Patent ID: 7775060

Claim:
A drive unit for an electric vehicle, comprising: a motor; an inverter supplying alternating current electric power to the motor; a speed reducer reducing a revolution speed of a mechanical output of the motor, the speed reducer comprising a differential gear train distributing the mechanical output of the motor into left and right driving shafts; a structural member integrally holding the motor, the inverter, and the differential gear train; first refrigerant receiving heat of at least the motor and outputting the heat into the atmosphere, wherein the first refrigerant includes cooling water and passes through a first refrigerant passage having a first passage section and a second passage section, the first passage section in contact with at least the motor; second refrigerant receiving heat of at least the speed reducer and outputting the heat to the first refrigerant, a cooling performance of the first refrigerant being higher than a cooling performance of the second refrigerant, wherein the second refrigerant passes through a second refrigerant passage; and a heat exchanger transferring the heat of the second refrigerant to the first refrigerant, the heat exchanger being integrally built in the structural member, being disposed under the drive unit constituted by the motor, the inverter, and the differential gear train, and including the second passage section being disposed within an inside of the second refrigerant passage, and wherein the first passage section is disposed away from the second refrigerant passage.