Patent ID: 9077224
Filing Date: 2015-07-07
Classification: H02K

Abstract:
1. A rotor core comprising: a plurality of magnet openings formed in juxtaposition with each other in a circumferential direction and in which permanent magnets are inserted; and cavity portions, each being formed relative to an area sandwiched between two magnet openings, out of the magnet openings, in which permanent magnets that are mutually adjacent and that have magnetic pole directions relative to a radial direction opposite to each other are inserted, wherein the magnet openings include a pair of magnet openings disposed such that a space therebetween widens toward an outer peripheral side and in which two of the permanent magnets having a magnetic pole direction relative to a radial direction identical to each other are inserted; each pair of the magnet openings has a shape that connects together a first opening portion formed along a profile of the corresponding permanent magnet and a second opening portion that forms, when the permanent magnet is inserted in the first opening portion, an air gap relative to the permanent magnet; the second opening portions are formed near positions at which the first opening portions are closest to each other; and the second opening portion has a shape that represents part of a side surface on the outer peripheral side of the first opening portion extended toward the outer peripheral side, the shape being finned such that a distribution of a thickness thereof with reference to the side surface of the first opening portion is offset toward the other magnet opening.