| 摘要 |
PURPOSE:To prevent any drop in acceleratory responsiveness and starting characteristics at a driving range where the quantity of suction air is few, by passing the suction air through a supercharging cylinder at the driving range abundant in the suction air quantity, while feeding a combustion cylinder with the suction air without passing the supercharging cylinder any longer at the driving range small in the suction air. CONSTITUTION:In a state of engine driving so close to the opening or closing of a throttle valve 18, a supercharging control valve 24 in a suction passage 20 leading to a supercharged second cylinder 3 is closed. An air-fuel mixture out of a carburetor 17 is sucked directly into a first cylinder 2 and a third cylinder 4 without passing through the second cylinder 3. In a state that the throttle valve 18 nears to be fully opened or closed, the supercharging control valve 24 comes into a state of being close to full open or close. The air-fuel mixture out of the carburetor 17 is sucked in the second cylinder 3 and pressurized and fed to the first cylinder 2 and the third cylinder 4 by way of a discharge passage 25. |
