GB749783A - Liquid fuel regulating means for prime movers - Google Patents

Abstract

749,783. Gas turbine plant. LUCAS .(INDUSTRIES). Ltd., J. Aug. 12, 1954 [Aug. 14, 1953], No. 22440/53. Class 110(3) [Also in Group XXIX] The liquid fuel regulating means for jet propulsion engines and gas turbines described in Specification 677,138 is modified by replacing the restricted orifice in the main fuel conduit by a variable throttle c actuated by a fluid operated servo mechanism in dependence on the blower inlet pressure and by replacing the third restricted orifice referred to in claim 1 of Specification 677,138 by a manually or automatically actuated throttle z the pressure difference across which is utilized to control a liquid-operated servo-mechanism adapted to operate means for varying the rate of supply of fuel to the burner. The throttle c controls the passage of fuel through a throat b from a supply pipe g to a discharge pipe h leading to the burners. The throttle is actuated by a servo piston e controlled by a leak-off valve k carried by a lever m which is loaded by a spring d connected to the throttle and passes through a seal n into a chamber o containing an elastic evacuated capsule p responsive to blower inlet pressure. The inflow and outflow sides of the throttle c are connected by passages u, w to the opposite sides of a diaphragm t. The diaphragm t carries a valve y controlling the inlet to a passage x leading to a discharge flow exit and controlled by a manually operated throttle z. A flexible diaphragm 7 subject to the pressures on opposite sides of the throttle z operates a spring-loaded lever 8 carrying a leak-off valve 12. The valve 12 controls a ,spring-loaded servopiston 19 supplied with motive fluid through an inlet 15. The piston 19 operates fuel control means through a rod 21. In a modication, the leak-off valves k, 12 are replaced by baffles adapted to interrupt the flow of fluid across a gap in the supply passage to the servo-cylinder. In a further modification the fixed restriction v in the passage u is replaced by an adjustable throttle which may be operated manually or automatically. Thus it may be operated by an electromagnet the current in which is variable in response to temperature or some other variable factor associated with the fuel control system. The throttle z may also be operated automatically by the same means.