Method and apparatus for adjusting the gap in an electric discharge machine

摘要

Disclosed is an electric discharge machining method in which the electric discharge working gap between an electrode and a work piece to be machined is automatically adjusted. To detect the condition of the discharge working gap, a low voltage pulse is applied each time a plurality of high voltage pulse for electric discharge machining are applied for a predetermined time. The working current resulting from the application of each low voltage pulse is detected to control the feeding of the electrode and thereby to automatically adjust the discharge working gap to a predetermined value.