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.

Date of Patent:
Oct. 31, 1989

Filed:

Sep. 01, 1988
Applicant:
Inventors:

Kunio Noguchi, Wako, JP;

Yuzuru Koike, Wako, JP;

Kazushige Toshimits, Wako, JP;

Assignee:
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
F02M / ;
U.S. Cl.
CPC ...
123589 ; 123489 ;
Abstract

A method of controlling the air-fuel ratio of a mixture of fuel supplied to an internal combustion engine. Feedback control is effected to response to an output from an exhaust-gas concentration sensor to bring the air-fuel ratio to a predetermined value when the engine is in a predetermined medium-load operating region. It is determined whether or not the engine is in a predetermined high-load operating region in which the feedback control is interrupted for bringing the air-fuel ratio to a value smaller than the predetermined value, and whether or not the engine is in a predetermined low-load operating region in which the feedback control is interrupted for bringing the air-fuel ratio to a value larger than the predetermined value. The feedback control is effected even when the engine is in the predetermined low-load operating region, if the engine continually stayed over a first predetermined time period in the predetermined high-load operating region, and has shifted to the low-load operating region within a second predetermined time period after leaving the predetermined high-load operating region.


Find Patent Forward Citations

Loading…