| 摘要 |
<p>PURPOSE:To transfter an operation point of a compressor from a noise generation range by opening a passage which bypasses the compressor of a supercharger when intake air flow quantity and supercharging pressure are respectively, in a specified range so as to circulate compressed air to the entrance side of the compressor. CONSTITUTION:An engine 1 has a turbine provided at an exhaust passage which is not shown, a compressor 4b provided at an intake passage 2, and a turbocharger 4 consisting of a shaft 4c which connects them. On an intake relief passage 10 which bypasses the compressor 4b, an intake relief valve 11 is arranged. In this case, when intake air flow quantity detected by means 25, 31 and supercharging pressure are in specified range, respectively, a solenoid valve 12 is switchably controlled ON by a control unit 35 so as to introduce atmospheric air to a downstream pressure chamber 21c of an actuator 21. Consequently, the intake relief valve 11 is opened so as to introduce the compressed air to the entrance of the compressor 4b.</p> |
