Patent ID: 6733411
Filing Date: 2004-05-11
Classification: F16H

Abstract:
A differential assembly for a motor vehicle, said differential assembly comprising:a differential case to be rotated by an outside drive torque; at least one output shaft drivingly connected to said differential case; a friction clutch assembly for selectively engaging and disengaging said differential case and said output shaft; a hydraulic clutch actuator for selectively frictionally loading said clutch assembly, said actuator including a variable pressure relief valve assembly for selectively controlling said friction clutch assembly, said variable pressure relief valve assembly including: an electro-magnetic actuator; a pressure relief valve selectively controlled by said electro-magnetic actuator; and a transformer assembly for supplying an electrical current to said electro-magnetic actuator, said transformer assembly including a non-rotatable primary transformer unit and a rotatable secondary transformer unit, said primary transformer unit being stationarily mounted outside said differential case and connected to a source of electrical energy, said secondary transformer unit being mounted to said differential case, said secondary transformer unit being responsive to a magnetic field generated by said primary transformer unit to induce said electrical current to said secondary transformer unit for supplying said electrical current to said electro-magnetic actuator.