| 摘要 |
PURPOSE:To improve a swirl and the extent of volumetric efficiency, by limiting one suction port of an engine provided with two suction valves at each cylinder to only helical suction, while setting the other port down to a helical port performing partial direct suction, and making an axis connecting both suction holes parallel with a cam axis. CONSTITUTION:One port 2 in two suction ports 2 and 3 of an engine provided with two suction valves at each cylinder is set down to a pure helical port having only a suction gas swirl component out of a suction hole 11, and the other port 3 is set down to a partial helical port in which suction air out of a suction hole 12 has a partial swirl component and another part has a direct component. An axis connecting both these suction holes 11 and 12 is set up so as to parallel an axis S of a can shaft. At the time of low speed, suction takes place from only the port 11, forming a strong swirl but at the time of high speed, a strong swirl and suction excellent in volumetric efficiency are carried out through both these ports. |
