Patent · US Expired

Device for reactivating catalyst of engine

US6178743A · kind A · utility

60Cited by
6References
22Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 31, 1998
Grant dateJan 30, 2001
Priority date
Expiry dateJul 31, 2018

Classification

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

Abstract

A catalyst is housed in a casing arranged in the exhaust passage of the engine. A pressure reducing valve, which is usually closed, is arranged in a bypass passage branching off from the exhaust passage upstream of the casing. The fuel injector usually injects fuel at the combustion stroke or the exhaust stroke to feed hydrocarbon, and NO.sub.X is reduced in the catalyst by the hydrocarbon. When the catalyst is judged to be poisoned, the timing of the secondary fuel injection is advanced with respect to the timing of the usual secondary fuel injection, and the pressure reducing valve is opened to reduce the pressure in the casing. In this way, the catalyst is reactivated.

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