| 摘要 |
A cylinder head of an internal combustion engine is formed with concavity. Two flat protruded portions are formed on the spherical surface of the concavity and their planes intersect each other at a location slightly below the vertex of the spherical surface. At the two flat protruded portions, intake and exhaust valve seats are disposed. A combustion chamber is defined by the spherical surface, the surfaces of the flat protruded portions and the piston crown. |
