GB701096A - Improvements relating to liquid fuel regulating means for prime movers - Google Patents

Abstract

701,096. Gas turbine plant. LUCAS, Ltd., J. April 18, 1951 [March 7, 1950], No. 5696/50. Class 110 (3). [Also in Group XXIX] Means for regulating the supply of liquid fuel to a jet-propulsion engine, gas turbine or like prime mover comprises a hollow body part f divided into two compartments by a partition, such as the flexible diaphragm m (or a piston) which operates a liquid jet diverting or interrupting means in one of the compartments, the last-mentioned means being associated with a pair of motive liquid passages i leading to opposite ends of a servocylinder a and the outflow of partition actuating liquid from the other compartment being controlled by at least one normally open valve actuated by means responsive to a variable condition such as speed, blower air pressure &c. In Fig. 1 the spring-loaded servopiston b adjusts the obliquity of the swash-plate e of a fuel pump. Alternatively it may adjust a throttle or other fuel control means between the pump and the combustion chamber of the prime mover..The hollow body part f houses a pivoted jet pipe g supplied by a passage h from the pump delivery and actuated by a spring- loaded diaphragm m. The compartment containing the jet pipe is connected to a sump or the pump inlet by a restricted passage p and the other compartment is connected by another restricted passage o to the pump delivery. The latter compartment is also connected with a sump or with the pump inlet by a passage q under the control of one or more normally-open valves arranged in series so that when one or more of such valves are closed, the jet pipe g is moved to supply liquid to the left-hand side of the servo-piston and so reduce the fuel supply. Three such normally-open valves are shown. The first comprises a closure member s carried by a lever r actuated by a spring-loaded diaphragm 2. The chamber below the diaphragm 2 is supplied by a radial passage 6 in the rotating pump body 5 with fuel at a pressure related to the speed of the pump. The second normally-open valve comprises a closure member 12 on a spring- loaded lever 13 also loaded by a plunger 21 subject to pump delivery pressure, by an evacuated capsule 18 and by capsule 19 open to the atmosphere at 20. The third normally-open valve comprises a closure member 30 on a spring-loaded lever 29, actuated by pump delivery pressure acting on a plunger 32 and by the blower air pressure acting on a diaphragm 33 connected by a shackle 34 to an evacuated capsule 35. In a modification the ends of the passages are in alignment and liquid supplied directly to one side of the servo-piston from the pump delivery is diverted more or less in its passage' to the other side of the servo-piston by a pivoted shutter operating between the ends of the passages and connected to the diaphragm m.