Patent · US Expired

Device for determining deterioration of a catalytic converter for an engine

US5303548A · kind A · utility

18Cited by
4References
18Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 6, 1992
Grant dateApr 19, 1994
Priority date
Expiry dateOct 6, 2012

Classification

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

Abstract

A device for determining deterioration of a catalytic converter for an engine equipped with a catalytic converter disposed in the exhaust passage and upstream and downstream air-fuel ratio sensors disposed in the exhaust passage upstream and downstream of the catalytic converter, respectively, wherein the device calculates the area surrounded by the output response curve of the downstream air-fuel ratio sensor and a predetermined reference value line, the device determining whether or not the catalyst is deteriorated in accordance with the area calculated when the output of downstream air-fuel ratio sensor stays on a rich side or lean side air-fuel ratio for more than a predetermined time during feedback control of air-fuel ratio by the output of upstream air-fuel ratio sensor.

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