Patent ID: 8420973
Filing Date: 2013-04-16
Classification: B23H

Abstract:
1. A power-supply control device that controls discharge pulses supplied to an electrical discharge machining apparatus that machines a workpiece by generating pulse discharge in a machining gap between a machining electrode and the workpiece, the power-supply control device comprising: a voltage level detecting unit that detects a voltage level of discharge voltage at the machining gap; a no-load time detecting unit that detects delay time of discharge of the discharge voltage; a voltage level comparing unit that compares the detected voltage level with a reference voltage level; a pulse control unit that controls pulse off time, the pulse off time being an interval between discharge pulses supplied to the electric discharge machining apparatus, based on a comparison result obtained by the voltage level comparing unit and the detected delay time of discharge of the discharge voltage; a machining-condition control unit that changes a machining condition to increase machining efficiency in stable machining based on output of the pulse control unit; an average off-time calculating unit that calculates average pulse off time based on output of the pulse control unit; and a machining stability judging unit that judges a machining state using the average pulse off time as an index, wherein the machining-condition control unit changes the machining condition based on a judgment result obtained by the machining stability judging unit.