GB855826A - An improved speed governing device for an engine-driven fuel pump - Google Patents

Abstract

855,826. Governors. ARMSTRONG SIDDELEY MOTORS Ltd. Aug. 27, 1959 [Aug. 28, 1958], No. 27584/58. Class 57. An engine speed-governor associated with an engine-driven fuel pump 1 comprises two governors 26, 27 each arranged to be driven simultaneously by the pump through separate driveshafts 6, 7 and arranged to operate valves 38, 44 controlling the flow of fuel from the pump to the engine. As shown applied to the fuel system of a gas turbine engine, the governors 26, 27 are driven from the driving-shaft 8 of the pump, the shaft 6 having on one end a gear 11 engaging with internal splines formed in the shaft 8 and, on the other end, a gear 30 engaging a gear 31 on the shaft 32 of the governor 26; the shaft 7 is driven by a gear 14 mounted on one end thereof engaging with an external gear 12 formed on the shaft 8, the other end of the shaft 7 having splines engaging with the driving-shaft of the governor 27. In operation, the governor 27 which is adjusted to suit the normal speed range of the engine, controls, through a pivoted lever 35, the valve 38 arranged between ducts 39, 40 carrying fuel from the outlet 19 of the pump 1 to the engine burners. In the event of the engine overspeeding, the governor 26, which is adjusted to a higher speed than the normal maximum, operates the valve 44 and thereby returns fuel to the pump inlet through a spill return chamber 46. The shafts 6, 7, 8 may have reduced portions 50, 51, 52, respectively, to provide weak links so that, in the event of an overload causing one of the portions, to break, the fuel supply will still be controlled by one or other of the governors 26, 27.