Pulsed eddy current sensor for precision measurement at-large lift-offs on metallic surfaces
US9091664B2 · kind B2 · utility
Inventors
Key dates
| Filing date | Jun 7, 2012 |
| Grant date | Jul 28, 2015 |
| Priority date | — |
| Expiry date | Sep 12, 2033 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N27/9053
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
There is described a pulsed eddy current sensor for measurement of a lift-off distance over a surface of a metallic substrate (a metallic surface). The pulsed eddy current sensor comprises: a primary excitation coil to which are applied voltage pulses for generating primary magnetic fields, wherein an interaction of the primary magnetic fields with the metallic substrate produces secondary magnetic fields; and secondary pick-up probes, each of the secondary pick-up probes located at a different vertical distance from the metallic surface, the secondary pick-up probes used for measuring the primary and secondary magnetic fields and for producing a differential signal that is representative of the lift-off distance.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.