JPS6487872A - Ignition controller for internal combustion engine - Google Patents

Abstract

PURPOSE:To save current consumption in the controller in the caption by providing an engine condition judging means and a starting ignition coil energization control means which variably controls the energization time of an ignition coil on a primary side, when the judging means judges that an engine is in a rotation starting region, so as to be firstly enough long,and then to gradually become shorter. CONSTITUTION:When an engine condition judging means in a CPU 5 judges that an engine is in a starting rotation region, an ignition coil 10 is variably controlled in such a way that, the energization time thereof on a primary side is set firstly enough long, and then that it is gradually shortened. Accordingly, in the engine starting region, the energization time of the ignition coil on the primary side can be generally taken longer than that at the time of the normal operation of the engine so as not to be excessively short. Therefore, the energization time isn't insufficient even if any rotational fluctuation occurs in a rotational region at a low speed at the time of the engine starting, and further, the energization time of the ignition coil on the primary side at the time of starting gradually becomes shorter even if it is set long and as well, time until the completion of cranking operation isn't usually long so as not to cause abnormal heat generation in a power transistor 9.