| 摘要 |
PROBLEM TO BE SOLVED: To reduce the number of part items, by making a throttle valve in concurrent use for a function of an air intake control valve. SOLUTION: A throttle valve 14 is arranged just in the upstream of a pair of intake air ports 6a, 6b, a throttle shaft 15 supporting the throttle valve 14 is arranged in a crossing direction relating to an axial line Lp connecting intake valves 8 arranged in both the intake air ports 6a, 6b. When the throttle valve 14 is small opened, suction air is guided to a side of a lower valve part 14a along a slope of a surface of the throttle valve 14, suction air accelerating a flow speed flows from an opening part in a side of the lower valve part 14a to a side of a suction port 6a opened to a side of the lower valve part 14a, and strong swirl flow is generated in a combustion chamber 5. When an opening of the throttle valve 14 is increased, by allowing the suction air to flow from both the lower valve part 14a and an upper valve part 14b, generation of the swirl flow is suppressed while decreasing air intake resistance, a suction air amount flowing in the combustion chamber 5 is increased.
|
