Eddy current flaw detector having rotatable field defining sleeve for selectively enhancing induced eddy currents in a workpiece
US4673879A · kind A · utility
11Cited by
12References
20Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jun 27, 1984 |
| Grant date | Jun 16, 1987 |
| Priority date | — |
| Expiry date | Jun 27, 2004 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB21B38/00
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Method and apparatus for scanning a generally cylindrical workpiece for flaws. A cylindrical metallic sleeve is rotatably supported about a workpiece path of travel. Two differentially wound energization coils surround the sleeve near two apertures in the sleeve. The coils are energized with a high frequency signal that induces eddy currents in the workpiece. The apertures periodically disrupt the eddy current inducing magnetic fields and enhances signals from the coils indicative of the presence of flaws in the workpiece.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.