Micro-mechanical capacitive inductive sensor for wireless detection of relative or absolute pressure
US7017419B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 31, 2004 |
| Grant date | Mar 28, 2006 |
| Priority date | — |
| Expiry date | Aug 31, 2024 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01L9/0073
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A micro-mechanical pressure transducer is disclosed in which a capacitive transducer structure is integrated with an inductor coil to form a LC tank circuit, resonance frequency of which may be detected remotely by imposing an electromagnetic field on the transducer. The capacitive transducer structure comprises a conductive movable diaphragm, a fixed counter electrode, and a predetermined air gap between said diaphragm and electrode. The diaphragm deflects in response to an applied pressure differential, leading to a change of capacitance in the structure and hence a shift of resonance frequency of the LC tank circuit. The resonance frequency of the LC circuit can be remotely detected by measuring and determining the corresponding peak in electromagnetic impedance of the transducer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.