Patent · US Active

Air-fuel ratio controller for internal combustion engine

US7356985B2 · kind B2 · utility

9Cited by
5References
18Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 11, 2006
Grant dateApr 15, 2008
Priority date
Expiry dateJul 11, 2026

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF02D2041/1419
  • WIPO fieldEngines, pumps, turbines
  • WIPO sectorMechanical engineering

Abstract

A target air-fuel ratio setting part has a sub-feedback part, a target air-fuel ratio enriching part, and a target air-fuel ratio changeover part. The sub-feedback part variably sets a target air-fuel ratio upstream of a catalyst on the basis of a detection signal of an O2 sensor provided downstream of the catalyst. The target air-fuel ratio changeover part uses, as the target air-fuel ratio, a rich target air-fuel ratio which is set by the target air-fuel ratio enriching part on conditions such that the target air-fuel ratio set by the sub-feedback part is rich. A cylinder-by-cylinder air-fuel ratio estimation part calculates a cylinder-by-cylinder air-fuel ratio on the basis of a detection value of an air-fuel ratio sensor and the target air-fuel ratio.

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