| 摘要 |
PURPOSE:To perform the taper machining with high accuracy by a method wherein the wire electrode of an electrical discharge machine is tilted and the wire and a work piece are controlled so that the tilting angle of the wire electrode is rendered to continuously change when the wire electrode travels along a calculated passage comprising in smoothly connecting between the straight lines perpendicularly intersecting each other in the lower surface of the work piece with a plurality of circular arcs. CONSTITUTION:A straight line B2B2', which is parallel to the tangent touching a circular arc a at a point B in the upper surface of the work piece and passes through a point B2 in the lower guide corresponding to the point B, and a straight line C2C2', which is parallel to the tangent touching the circular arc a at a point C and passes through a point C2 in the lower guide corresponding to the point C, are obtained. An intersection J of the bisectors of the angles made by the straight lines B2B2' and B2C2 and by the straight lines C2C2' and B2C2 is calculated. Perpendiculars m1, m2 and m3, which are dropped from the intersection J, the point B2 and the point C2 to the straight lines B2C2, B2B2' and C2C2' respectively, are calculated in order to obtain the intersections P1 and P2 of the perpendiculars m1 and m2 and the perpendiculars m1 and m3. A desired curve e is obtained by drawing a circular arc e1 with center at the point P1 and a circular arc e2 with center at the point P2. After that, the lengths L1 and L2 of the circular arcs e1 and e2 are calculated. The relative movement of wire electrode to the work piece is controlled so that its locus in the upper surface of the work piece is the circular arc BI while its passage in the lower guide is the circular arc B2J. |
