| 摘要 |
PURPOSE:To obtain the position detecting signals in high quality without the effect of an intense magnetic field by providing the first - third sections having the different physical properties at the outer surface of a rotor, which is rotated in synchronization with a motor, as the width of the specified angle, and performing the energization control of an armature coil at the phases of the corresponding first - third position detecting signals. CONSTITUTION:The center of a rotary disk 15 is fixed to the right end of a rotary shaft 5. The disk is rotated in synchronization with a rotor. Protruding parts 15a, 15b and 15c are provided at the rotating outer surface of the rotary disk 15, and the width is set at 120 degrees. Protruding parts 16a, 16b and 16c of a plastic disk 16 are provided at the neighboring parts of the protruding parts 15a, 15b and 15c. The surfaces of the protruding parts 16a, 16b and 16c are retreated from the protruding parts 15a, 15b and 15c by the specified length. The width of the protruding parts 16a, 16b and 16c is also set at 120 degrees. magnetic poles having the width of 120 degrees are arranged at the outer surface of the plastic disk 16. The position detecting signals are obtained and the energization control is performed. Thus, the position detecting signals in high quality are obtained without the effect of the intense magnetic field. |
