Patent ID: 7056417

Claim:
An apparatus for welding first and second extruded plastic zipper strips to each other, said first zipper strip comprising a first zipper flange and a first closure profile, and said second zipper strip comprising a second zipper flange and a second closure profile that is interlockable with said first closure profile, said apparatus comprising first and second tools, at least one of said first and second tools being movable relative to the other, said first tool comprising a first body and a first plurality of surface features confronting said second tool, and said second tool comprises a second body and a second plurality of surface features confronting said first tool when said first and second tools are brought into a mutually confronting relationship, wherein said first and second pluralities of surface features, when heated and placed on opposing sides of mutually interlocked sections of said first and second zipper strips, weld said first and second zipper flanges together in a first zone and weld said first and second closure profiles together in a second zone, said second zone being wider than said first zone, the widths of said first and second zones being measured along the length direction of said first and second zipper strips.