Patent · US Expired

Air-fuel ratio control apparatus for internal combustion engine

US5406927A · kind A · utility

25Cited by
17References
9Claims
0Family size

Assignees

Inventors

Key dates

Filing dateJun 22, 1993
Grant dateApr 18, 1995
Priority date
Expiry dateJun 22, 2013

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF02D41/0042
  • WIPO fieldEngines, pumps, turbines
  • WIPO sectorMechanical engineering

Abstract

An air-fuel ratio control apparatus constructed, in an engine of a type storing evaporated fuel generated in a fuel tank in a canister and thereafter drawing off the evaporated fuel to an intake side of an engine through a bleedoff passage, so as to inhibit renewal of an air-fuel ratio learning value when the evaporated fuel concentration is at a predetermined value or higher in case of learning and renewal of an air-fuel ratio in order to make feedback control of the air-fuel ratio of an air-fuel mixture supplied to the engine. In an apparatus which adsorbs evaporated fuel generated in a fuel tank in a canister and purges the evaporated fuel adsorbed in the canister to an intake side of an internal combustion engine together with air through a purge valve, an air-fuel ratio learning value is renewed in accordance with a deviation between an air-fuel ratio feedback FAF value detected by an oxygen sensor and a FAFSM value obtained by smoothing the FAF value with a large smoothing constant. Further, renewal of the air-fuel ratio learning value is inhibited when the concentration of the evaporated fuel is high, and renewal of the air-fuel ratio learning value is executed even during p…

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