Device having active and reference coils for performing non-destructive inspection by eddy current
US6534976B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Mar 16, 2001 |
| Grant date | Mar 18, 2003 |
| Priority date | — |
| Expiry date | Apr 26, 2021 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N27/9046
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A device for inspecting a part by eddy currents, the device comprising at least one measurement bridge having an active coil which is connected between a first terminal and a second terminal, and a reference circuit which is connected between said second terminal and a third terminal, said first and third terminals being for connection to an AC voltage generator so that an alternating magnetic field is generated by the active coil in the part to be inspected in order to enable any variation in the impedance of the active coil on passing over a defect in a part under inspection to be detected by analyzing an output voltage of the device, wherein the reference circuit is a reference coil identical to the active coil, wherein the first terminal and the third terminal are for receiving voltages applied by the AC voltage generator which are equal in value and of opposite signs relative to a neutral phase of said generator, the output voltage being the voltage read between said second terminal and said neutral phase, and wherein the reference coil is electromagnetically isolated from the part to be inspected.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.