| 摘要 |
In a wire electric discharge machining apparatus, this invention relates to a method of connecting automatically a broken wire electrode (4) and then returning it to a breakage position when the wire electrode (4) is broken during machining. When wire guides (30), (32) and the broken wire electrode (4) are returned from the breakage point to a machining start point, any obstacles such as sludges adhering to the machining portion of a workpiece (1) and to the wire guides (30), (32) are removed by jetting a washing agent (80) so as to remove any obstacles to automatic wiring and to prevent breakage of the wire electrode (4) during the machining restoration operation. The conditions during restoration such as the shape of a machined path, contact state between the wire electrode (4) and the workpiece (1) are detected and a restoration speed for returning the connected wire electrode (4) to the breakage point is set to an optimum one in accordance with the detected conditions. Accordingly, the wire electrode (4) can be returned rapidly to the breakage point without causing its re-breakage. |
