GB735845A - Improvements in or relating to fluid supply systems - Google Patents

Abstract

735,845. Valves. GENERAL MOTORS CORPORATION. Dec. 3,1953 [Dec. 19, 1952], No. 33577/53. Class 135. A valve arrangement for maintaining equality or proportionality of fluid flow in a number of conduits fed from a common source 46, and applicable to gas turbine fuel systems, comprises a spring-loaded piston 40 controlling a triangular flow restrictor port 32 in each conduit, a spring-loaded pressure drop control valve 82 in one conduit adapted to maintain a higher pressure than is liable to be developed in the conduits under ordinary operating conditions, and diaphragm actuated sleeve valves 60 in each of the other conduits, only one of which is shown. A passage 78, 76 leads from a point between the valve 82 and its associated restrictor port 32 to chambers 70 below the diaphragms whilst passages 72 connect the upper side of each diaphragm with a point between its associated valve 60 and restrictor port 32. Thus, each sleeve valve operates to maintain the same pressure drop across its associated restrictor port as occurs across that leading to the valve 82. The triangular restrictor ports may have equal apex angles for obtaining equal flows or unequal angles for unequal but proportional flows. The upper side of the piston 40 is vented by a passage 50 so that the piston moves upwardly to increase the opening of the ports 32 with increasing inlet pressures. Small quantities of fuel pass from the inlet 46 through a filter 100 and passages 102, 104 to the surfaces of the piston 40 and sleeve valves 60 to prevent the introduction of foreign matter. In a modification, pressure fluid from an independent source may act in the chambers 70, or alternatively, where one fuel nozzle has a higher resistance to flow than the others, its upstream pressure can be applied in the chambers 70 instead of the pressure before the valve 82.