GB1575398A - Twin-syphon water cister - Google Patents

Description

(54) TWIN-SYPHON WATER CISTERN (71) I, IAN Ross READ, a British Subject, of Rydons, Beech Drive, Kingswood, Surrey, do hereby declare the invention, for which I pray that a patent may be granted to me, and the method by which it is to be performed, to be particularly described in and by the following statement:- The invention relates to a lavatory cistern of the syphon type. In such a cistern water is allowed to rise to a certain level and flushing is achieved by operating a syphon unit to lift mechanically a quantity of water to start a syphon which drains the cistern to the lavatory bowl.

Experiments have shown that for a given quantity of water at a given head in the cistern the efficiency of the flush can be improved by improving the ducting which conducts the water from the cistern to the bowl. A useful improvement was achieved by ensuring a gradual bend instead of a sudden bend in the connecting pipe. Increasing the diameter of the pipe was not particularly effective. However, it has now been determined that further improvement can be effected by providing a plural duct outlet and preferably a plural syphon system. The present invention is based on this discovery.

According to one aspect of the invention there is provided a lavatory cistern of the syphon type comprising a cistern body for holding a predetermined amount of water above a lavatory bowl; a syphon arrangement in the cistern; a plurality of outlet ducts leading in parallel from the syphon arrangement out of the cisttrn body; and a mechanical linkage for operating the syphon arrangement.

The outlet ducts may be coupled to a single syphon unit. Preferably, however, there is more than one syphon unit, each with at least one outlet duct.

Thus, according to another and preferred aspect of the invention there is provided a lavatory cistern of the syphon type comprising a cistern body for holding a predetermined amount of water above a lavatory bowl; at least two syphon units in the cistern; a respective outlet duct from each syphon unit; and a common mechanical linkage for operating the syphon units in tandem.

The outlet ducts may be pipes coupled together beneath the cistern before entering the bowl. Preferably, however, the ducts enter the bowl at respective places.

The invention may be applied to any kind of lavatory, whether it be of the washdown, single or double syphonic trap, or helical trap type for example.

The invention will further be described with reference to the accompanying drawing the sole figure of which is a schematic perspective view of a lavatory embodying a cistern in accordance with the invention.

Referring to the drawing there is shown a lavatory having a pan 1 above which is mounted a cistern 2. The cistern body holds water to a level indicated by the broken line 3. The water inlet is shut off by a ball valve (not shown) in conventional manner. The cistern contains two syphon units 4 and 5. The syphon units are conventional and identical. Unit 4, for example has a bell 4a coupled to an up-pipe 4b. A down-pipe 4c is coupled to the uppipe by a U-bend 4d. Within the bell is a plate which normally rests at the bottom.

The plate is connected to a linkage 4e which is fixed to a rod 6. It will be seen that the linkages of both syphon units are coupled to rod 6.

To flush the cistern a lever 7 at the end of rod 6 is operated to turn the rod and thus raise the syphon plates. This lifts water over the U-bends and starts a syphonic action in each of the syphon units.

The down-pipes 4c and Sc are coupled to respective outlet ducts 8 and 9 which lead to different parts of an outlet channel 10 running around the rim of the pan. Flush water runs down the bowl from the outlet channel.

The flushing efficiency of the arrangement described with reference to the drawing may be used to reduce the required head of water in a cistern. Thus, a very low-level cistern may be provided, with advantages in space-saving and aesthetic appeal. Conventionally, for example, the overall height of a low-level lavatory and cistern is not less than 30". A system as described in the drawing can operate with an overall height of 24" or less.

The invention is not restricted to the arrangement described with reference to the drawing. For example, more than two syphon units may be employed to operate simultaneously.

WHAT I CLAIM IS: 1. A lavatory cistern of the syphon type comprising a cistern body for holding a predetermined amount of water above a lavatory bowl; a syphon arrangement in the cistern; a plurality of outlet ducts leading in parallel from the syphon arrangement out of the cistern body; and a mechanical linkage for operating the syphon arrangement.

2. A lavatory cistern of the syphon type comprising a cistern body for holding a predetermined amount of water above a lavatory bowl; at least two syphon units in the cistern; a respective outlet duct from each syphon unit; and a common mechanical linkage for operating the syphon units in tandem.

3. A lavatory cistern as claimed in either of the preceding claims wherein the outlet ducts enter the bowl at respective places.

4. A lavatory cistern substantially as hereinbefore described with reference to the accompanying drawings.

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

Claims (4)

**WARNING** start of CLMS field may overlap end of DESC **. to different parts of an outlet channel 10 running around the rim of the pan. Flush water runs down the bowl from the outlet channel. The flushing efficiency of the arrangement described with reference to the drawing may be used to reduce the required head of water in a cistern. Thus, a very low-level cistern may be provided, with advantages in space-saving and aesthetic appeal. Conventionally, for example, the overall height of a low-level lavatory and cistern is not less than 30". A system as described in the drawing can operate with an overall height of 24" or less. The invention is not restricted to the arrangement described with reference to the drawing. For example, more than two syphon units may be employed to operate simultaneously. WHAT I CLAIM IS:

1. A lavatory cistern of the syphon type comprising a cistern body for holding a predetermined amount of water above a lavatory bowl; a syphon arrangement in the cistern; a plurality of outlet ducts leading in parallel from the syphon arrangement out of the cistern body; and a mechanical linkage for operating the syphon arrangement.

2. A lavatory cistern of the syphon type comprising a cistern body for holding a predetermined amount of water above a lavatory bowl; at least two syphon units in the cistern; a respective outlet duct from each syphon unit; and a common mechanical linkage for operating the syphon units in tandem.

3. A lavatory cistern as claimed in either of the preceding claims wherein the outlet ducts enter the bowl at respective places.

4. A lavatory cistern substantially as hereinbefore described with reference to the accompanying drawings.