Method and apparatus for measuring pressure with fiber optics
US5714680A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 4, 1993 |
| Grant date | Feb 3, 1998 |
| Priority date | — |
| Expiry date | Nov 4, 2013 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01L9/0079
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method and apparatus are provided for measuring pressure in a combustion chamber of an internal combustion engine is provided with a non-intrusive, metal-embedded fiber optic pressure sensor. A Fabry-Perot Interferometer is arranged in a terminated, single mode fiber to function as a pressure gauge. The fiber Fabry-Perot Interferometer (FFPI) is embedded in a metal part which is disposed in the cylinder head of the engine. The metal part and FFPI experience a longitudinal compression in response to the pressure in the chamber. In another aspect of the invention, a non-intrusive fiber containing the FFPI is embedded in a hole drilled or otherwise provided in the metal housing of a spark plug. The spark plug is threaded into the cylinder head of an internal combustion engine and is directly exposed to the combustion chamber pressure. Consequently, the spark plug housing and FFPI experience a longitudinal strain in response to the pressure in the chamber.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.