Pressure sensor
US4935841A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Oct 4, 1989 |
| Grant date | Jun 19, 1990 |
| Priority date | — |
| Expiry date | Oct 4, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01L9/0075
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A capacity pressure sensor having a housing and a diaphragm. The housing and the diaphragm are substantially flat and are connected to each other at an upstanding border at the periphery of the housing. In the hermetically closed space between the housing and said diaphragm a reference pressure is applied. In a pressure measurement the diaphragm is bent inwards relative to said housing depending on the pressure acting on the surface of said diaphragm. This bending inwards is a primary output signal which capacitively can be converted to an electrical signal. Inside the pressure sensor on the inner surfaces of said housing and said diaphragm there are arranged, for the detection of the position of said diaphragm relative to said housing, capacitor plates connected to an electrical measuring circuit for detection of the capacity of the capacitor formed thereby. To enhance the linearity of the measuring capacitor the outer flat surfaces of the pressure sensor are coated with conducting layers connected to earth. Furthermore, in the housing a recess is arranged which when given suitable dimensions further reduces the deviation of the pressure sensor from the desired linear characterist…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.