GB817232A - Improvements relating to mixing valves - Google Patents

Abstract

817,232. Disc brakes. RANCO Inc. Feb. 22, 1957 [March 2, 1956], No. 6008/57. Class 103 (1). [Also in Group XXIX] A mixing valve comprising a thermal element T in the mixing chamber 14 for operating valves 40, 41 has the mixture temperature selected by manual adjustment of the thermal element through a movable member 84 biased to one adjusting position, e.g. by a coil spring 85, and a friction brake or clutch operative by pressure fluid flowing through the valve to hold the member in manually selected position against the bias and responsive to a decrease in the pressure to release the member for movement under the bias. Contraction of the thermal element allows hot water pressure at 12 to open the valve 40 and reduce the opening of the valve 41 by the cold water pressure through the lever 47 contacting the thermal element at 49 and interconnected with the valve 40 by a spring 52. The mixture in chamber 14 flows to the outlet via a diaphragm valve controlled by a solenoid-operated pilot valve, the outlet containing a restriction whereby the outlet pressure is applied in a chamber 88 behind a diaphragm 87. The element T is urged upwardly by a spring or pressure in the chamber 14 acting on the sealing diaphragm 64 to abut a screw 71 carried by a lever 68 biased in an anticlockwise direction by a spring 81 until a screw 72 abuts an adjustable cam stop 73 which determines the lowest mixture temperature. Higher mixture temperatures are selected by rotating the lever 68 clockwise by means of link 75 connected to an eccentric 77 rotated by the handle 84. The handle is maintained in position against the spring 85 by friction between a casing held clutch plate 100 positioned between clutch plate 98 and a flange 101 of the eccentric when outlet pressure moves diaphragm 87 to the right to shift piston 89 and ring 91 acting on plate 98 via spring 93. The clutch yields to manual operation of the handle. The hot mixture is led to a washing machine tub, which, when full, closes the solenoid controlled outlet valve so that the reduced pressure releases the clutch and allows spring 85 to return the handle 84 to a low temperature rinse water setting.