GB2125522A

GB2125522A - Fluid control valves

Info

Publication number: GB2125522A
Application number: GB08322268A
Authority: GB
Inventors: John David Archer
Original assignee: Individual
Current assignee: Individual
Priority date: 1982-08-18
Filing date: 1983-08-18
Publication date: 1984-03-07
Also published as: GB8322268D0

Abstract

A body 10 forming part of a tap includes a movable seal or washer 12 mounted on the end of a rod 14 and arranged to press against a seating 16 when closing off water flow to an outlet spout 18 of the tap. A second seal or washer 20 is supported by a threaded bolt 22 mounted in the body 10 and extending to a knurled nut 24. A cap 26 provided with a seal 28 fits around the bolt 22. To replace the washer 12 the second seal 20 is moved to close off the inlet supply and thus a remote mains stopcock need not be turned off.

Description

SPECIFICATION Fluid control valves BACKGROUND TO THE INVENTION The invention relates to fluid control valves.

The invention relates more particularly to fluid control valves which can be turned on and off and include seals and seatings for the seals. Difficulties arise because in order to service the valve and especially to change the seal the pressure has to be relieved in the supply line in the valve. To relieve the pressure may require closing a valve some distance away and at the same time closing off the flow to a number of other supply valves.

It is an object of the invention to at least reduce this problem.

SUMMARY OF THE INVENTION According to the invention there is provided a fluid control valve including a body and a movable seal arranged to press against a seating to close off fluid flow, and a second control valve mounted in the body upstream of first control valve arranged to close off the flow to the first control valve.

The seating may be arranged to have two opposed seating surfaces arranged to receive the movable seal on one surface and to cooperate with second control valve on the opposed surface. Preferably, the second control valve includes a seal arranged to bear against an inner surface of the body when not closing off the flow to the first control valve.

The second control valve may be arranged with means for securing the second control valve in an operative or non-operative position to prevent unauthorised operation of the second control valve.

The invention has particular application to manually operable domestic water taps to enable the seal of the first control valve to be replaced or the tap to be otherwise serviced.

Embodiments of the invention may however comprise other kinds of valves such as valves for use in gas supply lines, as well as liquid supply lines, and including industrial type valves.

BRIEF DESCRIPTION OF THE DRAWING Water taps according to the invention will now be described by way of example with reference to the accompanying drawing in which: Figure 1 shows a cross-sectional view of part of a bibcock tap; and Figure 2 shows a cross-sectional view of part of another pillarcock tap.

DESCRIPTION OF PREFERRED EMBODI MENTS Referring to the drawing, in Fig. 1 a body 10 forming part of a tap includes a movable seal or washer 1 2 mounted on the end of a rod 14 and arranged to press against a seating 1 6 when closing off water flow to an outlet spout 1 8 of the tap. A second seal or washer 20 is supported by a threaded bolt 22 mounted in the body 10 and extending to a knurled nut 24. A cap 26 provided with a seal 28 fits around the bolt 22.

In use, when it is required to service the tap and especially to renew the seal 12 the seal 20 is raised by screwing up the bolt 22 until the seal presses against the underside of the seating 16. This closes off the flow of water and the seal 1 2 can be raised and removed from the body 10 for servicing or replacement. While the seal 1 2 is removed the seating 1 2 can be cleaned and re-ground as required.

The facility of being able to close off the water supply at the tap during servicing means that the water supply system is not unnecessarily disrupted. Without the provision of the second seal 20 it is usually necessary to locate and turn off a mains valve and in many cases to drain a domestic water supply system in a dwelling house before a single faulty tap in that system can be serviced.

In Fig. 2, an alternative arrangement is shown which is generally similar to the tap described above except that the second seal 20A is spherical instead of planar.

It will be noted that the seal 20A fits snugly against the inside surface of the body 10 in the position shown in Fig. 2 so that the water pressure is not applied to the seal 28 during normal use of the tap.

In both embodiments the nut 24 may be replaced by a key slot or the like. The position of the seals 20 and 20A can also be rendered secure by locks or like means if required. This permits the closing off of the water supply to be carried out by key holders or authorised personnel only. The taps can therefore be rendered inoperative to supervise and limit the use of the taps as well as providing the facility of readily changing the seals 1 2.

It will be appreciated that the bolt 22 may be arranged having lost motion to allow the seals 20 and 20A to seat under the pressure of the water supply if desired.

Embodiments of the invention may be provided with external stamping providing a code or dimension of the size of the seal or washer 1 2. This means that before the tap is taken out of service a suitable replacement seal 1 2 can be obtained and made available. If the size of the seal 1 2 is not known prior to removal of the old seal 1 2 considerable inconvenience may result while a replacement seal is sought and brought to the tap, including a delay for several days if such a sized washer is not locally available.

The head portion (not shown) of the tap is normally attached to the body 10 by a screwed connection. Embodiments of the invention includes taps or valves in which the head portion is connected by a quick release connection such as for example a bayonet type connection. Such arrangements are particularly advantageous in industrial valve embodiments and where packing seals are provided in the head portion.

Claims

1. A fluid control valve including a body and a movable seal arranged to press against a seating to close off fluid flow, and a second control valve mounted in the body upstream of first control valve arranged to close off the flow to the first control valve.

2. A fluid control valve according to claim 1 in which the seating has two opposed surfaces arranged to receive the movable seal on one surface and to co-operate with second control valve on the opposed surface.

3. A fluid control valve according to claim 1 or 2 in which the second control valve includes a seal arranged to bear against an inner surface of the body when not closing off the flow to the first control valve.

4. A fluid control valve according to any one of claims 1 to 3 in which the second control valve may be arranged with means for securing the second control valve in an operative or non-operative position to prevent unauthorised operation of the second control valve.

5. Water taps substantially as herein described with reference to Fig. 1 or Fig. 2 of the accompanying drawing.