Apparatus and method for in-line calibration verification of mass flow meters
US5359878A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jan 25, 1994 |
| Grant date | Nov 1, 1994 |
| Priority date | — |
| Expiry date | Jan 25, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01F1/6888
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An apparatus for verifying the calibration of a flow meter contains a flow sensor assembly which has a flow tube defining an axial fluid path through the flow sensor assembly; an upstream resistance thermometer in thermal contact with the flow tube; a downstream resistance thermometer in thermal contact with the flow tube, where the two thermometers are operationally connected to a means for producing an output in response to a difference between the heat flows from the first and second resistance thermometers; and means for asymmetrically transferring heat to the first and second resistance thermometers, independently of fluid flow through the flow tube. The calibration of the flow meter's thermal and electronic systems is verified by measuring the flow meter's output in response to a first asymmetric heat transfer, to the upstream and downstream resistance thermometers, when the flow meter is calibrated. The output of the flow meter in response to a second asymmetric transfer, to the upstream and downstream thermometers, is subsequently measured and comparison of the two readings verifies whether the flow meter's thermal and electronic systems remains calibrated.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.