JPS6411737A - Electric discharge machining method - Google Patents

Abstract

PURPOSE:To prevent an intermediate swell in a workpiece by moving a shaft, vertical with a swivel plane, in accordance with a change of voltage between an electrode and the workpiece and changing a swivel radius being based on a value multiplying a vertical moving amount by a constant depending on a depth of cut. CONSTITUTION:In order to hold voltage between an electrode and a workpiece to a fixed value, a swivel radius R is changed in accordance with a depth of cut and a moving amount in a servo shaft vertical with a swivel plane, and the workpiece equalizes its machining condition of the bottom surface direction to that of the side surface direction. That is, the servo shaft is moved by the amount of (a) mum for a change v(V) of the voltage. When the change v(V) of the voltage is generated while the electrode is in peripheral turning motion by the swivel radius R and a speed (w), the swivel radius R is changed by ka. Here the symbol k is a function of depth of cut. By the method thus obtained, enabling the stable swivel machining, peripherally turning on the swivel plane in a fixed speed, to be realized from a roughing condition to a finishing condition, an intermediate swell of the workpiece can be prevented.