| 摘要 |
PROBLEM TO BE SOLVED: To reduce small-angle errors, despite constant current controlling method. SOLUTION: This equipment is constituted of a constant-current control circuit 10 for controlling the current input from a power supply, not shown, to be constant, a bipolar method drive circuit 20 wherein each arm is constituted of a pair of switching elements FET 21A, 21AA-21E, 21EE for each phase and each phase current of a five-phase stepping motor, not shown, is generated by turning these switching elements on and off, and a signal circuit section 30 which generates pulse width modulation signals A, AA,...E, EE for controlling the on/offs of the switching elements. Based on the pulse width modulation signals A, AA,...E, EE, the switching elements FET 21A, 21AA-21E, 21EE of the drive circuit 20 are turned on/off and sinusoidal wave phase currents are generated. The ratios of the magnitudes of the phase currents are changing all the time, but the sum of the phase currents is kept the same at all times. |
