GB901761A - Improvements in or relating to mixing valves for liquids - Google Patents

Abstract

901,761. Manually-actuated mixing valves. SHEARDOWN, J. M. Sept. 17, 1958 [June 17, 1957], No. 19028/57. Class 135. A manually-actuated valve for controlling the supply of cold water, a mixture of hot and cold water at a desired temperature, or hot water, comprises a valve plunger 8 formed with screwthreads 10 engageable with screw-threads 9 in a gland-nut 3 to move the plunger axially so that valving surfaces 16, 12 thereon are moved into and out of engagement with sealing-rings 14, 15 located in the bore 2 of a valve body 1, by collars 17, 18, to control flow between hot and cold inlets 4, 6, respectively, and a common outlet 7. In one extreme position of the valve plunger the valving surfaces 12, 16 engage the sealing-rings 14, 15, so that both the hot and cold water inlets are closed. On movement of the plunger outwardly, the surface 16 is first disengaged from the ring 15 to open communication between the cold water inlet 6 and the outlet 7. Further outward movement of the plunger then disengages the valving surface 12 from the ring 14 to allow the flow of hot water to take place and be mixed with the cold water, and, depending upon the position of the plunger the valving surface 12 co-operates with both rings 14, 15 to determine the temperature of the mixed water. In the other extreme position of the plunger, the valving surface 12 engages the ring 15 to close the cold water inlet with the hot water inlet fully open. The valving surfaces may be formed in the bore 2 or in a sleeve fitted therein whence the sealing-rings are carried by the plunger. A non-return valve may be fitted in the inlet for the liquid at the lower pressure, e.g. a ball valve 23 in the hotwater inlet 4. Instead of controlling the mixing of hot and cold water the valve may be used for mixing other liquids in desired variable proportions.