| 摘要 |
PROBLEM TO BE SOLVED: To provide a permanent magnet type brushless motor for an electric power steering apparatus which achieves compatibility between low torque pulsating current and reduction in the loss of eddy current of a rotor, and obtains good steering feeling, and at the same time retards heating of the rotor, thereby enabling prevention of demagnetization of magnet and reduction in the remaining magnetic flux density. SOLUTION: The apparatus includes a shaft 21; a rotor 20 provided around a rotating shaft 21, and having a plurality of permanent magnets 22 for forming a plurality of magnetic poles; and a stator 10 having a stator core 11 provided opposite to the rotor 20 and having a plurality of teeth 11a provided projectingly in the direction of central shaft and forming grooves 11b for winding between adjacent teeth 11a, and armature windings 12 wound concentratedly around the teeth 11a. Assuming the number of magnetic poles of the rotor 20 to be P and the number of grooves between the teeth 11a of the stator 10 to be N, the relationship 1<N/P≤1.2 is obtained, and fraction N/P is not irreducible fraction. COPYRIGHT: (C)2003,JPO |
