Clutch with magneto-rheological operator for transfer cases and the like

摘要

A multiple disc clutch pack includes a pilot magneto-rheological operator which controls operation of an associated ball ramp operator which, in turn, compresses a clutch pack to selectively transfer torque between and input member and an output member. The pilot operator includes an electromagnetic coil disposed proximate a magneto-rheological fluid contained within a chamber of a pilot clutch. Activation of the electromagnetic coil creates a magnetic flux which travels through the magneto-rheological fluid and couples the fluid clutch members, creating drag and relative rotation between members of the ball ramp operator. Such relative rotation of the ball ramp operator selectively compresses the clutch pack and transfer torque from the input member to the output member.