公开(公告)号：US06629408B1

公开(公告)日：2003-10-07

申请号：US09685571

申请日：2000-10-11

申请人： Akira Murakami ,  Mistuo Hashizume ,  Kotaro Miyashita ,  Toshikatsu Takanohashi ,  Yuichiro Tanabe ,  Akira Hashimoto

发明人： Akira Murakami ,  Mistuo Hashizume ,  Kotaro Miyashita ,  Toshikatsu Takanohashi ,  Yuichiro Tanabe ,  Akira Hashimoto

IPC分类号： F01N300

CPC分类号： F01N3/0842 ,  F01N11/007 ,  F01N2550/03 ,  F01N2570/04 ,  F01N2900/0422 ,  F02D41/028 ,  Y02T10/47

摘要： An exhaust emission control system for an internal combustion engine, having a nitrogen oxide removing device provided in an exhaust system of the internal combustion engine for absorbing nitrogen oxides contained in exhaust gases in an exhaust lean condition. The exhaust emission control system includes first and second oxygen concentration sensors respectively provided upstream and downstream of the nitrogen oxide removing device for detecting an oxygen concentration in the exhaust gases. The air-fuel ratio of an air-fuel mixture to be supplied to the engine is changed from a lean region to a rich region with respect to a stoichiometric ratio. An amount of reducing components flowing into the nitrogen oxide removing device from the time when an output value from the first oxygen concentration sensor has changed to a value indicative of a rich air-fuel ratio after enrichment of the air-fuel ratio is calculated. Deterioration of the nitrogen oxide removing device is determined according to the calculated amount of reducing components and an output value from the second oxygen concentration sensor.

摘要翻译： 一种用于内燃机的排气排放控制系统，其具有设置在内燃机的排气系统中的氮氧化物去除装置，用于吸收排气贫化状态下的废气中所含的氮氧化物。 废气排放控制系统包括分别设置在氮氧化物去除装置的上游和下游的用于检测废气中的氧浓度的第一和第二氧浓度传感器。 供给到发动机的空气燃料混合物的空燃比相对于化学计量比从贫区变为浓区。 计算从第一氧浓度传感器的输出值变为表示浓缩空燃比后的浓空燃比的值时流入氮氧化物除去装置的还原成分的量。 根据计算出的还原成分量和来自第二氧浓度传感器的输出值，确定氮氧化物除去装置的劣化。