| 摘要 |
PROBLEM TO BE SOLVED: To improve a volumetric efficiency at a high rotation side rather than the maximum torque revolution at an engine intake device while its weight and manufacturing cost are being restricted.SOLUTION: Each of the independent intake passages 23 is composed of one downstream side passage 25c and in turn at the upstream side, it is branched into first and second upstream side passages 25a, 25b. There are provided the first upstream side passage 25a and the downstream side passage 25c. A first passage 23a shows a dynamic super-charging effect under the first engine speed V1 exceeding the maximum torque revolving speed Vt. There are provided the second upstream side passage 25b and the downstream side passage 25c. Each of second passages 23b capable of attaining the dynamic super-charging effect under a state exceeding the maximum torque engine speed Vt and the second engine speed V2 lowering the first engine speed V1 is always opened. The first and the second passages 23a, 23b are connected side by side in an axial direction of the cylinder from the side surface of counter-engine side at a surge tank 21, and a difference Vd between the first engine speed V1 and the second engine speed V2 is set in 15% of the maximum engine speed Ve.SELECTED DRAWING: Figure 3 |
