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:
Aug. 22, 1989
Filed:
Mar. 07, 1988
Shuichi Hosoi, Wako, JP;
Sachito Fujimoto, Wako, JP;
Abstract
A method of controlling the air-fuel ratio of a mixture being supplied to an internal combustion engine, in a feedback manner responsive to output from an O.sub.2 sensor arranged in the engine exhaust system for sensing the concentration of a component in exhaust gases from the engine to produce as the output a normally fluctuating output signal indicative of the concentration. The air-fuel ratio is controlled to a desired value by means of at least one of proportional control applying a first correction value to correct the air-fuel ratio when the output signal changes from a rich side to a lean side or vice versa with respect to a predetermined reference value, and integral control applying a second correction value to correct the air-fuel ratio whenever a predetermined period of time elapses so long as the output signal remains on the lean side or on the rich side with respect to the predetermined reference value. At least one of the first and second correction values is set to a smaller first value as load on the engine is higher, and the set at least one correction value is applied to correction of the air-fuel ratio in a direction of enriching the mixture.