| 摘要 |
<p>An electric machine comprises a soft-magnetic first part (11) having a plurality of salient poles (14) which are spaced-apart along a first pole row (R), a second part (16) comprising a plurality of pairs of permanent-magnetic poles of alternating polarities arranged in a second pole row (P) which extends along the first pole row (R) in confronting relation thereto, bearing means supporting the first and second parts (11, 16) for relative movement in the direction of the first and second pole rows (R, P), and means (19) for producing a magnetic field linking the first and second parts (11, 16) and having an even number of poles which are of alternating polarities and spaced-apart along the first and second pole rows (R, P), the magnetic field travelling along the first and second pole rows (R, P) and subtending a plurality of the poles of the first and second pole rows, the number N of salient poles (14) of the first pole row (R) subtended by the travelling magnetic field being at least four times the number n of pole pairs of the travelling magnetic field, and the number of pole pairs of the second pole row (R) subtended by the travelling magnetic field being said number N of salient poles (14) plus or minus the number n of pole pairs of the travelling magnetic field.</p> |
