Method for locating weft thread defects in fabric
US4791481A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 18, 1987 |
| Grant date | Dec 13, 1988 |
| Priority date | — |
| Expiry date | Jun 18, 2007 |
Classification
- Technology area (CPC D)Textiles; Paper
- CPC primaryD06H3/12
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A process for locating weft thread defects in woven fabrics includes using a macro (close-up) lens and video camera to produce an enlarged image of the fabric, and then observing and evaluating the weft pattern from the video generated image. Transmissive and reflecting illumination may be used on the fabric to enhance the video image. Evaluation and measurement of weft thread positions is carried out by direct visual observation or by using computerized pattern recognition systems with micro processor techniques involving digitizing the video image. A relaxation defect of weft thread is determined by measuring variation between weft thread spacing when the fabric is viewed from two different viewing angles.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.