| 摘要 |
PURPOSE:To aim at improvements in engine output in a wide range, by promoting an output improvement by means of a suction inertia effect at a specified operation range upon changing length of a suction passage, while compensating for the output improvement other than the specified operation range with a change in a suction passage area. CONSTITUTION:In a suction passage 3 interconnected to a combustion chamber 2 of each cylinder in an engine 1, there are provided with a passage length variable device 9 fitted with a cylinder member 11 slidably installed in a connecting part with a surge tank 5 and a passage area changing device 10 fitted with a moving member 12 installed in a space ranging from a nearby spot of a suction port 7 to the inside of the cylinder member 11. And, each of actuators 13 and 13 of these aforesaid devices 9 and 10 is driven and controlled by a controlling device 15, and an engine speed signal out of an engine speed sensor 16 and a load signal out of a load sensor 17 are inputted into the controlling device 15. With this constitution, at a specified operation range, length of the passage is changed, and at a spot other than the specified operation range, a passage area is change, thus the desired end comes to fruition. |
