Patent · US Expired

Air-fuel ratio controller and method of controlling air-fuel ratio

US6314724A · kind A · utility

31Cited by
13References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 20, 2000
Grant dateNov 13, 2001
Priority date
Expiry dateNov 20, 2020

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF02D2200/501
  • WIPO fieldEngines, pumps, turbines
  • WIPO sectorMechanical engineering

Abstract

An air-fuel ratio controller for an internal combustion engine with a catalytic converter in an exhaust passage has an air-fuel ratio sensor, an engine sensor, and a control unit. The air-fuel ratio sensor produces a signal indicative of an air-fuel ratio of an exhaust gas in the exhaust passage on an upstream side of the catalytic converter. The engine sensor produces a signal indicative of misfiring of the engine. The control unit is operatively coupled to the air-fuel ratio sensor and the engine sensor. The control unit computes an estimated quantity of oxygen to be stored in the catalytic converter based on the signal from the air-fuel ratio sensor, and determines if the engine is misfiring based on the signal from the engine sensor. The control unit also produces an estimated adjustment value and adjusts an air-fuel ratio of intake air based on the estimated adjustment value such that the estimated quantity of oxygen to be stored substantially coincides with a predetermined target quantity of oxygen to be stored. However, when misfiring is determined based on the signal from the engine sensor, the computation of the estimated quantity of oxygen to be stored is stopped or not u…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.