| 摘要 |
PURPOSE:To enable a motor to be controlled at high precision and in a wide range, by switching frequency-dividing signal for frequency-dividing the one side signal of the two-phase signals of an encoder, and signal for shifting the phase of the frequency-dividing signal by 90 degrees, according to the rotational direction of the motor. CONSTITUTION:Signal A1 among the two-phase signals A1, B1 of an encoder 2 is frequency-divided by frequency dividers 3, 4 to obtain frequency-dividing signal A2. Besides, by a shift resistor 5, the signal B2 of phase delayed by 90 degrees from that of the frequency-dividing signal A2 is obtained. In the meantime, by rise detectors 7, 8, a fall detector 9, and a direction detector 11, the rotational direction of a motor 1 is detected. By a switch 6, the signals A2, B2 are switched according to the rotational direction of the motor, and output is generated. By a control circuit 13, the motor 1 is controlled according to the phase comparing result of signal from the switch 6 and external input signal 12. |
