| 摘要 |
PURPOSE:To improve the accelerating performance of an engine which is provided with a turbo-charger and has a turbine disposed at the lower side of the catalyst in an exhaust passage by feeding air into the upstream exhaust passage of the catalyst. CONSTITUTION:When a car which is running at a low speed is acceleratted, an air pump 9 is driven by an engine. A discharge pressure PA from an air pump 9 is low and another discharge pressure PB therefrom becomes the atmosphere pressure, since a throttle valve 8 is kept open, so that a regulation valve 23 is opened. Compressed air is then sent into an exhaust passage 2 and CO which is a chief composition of exhaust gas reacts to a catalyst 3 and oxidized, whereby increasing temperature at the inlet 7 of a turbine 4. Revolution of the turbine 4 will then be boosted so that the problem of turbo lag may be dissolved. This operation is completed within a short period (a few minutes) before completion of acceleration. Revolution of the air pump 9 is increased in accordance with increase in engine speed. The resultant increase in discharged pressure PA will act on pressure in a pressure chamber 17. A regulation valve 14 is then closed to interrupt supply of air, whereby restraining increase in pressure at the inlet of the turbine. |
