Patent ID: 7472770

Claim:
A hub unit for use in electrically movable wheels which has a motor comprising a stator and a rotor, and a hub enclosing the motor therein and to be rotatingly driven by the rotation of the rotor, the hub unit comprising: a motor housing comprising the stator and pair of end plates, the end plates adapted to tighten-up the stator and a cooling means for cooling the motor with rotation of the hub, the cooling means comprising: a pump mechanism operable to discharge air from inside the hub to outside the hub, the pump mechanism being fixed to the hub and rotatable integrally with the hub, an inlet air port adapted to allow outside air to enter therethrough to the hub and into the motor, the inlet air port being formed through the motor housing, and at least one projection portion extending from an outer periphery of the motor housing at a position substantially aligned with the path of rotation of the pump mechanism, said projection portion adapted to operate the pump mechanism when the pump mechanism contacts said projection portion by rotation of the hub.