Apparatus for measuring the speed of flow of flowable media
US4389899A · kind A · utility
Inventor
Key dates
| Filing date | Oct 24, 1980 |
| Grant date | Jun 28, 1983 |
| Priority date | — |
| Expiry date | Oct 24, 2000 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01P5/18
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The speed of a flowing medium is measured by determining the transit time of sound pulses transmitted alternately in opposite directions between first and second transmitter-receivers 23, 24 spaced apart in the direction of flow. A processing circuit 18, 19, 20 evaluates the speed of flow from the difference between the transit times in the two directions. The transit times in the two directions are measured by separate but identical first and second pulse circuits 11, 11'. Each pulse circuit includes a variable frequency generator 13 the frequency of which is so regulated by the transmitted pulse from the pulse generator 12 and the pulse E received from the associated transmitter-receiver that the reciprocal of its frequency is equal to the transit time in the associated direction. Delay circuitry 21 is able to delay the trigger pulse applied to the frequency generator 13 from the pulse generator 12 so as to take account of transit time errors in the apparatus.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.