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. 01, 2000
Filed:
Oct. 16, 1998
Christopher Kirk Davey, Novi, MI (US);
Robert Joseph Jerger, Livonia, MI (US);
Ford Global Technologies, Inc., Dearborn, MI (US);
Abstract
A system and method for monitoring emissions by monitoring performance of a catalytic converter using a predetermined indicated threshold value include determining a current value for the indicator based on signals generated by at least one exhaust gas sensor, modifying a historical indicator value based on the current value, and adjusting the predetermined indicator threshold based on the historical indicator value. The predetermined indicator threshold is adjusted provided various adapt criteria are satisfied. The historical indicator value is compared to the threshold to determine whether to generate a malfunction indicator signal. In one embodiment, emissions are indicated using a switch ratio based on the number of switches or transitions for upstream and downstream exhaust gas oxygen sensors.