Plate positioning and feeding system for a punch

摘要

A pair of numerically controlled feed devices are successively operated, with the second feed device taking over from the first feed device when two or more punching steps have been performed. A trailing row of punching tools performs the first punching step with respect to a fresh plate at the same time when a leading row of tools performs the last punching step with respect to the preceding plate. There are provided sensors to determine plate length and/or angularity of the plate edges in order to enable a numerical control to compute correction data for correcting the feeding of the plate whereby punching through the trailing and leading edges of the plates is avoided.