GB1105926A - Improvements in systems for controlling windmilling of gas turbine engines of multi-engined aircraft - Google Patents

Abstract

1,105,926. Latch fastenings; similarly operated fastenings. GENERAL ELECTRIC CO. 9, June, 1965, No. 24362/65. Heading E2A. [Also in Division Fl] A latching mechanism to lock compressor stator vanes of an aircraft gas turbine engine in the fully closed position to prevent windmilling of the engine in the event of shutdown includes an annular vane operating ring 36 movable circumferentially about the engine casing 20 and pivotally connected to individual vanes (24, Fig. 2, not shown) by links (32). A bracket 58 attached to the ring 36 has pivoted thereon a bellcrank 54, one arm 59 of which is pivoted to an actuating rod 45 controlled by an electrically driven mechanical ram (44, Figs. 4, 5, not shown), and the other arm 62 of which carries a roller 63 and a pivoted locking member 65. In the fully open position of the vanes (Fig. 6, not shown), roller 63 and a projection 75 on bracket 58 respectively engage stops 52, 51 on a bracket 48 fixed to the casing 20. In the event of shut down of the engine, the pilot manually applies a signal to actuate rod 45 which rotates ring 36 clockwise to the position shown to close the stator vanes. In so doing bellcrank 54 pivots about point 56, roller 63 rides along cam surface 50 and locking member 65 engages under the action of spring 74 a lip 72 on bracket 48 to lock the vanes in the closed position. The vanes can only be reset to the open position by operation of a switch when the aircraft is on the ground.