Presser bar biasing spring structure
US4342272A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 3, 1979 |
| Grant date | Aug 3, 1982 |
| Priority date | — |
| Expiry date | Oct 3, 1999 |
Classification
- Technology area (CPC D)Textiles; Paper
- CPC primaryD05B29/02
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
A tension spring concentric with the presser bar pulls the presser foot down against the work. The spring is threaded onto two holders, each of which fits around the presser bar. The first holder is attached to the presser bar near its upper end but the second allows the presser bar to slide within it. The second holder is slidably attached to a bracket and controlled by a presser bar pressure regulating cam to slide up and down in the bracket and thereby change the tension in the spring to exert a controlled force on the presser foot. The first holder is also slidably mounted in the bracket, and is controlled by a lever that has a lifting cam linked to the first holder. When the lever is lifted, the first holder is lifted to raise the presser bar and presser foot away from the work. This extends the spring, which urges the presser foot back down against the work as soon as the lever is lowered.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.