METHOD FOR CONTROLLING WITHDRAWAL MOVEMENT OF COUNTERSINK ELECTRODE IN ELECTROEROSION MACHINE

To eliminate short-circuits between a countersink electrode and a workpiece during countersink erosion, when a short-circuit occurs, the countersink electrode is initially moved back by a predetermined path length ( delta ) along the previously travelled path from a first locus (PK) at which the short-circuit occurred to a second locus or intermediate point (PR) and it is established at that location whether there is still a short-circuit. If this is the case, the countersink electrode is moved in an upwardly sloping manner along a second path (R), which has a first angle ( alpha ) with respect to the working plane (AE) and has a movement component (R1) having a second angle ( beta ) with respect to a surface normal to the short-circuit or intermediate point (PK or PR). All the parameters ( alpha , beta , delta ,¦R¦) can be freely preselected and are variable during erosion.