GB1167726A - Fuel flow control apparatus for gas turbine engines - Google Patents

Abstract

1,167,726. Gas turbine engine fuel systems. JOSEPH LUCAS (INDUSTRIES) Ltd. Feb. 20, 1967 [Dec.24, 1965], No.54855/65. Heading F1G. [Also in Division G3] Apparatus for controlling the supply of fuel to a gas turbine engine comprises a pump 5, an axially movable throttle 10 in a duct 11 between the pump and the engine, a piston 17 connected to the throttle and arranged in a cylinder 18 having one end supplied with fuel through a restricted passage 30 from the upstream side of the throttle, a manually operable plunger 23 movable coaxially within the piston to control the escape of fuel from said one end of the cylinder which is connected by a passage 32 with a further cylinder 33 containing a piston 34 with a restricted by-pass 37, and means 38 operable in response to movement of the plunger 23 for tending to cause flow through the by-pass so that rapid movement of the plunger 23 and means 38 causes a greater flow than the by-pass can accommodate to move the piston 34 and deliver fuel to the cylinder 18 whereby the piston 17 and hence the throttle will be moved at a greater rate than can be achieved by flow through the restricted passage 30. The plunger 23 has passages 22, 26 co-operating with an orifice 21 in a tubular extension 10a of the piston to form a moving seat followup. The pump 5 is adjusted by a servopiston 6 controlled by a valve closure on a lever 15b which responds to the pressure drop across the throttle acting on a diaphragm 15a and to changes in pressure within the compressor acting on a capsule assembly 15c. A device 16 responsive to temperature conditions within the engine modifies the pressure acting upon one side of the diaphragm 15a.