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:
Nov. 20, 2012
Filed:
Apr. 17, 2009
Nicole Fuhrmann, Lappersdorf, DE;
Stefan Seyfferth, Regensburg, DE;
Nicole Fuhrmann, Lappersdorf, DE;
Stefan Seyfferth, Regensburg, DE;
Contitnental Automotive GmbH, Hannover, DE;
Abstract
An internal combustion engine has an exhaust gas tract with a first and a second exhaust gas catalyst downstream of the first one, a first exhaust gas sensor, which is disposed upstream or in the first catalyst, and a second exhaust gas sensor, which is disposed downstream of the first catalyst and upstream of the second catalyst. During trailing throttle operation, the measurement signal of the second sensor is monitored for a signal characteristic that is typical of a maximum possible saturation state with oxygen that the first catalyst can achieve, upon which a characteristic variable is determined for a saturation state of the second catalyst with oxygen as a function of an engine operating variable. Outside the trailing throttle operation, an enrichment mode is controlled by enriching the air/fuel mixture, specifically as a function of the characteristic variable for the saturation state of the second catalyst with oxygen.