Diagnosis method for an exhaust gas post-treatment system
US8286417B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 19, 2006 |
| Grant date | Oct 16, 2012 |
| Priority date | — |
| Expiry date | Feb 28, 2030 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/40
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
The invention relates to a diagnosis method for an exhaust gas post-treatment system for the reduction of nitric oxides in the exhaust gas train of an internal combustion engine by means of selective catalytic reduction. The following steps are provided for easy recognition of errors: definition of at least one threshold value for the Nox concentration for at least one engine operation point; shifting the operational mode of the internal combustion engine into an operational state of diagnosis, wherein in the operational state of diagnosis substantially more Nox emissions are produced than in the normal operational mode; determining an amount of reducing agents corresponding to the increased amount of Nox emisions in the operational state of diagnosis; controlling a dosing device in order to introduce the amount of reducing agents, corresponding to the increased amount of NOx emissions during the operational state of diagnosis, into the wase gas; measuring the concentration of NOx downstream from the post-treatment device; comparing the measured concentration of NOx to the threshold value; taking a decision as to the erroneous or error-free operation of the waste gas post-treatment…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.