GB881907A - Improvements in or relating to flushing cisterns - Google Patents

Abstract

881,907. Siphon discharge flushing cisterns; joints for flushing cisterns. IDEAL BOILERS & RADIATORS Ltd. April 15. 1959 [April 25, 1958], No. 13250/58. Class 26. In a flushing cistern 1, Fig. 1, of the kind comprising a siphon 4 having a cylinder 7 in which is a plunger 11 operated (by a lever 16) to give siphonic discharge, having an air inlet 13 controlled by a sealing element 22 movable with the plunger 11, which can thus be operated to initiate a flow and either held in position to close the inlet 13 to give a full flush or released to open it so that the flushing action will cease when the level of the liquid falls to allow air to pass through inlet 13 in to the cylinder 7 to give a reduced flush, wherein the inlets cross-sectional area is not less than 0À25% and not more than 3% of the internal cross-sectional area of the cylinder 7. The plunger 11 is axially displaceable by the rod 12 extending through the inlet 13, sealed by the element 22 on the plunger 11, of material such as rubber, when the plunger is raised. The ratio for the inlet cross-sectional area is preferably not less than 0À25% and not more than 1À25% The wall 8 of the cylinder 7 has a raised part 9 defining a passage 10 as shown, Fig. 1, opening in to the cistern 1 with a hole 14 for the rod 12 to slide vertically. The wall 8 has pips 23 to engage the washer 22 when it seals the inlet 13, to form local compression therein so that, on release of the plunger 11, the washer 22 rebounds from the inlet 13. In a modification, Fig. 5, the inlet is replaced by an aperture 13a or apertures in the wall 8a, having a hole 40 for a rod 12a to raise the plunger 1 1a for siphonic action and there is a sealing diaphragm 46 of, e.g. rubber, on the plunger, or integral therewith. The rod 12a is guided by a lug 41 on the siphon 4 and a spring 45 between the lug 41 and a coupling member 42 (acted on by a lever 44) urges the rod 12a to its lowered position. The limb 5 of the siphon 4, Fig. 4, is secured adjustably in position by screws 24 and nuts 25, 26, and 30, a compressible resilient sealing ring 31 being between the limb 5 and the cistern bottom to give a fluid-tight connection. To form another such connection nuts 35 on the screws 24 act on a clamping dish 32 to tighten it when engaging a flange 34 (of an outlet pipe 33), to compress a sealing ring 36 between it and the cistern. Into the aperture 13a a tube with an outside diameter corresponding to the diameter of the aperture can be fitted to extend therefrom and thereby effectively to increase the height at which air enters the barrel 7 to break the siphon to modify the amount of the partial flush.