| 摘要 |
PURPOSE:To prevent erroneous function of knocking control under light load while to perform idle lead angle in idling by controlling the negative pressure of vacuum advancer in distributor in accordance with knocking. CONSTITUTION:Under light load, negative pressure of advance port 121 will increase to open the vacuum advancer 71A to the atmosphere while 71B will lead the angle to ignition timing. Even if erroneous VSV drive signal is provided from a knocking controller under this state, the port of solenoid valve 4 will never exchange because the power source of said valve 4 is turned off by a negative pressure switch 8. While idling, the throttle valve 13 is fully closed to open the port 121 to the atmosphere thus to open the advancer 71B to the atmosphere and to stop lead angle. Consequently, said switch 8 is turned on to exchange VSV4 thus to apply negative pressure from negative pressure source 5 onto the advancer 71A and to perform idle lead angle. In such a manner, erroneous function of knocking control is prevented under light load while to perform idle lead angle in idling. |
