| 摘要 |
<P>PROBLEM TO BE SOLVED: To efficiently achieve promotion of scavenging by ejector effect. <P>SOLUTION: The multi-cylinder engine includes: an engine body 1 having five cylinders 2A-2E having different periods of exhaust strokes by 144° of a CA (crank angle) respectively; and an exhaust device 13 connected to the engine body 1. The exhaust device 13 includes: a plurality of independent exhaust passages 14, 15, 16, a collection part 17 formed by bundling the downstream end parts of the respective independent exhaust passages 14, 15, 16 to be close to one another; and a joining part 18 connected to the downstream side of the collection part 17. The downstream end part of each independent exhaust passage 14, 15, 16 bundled in the connection part 17 is formed so that a passage cross sectional area is made smaller toward the downstream side and operation timings of intake valves 5 and exhaust valves 6 of the respective cylinders 2A-2D are set to generate a predetermined time difference between a time point when the exhaust valve 6 of one side cylinder out of cylinders which are consecutive in the exhaust order starts its opening and a time point when the another side cylinder out of the cylinders which are consecutive in the exhaust order reaches a start point of an overlap (O/L) period. <P>COPYRIGHT: (C)2013,JPO&INPIT |
