| 摘要 |
PROBLEM TO BE SOLVED: To reduce a cooling loss in a compression self ignition engine.SOLUTION: A head-side recess 13a is formed at the central part of the lower surface of a cylinder head 13, while an outer peripheral part 13d is formed radially outside the head-side recess 13a. A crown surface of a piston 14 is configured such that a raised part 14a is formed at its central part, a squish generating part 14b is formed at a part corresponding to the outer peripheral part 13d, and an intermediate part 14c is formed between the raised part 14a and the squish generating part 14b. A fuel injection valve 17 injects fuel mist F to a part partitioned by the head-side recess 13a, the raised part 14a and the intermediate part 14c, in a combustion chamber 15. In a later phase of the compression stroke, a distance L1 from the central axis Y to the inner wall of the head-side recess 13a is set longer than a distance L2 from the central axis Y to the crown surface of the piston 14, regarding a direction orthogonal to the central axis Y of a nozzle opening 18. |
