Method and apparatus for opening a zipper after it has been spot sealed
US5873969A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 22, 1997 |
| Grant date | Feb 23, 1999 |
| Priority date | — |
| Expiry date | Aug 22, 2017 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T156/12
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
A method and apparatus for manufacturing recloseable plastic bags with engageable mating profiles where the bags are provided open for the consumer. The profiles are initially provided in the fully engaged condition within an elongate, longitudinally cut tube. The profiles are then periodically fused, tacked, or attached together at the approximate locations where the tube is to be cut into bags. Upon tacking, the profiles are pulled apart by frictionally engaging an area on the outside of the film, near the profiles, and between the tacks. The film is then forced away from the profiles, which at least partially pulls one profile from the other. Thereafter, the tube may be cut and sealed into bags as would otherwise normally occur.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.