Degradation and contamination compensated tuning fork quartz monometer, and method to compensate for tuning quartz degradation and contamination
US4995265A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 14, 1989 |
| Grant date | Feb 26, 1991 |
| Priority date | — |
| Expiry date | Dec 14, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01L21/22
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
In the present pressure measurement process the damping signal of a tuning fork quartz manometer, which is a measure of the prevailing pressure, is so combined with the correction value proportional to the resonant frequency that a measurement result is obtained, which is independent of any contamination of the tuning fork quartz. Apart from the resonant frequency (f.sub.R) of the measuring quartz (11), preferably also the resonant frequency (f.sub.R ') of a reference quartz (21) kept at constant pressure is determined. Thus, the damping signal (R.sub.S) can be corrected by a correction value proportional to the difference between the two reference frequencies (R.sub.R '-f.sub.R), which is substantially temperature-independent.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.