GB2179972A - Overflow fitting for a siphon-discharge w.c. cistern - Google Patents

Abstract

In a siphon-discharge flushing system comprising a U-shaped tube having an inlet arm (7) a discharge arm (8) and means for activating the siphon, an overflow fitting comprises a conduit (14) disposed parallel to and secured to the outer wall of the discharge arm. The lower end of the conduit (14) communicates with the interior of the discharge arm and the upper end (15) communicates with the interior of a tank forming part of the flushing system. <IMAGE>

Description

SPECIFICATION Improvements in or relating to flushing systems This invention relates to a new and improved syphon four a flushing systerrfi for a toilet bowl and an improved flushing system containing the same.

Conventional flushing systemsfortoilet bowls comprisegenerallyatankwhich is located in some convenient position above a toilet bowl, a syphon for discharging water into the bowl and meansfor activating the syphon. In order to ensure that the tank is always filled with water and ready for use the tank is generally connected to a source of supply e.g. a mains supply and water is allowedto discharge into thetank through some form of valve which prevents water entering the tank directly the surface ofthe water has reached some predetermined level usually indicated by a mark on the inner wall of the tank. One especially common form of valve incorporates a so-called ball cock which comprises a valve containing a piston the movement ofwhich controls the flow of water.The movement ofthe piston is itself controlled by an arm one end ofwhich is connected pivotally to thevalve whilstthe other end is attached to a ball which floats on the surface ofthe water in the tank. When the level ofthe waterfalls during the flushing operation the ball falls and the arm pivots downwards and in so doing the piston moves to a position so as to permitwaterto flow into the tank. When the flushing operation ceases a reverse cycle of operations takes place in that the ball rises in the tank until the level reaches the mark in the tank. Atthis stage the piston in the valve moves in reverse direction thus stopping the flow of water. On occasions valves do not function correctly.Thus parts may become worn due to prolonged use or particles of foreign matter may interfere with the correct working ofthe valve. In either case there is a tendency for water to enter into the tank inspite ofthe upward pressure of the ball acting through the lever to close the valve.

Accordingly in order to preventthe tankfrom overflowing it is customary to provide an overflow pipe which is usually connected to the tank at some position above the position reached by the level ofthe waterwhen the tank is in its normal filled condition.

The pipe is usually ledthroughtheexteriorwall ofthe building and is made to protrude from it from a short distance e.g abouttwelve inches. Conventional overflow pipes have certain disadvantages. Firstly the provision ofthe pipe requires a seperate plumbing operation which involves both time and expense.

Furthermore the discharge end ofthe pipe is often located on an exposed face of a building and during very cold weather if a valve is mal-functioning slightly the small discharge of waterfrom the outlet is liable to freeze and block the end of the pipes resulting in eventual fiooding in the room where tha tank is located. Even when an overflown pipe is wording satisfactorily the discharge of water down the side of buildings or on flower beds or pathswhich are often sited below the discharge end ofthe pipe is undesirable. I have discovered that a cheaper and more effective way of providing drainage for overflow is by use ofthe discharge arm of the syphon.

Accordingly this invention provides a syphon for a toilet flushing system comprising a U shaped tube having an inlet arm and a discharge arm, the discharge arm being longerthan the inlet arm, means for activating the syphon and a conduit co-operating with the discharge arm to enable the discharge arm to provide drainage means for overflow water.

Afurther embodiment ofthis invention comprises a flushing system for a toilet bowl comprising a tankfor containing waterforflushing the bowl automatic means for supplying water to the tank automatic means for arresting the flow of water into the tank when the level of water in the tank reaches a predetermined level and the syphon described above for discharging water into the bowl and for providing drainage for overflow water entering the tank in the eventoffailure ofthe arresting means to prevent the flow of water into the tank.

This invention is illustrated but not restricted by the fojlowing drawingsinwhich: Figure 1 shows a side view taken in vertical section of one form of syphon and a flushing system containingthe same.

Figure 2 shows a side view taken in vertical section of an-alternative form of syphon which can be used in the flushing system.

In Figure 1 atank(1) provided with a drop-on lid (2) is filled with water (3) from a valve (4) connected to a mains supply ofwater. The valve is operated by a lever (5) connected to a ball (not shown) which floats on the surface ofthe water. When thetank is filled to the extent required forflushing purposes the water level reaches an indicator line (6) marked on the wall ofthe tank. Atthis level the ball is in a raised position and the valve is closed.

Thesyphon consists of a U shaped tube having an intake arm (7) and a discharge arm (8) which is longer than the intake arm. The end ofthe intake arm (7) terminates in bell shaped cylinder (9) provided with a piston head (1-0) secured to the end ofa piston rod (11).

The latter is connected to the end of a lever (12) which rotates about a pivot (13) and the other end ofthe lever is provided with a handle (notshown).Apipe having an open end (15) is connected to discharge arm (8) at a position belowthatoftheopen end of intake arm (7).

The difference in height (16) is preferably not less than 2 inchesso asto ensurethatwhenthesyphon is activated theflow of water is sufficiently vigorous to flush the toilet bowl. Outlet (17) of discharge arm (8) connects with the inlet of the toilet bowl (not shown).

When the flushing system is ready for use tank (3) is filled wath water up to the operating level (6). The ball floating on the surface of the water is in a raised position thus causing pivot arm (5) to press upwards and to maintain valve (4) in a closed position thus preventing the entry of more water. In orderto flush the toilet the handle attached to lever (12) is turned causing lever (12) to move in an anticlockwise direction. As a consequence piston head (10) rises in bell (9) filling a sufficient proportion ofthe U tube (7 and 8) with water to establish the syphonic effect resulting in the emptying oftank (3) and the flushing of the toilet bowl.If priorto commencementto this sequence of operations valve (4) is leaking to the extent that water continues to enter the tank inspite of the force being exerted by lever (5) to maintain the valveclosedthelevelofwaterinthetankwill rise until water commences to overflow th rough opening (15) into overflow pipe (14). ltthen flows into discharge arm (8) ofthe Utube and finally reaches the toilet bowl.

In Figure 2 a syphon consists as in Figure 1 of a U shaped tu be having an intake arm (7) and a discharge arm (8). An overflow pipe (14) is located internally of the discharge arm. The pipe is provided with an inlet (15) and an outlet (17) which is located below the opening into the intake arm (7). Inthe vent offailure of the valve to function correctlythe level of water in the tankwill rise so asto coverthe U tube and finally to overflow down pipe (14) into the toilet bowl.

This invention has a numberofadvantages over existingflushing systems. Thus the U tube can be made of plastics materials incorporating the overflow pipe. The latter can be provided with an extensible end piece so that the level of the water in the tank can be varied. Alternatively the combined U tube and overflow pipe can be made with an overlong length of overflow pipe which can be cut to the desired length during installation of the flushing system. The present invention avoidesthe need of a separate plumbing operation and the disposal of overflow water with in the building avoids the danger of freezing causing blockage ofthe system.

Claims (9)

1. A siphon for a toiletflushing system comprising a U-shaped tube having an inlet arm and a discharge arm the discharge arm being longerthantheinletarm, means for activating the siphon and a conduit co-operating with the discharge arm to enable the discharge arm to provide drainage means for overflow water.

2. Asiphon according to Claim 1 whereinthe conduit comprises a pipe disposed parallel to and secured to the outer wall of the discharge arm the lower end ofthe pipe communicating with the interior ofthe discharge arm and the upper end ofthe pipe during use ofthe siphon communicating with the interior of a tankforming part of the flushing system.

3. A siphon according to Claim 1 wherein the conduit comprises a pipe disposed parallel to and located within the discharge arm the upper end of the pipe during use ofthe siphon communicating with the interior of a tank forming part oftheflushing system.

4. A siphon according to either of Claims 2 and 3 wherein apartofthewall of the discharge arm forms a part also ofthe wall ofthe pipe.

5. A flushing system comprising a tankfor con taining water automatic meansforsupplying waterto the tank, automatic means for arresting the flow of water into the tank when the water in thetank reaches a predetermined level andasiphon asclaimedinany one ofthe preceding claims two provide drainage for overflow water.

6. Any syphon as hereinbefore claimed in any one ofthe preceding claims.

7. Any siphon as hereinbefore described with particularreferencetothedrawings.

8. Any flushing system as hereinbefore claimed in Claim 5.

9. Any flushing system as herein before described with particular reference to the drawings.