摘要 |
A permanent magnet for use in an electro-dynamic machine. The permanent magnet has a longitudinal axis and a plurality of ferromagnetic ring members arranged in a co-axial stack. Each ring member has a plurality of arcuate magnetic poles arranged around a circumference of the ring members. The ring members are magnetized such that a pole boundary between each pair of magnetic poles is skewed at an angle Φ, where Φ is non-parallel to the longitudinal axis. |