Thermal flow sensor and method for operating same
US11988535B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 23, 2021 |
| Grant date | May 21, 2024 |
| Priority date | — |
| Expiry date | Jul 5, 2041 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01F1/712
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method for operating a thermal flow sensor includes: bringing a measuring medium into thermal contact with a sensor element of the flow sensor and periodically heating the medium using an AC voltage introduced into the sensor element; simultaneously detecting a maximum amplitude of a temperature and/or a phase shift between a curve of the AC voltage and the curve of the temperature; adjusting the detected maximum amplitude and/or the detected phase shift using calibration data; determining an isoline using the adjusted maximum amplitude and/or the adjusted phase shift based on model of the flow sensor, wherein the isoline has a plurality of value pairs of thermal conductivity and thermal capacitance of the medium; deriving a medium information from the isoline; and performing a flow measurement by converting signal values from the sensor element into measurement values of an effective flow velocity of the medium using the medium information.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.