Thread spreading apparatus for use in overlock sewing machine
US5467725A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 6, 1994 |
| Grant date | Nov 21, 1995 |
| Priority date | — |
| Expiry date | Jun 6, 2014 |
Classification
- Technology area (CPC D)Textiles; Paper
- CPC primaryD05B61/00
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
A thread spreading apparatus for use in an overlock sewing machine capable of performing over-edge chain stitching and other stitching. The thread spreading apparatus uses a lower looper for over-edge chain stitching to allow a needle to surely drop into a triangle defined by a needle thread, a looper thread and the lower looper, thereby enabling multi-thread chain stitching and covering chain stitching to be performed without fail. The apparatus includes a thread spreading hook having hook portions with different heights for retaining needle threads and a projection formed on one of the hook portions. During stitching other than over-edge chain stitching, the hook portions of the thread spreading hook retain the needle threads when two needles drop, thereby allowing each needle to drop into a triangle defined by the looper thread, the lower looper and the corresponding needle thread. During over-edge chain stitching, the hook portions lie rearwardly of an idle chain stitch forming bore provided in a needle plate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.