Thrust reversing device for jet aircraft engines

A thrust reversing device for a jet aircraft engine, comprising:

• a pair of semi-shells hinged to a wall of a discharge nozzle extending along a nozzle axis and displaceable between retracted and deployed positions, the semi-shells defining a wall of the nozzle deflecting forward a jet output exiting the discharge nozzle in the deployed position and being formed with respective terminal edges;
• actuators consisting of two actuating piston and cylinder units mounted externally on opposite sides of the wall of the nozzle for displacing the semi-shells between the retracted and deployed positions, each of the units including a respective cylinder body and a respective piston movable in the body and operatively connected with the respective semi-shell;
• and
• a collar including two longitudinal lugs extending forward and free to slide on the discharge nozzle parallel to said nozzle axis, said lugs being operatively connected with respective ones of the pistons to be movable axially therewith and simultaneously with the semi-shells between fore and aft positions of the collar, the collar being formed with a leading edge lying complementary to the terminal edges of the semi-shells upon simultaneous displacing of the collar into the fore position and the semi-shells into the retracted positions, said collar having a trailing edge defining a termination circular profile of the nozzle in a plane extending substantially perpendicular to the axis of the discharge nozzle.