| 摘要 |
PURPOSE:To improve combustion performance of a 4-cycle engine, by sufficiently stirring and mixing the fuel, wherein, intake air, sucked through an intake port, is caused to swirl in a combustion chamber. CONSTITUTION:During lowering of a piston, after the most of intake air flowing through an air intake passage 10 is guided, as shown by A, by a main flow guide piece 13 and is caused to swirl within a swirl generating chamber 11, then flows in a combustion chamber 5 through an intake air port 12. The rest intake air is guided by a splitting guide surface 14, and flows in a combustion chamber 5 through an intake air outlet 12 from a space on the inverted flow side of the swirl generating chamber 11 as shown by B. Intake air B guided by the splitting guide surface 14 exerts a rotational moment on a main flow A, and the main flow, sucked into the combustion chamber 5, forms a tornado-shaped swirl within the combustion chamber 5. This enables powerful stirring and mixing of the fuel within the combustion chamber 5. |
