| 摘要 |
PURPOSE:To detect the rotary position of a motor, easily and surely, by attaching a particular part to the armature coil of the motor, and detecting the part with a sensor. CONSTITUTION:For example, a flat coreless motor wherein the armature 21 connected to the external power source through the commutator 22 and the brush 23 is rotated to a definite direction by the interaction between the current in the coil and the magnetic field of the permanent magnet 24, is furnished with a coil 28a having a radius of larger than the other coils 28, and a sensor 27 for the detection of magnetic flux generated by the current in the coil is attached to the yoke 29. The strength of the signal induced in the sensor 27 (the symbol 34 is amplifier, and 35 is waveform shaping circuit) by the coils passing near the sensor by the rotation of the motor becomes especially high when the coil 28a is in front of the sensor 27. The rotary position of the motor can be detected thereby. |
