| 摘要 |
<p>A siphon assembly 10 for a flushing cistern, said assembly including an inverted generally U shaped duct 11 having an up leg 14 and a down leg 12 the up leg being provided with an enlarged chamber 18 having a lower end open to the interior of the cistern in use and the down leg forming an outlet from the cistern in use for delivery of flushing water; and a vertically displaceable piston incorporating a flexible diaphragm 24 acting as a one way valve, said piston being movable in said chamber to initiate a siphonic flushing action operatively discharging water through said duct from the cistern; a side wall 28 of the chamber defining a venting aperture 30 intermediate the top of the chamber and said lower open end, the assembly further including a first closure element secured in engagement with the venting aperture, the first closure element being shaped so as to define at least a first predetermined flush level lower than a top edge of the venting aperture when so secured.</p> |
