| 摘要 |
PURPOSE:To enable change of intake inertia depending upon the rotation speed of an engine, according to the method wherein a surge tank is communicated with a combustion chamber through a passage, the passage is communicated with a surge tank through a different passage, and control valves opening and closing their respective passages, are provided. CONSTITUTION:During low speed operation of an engine, a computer 35 turns OFF negative pressure switching valves 25 and 33, and there by negative pressure chambers 24 and 32 of actuators 22 and 30 are both released to the open air. As a result, an atmospheric pressure is exerted on the negative pressure chambers 24 and 32, and since control valves 19 and 27 are closed by springs 22d and 30d, respectively, air is sucked to a combustion chamber 5 only through an intake passage 6b of a first passage 17. When a throttle valve 16 is opened and the rotation speed of engine is increased to a middle value, the computer 35 turns ON the negative pressure switching valve 25. As a result, a negative pressure in a negative pressure tank 26 is introduced to the negative chamber 24 of the first actuator 22 to open the first control valve 19, and thereby air is sucked to a combustion chamber 5 through intake passages 6a and 6b of the first passage 17. |
