| 摘要 |
PURPOSE:To provide strong swirl in a combustion cylinder, by introducing a part of compressed air in a supercharging cylinder to a suction port in the combustion cylinder at a low load area without supplying fuel. CONSTITUTION:Pressurized air sucked from an air cleaner 19 to the second cylinder 3 and compressed therein is alternately sucked into the first cylinder 2 and the third cylinder 4. When an opening degree of a throttle valve 23 in a carburetor 24 is large, pressure differential across the throttle valve 23 is small, and accordingly pressurized air in a surge tank 21 is almost never discharged from discharge ports 17 and 18. On the other hand, when the opening degree of the throttle valve 23 is small, the pressure differential across the valve 23 is large, and accordingly a part of the pressurized air in the surge tank 21 is discharged through the discharged ports 17 and 18 to intake manifolds 7 and 8 without being passed through the carburetor 24. |
