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:
Jan. 14, 1997
Filed:
Sep. 13, 1995
Hanno Jelden, Lehre, DE;
Winfried Schultalbers, Meinersen, DE;
Thomas Bizenberger, Braunschweig, DE;
Volkswagen AG, Wolfsburg, DE;
Abstract
For continuous and accurate monitoring of the conversion rate of an exhaust catalyst during operation of an internal combustion engine, temperature values are determined at two measuring points upstream and downstream of the catalyst in the direction of exhaust gas flow. In order to obtain an evaluatable signal difference at all times, at least one of the measured exhaust gas temperature values is filtered so that the temperature value obtained assures a reliable temperature difference with respect to the other temperature value at all times. The actual temperature difference value obtained in this way is compared with a desired temperature difference value generated by a three-dimensional desired value characteristic map and is checked with the aid of a plausibility check.