Patent ID: 6725751
Filing Date: 2004-04-27
Classification: B21D,Y10T

Abstract:
A rotary punching apparatus for punching elongate openings in a moving web workpiece the elongate openings having a predetermined length along the longitudinal axis of the web and comprising;two die assemblies located on opposite sides of the path of the web workpiece, and power means for rotating the assemblies; a first die mounted on one said assembly of said assemblies, and movement means for moving said first die generally outwardly relative to said one assembly so as to punch a first die opening through said web; a second die on said one assembly adjacent to said leading die, said second die being located to engage and punch the web whereby to punch a continuation of said first die opening in said web, thereby defining a continuous opening, and; a third die cooperating with said first and said second dies, whereby to pierce said web and further define and expand said continuous opening.