GB1246616A - Jet propulsion power plant - Google Patents

Abstract

1,246,616. Control apparatus for jet deflectors. ROLLS-ROYCE Ltd. 30 Jan., 1969 [7 Nov., 1967], No. 50554/67. Heading B7G. [Also in Division F1] A jet propulsion power plant for aircraft comprises a deflector member which is movable so as to deflect the jet stream, also a fuel control system having means to vary the flow of fuel between high and low values, there being auxiliary means connected to the deflector member so as to restrict the fuel flow to a low value when the deflector member is in a position between its terminal positions. The power plant shown comprises a pair of thrust reverser members 12 which are movable by actuators 15 between an inoperative position 13 in which they are clear of the jet stream J, and an operative position 14 in which they deflect the jet stream with a forward component for reverse thrust. A fuel supply system comprises a valve member 24 which is movable by the throttle control 19 between a minimum flow position 25 and a maximum flow position 26, the fuel passing through an auxiliary control 30 to the fuel burners 22B. The auxiliary control 30 comprises a spool valve 31 mounted for axial movement in a cylinder 31A the spool being connected through a lost motion device 43 to the reverser member 12. When the members 12 are in the inoperative position 13, the groove 33 of the spool is aligned with the fuel ports 32 so that the fuel flow is as determined by the throttle valve 24. Similarly when the reverser members are in the operative portion 14, the groove 34 of the spool is aligned with the fuel ports 32 and the fuel flow is again as determined by the throttle valve 24. But when the reverser members are in an intermediate position, the enlarged portion 35 of the spool is aligned with the fuel ports 32 so that whatever the position of the throttle 24 the fuel flow is limited by the enlargement 35. A locking means 38 is provided which when the enlarged portion of the spool is aligned with the fuel ports 32, is urged by spring means into the recessed portion 37 of the spool. The locking member 38 is disengaged from the recess 37 by means of a flange member on the throttle valve when the throttle is moved to a low setting 25. The lever 18 for controlling the thrust reverser is mounted on the throttle lever 19 and can only be moved when the throttle lever is in a low power position in which a spigot 47 on the lever 18 may engage a recess 48 in the throttle gate. The object of the invention is to ensure that should the thrust reverser be moved as a result of some failure to an intermediate position, the fuel flow is automatically reduced from a high value to a low value.