Device, standard blanks and standardized electrodes for electro-discharge milling

A device for EDM die sinking and milling machines for turning and touching up a tool-electrode during machining of a workpiece and without having to dismount the tool-electrode from a machining head of an EDM machine, the machining head being movable vertically and has a spindle which rotates about an axis, said device comprising:

• a tool-holder mounted on the machining head, said tool-holder having means for fastening the tool-electrode when turning and touching up the tool-electrode;
• a working tank in which is mounted the workpiece;
• an auxiliary tool holder mounted on the working tank and an auxiliary tool mounted in the auxiliary tool holder, the auxiliary tool is shaped to accurately machine and touch up an active tip of the tool-electrode;
• a numerical control unit for accurately locating and positioning the active tip of the tool-electrode for touching up by said auxiliary tool and for resumption of EDM machining of the workpiece after touching up by said auxiliary tool;
• and
• a sensor mounted to said auxiliary tool holder, said numerical control unit responding to an electrical contact between the tool-electrode and said sensor to displace the tool-electrode to a position at which it is machined by said auxiliary tool.