Wire electric discharge machine having function for counting number of discharge times

摘要

In a wire electric discharge machine, a permissible discharge frequency is calculated on the basis of an average discharge frequency per unit time which is estimated on the basis of a target inter-electrode voltage or a detected average inter-electrode voltage and a discharge period. The number of times a discharge is actually induced between a wire electrode and a workpiece every unit time is counted and the application of a pulse-shaped voltage is ceased for a residual time of the unit time by a control device when the discharge frequency exceeds the permissible discharge frequency.