Abstract: A hydromechanical drive wherein a prime mover drives an input shaft which, in turn, can drive a coaxial output shaft by way of a clutch or transmission having one or more axial piston pumps. The pressure and/or rate of fluid flow in the pump or pumps is adjustable by one or more valves or by one or more tiltable wobble plates in response to signals from one or more adjusting devices which receive signals from an electronic control circuit. The latter further receives signals from tachometer generators which monitor the RPM of the input and output shafts, from a gauge which monitors the pressure in the pump or pumps, from the valve or valves, or from the adjusting devices(s) for the tiltable wobble plate(s).

Abstract: A differential gearing wherein a hydrostatic motor is flanked by two mechanical transmissions. The motor is an axial piston motor, a radial piston motor or a gear motor, and its main driving member rotates the input element of one of the transmissions. The rotary housing of the motor transmits torque to the input element of the other transmission. The motor and the transmissions can be installed in a common case, in discrete cases or directly in the hubs of the respective driven wheels.