GB1253071A - - Google Patents

Abstract

1,253,071. Reversing thrust of propulsion Jets. ROLLS-ROYCE Ltd. 12 Sept., 1969 [14 Sept., 1968], No. 43824/68. Heading B7G. A jet nozzle comprises a main duct divided into two branch ducts 11 by a centre body 12 which is provided in respect of each duct 11 with a flap 19 movable from a first, inoperative position within a recess 23 (Fig. 1, not-shown) into a second, jet spoiling position (Fig: 2) and a third, thrust reversing position (Fig. 3). Means for moving the flap from the first to the second position comprise a piston and cylinder fluid pressure motor 24 whose crosshead 25 is connected by a link 26 to a respective flap by a pivot 27. The flap is supported on the body 12 for arcuate movement about a pivot 30 connected by a link 36 to a pivot 27. For movement into the third position the flap, supported on the links 26, 36, is pivoted about the pivot 27 by a fluid pressure motor 33 connected between the pivot 30 and a pivot 34 on an arm 35 attached to the flap. The flap includes an extension 37 of its surfaces which is provided with a bell-crank lever 38 connected by a link 39 to the link 36, such that when the flap is moved from second to third position the extension 37 is moved out of a position of alignment with the flap surfaces (Fig. 2) into a position forming a bend 40 for the surface 32 to assist in imparting a further reverse component to the gas flow. The flap may be moved directly from first to second, second to third and, if necessary, first to third positions, and may be arranged so that it is in a position approximately perpendicular to the engine axis 18 in order to act as an air brake as well as a jet spoiler.