GB315976A - Improvements in pressure regulators - Google Patents

Abstract

315,976. Lewers, W. H., (Leslie Co.). June 25, 1928. Valves controlled by pilot or relay valves. - A pump regulator of the kind in which a pistonactuated main valve controlling the supply to a turbine driving a a pump is controlled by a diaphragm-actuated valve subject to pump - cutlet pres. sure, has the auxiliary valve further controlled by a pair of oppositely-acting diaphragms, subject to the pressure on the outlet side of the main valve, one diaphragm chamber being supplied d directly while the other is fed through a retarding device. In the form shown in the Figure, the main valve 10 has a guide stem 15 engaging a socket 18 in a removable cap 19 and is actuated by a leaky piston arranged on the outlet side of the main valve. Inlet pressure is admitted through conduits 23, 27 and auxiliary valve 26 to open the main valve. The auxiliary valve spindle is held by a spring 28 against a diaphragm 31 subject on its under side to outlet pressure through a passage 32. A frame 40, 41, 42 adjustably loaded by a spring 48 carries heads 37, 44, 46 of which 44 bears on the upper side of the diaphragm 31 while 37 and 46 bear on opposite sides of diaphragms 36, 33. The upper side of the diaphragm 33 which has an area equal to that of diaphragm 31 is subject to outlet pressure admitted through passages 30 and 53, pipe 50 controlled by a needle valve 51 and, if desired, through an auxiliary chamber 63. The upper side of the diaphragm 36 is subject to the pressure in the pump-outlet admitted through a passage 52. In a modification, a fourth diaphragm is added subject to boiler pressure so that the device maintains a constant difference between boiler and pump outlet pressures.