| 摘要 |
<p>PURPOSE:To aim at improving the fuel consumption and exhaust gas properties of an engine, by using both flap for adjusting the flow rate of exhaust gas at the inlet of an exhaust turbine and bypass valve disposed in a passage bypassing the exhaust turbine, and as well by increasing the opening degree of the bypass valve when an abnormality of the flap is detected. CONSTITUTION:A flap at the inlet of an exhaust turbine is set at an optimum position in accordance with the amount of intake-air and the rotational speed of an engine which are detected by a means for detecting the operating condition of the engine. Further the amount of exhaust gas which bypasses the exhaust turbine is controlled by a bypass valve controlling means. When a means for detecting an abnormality of the flap detects an abnormality of the flap, a bypass compensating means increases the opening degree of the bypass valve to discharge a part of exhaust gas to the outside by way of a bypass passage without letting the same flow through the flap and the exhaust turbine, thereby it is possible to prevent the pressure of exhaust gas upstream of the flap from excessively rising.</p> |
