| 摘要 |
An exhaust emission control device includes an adsorbent trapper having an adsorbent for adsorbing and desorbing hydrocarbon in exhaust gas, a catalytic converter, a main exhaust gas passage with a first valve, a bypass exhaust gas passage with a second valve and a control unit. The bypass exhaust gas passage bypassing the first valve is connected with the adsorbent. The control unit controls the first and second valves to desorb the hydrocarbon from the adsorbent when a condition is satisfied. The condition is that the catalyst converter is in active, an oxygen adsorption amount of the catalyst converter is not less than a first predetermined amount and an exhaust gas amount is not more than a second predetermined amount. The first valve is opened and the second valve is closed when the condition is not satisfied during desorption of the hydrocarbon from the adsorbent. |
