GB2034392A

GB2034392A - Flow control device for a water distribution system

Info

Publication number: GB2034392A
Application number: GB7934860A
Authority: GB
Original assignee: Individual
Current assignee: Individual
Priority date: 1978-10-12
Filing date: 1979-10-08
Publication date: 1980-06-04
Also published as: GB2034392B

Abstract

For a water distribution system, which includes a supply pipe 10 connected to taps 12 and other water consuming devices 13, there is provided a device comprising a normally closed valve 14, that is connected in the supply pipe and is controlled by a timing means 17 so associated with the valve so that when the timing means is operated the valve will open for a predetermined time only, and a pressure sensing means 16 that senses the pressure downstream of the valve 14 and is arranged so that when the pressure downstream of the valve is less than the pressure upstream the timing means is operated. <IMAGE>

Description

SPECIFICATION Flow control device This invention relates to a device for insertion in a water supply pipe of a water distribution system.

The object of the invention is to provide a device whereby water can be supplied through the pipe only for a limited period of time unless the device is reset.

According to the invention a device for insertion in a water supply pipe of a water distribution system comprises a normally closed valve for connection in said pipe pressure sensing means responsive to the pressure downstream of said valve and arranged when there is a substantial change in said pressure as compared with a reference to supply a signal to a timing means which supplies a signal to open said valve for a predetermined time only.

Two examples of a device in accordance with the invention will now be described with reference to the accompanying diagrammatic drawings.

Referring to Fig. 1 of the drawings there is indicated at 10 a cold water supply pipe which incorporates the normal stop cock 11.

Connected to the pipe 10 are water consuming devices such for example as taps 1 2 and a cistern 13.

Connected in the pipe 10 downstream of the stop cock 11 is a valve 14 which is a normally closed valve which is opened by an electrical signal applied thereto through a supply cable 1 5. A sensing means 1 6 is connected to the downstream side of the valve 1 4 and this senses the pressure downstream of the valve against a reference value in this case set by the pressure upstream of the valve. The means 1 6 provides an electrical start signal which is conveyed to a timing means 1 7 by way of a cable 18, the cable 1 5 also being connected to the timing means.

The valve 14 is normally closed and with the taps 1 2 and the valve associated with the cistern 1 3 closed the pressure downstream and upstream of the valve will be substantially the same. If now one of the taps 1 2 is opened then the pressure downstream of the valve will fall and the fall in pressure will be detected by the means 1 6. A start signal is provided along the cable 1 8 to the timing means 1 7 and this provides a signal along the cable 1 5 to open the valve 1 4. When the valve is opened, flow of water can take place in the normal manner.If now the tap 1 2 is closed the flow of water will cease and the valve will close at the end of the period allowed by the timing means. If the tap is opened after the valve is closed then once again the means 1 6 provides a start signal to the timing means and water can flow. On the other hand if the tap 1 2 were left in the open position, the timing means would maintain the valve 14 in the open position for a predetermined time only. At the end of this time the valve 14 is closed and water will cease to flow through the tap 1 2. In the event that a continued flow of water through the tap is required then the timing means 1 7 must be manually reset.

The length of time the timing means will permit flow of water may for example in a domestic installation be of the order of fifteen minutes. This will be sufficient to allow for example the filling of a bath. It will be appreciated that this time can be reduced if this is thought desirable.

A further valve 1 9 is shown connected in parallel with the valve 1 4. The valve 1 9 is also connected to the timing means 1 7 and the valve 1 9 can be arranged to stay open for a further period of time after the valve 14 has closed. The permissable flow rate through the valve 1 9 is arranged to be less than that which will take place through the valve 14 and this reduced flow rate will permit for example the cistern 1 3 to complete the filling cycle before the valve 1 9 closes as the valve in the cistern is gradually closed.

The device acts to prevent continued flow of water in the event of some fault in the system for example the valve in the cistern sticking in the open position or in the event of a burst at some point in the system. It will be appreciated that often it is the case that taps drip. This dripping after the tap has been closed, will cause a reduction in the pressure downstream of the valve 14, and when the pressure downstream of the valve 14 falls to a sufficiently low value, the valve 1 4 will be opened for its normal timed cycle of operation, to restore the pressure downstream of the valve. Thus the taps 1 2 will continue to drip. Nevertheless, the system will guard against continuous flow of water in the event of a burst at some point in the system.

An air reservoir may be provided and connected downstream of the valve 14. This will tend to cut down on the number if valve cycles initiated when there is only a slight leakage from the system as caused for example by a dripping tap.

If it is known that use of water for an extended period of time is required, a manually operable valve may be placed in parallel with the valve 1 4 or a special switch can be provided on the timing means, which when operated, maintains the valve 14 open.

With reference now to Fig. 2 a shower mixer valve is indicated at 20 having an outlet connected to a shower head 21. A cold water supply pipe is indicated at 22 and a hot water supply pipe at 23. These two pipes incorporate electromagnetically operable normally closed valves 24, 25 respectively the operating windings of which are connected in parallel.

In parallel with the valve 24 is a restrictor 26 and connected to a point downstream of the valve 24 is a pressure sensing means in the form of a pressure responsive switch 27.

This senses the pressure downstream of the valve 24 and compares it with a reference for example the force exerted by a spring incorporated in the means.

In operation, with the valves 24, 25 closed and the mixer valve open a small flow of water will take place because of the restrictor 26. The flow of water will be cold water and will be considerably less than if the mixer valve were left in the open position without the provision of the valves 24, 25. When it is required to use the shower and the mixer valve 20 has been left open, the latter must first be closed. This allows the pressure downstream of the valve 24 to rise until at a predetermined value the means 27 operates to provide a signal to a timing device (not shown) which then opens the valves 24, 25 for a predetermined time allowing the shower once the mixing valve has been opened, to be used. If the mixer valve is closed either before or after the predetermined period and maintained closed then the valves will be maintained open but this does not matter since there will be no wastage of water.

Claims

1. A device for insertion in a water supply pipe of a water distribution system comprising a normally closed valve for connection in said pipe pressure sensing means responsive to the pressure downstream of said valve and arranged when there is a substantial change in said pressure as compared with a reference to supply a signal to a timing means which supplies a signal to open said valve for a predetermined time only.

2. A device according to claim 1 in which said reference is provided by the pressure upstream of the valve, and the sensing means provides a signal to the timing means when the pressure drop across the valve exceeds a predetermined value.

3. A device according to claim 2 including means for resetting the timing means to extend the time during which said valve is open.

4. A device according to claim 2 or claim 3 including a further normally closed valve connected in parallel with said valve said further valve have a smaller flow capacity than said first mentioned valve, said timing means being arranged to maintain said further valve open for a length of time longer than said predetermined time.

5. A device according to any one of the preceding claims including a manually operable valve connected in parallel with said normally closed valve or valves.

6. A device according to any one of the preceding claims including an air reservoir connected to a point downstream of said normally closed valve or valves.

7. A device as claimed in any one of the preceding claims in which said normally closed valve or valves is/are electromagnetically controlled.

8. A water distribution system incorporating a device as claimed in any one of the preceding claims and including taps and ball valves connected downstream of the normally closed valve or valves.

9. A device according to claim 1 in which said reference is provided by a spring and the sensing means provides a signal to the timing means to effect opening of the normally closed valve only when the pressure downstream of the valve is raised to a predetermined valve.

1 0. A device according to claim 9 including a restrictor in parallel with said normally closed valve, water passing through said restrictor to raise the pressure downstream of the normally closed valve when a system valve downstream of the normally closed valve, is closed, water being supplied through said system valve after it has been opened, for a predetermined time only.

11. A device according to claim 10 including a further normally closed valve connected in a further water supply pipe which is connected to said system valve said normally closed valves being operable together by said timing means.

1 2. A water distribution system incorporating a device as claimed in claim 9, said system valve comprising a mixer valve which receives cold water through said water supply pipe and hot water through a further supply pipe, said further supply pipe incorporating a further normally closed valve, said normally closed valves being operable together by said timing means.

1 3. A water distribution system comprising the combination and arrangement of parts substantially as hereinbefore described with reference to Fig. 1 of the accompanying drawings.

14. A water distribution system comprising the combination and arrangement of parts substantially as hereinbefore described with reference to Fig. 2 of the accompanying drawings.