HIGH-EFFICIENCY, LARGE ANGLE, VARIABLE DISPLACEMENT HYDRAULIC PUMP/MOTOR

摘要

A variable displacement hydraulic/pump motor has a yoke with a pair of shafts aligned to define a yoke pivot axis and connected to a valve plate therebetween having intake and discharge apertures. A rotatable cylinder barrel has piston cylinders open at one end to receive a piston head and opening through fluid ports at another end, flush against the valve plate surface. A drive block is mounted on an input/output shaft for rotation about a central, axis of rotation inclined at an angle relative to the longitudinal axis of the cylinder barrel which may be changed by a drive engaging the yoke at a point near its pivot axis. Loads on bushings supporting the yoke shafts are reduced by providing radially extending fluid ports in the shafts and in communication .with the intake and discharge apertures of the valve plate.