Pressure sensing cell using brittle diaphragm
US4578735A · kind A · utility
Inventors
Key dates
| Filing date | Oct 12, 1984 |
| Grant date | Mar 25, 1986 |
| Priority date | — |
| Expiry date | Oct 12, 2004 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T29/43
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A capacitive sensing cell is adapted for manufacture in a batch process, and uses a substrate or base from a rigid insulating material such as glass and a diaphragm assembly of a brittle semiconductor. The diaphragm assembly and the substrate are anodically bonded together. A very shallow recess is formed on either the diaphragm or the substrate to accommodate a deposited capacitor plate. Two such assemblies are connected together and the assembly is filled with noncompressible fluid to slightly bow the diaphragms away from the substrates. Differential pressure between the diaphragm assemblies is sensed by detecting the relative positions of the two diaphragms.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.