Eddy current flaw detector using a pair of parallel resonant circuits and a negative resistance in parallel with each circuit
US4050011A · kind A · utility
3Cited by
3References
5Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Nov 14, 1975 |
| Grant date | Sep 20, 1977 |
| Priority date | — |
| Expiry date | Nov 14, 1995 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N27/9046
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
When a negative resistance is connected in parallel to a parallel resonance circuit composed of coil and condenser for detecting flaws and other defects of a travelling metal material, the detecting system is capable of improving sensitivity for detecting said flaws and lowering the required degree of amplification of the following amplifier, consequently reducing influence depending upon unbalance of a bridge circuit. At the same time, the simplifying of the power source of said system may be easily realized.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.