An ignition control device is provided with an ignition coil including a primary coil and a secondary coil, a main ignition circuit performing a main ignition operation, an energy input circuit that performs an energy input operation for superposing a current having the same polarity to a secondary current, in which a signal generation circuit is provided to generate, based on a main ignition signal that controls the main ignition operation, at least one of an energy input signal controlling the energy input operation and a target secondary current command signal commanding a target secondary current value.

An ignition device for an internal combustion engine includes an ignition coil, a first switch, a secondary current adjuster, and controller. The ignition coil includes a primary coil, a core, and a secondary coil. The first switch switches an energized state of the primary coil between an ON state and an OFF state. The secondary current adjuster adjusts a current value of a secondary current flowing through the secondary coil. The controller controls the secondary current adjuster so that a current value of the secondary current in at least a part of a charging period of the ignition plug, which is a period from when the energized state of the primary coil is switched from the ON state to the OFF state by the first switch to when dielectric breakdown occurs in the ignition plug, becomes smaller than a peak value of the secondary current after the dielectric breakdown occurs.

An ignition device for an internal combustion engine includes an ignition coil, a first switch, a secondary current adjuster, and controller. The ignition coil includes a primary coil, a core, and a secondary coil. The first switch switches an energized state of the primary coil between an ON state and an OFF state. The secondary current adjuster adjusts a current value of a secondary current flowing through the secondary coil. The controller controls the secondary current adjuster so that a current value of the secondary current in at least a part of a charging period of the ignition plug, which is a period from when the energized state of the primary coil is switched from the ON state to the OFF state by the first switch to when dielectric breakdown occurs in the ignition plug, becomes smaller than a peak value of the secondary current after the dielectric breakdown occurs.

Apparatuses, methods, and systems for igniting fuel for an internal combustion engine, an ignition system include a first ignition device associated with a pre-combustion chamber of a cylinder and a second ignition device associated with a main combustion chamber of the cylinder. An engine control unit is operably connected to both the engine and the ignition system to ignite fuel for the cylinder with the first ignition device independently of igniting fuel with the second ignition device. The engine control unit determines an occurrence of a combustion condition and in response thereto (i) ignites fuel for combustion with both the first and the second ignition devices or (ii) ignites fuel for combustion only with the second ignition device. The engine control unit determines a second combustion condition and in response thereto ignites fuel only with the first ignition device.

Apparatuses, methods, and systems for igniting fuel for an internal combustion engine, an ignition system include a first ignition device associated with a pre-combustion chamber of a cylinder and a second ignition device associated with a main combustion chamber of the cylinder. An engine control unit is operably connected to both the engine and the ignition system to ignite fuel for the cylinder with the first ignition device independently of igniting fuel with the second ignition device. The engine control unit determines an occurrence of a combustion condition and in response thereto (i) ignites fuel for combustion with both the first and the second ignition devices or (ii) ignites fuel for combustion only with the second ignition device. The engine control unit determines a second combustion condition and in response thereto ignites fuel only with the first ignition device.

An ignition control system for an internal combustion engine includes a controller, which includes an IGT generating section and an IGW generating section and is connected to ignition devices through an IGT signal line and an IGW signal line. The IGW signal line includes bifurcated portions, which sequentially bifurcate from a common main signal line. The bifurcated portions each correspond to one of the ignition devices and include a branched line, which is connected to an energy supply circuit inside the corresponding ignition device.

An ignition control system for an internal combustion engine includes a controller, which includes an IGT generating section and an IGW generating section and is connected to ignition devices through an IGT signal line and an IGW signal line. The IGW signal line includes bifurcated portions, which sequentially bifurcate from a common main signal line. The bifurcated portions each correspond to one of the ignition devices and include a branched line, which is connected to an energy supply circuit inside the corresponding ignition device.

An ignition device for an internal combustion engine includes an ignition coil, a first switch, a secondary current adjuster, and controller The ignition coil includes a primary coil, a core, and a secondary coil. The first switch switches an energized state of the primary coil between an ON state and an OFF state. The secondary current adjuster adjusts a current value of a secondary current flowing through the secondary coil. The controller controls the secondary current adjuster so that a current value of the secondary current in at least a part of a charging period of the ignition plug, which is a period from when the energized state of the primary coil is switched from the ON state to the OFF state by the first switch to when dielectric breakdown occurs in the ignition plug, becomes smaller than a peak value of the secondary current after the dielectric breakdown occurs.

An ignition device for an internal combustion engine includes an ignition coil, a first switch, a secondary current adjuster, and controller The ignition coil includes a primary coil, a core, and a secondary coil. The first switch switches an energized state of the primary coil between an ON state and an OFF state. The secondary current adjuster adjusts a current value of a secondary current flowing through the secondary coil. The controller controls the secondary current adjuster so that a current value of the secondary current in at least a part of a charging period of the ignition plug, which is a period from when the energized state of the primary coil is switched from the ON state to the OFF state by the first switch to when dielectric breakdown occurs in the ignition plug, becomes smaller than a peak value of the secondary current after the dielectric breakdown occurs.

A method for controlling the ignition energy of a sparkplug electrode of an ignition system comprises: providing a base current (I.sub.base) and a base duration (D.sub.base) which corresponds to the current and duration, respectively, of a physical model at a fixed engine operating point; multiplying the base current (I.sub.base) and the base duration (D.sub.base) with a sparkplug state indicator (SSI) based correction factor and with an engine operating state (EOS) based factor for achieving a final global current (I.sub.glo) and a final global duration (D.sub.glo), respectively; and communicating the final global current (I.sub.glo) and the final global duration (D.sub.glo) to a control unit for controlling the ignition energy and ignition duration of the sparkplug electrode. Further executing real-time energy control based on misfire flag status and, in the end, making sure that the optimum energy is into application by realizing optimum energy tests.