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:
Aug. 03, 1999
Filed:
Dec. 20, 1996
Applicant:
Inventors:
Uwe Kammann, Warberg, DE;
Harald Loeck, Wolfsburg, DE;
Assignee:
Volkswagen AG, Wolfburg, DE;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
F01N / ;
U.S. Cl.
CPC ...
60274 ; 60276 ; 60277 ;
Abstract
To improve monitoring of the conversion rate of an exhaust catalyst for an internal combustion engine, the HC emissions are determined downstream of the exhaust catalyst during a predetermined time interval. The time interval starting point and the time interval duration are dependent on the operating mode of the internal combustion engine which is detected, for example, by consideration of the fuel mass flow to the engine over time. The HC sum value thus accumulated during the time interval is compared with a limit value and, when a predetermined difference value results, an error signal is generated.