GB870587A - Thrust spoiler for a jet propulsion engine - Google Patents

Abstract

870,587. Deflecting propulsion jets on aircraft. GENERAL MOTORS CORPORATION. Nov. 27, 1959 [Nov. 28, 1958], No. 40369/59. Class 4. In a thrust-spoiler for a jet propulsion engine, wherein the jet nozzle is an annula duct which is closable by flaps attached to the outer wall of the duct, the tail part of the inner wall of the duct has normally covered thrust-spoiler vanes and is movable axially of the duct in the rearward direction to expose the vanes and to open an inlet in the inner wall upstream of the closure flaps which are then in closed position so that the gas of the propulsive jet can enter that inlet, flow within the inner wall, and emerge through the spoiler vanes downstream of the flaps. The propulsive gases flow through an annular duct 30 formed between an extension 24 of the engine casing and the well of an inner cone 28. Extension 24 carries a plurality of circumferentially overlapping flaps 26 each pivoted at 32 and formed with a cam track 36 to engage a pin 38 mounted on an annular shroud 40 movable by a jack 46 to swing the flaps 26 from the position of Fig. 1 to the position of Fig. 2 in which their trailing edges abut the outer wall of cone 28. The construction of cone 28 provides an annular cavity 74 formed aft of structure 1 between an inner wall 60, end wall 62 and an outer wall comprising a fixed part 97 and relatively movable parts 72 and 80. This associated structure is axially movable on rollers 55, carried by fixed cone structure 50, 52, by means of jacks 66. Wall 72 is apertured top and bottom for-sets of guide vanes 78 and it carries tracks 81 for roller assemblies 82 mounted on part 80 by means of circumferential channels 85. Welded to the forward channel 85 at each roller assembly is a rod 92 slidably mounted in an apertured flange 96 attached to wall part 97, the rod having a cross-pin 98 which can bear against flange 96 to limit rearward movement of the rod. In operation, jacks 46 and 66 are operated jointly to swing flaps 26 to the position of Fig. 2 and to move aft parts 60, 62, 72 and 78 of the cone 28. During this movement parts 72, 78 move relatively to part 80 which is subsequently also moved aft by the forward end of track 81 engaging the forward roller assembly 82, rearward movement of part 80 being limited by the engagement of cross pin 98 with flange 96. This places cavity 74 in communication with duct 30 through exposed apertures 79 so that the propulsive gases may be deflected by flaps 26 into the cavity 74 to emerge outwardly through vanes 78 in a forward direction.