EXHAUST EMISSION CONTROL DEVICE FOR INTERNAL COMBUSTION ENGINE

摘要

PROBLEM TO BE SOLVED: To improve an effect of an exhaust emission control device by adding a means to control pressure of exhaust gas to be introduced to a filter to the exhaust emission control device devised to alternately change the exhaust gas upstream and the downstream to each other to pass exhaust gas by a change- over valve to the filter with a catalyst. SOLUTION: This exhaust emission control device is furnished with the filter 22 bearing active oxygen releasing mediums 60, 61 and free to temporarily capture fine particulates 62 in exhaust gas, an exhaust gas change-over means 71 to alternately change a first flow to make exhaust gas flow from one side of the filter and a second flow to make exhaust gas flow from the other side of the filter to each other and a pressure releasing means 710 to release pressure of exhaust gas at the time when pressure of the exhaust gas introduced to the filter 22 is higher than a set value.