Patent · US Expired

Rapid catalyst warm-up control device for internal combustion engine

US7047727B2 · kind B2 · utility

9Cited by
8References
10Claims
0Family size

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Key dates

Filing dateMay 26, 2004
Grant dateMay 23, 2006
Priority date
Expiry dateMay 26, 2024

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02T10/12
  • WIPO fieldEngines, pumps, turbines
  • WIPO sectorMechanical engineering

Abstract

A rapid catalyst warm-up control device for an internal combustion engine performs irregular injection dither control during the rapid catalyst warm-up control after starting the engine. In the irregular injection dither control, injection modes are switched after every fuel injection to the cylinders (every 180° CA for a 4-cylinder engine) between a lean injection mode and a rich injection mode in such a pattern that rich injections will not occur consecutively for the same cylinder (dither cycle=540° CA, 900° CA, 1080° CA, or the like). In the lean injection mode, fuel is injected such that the air-fuel ratio is leaner than the stoichiometric ratio, and in the rich injection mode, air-fuel ratio is richer than the stoichiometric ratio. The rich gas emitted from the cylinders where the rich injection has been performed is thus allowed to flow through a different catalyst region every time instead of flowing only through the same region.

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