Method and apparatus for examining a workpiece
US4644271A · kind A · utility
14Cited by
8References
17Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Feb 25, 1985 |
| Grant date | Feb 17, 1987 |
| Priority date | — |
| Expiry date | Feb 25, 2005 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N27/9046
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An eddy current inspector for imaging of a workpiece shape. A differentially wound test coil mounted next to a workpiece path of travel is energized with a time varying signal to set up eddy currents in the workpiece. A field modifying sleeve is rotated with the field to periodically disrupt the eddy current inducing field. Two signals from the coil, a flaw signal and a shape signal, are time multiplexed and scaled to present a real time image of a workpiece surface as well as the orientation and severity of flaws existing at the workpiece surface.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.