Overlock sewing machine and thread chain back-tacker therefor
US5513588A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 7, 1994 |
| Grant date | May 7, 1996 |
| Priority date | — |
| Expiry date | Nov 7, 2014 |
Classification
- Technology area (CPC D)Textiles; Paper
- CPC primaryD05D2305/345
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
A thread chain back-tacker for an overlock sewing machine eliminates defective back-tacking. The back-tacker includes a thread chain cutter, an adjuster for adjusting the length of free thread chain after the end of back-tacking, a presser foot, an air nozzle, a thread drawing nozzle, a thread clamp cylinder, a nozzle swing cylinder, a nozzle pulling cylinder, a cylinder retainer coupling the nozzle swing cylinder and nozzle pulling cylinder together, a position adjuster bolt provided on the cylinder retainer for adjusting a stop position of the thread drawing nozzle, a speed setting/releasing unit, a venturi unit, an air breaking valve, and a solenoid for on-off operating the air breaking valve. The presser foot includes a presser body, a presser foot chain shield secured to the rear end of the presser body, and a presser foot stitch tongue secured to a central portion of the presser body. The presser foot stitch tongue has its back surface provided with a groove for guiding a thread chain and also has a top guide for guiding the thread chain into the groove. Not only is it possible to eliminate curling of the cloth end at the start of back-tacking and projection of the thread cha…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.