GB2361483A

GB2361483A - Cistern overflow system

Info

Publication number: GB2361483A
Application number: GB0009757A
Authority: GB
Inventors: Philip Nash
Original assignee: Individual
Current assignee: Individual
Priority date: 2000-04-19
Filing date: 2000-04-19
Publication date: 2001-10-24
Also published as: GB0009757D0

Abstract

In an overflow system for a cistern of the type incorporating a syphon 20, or other discharge arrangement, discharging to an outlet such as a toilet pan, the overflow system itself is arranged to discharge directly or indirectly into said outlet. The discharge arrangement may be provided as a prefabricated unit with the overflow system being formed as part of the prefabricated unit. In a preferred embodiment, the overflow system includes a conduit, in the form of a tube of plastics film 50 providing an entrance opening within the cistern, the tube having a discharge end communicating with the syphon duct 32 and arranged to prevent flow of air through the tube to the syphon duct during a cistern flushing operation, and thus arranged to prevent the overflow conduit interfering with the syphon action.

Description

2361483 PATENTS ACT 1977 Agents' Reference: P 1423 1 GB-H/JCC/ac

DESCRIPTION OF INVENTION

Title: " Cistern Overflow System" THIS INVENTION relates to an overflow system for a water cistern, for example of the type utilised in toilets and water closets. In such cisterns, a float-operated valve or ball-cock is generally utilised to maintain a predetermined water level within the water cistern to ensure that the appropriate volume of water is available for flushing on demand. To avoid the risk of flooding the premises in the event that the ball-cock becomes faulty or the float (ball) is punctured, excess water entering the cistern can be discharged safely to waste. However, where installations are not located against an outside wall, or are located on floors in buildings above ground level, a significant length of pipework may be necessary to connect an overflow outlet on a cistern with a suitable discharge location. This adds significantly to material and labour costs for many installations.

It is an object of the present invention to provide an overflow system for such cisterns by means of which the above disadvantage may be avoided.

According to the invention there is provided an overflow system for a cistern of the type incorporating a syphon discharge arrangement, or other discharge arrangement, discharging to an outlet such as a toilet pan, and mi which the overflow system itself is arranged to discharge directly or indirectly into said outlet.

I 2 In a preferred embodiment of the invention, the syphon discharge arrangement or other discharge arrangement is provided as a prefabricated unit and the overflow system is formed as part of the prefabricated unit. Accordingly, the overflow system can, in effect, be provided at the manufacturing stage, incorporated in the syphon or other discharge arrangement, so that no plumbing work specifically associated with the overflow system will be necessary during installation in premises.

Embodiments of the invention are described below by way of example with reference to the accompanying drawings in which:- FIGURE I is a schematic perspective view, partially in phantom, of a flushing cistern incorporating an overflow system in accordance with the invention, FIGURE 2 is a view in vertical section of part of the arrangement of Figure 1, to a larger scale, FIGURE 3 is a corresponding view in vertical section of a variant arrangement, FIGURE 4 is a partial, perspective view of a variant of the arrangement of Figures I and 2 of or of the arrangement of Figure 3, and FIGURE 5 is a fragmentary side view showing a further variant.

Referring to the drawings, Figure I illustrates schematically a water cistern 10 having a water inlet connected within the cistern to a float-operated valve 12 operated by a float 14 in known manner. That is to say, the valve 12 and float 14, with its associated connecting arm etc., form a conventional ',ball-cock". The cistern has, in conventional manner, a discharge pipe 16 jeading, for 3 example, to a conventional toilet bowl, the discharge pipe 16 being connected, within the cistern, with a syphon arrangement indicated generally at 20, incorporating, in conventional fashion, a piston 22 operable by a rod 24 and operating lever 26, again conventional, to initiate discharge of the contents of the cistern through the discharge pipe 16 in known manner. The syphon arrangement 20 is, save in one respect, of conventional form and will therefore not be described further.

The respect in which the syphon arrangement 20 differs from a conventional syphon arrangement is that an elbow 30 is provided on the outlet or discharge limb 32 of the sypbon and which forms part of an overflow arrangement, shown to a larger scale in Figure 2. Thus, referring to Figure 2, the elbow 30, connecting with the outlet or discharge limb 32 of the syphon 20 extends upwardly, from the elbow 30 into a vertical pipe 34 which carries a float valve. In the arrangement illustrated, the float valve comprises a valve member 36, for example of rubber, cooperating with a valve seat 38 within the pipe 34 adjacent the lower end thereof, the valve member 36 being connected, via a spring 40, with a guide member 42 which is freely slidable within the pipe 34 and is configured to allow the passage of water along the pipe 34 past member 42. The guide member 42 has a screw-threaded vertical bore receiving a complementary screw-threaded adjusting rod 44 which carries at its upper end a float 48. The arrangement is such that when the water level within the cistern is below the float 48, as it normally is, the valve member 36 sealingly engages the valve seat 38 so that when the lever 26 is operated to raise the piston 22 to start the syphoning action which will discharge the contents of the cistern into the discharge pipe 16, the valve member 36 prevents air from passing along the pipe 34 into the downstream limb of the syphon to relieve the pressure reduction within the discharge limb 32 of the syphon which is necessary to maintain the syphoning action. However, if, due to a faulty ballcock, the water 4 level within the cistern rises past the float 48, or at least past the position, relative to the float, at which the float begins to rise, the float will lift the guide member 42 and, with it, after some decompression of spring 40, the valve member 36, to allow water to pass, from the open upper end of the pipe 34, down the interior of the pipe 34, past the guide member 42 and past the valve member 36 and valve seat 38 into the discharge limb 32 of the syphon and thence to trickle down the discharge pipe 16 and thus safely exit via the lavatory pan and the connected wastepipe.

It will be appreciated that many alternative arrangements are possible within the scope of the invention. Thus, for example, if the float 48 is configured to seal adequately against the upper end of the pipe 34, a separate valve member 36 and spring 40 may be unnecessary as the float 48 will then itself serve as a valve member. To this end, it may assist if the upper end of the pipe 34 is flared upwardly and outwardly as illustrated to form a tapered seat for the float/valve member 48.

Figure 3 shows an alternative arrangement in which, instead of a valve and float arrangement, the pipe 34 is merely a simple pipe which is open at its upper end and which at its lower end connects via an elbow with the discharge limb 32 of the syphon. Within the discharge limb 32, the lower end of pipe 34 connects with a flexible tube 50 extending within the discharge pipe 16, the lower end of the flexible tube 50 being sufficiently low not to interfere with the syphoning action of the syphon. The tube 50 is conveniently a thin-walled tube of flexible polyethylene film.

In order to allow the position of the pipe 34 to be adjusted, for example to prevent it obstructing movement of the ball cock float or float arm, the part of the syphon discharge limb connected to the pipe 34 may be formed as a section 32A of pipe connected with the remainder of the syphon limb 32 and with the upper end of the outlet l6b from the cistern, by respective unions 33, incorporating appropriate sealing arrangements, for example using rubber "0" rings, which will allow the section 32A, and hence the pipe 34, to be swung about the vertical axis of the limb 32 whilst maintaining an adequate seal between the section 32A and the syphon and discharge pipe.

In an alternative arrangement, illustrated in Figure 5, the pipe 34 or a part of it, preferably a part which is at least close to the junction of the discharge limb 32 of the syphon (although not necessarily extending right up to the discharge limb 32), is circumferentially corrugated as shown and the material of the pipe 34 or at least of the corrugated portion is sufficiently flexible to allow the corrugated part to bend sufficiently, without damaging the pipe 34 or causing it to collapse, for the major, upper, part of the pipe to be adjusted in position so as to ensure, in any particular cistern configuration, that it does not obstruct movement of the ball float or float arm. The arrangement of Figure 4 or that of Figure 5 may be used with a valved pipe 34 such as that described with respect to Figures I and 2 or with an arrangement such as that described with respect to Figure 3, using simply an internal flexible tube connected with the lower end of the pipe 34.

In the present specification "comprises" means "Includes or consists of' and 11comprising" means "including or consisting of'.

The features disclosed in the foregoing description, or the following claims, or the accompanying drawings, expressed in their specific forms or in terms of a means for performing the disclosed function, or a method or process for attaining the disclosed result, as appropriate, may, separately, or in any

6 combination of such features, be utilised for realising the invention in diverse forms thereof t

Claims

7 CLAIMS

1. An overflow system for a cistern of the type incorporating a syphon discharge arrangement or other discharge arrangement, discharging to an outlet such as a toilet pan, and in which the overflow system itself is arranged to discharge directly or indirectly into said outlet.

2. An overflow system according to claim I wherein the overflow system is incorporated in said syphon or other discharge arrangement.

3. An overflow system according to claim 2 incorporating a syphon discharge unit having a syphon duct therein, and wherein the overflow system includes a conduit providing an entrance opening within the cistern, the conduit having a discharge end communicating with the syphon duct and valve means arranged to prevent or restrict flow of air through said conduit to the syphon duct during a cistern flushing operation, and thus arranged to prevent the overflow conduit interfering with the syphon action.

4. An overflow system according to any preceding claim wherein the syphon discharge arrangement or other discharge arrangement is provided as a prefabricated unit and said overflow system is formed as part of said prefabricated unit.

5. An overflow system substantially as hereinbefore described with reference to and as shown in Figures I and 2 of the accompanying drawings.

6. An overflow system substantially as hereinbefore described with reference to and as shown in Figure 3 of the accompanying drawings.

0 8 7. An overflow system substantially as hereinbefore described with reference to and as shown in Figure 4 of the accompanying drawings.

8. An overflow system substantially as hereinbefore described with reference to and as shown in Figure 5 of the accompanying drawings.