Air flow rate measuring apparatus
US6520009B2 · kind B2 · utility
3Cited by
7References
6Claims
0Family size
Assignees
Inventors
Key dates
| Filing date | Jan 3, 2002 |
| Grant date | Feb 18, 2003 |
| Priority date | — |
| Expiry date | Jan 3, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01F1/6965
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An air flow rate measuring apparatus generates a flow rate signal with a nonlinear characteristic from a flow rate detecting unit provided with a heat generating resistor and converts that into a signal with a linear characteristic by a linearizing circuit. Then, the flow rate signal is smoothed by a filter circuit to obtain a signal in which the measurement error due to a flow rate ripple is suppressed. Thereafter, the flow rate signal is again formed into a signal with a nonlinear characteristic by a nonlinear-form converting circuit to suppress resolution lowering due to analog-to-digital conversion.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.