| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an exhaust emission control device for an internal-combustion engine, capable of suppressing the deterioration of fuel economy, while preventing the deterioration of emission. <P>SOLUTION: The exhaust emission control device of an internal-combustion engine includes an engine, a catalyst, a recirculation passage, a fuel addition valve, a pump, a NOx reduction control means and an EGR control means. The catalyst is a so-called NOx reduction storage catalyst. The NOx reduction control means performs the NOx reduction of a catalyst by controlling the pump and a fuel addition valve, while the engine stops. The EGR control means adjusts the air-fuel ratio of combustion to a lean atmosphere by performing EGR control at a lower EGR rate than a usual EGR rate when the engine is activated. The EGR control means performs EGR control at the usual EGR rate again when a NOx storage amount of a catalyst reaches a saturated amount. <P>COPYRIGHT: (C)2010,JPO&INPIT |
