Patent attributes
In a hydrostatic continuously variable transmission, a hydraulic pump is linked to a hydraulic motor by a hydraulic closed circuit to change the capacity of the hydraulic motor so as to change the speed of a motorcycle continuously. A clutch device comprising a clutch valve for connecting and disconnecting a high pressure side oil passage and a low pressure side oil passage constituting the hydraulic closed circuit. A governor mechanism for generating governor force corresponding to the input rotation speed of the hydraulic pump and applying this governor force in the closing direction of the clutch valve. A spring for giving urging force in the opening direction of the clutch valve, and a buffer mechanism having a variable oil chamber and an oil pool chamber for easing the opening and closing movements of the clutch valve activated according to the governor force and the urging force.