Web-handling apparatus including guide roller assembly with resiliently deformable outer layer

Abstract

A web-handling apparatus includes at least one guide roller assembly having an inner, cylindrical core, and an outer layer affixed thereto. Notably, the outer layer of the roller assembly comprises resiliently deformable material, with polyurethane foam having proven to be particularly suitable for this application. By this arrangement irregularities in an associated film web, such as in the form of side gussets and / or zipper fastener assemblies, are readily guided by the roller assembly while avoiding wrinkling or other stress of the associated film web.

Description

TECHNICAL FIELD[0001]The present invention relates generally to apparatus for handling film webs, such as in connection with manufacture of bags or pouches, and more particularly to a web-handling apparatus including a guide roller assembly which includes an outer layer of resiliently deformable material to accommodate irregularities in the associated film web, thereby promoting efficient and precise web handling.BACKGROUND OF THE INVENTION[0002]Apparatus are known for handling film webs, typically polymeric material, in connection with the manufacture of bags, pouches, and like articles. During manufacture of such articles, it is frequently necessary for folds and / or gussets to be formed in the film web, which can thereby result in certain portions of the web, along the longitudinal direction thereof, being thicker than adjacent portions.[0003]Other irregularities in the thickness of a film web can result from the placement of zipper-like fastener assemblies on the web, typically i...

AI Technical Summary

Benefits of technology

[0007]The present invention is directed to a web-handling apparatus comprising at least one guide roller assembly about which an associated film web is guided. In accordance with the preferred form of the present invention, the guide roller assembly includes an outer layer of resiliently deformable material, which in a presently preferred embodiment, comprises polyurethane foam. By virtue of the resiliently deformable nature of the outer roller material, irregularities in the film thickness are readily accommodated, while avoiding undesired wrinkling or the like in the film web. Efficient and precise web handling is thus facilitated, with the construction providing a desirable combination of support and “forgiveness” to promote wrinkle-free web-handling.

Problems solved by technology

During manufacture of such articles, it is frequently necessary for folds and / or gussets to be formed in the film web, which can thereby result in certain portions of the web, along the longitudinal direction thereof, being thicker than adjacent portions.

Other irregularities in the thickness of a film web can result from the placement of zipper-like fastener assemblies on the web, typically in the longitudinal direction thereof.

The irregularities in film thickness which typically result during manufacture of bags and the like can be problematic, in that wrinkles can undesirably form in the gusset, or at a portion of the film web where the size and position of the gusset changes.

Such problems typically occur when an already gusseted film web wraps around a roller for more than about 45 degrees of the circumference.

However, both of these methods entails certain drawbacks.

Relatively large rollers can be quite expensive, particularly when compared to a typical roller having a 4-inch diameter.

Additionally, large rollers undesirably add significant rotational inertia to the web-handling apparatus.

Fluted rollers are also more expensive than typical 4-inch rollers, and they may also add more rotational inertia to the apparatus.

Additionally, fluted rollers can undesirably mark or crease the film web, and experience has shown that fluted rollers are not always effective for handling some types of film material.

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