Patent · US Expired

Air-fuel ratio control system for internal combustion engines

US5941224A · kind A · utility

0Cited by
5References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 29, 1997
Grant dateAug 24, 1999
Priority date
Expiry dateJul 29, 2017

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF02M25/08
  • WIPO fieldEngines, pumps, turbines
  • WIPO sectorMechanical engineering

Abstract

An air-fuel ratio control system for an internal combustion engine includes an air-fuel ratio sensor arranged in the exhaust system of the engine, for generating an output indicative of the air-fuel ratio of exhaust gases emitted from the engine. An ECU carries out feedback control of controlling the air-fuel ratio of a mixture supplied to the engine to a predetermined desired air-fuel ratio in response to the output from the air-fuel ratio sensor, by using at least one feedback control gain. A purge control valve purges evaporative fuel generated in the fuel tank to the engine. The at least one feedback control gain is set to a smaller value when the degree of influence of evaporative fuel purged by the purge control valve upon the air-fuel ratio of the mixture is larger, and set to a larger value when the degree of influence of the purged evaporative fuel upon the air-fuel ratio of the mixture is smaller.

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