Patent ID: 7624852

Claim:
A decoupler assembly for transferring rotational torque between a drive shaft and an endless drive element of an automotive engine, said decoupler assembly comprising: a drive hub configured to be fixedly secured to the drive shaft; a pulley rotatably mounted on said drive hub and adapted to be drivingly engaged with the endless drive element; a spring shell operatively coupled between said drive hub and said pulley for selective rotation therewith, said spring shell having a radial rim element, said radial rim element frictionally engaging and supporting said pulley; at least a pair of biasing members elastically coupling said spring shell and said drive hub isolating oscillatory vibrations therebetween; and a clutch element seated between said spring shell and said pulley selectively transferring rotational torque from said drive hub to said pulley and enabling overrunning of the pulley relative to said drive hub, wherein said clutch element includes a plurality of helical coils in frictional engagement with said pulley and an end coupled to said spring shell, said clutch element expanding against said pulley upon driving rotation of said drive hub relative to said spring shell selectively coupling said drive hub and said pulley, wherein said radial rim element has a helical contour corresponding to and supporting said helical coils of said clutch element.