Stretch wrapping apparatus and process
US4418510A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 17, 1981 |
| Grant date | Dec 6, 1983 |
| Priority date | — |
| Expiry date | Apr 17, 2001 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB65B11/04
- 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 sets of powered rollers driven at different speeds to elongate the plastic film beyond its yield point and simultaneously connecting the stretched film to a rotating load whose surface is moving at approximately the same rate of speed as the surface of the faster and final of the two sets of rollers. A powered or force loaded film accumulator such as a dancer bar can be added to compensate for corners of the load where significant length-width distortions exist. In addition, a web narrowing device may be placed upstream or downstream from the rollers to reduce the hazard of edge tear under high elongation forces. Closure of the film ends can be accomplished by a mechanical closure mechanism.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.