Patent ID: 6208150
Filing Date: 2001-03-27
Classification: B23H

Abstract:
An electrical discharge state detecting device for an electrical discharge machine, comprising:high-frequency component detecting means for detecting a high-frequency component superimposed on one of an electrical discharge voltage and an electrical discharge current at a machining clearance between an electrode and a workpiece;rectifying means for outputting a rectified component obtained by rectifying said high-frequency component detected by said high-frequency component detecting means;first integrating means for integrating, over time, a magnitude of said rectified component outputted from said rectifying means;reference voltage output means for outputting a reference voltage;second integrating means for integrating, over time, a magnitude of said reference voltage outputted from said reference voltage output means; integrating stopping means for stopping an integration in said first integrating means and said second integrating means only for a predetermined time on the basis of an operation of an internal switching element for use in current controlling of a machining power source;control means for controlling starting and ending of integrations in said first integrating means and said second integrating means; andcomparing means for comparing an integrated value obtained by said first integrating means with an integrated value obtained by said second integrating means.