Crankshaft decoupler

摘要

A decoupler assembly (20) is provided for transferring rotational torque between a drive shaft (16) and a drive belt (18) of an automotive engine. The decoupler assembly includes a drive hub (40) configured to be fixedly secured to the drive shaft. A pulley (22) is rotatably coupled to the drive hub (40) and adapted to be drivingly engaged with the belt (18). A spring shell (70, 100) is operatively coupled between the drive hub and the pulley for selective rotation therewith and a biasing member (130) is operatively coupled between the spring shell and the drive hub for isolating oscillatory vibrations between the drive hub and the pulley caused by rotation of the drive shaft. A clutch element (140) is seated between the spring shell (70, 100) and the pulley (22) for selectively transferring rotational torque from the drive hub to the pulley. The pulley (22) includes an inner clutch surface (26) and the clutch element includes a plurality of coils in frictional engagement with the inner clutch surface and an end coupled to the spring shell for expanding the coils against the inner clutch surface upon rotation of the spring shell with the drive hub to selectively transfer torque between the drive hub (40) and the pulley (22).