DUAL HYDROSTATIC DRIVE TRANSMISSION

摘要

DUAL HYDROSTATIC DRIVE TRANSMISSION A hydrostatic transmission includes a mechanically driven hydraulic pump connected in hydraulic circuit with first and second hydraulic motors. The hydrostatic outputs of the first and second motors are respectively applied to the ring and sun gears of a planetary gear set whose carrier constitutes the transmission hydrostatic output. Acceleration under low speed, high torque conditions is achieved by varying the displacements of the pump and second motor, while the first motor is removed from the hydraulic circuit and the ring gear is braked. At an appropriate shift point, the first motor is inserted into the hydraulic circuit and the ring gear is released, such that further acceleration is achieved by varying the displacements of the pump and both motors in coordination.