Direct-heated gas-flow measuring apparatus
US4785662A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 12, 1986 |
| Grant date | Nov 22, 1988 |
| Priority date | — |
| Expiry date | Nov 12, 2006 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01F1/6983
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A direct-heated gas-flow measuring apparatus including a measuring tube disposed in the gas stream, a film resistor for generating heat and detecting the temperature thereof, and a feedback control circuit for controlling the heat generated by the film resistor so that the temperature of the film resistor is a predetermined value. Provided at least at the upstream side of the film resistor near thereto is a shield for reducing the accumulation of deposits on the film resistor. The shield and the film resistor have substantially the same thickness to satisfy the condition: EQU l/t.ltoreq.50 where l is a distance therebetween and t is a thickness thereof.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.