Patent attributes
A first gear train couples one shaft with the left axle or the right axle. The one shaft is one of two shafts which are not coupled to the reduction gear. The other one of the two shafts is coupled with one element which are not coupled to the first gear train among three elements of the differential case, the left axle and the right axle. The planetary gear mechanism, first gear train and second gear train have a gear ratio by which rotation of a motor stops when the differential apparatus does not perform differential operation and total torque of the left axle and the right axle when torque of the motor is applied does not change. The motor is disposed at one side in a vehicle widthwise direction with reference to the differential apparatus, and a planetary gear mechanism is disposed at the other side.