摘要 |
<p>PROBLEM TO BE SOLVED: To reduce cost by reducing the quantity of heavy rare earth elements in a permanent magnet, in a motor comprising a rotor in which the permanent magnet is embedded.SOLUTION: A permanent magnet (5) of a rotor (3) is divided into a stronger-side central portion (5a) and a weaker-side end portion (5b) in accordance with a strength of opposing magnetic fields that act on the permanent magnet (5) by electrifying a coil (2b) of a stator (2). A ferrite magnet is used for the end portion (5b) and a rare-earth magnet is used for the central portion (5a).</p> |