Apparatus and method for folding film edges
Pre-stretched films may be used to increase the rate at which loads can be wrapped and to minimize the exertion required when using traditional handheld film. However, the edges of pre-stretched films are easily damaged, which may result in tearing or failure of the film during use. The present disclosure describes devices, systems, and methods for folding the edges of the film, resulting in a film that is less susceptible to damage and easier to use.
1. An apparatus for producing folded edges in a film in-process, the apparatus comprising:
a first idler roll;
a second idler roll separated from the first idler roll by a first distance; and
a plurality of folding guides that are positioned between the first idler roll and the second idler roll, wherein each folding guide separates adjacent sections of film and induces two folds by causing an edge of each section of film to turn under 180° and spontaneously cling to a bottom surface of the film as the film travels from the folding guides to the second idler roll.
2. The apparatus according to claim 1 , wherein the folding guide is a folding rod.
3. The apparatus according to claim 2 , wherein the folding rod varies from ⅜ inch to 1 inch in diameter.
4. The apparatus according to claim 3 , wherein the folding rod is approximately 11/16 inch in diameter.
5. The apparatus according to claim 1 , wherein the folding guide is positioned between the first idler roll and the second idler roll at a guide distance and a guide angle.
6. The apparatus according to claim 5 , wherein the guide distance is approximately ⅔ of the first distance.
7. The apparatus according to claim 5 , wherein the guide angle varies from 20° to 90°.
8. The apparatus according to claim 1 , wherein the film passes through a nip roll assembly after the second idler roll.
9. The apparatus according to claim 1 , wherein the folding guide is comprised of a material with sufficient modulus to be able to maintain rigidity.
10. The apparatus according to claim 1 , wherein the folding guide is comprised of a material with a coefficient of friction that introduces edge folds.
11. The apparatus according to claim 1 , wherein the folding guide is comprised of a material selected from a group consisting of steel, aluminum, and nylon.
12. An apparatus for producing folded edges in a film in-process, the apparatus comprising:
a first idler roll;
a second idler roll separated from the first idler roll by a first distance; and
means for separating adjacent sections of film and inducing two folds by causing an edge of each section of film to turn under 180° and spontaneously cling to a bottom surface of the film, said means positioned between the first idler roll and the second idler roll.
13. The apparatus according to claim 12 , wherein said means is a folding guide comprised of a material having a coefficient of friction that causes an edge of the film to turn under 180° and spontaneously cling to a bottom surface of the film.
14. The apparatus according to claim 12 , wherein the folding guide is positioned between the first idler roll and the second idler roll at a guide distance and a guide angle.
15. The apparatus according to claim 14 , wherein the guide distance is approximately ⅔ of the first distance.
16. The apparatus according to claim 14 , wherein the guide angle varies from 20° to 90°.