Hydraulic clutch assembly

A hydraulic clutch assembly equipped with a spring-drive hydraulic clutch, said hydraulic clutch comprising:

• a gear rotatably mounted on a transmission shaft and a clutch cylinder fixedly mounted on said transmission shaft;
• a first group of friction elements respectively and relatively non-rotatably supported on said gear and said clutch cylinder in such a manner as to be slidable along an axis of the clutch;
• a pressure disk disposed opposite to said first group of friction elements;
• a spring for moving the pressure disk towards the first group of friction elements to bring the friction elements into engagement with each other;
• a piston disposed in such a manner as to be slidable along the axis of the clutch on the opposite side of the pressure disk with the first group of friction elements there between, thereby forming a hydraulic fluid chamber within the clutch cylinder;
• an operation disk disposed in such a manner as to be slidable along the axis of the clutch between the piston and the first group of friction elements;
• and
• an interlocking rod extending along the axis of the clutch for interlocking the operation disk with the pressure disk in such a manner as not to be relatively movable with respect to each other;
• wherein
• said pressure disk is moved away from the first group of friction elements through the operation disk and the interlocking rod by an effect of hydraulic pressure acting on the piston, so that the friction elements are released from engagement with each other;
• a hydraulic-drive hydraulic clutch;
• said hydraulic-drive hydraulic clutch including;
• a second gear rotatably mounted on the transmission shaft so as to be positioned opposite to the gear with the clutch cylinder therebetween;
• a second group of friction elements, said first and second friction elements respectively supported on the second gear and the clutch cylinder in such a manner as to be slidable along the axis of the clutch and relatively non-rotatable thereto;
• a second piston disposed opposite to said piston with a partition wall therebetween, said partition wall formed in the clutch cylinder, said second piston being slidable along the axis of the clutch;
• and
• a second spring for biasing said second piston away from the second group of friction elements;
• wherein
• the friction elements can be brought into an engaged state with each other by having hydraulic pressure acting on the second piston;
• and
• the transmission shaft forms a single operational fluid passage for feeding and discharging there through pressurized fluid to the hydraulic-drive hydraulic clutch and the spring-drive hydraulic clutch, respectively.