| 摘要 |
PROBLEM TO BE SOLVED: To suppress a variation in characteristics caused by demagnetization as well as the distortion of an induced voltage for lower noise and vibration, related to a rotor of a DC motor where a permanent magnet is disposed on its surface. SOLUTION: Related to the rotor of a DC motor in which a permanent magnet is disposed on a surface opposite to a stator, the surface opposite to the stator near the magnetic pole border of the permanent magnet is provided with a groove of such a form as contains a straight line in an axial direction, at an angleθof the circumferential width of the groove being 200°/n<θ<280°/n (n is the number of magnetic poles of the rotor). COPYRIGHT: (C)2004,JPO |
