Patent · US Expired

Exhaust purification apparatus for internal combustion engine

US7032374B2 · kind B2 · utility

7Cited by
9References
16Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 2, 2004
Grant dateApr 25, 2006
Priority date
Expiry dateMar 10, 2024

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02T10/12
  • WIPO fieldEngines, pumps, turbines
  • WIPO sectorMechanical engineering

Abstract

An exhaust purification apparatus for an internal combustion engine includes a catalyst unit disposed in an exhaust passage of the engine, upstream and downstream air-fuel-ratio sensors disposed upstream and downstream, respectively, of the catalyst unit, a main-feedback controller, and a sub-feedback controller. The main-feedback controller calculates a main-feedback control quantity on the basis of an output value of the upstream air-fuel-ratio sensor and a predetermined upstream-side target value, and corrects, on the basis of the main-feedback control quantity, the quantity of fuel injected by an fuel injector. The sub-feedback controller calculates a sub-feedback control quantity on the basis of an output value of the downstream air-fuel-ratio sensor and a predetermined downstream-side target value, and corrects, on the basis of the sub-feedback control quantity, the quantity of fuel injected by the fuel injector, independently of the correction of the fuel injection quantity by the main-feedback control means.

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