Spark erosion machine where electrode has orbital motion - to produce taper in dies for blanking sheet metal

摘要

The device controls electrode movement on a spark erosion machine in making a cavity with a progressively increasing transverse dimension, i.e. at 990 degrees to the direction of electrode feed. The electrode is mounted on a cross-slide underneath a ball joint at the bottom end of a pendulum rod located in a guide bush held by a diaphragm in a guide plate. The top end of the pendulum rod is a ball located in a ball seat mounted on a rotating eccentric so the electrode is driven in a circular orbit of increasing magnitude as it is fed through the workpiece. It is used e.g. in the prodn. of cavities in dies used for blanking sheet metal, where the cavity has a draw taper so the scrap blanked part drops through the die cavity.