Patent · US Active

Exhaust gas purification system of an internal combustion engine

US8375706B2 · kind B2 · utility

2Cited by
7References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 18, 2008
Grant dateFeb 19, 2013
Priority date
Expiry dateMay 12, 2029

Classification

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

Abstract

A technique is provided which is capable of completing SOx poisoning recovery control on a NOx storage reduction catalyst in a shorter period of time. In the course of the SOx poisoning recovery control, the degree of decrease of a SOx release speed resulting from a decrease in an amount of SOx occlusion of the NOx catalyst (the degree of decrease of the SOx release speed (Ddw)) with respect to that at the time of start of the SOx poisoning recovery control is estimated. In accordance with the increasing degree of decrease of the SOx release speed (Ddw), a catalyst bed temperature (Tc) is caused to rise up to a higher side target temperature (Tct), and at the same time an exhaust gas air fuel ratio (A/F) is caused to lower up to a richer side target air fuel ratio (A/Ft), whereby the SOx release speed Vsox during the SOx poisoning recovery control is suppressed from lowering.

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