GB2275697A - Variable-flush facility for syphon-discharge flushing cistern - Google Patents

Abstract

A siphon-discharge flushing cistern has adjustable 6 means 10 for regulating the volume of liquid discharged in the form of an air regulator for regulating admittance of ambient air. The regulator is in the wall of a bell 4 of the cistern and comprises an air inlet aperture comprising a substantially vertical elongate blind slot 12 which is obturatable at different heights by a manually slidable tubular device 11 which is reciprocable in a substantially arcuate guide way 13 forming part of the wall. In an alternative embodiment, the regulator is in a wall of a connector between the bell and the discharge leg of the siphon. <IMAGE>

Description

A SYPHON The invention relates to a syphon, particularly to such a syphon which is used in a cistern in a water delivering system.

Such syphons are often used for water closets (W.C.s) to deliver water for flushing lavatories.

It will be understood that syphons of the kind referred to herein usually comprise a syphon tube of inverted U-shape of which one limb provides an outlet tube whilst the other (shorter) limb provides an inlet tube formed, in its lower part, with a bell or housing, open at the bottom. In the bell there is a generally vertically reciprocatable piston or plunger adapted to be raised from a lower rest position to start a syphoning action which continues owing to a flexible diaphragm which is in essence a uni-directional valve incorporated in the piston or plunger.

Thus during use once flushing is commenced it usually continues until the water level in the cistern falls to a point at which air can enter the open bottom end of the bell, to terminate the syphonage action by creating the vacuum.

Such cisterns as described are usually only able to provide a fixed volume of water for flushing. However, this can be environmentally disadvantageous as it is often the case that too great a volume of water is flushed, which is wasteful.

There is a requirement therefore, for a cistern to be able to flush a varying amount of water. One way is to decrease the volume of water by immersing an object such as a brick in the water in the cistern. This is generally unpractical, and unaesthetic. Cisterns therefore being devised give a variable volume flush, but they provide absolutes, for example either a 7 litre flush, or a 9 litre flush, with no variation. Moreover, it is often the case that once the cistern has been converted via its syphon from a 7 to a 9 litre flush, or vice versa, it is not possible to reverse the flush volume back to 7 litres. It is an object of the invention to seek to obviate these disadvantages.

According to a first aspect of the invention, there is provided a syphon, for use in a cistern, comprising adjustable means for regulating the volume of liquid dischargeable by the syphon.

This means may comprise an air admittance regulator for regulating admittance of ambient air into the interior of the syphon. This provides for a relatively simple way to break a syphoning action.

The regulator may be in a wall of the cistern bell, or alternatively the regulator may be in a wall of a connector between the bell and the discharge leg of the syphon. Either construction is relatively simple and inexpensive.

The regulator may comprise means to adjust the level at which vacuum in the cistern is broken whereby to regulate the volume of liquid discharged.

The adjustment means may comprise an air admittance aperture means through an external wall of the bell, a manually slidable device for obturating the aperture means at varying levels, and passage means for communicating the aperture means with ambient air. This construction provides for relative simple adjustment.

There may be a guide way for the manually slidable device. This provides for a positive action.

The guide way may be of substantially channel shape in cross-section. This can readily by made, as by moulding.

The guide way may be of substantially arcuate shape in cross-section. This is an effective alternative construction.

The aperture means through the bell wall may comprise an elongate slot and the passage means may comprise a through slot in a wall of the guide way which is obturatable by the manually slidable device at varying levels whereby to pass ambient air through the guide way into the bell.

The aperture means through the bell wall may comprise an elongate slot and the manually guidable device may be tubular with its upper, in use, end being open to ambient air.

The adjustment means may comprise an air admittance aperture means through an external wall of the connector, and a manually slidable tubular device defining passage means for communicating the aperture means with ambient air.

The aperture means may be in a side wall of the connector.

The aperture means may be in an underneath, in use, wall of the connector.

The manually slidable device may comprise an external scale whereby to provide a visual indication of the regulated volume to be discharged.

The regulator may comprise an elbow shaped tube which is rotatable to adjust the height of an open mouth of the tube.

The regulator may comprise a tube which is secured to the connector, which tube may be adjustable in length as by being severable to a desired length.

According to a second aspect of the invention there is provided a cistern, including a syphon as hereinbefore defined.

Syphons embodying the invention are hereinafter described, by way of example, with reference to the accompanying drawings.

Fig. 1 is a side elevational view of one embodiment of syphon, for discharging a variable volume of water, according to the invention; Fig. 1A is a bottom plan view of the syphon of Fig. 1; Fig. 2 is a side elevational view of a second embodiment of syphon, for discharging a variable volume of water, according to the invention.

Fig. 2A is a bottom plan view of the syphon of Fig.2; Fig. 3 is a side elevational view of a third embodiment of syphon, for discharging a variable volume of water according to the invention; Fig. 3A is a bottom plan view of the syphon of Fig.3; Fig. 4 is a side elevational view of a fourth embodiment of syphon, for discharging a variable volume of water according to the invention; Fig 4A is a bottom plan view of the syphon of Fig.4; Fig. 5 is a side elevational view of a fifth embodiment of syphon, for discharging a variable volume of water according to the invention; Fig. 5A is a bottom plan view of the syphon of Fig.5; Fig. 6 is a side elevational view of a sixth embodiment of syphon, for discharging a variable volume of water according to the invention; and Fig. 6A is a bottom plan view of the syphon of Fig.6.

Referring to the drawings, in which like parts are indicated by like reference numerals, there are shown syphons 1, each for use in a cistern (not shown) such as that for a water closet, comprising adjustable means for regulating the volume of liquid (herein water) dischargeable by the syphon.

It will be understood that in all the embodiments the syphon 1 comprises a "down" leg 2 which is longer than the "up" leg 3, which up leg 3 terminates in a bell 4 which is open at the bottom 5 and has a reciprocable piston or valve, in use a vacuum being created in the bell by the valve, which vacuum is broken to discharge water past the valve up the up leg 3 through a horizontal, in use, connector 6 to the down leg 2, for say a lavatory or W.C. pan to which the cistern is connected either directly or by a pipe (not shown).

All the syphons 1 embodying the invention are capable of delivering or discharging a variable, regulated volume of water.

In Figs. 1 and 1A, there is shown a syphon which has an adjustable means 10 for regulating the volume of liquid discharged in the form of an air regulator for regulating admittance of ambient air into the interior of the syphon 1. The regulator is in the wall of the bell 4 and comprises an air inlet aperture in the form of an elongate substantially vertical in use blind slot 12 which is obturatable at different heights by a manually slidable tubular device 11 which is reciprocable in a substantially arcuate guide way 13 which forms part of the wall of the bell 4. The tube 11 has a cap 14 for ease of manipulation, and the guide way extends upwardly beyond the top (as viewed) of the bell 4, to provide a guide.

In use the slot 12, which is narrower than the diameter of the tubular device 11, is obturated by the body of the device 11 so that ambient air can only pass into the bell 4 to break the vacuum by passing down through the tube 11, out of the bottom thereof and through the exposed part of the aperture 12 into the bell 4 to break the vacuum. It will be understood that once the vacuum is broken atmospheric pressure acting on the water in the cistern forces water past the valve or diaphragm up the leg 3, across the connector 6 and down the lower leg 2 for flushing.Thus the volume of water discharged is variable depending on the position of the bottom of the tube 11, the higher it is the higher the volume of water discharged, because the volume of the vacuum created under the piston is greater so that a greater volume of water has to flow to fill the vacuum when it is broken by air passing through the tube 11 to below the valve as it rises, until it is just level with the bottom of the tube. The tube 11 thus forms a passage for communicating ambient air with the interior of the bell 4.

Figs. 2 and 2A show a second embodiment of syphon 1 similar to the first one, and which operates in a similar way. In this case, however, there is adjustable means 20 in which there is a manually slidable device 21 which is solid, and rectangular, and is a close sliding fit in a channel shaped guide way 22, the side 23 thereof remote from the bell 4 being open. Normally the device 21 closes the blind aperture 12 in the bell 4 and the open side 23 of the guide way 23 but as the device 21 is raised, it opens a passageway for ambient air through the open side 23 under the end of the device 21 and into the bell 4 through the blind aperture 12. The height of the device 21 therefore again regulates the volume by determining the height at which the vacuum is broken.

Figs. 3 and 3A show an embodiment in which there is an adjustable means 30 in the form of air admittance regulation in the form of a tube 31 which engages with a tight push fit on a hollow spigot 32 which depends from the underside of a bottom wall of the connector 6. The height of the bottom of the tube 31 determines the volume of water discharged because air is admitted to the bell 4 to break the vacuum when the water level falls to expose the end of the tube 31 to ambient air which thus breaks the vacuum in the bell and water is discharged, the higher the end of the tube 31 the greater the volume of water being discharged. The tube 31 may be adjustable in length, by for example being cut.

Figs. 4 and 4A show a fourth embodiment of syphon 1, similar to the third embodiment of Figs. 3 and 3A, but in this case there is a tube 41 in the form of two telescoping parts 42 and 43, so that it is adjustable in length by telescoping the tube part 43 with the tube part 42. The height of the bottom of the tube 41 as defined by the free end of the tube part 43 is thus variable, the interior of the tube 41 as in the third embodiment providing passage for ambient air to break the vacuum.

Figs. 5 and 5A show a fifth embodiment of syphon 1, similar to the fourth embodiment, in that the depending tube 50 is telescopic, comprising as before two parts 51 and 52. In this embodiment however, the hollow spigot 53 from which the tube 50 depends projects from a side wall of the connector 6, so the tube part 51 has a right angle end piece which is a tight push fit on the spigot 53.

Figs. 6 and 6A show an embodiment in which the volume of water discharged is variable by adjustable means in the form of a pivotable tube 60. By pivoting the tube 60 clockwise or anti-clockwise as shown by arrows 'A' and 'B', the height of the free end 61 of the tube 60 can be adjusted so that the vacuum in the bell 4 is broken at different heights of the valve and as the end 61 becomes exposed to ambient air as the water level on the cistern falls. The tube 60 is of L-shape or right angle configuration, one limb being much shorter than the other and mounted for pivoting on a hollow spigot 62 projecting from the side wall of the bell 4.

The devices 11, 21, 43 and 52 have a scale 7, graduated as shown, to provide a visual indication of the volume being discharged, at a particular extension of the device. This can easily be read using the end of the guide way or tube 13, for example, as a datum.

Claims (21)

1. A syphon, for use in a cistern, comprising adjustable means for regulating the volume of liquid dischargeable by the syphon.

2. A syphon according to Claim 1, the means comprising an air admittance regulator for regulating admittance of ambient air into the interior of the syphon.

3. A syphon according to Claim 2, the regulator being in a wall of the cistern bell.

4. A syphon according to Claim 2, the regulator being in a wall of a connector between the bell and the discharge leg of the syphon.

5. A syphon according to Claim 3 or Claim 4, the regulator comprising means to adjust the level at which vacuum in the cistern is broken whereby to regulate the volume of liquid discharged.

6. A syphon according to Claim 5, when dependent from Claim 3, the adjustment means comprising an air admittance aperture means through an external wall of the bell, a manually slidable device for obturating the aperture means at varying levels, and passage means for communicating the aperture means with ambient air.

7. A syphon according to Claim 6, comprising a guide way for the manually slidable device.

8. A syphon according to Claim 7, the guide way being of substantially channel shape in cross-section.

9. A syphon according to Claim 7, the guide way being of substantially arcuate shape in cross-section.

10. A syphon according to any of Claims 6 to 9, the aperture means through the bell wall comprising an elongate slot and the passage means comprising a through slot in a wall of the guide way which is obturatable by the manually slidable device at varying levels whereby to pass ambient air through the guide way into the bell.

11. A syphon according to any of Claims 6 to 9, the aperture means through the bell wall comprising an elongate slot and the manually guidable device being tubular with its upper, in use, end being open to ambient air.

12. A syphon according to Claim 5, when dependent from Claim 4, the adjustment means comprising an air admittance aperture means through an external wall of the connector, and a manually slidable tubular device defining a passage means for communicating the aperture means with ambient air.

13. A syphon according to Claim 12, the aperture means being in a side wall of the connector.

14. A syphon according to Claim 12, the aperture means being in an underneath, in use, wall of the connector.

15. A syphon according to any of Claims 6 to 14, the manually slidable device comprising an external scale whereby to provide a visual indication of the regulated volume to be discharged.

16. A syphon according to Claim 3, the regulator comprising an elbow shaped tube which is rotatable to adjust the height of an open mouth of the tube.

17. A syphon according to Claim 4, the regulator comprising a tube which is secured to the connector.

18. A syphon according to Claim 19, the tube being adjustable in length.

19. A syphon according to Claim 18, the tube being adjustable in length by being severable to a desired length.

20. A syphon, for use in a cistern substantially as hereinbefore described with reference to the accompanying drawings.

21. A cistern, including a syphon according to any preceding claim.