Reductions in weight, frontal area and overhang moment in an aircraft engine gear box and electrical generating system are achieved in a construction including a gear box housing 20 provided with an input shaft 16 connectable to a power take-off 12. A differential 76 is disposed within the housing 20 and includes a carrier shaft 72 mounting meshed planet gears 82, 84. The differential includes a control ring gear 88 to mesh with the planet gear 84 and an output ring gear 92 meshed with the planet gear 82. The carrier shaft 72 is coupled to the input shaft 16. A hydraulic speed trimmer 54 is mounted on the exterior of the housing 20 and includes two pump/motor units 124, 128, each having a shaft 108, 110, extending into the housing 20 to be respectively connected to the carrier shaft 72 and the control ring gear 88. A generator 102 is mounted on the gear box housing 20 and includes a shaft 100 extending into the interior 22 of the housing 20 to be coupled to the output ring gear 92.

A hydro-mechanical power transmission for vehicles wherein optional two of the three elements of a planetary gearing serve as an input portion and an output portion, and the other element is driven at a steplessly variable speed by a static hydraulic speed change device which is operable by the input portion or the output portion. A change-over device is provided in a power transmission system for the speed change device to drive the other element in different speed ranges by switching the change-over device. For running on the road, the speed is widely variable from low to high, while for working, the running speed is finely adjustable within one of the speed ranges.

This invention relates to an integrated drive generator of the type employed onboard aircraft for power generation and prime mover starting. Prior art integrated drive generators which provided for a prime mover starting mode drove a prime mover through a constant speed transmission in order to provide motive power to the engine. The present invention provides a power path for prime mover starting which couples the motor/generator directly to the prime mover and decouples the motor/generator from the transmission by means of properly oriented one-way clutches. The integrated drive generator includes in combination in input/output shaft, and motor/generator having a rotor shaft, a constant speed transmission having an input and an output, a start power path coupling the motor/generator rotor shaft to the input/output shaft whereby the motor/generator, functioning as a motor, drives the input/output shaft as an output shaft, bypassing the transmission, to thereby start the prime mover coupled to the input/output shaft, and a generate power path coupling the input/output shaft to the transmission input and coupling the transmission output to the motor/generator rotor shaft whereby the prime mover drives the motor/generator as a generator at constant speed through the input/output shaft, functioning as an input shaft, and the transmission to produce constant frequency electrical power from the motor/generator for aircraft electrical equipment.

The problem of providing a dual redundant load path which is not vulnerable to a single point failure at the output of a motor shaft is solved by a dual redundant load path motor system, particularly for use in aircraft actuation systems. A motor (22) has a rotor (34) extending entirely therethrough to define first and second output drives (38 and 40) at opposite ends (34a and 34b) of the rotor. First and second output shafts (46 and 48) are coupled to the opposite ends of the rotor. The output shafts are located at a common end of the motor, and one of the output shafts (48) is coupled through a connecting shaft (68) to the end of the rotor at the opposite end of the motor. The connecting shaft runs generally parallel to the rotor.