Air/fuel ratio feedback control system for internal combustion engine
Number of patents in Portfolio can not be more than 2000
United States of America Patent
Stats
-
Jul 13, 1993
Grant Date -
N/A
app pub date -
Oct 18, 1990
filing date -
Oct 18, 1989
priority date (Note) -
Expired
status (Latency Note)
Importance
Abstract
An air/fuel ratio feedback control system for an internal combustion engine sets an air/fuel ratio feedback correction coefficient on the basis of an air/fuel ratio for an air/fuel mixture introduced into a combustion chamber of the engine, to cause the air/fuel ratio to approach a set point thereof. The correction coefficient consists of a rich control proportional component P.sub.R, a lean control proportional component P.sub.L and an integral component I. When the air/fuel ratio set by the feedback control system deviates from an initial set point (the stoichiometric value) due to deterioration of an oxygen sensor for detecting the air/fuel ratio, the feedback control system compensates for the deviation to cause the air/fuel ratio to approach the initial set point, by varying a ratio of the rich control proportional component P.sub.R to the lean control proportional component P.sub.L in accordance with magnitudes of rich and lean detection levels, or by correcting a balance between the rich and lean control proportional components P.sub.R and P.sub.L on the basis of a relationship between signal level varying speeds of the proportional components P.sub.R and P.sub.L, a relationship between rich and lean control times, a relationship between rich and lean detection levels or the like.
First Claim
Family
International Classification(s)
Cited Art Landscape
Patent Citation Ranking
Recipient Email Address
Recipient Email Address
Comment
Recipient Email Address
Add to Portfolio(s)
To add this patent to one, or more, of your portfolios, simply click the add button.
This Patent is in these Portfolios:
Add to additional portfolios:
Last Refreshed On:
Changes done successfully