| 摘要 |
PROBLEM TO BE SOLVED: To strengthen a tumble flow in a combustion chamber without complicating a configuration.SOLUTION: An intake port structure for an engine includes an intake port 5 connected to a combustion chamber 3 of the engine, and adapted to be opened/closed by an intake valve 6, and an annular seat ring 20 provided in a region of the intake port 5 facing the combustion chamber 3, the seat ring 20 including a valve abutting part 21 expanding from the corner side to the side of the combustion chamber for the intake valve 6 to abut thereon, and a throat part 22 provided on the further corner side than the valve abutting part 21, and expanding from the corner side to the side of the valve abutting part 21, where, eccentric relative to a center line p2 of a plan-view circular outer face 23 of the seat ring 20, a center line p1 of a similarly plan-view circular flow path inner face 24 is arranged on the side far from an axial core x of a cylinder bore. The throat part 22 is formed deeper into the corner side at the front end side close to the axial core x of the cylinder bore than at the rear end side far from the axial core x of the cylinder bore.SELECTED DRAWING: Figure 1 |
