Patent ID: 8033943
Filing Date: 2011-10-11
Classification: B60K,F16C,F16H

Abstract:
1. An in-wheel motor driving unit for driving a wheel via a speed reducer, said driving unit comprising: an electric motor having a rotor; a rotary shaft having its end connected to the electric motor to be rotated by the rotor of the electric motor, said rotary shaft including an eccentric portion; internal teeth; an external gear rotatably supported by the eccentric portion of the rotary shaft and including external teeth formed on an outer periphery of the external gear, said external teeth being fewer in number than the internal teeth, and having a trochoidal profile; a torque transmission configured to convert the rotation of the center of the external gear about the axis of the rotary shaft when the eccentric portion eccentrically rotates relative to the rotation of the external gear about its own axis, to thereby transmit power; and rolling elements disposed between an inner member formed with a raceway and an outer member formed with a raceway; wherein each of the internal teeth comprises an outer pin and a roller rotatably supported by the outer pin; and wherein said roller of each of said internal teeth comprises a needle bearing.