Patent ID: 7059462

Claim:
A power transmission device comprising: a first rotary member adapted to receive drive torque from a source of torque; a second rotary member adapted to provide drive torque to an output device; a torque transfer mechanism operable for transferring drive torque from said first rotary member to said second rotary member, said torque transfer mechanism including a clutch assembly operably disposed between said first rotary member and said second rotary member and a hydraulic clutch actuation system operable for applying a clutch engagement force to said clutch assembly, said hydraulic clutch actuation system including a primary fluid circuit supplying a first fluid to an inlet of a pressure intensifier and a secondary fluid circuit supplying a second fluid from an outlet of said pressure intensifier to a pressure chamber for causing a clutch operator to apply said clutch engagement force to said clutch assembly; and a control unit for controlling actuation of a control valve in said secondary fluid circuit for regulating the fluid pressure supplied to said pressure chamber.