| 摘要 |
PURPOSE:To prevent a coil from heating up as energizing time becomes much longer, by igniting an engine on the basis of a top dead point signal alone in time of supply voltage being dropped, while limiting a time range of the top dead point signal to the fixed time range. CONSTITUTION:Usually ignition timing is controlled on the basis of both signals out of a turning angle detector 23 indicating a top dead point and another turning angle detector 24 indicating a crank angle position. When the supply voltage detected by a supply voltage detector 21 is below the specified value, an AND output between a signal of the turning angle detector 23 indicating the top dead point and a signal of a timer circuit 40 is found by an AND circuit 41 whereby the ignition timing is controlled. With this constitution, there produces no misoperation in time of a drop in the supply voltage. |
