Fluid flow amount measuring apparatus responsive to fluid flow in forward and reverse directions
US6862930B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 19, 1999 |
| Grant date | Mar 8, 2005 |
| Priority date | — |
| Expiry date | Oct 19, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01F1/699
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
In a thermal-type air flow measuring apparatus, a heater is set to a reference temperature which is a predetermined temperature higher than an intake air temperature detector. A flow amount detector is disposed at an upstream side of the heater with respect to a forward direction of an intake air flow. The heater is turned at a plurality of points in a direction perpendicular to the forward direction of the intake air flow and has a predetermined width in the intake air flow direction so that heat transfers less in the intake air flow direction in the heater. If the intake air flow direction reverses, the temperature distribution in the heater also reverses. As a result, an intake air amount varying in response to the air flow direction is detected by comparing the temperature of the flow amount detector with the reference temperature.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.