Folder for polyfilm

Abstract

A packing machine having a film former for converting a flat, unfolded web of thermoplastic film material into a relatively flat rectangular tube with one major surface of the flat tube having an inwardly turned edge and the other major surface of the flat tube overlapping the turned-in edge. In one embodiment, the former itself comprises a single piece of rigid sheet material which has a generally rectangular portion with an isosceles right triangle integrally formed thereon, the two legs of that triangle being aligned, respectively, with an end edge and an adjacent side edge of the rectangular piece. The sheet material is then folded over or otherwise formed such that the end edge and its extension, i.e., one leg of the isosceles triangle, are parallel to the adjacent side edge with the plane of the folded portion being generally parallel to the plane of the rectangular portion. The film former has a further notch formed inwardly from the adjacent edge and disposed in the notch is a further folded triangular segment. As the web of film is routed over and through the film former, the flat rectangular tube described above is generated on a continuous basis and the product being packaged is simultaneously fed through the former and into the flat tube as it is generated. A side seal is then created in the overlapping area and, subsequently, transversely extending end seals are formed to totally encapsulate the product while severing the web.