GB759695A - Improvements in or relating to speed-sensitive control devices - Google Patents

Abstract

759.695. Governor transmitting mechanism. ROLLS-ROYCE, Ltd. Oct. 8 1952 [Oct. 8, 1951], No. 23426/51. Class 57 [Also in Groups XXIX and XXXV] A fuel supply system for a jet-engine comprises a pump impeller 16 driven from the engine shaft 10 drawing fuel from a tank along a conduit 18 and delivering it along a conduit 19 past a throttle valve 20 to the engine combustion chamber. The valve 20 comprises a plugged rotatable valve tube 21 having a series of inlet ports 23 whose area is not changed by rotation and a metering outlet port 24 whose area is controlled by rotation of the cylinder. A minimum flow orifice 23a is provided. The end of the valve tube carries a cylindrical head 25 having a radial nozzle 26 directed towards a receiving inlet 27 in a flange 29 of the valve tube, the fluid returning through ducts 41a, 41b to the duct 18. The pressure induced in inlet 27 acts on a Bourdon tube 30 connected between this flange and the casing to rotate the valve tube to control the aperture of outlet port 24. A steel cup 32 mounted on a spindle 34 has an aperture 33 in its edge through which the jet from the nozzle 26 passes. The spindle 34 which is resiliently restrained by a pair of magnetic devices 35, 36 (see Group XXXV), carries an eddy-current coupling member 38, the force on which depends on the speed of the engine shaft 10. In operation, if the engine speed becomes excessive, the increased torque on coupling member 38 turns the spindle 34 and cup 32 displacing the slot 33 to reduce the pressure due to the jet 26 on the Bourdon tube 30. Consequent rotation of the valve tube 20 closes port 24 and reduces the supply of fuel to the engine. Specifications 716,254 and 716,255 are referred to.