Film web drive stretch wrapping apparatus and process
US4302920A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 21, 1979 |
| Grant date | Dec 1, 1981 |
| Priority date | — |
| Expiry date | Nov 21, 1999 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB65B11/045
- WIPO fieldHandling
- WIPO sectorMechanical engineering
Abstract
A process and apparatus for applying stretchable plastic film to loads for containment of the loads using two connected rollers driven by the film web so that the rollers are driven at different speeds to elongate the plastic film beyond its yield point and wrapping the elongated film after it has been stretched past its yield point around a rotating load. A roller can be added to the apparatus to increase the set time for the elongated film after it is stretched by the connected rollers. In addition, a web narrowing device may be placed upstream or downstream from the apparatus to reduce the hazard of edge tear under high elongation forces.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.