| 摘要 |
PURPOSE:To decrease combustion pressure of an engine at idling operation and reduce a level of noise, by providing an air throttle plate in an air passage at the upstream side of a compressor, turning said throttle plate to the closing direction at idling time and reducing a suction flow amount. CONSTITUTION:A throttle plate 37 is rotatably provided in an air passage 36 in the upstream side of a compressor wheel 18 of a turbocharger 10 and operated by a servo means 44 through a rod 50. The sevo means 44 is operated by negative pressure from a negative pressure tank 42 guided through a passage 43 to a negative pressure chamber 48, and the passage 43 is conducted by opening a solenoid valve 62 at closing of a normally-open switch 61 when an accelerator pedal is depressed. The throttle plate 37 is normally placed in a position as shown by a full line in the drawing, if the accelerator pedal is depressed at constant speed running operation or the like when increase of an air flow amount is required, the throttle plate 37 is turned to a position of broken line by the servo means 44. |
