Permanent magnet-embedded type rotary electric machine with rotor having slots and rotor surface grooves
US10396609B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 12, 2014 |
| Grant date | Aug 27, 2019 |
| Priority date | — |
| Expiry date | Dec 28, 2034 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02K1/276
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
Magnetic flux short-circuit preventing slits extend from opposite ends of two permanent magnets in an outer circumferential surface of a rotor toward a center of a magnetic pole. Grooves formed in the outer circumferential surface can be located at a distance from each other symmetrically with respect to the center of the magnetic pole and at a distance from a groove of an adjacent magnetic pole in the outer circumferential surface. Relations are established as θf=n×τs and θs=n×τs where τs designates a pitch of stator winding slots, which pitch is converted into an angle around a rotation center, θf designates an angle between the magnetic flux short-circuit preventing slits, θs designates an angle between the grooves, and n designates a predetermined integer. Thereby, a permanent magnet-embedded type rotary electric machine in which the influence of a manufacturing error can be minimized so that cogging torque can be reduced stably.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.