| 摘要 |
PURPOSE:To save power and to enable highly accurate position control by applying minimum necessary hold torque and switching to holding through detent torque at the stage when it is allowed. CONSTITUTION:When a CPU produces a drive pulse from its output port P0, Q1 is turned ON to turn Q5 ON and Q8 is turned ON by the drive pulse fed from P0, and thereby current flows through a coil L1 from phi1 to phi2 thus exciting the coil L1. When the CPU judges that the level has varied, a counter (c) is set to zero count. The counter (c) is incremented upon elapse of 0.1msec and checked whether the count thereof has reached to 30, and if the count has not reached to 30 input to P4 is checked and variation of level is checked. When this operation is repeated, a section where current vibrating with slightly shorter period than vibration period 3msec and with predetermined dead level is detected. Then power conduction to a motor is stopped to finished excitation of the motor and the rotor is held by means of detent torque. |
