| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an exhaust emission control device for maintaining a catalyst at the active temperature over a long period, by reducing conduction of heat to the internal combustion engine side from the catalyst. <P>SOLUTION: When a gasoline engine 11 stops operation, an exhaust passage 21 is closed by an upstream side orifice part 30 and a downstream side orifice part 40. A storage space 26 for storing a three-way catalyst 24 by the upstream side orifice part 30 and the downstream side orifice part 40, is reduced in pressure by a pressure reducing pat 50. By storing the three-way catalyst 24 in the storage space 26, exhaust gas remaining around the three-way catalyst 24 does not flow out to any of the atmospheric side and the engine body 14 side. The movement of the heat with the exhaust heat as a heating medium is reduced by reducing pressure in the storage space 26. Thus, the temperature of the three-way catalyst 24 hardly drops. As a result, the movement of the heat by the exhaust gas is reduced, and a temperature drop in the three-way catalyst 24 is reduced. <P>COPYRIGHT: (C)2009,JPO&INPIT |
