| 摘要 |
<p>PURPOSE:To prevent bad smell of catalyzer for an automobile due to sulfur compounds by raising the temperature of catalyzer higher than 500 deg.C during warming up running of the engine whereafter the engine is immediately brought into idling and by restraining supply of secondary air. CONSTITUTION:Conventionally, while waiting a change of a traffic signal and so on, an automobile provided with catalyzer has emitted bad smell due to hydrogen sulfide or carbonyl sulfide adhering to the catalyzer. In order to prevent this, according to the present invention, the temperature of the catalyzer bed is raised higher than 500 deg.C by warming up running of the engine, and the engine is brought into idling immediately after the warming up running. Besides, the amount of secondary air supply to the catalyzer thereupon is limited to control air fuel ratio of exhaust gas near to an entrace of the catalyzer lower than 15. By this operation, sulfer compounds adhering to the catalyzer are gradually removed, and bad smell from the catalyzer can be prevented by maintaining this idling condition longer than 20min.</p> |
