Upper thread tension device of a sewing machine
US4611547A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 13, 1985 |
| Grant date | Sep 16, 1986 |
| Priority date | — |
| Expiry date | Jun 13, 2005 |
Classification
- Technology area (CPC D)Textiles; Paper
- CPC primaryD05B47/00
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
A thread tension device of a sewing machine having a fabric presser bar lifting lever, comprises a mount plate fixedly arranged in the sewing machine, a support shaft having one end secured to said mount plate, a pair of first and second thread tensioning disks coaxially mounted on the support shaft and having concentrically arranged curved thread clamping faces which are pressed against each other to clamp therebetween an upper thread of the sewing machine, a spring operated to adjustably press the disks against the mount plate, a thread tension adjusting member operated to increase or decrease an elastic force of the spring, an actuating plate and a transmission rod having one end connected to the actuating plate and the other end operatively connected to the fabric presser bar lifting lever. The transmission rod is operated to actuate the actuating plate to thereby turn the first thread tensioning disk axially of the support shaft on a fulcrum provided by one end portion of the curved thread clamping face of the first thread tensioning disk, so as to move an opposite end portion of the thread clamping face of the first thread tensioning disk away from the second thread tensionin…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.