Patent ID: 7258213

Claim:
A power transmission device comprising: a rotary input member adapted to receive drive torque from a power source; a rotary output member adapted to transmit drive torque to an output device; a torque transfer mechanism for transferring drive torque from said input member to said output member, said torque transfer mechanism including a friction clutch operably disposed between said input and output members and a clutch actuator for controlling adaptive engagement of said friction clutch, said clutch actuator including an electric motor, a drive gear driven by said electric motor, first and second face gears meshed with said drive gear for rotation in opposite directions, and an apply mechanism for varying the magnitude of a clutch engagement force exerted on said friction clutch in response to relative rotation between said first and second face gears; and a control system for actuating said electric motor so as to control the direction and amount of rotation of said drive gear.