Patent ID: 9515527
Filing Date: 2016-12-06
CPC Classification: H02K,Y10T

Claim Text:
1. An electric motor comprising: a rotor provided on a rotary shaft; and a stator fixed outside an outer peripheral surface of the rotor, the rotor including: a rotor core fixed to the rotary shaft so as to be rotatable together with the rotary shaft; and a plurality of permanent magnets embedded and fixed in the rotor core, wherein the permanent magnets extend in radial directions of the rotor and are spaced from each other in a circumferential direction of the rotor and each of the permanent magnets have a magnetic-pole facing portion with a flat plate shape that extends radially and a proximity portion that extends from a radially inner end portion of the magnetic-pole facing portion toward the magnetic-pole facing portion of an adjacent permanent magnet so that the proximity portion of permanent magnets adjacent to each other face each other, and each of the permanent magnets (i) is magnetized in directions normal to a surface of the permanent magnet so that poles of the same polarity face each other in the circumferential direction, (ii) has a uniform thickness and (iii) is bent from one end portion of the rotor to the other end portion of the rotor with respect to a direction of the rotary shaft of the rotor so that the permanent magnet has a triangular wave shape in which a plurality of linear portions are sequentially connected, and wherein the magnetic-pole facing portion of each of the adjacent permanent magnets is substantially longer than the proximity portion such that the magnetic-pole facing portions extend generally along a straight line to the proximity portion, the proximity portions defining a curved shaped end of each of the adjacent permanent magnets.