Overpressure-protected, differential pressure sensor
US5357808A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 26, 1993 |
| Grant date | Oct 25, 1994 |
| Priority date | — |
| Expiry date | Mar 26, 2013 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T29/49996
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An overpressure-protected, differential pressure sensor (37) is formed by depositing diaphragm material (24) over a cavity (23) formed and filled with sacrificial material (22) into a front surface of a substrate. The sacrificial material (22) is then removed to create a free diaphragm. The floor of the cavity (23) defines a first pressure stop to limit the deflection of the diaphragm in response to pressure applied to the top of the diaphragm. A port (33) is created to allow pressure to be applied to the bottom side of the diaphragm (24). An optional second pressure stop, which limits the deflection of the diaphragm in response to pressure applied to the bottom side of the diaphragm, is formed by bonding a cap (35) to stand-offs (34) placed around the top of the diaphragm. The stand-offs are spaced to allow pressure to be applied to the top of the diaphragm.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.