Piezoelectric pressure sensor
US5209125A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 27, 1991 |
| Grant date | May 11, 1993 |
| Priority date | — |
| Expiry date | Mar 27, 2011 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S73/04
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A vortex sensor 14 measures a flow rate of a fluid flowing through a flow passage by detecting alternating pressure variations 26a and 28a generated by a shedding body 16 placed in the flow passage. The vortex sensor 14 includes a sensor housing 32 enclosing piezoelectric sensing elements 62, 64 which are acted on by a movable member 30. The lifetime of the sensing elements in the closed interior is enhanced by providing surface barriers, oxidizing exposed interior surfaces, or providing a gas reservoir. In applications where fluid leakage may be accepted, a controlled leak restrictor provides a limited rate diffusion path to the atmosphere allowing a minimum partial pressure of oxygen to be maintained.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.