Patent ID: 7360633
Filing Date: 2008-04-22
Classification: F16H

Abstract:
1. A lockup device arranged in a hydraulic torque transmission device having a front cover configured to receive a torque, an impeller fixed to the front cover and forming a fluid chamber filled with working fluid, and a turbine opposed to the impeller, and located in a space between the front cover and the turbine to couple mechanically the front cover and the turbine together, the lockup device comprising: a damper mechanism having a first friction plate being unrotatable and axially movable with respect to said drive member; a second friction plate being unrotatable and axially movable with respect to the front cover, and arranged axially on a turbine side of said first friction plate; a piston being rotatable with respect to the turbine, being axially movable relative to the drive member by a predetermined distance, having a pushing portion arranged axially closely to the turbine side of said second friction plate, and being movable axially according to changes in pressure of the working fluid; and a coupling member unrotatably and axially elastically coupling said drive member and said piston together.