| 摘要 |
PURPOSE:To shorten the time which is required to switch the rotating direction of a motor by switching by torque control means to large torque when switching the rotating direction of the motor. CONSTITUTION:When the rotating direction of a motor 1 is switched, the output from a band pass filter 11 is inputted to a control circuit 12 in the state of constant speed rotation so far, but when a command from a rotating direction instruction circuit 9 is inputted in this state, a switch circuit 13 is closed. When the circuit 13 is closed, resistors 8, 14 are connected in parallel with each other. Since the synthetic resistance is reduced as compared with value of resistor 8, the maximum torque of a motor 1 increases. In this manner, the rising time of the motor 1 is shortened, and the switching time of the motor in the rotating direction can be performed in a short time. |
