CONTROL SYSTEM FOR WIRE CUT ELECTRIC DISCHARGE MACHINING AND WIRE CUT ELECTRIC DISCHARGE MACHINE

摘要

PURPOSE:To improve the accuracy of the width of a working grove by a method wherein the working speed of the wire cut electric discharge machining is controlled by working it out from a working current, the width of the working groove and the thickness of a work piece. CONSTITUTION:A pulse voltage is impressed to a wire electrode 2 and the work piece 1 while the electric discharge current, flowing through a working clearance, is detected by a detector 9. A short-circuit detector 10 detects the voltage of the working clearance to decide a short-circuit and closes a switch 11 only upon the normal electric discharge to transmit a current detecting signal to a smoothing circuit 12. The output of the smoothing circuit 12 expresses a real working current Iw and the working speed F is controlled by working out it by a formula F=K1(Iw-K2h)/hd, wherein, (d) is the width of the working groove, (h) is the thickness of a work piece, K1, K2 are constants. The width of the working groove may be kept in constant by controlling the working speed in such a manner.