GB701747A - Liquid fuel control means for prime movers - Google Patents

Abstract

701,747. Gas turbine plant. LUCAS (INDUS. TRIES), Ltd., J. Feb. 7, 1952 [Feb. 8, 1951] No. 3073/51. Class 110 (3). [Also in Group XXIX] In servo-operated liquid fuel control means for a jet-propulsion or gas turbine engine responsive to the pressure of the liquid fuel and to absolute blower or atmospheric air pressure, an ejector is provided to modify the action of the part responsive to blown or atmospheric pressure and a thermostatically or otherwise automatically operable valve controls the ejector. In Fig. 1 the delivery of the fuel pump, or a fuel throttle valve or by-pass valve is controlled by a spring- loaded servo-piston b under the control of a leak-off valve f carried by a spring-loaded lever g. The lever g is loaded by a piston k subject to the fuel pump delivery pressure in a line i leading to the burners and is also loaded by an evacuated elastic capsule m in a chamber n. The chamber n is connected to an ejector o adjacent the nozzle S thereof. The ejector is supplied with high velocity operating fluid which may be air delivered by the blower or liquid from the pump or other source. The flow of fluid to the ejector and hence magnitude of the reduced pressure acting on the capsule m is controlled by a valve p actuated through a lever r by a thermally responsive member q responsive to the temperature of the combustion chamber, the exhaust gas passage or other part of the prime mover. The valve p may alternatively be operated automatically by some other controlling factor e.g. speed. Thus the lever r may be operated by a centrifugal governor when the engine speed exceeds a predetermined limit. In Fig. 2, the servo-piston b regulating the fuel supply is controlled by a leak-off valve f operated by a piston l subject to the drop in fuel pressure across a throttle w between a fuel inlet 4 and a fuel outlet 5. The throttle u is loaded by a spring v connected to a lever 6 and is operated by a servo-piston w the opposite sides of which are connected by a restricted orifice y. The servo-piston w is controlled by a leak-off valve 3 carried by the lever 6 to which is also connected a spring 7. The lever 6 is operated by an evacuated elastic capsule m in a chamber n connected to an ejector o supplied by the blower. When the valve p operated by the heat responsive member is closed, the full blower delivery pressure is applied to the capsule m.