GB727201A - Improvements in fuel supply systems for gas turbine engines - Google Patents

Abstract

727,201. Gas turbine plant. GENERAL MOTORS CORPORATION. March 24, 1953 [April 4, 1952], No. 8015/53. Class 110 (3). A gas turbine fuel system comprising a primary fuel control valve connected in series with an overspeed governor valve has an underspeed governor valve, which maintains a pre-set low speed, connected between the inlet of the primary control valve and the outlet of the overspeed valve. The invention is described with reference to a gas turbine engine A driving a propeller C through reduction gearing B and a generator D, fly-ball governor 44 and fuel pump 17 through an auxiliary drive shaft 12. The fuel from the discharge of the pump 17 passes through a primary throttle control valve 21 and an overspeed governor valve 23 to the engine. A variable underspeed governor valve 26 is connected between the delivery of the pump 17 and the inlet to the engine. The pressure drop across the valves 21, 23 and valve 26 is maintained constant by a by-pass valve 32. The valve 23 is normally open and the fuel supply to the engine is controlled by the pilot lever 30 which is connected to the valve 21 through a cam 40 and follower 36. The valve 26 comprises a piston 48 which is connected to the fly-ball governor 44 by a stem 43 and which slides in a sleeve 49. The position of the sleeve is determined by the throttle lever 30 through a cam 53 and follower 52. The speed at which the underspeed governor operates thus varies with the position of the throttle lever. The application of the invention to a power plant in which two engines drive a single propeller is also described. In this arrangement, if one engine fails and is cut out, the fuel supply to the other engine will be increased automatically to drive the propeller at the minimum speed. The system may have combined with it means for controlling the fuel supply in accordance with the ambient conditions and the combustion gas temperature.