Method for correcting the measuring errors of a hot-film air-mass meter

US5241857A · kind A · utility

Assignee

• Robert Bosch GmbH · DE

Inventors

• Eberhard Schnaibel · Hemmingen, DE
• Erich Junginger · Stuttgart, DE
• Klaus Hirschmann · Leonberg, DE

Key dates

• Filing date: Apr 1, 1992
• Grant date: Sep 7, 1993
• Expiry date: Apr 1, 2012

Classification

• Technology area (CPC G): Physics
• CPC primary: G01F1/72
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A method for correcting a measuring error of a hot-film air-mass meter occurring as the result of backflow, in particular for acquiring the air mass of the combustion air of an internal-combustion engine. It is proposed for an errorfree acquisition that the air volume be measured with the hot-film air-mass meter as a first value (23) and further as a second value 24 with a second method for determining air volume (.alpha./n method), which works independently of the hot-film air-mass meter; that the two values (23, 24) be drawn upon alternatively as a valid variable dependent upon the operating ranges determining the measuring reliability; and that in at least one operating range which is free of backflow for a correction signal (K.sub.H) to be extracted from a comparison of the first (23) and the second value (24) and used to correct the second value (24) in operating ranges showing backflow.