portions, the auxiliary valve is properly supported without any additional internal structure within the valve, in a correct orientation so that it will move into proper sealing engagement with the second valve seat upon detachment of the control assembly from the tap. This ensures that the valve is properly shut off and water is not able to flow to the outlet, nor to the opening in which the control assembly is attached.

Thus, it is not necessary to shut off a supply valve to the tap and other taps also associated with the supply valve can therefore be used during repair of the tap.

Furtherstill, because the main valve is fixed to the control assembly and comes away from the valve body with the control assembly as a single unit, less parts are needed and therefore assembly, disassembly and reassembly of the tap is much easier. Furtherstill, because the support of the auxiliary valve is by way of the first coupling and support portion and second coupling and support portion without any additional support which would reduce the size of the flow passage, the flow passage is not adversely effected, and therefore the flow of water through the valve is not reduced. In other words, the need for a supporting spider within the flow passage to hold and support movement of the auxiliary valve is not required, hence the spider does not partially block the 6 flow passage which would reduce the effective size of the flow passage and therefore reduce the flow of water through the passage during normal operation of the valve.

Thus, a better flow of water is achieved by the tap of the present invention.

Preferably the control assembly includes a valve bonnet releasably couplable to the main body, the valve bonnet supporting a spindle for rotation relative to the bonnet, the spindle carrying the main valve and washer so that upon rotation of the spindle, the spindle and main valve and washer move away from the valve seat to allow water to flow from the inlet to the outlet, and upon rotation of the spindle in the opposite direction, the valve and washer are moved toward the main valve seat to engage the main valve seat to shut off flow of water from the inlet to the outlet.

Preferably the engagement of the first and second coupling and support means supports the auxiliary valve for movement between an extreme position away from the second valve seat when the main valve is seated on the main valve seat, and a position adjacent to the secondary valve seat, but spaced from the secondary valve seat, when the main valve is in the second position away from the main valve seat.

Preferably the biasing means comprises a spring.

Preferably the auxiliary valve has a circumferential shoulder for engaging the spring.

Preferably the main body has an abutment for supporting the other end of the spring.

Preferably the first coupling and support portion comprises a stem on the spindle and the second coupling 7 and support portion comprises a sleeve in the auxiliary valve, so that the stem locates in the sleeve to support and guide movement of the auxiliary valve between the extreme and adjacent positions without additional structural support within the main valve body.

In other embodiments the stem could be arranged on the auxiliary valve and the sleeve arranged on the valve stem.

Preferably the auxiliary valve has a generally disc shaped body including the shoulder and an upwardly extending post section which includes the sleeve.

In one embodiment of the invention the main valve is fixed to the control assembly but moveable relative to the control assembly and a spring is provided between the control assembly and the main valve for biasing the main valve towards the valve seat so that in the event of loss of water pressure on a mains side of the tap, the spring biases the main valve relative to the control assembly into engagement with the main valve seat to provide a check valve function and prevent flow of water from the outlet of the tap back to the inlet, and therefore to the mains side of the tap.

In one embodiment the auxiliary valve is also supported by the biasing means.

The invention may also be said to reside in a main valve assembly for a tap which includes an auxiliary valve seatable on a second valve seat to shut off flow of water through the tap when the main valve assembly is removed from the tap for repair, the assembly comprising: a bonnet for releasable connection to the tap; a spindle arranged in the bonnet for rotation relative to the bonnet; a main valve including a valve washer attached to 8 the spindle for movement with the spindle to move the valve upon actuation of the spindle from a first position which allows water to flow through the tap to a second position which will prevent flow of water through the tap; a first coupling and support portion on the valve assembly for engaging and supporting the auxiliary valve when the main valve assembly is attached to the tap so the first coupling and support portion guides and supports movement of the auxiliary valve between an extreme position away from the second valve seat and an adjacent but spaced position away from the second valve seat when the spindle is moved to open and close the tap, and when the main valve assembly is detached from the tap to allow repair or replacement of the valve assembly, the first coupling and support portion disengages from the auxiliary valve so the auxiliary valve can move into a position against the second valve seat to shut off flow of water through the tap; and wherein the engagement of the coupling and support portion with the auxiliary valve provides support for the auxiliary valve so that a flow path through the tap from an inlet of the tap to an outlet of the tap is not reduced by the need for other supporting elements to support the auxiliary valve.

Preferably the first coupling and support portion comprises a stem on the spindle for engaging with a second coupling and support portion comprised of a sleeve on the auxiliary valve so that the stem locates in the sleeve to support and guide movement of the auxiliary valve between the extreme and adjacent positions without additional structural support within the valve body.

In other embodiments the stem could be arranged on the auxiliary valve and the sleeve arranged on the valve stem.

The invention may also be said to reside in an auxiliary 9 valve for a tap which has a main valve assembly moveable relative to a main valve seat to selectively allow water to flow from an inlet of the tap to an outlet of the tap, the tap having a second valve seat, the auxiliary valve comprising: a valve body for engaging the second valve seat to shut off water through the tap when the main valve assembly is removed from the tap to allow repair or replacement of the main valve assembly; a second coupling and support means on the auxiliary valve for engaging the main valve so the auxiliary valve is supported by the main valve when the main valve is moved from a first position allowing water to flow through the tap, to a second position shutting off flow of water through the tap, whereupon during which movement the auxiliary valve is supported for movement between an extreme position away from the second valve seat to a position adjacent to but spaced from the second valve seat, and whereupon when the main valve assembly is removed from the tap, the second coupling and support means disengages from the main valve to allow the auxiliary valve to move into contact with the second valve seat to shut off flow of water through the tap; and wherein the engagement between the second coupling and support means and the main valve provides the only support for the auxiliary valve so that additional supporting elements are not required in a flow path in the tap between an inlet of the tap and an outlet of the tap so the size of the flow path is not reduced by any other support element.

Preferably the auxiliary valve has a circumferential shoulder for engaging a spring when the auxiliary valve is assembled in the tap.

Preferably the second engaging and coupling means comprises a sleeve in the auxiliary valve and the main 10 valve has a first coupling and support portion comprised of a stem so that the stem locates in the sleeve to support and guide movement of the auxiliary valve when assembled in the tap between the extreme and adjacent positions without additional structural support within the valve body.

In other embodiments the stem could be arranged on the auxiliary valve and the sleeve arranged on the valve stem.

Preferably the auxiliary valve has a generally disc shaped body including a shoulder and an upwardly extending post section which includes the sleeve.

An object of a second invention is to provide a tap which is less likely to jam if the tap is over-tightened during closing of the tap.

The invention also provides a main valve assembly for a tap which includes a main valve seat, comprising: a spindle mounted for rotation in the assembly to selectively open and close the tap; a main valve supported on the spindle for movement with the spindle so as to move the valve between an open position and a shut off position; the main valve including a valve support having at least one abutment portion; and a resilient, substantially flat washer supported by the valve support and projecting beyond the abutment so that when the spindle is operated to close the valve by moving the washer to seat against the valve seat, the abutment prevents over-tightening and jamming of the main valve assembly by abutting on the valve seat to thereby limit the amount of compression of the resilient washer and movement of the spindle toward the valve seat.

Thus, because the abutment prevents over-tightening of the 11 tap and therefore limits the amount of compression, the tap is not likely to jam because of over-tightening when closing the tap.

Preferably the support comprises a housing and the abutment portion comprises a generally annular wall which defines a space into which the washer locates.

An object of a third invention us to provide a tap which provides for shut off of water through the tap when it is desired to repair a main valve of the tap, and which also includes a check valve function.

This invention provides a tap comprising: a main valve body having a water inlet and a water outlet; a main valve seat located between the inlet and the outlet; a main valve having a washer for engaging the seat and moveable from a first position allowing water to flow from the inlet to the outlet, to a second position shutting off flow of water from the inlet to the outlet; a control assembly coupled to the main valve for moving the main valve between the first and second positions, the main valve being moveable relative to the control assembly; a spring disposed between the control assembly and the main valve assembly for biasing the main valve assembly towards the valve seat; a first engaging portion; an auxiliary valve and an auxiliary valve seat within the tap, the auxiliary valve having a second engaging portion for engaging the first engaging portion; and wherein when the control assembly is attached to the tap, the engaging portions engage with one another so as to push the auxiliary valve away from the second valve 12 so that when the control assembly is actuated to move the valve to the second position, water is able to flow passed the auxiliary valve and second valve seat to the outlet, and when the control assembly is detached from the tap to allow replacement of the washer, the auxiliary valve is moved to seat against the second valve seat to shut off flow of water to the outlet; and wherein when the main valve is away from the main valve seat and water pressure at the inlet of the valve reduces, the spring biases the main valve relative to the control assembly so the main valve is biased into engagement with the main valve seat to provide a check valve function to prevent backflow of water from the outlet side of the tap to the inlet.

Thus, the tap provides for shut off of water in circumstances where it is necessary to remove the main valve for repair or replacement, and also provides a check valve function so that if the pressure of water drops on the mains side of the tap, the main valve is closed so that water cannot flow back from the outlet side of the tap to the inlet and mains side of the tap.

Preferably the control assembly includes a valve bonnet releasably couplable to the main body, the valve bonnet supporting a spindle for rotation relative to the bonnet, the spindle carrying the main valve and washer so that upon rotation of the spindle, the spindle and main valve and washer move away from the valve seat to allow water to flow from the inlet to the outlet, and upon rotation of the spindle in the opposite direction, the valve and washer are moved toward the main valve seat to engage the main valve seat to shut off flow of water from the inlet to the outlet.

Preferably the engagement of the first and second engaging portions supports the auxiliary valve for movement between 13 an extreme position away from the second valve seat when the main valve is seated on the main valve seat, and a position adjacent to the secondary valve seat, but spaced from the secondary valve seat, when the main valve is in the second position away from the main valve seat.

Preferably the biasing means comprises a spring.

Preferably the auxiliary valve has a circumferential shoulder for engaging the spring.

Preferably the main body has an abutment for supporting the other end of the spring.

Preferably the first coupling and support portion comprises a stem on the spindle and the second coupling and support portion comprises a sleeve in the auxiliary valve, so that the stem locates in the sleeve to support and guide movement of the auxiliary valve between the extreme and adjacent positions without additional structural support within the main valve body.

In other embodiments the stem could be arranged on the auxiliary valve and the sleeve arranged on the valve stem.

Preferably the auxiliary valve has a generally disc shaped body including the shoulder and an upwardly extending post section which includes the sleeve.

An object of a fourth invention is to simplify the need for failsafe check valve operation in a water supply system to a building dwelling or the like.

This invention provides a water supply system comprising: a water supply pipe; a housing in the water supply pipe and having a first check valve for preventing backflow of water from an 14 outlet side of the water supply system to a mains side of the water supply system in the event of a reduction in pressure at the mains side; a tap in the water supply side spaced from the housing, the tap having: a main valve; a main valve seat; a control assembly for moving the main valve between a first position away from the main valve seat and a second position in engagement with the main valve seat to selectively allow flow of water through the supply pipe and tap, or shut off flow of water through the tap; a check valve within the tap for closing flow of water through the tap in the event of reduction of water pressure on the mains side to thereby provide a second check valve for preventing backflow of water from the outlet side to the mains side.

Thus, according to this aspect of the invention, because the second check valve is provided in the tap, the housing can be made smaller and therefore the water supply system to the building can be much more compact, and therefore easier to install, particularly if space is a consideration, and also can possibly be made less expensively.

Preferably the check valve comprises the main valve, the main valve being arranged for movement relative to the control assembly, a spring disposed between the control assembly and the main valve for biasing the main valve towards the main valve seat so that when normal pressure exists and the tap is open, water pressure pushes the valve seat against the bias of the spring to thereby maintain the main valve away from the valve seat to allow flow of water through the tap, but if there is a reduction 15 in pressure at the mains side, the spring biases the main valve relative to the control assembly so the main valve is moved into engagement with the main valve seat to prevent backflow of water from the outlet side of the tap to the mains side.

Brief Description of the Drawings A preferred embodiment of the invention will be described, by way of example, with reference to the accompanying drawings in which: Figure 1 is a view of a tap or faucet showing the preferred embodiment of the invention in a disassembled condition allowing repair or replacement of a washer of a main valve assembly of the tap; Figure 2 is a view of the tap of Figure 1 in an assembled condition with the main valve assembly partially separated from tap; Figure 3 is a view of the tap in a fully assembled position with the tap fully open to allow water to flow from an inlet of the tap to an outlet of the tap; Figure 4 is a view in a fully assembled condition with the tap in a fully closed position shutting off flow of water from the inlet to the outlet of the tap; Figure 5 is a view of a tap according to a further embodiment of the invention; Figure 6 is a view of the tap of Figure 5 in the open condition; Figure 7 is an exploded view of some of the components of the tap of Figures 5 and 6; Figure 8 is a schematic view of a water supply system according to the prior art; and Figure 9 is a view of the water supply system according to one embodiment of the present invention.

Detailed Description of the Preferred Embodiment With reference to the drawings, Figure 1 shows the tap in a disassembled condition. The tap includes a main body 16 which has a water inlet 12 and a water outlet 14. A water flow passage 15 extends through the main valve body between the inlet 12 and the outlet 14. The body 10 has a generally open upper portion 18 which has a screw threaded bore 16. The body 10 also has a main valve seat 20 formed by a shoulder or ledge within the body 10. The main body described above is conventional in design, and therefore no further description is necessary.

According to the preferred embodiment of the invention, the body 10 is provided with a circular recess 22 which receives a cir-clip 24 for providing a ledge or support for a spring 26. Alternatively, a ledge or support could be machined directly onto the body 10. The spring 26 engages an auxiliary valve 30 which has a generally disc shaped body 32 and an upstanding post 34. The body 32 is provided with a shoulder 36 against which the end of the spring 26 mates.

The auxiliary valve 30 also has a valve surface 38 which engages a second valve seat 40 in the valve body 10 and which is formed on a bottom part of the ledge which comprises the main valve seat The stem 34 is provided with a sleeve 42 which is of generally conical or tapered shape in vertical crosssection as seen in Figure 1.

The tap also includes a main valve assembly 50 which includes a bonnet 52 having a screw threaded surface portion 54 for screw thread engagement with the screw threaded bore 16. The bonnet 52 supports a spindle 56 in a manner known per se for rotation relative to the bonnet 52 to raise and lower the spindle, as is also known. The spindle 56 has a tap handle 58 at its outermost end. The spindle 56 also carries a main valve 60 which includes a valve housing 62 which is formed from metal such as brass, and a rubber or like material washer 64.

17 As will be described in more detail hereinafter, the washer 64 engages on the main valve seat 20 to shut off flow of water from the inlet 12 to the outlet 14 when the tap is closed, and is moved away from the valve seat 20 by rotation of the spindle 56 to open the valve to enable water to flow from the inlet 12 to the outlet 14 to provide water from the tap.

The spindle 56, beneath the washer 64, has an integral stem 66 which projects away from the washer 64 as clearly shown in Figure 1.

When the valve is assembled, as is shown in Figure 2, the screw threaded side 54 is screw threaded into the bore 16 as the main valve 50 is screwed down into the bore 16, the stem 66 locates in the sleeve 42. The tapered nature of the sleeve 42 enables the stem 66 to easily find its way into the sleeve and to become self-centring within the sleeve 66 as the bonnet 52 screws down into the bore 16.

When the bonnet 52 is fully screwed down into the bore 16, the engagement of the stem 66 with the recess 42 pushes the auxiliary valve 30 away from the second valve seat 36 against the bias of the spring 26. Thus, when the bonnet 52 is fully assembled on the main body 10, the auxiliary valve 30 is located away from the secondary valve seat 36, thereby not blocking flow of water through the passage 16 between the inlet 12 and the outlet 14.

Figures 3 and 4 show the tap in a fully opened position and a fully closed position respectively. As is conventional, in order to open the tap so that water flows from the inlet 12 to the outlet 14, the tap handle 58 is rotated to in turn rotate the spindle 56 within the bonnet 52. Rotation of the spindle 56 will move the spindle upwardly relative to the bonnet 52, thereby drawing the 18 washer 64 away from the main valve seat 20 and allowing water to pass through the passage 15 to the outlet 14 so water is supplied from the tap. When it is desired to shut off flow of water through the tap, the tap handle 58 is rotated in the opposite direction to drive the spindle 56 downwardly relative to the bonnet 52 so that the washer 64 is moved into engagement with the valve seat 20. When the washer 64 is engaged on the valve seat 20, water is prevented from flowing through the passage 15 from the inlet 12 to the outlet 14, and thus the tap is shut off as is conventional.

As is shown in Figure 4, when the tap is in the closed position, the engagement of the stem 66 in the sleeve 42 pushes the auxiliary valve 30 to an extreme position away from the secondary valve seat 40 and the spring 26 is in a fully compressed condition. The disc shaped body 32 occupies most of the inlet 12 which also serves to reduce flow of water through the passage 15, but does not seat on the main valve body 10. When it is desired to open the tap towards the fully opened position shown in Figure 3, the tap handle 58 is rotated to draw the spindle 56 upwardly in the drawings. As the spindle 56 moves upwardly, the auxiliary valve 30 is pushed upwardly by the spring 26, which maintains the engagement of the stem 66 with the sleeve 42. When the tap is in the fully opened position shown in Figure 3, the auxiliary valve 30 is adjacent to but spaced away from the second valve seat and water is able to flow through the inlet 12 around the auxiliary valve 30 through the passage 15 and out of the outlet 14. Thus, as the tap is adjusted between the fully opened position shown in Figure 3 and the fully closed position in Figure 4, the auxiliary valve 30 moves upwardly and downwardly with the spindle 56 and is guided by and supported by the engagement between the stem 66 and the sleeve 42. This engagement holds the auxiliary valve element 30 in the disposition shown in the drawings 19 without the need for any additional support structure to be formed within the valve body 10. Thus, the valve body can be maintained in its original and standard configuration, apart from the need to locate the cir-clip 24 within the body to merely provide an abutment for one end of the spring 26.

When the washer 64 requires replacement, the bonnet 52 is detached from the tap by unscrewing the screw threaded surface 54 from the screw threaded bore 16. As the bonnet 52 and spindle 56 move upwardly during this unscrewing operation, the spring 26 pushes the auxiliary valve upwardly, maintaining the engagement between the step 66 and the sleeve 42 until the valve surface 38 of the auxiliary valve 30 engages the second valve seat 40 to close the passage 15. Thus, the engagement between the step 66 and sleeve 42 facilitate guiding of the auxiliary valve 30 into the seated position on the second valve seat Continued unscrewing of the bonnet 52 from the body will disengage the stem 66 from the sleeve 42 and enable the bonnet 52 and spindle 56 to be completely detached from the body 10 as shown in Figure 1. The auxiliary valve 30 seated against the valve seat 40 shuts off flow of water through the passage 15 as previously described, and therefore water is not able to pass to the outlet 14 or to the upper opening 18 of the valve body 10. Thus, flow of water is automatically shut off when the bonnet 52 is removed from the tap and therefore it is not necessary to turn off a primary meter valve associated with the premises in which the tap is installed. This therefore enables water to be continuously applied to other taps within the premises without any disruption.

It will be appreciated from the foregoing description that the only support for the auxiliary valve 32 is the 20 engagement between the stem 66 and the sleeve 42. This engagement supports movement of the auxiliary valve during normal use of the tap without the need for any other componentry or elements such as a spider to hold the auxiliary valve 30. Thus, a flow path between the inlet 12 and the outlet 14 through the main body 10 is not reduced in size because of the need for the additional supporting element, and therefore water flow through the tap is not reduced or adversely effect by incorporation of the auxiliary valve assembly. Thus, the flow of water is improved compared to conventional taps which include an auxiliary valve function. Furthermore, because the main valve 70 is fixed to the main valve assembly 50, the number of parts is effectively reduced and disassembly and reassembly of the valve after a pair of the washers 64 is much easier.

In the preferred embodiment of the invention, as is best shown in Figure 1, the washer 64 is housed in the housing 62 and projects only a slight distance beneath the lower extremity 70 of the housing 62. The lower extremity 70 is preferably in the form of an annular wall which defines a space in which the washer 64 locates. The lower extremity forms an abutment and this prevents over-tightening of the valve in the fully closed position because the lower extremity 70 of the housing 60 will bottom out on the valve seat 20 if the spindle 56 is over-tightened, thereby preventing any further movement of the spindle 56 in a downward direction, or compression of the washer 64, to prevent the spindle 56 from jamming and also to reduce wear and immediate damage of the washer 64.

Figures 5 to 7 show a second embodiment of the invention in which like reference numerals indicate like parts to those previously described. The auxiliary valve operates in exactly the same manner as previously described, and therefore its function will not be repeated 21 with reference to Figures 5 and 6. For ease of illustration, the spring 26 which biases the auxiliary valve 30 is not shown in Figures 5 and 6.

In this embodiment, the main valve 60 is provided with an upstanding post 100 which locates in a bore 102 formed in spindle 56. In the embodiment shown, the post 100 is completely separate from the spindle 56 and is able to move relative to the bore 102 and therefore the valve is able to move relative to the spindle 56 and the entire main valve assembly 50, so the parts can be completely separated.

As is shown in Figure 5, a spring 103 is located in the bore 102 of the spindle 56 and a bore 105 in post 100 of the valve 60. The ability to completely remove the post 100 from the bore 102 makes it easy to locate the spring 103 in place, as shown in Figure 5 and the exploded view of Figure 7.

The tap of Figures 5 to 7 operates in exactly the same manner as the embodiment of Figures 1 to 4. If the main valve assembly 52 is completely removed from the tap, the auxiliary valve 30 closes against the auxiliary valve seat as in the earlier embodiment. Figure 6 shows the assembly 52 being removed and the auxiliary valve seating on the auxiliary valve seat In normal operation of the tap, the handle 58 is rotated to raise the spindle 56 so the main valve 60 can move away from the main valve seat 20. Water pressure at the inlet 12 will push the main valve upwardly against the bias of the spring 103 so the post 100 remains fully inserted into the bore 102 and the spring 103 slightly compressed.

Thus, in normal operation with proper mains pressure, the tap operates in exactly the same manner as the previous embodiment, as if the main valve 60 was fixed to the 22 spindle 56 as in the earlier embodiment. However, in this embodiment, if the pressure at the mains side of the tap drops for some reason, the spring 103 will then be able to bias the main valve 60 away from its open position back towards the main valve seat 20 with the post 100 sliding in the bore 102 so the main valve 60 again seats on the seat 20. This will prevent backflow of water from the inlet 14 towards the outlet 12 and back to the mains side of the tap. Thus, the tap of this embodiment provides a check valve function as well to prevent backflow of water in the event of loss of mains pressure on the mains side of the tap. It will be understood that the size of the post 100 and the bore 102 is such that the maximum amount of movement of the valve 60 from the fully open position back into engagement of the seat 20, does not completely remove the post 100 from the bore 102 so the valve 60 is guided by the engagement of the post 100 and the bore 102 so that when the main pressure is again re-established, the valve 60 will be pushed away from the seat with the post 100 returning to the fully inserted position within the bore 102 and the spring 103 again compressing.

In this embodiment, when the valve 60 is removed for replacement, the spindle 56 and main valve 62 separate from one another. The provision of the valve 62 and spindle 56 as separate parts enables easy installation and location of the spring 103 during initial assembly.

However, in other embodiments, the post 100 could include a lug (not shown) and the side of the bore 103 a groove so that the lug locates in the groove and the groove is then closed at the lower end of the spindle 56 so that, although the post 100 can move in the bore 102, it cannot completely release. This will therefore enable the spindle 56 and main valve 60, together with the spring 103, to remain as a connected unit, thereby making disassembly and reassembly of the valve as easy in the first embodiment of the invention.

23 In the embodiment of Figures 1 to 4 the engagement between the main valve assembly 50 and the auxiliary valve 30 is by way of a generally cone shaped or tapered stem 66 which sits in a corresponding shaped recess 42. This engagement provides the support for the auxiliary valve 30 so that the flow passage of the tap is not blocked by the need to provide other support such as the spider previously mentioned. However, it should be understood that in this embodiment the spring 26 also supplies some support to the auxiliary valve 30 to hold the auxiliary valve 30 aligned and prevent the auxiliary valve 30 from moving laterally because of the cone shaped stem 66 and recess 42. Thus the total support in the embodiment of Figures 1 to 4 is by virtue of the engagement between the stem 66 and the recess 42 and the spring 26. However, it should be understood that the support provided by the stem 66 and the recess 42 avoids the need for a spider or other elements which would block the flow passage and therefore there is no need to provide other support which would otherwise block the flow passage and therefore reduce flow characteristics of water through the tap. In the embodiment of Figures 5 to 7, as is best seen in Figure 7 the stem 66 is in the form of a generally cylindrical stem which seats into a cylindrical recess 42. The shape of this stem and recess provides lateral support so that if desired the sole and total support for the auxiliary valve can be provided by the engagement of the stem 66 in the recess 42. In this embodiment the spring 26 could be completely done away with because water pressure will serve to move the auxiliary valve 30 to shut off flow when the main valve is removed from the tap in the manner previously described. Since the stem 66 is cylindrical as is the recess 42 this provides lateral support so that stabilising support via a spring 26 or the like is not required. In the preferred embodiment the spring 26 is used because it provides additional bias to move the auxiliary valve 30 into its required position to ensure 24 that it does operate properly.

If the spring 26 is done away with it is desirable to make the stem 66 and the recess 42 of sufficient size that the stem 66 and the recess 42 will not disengage during movement of the valve 60 and auxiliary valve 30 in normal operation of the valve. However, when the bonnet 52 is removed from the housing 10 the main valve 60 can be lifted away from the auxiliary valve 30 by simply disengaging the stem 66 from the recess 42 in a separate operation.

Figure 8 is a schematic view of a water supply system used in many environments such as for supply of water to buildings, dwellings and the like. Regulations require that such systems often include two check valves to prevent backflow of water from an inlet side of the system to the main side of the system. The two valve are provided to provide failsafe operation in the event of one valve failing for some reason. Typically, such systems include a water supply pipe 120, which is connected to a mains supply (not shown). The supply pipe 120 is connected to a water pipe leading to the building or the like on outlet side 121 of the system. Typically, the pipe 120 is of U-shaped configuration and is arranged above the ground, whereas the remaining of the plumbing is below ground. The pipe 120 may be contained in a housing or the like not shown. The supply pipe 120 includes a check valve housing 124 in which two check valves schematically shown at 125 and 126 are included to prevent backflow from outlet side 121 to mains side 122. A tap 130 is provided usually on the outlet side for shutting off supply of water through the pipe 120 if desired.

Figure 9 is a schematic arrangement of one embodiment of the invention in which like reference numerals indicate like parts to those described with reference to Figure 8.

25 In this embodiment the housing 124 contains only one check valve 125. The other check valve is provided in tap 130' which is configured in exactly the same manner as described with reference to Figures 5 to 7, except that the outlet 14, rather than being in the form of a spout or the like, is connected in the pipe 120. Thus, in this embodiment, the second check valve function is provided by the tap 130' by virtue of the arrangement described with reference to Figure 7. Thus, this embodiment still provides the dual check valve function which provides the failsafe operation, but enables the housing 124 to be reduced in size, thereby simplifying the housing and reducing costs. This embodiment also provides the advantage of the tap including the auxiliary valve configuration so that repair and maintenance can be performed on the valve 60 whilst the auxiliary valve shuts off flow of water as in the earlier embodiments.

Since modifications within the spirit and scope of the invention may readily be effected by persons skilled within the art, it is to be understood that this invention is not limited to the particular embodiment described by way of example hereinabove.

In the claims which follow and in the preceding description of the invention, except where the context requires otherwise due to express language or necessary implication, the word "comprise", or variations such as "comprises" or "comprising", is used in an inclusive sense, ie. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the invention.

Claims (28)

1. A tap comprising: a main valve body having a water inlet and a water outlet and defining a flow passage through the body between the inlet and the outlet; a main valve seat located between the inlet and. the outlet; a main valve having a washer for engaging the seat and moveable from a first position allowing water to flow from the inlet to the outlet, to a second position shutting off flow of water from the inlet to the outlet; a control assembly attached to the main valve for moving the main valve between the first and second positions; a first coupling and support portion on the control assembly; an auxiliary valve and an auxiliary valve seat within the tap, the auxiliary valve having a second cooperating coupling and support portion for engaging the first coupling and support portion so the auxiliary valve is supported within the main body by the control assembly without any additional support which would reduce the size of the flow passage; and wherein when the control assembly is attached to the tap, the coupling and support portions couple and engage with one another so as to push the auxiliary valve away from the second valve seat, and provide support to the auxiliary valve, so that when the control assembly is actuated to move the valve to the second position water is able to flow passed the auxiliary valve and second valve seat to the outlet, and when the control assembly is detached from the tap to allow replacement of the washer, the control assembly and valve separate from the valve body as a single unit, the first coupling and support portion is separated from the second coupling and support portion, and the auxiliary valve is able to move to seat 27 against the second valve seat to shut off flow of water to the outlet.

2. The tap of claim 1 wherein biasing means is provided for biasing the auxiliary valve towards the second valve seat so that when the control assembly is attached to the tap the coupling and support portions couple and engage with one another to push the auxiliary valve away from the second valve seat against the bias of the biasing means.

3. The tap of claim 1 wherein the control assembly includes a valve bonnet releasably couplable to the main body, the valve bonnet supporting a spindle for rotation relative to the bonnet, the spindle carrying the main valve and washer so that upon rotation of the spindle, the spindle and main valve and washer move away from the valve seat to allow water to flow from the inlet to the outlet, and upon rotation of the spindle in the opposite direction, the valve and washer are moved toward the main valve seat to engage the main valve seat to shut off flow of water from the inlet to the outlet.

4. The tap of claim 1 wherein the engagement of the first and second coupling and support means supports the auxiliary valve for movement between an extreme position away from the second valve seat when the main valve is seated on the main valve seat, and a position adjacent to the secondary valve seat, but spaced from the secondary valve seat, when the main valve is in the second position away from the main valve seat. The tap of claim 2 wherein the biasing means comprises a spring.

6. The tap of any one of claims 1 to 5 wherein the auxiliary valve has a circumferential shoulder for 28 engaging the spring.

7. The tap of claim 6 wherein the main body has an abutment for supporting the other end of the spring.

8. The tap of any one of claims 1 to 7 wherein the first coupling and support portion comprises a stem on the spindle and the second coupling and support portion comprises a sleeve in the auxiliary valve, so that the stem locates in the sleeve to support and guide movement of the auxiliary valve between the extreme and adjacent positions without additional structural support within the main valve body.

9. The tap of any one of claims 1 to 7 wherein the auxiliary valve has a generally disc shaped body including the shoulder and an upwardly extending post section which includes the sleeve.

10. The tap of any one of claims 1 to 9 wherein the auxiliary valve is also supported by the biasing means.

11. A main valve assembly for a tap which includes an auxiliary valve seatable on a second valve seat to shut off flow of water through the tap when the main valve assembly is removed from the tap for repair, the assembly comprising: a bonnet for releasable connection to the tap; a spindle arranged in the bonnet for rotation relative to the bonnet; a main valve including a valve washer attached to the spindle for movement with the spindle to move the valve upon actuation of the spindle from a first position which allows water to flow through the tap to a second position which will prevent flow of water through the tap; a first coupling and support portion on the valve assembly for engaging and supporting the auxiliary valve 29 when the main valve assembly is attached to the tap so the first coupling and support portion guides and supports movement of the auxiliary valve between an extreme position away from the second valve seat and an adjacent but spaced position away from the second valve seat when the spindle is moved to open and close the tap, and when the main valve assembly is detached from the tap to allow repair or replacement of the valve assembly, the first coupling and support portion disengages from the auxiliary valve so the auxiliary valve can move into a position against the second valve seat to shut off flow of water through the tap; and wherein the engagement of the coupling and support portion with the auxiliary valve provides support for the auxiliary valve so that a flow path through the tap from an inlet of the tap to an outlet of the tap is not reduced by the need for other supporting elements to support the auxiliary valve.

12. The main valve assembly of claim 1 wherein the first coupling and support portion comprises a stem on the spindle for engaging with a second coupling and support portion comprised of a sleeve on the auxiliary valve so that the stem locates in the sleeve to support and guide movement of the auxiliary valve between the extreme and adjacent positions without additional structural support within the valve body.

13. An auxiliary valve for a tap which has a main valve assembly moveable relative to a main valve seat to selectively allow water to flow from an inlet of the tap to an outlet of the tap, the tap having a second valve seat, the auxiliary valve comprising: a valve body for engaging the second valve seat to shut off water through the tap when the main valve assembly is removed from the tap to allow repair or replacement of the main valve assembly; 30 a second coupling and support means on the auxiliary valve for engaging the main valve so the auxiliary valve is supported by the main valve when the main valve is moved from a first position allowing water to flow through the tap, to a second position shutting off flow of water through the tap, whereupon during which movement the auxiliary valve is supported for movement between an extreme position away from the second valve seat to a position adjacent to but spaced from the second valve seat, and whereupon when the main valve assembly is removed from the tap, the second coupling and support means disengages from the main valve to allow the auxiliary valve to move into contact with the second valve seat to shut off flow of water through the tap; and wherein the engagement between the second coupling and support means and the main valve provides the only support for the auxiliary valve so that additional supporting elements are not required in a flow path in the tap between an inlet of the tap and an outlet of the tap so the size of the flow path is not reduced by any other support element.

14. The auxiliary valve of claim 13 wherein the auxiliary valve has a circumferential shoulder for engaging a spring when the auxiliary valve is assembled in the tap. The auxiliary valve of claim 13 or 14 wherein the second engaging and coupling means comprises a sleeve in the auxiliary valve and the main valve has a first coupling and support portion comprised of a stem so that the stem locates in the sleeve to support and guide movement of the auxiliary valve when assembled in the tap between the extreme and adjacent positions without additional structural support within the valve body.

16. The auxiliary valve of any one of claims 13 to 31 wherein the auxiliary valve has a generally disc shaped body including a shoulder and an upwardly extending post section which includes the sleeve.

17. A tap which includes a main valve seat, comprising: a spindle mounted for rotation in the assembly to selectively open and close the tap; a main valve supported on the spindle for movement with the spindle so as to move the valve between an open position and a shut off position; the main valve including a valve support having at least one abutment portion; and a resilient, substantially flat washer supported by the valve support and projecting beyond the abutment so that when the spindle is operated to close the valve by moving the washer to seat against the valve seat, the abutment prevents over-tightening and jamming of the main valve assembly by abutting on the valve seat to thereby limit the amount of compression of the resilient washer and movement of the spindle toward the valve seat.

18. The tap of claim 17 wherein the support comprises a housing and the abutment portion comprises a generally annular wall which defines a space into which the washer locates.

19. A tap comprising: a main valve body having a water inlet and a water outlet; a main valve seat located between the inlet and the outlet; a main valve having a washer for engaging the seat and moveable from a first position allowing water to flow from the inlet to the outlet, to a second position shutting off flow of water from the inlet to the outlet; a control assembly coupled to the main valve for 32 moving the main valve between the first and second positions, the main valve being moveable relative to the control assembly; a spring disposed between the control assembly and the main valve assembly for biasing the main valve assembly towards the valve seat; a first engaging portion; an auxiliary valve and an auxiliary valve seat within the tap, the auxiliary valve having a second engaging portion for engaging the first engaging portion; and wherein when the control assembly is attached to the tap, the engaging portions engage with one another so as to push the auxiliary valve away from the second valve so that when the control assembly is actuated to move the valve to the second position, water is able to flow passed the auxiliary valve and second valve seat to the outlet, and when the control assembly is detached from the tap to allow replacement of the washer, the auxiliary valve is moved to seat against the second valve seat to shut off flow of water to the outlet; and wherein when the main valve is away from the main valve seat and water pressure at the inlet of the valve reduces, the spring biases the main valve relative to the control assembly so the main valve is biased into engagement with the main valve seat to provide a check valve function to prevent backflow of water from the outlet side of the tap to the inlet.

20. The tap of claim 19 wherein the control assembly includes a valve bonnet releasably couplable to the main body, the valve bonnet supporting a spindle for rotation relative to the bonnet, the spindle carrying the main valve and washer so that upon rotation of the spindle, the spindle and main valve and washer move away from the valve seat to allow water to flow from the inlet to the outlet, and upon rotation of the spindle in the opposite 33 direction, the valve and washer are moved toward the main valve seat to engage the main valve seat to shut off flow of water from the inlet to the outlet.

21. The tap of claim 19 wherein the engagement of the first and second engaging portions supports the auxiliary valve for movement between an extreme position away from the second valve seat when the main valve is seated on the main valve seat, and a position adjacent to the secondary valve seat, but spaced from the secondary valve seat, when the main valve is in the second position away from the main valve seat.

22. The tap according to any one of claims 19 to 21 further including biasing means for biasing the auxiliary valve towards the second valve seat so that when the engaging portions engage to push the auxiliary valve away from the second valve seat, the auxiliary valve is pushed against the bias of the biasing means, and when the control assembly is detached from the tap to allow replacement of washer, the biasing means biases the auxiliary valve to seat against the second valve seat.

23. The tap according to any one of claims 19 to 22 wherein the first engaging portion comprises a first coupling and support portion and the second engaging portion comprises a second coupling and support portion which support the auxiliary valve without the need for additional support which would reduce the size of the flow passage through the tap.

24. The tap of claim 22 wherein the biasing means comprises a spring.

25. The tap of claim 19 wherein the auxiliary valve has a circumferential shoulder for engaging the spring. 34

26. The tap of claim 19 wherein the main body has an abutment for supporting the other end of the spring.

27. The tap of claim 23 wherein the first coupling and support portion comprises a stem on the spindle and the second coupling and support portion comprises a sleeve in the auxiliary valve, so that the stem locates in the sleeve to support and guide movement of the auxiliary valve between the extreme and adjacent positions without additional structural support within the main valve body.

28. The tap of claim 27 wherein the auxiliary valve has a generally disc shaped body including the shoulder and an upwardly extending post section which includes the sleeve.

29. A water supply system comprising: a water supply pipe; a housing in the water supply pipe and having a first check valve for preventing backflow of water from an outlet side of the water supply system to a mains side of the water supply system in the event of a reduction in pressure at the mains side; a tap in the water supply side spaced from the housing, the tap having: a main valve; a main valve seat; a control assembly for moving the main valve between a first position away from the main valve seat and a second position in engagement with the main valve seat to selectively allow flow of water through the supply pipe and tap, or shut off flow of water through the tap; a check valve within the tap for closing flow of water through the tap in the event of reduction of water pressure on the mains side to thereby provide a second check valve for preventing backflow of water from the outlet side to the mains side. 35 The system of claim 29 wherein the check valve comprises the main valve, the main valve being arranged for movement relative to the control assembly, a spring disposed between the control assembly and the main valve for biasing the main valve towards the main valve seat so that when normal pressure exists and the tap is open, water pressure pushes the valve seat against the bias of the spring to thereby maintain the main valve away from the valve seat to allow flow of water through the tap, but if there is a reduction in pressure at the mains side, the spring biases the main valve relative to the control assembly so the main valve is moved into engagement with the main valve seat to prevent backflow of water from the outlet side of the tap to the mains side.

31. A tap substantially as hereinbefore described with reference to the accompanying drawings. Dated this 21st day of October 2003 ROSS SHILTON By their Patent Attorneys GRIFFITH HACK Fellows Institute of Patent and Trade Mark Attorneys of Australia