Exhaust emission control device for internal combustion engine
Number of patents in Portfolio can not be more than 2000
United States of America Patent
Stats
-
Nov 26, 2002
Grant Date -
May 9, 2002
app pub date -
May 26, 2000
filing date -
Jun 3, 1999
priority date (Note) -
Expired
status (Latency Note)
Importance
Abstract
An object of the invention is to reliably judge if a NO.sub.X absorbent has deteriorated due to sulfur poisoning, or has heat deteriorated. At the time of executing rich spiking, a sulfur poisoning stoichiometric conversion time threshold value tm: LMT-S deterioration, for judging if a NO.sub.X absorbent has been sulfur poisoned, and a heat deterioration stoichiometric conversion time threshold value tm: LMT heat deterioration, for judging if the NO.sub.X absorbent has heat deteriorated to an extent that the NO.sub.X absorption capacity has been lost, are set in relation to the time (stoichiometric conversion time) taken for an output signal from a second O.sub.2 sensor to change from lean to rich. When a measurement value of the stoichiometric conversion time is shorter than the heat deterioration stoichiometric conversion time threshold value tm: LMT heat deterioration, it is judged that the NO.sub.X absorbent has completely heat deteriorated, and when this is longer than the heat deterioration stoichiometric conversion time threshold value tm: LMT heat deterioration, and shorter than the sulfur poisoning stoichiometric conversion time threshold value tm: LMT-S deterioration, it is judged that there is sulfur poisoning.
First Claim
Family
International Classification(s)
Cited Art Landscape
Patent Citation Ranking
Advertisement
Advertisement
Advertisement
Recipient Email Address
Recipient Email Address
Comment
Recipient Email Address
Add to Portfolio(s)
To add this patent to one, or more, of your portfolios, simply click the add button.
This Patent is in these Portfolios:
Add to additional portfolios:
Last Refreshed On:
Changes done successfully