Method and apparatus for controlling air-fuel ratio in internal combustion engine

Patent · Tue Dec 09 04:00:00 EST 1986

OSTI ID:7226259

Saito, K; Iwamoto, K; Egami, T; Saito, T; Matuyama, T

A method is described for controlling the air-fuel ratio in an internal combustion engine having a plurality of cylinders, comprising the steps of: calculating a base fuel amount in accordance with predetermined parameters of the engine; generating an air-fuel ratio signal of the engine; selecting a cylinder from the cylinders; sampling and holding the air-fuel ratio signal corresponding to the selected cylinder; calculating an air-fuel ratio feedback amount in accordance with the sampled and held air-fuel signal during a first predetermined engine state; adjusting the actual air-fuel ratio in accordance with the base fuel amount and the air-fuel ratio feedback amount; determining a cylinder on the leanest side by changing the selected cylinder during a second predetermined engine state; and setting the cylinder on the leanest side as the selected cylinder during a state other than the second predetermined engine state.

• Assignee: Nippon Soken, Inc., Nishio
• Patent Number(s): US 4627402
• OSTI ID: 7226259
• Country of Publication: United States
• Language: English

Related Subjects

33 ADVANCED PROPULSION SYSTEMS
330100* -- Internal Combustion Engines
COMBUSTION CONTROL
COMPUTER CALCULATIONS
COMPUTERIZED CONTROL SYSTEMS
CONTROL
CONTROL SYSTEMS
CYLINDERS
ENGINES
FEEDBACK
FUEL-AIR RATIO
HEAT ENGINES
INTERNAL COMBUSTION ENGINES
SIGNALS