GB2325942A

GB2325942A - Siphon flushing mechanism for a W.C. cistern

Info

Publication number: GB2325942A
Application number: GB9711327A
Authority: GB
Inventors: David Roy Hathaway
Original assignee: Individual
Current assignee: Individual
Priority date: 1997-06-03
Filing date: 1997-06-03
Publication date: 1998-12-09
Anticipated expiration: 2017-06-03
Also published as: GB9711327D0; GB2325942B

Abstract

A siphon flushing mechanism for a WC cistern (1) comprises a siphon tube (2) locatable within the cistern so as to open at one end (5) within the cistern and to discharge at the other end to the pan, means (3) within the siphon tube for initiating siphoning of water to flush the pan, a siphon release tube (6) extending from a predetermined level on the siphon tube to a position on the cistern above the maximum water level therein, and control means (8) for selectively opening and closing the free end of the release tube to select partial or full flush, respectively. Also disclosed is a W.C. cistern with a ball-valve controlling flow of water thereto, means for conducting water from the outlet of the ball-valve to a discharge point above a hand-wash basin, and means for returning water from the basin to the cistern.

Description

WATER SAVING DEVICES Field of the Invention This invention relates to water saving devices for use with WC cisterns, and to a WC cistern incorporating such devices.

Background to the Invention As demand for water increases steadily throughout the world with increases in population and industrialisation, and as dimate changes, which may result from the greenhouse effect, reduce rainfall in some areas, there is an increasing need to reduce water consumption. One area where a substantial quantity of water is consumed is in flushing lavatories or water closets (WCs), and many proposals have been made for reducing the amount of water used in each flush without adversely affecting the efficiency of the flush. For example, the volume of water used in the flush can be reduced by inserting into the cistern a sealed water-filled bag or other object. This has the disadvantage that the reduction is fixed, so that while the volume of water may be sufficient to clear liquid waste from the WC pan, it may be insufficient to clear solids, resulting in the need to flush twice, thereby removing the water-saving advantage.

Dual-flush cisterns are known, in which holding down the flushing handle causes a full flush, while pressing and releasing the handle causes a short flush. These require care to achieve the desired result, and they are not readily applicable to all types of cistern, especially not to those having a vertical pull handle, as are favoured in some countries. Existing mechanisms cannot be converted to dual-flushing in this way.

Summary of the Invention According to one aspect of the invention, there is provided a siphon flushing mechanism for a WC cistern, comprising a siphon tube locatable within the cistern so as to open at one end within the cistern and to discharge at the other end to the pan, means within the siphon tube for initiating siphoning of water to flush the pan, a siphon release tube extending from a predetermined level on the siphon tube to a position on the cistern above the maximum water level therein, and control means for selectively opening and closing the free end of the release tube to select partial or full flush, respectively.

The control means preferabiy comprises a rotatable cap over the end of the release tube, the cap having a hole through the side thereof alignable with a hole in the wall of the tube, so that rotation of the cap closes or opens the hole in the tube wall.

The cap can be provided with markings to indicate full and partial flush positions.

The siphon release tube is suitably terminated, in use, in the spare mounting hole usually provided in the cistern to permit alternative left- and right-hand fitting of the flush lever. The tube may be a flexible tube to permit easy fitting to different designs of cistern.

Conveniently, the siphon mechanisms will be manufactured with an aperture for fitting of the release tube, preferably with a short stub pipe extending therefrom to permit ready push-fitting of the release tube. However, it will be possible to adapt existing mechanisms by cutting a hole in the mechanism at the desired level for the short flush, and then attaching the release pipe by means, for example, of a push-in stub fitting adapter.

In a typical flush mechanism, a flap valve is lifted to initiate the siphoning action.

The release pipe will be fitted to the mechanism at a location above the highest point of travel of the flap valve.

Another aspect of the invention provides a WC cistern with a ball-valve controlling flow of water thereto, means for conducting water from the outiet of the ball-valve to a discharge point above a hand-wash basin, and means for returning water from the basin to the cistern. In this way, the user of the WC can use the flush water for washing hands after flushing, the water then being re-used for the next flush. The automatic flow of water from the discharge point over the basin on flushing of the WC has the additional advantage of reminding the user to wash his or her hands after using the WC.

Existing WCs can readily be adapted to the system of this aspect of the invention, by fitting a pipe to the ball-valve mechanism to lead the water to a separate basin, and then providing a return from the basin to the cistern. If the user chooses not to use the wash water, it is not wasted, but flows to the cistern for use for flushing as normal.

Brief Description of the Drawings In the drawings, which illustrate exemplary embodiments of the invention: Figure 1 is a diagrammatic sectional elevation of a cistern according to one aspect of the invention; Figure 2 is an enlarged diagrammatic sectional view of the control valve for use with the cistern of Figure 1; and Figure 3 is a diagrammatic sectional elevation of a cistern and basin according to another aspect of the invention.

Detailed Description of the Illustrated Embodiments Referring to Figure 1, the cistern 1 contains a conventional siphon flush mechanism 2, comprising a flap valve 3 which can be lifted by rotation of a handle 4 mounted in the wall of the cistern to initiate the siphoning action which discharges the water from the cistern into the WC pan (not shown). In normal operation, the flushing continues until the level of the water in the cistern 1 drops below the opening 5 of the siphon tube, thereby breaking the siphon.

A tube 6 runs from an opening 7 in the body of the siphon tube above the upper limit of travel of the flap valve 3 to a control mechanism 8 mounted in the wall of the cistern 1 above the maximum water level in the cistern. As may be seen from Figure 2, the control mechanism consists of an inner pipe 9 having an opening 10 in the wall thereof, with a cap 11 mounted over the pipe 9 so as to be rotatable thereon. The cap 11 has an opening 12 in the side thereof which can be aligned with the opening 10 so as to permit air to enter the tube 6. Alternatively, the cap can be rotated so that the openings 10 and 12 do not align, and the tube 6 remains closed.

In use, if the tube 6 is open via the control mechanism 8 during flushing, the flush continues until the water level in the cistern 1 reaches the level of the opening 7 in the siphon tube. The tube 6 then admits air to the siphon tube, breaking the siphon and stopping the flush before all the water has been discharged from the cistern. With the tube 6 closed, the flush is not broken at that level, but continues as normal until the water level drops below the lowermost opening 5 of the siphon tube.

Referring now to Figure 3, the cistern 30 comprises a ball-valve 31 actuated by a ball float 32 whose position is determined by the water level. The balWvalve 31 is connected to a water supply pipe 33 in the conventional manner. It is usual for the balC valve to discharge water, when opened, directly into the cistern 30, typically through a downwardly directed tube. In this aspect of the present invention, the ball-valve 31 is connected to a pipe 34 which leads to an open discharge nozzle 35 above a washhand basin 36 located near to and above the cistern. A drain pipe 37 leads from the basin 36 back into the cistern 30.

In use, when the WC is flushed in the conventional manner, the ball float 32 drops as the water is discharged from the cistern 30 into the pan (not shown), opening the ball-valve 31 and allowing water to flow from the supply pipe 33 into the pipe 34 and from there be discharged into the basin 36, permitting the user to wash his or her hands. The water is collected in the basin and returned to the cistern 30 via the drain pipe 37. Although the water at this stage may contain a small amount of soap and/or dirt, this will have no adverse effect on the flushing of the WC.

It is also possible to provide a valve controlling flow from the discharge nozzle 35 into the basin, for example to permit the flow to be regulated to a slower rate, or to be delayed until required.

it will be appreciated that, while reference has been made to a ball-valve, other types of float valve may be used with this aspect of the invention.

Claims

1. A siphon flushing mechanism for a WC cistern, comprising a siphon tube locatable within the cistern so as to open at one end within the cistern and to discharge at the other end to the pan, means within the siphon tube for initiating siphoning of water to flush the pan, a siphon release tube extending from a predetermined level on the siphon tube to a position on the cistern above the maximum water level therein, and control means for selectively opening and closing the free end of the release tube to select partial or full flush, respectively.

2. A siphon flushing mechanism according to Claim 1, wherein the control means comprises a rotatable cap over the end of the release tube, the cap having a hole through the side thereof alignable with a hole in the wall of the tube, so that rotation of the cap closes or opens the hole in the tube wall.

3. A siphon flushing mechanism according to Claim 2, wherein the cap is provided with markings to indicate full and partial flush positions.

4. A siphon flushing mechanism according to Claim 1, 2 or 3, wherein the siphon release tube is a flexible tube.

5. A siphon flushing mechanism, substantially as described with reference to, or as shown in, Figures 1 and 2 of the drawings.

6. A WC cistern with a ball-valve controlling flow of water thereto, means for conducting water from the outlet of the ball-valve to a discharge point above a handwash basin, and means for returning water from the basin to the cistern.

7. A WC cistern, substantially as described with reference to, or as shown in, Figure 3 of the drawings.