| 主权项 |
1. A rotor comprising:
a rotor core fixed to a rotating shaft so as to be rotatable together with the rotating shaft; and a plurality of permanent magnets embedded and fixed in the rotor core, wherein each of the permanent magnets comprises: a pair of magnetic pole-facing portions radially extending and magnetized so that poles of the same polarity face each other in a circumferential direction, a pair of magnet pieces facing each other with an interval therebetween in the circumferential direction, and having proximity portions and the magnetic pole-facing portions, the proximity portions having an arc curved plate shape and the magnetic pole-facing portions having a flat plate shape, and a protruding portion provided at a radially outer end portion of each of the pair of the magnetic pole-facing portions, the protruding portion protruding in a direction orthogonal to the magnetization direction of the magnetic pole-facing portion, and being magnetized in a direction that is the same as the magnetization direction, wherein the protruding portion is formed in a stepped shape having a length in the circumferential direction that decreases stepwise toward the radially outer end portion of each of the pair of magnetic pole-facing portions, each of the magnetic pole-facing portions and each of the proximity portions is provided in each magnetic piece, respectively, and the proximity portions extend from radially inner end portions of the magnetic pole-facing portions in such directions that the proximity portions approach each other, a magnetic resistance of each of the pair of the magnetic pole-facing portions in a magnetization direction is greater in a radially outer portion than in a radially inner portion radially inner portion, wherein connecting portions are provided in the rotor core, and each of the connecting portions connects a corresponding one of inter-magnet-piece portions of the rotor core to a core portion of the rotor core, each of the inter-magnet-piece portions being sandwiched by the pair of the magnet pieces and serving as a magnetic path for the magnet pieces, and the core portion being fitted to the rotating shaft; and wherein a plurality of hollows is formed between adjacent magnet pieces of the pair of magnet pieces in each of the inter-magnet-piece portions sandwiched by the pair of the magnet pieces. |
