Patent ID: 6766889
Filing Date: 2004-07-27
Classification: B60K,F16H

Abstract:
A power transmission device comprising:a rotary input member adapted to receive drive torque from a power source; a rotary output member adapted to provide drive torque to an output device; a torque transfer mechanism operable for transferring drive torque from said input member to said output member, said torque transfer mechanism including a friction clutch assembly operably disposed between said input member and said output member and a clutch actuator for applying a clutch engagement force to said friction clutch assembly, said clutch actuator including a wedge fork having a stem segment with a gear rack and a tang segment with a tapered drive surface, a reaction block having a tapered reaction surface engageable with said tapered drive surface on said tang segment and an apply surface engageable with said friction clutch assembly, and an electric motor driving a pinion gear that is meshed with said gear rack on said stem segment of said wedge fork; and a controller for actuating said electric motor so as to control the direction and amount of rotation of said pinion gear which, in turn, controls the direction and amount of translational movement of said wedge fork, such movement of said wedge fork causes said tapered drive surface on said tang segment to slide relative to said tapered reaction surface for forcibly moving said reaction block relative to said friction clutch assembly so as to vary the clutch engagement force exerted by said reaction block on said friction clutch assembly.