| 摘要 |
PURPOSE:To relieve the high pressure generated by quick closing of throttle valve or any failure in a waiste gate at the time of supercharge pressure control without provision of any special passage, by allowing a single step motor to switch the number of engine revolutions under idling and supercharge pressure control. CONSTITUTION:When supercharge pressure control is to be made, a solenoid valve 18 is closed, and the air stream passing through a throttle valve 4 passes partially through a fixed orifice 19 to diverge into two streams, P1 flowing to a control valve of the waste gate and P2 flowing to a variable orifice 20 to be adjusted by a step motor 2. During idling, this step motor 2 is operated to adjust the air stream P3 to be fed to a variable passage 17 through said variable orifice 20, and the above-mentioned solenoid valve 18 is opened to increase air supply to the engine. In case any reason closes the throttle valve abruptly, the above-mentioned solenoid valve 18 is opened so as to bypass the high pressure air generated between throttle valve 4 and compressor 6 to the upper stream side of the compressor 6. |
