| 摘要 |
PURPOSE:To obtain the engine characteristic superior in the whole revolution range by varying the effective area of an annular passage formed between the inner peripheral surface of a suction passage and a small venturi by a subthrottle valve driven by an actuator. CONSTITUTION:A small venturi 34 is formed at the center position of a large venturi at the upstream position of a throttle valve 32 in a suction passage 31, and an annular subthrottle valve 40 which turns around a shaft 39 is installed into an annular passage 35 between the venturi 34 and the inner peripheral surface of the suction passage 31. Said valve 40 is opening/closing-perated through rod 37 and an arm 38 fixed onto the shaft 39 by a diaphragm apparatus 36 operated by a negative pressure. Onthe valve 40, a cut part 41 is formed to avoid the interference with the small venturi 34 in the case when the valve 40 turns and to form an opened port necessary for securing the inhaled-air amount in low-speed operation. |
