GB1259045A - - Google Patents

Abstract

1,259,045. Deflecting propulsion Jets. ROLLSROYCE Ltd. 23 March, 1970, No. 13963/70. Addition to 1,209,098. Heading B7G. A gas turbine front fan engine has an annular fan duct 15 between inner and outer casings 11, 12 spaced apart by aerofoil-shaped struts 13, the outer casing 12 having an apertured portion 22 traversed by axially extending beams 23. Guide vanes 24 are carried by the beams 23 and during reverse thrust direct the fan air from the duct 15 forwardly. Primary thrust reverser flap members 25 are radially movable between a thrust reversal position (shown in broken outline in Fig. 2) in which they block the fan duct 15 and force the fan air to pass out through the apertured portion 22, and a forward thrust position (shown in full outline in Fig. 2) in which they permit the fan air to flow through the fan duct 15 but block a major part (but not the whole) of the apertured. portion 22. A sleeve member 26 is movable axially of the outer casing 12 by means of hydraulic or pneumatic rams 27 (only one shown) between forward thrust and thrust reversal positions (shown in full lines and broken lines, respectively) to close or open the apertured portion 22. Alternate primary thrust reverser flap members 25 are pivotally connected to two additional flap members 31 which are pivotally connected to the primary members 25 about axes which are spaced from circumferentially opposite sides of the latter. In the thrust reversal position the additional members 31 lie in planes which extend radially of the outer casing 12 while in the forward thrust position they are disposed so as to form part of the outer circumference of the fan duct 15 and block that part of the apertured portion 22 which is not blocked by the primary members 25. Each of the primary members 25 is carried by two arms 32, each provided with a roller 33 movable in a fixed track 34. Each of the arms 32 is pivotally connected to one end of a respective strap 35 which is mounted on a pivot 36 carried by a fixed ring member 37. Each of a plurality of links 40 has one end 41 pivoted to the sleeve member 26 and another end 42 pivoted to a respective primary member 25. Accordingly, when the sleeve member 26 is moved axially downstream, all the primary members 25 are moved into the thrust reversal position. Each of the additional members 31 is pivotally connected to its primary member 25 by means of a link 43 and also by a pair of links 45, 46. A pivot pin 50 on which is mounted a bracket 51 extends between the links 45, 46 and the bracket 51 has spaced ears through holes in which extends a rod 54 which is pivotally connected at 55 to the respective link 40. By reason of this construction, when the primary members 25 are moved into the thrust reversal position, the additional members 31 are pivoted into the radial position shown in broken outline in Fig. 2. Thus, operation of the rams 27 effects movement of not only the sleeve member 26 but also, by way of the links 40 and rods 54, simultaneous movement of the members 25, 31 between the thrust reversal and forward thrust positions.