Apparatus and method for winding film onto a film roll
An issue with conventional stretch films is that the edges of the film can be easily damaged, which may result in tearing or failure of the film during use. Folding the film edges may reduce such damage but yields uneven rolls of film that are difficult to unwind. The present disclosure describes in-process devices, systems, and methods for oscillating the film to prevent stacking of the folded edges as the film is wound onto a film roll. The present disclosure also describes in-process devices, systems, and methods for entrapping air between the layers of film as they are wound onto a film roll. As a result, the film is less susceptible to damage and easier to use.
1. An apparatus for producing a film roll in-process, the apparatus comprising
a film with edge folds, each edge fold having a width;
an oscillating mechanism that oscillates the film for an oscillation rate at an oscillation distance; and
a winding mechanism that receives the film from the oscillating mechanism, comprising
a retractable idler roll that is parallel to a film roll and moves vertically away from the film roll at a separation rate that maintains an air gap between the retractable idler roll and the film roll as the film is wound onto the film roll horizontally.
2. The apparatus according to claim 1 , wherein the oscillation rate varies from 1 to 20 cycles per minute.
3. The apparatus according to claim 2 , wherein the oscillation rate is approximately 7.5 cycles per minute.
4. The apparatus according to claim 1 , wherein the oscillation distance is greater than the combined width of the edge folds.
5. The apparatus according to claim 4 , wherein the oscillation distance is approximately ⅛ inch greater than the combined width of the edge folds.
6. The apparatus according to claim 1 , wherein a mechanical system is used to control the retractable idler roll and to maintain the air gap.
7. The apparatus according to claim 6 , wherein the mechanical system is chosen from the group consisting of jack screw assemblies, linear actuators, cams, pneumatically driven systems, and hydraulically driven systems.
8. The apparatus according to claim 1 , wherein a mechanical system controls the separation rate at which the retractable idler roll moves away from the film roll.
9. The apparatus according to claim 8 , wherein the mechanical system is operated by a programmable logic control (PLC) system.
10. The apparatus according to claim 1 , wherein the air gap between the retractable idler roll and the film roll varies from 0 to 5 inches.
11. The apparatus according to claim 10 , wherein the air gap between the retractable idler roll and the film roll is approximately 1 inch.
12. An in-process method for winding film onto a film roll, the method comprising the steps of
providing a film with edge folds, each edge fold having a width;
oscillating the film with an oscillating mechanism;
passing the film over a retractable idler roll that is parallel to the film roll and move vertically away from the film roll at a separation rate that maintains a distance between the retractable idler roll and the film roll;
passing the film across the distance; and
winding the film onto the film roll horizontally.