| 摘要 |
PURPOSE:To enable the both pulsating torque and cogging torque to be reduced, by selecting various factors so that the ratio of cogging period to skew pitch of a permanent magnet section or an armature section may be fixed in the desired range. CONSTITUTION:On an electric machine wherein the greatest common divisor between the magnetic pole quantity P of a permanent magnet field magnet section 1 and the quantity m of salient poles 51-53 for windings is not P and wherein auxiliary grooves 8c1-8e3 are provided on the surface of the salient poles 51-53 for the windings, the ratio of the pitch of winding grooves 8a1-8b3 between the magnetic salient poles to the pitch of the auxiliary grooves 8c1-8e3 is shown roughly by integral numbers in the whole circumference. And if the least common multiple between the total number NR of the values and the magnetic pole quantity P of the permanent magnet field magnet section 1 is shown by L, the pitch of 1/L in the whole circumference is regarded as cogging period, and so when the skew pitch is set by 1/L in the whole circumference, various factors are selected so that the value 1/L may come to 0.5/L-1.5/L. |
