HYDRAULIC PUMP/MOTOR WITH EPICYCLIC GEAR CONTROL

摘要

A positive displacement hydraulic pump/motor (1) assembly (1) includes a rotary cylinder block (3) a circular array of cylinders (6) around a central axis (5) with corresponding pistons (10) disposed within. Drive shaft (12) extends through a bore (13) and rotates the cylinder block (3) while a stationary valve plate (20) having a valve face (21) mating with a complementary mating surface (22) formed on the cylinder block (3). The valve plate (20) provide for inlet and outlet ports for the fluid communication with a source of hydraulic fluid and a hydraulic load. A coupling mechanism incorporating an epicyclic gear train (30) is operable in an engaged mode to connect the drive shaft (12) to the cylinder block (3).