Optical differential pressure transducer utilizing a bellows and flexure system
US7047816B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 21, 2003 |
| Grant date | May 23, 2006 |
| Priority date | — |
| Expiry date | Jul 2, 2023 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01L11/025
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A pressure transducer that uses a rhomboidal flexure to provide displacement amplification to an optical sensing element is disclosed. The transducer includes an optical sensor disposed between sides of the flexure. The top portion of the flexure connects to a displacement device, such as a bellows. A first pressure port provides a first pressure to the bellows. A second pressure, preferably greater than the first pressure, is ported into a housing containing the flexure, which tends to compress the bellows and pull apart or expand the flexure. Such expansion pinches or compresses the optical sensing element between the sides of the flexure, and in particular stresses an optical sensing element containing a fiber Bragg grating. Assessing the Bragg reflection wavelength of the grating allows the differential pressure to be determined, although the transducer can also be used to sense an absolute pressure. A temperature compensation scheme, including the use of additional fiber Bragg gratings and thermal compensators axially positioned to counteract thermal effects of the optical sensing element, is also disclosed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.