GB2209816A

GB2209816A - Fluid flow control valve and a flushing system incorporating such a valve

Info

Publication number: GB2209816A
Application number: GB8819881A
Authority: GB
Inventors: Robert Anthony Brown
Original assignee: Individual
Current assignee: Individual
Priority date: 1987-09-15
Filing date: 1988-08-22
Publication date: 1989-05-24
Anticipated expiration: 2008-08-22
Also published as: GB8819881D0; GB8721689D0; GB2209816B

Abstract

A flushing system for a urinal (16) comprises a fluid flow control valve (12, 60) in a pressurised water supply line, an outlet of the valve feeding a tank (15) for delivering flushing water to the urinal (16), and a capillary tube (19) containing fluid and having a temperature sensing part in a waste trap (17) of the urinal. Expansion and contraction of the fluid in the temperature sensing part causes expansion and contraction of a bellows (20) arranged in the valve between a fixed (21) and a movable part (22) thereof. In use, the temperature of the urine is sensed by the sensing part, with the result that the bellows expand and moves the movable part of the valve away from the fixed part, thereby lifting a valve member (30) off its valve seat and allowing a flow of water to the tank to flush the urinal. The sensed temperature then falls and the valve closes. Thus in this application of the invention, flushing occurs only when the urinal is actually used. The valve includes a permanent feed device constituted by a bore (47) and pin (48). The tank (15) and permanent feed device may be omitted. <IMAGE>

Description

FLUID FLOW CONTROL VALVE AND A FLUSHING SYSTEM INCORPORATING SUCH A VALVE This invention relates to a fluid flow control valve and a flushing system incorporating such a valve, the flushing system being for a urinal.

At present, one such flushing system employs an arrangement where flushing occurs at regular intervals.

A trickle cock is provided in the water supply pipe to a cistern connected to the or each urinal, so that the cistern automatically and regularly fills and then flushes, each time being refilled by water passing through the trickle cock. Obviously, therefore, the flushing which occurs is unrelated to any actual use ofthe urinals served by the cistern. Thus for urinals, for example in factories or offices, there will be particular times of non-use, such as at night or at holiday periods, where the flushing will automatically continue unnecessarily, with a consequential waste of water.

Another such automatic flushing system employs a valve which opens to allow flow of water to a cistern connected to the or each urinal if a pressure drop occurs at the valve. In this system the water supply typically also feeds to a wash basin and/or a manual flush toilet, so that a turning on of the cold tap of the basin or the flushing of the toilet, will create a pressure drop at the valve which will open it, allowing water to be fed to the cistern which will flush the or each urinal. Although more satisfactory than the first system described, it is considered that this system also wastes water, as flushing of the urinals is not necessarily as a result of their use, but can be merely as a result of the use of the ancillary water-using facilities which utilise the same water supply.

An object of the invention is to provide an improved flushing system and a further object is to provide an improved fluid flow control valve for use in such a system.

According to the present invention there is provided a flushing system for a urinal, comprising a fluid flow control valve having an inlet and an outlet, a valve member and a co-operating seat, the valve seat defining an opening which is opened or closed by movement of the valve member, the opening, when open, communicating the inlet with the outlet, the valve member normally being held on its seat by means of a biasing force, the valve inlet being intended to be connected, in use, to a pressurised water supply, the valve outlet communicating with a reservoir feeding a member for flushing a urinal or communicating directly with said member, and the valve incorporating a sensing unit having a temperature sensing part arranged at the urinal or in an outlet path therefrom, and a further part at the valve, so that dependent upon the temperature sensed by the sensing part, in use, the valve member moves off its seat to allow water to flow, in use, through said opening, from the inlet to the outlet.

According to a further aspect of the present invention there is provided a fluid flow valve comprising an inlet and an outlet, a valve member and a co-operating seat, the valve seat defining an opening which is opened or closed by movement of the valve member, the opening, when open, communicating the inlet with the outlet, the valve member normally being held on its seat by means of a biasing force, there being provided a sensing unit having a temperature sensing part outside of the valve and a further part at the valve, so that dependent upon the temperature sensed by the sensing part, in use, the valve member moves off its seat to allow fluid to flow, in use, through said opening, from the inlet to the outlet.

As used herein the term 'fluid' includes both a gas and also a liquid.

The invention will now be described, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a diagrammatic view of an automatic flushing system of the invention, Figure 2 is a cross-sectional view of a fluid flow control valve of the flushing system of Figure 1, Figure 3 is a cross-section of an alternative form of fluid flow control valve of the flushing system of Figure 1, and Figure 4 shows the alternative view from one side.

Shown in Figure 1 is an automatic water flushing system for a conventional urinal, there being an inlet pipe 10 supplying pressurised cold water to an inlet 11 of a fluid flow control valve 12. From an outlet 13 of the valve is connected an outlet pipe 14, which extends via a syphon tank 15 to the top of a urinal 16 in order to supply, as will be described, flushing water to the urinal only after each occasion of use. At the bottom of the urinal there is connected a conventional U-bend or waste trap 17 connected to a waste pipe 18.

The valve 12 is provided with remote sensing means, to which it is connected by a capillary tube 19. The sensing means is a metallic bulb, one end of which is closed by a brass plug, soldered to the bulb. The tube 19 passes centrally through the plug to communicate with the interior of the bulb and is itself soldered to the plug. The upper end of the tube 19 is received into the top of the valve, as will be described hereinafter, with the main part of the tube extending downwardly in the manner schematically shown, for the bulb to be installed in the waste trap 17. Preferably the sensing means is made from a material which will not be corroded by products received in the waste trap.The tube 19 extends through, and is soldered to, a flanged brass end fitting 57 at the top of the valve, to communicate with the interior of a metallic bellows 20 (Figure 2), the top of which is soldered to the flange of the fitting. The complete assembly of bellows, tube and sensing means is hermetically sealed and filled with liquid or gas. Accordingly variations in temperature at the bulb will cause the liquid or gas in the tube 19 to expand or contract, resulting in a change in pressure within the bellows. The sensing unit thus comprises the bellows, the metallic bulb and the capillary tube which interconnects them.

The valve 12 is shown in detail in Figure 2. It has a body part 21 and an adjustment part 22. The body part, which is made, for example, of brass, is of inverted T shape, having the valve inlet 11 and the valve outlet 13 in axial alignment at respective opposite sides of a generally central chamber 23 in the longer limb of the T-shaped part 21.

Between the inlet and outlet is a wall 24, and the top of this, with a further wall of the part 21 forms an upwardly directed, annular seat which defines a circular opening. This opening is internally screw-threaded at its top and screwed into the opening is a headed phosphor-bronze screw 25 with its head 26 received on the seat. The screw 25 has a central, circular bore 27 extending from its lower surface, this opening into a larger central, circular bore 28 formed in the upper surface 29 of the screw. The annular surface 29 around the bore forms a valve seat for a circular rubber washer 30 at the end of a valve member 31.

The longer limb of the body part is made up of a lower part, integral with the valve inlet and the valve outlet, and containing the chamber 23, and an upper part 32. The lower part terminates upwardly in an outwardly extending radial flange 33 which is externally screw-threaded. The part 32 is of generally hollow cylindrical form with its upper end closed by a wall 34. Its lower end is closely received into the chamber 23 of said lower part, with an outwardly extending radial flange 35 of the part 32 engaging on the axially, outwardly facing surface 36 of flange 33, an O-ring seal 37 in an annular groove in the surface 36 being compressed by the flange 35. The flange 35 is externally threaded so that the lower and upper parts of the longer limb of the body part 21 can be engaged and sealed together by a nut 38 engaged on the screw threads of the flanges 33 and 35.

The valve member 31 has, at its lower end, a head of an outer diameter such that it can slide as a close fit in the part 32, with an 0-ring seal 39 in an annular groove in the periphery of the valve member sealing against the inside of part 32. Above this groove, the valve member is stepped inwardly to form a stem 40.

Above its flange 35, the part 32 is internally inwardly stepped so that from this step up to the wall 34 there is defined a hollow cylindrical part 41 in which the stem 40 is a close sliding fit. Between the step on the valve member and the step in the part 32 is a coiled compression spring 42 disposed around the stem, the spring thus forcing the valve member downwardly.

The head of the valve member 31 has a central, circular bore 43 extending inwardly from its lower end. A further bore 44 at 900 to bore 43 extends from the bore 43 to the peripheral side surface of the head. The bore 43 is screw-threaded at its lower end, the threading terminating at approximately the level where the bore 44 breaks into the bore 43. Threadedly engaged in the bore 43 is a further, headed phosphor-bronze screw 45 which extends through a central bore in washer 30. The screw head 46 bears against a lower surface of the washer 30 to hold the washer against the bottom of the valve member head. The screw 45 has a circular section bore 47 centrally through it, and extending through the bore 47 with clearance is a phosphor-bronze pin 48.An enlarged head of the pin is received in the bore 43 above the upper end of the screw 45 and this head prevents the pin dropping out of the screw 45.

At its upper end, the stem 40 has a stainless steel pin 49 diametrically through it, the pin being secured thereto by adhesive. The ends of the pin extend through respective slots 50, 51 in the part 32 adjacent the wall 34, and engage in respective circular holes 52 in the end of the adjustment part 22.

In the position shown in Figure 2, the valve 12 is closed, with the part 22 in its lowest position, the spring 42 forcing the washer 30 onto the valve seat 29.

The head 46 of screw 45 is received in the bore 28 and the pin 48 extends through the bore 27 with clearance.

Thus in this closed position there is no main flow of water from the inlet 11 to outlet 13 due to the washer 30 covering bore 28. However a minute secondary feed is provided in that a restricted flow of water can occur through bore 27 around pin 48, into bore 28, through bore 47 around pin 48, into bore 43 and out through bore 44 into a passage 53 leading into outlet 11. A trickle of water can thus be supplied to the tank 15 so that periodic flushing, for example every 12 hours, can occur. This secondary feed facility is primarily intended for an installation where there are several urinals and could be omitted if there was only one or two. In this case the bore 44 would be omitted. Accordingly the washer 30 would seal down onto the valve seat 29 and prevent any flow of water from the inlet 11 to outlet 13.

The part 22 is a generally hollow cylinder, open at its upper and lower ends and having its upper end externally screw-threaded. The top of the upper part 32 is received in the cylinder and the arrangement is that the part 22 can move relative to the part 32 from the closed position of the valve 12 shown in Figure 2, to a position where the pin 49 engages the upper ends of the slots 50, 51 respectively and the washer 30 is thus raised clear of the valve seat 29 to allow full flow of water from the inlet, through bores 27 and 28 and through chamber 23 and passage 53 to the outlet.

On the threaded end of the part 22 is a lock nut 54, and a flanged adjusting nut 55 which partly closes the top of the valve but has a central circular hole 56 therethrough. The capillary tube 19 is sealingly received through the end fitting 57, the main body of which passes through the hole 56, and, with clearance, through a split ring 58 abutting the underside of the flange of the nut 55 and the top of the flange of fitting 57. The bellows 20 is thus held between the ring 58 and wall 34. Accordingly when the temperature sensed at the remote sensor at the end of the tube 19 exceeds a predetermined set value, the liquid or gas therein expands and this is converted into an expansion of the gas or liquid in the bellows.Thus the expansion acts to force the ring 58 and wall 34 apart, and since the wall 34 is fixed, the expansion raises part 22 which, by way of the pin 49, raises the valve member off its valve seat against the force of spring 42. When the temperature sensed begins to fall, the liquid or gas contracts, the bellows contract and the valve closes under the return force of spring 42.

It will be appreciated that adjustment of the adjusting nut 55 will alter the temperature at which the valve will open and close, since it varies the distance between the ring 58 and wall 34, i.e. the volume of the bellows. Typically the nut is set so that the valve opens at 23/250C, depending on water pressure. Also typically the movement of the bellows is 0.l-0.lSmm/10C.

Thus in use, the valve 12 is normally held closed as the sensor of the tube 19 senses a temperature below the pre-set temperature at which it causes the expansion of the bellows to overcome the force of the spring 42. As explained, however, if the secondary feed facility is provided a flush every 12 hours or so occurs irrespective of the sensor.

When the urinal is used, the sensor senses the temperature of the discharged urine which passes into the waste trap 17. The temperature of the urine will be at approximately body temperature, i.e. 350C, and the sensing of this increased temperature causes expansion of the gas or liquid in the tube 19, resulting in an expansion of the bellows 20 and an opening of the valve as described. Water thus flows from the outlet 13, through the outlet pipe 14 to the tank 15, and then to the urinal 16 where the bowl is flushed and the water passes through the waste trap carrying away the urine to the waste pipe. Thus the urinal is hygienically flushed with minimum use of water, as once the urine is flushed away, the temperature sensed by the sensor falls sufficiently for the bellows to be contracted by an amount which allows the valve to close.Once the flow of water is cut off to the outlet pipe, the tank can no longer supply flushing water to the urinal. Further flushing, other than by the secondary feed, will not occur until the sensor again senses a sufficiently increased temperature in the waste trap 30, and thus a great saving in the amount of water used can be made.

With an approximate urine temperature of 350C and an approximate maximum water temperature of 200C, the valve could be set to open at 230C. At a water pressure of 27.58 x 104 N/m2 (401b/in2) a flow rate of approximately 3g/hr could be expected. As mentioned adjustment of the temperature at which the valve opens can take place by screwing the nut 55 up or down.

Instead of the arrangement of Figure. 2 where the tank automatically provides a flush when it is full,. the valve 12 could instead merely be incorporated in a pressurised cold water supply line leading to the urinal, so that there would be a direct flush from the inlet pipe, through the valve, to the outlet pipe and then to the urinal each time the sensor detected use of the urinal. With this arrangement the secondary feed would not be necessary and bore 44 and pin 48 in Figures 2 and 3 would be omitted.

Figures 3 and 4 show an alternative embodiment of the valve 12. This valve 60 is generally similar in construction and operation to the valve 12 of Figure 2, the main difference being that the adjustment part 22 is integral with the valve member and as the slots 50, 51 are now in the part 22 and the pin 49 fixed to the body part, the pin 49 stays stationary relative to the slots instead of the other way round as previously.

The lower part of the valve 60 is effectively the same as for valve 12 and will thus not be described. The same reference numerals have been used to indicate identical parts.

The longer limb of the body part of the valve has an upper part denoted by the numeral 61 and is similar to part 32 in being of generally hollow cylindrical form.

However it is of constant interior cross-section with both its ends open. Its lower end is externally screw-threadedly engaged on the lower part of the longer limb of the body part. A flange 62 on the part 61 is sealed onto the flange 33 of the lower body part by an O-ring 63.

A valve member 64 of the valve 60 has the same lower end as for the valve member 31, but its upper part is an open-ended, hollow cylinder which extends out of the top of the part 32. Adjacent the top of part 61 the pin 49 has its respective ends received in circular holes 65, 66 in the part 61. The pin passes through respective slots 67, 68 in the valve member 64 and through a circular block 69 which thus forms a fixed part of the valve with the upper part 61. Thus the valve member 64 can slide up and down between the part 61 and block 69.

The top of the integral valve member corresponds exactly to the equivalent adjustment part of valve 12.

However the bottom of the bellows bears on an upper flat surface of the block 69, whilst the spring 42 fits between a lower flat surface of the block 69 and an inner upper surface of the head of the valve member.

As will be apparent, operation of the valve 60 is effectively the same as for valve 12 in that a rise in temperature is sensed by the remote capillary tube sensor bulb and if the sensed temperature is above the set temperature it causes the bellows to expand to increase the distance between the ring 58 and the block 69. Thus as the block is fixed relative to the valve body, the adjustment part and integral valve member rise, thus lifting the washer 30 off its seat and allowing the main flow of water.

Instead of a specially constructed valve as shown in Figure 2 or Figure 3, it is also possible to adapt a conventional thermostatically controlled radiator valve, which is of the normally held open type. This valve has a valve seat between an inlet and an outlet.

A valve member is normally held off said seat, but when a sensor of the valve senses a rise in temperature it is moved by expansion of gas or liquid onto the valve seat to close the valve. To convert this valve to a normally closed one, an adaptor is fitted between a lower body part of the valve, containing the inlet and outlet, and an upper adjustment part of the valve.

The adaptor has a hollow, generally cylindrical housing part which is closed at its upper end and open at its lower end, which is sealingly engaged to the body part of the valve. Adjacent this lower end the housing part has a pair of diametrically opposed slots. At its closed end an outward, upward projection is formed.

The housing part has a sliding cylindrical sleeve around it. Near one end the sleeve has a pair of diametrically opposed holes and at its other end it is sealingly connected to the upper adjustment part of the valve. Within the housing part is a spring which acts between the housing part and a valve member actuating element which is a close sliding fit in the housing part and has a through bore. A pin extends through the valve member actuating element, with the opposite ends of the pin extending through the slots and into the holes, where they are secured to the sleeve.

The valve member actuating element is thus biased towards the open end of the housing and acts upon a valve member to force it onto its valve seat. However if the capillary tube sensor senses a rise in temperature at the waste trap, it causes expansion of the liquid in the tube. The tube extends into a top part of the valve where a suitable liquid, or a gas, such as Freon, is contained, and the expansion of the liquid is arranged to expand the Freon to cause an actuating member to press down on the projection at the closed end of the housing. However since the housing is fixed, this causes upward movement of the upper, adjustment part of the valve together with the sleeve which is connected to it.As the sleeve moves it raises the valve member actuating element against said spring, and this thus releases the upwardly biased valve member from its seat to allow fluid flow from the valve inlet to the valve outlet through the valve seat opening. Thus the form of this adapted valve is somewhat like the valve 12 of Figure 2.

Other thermostatically controlled valves could of course be used in place of those described, provided they operate to flush a urinal following the use thereof.

The sensor part of the valve could be arranged at any suitable part of the urinal and need not necessarily be in the waste trap 17, provided it is able to sense the increase in temperature which occurs when the urinal is used.

For an installation with more than one urinal bowl, a common trap could be used, so that the valve would operate irrespective of which bowl was being used.

However if Building Regulations prevented such an arrangement, the sensing part would be disposed under one of the bowls, so that the valve would only open when the selected bowl is used. All the bowls could then be flushed.

Claims

1. A flushing system for a urinal, comprising a fluid flow control valve having an inlet and an outlet, a valve member and a co-operating seat, the valve seat defining an opening which is opened or closed by movement of the valve member, the opening, when open, communicating the inlet with the outlet, the valve member normally being held on its seat by means of a biasing force, the valve inlet being intended to be connected, in use, to a pressurised water supply, the valve outlet communicating with a reservoir feeding a member for flushing a urinal or communicating directly with said member, and the valve incorporating a sensing unit having a temperature sensing part arranged at the urinal or in an outlet path therefrom, and a further part at the valve, so that dependent upon the temperature sensed by the sensing part, in use, the valve member moves off its seat to allow water to flow, in use, through said opening, from the inlet to the outlet.

2. A system as claimed in claim 1, wherein said sensing part contains a fluid which expands and contracts as the temperature sensed by said sensing part changes.

3. A system as claimed in claim 2, wherein the sensing part is connected to the valve by a capillary tube, expansion or contraction of the fluid in the sensing part and the capillary tube being arranged to produce a variation in force acting between respective fixed and movable parts of the valve.

4. A system as claimed in claim 3, wherein said force is provided by a bellows acting between said fixed and movable parts of the valve.

5. A system as claimed in claim 4, wherein said force of the bellows is opposed by said biasing force, said force overcoming said biasing force and moving said valve member off its valve seat when said temperature sensing part of the sensing unit senses a temperature equal to or greater than a predetermined temperature.

6. A system as claimed in claim 5, wherein the fixed part of the valve is a body part defining the inlet, the outlet and the valve seat, and the movable part is an adjustment part containing said bellows.

7. A system as claimed in claim 6, wherein one of said fixed and movable parts carries a pin which extends through opposed slots in respective opposite sides of the other of said fixed and movable parts.

8. A system as claimed in claim 7, wherein the pin is carried by the movable part and extends through a stem of the valve member, the slots are in the fixed part and the biasing force is provided by a spring acting between a head of the valve member and said fixed part, so that when the bellows expand said adjustment part and the valve member are moved together away from the valve seat to compress the spring and open the opening in the valve seat to allow water to flow therethrough from the inlet to the outlet.

9. A system as claimed in claim 7, wherein the pin is carried by the fixed part and extends through an end member to secure it to the fixed part, the slots are in the movable adjustment part, with which the valve member is integral, and the biasing force is provided by a spring acting between said fixed end member and a head of the valve member, so that when the bellows expand said adjustment part and integral valve member are moved together away from the valve seat to compress the spring and open the opening in the valve seat to allow water to flow therethrough from the inlet to the outlet.

10. A system as claimed in any one of claims 6 to 9, wherein the adjustment part has means for varying the volume of the bellows, and thus the temperature at which the valve opens.

11. A system as claimed in any one of the preceding claims, wherein the valve incorporates a secondary feed facility.

12. A system as claimed in claim 11, wherein the secondary feed facility incorporates restricted flow channels through the valve seat and the valve member.

13. A system as claimed in any one of claims 1 to 3, wherein the valve incorporates an adaptor converting the valve to the normally open valve from a normally closed one.

14. A fluid flow control valve comprising an inlet and an outlet, a valve member and a co-operating seat, the valve seat defining an opening which is opened or closed by movement of the valve member, the opening, when open, communicating the inlet with the outlet, the valve member normally being held on its seat by means of a biasing force, there being provided a sensing unit having a temperature sensing part outside of the valve and a further part at the valve, so that dependent upon the temperature sensed by the sensing part, in use, the valve member moves off its seat to allow fluid to flow, in use, through said opening, from the inlet to the outlet.

15. A valve as claimed in claim 14, wherein said sensing part contains a fluid which expands and contracts as the temperature sensed, in use, by said sensing part changes.

16. A valve as claimed in claim 15, wherein the sensing part is connected to the valve by a capillary tube, expansion or contraction of the fluid in the sensing part and the capillary tube being arranged to produce, in use, a variation in force acting between respective fixed and movable parts of the valve.

17. A valve as claimed in claim 16, wherein said force is provided by a bellows acting between said fixed and movable parts of the valve.

18. A valve as claimed in claim 17, wherein said force of the bellows is opposed by said biasing force, said force overcoming said biasing force and moving said valve member off its valve seat, in use, when said temperature sensing part of the sensing unit senses a temperature equal to or greater than a predetermined temperature.

19. A valve as claimed in claim 18, wherein the fixed part of the valve is a body part defining the inlet, the outlet and the valve seat, and the movable part is an adjustment part containing said bellows.

20. A valve as claimed in claim 19, wherein one of said fixed and movable parts carries a pin which extends through opposed slots in respective opposite sides of the other of said fixed and movable parts.

21. A valve as claimed in claim 20, wherein the pin is carried by the movable part and extends through a stem of the valve member, the slots are in the fixed part and the biasing force is provided by a spring acting between a head of the valve member and said fixed part, so that on expansion of the bellows, in use, the adjustment part and the valve member are moved together away from the valve seat to compress the spring and open the valve seat opening to allow water to flow therethrough.

22. A valve as claimed in claim 20, wherein the pin is carried by the fixed part and extends through an end member to secure it to the fixed part, the slots are in the movable adjustment part, with which the valve member is integral, and the biasing force is provided by a spring acting between said fixed end member and a head of the valve member, so that on expansion of the bellows, in use, the adjustment part and integral valve members are moved away from the valve seat to compress the spring and open the valve seat opening to allow water to flow therethrough.

23. A valve as claimed in any one of claims 19 to 22, wherein the adjustment part has means for varying the volume of the bellows, and thus the temperature at which the valve opens.

24. A valve as claimed in any one of claims 14 to 23, wherein the valve incorporates a secondary feed facility.

25. A valve as claimed in claim 24, wherein the secondary feed facility incorporates restricted flow channels through the valve seat and the valve member.

26. A valve as claimed in any one of claims 14 to 16, wherein the valve incorporates an adaptor converting the valve to a normally closed valve from a normally open one.

27. A flushing system for a urinal substantially as hereinbefore described with reference to and as shown in the accompanying drawings.

28. A fluid flow control valve substantially as hereinbefore described with reference to and as shown in the accompanying drawings.