GB694316A - Improvements in speed limiting mechanism for continuous combustion turbine engines - Google Patents

Abstract

694,316. Gas turbine plant DOWTY EQUIPMENT, Ltd. Aug. 23, 1951 [May 23, 1950], No. 12914/50. Class 110(iii) [Also in Group XXIX] Means for limiting the maximum speed of an aircraft continuous combustion turbine engine consists of a pressure-balanced device controlling either a variable-stroke fuel pump or a by-pass of a fixed-stroke pump, a vent 11, Fig. 1, from the pressure-balanced device, and a vent valve 12 pivoted at 14 and influenced in the vent-opening direction, to limit the fuel flow to the engine, by a bellows 26 subject internally to a pressure generated by an engine-driven centrifuge, and in the vent closing direction by an adjustable spring 29 and by a plunger 31 acting through a pivoted lever 20 and subject to a pressure which diminishes with altitude. By suitably choosing the diameter of the plunger 31 the maximum engine speed may be maintained constant at all altitudes or caused to increase or decrease with altitude to a required extent. The pressure which diminishes with altitude may be obtained from the fuel supply conduit to the burners of the engine, or from a spill line in the case of spill-type burners. or it may be ram pressure. In a modification, the vent valve 35, Fig. 2, is loaded in the opening direction by the pressure which is a function of engine speed acting on a diaphragm 40, and in the closing direction by a spring 43 and by the pressure which diminishes with altitude acting either on a shoulder 38 or on both the shoulder 38 and a shoulder 39 depending upon the setting of a manually-operable valve 52. This arrangement of stepped plunger may be employed instead of the plunger 31, Fig. 1.