Patent ID: 8395069

Claim:
A method for controlling an electric discharge machining process, wherein a tool electrode is moved relatively to a workpiece with a working gap distance, wherein the process comprises a current and at least one previous erosion cycle, the current and the at least one previous erosion cycle each being divided into predetermined time intervals each comprising at least one discharge pulse, and wherein the current erosion cycle and the at least one previous erosion cycle are separated by a process pause cycle that is operable to restore a working gap condition, the working gap condition of the current erosion cycle and the previous erosion cycle being substantially similar, the method comprising the steps of: measuring a value of an indicative process parameter within the time interval of the previous erosion cycle, the indicative process parameter being indicative of the working gap distance; determining a deviation value based on the measured value and a desired value of the indicative process parameter of the time interval of the previous erosion cycle; and in the current erosion cycle, controlling the relative movement of the tool electrode in a current erosion direction within the time interval of the current erosion cycle based on the deviation value determined for the time interval of the previous erosion cycle and at least one instantaneous process parameter that is indicative of an instantaneous process condition.