Abstract: A power transfer mechanism incorporating a planetary or epicyclic gearset which may be shifted manually between high and low range conditions for direct drive and reduction ratio drive modes. The ring and planet gears are unloaded in the direct drive mode, thus avoiding vibration and wear commonly experienced when running locked-up. The mechanism may be incorporated in a multiple path drive system comprising a transfer case disposed between a source of input torque and a pair of drive axles, wherein torque is transferred directly to one drive axle and automatically to the other drive axle, when required, through a double-acting overrunning clutch.

Abstract: A power transfer mechanism incorporated in a multiple path drive system comprising a transfer case disposed between a source of input torque and a pair of drive axles. In one mode, torque is transferred directly to one drive axle and automatically to the other drive axle through a double-acting overrunning clutch when required. In another mode, torque is transferred to both drive axles in a locked-up condition.