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. 07, 1995
Filed:
Sep. 27, 1993
Daniel V Orzel, Westland, MI (US);
Ford Motor Company, Dearborn, MI (US);
Abstract
A control system which provides air/fuel feedback control while measuring catalytic converter efficiency. An efficiency test period is provided when the count in transitions of a signal related to an upstream exhaust gas oxygen sensor reaches a maximum count for a plurality of inducted airflow ranges. During the test period, three separate ratios indicating converter efficiency are provided. These ratios include: a ratio of downstream exhaust gas oxygen sensor total amplitude to a feedback variable derived from the upstream sensor; a ratio in frequency of transitions of the downstream sensor to frequency of the feedback variable; and a ratio of areas derived from the downstream sensor and feedback variable. When all three ratios indicate degraded converter efficiency, an overall indication is provided.