Bobbin thread level detection and display arrangement for a sewing machine
US4333411A · kind A · utility
6Cited by
14References
3Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Jul 15, 1981 |
| Grant date | Jun 8, 1982 |
| Priority date | — |
| Expiry date | Jul 15, 2001 |
Classification
- Technology area (CPC D)Textiles; Paper
- CPC primaryD05D2205/16
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
A bobbin thread level detection and display arrangement for a sewing machine includes an array of light emitting diodes which are activated to convey to the sewing machine operator an indication of the quantity of thread left of the bobbin. To control the light emitting diodes, an arrangement utilizing a light source and a phototransistor is arranged proximate the bobbin. The circuitry for controlling the activation of the light emitting diodes also provides for a "fading in" of the individual light emitting diodes to provide a display in the nature of a bar graph.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.