摘要 |
<p>A wire electric discharge machine capable of detecting a contact and non-contact of an electrode pin to a wire electrode. The wire electric discharge machine has a plurality of machining power sources with respective power supply lines to be selected according to machining conditions, one polarity of each set of the power supply lines is electrically connected to a wire electrode through an electrode pin, and the other polarity of each set of the power supply lines is electrically connected to a workpiece. The wire electric discharge machine comprises an air cylinder for attachment/detachment of the electrode pin to/from the wire electrode, a short-circuit detection circuit for detecting a short circuit between the wire electrode and the workpiece, with one polarity electrically connected to the electrode pin, and the other polarity electrically connected to the workpiece, and a first relay for making the wire electrode and the workpiece have the same potential, and a controller for determining a contact/non-contact between the wire electrode and the electrode pin using the short-circuit detection circuit and the first relay.</p> |