| 摘要 |
<P>PROBLEM TO BE SOLVED: To reduce strange sound and vibration in an electric four-wheel drive vehicle by stopping the rotor of an electric motor as quickly as possible when a vehicle speed exceeds predetermined one and rotation is not transmitted between the wheel and the electric motor. <P>SOLUTION: Since permanent magnets 130a and 130b are provided between the claw poles 111a, 111b, 112a, 112b of a claw pole rotor, the rotor trying to continue rotation with inertia when a vehicle speed exceeds predetermined one and rotation is not transmitted between the electric motor and the wheel, can be braked with magnetic force of the permanent magnets 130a and 130b. Consequently, strange sound or vibration is not generated even if rotation is not transmitted between the electric motor and the wheel. A big torque can be attained because a big amount of gap magnetic flux is obtained through saturation of the magnetic circuit in the claw poles 111a, 111b, 112a, 112b when the field current of the claw pole rotor is increased. <P>COPYRIGHT: (C)2008,JPO&INPIT |
