| 摘要 |
PURPOSE:To improve a torque ripple by providing an auxiliary pole having a reverse polarity to the main pole at the position of approx. + or -45 deg. of an electric angle from a boundary of detecting main poles near the opposing portions of a magneto-electric converter of a rotor. CONSTITUTION:A rotor 2 of a 3-phase brushless motor is produced by alternately magnetizing, for example, 8 N-poles and S-poles at a disc of a magnetic material as main poles 2a. Auxiliary poles 2b having reverse polarity to the pole 2a are magnetized at the positions of approx. + or -45 deg. of an electric angle from a boundary of the N-poles and S-poles of the outer periphery of the pole 2a. The poles 2b pass over a magneto-electric converter of a stator to decide a drive current by the composite signal of the converter to rotatably drive a motor. Thus, when the rotor 2 is rotated, the output signal waveforms of the converter is not saturated but becomes an abrupt waveform. |
