| 摘要 |
PURPOSE:To improve volume efficiency of an internal-combustion engine by providing air passages having different length each other and a switch valve changing over respective air passages in correspondence with the rotating number of the internal-combustion engine without providing plural suction pipes of different length. CONSTITUTION:A valve 10 is forwarded by a spring 12 till an internal-combustion engine 11 attains a predetermined rotating number. And the air flowed from a suction port 3 is passing through a filter element 2 and fed to the internal-combustion engine 11 from an opening 7 through an air passage B and an exhaust port 9. While when the internal-combustion engine attains the predetermined rotating number, a valve 13 is opened by a control unit 14 and the valve 10 is retired by negative pressure of an intake manifold. Then, the air passage B is closed to open an air passage A. The air flowed from A is fed to the internal-combustion engine from the opening 8 through the exhaust port 9. This time, an opening 7 is always opened, so the volume held by the air passage B is utilized for sound arresting, attached function of an air cleaner. |
