| 摘要 |
<p>This invention relates to a method of preparing NC data for coreless machining in wire cut discharge machining using an automatic programming apparatus. A programming apparatus which reads the profile (C1) of a machining area (A1), a wire connecting position (PO) and a maximum cut-in quantity from a PERT program prepares NC data for moving a wire from the wire connecting position (PO) to a machining area center position (P1) (S1) while effecting discharge machining, determines a spiral tool orbit consisting of circular orbits (PS1 ∩ PS3) each having a shape similar to a figure expressing the profile of the machining area and spaced apart mutually by a maximum cut-in distance and linear orbits connecting the adjacent circular orbits with one another and prepares NC data for making rough machining along the linear orbits and circular orbits inside a finish machining area inner peripheral curve (C2) (S2). When the NC data for making final rough machining along the inner peripheral curve is produced (S3), the cut-in distance from the circular orbit (C3) adjacent to the inner peripheral curve is limited to the distance between them. Finally, NC data for making finish machining along finish machining orbits (C4, C5, C1) outside the inner peripheral curve determined on the basis of a finish margin and the number of finishes in the PERT program is prepared (S4).</p> |
