| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide an ignition device that extends the lifetime of an ignition plug by suppressing a voltage to be applied to the ignition plug, while preventing misfire by reliable spark discharge. <P>SOLUTION: A high-load condition, in which a load of an internal combustion engine is higher than a predetermined set value, is defined for an engine control device 70, in advance. When the internal combustion engine operates beyond the high-load condition, after start-up or during low-temperature operation, for instance, an ignition coil 30 applies a negative discharge voltage, where the negative pole is a central electrode 21 and the positive pole is a ground electrode 23, to the ignition plug 20 according to an ignition control signal by the engine control device 70. Meanwhile, when the internal combustion engine operates under the high-load condition, the ignition coil 30 applies a positive discharge voltage, where the positive pole is a central electrode 21 and the negative pole is a ground electrode 23, to the ignition plug 20 according to the ignition control signal. <P>COPYRIGHT: (C)2013,JPO&INPIT</p> |
