| 摘要 |
PURPOSE:To prevent the occurrence of erroneous operations by modifying a cylinder discrimination signal with an ignition signal synchronous to the rotation of an engine and a cylinder discrimination signal having a period two times as large as that of the ignition signal and by controlling the excitation of an ignition coil by use of the logic with the ignition signal. CONSTITUTION:An ingnition signal sensor 1 generates an ignition signal A synchronous to the rotation of an engine, and a sensor 2 generates a cylinder dicrimination signal B having a period twice as large as that of the ignition signal. Using a data flip-flop 15, these two signals A, B are modified into a cylinder discrimination signal which alternates at the changing point of the ignition signal reference edge, and the excitation of an ignition coil 11 is controlled by using the logic with the ignition signal A. When the phase of the ignition signal is largely changed by an ignition timing control circuit 4, the phase of the cylinder discrimination signal changes accordingly to it, and the ignition signal is reliably distributed. In this way, a broad range of spark advance angle becomes available without causing any erroneous operation. |
