Abstract: The invention provides an accessory drive that is a combination of mechanical and hydraulic components that accepts variable speed input power from a prime mover or engine and transmits that power in a very efficient manner to the output of the device to drive ancillary engine accessories (e.g., cooling fans, generators, water and fuel pumps, etc.). The accessory drive system allows the output speed of the drive and the speed of the engine accessories to be controlled in a manner that minimizes power consumption of the accessories and drive system.

Abstract: A control mechanism is provided which feathers the propeller blade pitch during stopping and stores restart energy in the blade pitch governor mechanism. Deceleration to the feathered mode is aided by the airstream. During restart, excess stored energy is used to increase reliability, but is then dissipated mechanically, as by a flywheel mechanism, to maintain low internal impact stresses. More specifically, where single governor spring is used for controlling the pitch of all propeller blades, a braked ball screw device is used to compress that spring during stoppage. Upon restart, the governor spring expands and causes blade pitch change. The ball screw arrangement then dissipates a large portion of the excess energy through torque transmission to mechanical components.

Abstract: An actuator includes a main shaft (16) at the input of a speed reducing gear unit (29-32) which carries an overtravel stop mechanism. The grounded stops (68) are adjustable by a worm gear (72) to allow a near infinite resolution of the position for the overtravel stop of the driven member (16). Rotating stop members (52) are mounted for translation along the main shaft (16). When traveling nut (44) engages a cam surface (60), cam follower (56) translates the normally rotating stop members (52) in a direction opposing the bias force of a compression spring (36) into a stop condition against the grounded fixed stop (68) on wheel (50).