HYDRAULIC ACTUATING SYSTEM

摘要

PROBLEM TO BE SOLVED: To provide such a hydraulic actuating system that each gear engaged actuator is controlled by one common solenoid actuated control valve. SOLUTION: A change-over valve 300 disposed between a gear engaged control valve 146 and the first 114 and the second gear engaged actuator 115 connects the first gear engaged actuator 114 to the gear engaged control valve 146 and the second gear engaged actuator 115 to a reservoir 278 in first position and connects the second gear engaged actuator 115 to the gear engaged control valve 146 and the first gear engaged actuator 114 to the reservoir 278 in second position and the change-over valve 300 allows to be shifted from the first position to the second position if pressure in a clutch actuator is a lower value than first predefined value and is a higher value than second predefined value.