摘要 |
In a hybrid vehicle equipped with an exhaust gas purifying apparatus, when a gasoline engine stops, an exhaust gas passage is closed by a pair of upstream-side and downstream-side throttle units to form an accommodation space. A pressure reduction unit reduces a pressure of the closed accommodation space where a three way catalyst is placed. The exhaust gas around the three way catalyst in the closed accommodation space does not leak into either an outside atmosphere side or into the gasoline engine side. Reducing the pressure in the closed accommodation space decreases heat conduction through the exhaust gas toward the outside. It is thereby possible to prevent the temperature drop of the three way catalyst and to keep the three way catalyst at a temperature of not less than its activation temperature for a long period of time even if the gasoline engine stops.
|