Patent · US Expired

Exhaust purification device of internal combustion engine

US5473890A · kind A · utility

109Cited by
8References
37Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 29, 1994
Grant dateDec 12, 1995
Priority date
Expiry dateJul 29, 2014

Classification

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

Abstract

An NO.sub.x absorbent (19) which absorbs NO.sub.x when an air-fuel ratio of an inflowing exhaust gas is lean, while releases the absorbed NO.sub.x when lowering an oxygen concentration in the inflowing exhaust gas, is arranged in an exhaust passage of an internal combustion engine. An SO.sub.x absorbent (18) which absorbs SO.sub.x when the air-fuel ratio of the inflowing exhaust gas is lean, while releases the absorbed SO.sub.x when the air-fuel ratio of the inflowing exhaust gas is made rich is arranged in the exhaust passage on the upstream side of the NO.sub.x absorbent (19). When the lean air-fuel mixture is burned, the SO.sub.x is absorbed into the SO.sub.x absorbent (18) and, at the same time, the NO.sub.x is absorbed into the NO.sub.x absorbent (19), and when the air-fuel ratio of the air-fuel mixture is switched from lean to rich, SO.sub.x is released from the SO.sub.x absorbent (18), and NO.sub.x is released from the SO.sub.x absorbent (19 ).

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