GB806207A - Improvements in or relating to governors, more particularly for gas turbine engines - Google Patents

Abstract

806,207. Gas turbines. BENDIX AVIATION CORPORATION. Nov. 8, 1955 [Dec. 22, 1954], No. 31929/55. Class 110 (3). [Also in Group XXIX] An engine speed governor, more especially for controlling the fuel supply to a gas turbine engine comprises fly weights 142 driven by the engine and acting on a valve member 176 which controls the pressure in a chamber 72 acting on a combined servo piston and fuel control valve 60. The member 60 reciprocates in a fixed sleeve 42 and has a control portion 64 coacting with ports 54 in the sleeve to control the flow of fuel from an inlet 24 to an outlet 17. Fuel under pressure also passes through a passage 110 and valve 112 to a chamber 70 where a pressure maintained at a constant value by the valve 112 acts on a piston portion 66 of the member 60 to bias the latter towards the right. Pressure fluid from the chamber 70 also passes through a passage 108 and restriction 118 to the chamber 72 where it acts on a piston portion of larger area than the portion 66. A leakage of pressure fluid from the chamber 72 through passages 120, 122 is controlled by the valve member 176 coacting with a seating 124 carried by the member 60 whereby movement of the valve member 176 is followed up by a corresponding movement of the member 60. A drain passage 100 leading from an annular groove 98 prevents the pressure in the chamber 72 from being affected by that in chamber 58. In the event of the member 60 failing to operate in response to operation of the valve member 176 an extension 178 of the latter, which has a lostmotion connection with the members 60, 124, operates the member 60 directly. A governor loading spring 162 is adjustable by an operator through a movable sleeve 160 slidable on a fixed sleeve 134. The degree of opening of the fuel valve 64 during acceleration of the engine is limited by a stop 86 which is adjustable by engine speed and compressor inlet temperature and coacts with an abutment 82 carried by the member 60. The abutment 82 also coacts with an adjustable minimum fuel flow stop 84.