Patent · US Expired

Exhaust gas recirculation system abnormality diagnosis device

US7251555B2 · kind B2 · utility

6Cited by
2References
17Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMar 2, 2006
Grant dateJul 31, 2007
Priority date
Expiry dateMar 16, 2026

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF02M2026/003
  • WIPO fieldEngines, pumps, turbines
  • WIPO sectorMechanical engineering

Abstract

An exhaust gas recirculation passage connects an exhaust passage with an intake passage. A cooling device is mounted to the exhaust gas recirculation passage for cooling exhaust gas in the exhaust gas recirculation passage. An EGR valve adjusts a flow passage area of the exhaust gas recirculation passage. An exhaust gas quantity (EGR quantity) in the exhaust gas recirculation passage is feedback-controlled by manipulating an opening degree of the EGR valve based on a measurement value of an airflow meter. Existence or nonexistence of an abnormality in the cooling device is diagnosed based on whether a measurement value of the opening degree of the EGR valve contains a component corresponding to compensation for reduction of the EGR quantity due to degradation of cooling performance of the cooling device.

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