| 摘要 |
<p>PURPOSE:To increase the torque of an engine in the range of medium speed, by providing a means for judging on the basis of the running condition of the engine whether supercharging pressure should be limited to a set level or not, and by keeping a by-pass closed when it is judged near an interception point that the supercharging pressure should not be limited to the set level. CONSTITUTION:A control unit 22 receives signals S1, S2 from a rotational frequency sensor 23 and a knock sensor 24. When an engine is run in the range of medium speed under low load without knocking, it is judged by a judgment means 25 that the supercharging pressure for an intake should not be limited to a set level, so that a solenoid valve 21 is supplied with electricity. At that time, a swing valve 7 closes a by-pass 6 to apply all the energy of exhaust gas to a turbine 3. Even if the supercharging pressure exceeds the set level, the by-pass 6 is closed until the rotational frequency of the engine exceeds a prescribed level or the engine knocks.</p> |
