Hotseal jaws and cutoff knife assembly for processing thermoplastic film bag making material

Claim 1

A hotseal jaw and cutoff knife assembly for cutting individual bags from a continuous length and simultaneously seaming the edges of adjacent bags of a thermoplastic film having a pressure reclosable rib and groove zipper extending across the top of the bags, comprising in combination: complementary first and second opposed jaws extending laterally of continuous longitudinally extending multilayered bag material having a continuous longitudinally extending zipper thereon and said film bag material being fed between the jaws so that the jaws can be brought together at spaced intervals along the bag material to form side seams on adjacent bags and sever the bags intermediate said seams; the first jaw having a planar pressure pad of a resilient material and having a central opening extending parallel to the jaw; a cutter knife reciprocal in said opening to move toward the second jaw to cut the material held between the jaws; the second jaw having a roughened rigid planar face parallel to the face of the first jaw to firmly lock slippery film material therebetween; heater means for heating the second jaw in its entirety; and a lateral extending slot in the second jaw aligned with the slot in the first jaw having a strip of heat resistant rubber therein providing an anvil against which the knife moves for cutting the material as the jaws clamp and seal the layers of material to form side seams for adjacent bags separated by said knife; said face pad and said roughened face accommodating and holding the thickness of said zipper preventing leaking between the material layers sealed together at the zipper.