| 摘要 |
PURPOSE:To prevent misignition even if the cylinder discrimination sensor on one side fails by constituting a discrimination circuit so that whether or not both cylinder discrimination sensors are normal is discriminated by basing on whether the respective cylinder discrimination signals of both cylinder discrimination sensors, which generate respective cylinder discrimination signals whose phases are same or opposite each other, are of the same or opposite phase. CONSTITUTION:The first and second power transistors 31 and 32 are selected by the output of the first rotor 11 as well as the first and second cylinder discrimination sensors 11A and 11B, and the closing angle and opening timing of both power transistors 31 and 32 are generated by the output of an ignition signal sensor comprising of the second rotor 12 and en electromagnetic pickup 12b to obtain proper ignition. Further, even if one of the cylinder discrimination sensors 11A and 11B fails and the output of these sensors is fixed to a high or low level, since an exclusive OR circuit 51 of the output of both cylinder discrimination sensors is constituted, the ignition signal can be distributed only to a normal cylinder and accordingly the misignition of an ignition plug can be prevented. |
