Disc rotor retraction system

摘要

A disc rotor blade retraction system includes a main blade spar (22) incorporating a hydraulic cylinder (54) and having a screw thread (34). A ball screw (24) is concentrically carried within the main blade spar and is operably connected to a ball nut (60) which has an outboard end connected to an intermediate spar (26) with a hydraulic piston (62) received for reciprocation in the hydraulic cylinder. A first geared actuator (20) engages the ball screw and a second geared actuator (30) engages the main blade spar screw thread. A hydraulic fluid accumulator (74) providing pressurized hydraulic fluid is connected to an outboard end of the hydraulic cylinder and a controller actuates the first and second geared actuators.