Capacitive pressure transducer
US4227419A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 4, 1979 |
| Grant date | Oct 14, 1980 |
| Priority date | — |
| Expiry date | Sep 4, 1999 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01L9/0075
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A highly linear capacitive pressure transducer system includes one or more conductive plates mounted on a diaphragm for deflection toward and away from another conducting plate. The opposed conductive plates include both a main variable capacitor and a small separate compensation capacitor mounted on the same structure. The small compensation capacitor is connected in parallel with a larger fixed reference capacitor. The outputs from the main variable capacitor, and from the reference capacitance including the fixed capacitor and the small variable capacitor, are compared in electronic circuitry which produces an output signal proportional to the variations in pressure applied to the diaphragm. When the small variable capacitor has a change in capacitance with pressure generally of the same order of magnitude as the deviations from linearity of the main variable capacitor, the linearity of the output signal with changes in pressure is significantly increased.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.