GB1496329A - Valves for mixing hot and cold fluids - Google Patents

Abstract

1496329 Mixing valves MEYNELL VALVES Ltd 10 Jan 1975 [16 Jan 1974] 02137/74 Heading F2V A mixing valve comprises a hollow body 1 having inlets 4, 5 for hot and cold fluids and an outlet (not shown) for the mixed fluids, and, within the body 1, a first valve means 6-11 which controls the flow of the two fluids to a mixing chamber 14, a temperature responsive device 22 within the chamber 14 which regulates the operation of the first valve means to control the temperature of the mixed fluids, a volume control chamber 15 having an outlet 17 which is progressively covered or uncovered on rotation of a sleeve 19 through an external control knob 21 so as to vary the rate of flow to the outlet, and a second valve means 26-29 which operates between a first position in which mixed fluid flows from the chamber 14 to the chamber 15, and a second position in which the chambers are isolated from each other. The first valve means comprises a fixed sleeve 6 which has ports 8, 9 communicating wilh the hot fluid inlet 4 and the cold fluid inlet 5 respectively. A piston 10 formed with axial passageways 11 slides within the sleeve 6 and is urged towards the illustrated position by a spring 12. The temperature responsive device 22 is supported between the piston 10 and a piston 26 of the second valve means so that any increase in temperature within the chamber 14 causes the device 22 to expand and move the piston 10 down against the action of the spring 12 to close the ports 8. The temperature setting of the device 22 may be adjusted by means of a screw 31 which bears against the piston 26 within a hollow spindle 29. The second valve means is opened and closed by means of a control knob 30. In the closed position a sealing ring 27 mounted on the piston 26 seals the passageway between the chambers 14, 15 and the piston 10 is forced against the spring 12 into the position in which the ports 8 are closed.