Hydrostatic continuously variable transmission

摘要

In a hydrostatic continuously variable transmission comprising a swashplate type hydraulic pump having a pump swashplate and annularly arranged pump plungers whose suction and discharge strokes are provided by the pump swashplate, a swashplate type hydraulic motor having a motor swashplate and annularly arranged motor plungers whose expansion and shrinkage strokes are provided by the motor swashplate, and a hydraulic closed circuit formed between the hydraulic pump and motor, the middle point of a discharge region of the hydraulic pump is angularly delayed at a given angle in a direction of rotation of the hydraulic pump relative to a tilting axis of the pump swashplate, and/or the middle, point of an expansion region of the hydraulic motor is angularly advanced at a given angle in a direction of rotation of the hydraulic motor relative to a tilting axis of the motor swashplate. Further, a suction region of the hydraulic pump is set at an angle larger than that of a discharge region thereof, and/or a shrinkage region of the hydraulic motor is set at an angle larger than that of an expansion region thereof.