Acoustical wave flowmeter with increased density capability
US4509372A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 4, 1983 |
| Grant date | Apr 9, 1985 |
| Priority date | — |
| Expiry date | Apr 4, 2003 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01F1/667
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
In a flowmeter system having a transducer assembly defining a path for confining the flow of fluid medium there through and with first and second acoustic transducer elements disposed along said flow path for generating and receiving acoustic compression waves in the fluid medium, a phase-locked loop transmitter/receiver system including a voltage-controlled oscillator for adjusting the frequency of the acoustic compression waves to maintain the compression wavelength constant, together with circuitry for measuring the phase difference of the received acoustic compression waves relative to the applied electrical signal and circuitry for producing a signal representative of both the velocity of sound in the fluid medium and the direction and magnitude of the flow, the improvement in the circuitry which enables operation over a wider range of fluid density by causing the operating phase of the system phase-locked loop to vary in a continuous manner according to a previously determined relationship of phase-versus-resonant frequency, and the loop acquisition frequency to vary in a continuous manner according to a previously determined relationship of amplitude-versus-resonant frequenc…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.