GB2113267A - Variable-flush valve-discharge cistern - Google Patents

Abstract

The time for which the discharge valve (not shown) of a w.c cistern is open is controlled by a hydraulic dashpot 60 operated by the cistern handle 10. The degree of rotation of the handle 10 determines the time lag for recovery of the dashpot. The handle operates on a first shaft 11 which, through arm 13 and rod 16, operates the dashpot, rotation of the first shaft 11 causing through cam 18 and follower 26, rotation of a second parallel shaft 20 which opens the water valve by raising lever arm 40 and its valve-actuating rod 50. Recovery of the dashpot causes both shafts to return to their initial position, so closing the water valve. <IMAGE>

Description

SPECIFICATION A water control device for flush toilet This invention relates to means for selectively controlling the volume of water used in a flush toilet.

Large volumes of water are used in a conventional flush toilet, much of it unnecessarily when only urine is to be flushed away. This invention provides a means for selectively controlling, according to the particular requirement, the volume of water to be flushed through the toilet.

The control means, which is suitable for a toilet cistern in which a water release valve is opened by operation of a lever handle, comprises a hydraulic dashpot, the piston of which is displaced to a controlled degree on selective operation of the lever handle to open the valve, the piston being returned over a period controlled by flow of fluid in the dashpot to its starting position on reaching which the water release valve is closed.

The invention is described by way of example with reference to the accompanying drawings in which: Fig. 1 shows an exploded view of the control means of this invention.

Fig. 2 shows an enlarged part-sectional view of the hydraulic dashpot shown in Fig. 1.

Fig. 3 shows an outer view of the control box shown in Fig. 1.

Fig. 4 shows a general view of a toilet cistern fitted with the control means shown in Fig. 1.

As shown in Fig. 1 the control box (1) is a hollow rectangular body, on the outer surface of which is mounted a square base (2), carrying a shaft bearing (3) with external threads (4). A round pad (5) with a scale marked on the surface is fitted over the shaft bearing (3) and is secured thereon by a nut (6). The bearing (3) carries a shaft 11. The front end of a the shaft which projects out of the box is notched at (12) and a handle (10) which is fitted on the front end of the shaft (11) is secured in position by the notch. Adjacent the square base (2), is a through hole (7) in the box (1) for mounting the rebated end (21) at the front end of a second shaft (20).

The main shaft (11) carries a lever arm (13) having a small hole (14), the arm being coupled to a connecting rod (16) by a pin (15) which passes through the small hole (14) and a corresponding hole (1 7) at the upper end of rod (16). At the rear of the main shaft (11) is a round sliding cam (18) having a check rebate (19) at one end and a catch piece (8) at the opposite end. The rear end (9) of the main shaft is fitted into the round hole (31) on the box bottom (30).

At the front of the actuating shaft (20) the rebated end piece (21) fits into the through hole (7). From the right side of the shaft (20), extends a latch piece (26) having a recess (22) under its front tip and from the left side of the shaft (20), extends a lever (23). The rear end (25) which is provided with a round hole (24) fits through a round hole (32) in the box bottom (30).

A lever (40) is bent at a right angle at one end (41) and the angled portion is provided with a round hole (42). Near that end of the lever is a large round hole (43) and near the opposite end are two round holes (44, 45). The rear end (25) of the shaft (20) passes through the hole (43) and is secured to the lever by a screw (46) which fits through the holes (42) and (24).

The actuating rod (50) consists of two sections connected by a connecting sleeve (53). The upper end of the upper section is formed into a hook (51) for hooking into one of the round holes (44, 45) of the lever (40), and the lower end, which is lefthandedly threaded, is screwed into the top of the connecting sleeve (53). The upper end of the lower section of the rod (50) is righthandedly threaded and is screwed into the bottom of the sleeve (53), the lower end being formed into a hook for connection to the wate valve (81). The total length of the rod (50) may be adjusted by adjusting the length of said two sections screwed into the connecting sleeve (53).

The box bottom (30) is a rectangular thin plate in which two round holes (31,32) are provided and from which a small salient block (33) projects.

The hydraulic control assembly of this invention comprises a hollow hydraulic cylinder (60), containing a spring (61) and a piston (62) with oil seal (63).

On the top of the cylinder (60) is fitted a rubber lid (64). The connecting rod (16) passes through a round hole (65) in the rubber lid (64) and into a round hole (66) of the piston (62). The end of the rod is fixed to the piston by means of a pin (68) which passes through a small hole (67) in the piston (62), and into a small hole (29) in the end of the rod (16).

Fig. 2 shows an enlarged exploded view of the hydraulic control assembly. Inside the hydraulic cylinder (60), there is a ring flange (70) between the upper and lower parts of the bore. In the upper part the bore is wider and a small clearance is provided between the piston (62) and the inner wall of the cylinder (60). In the lower part of the cylinder (6) the bore is narrower and in it the piston is a close fit. A projection (71) on the top of the piston (62) has an oil outlet (72), an oil inlet (73) passes through the face of the piston (62), and in a central round passage (65), a steel ball (69) is fitted as a check valve.

Fig. 3 shows an external view of a control means of this invention. When it is completely assembled with all the components as shown in Fig. 1 and 2, it will be tightly sealed. In operation when fitted in a cistern the handle (10) is turned to rotate the main shaft (11); at the same time, the check rebate (19) of the cam (18) disengages from the latch recess (22) of the actuating shaft (20), and the cam (18) is rotated counterclockwise. By this means the latch piece (26) and the lever arm (40) are raised, the latter so opening the valve (81). Further, the connecting rod (16) attached to the lever arm (13) of the main shaft (11) will push the piston (62) in the hydraulic cylinder (60) downwards to compress the spring (61).As the piston descends, the hydraulic fluid in the hydraulic cylinder (60) will push the steel ball (69) upwards and will flow through the oil outlet (72) into the upper part of the hydraulic cylinder (60). On release of the handle, the compressed spring (61) will return the piston (62) upwards, and the hydraulic fluid will flow back through the oil inlet (73), into the portion under the piston (62). Simultaneously, the connecting rod (1 6) will drive the main shaft (11) and the cam (1 8) will rotate ciockwise until the top of the connecting rod (16) contacts the lever (23) of the actuating shaft (20) and then pushes the latch (26) into engagement of the recess (22) with the rebate (19).When the piston (62) is inside the upper part of the hydraulic cylinder (60) it will rise more rapidly, as a result of the clearance with the inner wall surface of the cylinder (60), than when it is in the lower part. Such rapidly raising force will cause the lever (40) to drop to actuate the actuating rod (50) so as to close the water valve (81).

The projection (33) on the bottom of the box serves to limit the rotation of the lever arm on engagement therewith of the catch piece (8).

Fig. 4 shows the embodiment of this invention installed in the cistern (80) of a flush toilet. The box (1) is installed inside the cistern (80) with the handle (10) fitted outside the cistern (80). The actuating rod (50) is connected to the water valve (81), which is a solid piece of rubber.

The embodiment described is designed to flush water in four different phases in accordance with the scale on the round pad (5). Each phase will lasi for about 2.5 seconds, and the maximum volume of hydraulic fluid that can be pumped above the piston (62) will flow back within about ten seconds. The divisions on the scale shown on the round pad (5) indicate 2.5 seconds from the first division. five seconds from the second division, 7.5 seconds from the third division, and ten seconds from the fourth division.When the user turns the handle (10) to the first division (2.5 seconds), the latch piece (26) of the actuating shaft (20) will rotate as a result of being driven by the cam (18) to move the lever (40) upwards and to pull the actuating rod (50) to open the water valve (81) for flushing; simultaneously, the piston will be pushed down in the dashpot and fluid will be displaced into the upper part of the cylinder. On release of the handle, the fluid displaced through the oil outlet (72) will flow back through the oil inlet (73) and the piston (62), impelled by the recoil force of the spring (61), will push the connecting rod (1 6) upwards to rotate the main shaft (11). This will actuate the actuating shaft (20) to cause the lever (40) to move downwards so as to lower the actuating rod (50) and close the water valve (81). The device can be operated over different phases; at the end of the time of each phase, the water valve will automatically be closed. For example, for flushing urine the user may rotate the handle to the first or second phase division of the scale; for flushing faeces the user may rotate the handle to the third and fourth phase division of the scale. Such controlled flushing will save water.

Claims (8)

1. A control means suitable for a toilet cistern in which a water release valve is opened by operation of a lever handle, which means comprises a hydraulic dashpot, the piston of which is displaced to a controlled degree on selective operation of the lever handle to open the valve, the piston being returned over a period controlled by flow of fluid in the dashpot to its starting position, on reaching which the water release valve is closed.

2. A control means as claimed in Claim 1 comprising a main shaft for operation by a lever handle, and a second shaft for operating the water release valve, the main shaft carrying a cam and a lever arm connected to the piston of the dashpot.

and the second shaft carrying a first arm which rides on the cam and by which the second shaft is rotated to open the water valve on rotation of the first shaft by the lever and a second arm which is contacted by the lever arm on the main shaft to return the second shaft and close the water valve on return of the main shaft by the dashpot.

3. A control means as claimed in Claim 1 or 2, in which the dashpot has a non-return valve through which fluid may flow on displacing the piston by rotating the main shaft and a restricted passage through which fluid may flow back on the return stroke of the piston.

4. A control means as claimed in any preceding claim in which in the first part of the dashpot cylinder traversed by the piston on operation of the lever handle the bore is wider than in the remaining part of the cylinder traversed by the piston.

5. A control means as claimed in any preceding claim in which the cam has a rebate at its lower end and the end of the first arm riding on the cam has a recess for engaging the rebate in which position of the arm the water valve is closed.

6. A control means as claimed in any preceding claim carrying a scale by means of which the degree of operation of the lever handle and thereby of the dashpot piston may be selected.

7. A control means as claimed in any preceding claim having a stop for limiting the degree of operation of the lever handle.

8. A control means as claimed in Claim 1 and substantially as described with reference to the accompanying drawings.