Method and apparatus for the manufacture of plastic bags having interlocking profile extrusions
US4618383A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 5, 1985 |
| Grant date | Oct 21, 1986 |
| Priority date | — |
| Expiry date | Mar 5, 2005 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T156/1015
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
In the manufacture of plastic bags having interlocking profiled extrusions for the closure, the extruded plastic profiles are applied to a moving web of film immediately after extrusion of the profiles. The profiles are fused to the web on a first section of a fusing/cooling arcuate plate-like support member. Thereafter, the web is moved to a second cooled section of the arcuate plate-like support which is maintained at a temperature to allow the profiles to freeze to the web. The moving web of film is maintained under tension so that contraction of the film upon release compensates for the contraction of the locking profile as it cools to prevent puckering of the web. The locking profiles are applied to the web in an in-line process, which includes folding and heat sealing the moving web of film to form plastic bags.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.