| 摘要 |
PURPOSE:To enable to change the supercharging pressure only by varying the opening of an accelerator, i.e., a throttle valve, by opening and closing a by-pass passage communicating an upper portion and a lower portion of a supercharger by a control valve which is operated in response to a signal pressure given from a port located on the downstream side of the throttle valve. CONSTITUTION:When the opening of a throttle valve 14 is small, negative pressure is acted in a carburetor port 23. Since the negative pressure is introduced into a signal chamber 20 of a control valve 18 via ports 23, 21, a diaphragm 19 is moved downward and a by-pass passage 16 is opened by a by-pass valve 17. Resultantly, intake air from an air cleaner is passed through the by-pass passage 16 by-passing a supercharger 10, so that the supercharging effect of the supercharger 10 is lowered. On the other hand, when the throttle valve 14 is opened to a position exceeding the carburetor port 23, atmospheric pressure is introduced into the signal chamber 20 and the diaphragm 19 is moved upward, so that the by-pass passage 16 is closed by the by-pass valve 17 and the intake air is supercharged by the supercharger 10. |
