Patent · US Expired

Temperature compensation in mass flow sensors employing the hot-wire anemometer principle

US5656938A · kind A · utility

4Cited by

2References

6Claims

0Family size

Assignee

DAUG Deutsche Automobilgesellschaft mbH · DE

Inventors

Thomas Bennohr · Braunschweig, DE
Michael Daetz · Wolfsburg, DE

Key dates

Filing date	Jan 26, 1995
Grant date	Aug 12, 1997
Priority date	—
Expiry date	Jan 26, 2015

Classification

Technology area (CPC G)Physics
CPC primaryG01F1/698
WIPO fieldMeasurement
WIPO sectorInstruments

Abstract

For determining the air mass flow in the intake pipe of an internal combustion engine by means of an electrical bridge, normally the current flowing through the current measurement resistor when balancing the bridge is evaluated as an indirect measure of the air mass flow. The primary measured quantity for the air mass flow is, however, the power converted at the air flow measurement resistor around which the air flows so that the indirect measurement always includes an error. To reduce this measurement error, the invention utilizes the evaluation of the sum of the voltage across the current measurement resistor and the voltage or a partial-voltage across the air flow measurement resistor as a measure of the air flow.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.