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:
Jun. 24, 1997
Filed:
Apr. 11, 1995
Hirofumi Ohuchi, Himeji, JP;
Shinya Fujimoto, Himeji, JP;
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
A dual-sensor type air-fuel ratio control system for an internal combustion engine. A catalytic converter 10 is disposed in an exhaust pipe 9, together with a first upstream air-fuel ratio sensor 11 and a second, downstream air-fuel ratio sensor 12. An electronic unit 30A controls the air-fuel ratio of a mixture supplied to the engine, and includes first and second arithmetic circuits 51, 52 for determining first and second air-fuel ratio control quantities Cf1, C2' on the basis of the first and second air-fuel ratio signals V1, V2, and a circuit 53, 54 for correcting the first control quantity with the second one to determine a target air-fuel ratio control quantity J for the fuel injection. A filter 50 is provided for the first air-fuel ratio signal to compensate for variations in the output characteristic of the first sensor.