GB2133054A - Dual-flush cisterns - Google Patents

Abstract

A cistern attachment providing a dual flush facility for the siphon- discharge unit (not shown) of a w.c. cistern comprises a normally-open push-button air valve 3 shown fitted in the spare flush-lever aperture of the cistern wall 2, the valve 3 having an air inlet tube 10 which depends to a predetermined partial-flush level in the cistern. The valve outlet 8 is connected by a flexible pipe to an air- admission fitting inserted in the siphon bell above the full water line. Actuation of the flush lever (not shown) produces a discharge which ceases as soon as the cistern water level falls to the lower end of tube 10 and so admits air to break the siphon. For a full discharge the button 7 must be held depressed to close the valve throughout the flush. <IMAGE>

Description

SPECIFICATION Dual flush device for toilet cisterns The invention relates to a push button air valve Figures 1 and 2 that, if not activated by hand causes the syphon action in a toilet cistern to flush half the contents of a full cistern only. But when the button is pushed in and kept in, whilst flushing, a full flush occurs. Thus single flush cisterns can be converted to dual flush if the cistern has a spare flush lever hole on the left or right side of its front above the full water line.

The valve is fitted from the inside of the cistern with a ring spacer 1 that allows for the thickness of the cistern's shell 2. If the shell is made of ceramic material such a spacer will not be required. With sufficient of the threaded part of the valve body 3 protruding outside, a nut 4 is screwed on so that the valve body is secured horizontally to the front of the cistern. Through the valve body the valve spindle is passed horizontally from the back until it is prevented from going further by an end stop 5 being part of the spindle against the end of the valve body.

Over the threaded end of the valve spindle outside the cistern a compression spring 6 is fitted and the push button 7 is then screwed onto the valve spindle. The spring is then at one end touching the push button and at the other end resting on a ledge inside the inner circumference of the valve body.

On the outer side of the valve body inside the cistern there are two tube spigots 8 and 9 fitted at the same distance from the end of the valve body but ninety degrees apart. This arrangement of the spigots allows the device to be fitted in a cistern either to the right or left which ever hole is vacant after the flush lever has been fitted. The horizontal spigot 8 is fitted with a flexible tube and the other end of the tube is attached to a breather outlet that has been fitted into the siphon bell so that the bell is pierced above the full water line of the cistern. Another tube is fitted to the vertical spigot 9 and of such a length 10 that when the cistern starts to empty, without pressing the button, and reaches the half flush level air enters the tube 10 and the siphon action is broken stopping the emptying action. The amount released depends on the length of the vertical tube 10.The cistern is then replenished by the water control valve and float in the cistern.

If a full flush is required the valve spindle is pushed in by the spring 6 loaded button 7 whilst the cistern empties. This action prevents the air from reaching the two spigots as a channel in the circumference of the valve spindle within the valve body 3 only allows air to flow when it is opposite the inside ends of both spigots. By pushing in the valve spindle the spigots are on the inside ends of both spigots closed and air does not get into the siphon bell until the full flush has been completed, when the siphon action is broken at the base of the bell. When the button is then released at the end of the full flush, the cistern will refill to its full level. If not pressed at the next flush, that flush will be halved.

Claims

1. In a full toilet cistern when siphonie action takes place with my invention fitted into the system it will always half flush, providing that the bottom of the vertical tube is at the half flush level within the cistern, thus saving water.

2. If the conditions mentioned in the above claim are changed and the spring loaded button is pressed in during the entire flushing action, a full flush will occur, when the water level will reach the bottom of the siphon bell.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (2)

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Dual flush device for toilet cisterns The invention relates to a push button air valve Figures 1 and 2 that, if not activated by hand causes the syphon action in a toilet cistern to flush half the contents of a full cistern only. But when the button is pushed in and kept in, whilst flushing, a full flush occurs. Thus single flush cisterns can be converted to dual flush if the cistern has a spare flush lever hole on the left or right side of its front above the full water line. The valve is fitted from the inside of the cistern with a ring spacer 1 that allows for the thickness of the cistern's shell 2. If the shell is made of ceramic material such a spacer will not be required. With sufficient of the threaded part of the valve body 3 protruding outside, a nut 4 is screwed on so that the valve body is secured horizontally to the front of the cistern. Through the valve body the valve spindle is passed horizontally from the back until it is prevented from going further by an end stop 5 being part of the spindle against the end of the valve body. Over the threaded end of the valve spindle outside the cistern a compression spring 6 is fitted and the push button 7 is then screwed onto the valve spindle. The spring is then at one end touching the push button and at the other end resting on a ledge inside the inner circumference of the valve body. On the outer side of the valve body inside the cistern there are two tube spigots 8 and 9 fitted at the same distance from the end of the valve body but ninety degrees apart. This arrangement of the spigots allows the device to be fitted in a cistern either to the right or left which ever hole is vacant after the flush lever has been fitted. The horizontal spigot 8 is fitted with a flexible tube and the other end of the tube is attached to a breather outlet that has been fitted into the siphon bell so that the bell is pierced above the full water line of the cistern. Another tube is fitted to the vertical spigot 9 and of such a length 10 that when the cistern starts to empty, without pressing the button, and reaches the half flush level air enters the tube 10 and the siphon action is broken stopping the emptying action. The amount released depends on the length of the vertical tube 10.The cistern is then replenished by the water control valve and float in the cistern. If a full flush is required the valve spindle is pushed in by the spring 6 loaded button 7 whilst the cistern empties. This action prevents the air from reaching the two spigots as a channel in the circumference of the valve spindle within the valve body 3 only allows air to flow when it is opposite the inside ends of both spigots. By pushing in the valve spindle the spigots are on the inside ends of both spigots closed and air does not get into the siphon bell until the full flush has been completed, when the siphon action is broken at the base of the bell. When the button is then released at the end of the full flush, the cistern will refill to its full level. If not pressed at the next flush, that flush will be halved. Claims

1. In a full toilet cistern when siphonie action takes place with my invention fitted into the system it will always half flush, providing that the bottom of the vertical tube is at the half flush level within the cistern, thus saving water.

2. If the conditions mentioned in the above claim are changed and the spring loaded button is pressed in during the entire flushing action, a full flush will occur, when the water level will reach the bottom of the siphon bell.