Electro-magnetic thread tension control for sewing machines
US4301978A · kind A · utility
4Cited by
13References
1Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Apr 5, 1979 |
| Grant date | Nov 24, 1981 |
| Priority date | — |
| Expiry date | Apr 5, 1999 |
Classification
- Technology area (CPC D)Textiles; Paper
- CPC primaryD05D2207/05
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
A tension device for sewing machines is disclosed having thread tensioning discs and a linear actuator for applying a compressive force between the discs. The invention is characterized in that for any given tension setting of the device, the applied compressive force, or tension, remains constant regardless of any variations in the spacing of the discs due to variations in the thread thickness, up to the range of travel of the linear actuator.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.