| 摘要 |
PROBLEM TO BE SOLVED: To provide a variable intake passage causing charging efficiency of an internal combustion engine to be improved.SOLUTION: A variable intake passage comprises an intake control box 3 and an intake control valve 4 at an inlet thereof upstream of a throttle valve 2 in an intake passage 11 of an internal combustion engine. The intake control box has a cross-sectional area that is from 8 to 10 times a cross-sectional area of the intake passage 11, and has a cylindrical shape or a rectangular parallelepiped shape having a volume that is from 120 to 200% of the total displacement. The intake control valve is controlled to be opened and closed by an ECU or a damper to control a clearance to the intake passage 10. A flow velocity and inertia of an intake at the inlet of the intake control box is increased as compared with an outlet to generate check valve effect in the intake control box, and the charging efficiency is thereby improved. |
