| 摘要 |
PURPOSE: To inexpensively realize the brake of a motor in a space conserving manner by connecting a regenerative resistor to the input terminal of a motor when the abnormality of a power supply is detected by a power supply abnormality detection means at the time of the operation of a wire saw. CONSTITUTION: When no voltage is outputted from a power supply 100 by the abnormality of the power supply such as power failure, that is, no power is supplied to a drive motor 104 or an energency stop command is issued in order to prevent danger, the current of a relay coil 114 is cut off and the relay contacts 106A, 106B, 108A, 108B are changed over. By this constitution, the current loop of the drive motor 104 and a resistor 109 is formed and the regenerative current 109 generated from the rotating drive motor 104 flows toward the resistor 109 and the inertial energy of the drive motor 104 is consumed. Therefore, the rotation of the drive motor 104 is stopped instantly. |
