Material thickness measurement using magnetic information
US6586930B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 28, 2000 |
| Grant date | Jul 1, 2003 |
| Priority date | — |
| Expiry date | Apr 28, 2020 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01B7/10
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An apparatus for and a method of measuring material thickness with magnetics. The thickness monitoring system includes a thickness monitor, a probe, and a target. In a preferred embodiment, the probe is positioned on one side of an article for which the thickness is to be determined. The target is positioned on the opposite side of the article from the probe. The probe includes an excitation coil, a field compensation coil, and a magnetic sensor. The method includes energizing the excitation coil to excite a response from the target, compensating for the effect of the excitation coil on the magnetic sensor, measuring the response of the target with the magnetic sensor, and determining the thickness of the article from the measured response. The preferred mode of energizing the excitation coil is with an AC waveform; however DC, multi-frequency AC, or a combination of AC and DC waveforms may be used.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.