Device for detecting an overlapping edge of material on a sewing machine
US4696246A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 29, 1986 |
| Grant date | Sep 29, 1987 |
| Priority date | — |
| Expiry date | May 29, 2006 |
Classification
- Technology area (CPC D)Textiles; Paper
- CPC primaryD05B69/24
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
A device for detecting an overlapping edge of material on a sewing machine has, in combination, a signal-level discriminator and an optical waveguide. The optical waveguide has a light-receiving end on the sewing machine for receiving light through the overlapping edge of the material. The optical waveguide may be an optic fiber which, because of its small, flexible size can be accommodated easily even in the crowded sewing head or bed of an industrial sewing machine. The other end of the optical waveguide is remote from the light-receiving end for providing the received light to the signal-level discriminator which, therefore, is also remote from the crowded sewing head or bed of the sewing machine which, in addition, could interfere with its operation. For operation, the signal-level discriminator has an electro-optic sensor responsive to the light from the optical waveguide and a detector electrically responsive to light sensed by the electro-optic sensor for determining an absolute, light-intensity value of the sensed light which, therefore, detects the overlapping edge of the material accurately the corresponding change in determined light intensity.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.