Patent ID: 6747238
Filing Date: 2004-06-08
Classification: B23H

Abstract:
An apparatus for electrodischarge machining for machining a workpiece by moving a tool electrode toward the workpiece in the vertical direction while causing electric discharge through an extremely small gap between the workpiece and the tool electrode, comprising:a T-shaped quill moving in the vertical direction, having a rectangular cubic member formed in an upper portion and a square column formed in a lower portion, said cubic member having three coaxial through holes, two of said through holes located at two sides with one of them with a T-shaped cross-section located between said two through holes, said square column having its upper end fixed with a lower end of said cubic member, a level fixing plate provided in an intermediate point in said square column to define a hole in an upper portion of said straight cylinder, said upper hole having the same cross-section as that of the T-shaped hole of said cubic member and communicating with the same hole; an electrode mounting device provided under said square column of said T-shaped quill in the same axis of said cubic member and said square column; two rectangular posts fitting in said two rectangular through holes in the same axis direction as said T-shaped quill and having an upper and a lower end connected to said frame; at least two linear motors respectively consisting of a moving member and a stator, said moving member positioned in said two through holes of said cube member in a symmetrical location with said T-shaped through hole as a center, said stators respectively positioned to face said moving members; and, a counter balance device for balancing gravitational force acting on said T-shaped quill and said electrode-mounting device.