| 摘要 |
PURPOSE:To enhance the charging efficiency of air fuel mixture gas in an internal combustion engine at low speed time by providing second throttle valve and a sub air intake passage at the air intake passage at the downsteam side of the throttle valve and introducing the mixture gas from the sub air intake passage into a combustion chamber to thereby take place turbulence flow state. CONSTITUTION:There are arranged a throttle valve 12 and second throttle valve 14 at an air intake passage 5 and a sub air intake passage 15 for communicating with the upstream and downstream of the valve 14 thereat. The outlet opening 17 of the passage 15 is extended along the axis of an air intake valve 6 to direct the air fuel mixture gas supplied from the opening 17 toward the mixture gas combustion chamber 4. Further, a vacuum diaphragm unit 20 for driving by means of vacuum in an air intake mainfold to be introduced from a vacuum tube 26 is connected to the valve 14, which is directed to closing operation at low speed time of the engine. The mixture gas is supplied through the passage 15 into the chamber 4. |
