Machining process by electro-erosion

Claim 1

A PROCESS OF MACHINING BY ELECTRO-EROSION, CONSISTING IN REMOVING MATERIAL FROM AN ELECTRICALLY CONDUCTIVE WORKPIECE, WHICH MATERIAL IS GENERALLY DIFFICULT TO MACHINE, SUCH AS TUNGSTEN CARBIDE, BY CAUSING SPARKS TO EXCPLODE BETWEEN SAID WORKPIECE AND AN ELECTRODE, SAID ELECTRODE BEING IN THE FORM OF A BODY OF REVOLUTION MOUNTED ON A SUPPORT IN SUCH A MANNER AS TO BE CAPABLE OF TURNING ABOUT ITS AXIS AND CAUSING A RELATIVE DISPLACEMENT BETWEEN SAID SUPPORT OF SAID LELEVTRODE AND SAID WORKPIECE, CAUSING SAID ELECTRODE TO TURN IN SUCH A MANNER THAT, ON THE ONE HAND, EACH PORTION OF SAID ELECTRODE WHICH HAS BEEN BROUGHT OPPOSITE A PART OF SAID WORKPIECE, CANNOT RETURN A SECOND TIME INTO SAID MACHINING POSITION WITH SAID WORKPIECE, WHILST PERIPHERAL DISPLACEMENT OF EACH POINT OF THE ACTIVE PORTION OF SAID ELECTRODE RELATIVELY TO A REFERENCE SYSTEM CONNECTED TO SAID SUPPORT OF SAID ELECTRODE, IS AT LEAST EQUAL TO THE DISPLACEMENT OF THE SUPPORT OF THE ELECTRODE RELATIVELY TO SAID WORKPIECE MULTIPLIED BY THE COEFFICIENT OF WEAR OF SAID ELECTRODE RELATIVELY TO SAID WORKPIECE.