Apparatus and method of checking the thickness and uniformity of a coating deposited on an elongated insulating body using a condenser sensor as part of a resonant electrical circuit
US5418467A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 25, 1993 |
| Grant date | May 23, 1995 |
| Priority date | — |
| Expiry date | Jun 25, 2013 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01B7/087
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
This invention concerns an apparatus for checking the thickness and uniformity of a coating made of conducting material deposited on an elongated insulating body, this apparatus comprising: PA1 a sensor sensitive to the presence of the elongated body and forming part of an electrical circuit powered by a power supply voltage (24), PA1 measurement instruments (25) to measure an electrical quantity that is a function of the thickness of the conducting coating, at the output of the circuit PA1 equipment for processing the electrical quantity to deduce the thickness of the conducting coating, wherein the sensor consists of a condenser (10) containing two plates separated from each other by an air gap containing a dielectric material, this condenser being adapted to enable the elongated body to pass through the air gap.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.