| 摘要 |
PURPOSE:To simplify constitution, by providing a stepped cam and a negative pressure operated mechanism performing two-stage action to a throttle valve actuating mechanism and controlling a throttle valve opening at idling and deceleraton with a single mechanism. CONSTITUTION:A roller 5b in an arm member 5 integrally turned with a throttle valve 2 in an intake path 1 is contacted with a stepped cam 8, and the cam 8 is driven by a negative pressure operated mechanism 12. At starting of an engine, if an intake pipe negative pressure is generated, a control valve 19 is closed, and a negative pressure chamber 14 is communicated to the intake pipe 1 through an orifice of the valve 19, while a diaphragm 13 turns the cam 8 to open the valve 2 to an idle opening, if a control valve 21 is opened interlocking to an electric load operating switch, the negative pressure is introduced to a negative pressure chamber 16 and the throttle valve is further opened by a diaphragm 15. At deceleration, if the valve 2 tends to rapidly close, the roller 5b is adapted to stepped parts 10, 11 of the cam 8, and the throttle valve is fixed to the idle opening or above to suppress the negative pressure. |
