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:
Jul. 08, 2003
Filed:
Feb. 14, 2001
Gopichandra Surnilla, West Bloomfield, MI (US);
Grant Alan Ingram, West Lafayette, IN (US);
Ford Global Technologies, LLC, Dearborn, MI (US);
Abstract
An engine air/fuel controller is responsive to an exhaust gas oxygen sensor positioned upstream of a catalytic converter and a proportional exhaust gas oxygen sensor positioned downstream of the catalytic converter. An air/fuel ratio signal provided by the downstream exhaust gas oxygen sensor is adjusted by a correction bias value. A first preferred method of deriving the correction bias value includes calculating the difference between the average of the upstream and downstream air/fuel ratios when the upstream sensor indicates lean operation of the engine. The second preferred method includes deriving the correction bias according a pre-determined and pre-programmed correction bias function, which provides correction bias values as a function of the of the air/fuel ratio measured by the downstream sensor.