| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a deterioration determining device for exhaust gas purifying apparatus, determining accurately and promptly deterioration of an NOx purifying catalyst. <P>SOLUTION: A deterioration determinig device 1 of an exhaust gas purifying apparatus 10 for determining deterioration of the NOx purifying catalyst 11 includes an ECU 2. The ECU 2 executes a high NOx concentration control when determinig deterioration (step 5), calculates NOx supply amount sumPreNOx based on an upstream side NOx concentration CNOx_Pre detected during the high NOx concentration control (step 32), calculates NOx slip amount sumPostNOx, based on a downstream side NOx concentration CNOx_Post detected during the high NOx concentration control (step 33), and determines that the NOx purifying catalyst 11 has deteriorated, when sumPostNOx>NOxJUD holds true, in the case where sumPreNOx>NOxREF holds true (steps 34, 50, 52). <P>COPYRIGHT: (C)2010,JPO&INPIT</p> |
