Patent attributes
A power system includes an electric motor, a transmission, and a differential gear system. The transmission includes a first gear that is mechanically connected to the electric motor, a second gear that has a rotation axis in common with the first gear and is mechanically connected to a differential gear casing of the differential gear system, and a plurality of pinion gears that mesh with the first gear and the second gear. The plurality of pinion gears are supported to be capable of rotating and not to be capable of revolving. One pinion gear out of the plurality of pinion gears is only mechanically connected to a rotation restricting mechanism that is switchable between an operating state and a non-operating state. The rotation restricting mechanism restricts rotation of the pinion gear in the operating state, and permits the rotation of the pinion gear in the non-operating state.