Thrust reverser for fan type jet propulsion engines

Claim 1

A thrust reverser for a fan-type jet propulsion engine having a casing wall and a fan concentric therewith and extending radially beyond said wall, said thrust reverser comprising: a cowling surrounding said fan and spaced from said casing wall to form an annular fan duct, said cowling being split and separated into stationary forward and aft cowl parts fixed relative to each other to provide an annular opening therebetween, said forward and aft parts forming a portion of inner and outer flow surfaces for said cowling, a ring structure having a plurality of flow reversing guide vanes, said ring structure being disposed within said annular opening and being interconnected with said forward and aft cowl parts of said cowling, a translatable sleeve sectiOn disposed between said forward and aft cowl parts when in cruise position, said sleeve section having a rigid outer wall slidable over said fixed aft portion and a collapsible inner wall, both of said outer and inner walls of said sleeve section forming another portion of the outer and inner flow surfaces respectively when in cruise position, said collapsible inner wall comprising a plurality of peripherally disposed blocker flaps of which the adjacent sides of each when in cruise position are overlapped by respective fillet flaps, said blocker flaps being hinged to the aft cowl part for pivoting thereabout, each of said blocker flaps being formed in two sections hinged directly together at the midlength of the flaps so that the sections can collapse upon themselves, said blocker flaps further being hinged at their upstream ends to said rigid outer wall, each of said fillet flaps being pivotally connected at each side of its upstream end to the upstream end of a respective blocker flap and axially slidably connected to said ring structure, the arrangement being such that when said translatable sleeve section translates over said aft cowl part so as to expose the guide vanes of said ring structure, said collapsible inner wall of blocker flaps collapses and pivots across said fan duct to block passage of fan air therethrough and said fillet flaps translate axially downstream in a direction substantially parallel to said fan duct and between adjacent edges of said blocker flaps, thus fully exposing said vanes to the flow of fan air in the fan duct.