GB1352917A - Thermostatically controlled mixer fitting for hot and cold water - Google Patents

Abstract

1352917 Valves HANSA METALLWERKE AG 7 July 1971 [16 July 1970 (2) 28 April 1971] 31953/71 Heading F2V [Also in Division G1] A thermostatic mixing valve has hot and cold inlets 2, 3 from which water flows via respective .manually-operated valves 8, 8 and passages 65, 67 to separate chambers 46, 47 of a pressure equalizer 31 having a spool 48 controlling flow of hot and cold water to passages 35, 37 respectivelyin response to movement of a diaphragm 62 sensing the pressures in passages 35, 37. The latter conduct the water to ports 36, 38 controlled by closure members 117, 116 movable by a temperature responsive capsule 129-131 sensing the temperature of water in a mixing chamber 124 from which water flows to outlet 14 via port 39 which receives screw 126 to prevent rotation of the closure member assembly. Reaction rod 131 of the temperature responsive capsule abuts plate 149 in a stem 136 movable axially for temperature adjustment by rotation of knob 34. Depression of button 158 in knob 34 moves pin 159 clear of range limiting pin 160, allowing additional rotation of the knob. An overtravel spring 148 biases plate 149, and a weaker return spring 145 biases the closure member assembly. Each manually-operated valve 8 includes a closure member 11 on a stem 10 threaded into fixed nut 15 and adjustable at 26. A filter is fitted at 23 and a non-return flap at 24. Each of the valves 8, the pressure equalizer 31 and the thermostat unit 30 is withdrawable from the front of the valve following removal of screws holding flanges 17, 59, 43. In modifications, the temperature responsive capsule may be replaced by a bellows unit, a stack of bimetal dish springs or, as shown in Fig. 8, by a sensor 201 having an adjustable reaction rod 131 abutting a diaphragm 202 defining a wax-filled chamber communicating with feeler tubes 218. The diaphragm is carried by closure member 204 which moves to control flow of hot and cold water at 211, 213 to mixing chamber 220. The feeler tubes may alternatively be parallel with each other and be surrounded by return spring 209.