Improvements in or relating to fluid mixing valves for mixing two fluids at different temperatures

摘要

723,113. Fluid-pressure servomotor-control systems; fluid-actuated valves. TACCHI, P. G. Jan. 26, 1953 [Oct. 24, 1951], No. 24808/51. Class 135. A mixing valve for fluids at different temperatures has fluid proportioning valve means 45, 46 operated by a device 38 responsive to pressure variations in the mixture at the outlet 48 promoted by a device 56 responsive to the mixture temperature which varies the crosssection of an aperture 49 in the outlet. A temperature rise in the bimetal 56 exposed to the mixture through an orifice 55 moves a flap 51 to increase the throat area of a venturi 49 in the outlet whereby an increase in pressure in the pipe 58 open at 57 to the throat acts on one side of the diaphragm 38 to move it to the right and through a trunnioned lever 39, 43 pivoting on a diaphragm 40, moves the sleeves 45, 46 to the right to throttle the hot water or steam passing through the inlet 16 and ports 29 and increase the cold water flow through inlet 17 and ports 30. The opposite side of the diaphragm is open to atmosphere through a bleed so that with the outlet closed, fluid pressure moves the diaphragm fully to the right to completely close the sleeve 45 on a seating 63. Specification 690,570 is referred to.