| 摘要 |
<p>A diesel engine (1) configured so that fuel spray patterns (45, 46) are formed in a combustion chamber (15), in which the swirl flow (W) of intake air is being generated, by directly injecting the fuel from a fuel injection nozzle (4) having a multiple nozzle hole structure. The diesel engine (1) is provided with a superposition avoidance structure for reducing the superposition of the fuel spray patterns (45, 46) emitted from adjacent nozzle holes (34a, 35a). A valve timing mechanism (17) is provided as the superposition avoidance structure, and the valve timing mechanism (17) sets the timing (29a, 50a, 51 a), which is the start point of the valve closing operation of air intake valves (3c, 3c) for sucking air into the combustion chamber (15), to a point before the bottom dead center (B) of air intake. Also, the valve closing operation is provided with a buffering section (52) in which the seating speed of the air intake valves (3c, 3c) is reduced to buffer the impact of the seating, and the timing (51c) which is the start point of the buffer section (52) is set to a point before the bottom dead center (B) of air intake.</p> |
