INTERNAL COMBUSTION ENGINE HAVING COMBUSTION CHAMBER WITH BLENDED HEMISPHERICAL AND PENT-ROOF PORTIONS

摘要

An internal combustion engine is provided including an engine block (2), a cylinder head (12) mounted on the engine block (2) including a combustion face (13) forming a portion of a combustion chamber (3), wherein the combustion face (13) includes a pent-roof portion (14) and a hemispherical shaped portion (16). A first intake valve port formed in the cylinder head (12) includes a first intake valve port opening (29) formed in the pent-roof portion (14) while a second intake valve port formed in the cylinder head (12) includes a second intake valve port opening (32) formed in the pent-roof portion (14). An exhaust valve port formed in the cylinder head (12) includes an exhaust valve port opening (32) formed in the hemispherical shaped portion (16). A transition portion (17) may also be included to blend the combustion face (13) connecting the pent-roof and the hemispherical portions. One or more spark plug bore openings (26,28) are formed and optimally positioned in the combustion face (13).