Improvements in or relating to water waste preventing cisterns for flushing the pan of sanitary closets

摘要

513,703. Water-waste-preventing cisterns. FARMER, B. F., [Representative of FARMER, C.S.]. April 14, 1938, No. 11454. [Class 26] A substantially air-tight flushing cistern having a manual ly-operated valve controlling the outlet is provided with buoyancy or pressure actuated means, or both, controlled by the waterlevel or gas pressure in the cistern and operatively connected to the outlet valve so as partly to balance the pressure on it and so facilitate its opening. In the cistern shown in Fig. 1 the outlet valve 16 is connected by a rod 17 to a float 20, and a second float 21 is carried by a lever 23 which passes through a slot in the rod 17 and carries a counterweight 27. The valve 16 is raised from its closed position, shown in broken lines, by a cam 30 operated through linkage from an external handle 34, the force tending to hold the valve closed due to the pressure in the cistern being largely counteracted by the float 20 and also the float 21 acting through the lever 23. After the valve has been initially lifted by the cam the discharge commences through ports 15 in the wall of the outlet pipe, and the lift is then completed by the float 20. As the water-level falls in the cistern the float 21 sinks and finally causes the valve 16 to close. If the initial pressure, before refilling of the, tank is atmospheric, the tank may be emptied completely at each flush, but if the pressure is above atmospheric (obtained by charging the tank with compressed air through a non-return valve 35) the tank is not fully discharged to prevent loss of pressure. In a modification the float 20 is replaced by a piston working in a vertical cylinder and subjected on its underface to the pressure in the cistern.