Method and an apparatus for forming cut-outs and transverse welding-seams in a sheet of film
US6511572B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 10, 2001 |
| Grant date | Jan 28, 2003 |
| Priority date | — |
| Expiry date | Jul 10, 2021 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T156/1056
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
The invention relates to a method of forming cutouts (4) and transverse welding seams (10) in a sheet of film (5) that is advanced continuously at high velocity, wherein the cutouts (4) constitute areas that are delimited by cutting lines (6, 7), wherein the method comprises the following steps: a) the formation of the cutouts (4) in a sheet section with high sheet tension with cutting lines (7) that extend longitudinally of the sheet of film (5), and cutting lines (7) that extend transversely of the sheet of film, said cutting lines featuring a number of interruptions (8) that constitute support points whereby the cutouts (4) continue to be coherent with the sheet of film (5) at the support points, b) subsequent formation of the transverse welding seams (10) in a sheet section with low sheet tension.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.