Provided is an ignition control device capable of suppressing wear of an ignition plug due to occurrence of a re-strike without adding a component. An ECU 123 used as an ignition control device includes: an ignition signal calculation unit 203 that calculates a start timing and an end timing of re-energization with a primary current in one ignition process, compares the end timing of the re-energization with the timing at which the frequency of occurrence of a re-strike decreases, and determines whether to perform the re-energization; and an ignition signal generation unit 204 that generates an ignition signal for generating at least one or more spark discharges in the ignition process, outputs the ignition signal to the ignition coil, then generates the ignition signal when the ignition signal calculation unit determines to perform the re-energization, outputs the ignition signal to the ignition coil at the start timing of the re-energization, and does not generate the ignition signal when the ignition signal calculation unit determines not to perform the re-energization.

In an engine ignition method according to the present invention, an ignition coil and an exciter coil are provided in a magneto generator driven by an engine. After charging an ignition capacitor using an output voltage of the exciter coil, the ignition capacitor is discharged through a primary coil of the ignition coil at an ignition timing of the engine, whereby a high voltage induced in a secondary coil of the ignition coil is applied to an ignition plug and a first spark discharge is generated in the ignition plug, and a voltage induced in the secondary coil of the ignition coil accompanied with rotation of the magneto rotor is applied to the ignition plug in a state that insulation across discharge gaps of the ignition plug is broken down due to the first spark discharge, whereby a second spark discharge is produced in the ignition plug.

An internal-combustion-engine control apparatus according to the present disclosure controls an internal combustion engine having a main combustion chamber, a subsidiary combustion chamber, an ignition plug that is disposed in the subsidiary combustion chamber, an ignition coil connected with the ignition plug, and an orifice for connecting the subsidiary combustion chamber with the main combustion chamber and for injecting combustion gas in the subsidiary combustion chamber into the main combustion chamber; the internal-combustion-engine ignition apparatus includes an ignition control unit that controls energization of the ignition coil so that an ignition discharge for igniting a fuel-air mixture in the subsidiary combustion chamber is produced across the ignition plug, and a pressure-boosting control unit that controls energization of the ignition coil so that a pressure-boosting discharge for increasing a pressure of combustion gas in the subsidiary combustion chamber is produced across the ignition plug.

An ignition coil for an internal combustion engine includes a primary bobbin including a winding cylinder part and a connection part between the winding cylinder part and a connector part, a primary coil including a primary main coil and a primary sub coil, and a secondary coil. When one of the primary main coil and the primary sub coil that includes an innermost coil part around the winding cylinder part is defined as a firstly-wound coil and the other is defined as a secondly-wound coil, firstly-wound ends, which are ends of the firstly-wound coil, and secondly-wound ends, which are ends of the secondly-wound coil, are attached to the connection part, and a shortest distance from a central axis of the winding cylinder part to each of the firstly-wound ends is smaller than a shortest distance from the central axis of the winding cylinder part to each of the secondly-wound ends.

In an engine including an auxiliary chamber having an ignition plug therein, an amount of heat generated in the auxiliary chamber tends to be large, and thus it is necessary to suppress abnormal combustion. However, when a sensor is added to the ignition plug, a manufacturing cost of the ignition plug tends to increase. An ECU 2 includes an auxiliary chamber temperature estimation unit 21 that estimates a temperature of the auxiliary chamber 42, and an ignition control unit 22 that delays an ignition timing at a first decrease degree defined in accordance with a change amount of the ignition timing with respect to the temperature of the auxiliary combustion chamber as the temperature of the auxiliary chamber 42 increases in a case where the estimated temperature of the auxiliary chamber 42 is included in a middle temperature region equal to or lower than a first set temperature.

In an engine including an auxiliary chamber having an ignition plug therein, an amount of heat generated in the auxiliary chamber tends to be large, and thus it is necessary to suppress abnormal combustion. However, when a sensor is added to the ignition plug, a manufacturing cost of the ignition plug tends to increase. An ECU 2 includes an auxiliary chamber temperature estimation unit 21 that estimates a temperature of the auxiliary chamber 42, and an ignition control unit 22 that delays an ignition timing at a first decrease degree defined in accordance with a change amount of the ignition timing with respect to the temperature of the auxiliary combustion chamber as the temperature of the auxiliary chamber 42 increases in a case where the estimated temperature of the auxiliary chamber 42 is included in a middle temperature region equal to or lower than a first set temperature.

An ignition system and a method for operating an ignition system for an internal combustion engine are provided, including a primary voltage generator and a boost converter for generating an ignition spark. An ascertainment of a voltage requirement for the ignition spark is followed by a modification of a switch-on time of the boost converter relative to a switch-off time of the primary voltage generator.

Disclosed is a method for determining a need for changing a spark plug of a combustion engine, comprising the following steps: monitoring a current flowing through the spark plug, analyzing the current and thereby determine a time interval that is indicative for the time between application of a voltage to the spark plug and formation of an arc discharge between electrodes of the spark plug, creating a signal indicative of the need to change the spark plug if the duration of the determined time interval is outside predefined bounds.

In order to transmit high frequency energy to a coupling circuit, if the high frequency energy is transmitted via a harness provided with a high-voltage cable, the loop in which the high frequency energy is conducted is long, and thus, noise occurring from the loop is increased. Thus, shielding is needed to be provided to the entire apparatus. The present invention has a structure in which: a high frequency energy supply circuit and a coupling circuit are connected by a connection member; and a housing having therein the high frequency energy supply circuit is integrated with a housing having therein the coupling circuit. Accordingly, the entire apparatus can be downsized and noise occurring from the loop can be reduced.

The ignition control device includes a spark plug that includes a first electrode and a second electrode disposed so as to oppose each other, an ignition coil that includes a plurality of sets of a primary coil and a secondary coil, generates a high voltage in the secondary coil by energizing or interrupting a primary current supplied to the primary coil, and applies the generated high voltage to the first electrode, and a control unit that, in a case where a plurality of the primary coils are driven during a single ignition process, temporarily stops energization of a primary current supplied to a second primary coil when a primary current supplied to a first primary coil is interrupted, and re-energizes the primary current supplied to the second primary coil following the elapse of an energization stoppage period.