Method and apparatus for forming element-free spaces in slide fastener chains
US4638542A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 22, 1984 |
| Grant date | Jan 27, 1987 |
| Priority date | — |
| Expiry date | Jun 22, 2004 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T29/53309
- WIPO fieldOther consumer goods
- WIPO sectorOther fields
Abstract
A punch blade depresses the coupling heads of a length of successive filamentary coupling elements toward a knockout blade while sandwiching stringer tapes between upper and lower grippers. The punch blade is lowered until lower legs of the coupling elements are cut off by cutter blades. The punch blade and the knockout blade are then lifted while gripping the severed coupling elements therebetween to forcibly remove the coupling elements out of engagement with sewing threads on the stringer tapes. The upper grippers have confronting steps for engaging the sewing threads so that the severed coupling elements can be detached reliably and smoothly from the stringer tapes without unduly tensioning the sewing threads and stringer tapes. The punch blade may have a vertical reinforcement member attached to at least one side edge thereof and having a lower tooth projecting downwardly beyond a lower edge for being pressed against the coupling elements. The lower tooth enters between adjacent coupling elements to position the coupling elements against unwanted longitudinal displacement with respect to the punch blade.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.