Patent · US Expired

Diagnosing system and method of catalytic converter for controlling exhaust gas of internal combustion engine

US5758491A · kind A · utility

18Cited by
8References
39Claims
0Family size

Assignees

Inventors

Key dates

Filing dateMay 22, 1996
Grant dateJun 2, 1998
Priority date
Expiry dateMay 22, 2016

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02T10/40
  • WIPO fieldEnvironmental technology
  • WIPO sectorChemistry

Abstract

A diagnosing system of a catalytic converter in an internal combustion engine has a detecting unit to detect an operating state of the engine and an air/fuel ratio control unit to adjust a fuel injection amount so as to keep an air/fuel ratio of a mixture that is inhaled into the engine to a target value. The operating state of the engine is detected, whereby it is confirmed that the engine lies in a predetermined operating region to execute a catalyst diagnosis on the basis of the detected operating state. In each of a plurality of different catalyst diagnosis regions, the performance of the catalytic converter or the performance of the catalytic converter array is diagnosed on the basis of the output signal of the first exhaust gas component sensor arranged on the upstream side of the catalytic converter array and the output signal of the second exhaust gas component sensor arranged on the downstream side.

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