| 摘要 |
PROBLEM TO BE SOLVED: To provide the auxiliary air control device of an internal combustion engine which can reduce an intake sound. SOLUTION: A straightening vane 4 is united-formedly provided on the downstream side of an idle speed control valve 3 in an auxiliary air passage 2, and since its edge part is provided with a smooth R-shape, after passing through a valve body 3a, an intake air can be straightened to control turbulent flow energy. Thus force to vibrate a serge tank 6 installed on the downstream side is restrained to make a foreign sound generated there smaller. In addition, an enlarged passage chamber 5 where a sectional area to a flow direction is enlarged is formed on the downstream side of the straightening vane 4, and air flow speed is thereby eased in the enlarged passage chamber 5, and an intake sound can be further restrained. In addition, since the straightening vane 4 and the enlarged passage chamber 5 are unitedly formed with a throttle body 1, the assembly of parts and their maintenance are easier in comparison with a separated body, and moreover since the number of parts does not increase, rising in cost can be controlled. |
