| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an exhaust emission control device enabling a reduction in the number of operations of a flow control means for controlling the flow of the exhaust gas flowing through a bypass passage for guiding the exhaust gas to a downstream side catalyst by bypassing the upstream catalyst. <P>SOLUTION: This exhaust emission control device comprises: an upstream side catalyst 5 and the downstream side catalyst 8 for controlling the exhaust gas of an internal combustion engine 1; the bypass passage 4 for guiding the exhaust gas by bypassing the upstream side catalyst; a flow control means 6 for controlling the flow of the exhaust gas through the bypass passage; and a return determination means 20 for returning the device from the bypass control for flowing the exhaust gas into the bypass passage according to the internal combustion engine operating information affecting the temperature of the upstream side catalyst. The exhaust emission control device comprises a gradient detection means 10 for detecting the gradient of a traveling path. When a rising gradient is detected, the return determination means does not return the device from the bypass control until the internal combustion engine operating information becomes such a value that the temperature of the upstream side catalyst becomes further low as compared with a case in which the rising gradient is not detected. <P>COPYRIGHT: (C)2009,JPO&INPIT |
