| 摘要 |
A DC permanent magnet motor includes a pole piece (14 or 16) which has notched leading and trailing edges (32) which present alternately sloping edges (24) to an armature bar (24) passing thereunder whereby to substantially reduce or eliminate cogging. The edges (34) are preferably substantially straight and the slope of the alternate edges may be the same or different. The length (L) of each notch measured from the edge of the inner curved surface (35) of the pole piece (14 or 16) in a circumferential direction is preferably equal to the distance between the corresponding radially outermost points on adjacent armature bars (24). |
