Patent · US Expired

Exhaust gas purifying apparatus and method for internal combustion engine

US7555895B2 · kind B2 · utility

6Cited by
22References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 19, 2004
Grant dateJul 7, 2009
Priority date
Expiry dateDec 20, 2024

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02T10/40
  • WIPO fieldEngines, pumps, turbines
  • WIPO sectorMechanical engineering

Abstract

In exhaust gas purifying apparatus and method for an internal combustion engine, an abnormality determination of an NOx (Nitrogen Oxides) removing catalyst is executed on the basis of output values of both of a first exhaust gas atmosphere detecting section and a second exhaust gas atmosphere detecting section (for example, oxygen concentration sensors interposed in an exhaust passage of the engine between inlet and outlet portions of the NOx removing catalyst) from a time at which an output value of the first exhaust gas atmosphere detecting section is varied to a first predetermined value to a time at which the output value of the second exhaust gas atmosphere detecting section is reached to a second predetermined value when an exhaust gas atmosphere varying section (control unit) increases the ratio of a reducing agent in the exhaust gas.

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