| 摘要 |
PURPOSE:To reduce suction resistance caused by a valve shaft, by a method wherein a secondary throttle valve, which has a valve shaft positioned along the inner wall surface of a suction passage and swings within a suction passage through the valve shaft, is mounted to at least one of a plurality of suction passages communicated with a single combustion chamber. CONSTITUTION:Two suction ports 6 are formed in each cylinder head 2 of a 4- cylinder internal combustion engine, and are opened and closed by their respective individual suction valves. Each suction port 6 is communicated with a suction chamber 15 through a suction distributing pipe 14, and the amount of the air sucked is controlled by a primary throttle valve 17 located in an air introduction passage 16 connected to the suction chamber 15. A valve shaft 28 of a secondary throttle valve 25 for controlling velocity of flow is positioned along a flange part 12 formed at a juncture between a suction pipe 11 and the suction distributing pipe 14, and when the amount of the air sucked is increased, the secondary throttle valve 25 is swung within the suction passage 23 and is opened through a diaphragm actuator 35 with the aid of a control part 20 to which the detecting value of a detecting part 19 for the amount of the air sucked is inputted. |
