| 摘要 |
PROBLEM TO BE SOLVED: To provide structure of a combustion chamber of a spark-ignition engine in which a compression ratio is practically effectively improved. SOLUTION: A spark-ignition engine has: the combustion chamber 14 formed between a lower face 11 of a cylinder head and a piston top face 4, in which the cylinder head lower face 11 functions as a ceiling wall thereof; and an ignition plug 15 whose tip faces the inside of the combustion chamber 14 from the ceiling wall 11. With a state where a piston 13 is at a top dead center, a main part of a space in the combustion chamber is formed by a first combustion space 14a around the ignition plug 15 and a second combustion space 14b of a cylinder bore peripheral part, the first combustion space 14a communicates with the second combustion space 14b through a small gap part 5 formed by narrowing a clearance between the piston top face 4 and the ceiling wall 11. COPYRIGHT: (C)2007,JPO&INPIT |
