Patent ID: 6326577
Filing Date: 2001-12-04
Classification: B23H

Abstract:
A wire cut electrical discharge processing device for processing a workpiece by generating a discharge between a wire electrode and a work piece, said wire cut electrical discharge processing device having a wire transport path and comprising:a wire take up device for pulling the wire electrode through the wire transport path;a servo motor for applying tension to the wire electrode;an NC device for generating a signal indicative of a set value of wire tension;a tension detector for detecting the tension applied to the wire electrode and generating a signal indicative of the detected value;a tension control device for controlling the rotational speed of the servo motor on the basis of the signal indicative of a set value of wire tension and the signal indicative of the detected value of wire tension; andwherein the tension control device includes at least two notch filters each of which suppresses components of different unnecessary frequencies in the signal indicative of the detected value of wire tension.