| 摘要 |
PURPOSE:To increase machining speed and accuracy for preventing occurence of electric erosion in a corner area by providing a wire cut electric discharge machine with intermittent positive voltage applying means and intermittent negative voltage applying means and actuating these means alternately. CONSTITUTION:Intermittent positive voltage applying means 3 includes a power supply 31, a current restricting resistance 32, an on-off controller 33 such as power transistor, a variable frequency pulse oscillator 34 and others. Intermittent negative voltage applying means 4 includes a power supply 41, a current restricting resistance 42, an on-off controller 43 such as power transistor, a variable frequency pulse oscillator 44 and others. When a workpiece 1 is machined by a wire electrode 2, only the intermittent positive voltage applying means 3 is actuated in a linear machining area to execute high speed electric discharge machining. In a corner area, the intermittent positive voltage applying means 3 and the intermittent negative voltage applying means 4 are alternately actuated for machining, which causes some reduction of machining speed but permits high machining accuracy without occurence of electric erosion. |
