The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 14, 2006
Filed:
Jul. 28, 2003
Werner Frie, Regensburg, DE;
Christoph Haberer, Regensburg, DE;
Harald Liederer, Woerth, DE;
Siemens Aktiengellschaft, Munich, DE;
Abstract
In a method for determining a mass airflow in an air duct using a mass airflow sensor, sensor signals at successive times, indicating the magnitude of the mass airflow, are captured and, using a characteristic curve for the mass airflow sensor, corresponding values are determined for the mass airflow. In doing so, a time series of signals is subjected to a vibration analysis, which determines a fundamental vibration and at least one prescribed harmonic vibration of the fundamental vibration, and the existence of a backflow is established if the ratio of the strength of the harmonic vibration to the strength of the fundamental vibration exceeds a prescribed threshold value.