| 摘要 |
PURPOSE:To reduce th torque ripple of a DC motor at the time of operating the motor by forming recesses on the surfaces of respective poles of a rotor magnet magnetized in multiple poles and equalizing a change in the magnetic flux upon rotation of the motor. CONSTITUTION:In a motor in which a magnet rotor 1 magnetized in multiple poles is allowed to confront a plurality of a coils 2-4 sequentially energized in response to the rotating angle of the rotor 1, recesses 20 are formed on the surfaces of respective poles of the rotor 1 corresponding to the energizing periods of the respective coils 2-4, and the length of the air gap of a closed magnetic path is varied from a yoke 7. In this manner, since the variation 13 in the magnetic flux produced upon rotation of the rotor is uniform at the energized part of the coils, the produced torques become constant, thereby preventing the torque ripple. |
