Method and apparatus for detecting broken sewing needles in sewn articles
US5923165A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 8, 1997 |
| Grant date | Jul 13, 1999 |
| Priority date | — |
| Expiry date | May 8, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01V3/08
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Disclosed are a method and apparatus for detection of a magnetic substance erroneously included in a non-magnetic product. The non-magnetic product such as a sewn product is passed through a high magnetic field in which a magnetic field is applied to the product. The residual magnetization of a magnetic substance such as a broken needle mingled in the product is detected by a sensing unit and a signal of detection is transmitted to a measuring unit to measure the magnitude of detected residual magnetization. The presence or absence of the magnetic substance in the product is determined by a control unit based on the output from the measuring unit. Alternatively, a magnetic field may be preparatorily applied to a magnetic substance having the possibility of being mingled in the non-magnetic product thereby causing the magnetic substance to assume a state of possessing residual magnetization.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.