INTERNAL COMBUSTION ENGINE

PROBLEM TO BE SOLVED: To further improve engine performance by turning air into a further clear tumble flow when turning the air sucked in a cylinder by passing through intake passages into the tumble flow. SOLUTION: A butterfly type throttle valve 17 is arranged in the intake passages 9 and 16. A midway part of the throttle valve 17 in the radial direction of the intake passages 9 and 16 is pivoted on a member forming the intake passages 9 and 16. This throttle valve 17 performs valve opening-closing operation when one end part side 20 of the throttle valve 17 reciprocatably rotates A and B toward the cylinder 2 side with its pivot axis 19 as the center. The cross-sectional center line 30 of a first part 29 of the intake passage 16 on the upstream side of the throttle valve 17, is deviated to the one end part side 20 of the throttle valve 17 in the radial direction of the intake passage 16 to the cross-sectional center line 32 of a second part 31 of the intake passage 16 adjacently arranged in this first part 29 on the downstream side of this first part 29. COPYRIGHT: (C)2007,JPO&INPIT