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. 06, 1993
Filed:
Aug. 29, 1991
Honda Giken Kogyo Kabushiki Kaisha, Tokyo, JP;
Abstract
An air-fuel ratio feedback control method for an internal combustion engine having an exhaust gas ingredient concentration sensor arranged in the exhaust passage and having output characteristics in approximate proportion to the concentration of an ingredient in exhaust gases from the engine, wherein when the engine is in a predetermined operating condition, the air-fuel ratio of an air-fuel mixture supplied to the engine is feedback-controlled to a desired air-fuel ratio dependent on the predetermined operating condition of the engine, and when the engine is in a predetermined deceleration condition, the fuel supply to the engine is cut off. When the engine has shifted from an operating condition other than the predetermined deceleration condition to the predetermined deceleration condition, the desired air-fuel ratio is held at a value assumed immediately before the engine shifts from the operating condition other than the predetermined deceleration condition to the predetermined deceleration condition, for a predetermined time period after the shifting. The feedback control of the air-fuel ratio is started with the held value as an initial value of the desired air-fuel ratio when the engine has shifted to the predetermined operating condition. Preferably, the desired air-fuel ratio is held at a value substantially corresponding to a central value of air-fuel ratio after the predetermined time period has elapsed.