Device for guiding seams of bags

Claim 1

A machine for sewing closed the open mouth of a bag by means of a conventional bag sewing machine having a frame presenting laterally spaced leg portions joined at their upper ends to define an archway through which the mouth of a bag is passed during the sewing operation, one leg presenting a vertical surface and the other leg carrying a pressure foot which presses the bag mouth flatwise against said vertical surface, the improvement which comprises: a frame and conveying means on said frame for travelling a bag along a given path; a subframe mounted on said frame above said conveying means, said sewing machine being mounted on said subframe to allow the open mouth of a bag to pass through said archway as the bag is moved by said conveying means; a first worm roller rotatably mounted on said subframe and extending horizontally from a point spaced from said sewing machine in the upstream direction of the travel of said conveying means and extending therefrom into said archway above said pressure foot and closely adjacent said vertical surface; a second worm roller rotatably mounted on said subframe and extending horizontally into said archway closely adjacent said vertical surface and in substantially vertical registry with and above said first roller to define a nip therewith which lies in a substantially horizontal plane; means for driving said rollers in opposite directions to feed a bag mouth in the direction of bag travel while pulling the bag mouth over said first roller in said substantially horizontal plane with the bag mouth portion immediately below said first roller substantially flatwise against said vertical surface and between it and said pressure foot; said second roller commencing at a point closer to said sewing machine than said point at which said first roller commences whereby an upstream end portion of said first roller projects beyond said second roller.