| 摘要 |
PURPOSE:To simplify the construction of an ignition circuit, by controlling the pressure of a vacuum advancer to regulate knocking. CONSTITUTION:A solenoid valve drive signal sent out from a knocking control unit 3 turns on or off a solenoid valve 4 to connect its ports (a) and (b), or (b) and (c) to each other. When the ports (a), (b) of the solenoid valve 4 are connected to each other, the negative pressure of a negative pressure source 5 acts to one chamber 71A of a vacuum advancer 71. When the ports (b), (c) of the solenoid valve 4 are connected to each other, the chamber 71A of the vacuum advancer 71 are opened to the atmosphere. The vacuum advancer 71 has two chambers, one of which is the chamber 71A for regulation of knocking and the other is a chamber 71B for conventional vacuum advancement. This results in simplifying the construction of an ignition circuit. |
