| 摘要 |
<P>PROBLEM TO BE SOLVED: To quickly raise a temperature of a reduction catalyst and early start injection control of a reduction agent by switching a flowing direction of exhaust gas from a normal direction to a reverse direction, when the temperature of the exhaust gas is raised while the temperature of the reduction catalyst becomes less than a reference temperature and the injection control of the reduction agent is stopped. <P>SOLUTION: This exhaust emission control device includes exhaust gas flow path switch means for switching a flowing direction of exhaust gas to a normal direction directing to a reduction catalyst from a particulate filter or a reverse direction directing to the particulate filter from the reduction catalyst. The device includes a control device including a reduction agent injection control part for controlling injection of the reduction agent from a reduction agent supplying part while the temperature of the reduction catalyst is not less than a predetermined temperature, and a control part of the exhaust gas flow path switch means for controlling the exhaust gas flow path switch means so that the flowing direction of the exhaust gas becomes a reverse direction when the temperature of the reduction catalyst is less than a predetermined temperature and the temperature of the exhaust gas is determined as raising. <P>COPYRIGHT: (C)2009,JPO&INPIT |
