Numerically controlled wire-cutting electric discharge machine

Claim 1

A numerically controlled wire-cutting electric discharge machine using a wire electrode comprising: a numerical control apparatus sending out, at least a first, a second and a third command signal for at least three control axes; a workpiece supporting means for supporting a workpiece; a first motor means which moves said workpiece in a direction along an axis in a plane which is perpendicular to a predetermined axis; a second motor means which moves said workpiece in another direction along another axis in said plane; a pair of V type slot guides including a first guide and a second guide, said first and second guides being arranged opposed to each other with respect to said workpiece so as to stretch, in a direction which coincides with said predetermined axis, said wire electrode which passes through said workpiece; a rotatable supporting member which supports said second guide and which can rotate around said predetermined axis; an offset means which offsets said second guide in a predetermined direction in said plane which is perpendicular with said predetermined axis, so that the position of said wire electrode at said first guide coincides with said predetermined axis and the position of said wire electrode at said second guide is offset a predetermined amount from said predetermined axis; a third motor means coupled to said rotatable supporting means for rotating said second guide around said predetermined axis; said numerical control apparatus supplies first and second signals to said first and second motor means, respectively, and said wire electrode moves relatively with respect to said workpiece in the plane which is perpendicular to said predetermined axis, and said numerical apparatus supplies said third signal to said third motor means and rotates said rotatable supporting means so that the surface which is determined by said predetermined axis and said wire electrode which is offset is perpendicular with respect to a relative movement between said wire electrode and said workpiece, and wherein said second guide is mounted on said rotatable supporting member in such a manner that the center line of the V type slot of said second guide is perpendicular to the relative motion between said wire electrode and said workpiece.