| 摘要 |
PURPOSE:To prevent a workpiece from being rusted by providing an auxiliary power supply which applies negative electric potential to the workpiece of wire cut discharge machining. CONSTITUTION:Such a pulse voltage as to make a workpiece 2 positive is applied to a wire electrode 3 and said workpiece 2 of a wire cut discharge machining unit, and the discharge machining is performed. Further, the negative pole a nd the positive pole of an auxiliary power supply 13 are applied to the workpiece 2 and machining liquid respectively so that the workpiece 2 is maintained at negative electric potential even in case said machining is finished or interrupted. Thus the workpiece can be prevented from being rusted at finish or interruption of the machining. |
