| 摘要 |
PURPOSE:To reduce vibration and noise during rotation by forming groove sections axially at positions corresponding to 60 deg. and 120 deg. electrical angles on the outer circumferential face at the salient pole section of a rotor. CONSTITUTION:Salient polse sections 16-19 are formed at four positions crossing perpendicularly, and four field permanent magnets 20-23 are burried at positions adjoining to the salient pole sections 16-19. Furthermore, groove sections 16a, 16b are formed in the outer circumferential face of the salient pole section 16, and the grooves are formed in zigzag around the sections corresponding to 60 deg. and 120 deg. electrical angles of the salient pole section 16. The groove sections 16a, 16b function to partially reduce the flux in the air gap section between the stator 11 and the salient pole section 16 of the rotor 14. Since the flux in the air gap section is weakened, torque ripple is weakened when power is fed to the stator coil. By such arrangement, combined torque can be maintained constant. |
