| 摘要 |
<p>A wire electric-discharge machining device comprising a dc power supply (17), and a machining power feeding means (16) having switching means (19a, 19b, 19c, 19d) for switching the output voltage of the dc power supply (17), the machining power feeding means (16) feeding electric-discharge energy across a wire electrode (1a) and a workpiece (2), the wire electrode (1a) and the workpiece (2) being relatively moved by a positioning means to thereby machine the workpiece (2), wherein the device is provided with a control means (20) which, during machining operation in the air, on-off controls the switching means (19a, 19b, 19c, 19d) to provide voltages of reversed polarities such that the polarity of the wire electrode (1a) is plus and the polarity of the workpiece (2) is minus. It is possible to make the surface roughness of the workpiece (2) smoother.</p> |
