AU662265B2 - A cistern - Google Patents

Description

662265 42928 AWT:PFB P/00/011 Regulation 3.2

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT

ORIGINAL

Name of Applicant: BRIAN EDSON JOYCE Actual Inventor: BRIAN EDSON JOYCE Address for Service: COLLISON CO.,117 King William Street, Adelaide, S.A. 5000 Invention Title: A CISTERN Details of Associated Provisional Applications: AUSTRALIAN Patent Application No. PL8191 Dated 8th April 1993 The following statement is a full description of this invention, including the best method of performing it known to me: j i D o AUTAINPtn ppiainN.P89 Dtd8hArl19 Th folwn sttmn safl ecipino hsivnin inldnfhtet ehdo efrin tkont e B« -I r .X ~LL' -L~TIU-I- 2 This invention relates to a cistern and more particularly a flushing cistern for a toilet.

The problem to which this invention is directed is to provide a cistern for flushing purposes which does not need to be pumped or have a high pressure head of water. The invention is particularly applicable to portable toilets but may be suitable for other applications such as caravan, mobile homes and the like.

BACKGROUND ART In portable toilets at present there is used a pumping system where the user pumps a handle or foot lever to pump enough water from a holding tank to flush the water. Another system uses direct flow from a tank to flush while holding a valve open.

This is inconvenient to do and may not provide the rush of water which provides suitable flushing of a toilet and could result in repeated or continuous operation thereby using excessive quantities of water.

,C Normally mains pressure water is not available for portable toilets and hence such portable toilets rely on a holding tank of water but the problem is to supply water from such a holding tank tothe flushing system of the toilet.

This invention proposes an improved flushing system or at least provides the public with a useful choice.

S DISCLOSURE OF THE INVENTION The invention is said to reside in a flushing cistern including a storage tank for storing water for flushing purposes and a flush tank to hold sufficient water for a single flush, the flush tank being within or below the storage tank and being in fluid communication with the storage tank to allow refilling of the flush tank from the storage tank after the single flush, the flush tank being a closed tank having a flushing fluid outlet, valve means to close the flushing fluid outlet, operating means to operate the valve means and an air vent pipe extending from the flush tank and opening to air above the maximum level of water in the m .Ii 3 4 storage tank.

It will be seen that by this invention there is provided a small flush tank which holds sufficient water for a single flush and which can be filled from the storage tank. A rush of flushing water may be released from the smaller tank by releasing the operating means to operate the valve means. The air vent which extends to open air above the maximum level of water in the storage tank will enable air to enter the smaller tank to replace water leaving the tank to prevent a vacuum forming and to allow flushing to strongly occur. The fluid communication between the storage tank and the flush tank is preferably of a 1 0 small size so that during the time that the valve means is open only a small amount of water will pass through the fluid communication into the flush tank and then pass out through the flushing outlet. When the valve means has shut, however, the fluid travelling through the fluid communication between the storage tank and the flush tank will refill the flush tank and fill up the air 1 5 vent to the level of water in the main tank.

The air vent pipe may include a valve at its lower end which closes under the flotation influence on the valve of water in the flush tank so that water does not .0 0 00 ~pass up the air vent pipe. The top end of the air vent pipe may terminate 000 0 4 inside or outside the storage tank.

99 4 9 There may be further provided a spring arrangement adapted to return the valve means to a closed position.

The configuration of the storage and flush tanks may be done in several ways.

In a first embodiment the flush tank may be within the storage tank with a o dividing wall between tht tanks having an aperture for the fluid communication between the tanks. The aperture may be low down in the o, dividing wall between the tanks so that most of the water in the larger tank can be used.

In an alternative embodiment the flush tank may be underneath the storage tank and have a dividing wall separating the storage tank and the flush tank which is part of a lower wall of the storage tank such that the fluid communication between the storage tank and the flush tank is by means of a caperture in the dividing wall.

IT7 It 4 Alternatively the flush tank may be separate from the storage tank with a hose joining the tanks to provide the fluid communication between the tanks.

There may be two fluslh tanks, a primary tank having a first volume and a secondary tank having a second volume and respective valve means in each of the two flush tanks so that a dual flush cistern is provided.

The first volume may be substantially greater than the second volume and one or the other valve means is actuated to give flushes of two different volumes.

Alternatively the first volume may be substantially equal to the second volume and one or both of the valve means may be actuated to give flushes of two different volumes.

In a two tank embodiment the primary tank and the secondary tank may be adjacent and there may be a dividing wall between the primary tank and the secondary tank in which the dividing wall does not extend completely to the top of the primary and secondary tanks and hence there may be a single 1 5 water inlet into the primary tank and the secondary tank from the storage tank and a single air vent pipe. Air may pass over the dividing wall between the two tanks to allow for the rush of flushing liquid. The dual tanks may be different sizes as discussed above or may be two small tanks of equal size with the valve on one tank operated to provide a small flush and both valves operated to provide a larger flush. A single operating lever may be provided for both ,alves which may be move in one manner of for a small flush and in a different manner for a larger flush.

Generally it will be seen that by this invention it has provided a flushing system which particularly because of the air breather pipe allows for immediate release of water from the smaller tank upon operation of the valve.

The operating means to operate the valve means may be provided with a lever arm arrangement so a push button arrangement can be used to operate the valve means or alternatively the valve means may be operated by means of a lifting method.

30 This then generally describes the invention but to assist to understanding the invention reference will now be made to the accompanying drawings which a a at al

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a st 'a$ If i Li-~ show preferred embodiments of the invention and methods of operating the invention.

In the drawings, FIG 1 shows a cistern according to one embodiment of this invention, FIG 2 shows the embodiment of cistern in FIG 1 after it has been operated, FIG 3 shows a slightly different embodiment of cistern according to this invention, FIG 4 shows an alternate embodiment with a separate tank, FIG 5 shows an embodiment with a smaller tank within the larger tank, and 1 0 FIG 6 shows a dual flush cistern according to this invention.

Looking more closely at the drawings and in particular FIG 1 and FIG 2 it will be seen that the cistern according to one embodiment of this invention tcomprises a large storage tank 1 for storing flushing water and a smaller flush tank 2 for storing enough water for a single flush. A filler tube 14 is prcvided to S 1 5 enable the tank to be filled with water. Fluid communication between the storage tank 1 and the smaller tank 2 is by means of a small aperture 3 in the dividing wall 4 between the larger tank and the smaller tank. An air vent 5 is provided extending from the smaller talk to open above the maximum level of water in the tank 1. It will be noted that in this embodiment that the air vent o- 20 pipe 5 terminates within the large tank 1. The smaller tank 2 is provided with a valve member 7 sitting on a valve seat 8 which closes off the flushing outlet 9.

An operating arm 10 is provided extending from the valve member 7 to above the tank 1 with a knob 11 for lifting the valve member 7 off the valve seat 8. A spring 12 is provided to return the valve member 7 to the valve seat when the knob 11 is released.

It will be seen that in FIG 1 the water in tank 1 has passed though aperture 2 into tank 2 and risen up the air vent 5 to the same level as in the tank 1.

As can be seen in FIG 2 the knob 11 has been raised which has lifted the 6 valve member 7 off the valve seat 8 and the water within the smaller tank 2 has flushed out as well as the water within the air vent 5. A small amount of water 13 is entering through the aperture 3 but in operation the valve member 7 is returned to its seat quickly and only a very small amount of water will have entered the tank 2.

FIG 3 shows an alternative embodiment of cistern according to this invention where the aperture providing fluid communication between the larger tank 1 and the smaller tank 2 is provided by the hole 15 through which the rod 16 for the valve operation passes. A lever arm arrangement is provided so that 1 0 button 17 can be pushed to operate the valve arrangement rather than being pulled as in the first embodiment.

Suitable means such as a spring 19 may be provided to prevent the button 17 from staying down or being held down thereby preventing water from the larger tank 1 flowing through the smaller tank 2 and out of the outlet 9 1 5 meaning wastage of water.

FIG 4 shows an alternative embodiment of cistern according to this invention.

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In this embodiment the small tank 20 is remote from the larger tank 21 with a hose or pipe 22 communicating between them to enable water flow for refilling o the smaller tank after flushing. The air vent pipe 23 still extends to above the 20 maximum level of water in the tank 21. The operating knob 24 has a shaft extending to valve member 26 with the shaft 25 passing along the length of the air vent tube 23 rather than passing through the wall 27 of the tank which would require sealing means.

FIG 5 shows a still further embodiment in which the smaller tank 30 is within 1.25 the larger tank 31.

In this embodiment a float valve 32 is supported in a cage 33 at the lower end of the air vent 34. When the water level in the lower tank 30 rises nearly to the upper wall 35 of the tank 30 then the float valve 32 rises in its cage and blocks l off the air vent 34 thereby preventing water from filling up the air vent tube 34.

Fluid r mmunication between the tank 31 and the tank 30 is provided by aperture 36 low down in the communicating wall between the larger and the t smaller tanks although the aperture 37 through which the operating rod 38

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7 passes could be sufficient aperture to allow refilling of the smaller tank Spring 39 is provided to return the valve member to its valve seat.

The embodiment shown in FIG 6 is adapted for a dual flush system. In this embodiment there is a single larger tank 40 which feeds to two smaller tanks 41 and 42 by means of a single aperture 43. A single air vent 44 allows air to enter ;he tank 42 and by passing through the gap over the wall 45 also enter the tank 41 depending upon whether valve member 46 opening from smaller tank 41 or valve member 47 opening from smaller tank 42 is opened. A single flushing outlet 48 is provided.

In this embodiment separate operating knobs 49 and 50 are provided but it will be realised that in alternative embodiments suitable mechanisms may be provided so that a single operating knob can be moved perhaps in one direction for a small flush and in another direction for a larger flush.

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Claims (12)

1. A flushing cistern including a storage tank for storing water for flushing purposes and a flush tank to hold sufficient water for a single flush, the flush tank being within or below the storage tank and being in fluid communication with the storage tank to allow refilling of the flush tank from the storage tank after the single flush, the flush tank being a closed tank having a flushing fluid outlet, valve means to close the flushing fluid outlet, operating means to operate the valve means and an air vent pipe extending from the flush tank and opening to air above the maximum level of water in the storage tank.

2. A flushing cistern as in Claim 1 wherein the air vent pipe includes a valve at its lower end which closes under the flotation influence on the valve of water in the flush tank so that water does not pass up the air vent pipe.

3. A flushing cistern as in Claim 1 further including a spring arrangement adapted to return the valve means to a closed position.

4. A flushing cistern as in Claim 1 wherein the flush tank is within the storage tank with a dividing wall between the tanks having an aperture for the fluid communication between the tanks.

A flushing cistern as in Claim T wherein the flush tank is underneath the storage tank and having a dividing wall separating the storage tank and the flush tank which is part of a lower wall of the storage tank such that the fluid communication between the storage tank and the flush tank is by means of a aperture in the dividing wall.

6. A flushing cistern as in Claim 1 wherein the flush tank is separate from the storage tank with a hose joining the tanks to provide the fluid i communication between the tanks.

7. A flushing cistern as in Claim 1 wherein there are two flush tanks, a primary flush tank having a first volume and a secondary flush tank having a second volume and respective valve means in each of the two flush tanks so that a dual flush cistern is provided. 0 ,1ffi 9

8. A flushing cistern as in Claim 7 wherein the first volume is substantially greater than the second volume and one or the other valve means is actuated to give flushes of two different volumes.

9. A flushing cistern as in Claim 7 wherein the first volume is substantially equal to the second volume and one or both of the valve means are actuated to give flushes of two different volumes.

A flushing cistern as in any one of Claims 7, 8 or 9 wherein the primary flush tank and the secondary flush tank are adjacent and there is a dividing wall between the primary tank and the secondary tank and the 1 0 dividing wall does not extend comrpletely to the top of the primary and secondary flush tanks and there is single water inlet into the primary flush tank and the secondary flush tank from the storage tank and a single air vent pipe.

11. A flushing cictern as in Claim 1 wherein the operating means to operate the valve means is provided with a lever arm arrangement so a push 1 5 button arrangement can be used to operate the valve means.

12. A flushing cistern substantially as hereinbefore described with reference to and as illustrated by any one of Figures 1 to 6 of the drawings. *a St, Dated this 28th day of June 1995 i BRIAN EDSON JOYCE By his Patent Attorneys COLLISON CO. S44 a I I i I 1 1. l-~r i;;ir i i ABSTRACT A flushing cistern particularly useful for a portable toilet with a main tank for storing water for flushing purposes and a small tank to hold sufficient water for a single flush. The small tank is in fluid corr munication with the main tank to allow refilling of the small tank from the main tank after the single flush. The small tank is a closed tank having a flushing fluid outlet, a valve to close the flushing fluid outlet and operating means to operate the valve and an air vent pipe extending from the small tank and opening to air above the maximum level of water in the main tank. There may be two small! tanks to allow for 10 different volumes of flush. The small tank may be integral with, adjacent to or separate from [he main tank. 4# 4 Ii i