Patent ID: 7888617
Filing Date: 2011-02-15
Classification: B23H

Abstract:
1. A controller for controlling multi-pass machining by a wire cut electrical discharge machine, the controller comprising: machining program storage means for storing a machining program; machining program analyzing means for analyzing the machining program stored in said machining program storage means; offset storage means for storing a wire offset set for each machining pass; machining route creating means for creating a machining route on the basis of the result of analysis by said machining program analyzing means and the offset stored in said offset storage means; machining route correcting means for correcting the machining route at a reentrant angular corner formed by two straight motion blocks in said machining route, the straight motion blocks being not parallel to each other; reference machining pass setting means for setting a reference machining pass to determine a machining pass for initiating said machining route correction by said machining route correcting means; and offset difference calculating means for calculating a difference between the offset for said reference machining pass and the offset for a machining pass one or more passes after the reference machining pass; wherein said machining route correcting means corrects the machining route created by said machining route creating means by removing, from the two straight motion blocks forming the reentrant angular corner, sections adjacent to the vertex of the reentrant angular corner and inserting, in place of the removed sections, a circular arc motion block having a radius of curvature determined on the basis of the result of calculation by said offset difference calculating means.