JP2000283014A - Ignition device for intenral combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform an ignition control with a characteristic suitable to each operating condition by independently or selectively driving a first ignition coil and second ignition coil having different ignition characteristics. SOLUTION: When no misfire (ST3), no knocking (ST4), target equivalent ratio of 1 or more (ST5), and EGR rate of 10% or less (ST6) are judged in OFF state of a start switch (ST2), an ignition signal for a first ignition coil with quick startup of secondary voltage and short discharge time is outputted (ST7). When homogeneous lean combustion is judged with a target equivalent ratio of less than 1 (ST8), an ignition signal for a second coil with slow startup of secondary voltage and long discharge time is outputted (ST9). In case of not homogeneous lean combustion but stratified combustion, the output of the ignition signals for the first ignition coil and second ignition coil is controlled so that the first ignition coil and second ignition coil are simultaneously driven to perform a double-ignition.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ignition device for an internal combustion engine, and more particularly, to a technology for obtaining an ignition characteristic according to an operation state of the engine.

[0002]

2. Description of the Related Art In order to make the characteristic of an ignition coil of an internal combustion engine have a fast rise of a secondary voltage, energy is released in a short time by reducing the number of secondary windings of the ignition coil. Therefore, the discharge time is shortened,
On the other hand, in order to make the characteristic that the discharge time is long, the energy is released for a long time by increasing the number of secondary windings of the ignition coil, so that the rise of the secondary voltage is delayed. ing.

[0003]

Conventionally, during operation at a stoichiometric air-fuel ratio or an air-fuel ratio richer than the stoichiometric air-fuel ratio, the secondary voltage rises so that good ignition performance against smoldering of the spark plug is obtained. It was sufficient to provide an ignition coil with a fast characteristic, but when operating with an air-fuel ratio sufficiently leaner than the stoichiometric air-fuel ratio, a characteristic that requires a long discharge time to maintain a stable combustion state is required. .

[0004] However, even in an engine that operates with a lean air-fuel ratio as described above, it is necessary to operate at a stoichiometric air-fuel ratio or an air-fuel ratio richer than the stoichiometric air-fuel ratio at the time of starting or at a high load. A long characteristic and a characteristic in which the rise of the secondary voltage is fast are required. Also, when stratified combustion is performed by forming a stratified mixture in a combustion chamber as in a recently developed engine, a good ignition performance against smoldering for a rich mixture around an ignition plug. Is required to have a fast rise of the secondary voltage so that a stable combustion state can be maintained for the outer lean mixture. In addition, in the stratified combustion, since there is a large variation in the air-fuel ratio in terms of space and time (combustion cycle), there is a demand for double ignition for the purpose of avoiding misfire.

[0005] If the ignition energy of the ignition coil is set to be large, it is possible to prolong the discharge time while increasing the rising secondary voltage. However, if the operation is performed in which the ignition energy is constantly increased, power consumption is reduced. As a result, the electrodes of the spark plug may be consumed, or the amount of heat generated by the power transistor may be increased, thereby deteriorating the durability.

The present invention has been made in view of such a conventional problem, and provides an ignition device for an internal combustion engine capable of obtaining ignition characteristics according to the operation state of the engine while suppressing power consumption. The purpose is to:

[0007]

For this reason, the first aspect of the present invention provides a first ignition coil having a characteristic that a secondary voltage rises relatively quickly and has a short discharge time, as shown in FIG. A second ignition coil having a characteristic that the rise of the secondary voltage is relatively slow and the discharge time is long, and an ignition control means for independently driving the first ignition coil and the second ignition coil according to an engine operating state And is characterized by comprising.

According to the first aspect of the invention, the ignition control means selects and drives one or both of the first ignition coil and the second ignition coil in accordance with the engine operating state.

Accordingly, the first ignition coil is driven during the operation in which the characteristic that the secondary voltage rises quickly is required,
The second ignition coil is driven during operation in which the characteristic requiring a long discharge time is required, and the first ignition coil and the second ignition coil are simultaneously operated in the operation requiring the characteristic in which the secondary voltage rises quickly and the characteristic requires a long discharge time. By driving, ignition control can be performed with characteristics suitable for each operating condition. Further, power consumption can be suppressed to a necessary minimum, and a decrease in durability can be prevented.

Further, the invention according to claim 2 is characterized in that the ignition control means drives only the first ignition coil at the time of starting or at the time of operation at a stoichiometric air-fuel ratio or an air-fuel ratio richer than the stoichiometric air-fuel ratio. I do.

According to the second aspect of the present invention, the ignition control means selects and drives only the first ignition coil at the time of starting or at the time of operation at a stoichiometric air-fuel ratio or an air-fuel ratio richer than the stoichiometric air-fuel ratio. Sometimes, it is easy to smolder due to low temperature or rich mixture,
By driving the first ignition coil having a characteristic in which the secondary voltage rises quickly, poor ignition performance due to smoldering can be prevented, and good ignition performance can be ensured.

According to a third aspect of the present invention, the ignition control means drives only the second ignition coil during a homogeneous lean combustion operation or an operation in which the EGR is performed at a stoichiometric air-fuel ratio at a predetermined EGR rate or more. It is characterized by.

According to the third aspect of the present invention, during homogeneous lean combustion operation or at a stoichiometric air-fuel ratio, the EG exceeds the predetermined EGR rate.
In the operation for performing R, the ignition control means selects and drives only the second ignition coil.

That is, in the homogeneous lean combustion, as shown in FIG. 2, the prolonged discharge time stabilizes the flammability and expands the lean limit. By performing ignition by
HC and C by expanding lean limit while stabilizing flammability
Promotes reduction of O etc. and improvement of fuel efficiency.
As shown in FIG. 3, combustion is stabilized by prolonging the discharge time and the EGR limit is extended, as shown in FIG. 3, so that the ignition is performed by the second ignition coil having the characteristic that the discharge time is long. By performing the above, the EGR limit is expanded while the combustibility is stabilized, and NOx reduction and fuel efficiency improvement are promoted.

Further, the invention according to a fourth aspect is characterized in that the ignition control means drives both the first ignition coil and the second ignition coil during the stratified combustion operation.

According to the fourth aspect of the invention, during the stratified charge combustion operation, the ignition control means selects and drives both the first ignition coil and the second ignition coil.

That is, by driving the first ignition coil having a characteristic that the rise of the secondary voltage is fast, it is possible to obtain good ignition performance against smoldering due to a rich mixture around the ignition plug in stratified combustion. Further, by driving the second ignition coil having a characteristic that the discharge time is long, a stable combustion state can be maintained for the lean mixture on the outside. In addition, by simultaneously driving the first ignition coil and the second ignition coil to perform double ignition, it is possible to avoid occurrence of misfire due to spatial and temporal (combustion cycle) variations in air-fuel ratio in stratified combustion. be able to.

According to a fifth aspect of the present invention, the ignition control means drives both the first ignition coil and the second ignition coil when a misfire is detected other than during the stratified charge combustion operation, and performs the misfire during the stratified charge combustion operation. When it is detected, only the first ignition coil is driven.

According to the fifth aspect of the invention, when a misfire is detected other than during the stratified charge combustion operation, the ignition control means
The first ignition coil and the second ignition coil are both selected and driven, and when misfire is detected during the stratified charge combustion operation, the ignition control means selects and drives only the first ignition coil.

That is, misfires in combustion other than stratified combustion include:
There are two cases of misfiring due to smoldering and misfiring due to an excessively lean air-fuel ratio. Therefore, there is a first ignition coil with a rapid rise of the secondary voltage effective for smoldering, and a misfire due to excessive leaning. On the other hand, by simultaneously driving the second ignition coil having the characteristic that the effective discharge time is long, and performing the double ignition, it is configured to surely prevent both misfires.

Further, since misfiring in stratified combustion is caused by excessive smoldering due to the rich mixture around the spark plug, a control for separately prohibiting stratified combustion and switching to homogeneous combustion was performed. Thus, the first ignition coil, which has a fast rise of the secondary voltage effective against smoldering, is driven to prevent misfire.

The invention according to claim 6 is characterized in that the ignition control means drives only the first ignition coil when a knocking occurrence state of a predetermined level or more is detected.

According to the present invention, when a knocking occurrence state of a predetermined level or more is detected, the ignition control means selects and drives only the first ignition coil.

That is, when knocking occurs, the tip end of the spark plug, which becomes hot, becomes a hot surface ignition source that is induced by the continuous occurrence of knocking and causes preignition.
By performing ignition by the second ignition coil having a short discharge time, the temperature of the tip end portion of the ignition plug is lowered, thereby avoiding preignition.

[0025]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an ignition device for an internal combustion engine according to the present invention will be described below. FIG. 4 shows a system configuration of an internal combustion engine provided with an ignition device according to one embodiment of the present invention. In the figure, an accelerator opening sensor 1 detects the amount of depression of an accelerator pedal depressed by a driver.

The crank angle sensor 2 generates a position signal for each unit crank angle and a reference signal for each cylinder stroke phase difference, and measures the number of the position signals generated per unit time, or generates the reference signal. By measuring the period, the engine rotation speed Ne can be detected.

The air flow meter 3 detects the amount of air taken into the engine 4 per unit time. The water temperature sensor 5 detects the temperature of the cooling water of the engine 4. In the cylinder part of the engine 4,
A fuel injection valve 7 for directly injecting fuel into the combustion chamber 6 and an ignition plug 8 for performing spark ignition in the combustion chamber 6 are provided. As shown in FIG. 7, the first ignition coil 9 has a characteristic that the secondary voltage rises relatively quickly and has a short discharge time.
As shown in the figure, a second ignition coil 10 having a characteristic that the rise of the secondary voltage is relatively slow and the discharge time is long is provided, and the first ignition coil 9 and the second ignition coil 10
As will be described later, it is configured to be able to be driven independently via on / off of a power transistor for each coil.

In the low / medium load range, fuel is injected into the combustion chamber 6 in the compression stroke to form a flammable mixture around the ignition plug 8 in the combustion chamber 6 to perform stratified combustion. In the high load region, fuel is injected into the combustion chamber 6 during the intake stroke to form a mixture having a substantially uniform mixture ratio over the entire cylinder, thereby enabling homogeneous combustion.

A throttle valve 12 is interposed in the intake passage 11 of the engine 4, and a throttle valve control device 13 capable of electronically controlling the opening of the throttle valve 12 and an opening of the throttle valve 12 are detected. A throttle sensor 14 is provided.

On the other hand, an exhaust passage 15 of the engine 4 has an air-fuel ratio sensor 16 for detecting an air-fuel ratio from a specific component such as oxygen in the exhaust gas, an upstream exhaust purification catalyst 17, and a downstream exhaust purification catalyst 1.
8. A muffler 19 is provided. In addition, a knock sensor 20 for detecting a knocking occurrence state is provided.

The various sensors, ignition switch IGN SW, starter switch ST SW, battery voltage Vb
And the like, are input to a control unit 21. The control unit 21 opens the throttle valve 12 via the throttle valve control device 13 in accordance with an operating state detected based on signals from the sensors. The fuel injection valve 7 is driven to control the fuel injection amount (fuel supply amount), the ignition timing is set, and the ignition plug 8 is ignited at the ignition timing.

Further, an EGR passage 22 for recirculating a part of the exhaust gas from the exhaust passage 15 of the engine to the intake passage 11 is provided.
EG comprising an EGR valve 23 interposed in the R passage 22
An R device is provided. The EGR is performed based on a control signal from the control unit 21 and is executed at the time of the stratified combustion, but is prohibited in the homogeneous lean combustion switched from the stratified combustion. During homogeneous stoichiometric combustion by feedback control at the stoichiometric air-fuel ratio, E
GR control is performed.

FIG. 5 shows a functional configuration of the above embodiment.
The target torque setting unit sets the target torque of the engine by searching a map or the like based on the accelerator opening and the engine speed.

The target EGR amount and the target fresh air amount calculation unit calculates the target EGR amount and the target fresh air amount based on the calculated target torque and engine speed. The EGR valve opening and throttle opening calculating section calculates the calculated target E
A target EGR rate is calculated based on the GR amount and the target fresh air amount, and an EGR valve opening and a throttle opening corresponding to the target EGR rate are calculated.

The target equivalence ratio calculation section calculates the target equivalence ratio based on the engine speed, target torque, water temperature and the like. More specifically, a determination is made as to switching between the combustion states [stratified combustion and homogeneous combustion (homogeneous lean combustion, homogeneous stoichiometric combustion, homogeneous rich combustion)] based on each of the above parameters, and a target equivalence ratio corresponding to each combustion state is set. .

The ignition timing calculation unit includes a target injection ratio, a target EGR rate, a knocking signal from a knock detection unit, and the like, in addition to the basic injection pulse width and the engine speed, which are load signals of the engine from the intake air amount measurement unit. Is calculated based on the ignition timing. Here, the ignition timing is calculated for the first ignition coil 9 and the second ignition coil 10 as the respective power cutoff timings.

The ignition signal output unit outputs the ignition timing signal, the knocking signal, the target EGR rate signal, the target equivalent ratio signal,
Based on the misfire determination result from the misfire determination unit, and signals of an ignition switch, a starter switch, and a battery voltage, one or both of the driving of the first ignition coil 9 and the second ignition coil 10 are selected and selected. The ignition coil is driven to cause ignition at the calculated ignition timing.

Hereinafter, specific ignition timing control by the above device will be described with reference to the flowchart shown in FIG.
In step 1, it is determined whether or not the ignition switch IGN SW is on. If the ignition switch is off, this routine ends. If it is on, the process proceeds to step 2.

In step 2, the starter switch ST SW
Is determined to be on, and if it is on, step 7
Then, the ignition timing of the first ignition coil 9 is calculated and an ignition signal is output so that only the first ignition coil 9 is selected and driven. That is, at the time of starting (at the time of cranking) in which the start switch ST SW is ON, ignition is performed by the first ignition coil 9 having a characteristic that the rise of the secondary voltage is fast in order to prevent poor starting due to smoldering.

If it is determined that the starter switch ST SW is off, the routine proceeds to step 3, where it is determined whether a misfire has occurred based on the engine speed fluctuation level and the like. If it is determined in step 3 that there is no misfire, the process proceeds to step 4 to determine whether knocking has occurred. Here, when knocking of a predetermined level or more occurs, for example, when knocking occurrence state continues for a predetermined time, it is determined that knocking is present.

If it is determined in step 4 that there is no knocking, the process proceeds to step 5, where it is determined whether the target equivalent ratio is homogeneous stoichiometric combustion or homogeneous rich combustion of 1 or more. When it is determined that the target equivalent ratio is 1 or more, the process proceeds to step 6.

In step 6, it is determined whether the EGR rate is equal to or less than a predetermined value (for example, 10%). If it is determined in step 6 that the EGR rate is equal to or less than the predetermined value, step 7
Then, the ignition timing of the first ignition coil 9 is calculated and an ignition signal is output so that only the first ignition coil 9 is driven. That is, when the target equivalence ratio is 1 or more (the mixture concentration is higher than the stoichiometric air-fuel ratio) and a large amount of EGR is not performed,
Even if the discharge time is short, stable combustion performance can be obtained,
In order to improve smoldering and ignitability at low temperatures, ignition is performed by the first ignition coil 9 having a characteristic in which the rise of the secondary voltage is fast.

On the other hand, if it is determined in step 5 that the target equivalent ratio is lean combustion, the routine proceeds to step 8, where it is determined whether homogeneous lean combustion is performed. If it is determined in step 8 that the combustion is homogeneous lean, the process proceeds to step 9 in which the ignition timing of the second ignition coil 10 is calculated and an ignition signal is output so that only the second ignition coil 10 is selected and driven. I do. In other words, the prolonged discharge time stabilizes the flammability of the lean air-fuel ratio and expands the lean limit. Therefore, by igniting with the second ignition coil 10 having a long discharge time, the flammability is improved. By increasing the lean limit while stabilizing, the reduction of HC, CO, etc. and the improvement of fuel efficiency are promoted.

Also, when the determination in step 6 is NO, that is, when the EGR is performed at a larger EGR rate than the predetermined value in the homogeneous stoichiometric combustion or the homogeneous rich combustion having the target equivalent ratio of 1 or more, the routine proceeds to step 9 and proceeds to step 9. 2 The ignition is performed by the ignition coil 10. That is, when a large amount of EGR is performed, reduction of NOx and improvement of fuel efficiency by reduction of pumping loss can be achieved at the same time, but combustion stability decreases. On the other hand, if the ignition discharge time is lengthened, the combustibility is stabilized, and the EGR limit is expanded. Therefore, by performing ignition with the second ignition coil 10 having a long discharge time when a large amount of EGR is performed, the EGR limit is expanded while the combustibility is stabilized, and NOx reduction and fuel efficiency improvement are promoted.

If it is determined in step 8 that the combustion is not homogeneous lean combustion, it means that stratified combustion is being performed. In this case, the routine proceeds to step 10, where the first ignition coil 9
The ignition timings of the first ignition coil 9 and the second ignition coil 10 are calculated so as to simultaneously drive the second ignition coil 10 and the second ignition coil 10 and output an ignition signal to each.

That is, in the stratified combustion, a characteristic that the secondary voltage rises quickly is required for a rich mixture around the spark plug so as to obtain good ignition performance against smoldering. A characteristic that a discharge time is long is required for a lean air-fuel mixture so that a stable combustion state can be maintained. Therefore, as shown in FIG. 9, the first ignition coil 9 and the second ignition coil 1
0 is simultaneously driven to perform ignition. In addition, in the stratified combustion, the spatial and temporal (combustion cycle) variation in the air-fuel ratio is large, but when the first ignition coil 9 and the second ignition coil 10 are driven simultaneously, the secondary voltage of the first ignition coil 9 is increased. , The secondary voltage of the second ignition coil 10 is slowly increased to perform double ignition, and the spatial and temporal variations in the air-fuel ratio are caused by the double ignition. This can avoid the occurrence of misfire due to the fire.

On the other hand, if it is determined in step 3 that there is a misfire, the routine proceeds to step 11, where it is determined whether or not stratified combustion is being performed. If it is determined that stratified charge combustion is not being performed, the routine proceeds to step 10, where the first ignition coil 9 and the second ignition coil 10 are simultaneously driven to perform double ignition. In other words, misfires in homogeneous combustion other than stratified combustion are assumed to be two cases, misfires due to smoldering and misfires due to an excessively lean air-fuel ratio. By simultaneously driving the first ignition coil 9 having a fast rise of the secondary voltage and the second ignition coil 10 having a long discharge time effective against misfiring due to excessive lean, and performing double ignition, To prevent misfires. Alternatively, if the target equivalent ratio is larger than the predetermined value A and it is clear that the cause of misfire is smoldering based on the target equivalent ratio at the time of homogeneous combustion, only the first ignition coil 9 is driven and the target equivalent ratio is reduced. If it is clear that the cause of misfire is smaller than the predetermined value B and it is clear that the cause is excessive lean, only the second ignition coil 10 is driven,
When the target equivalent ratio is equal to or greater than the predetermined value B and equal to or less than the predetermined value A,
It is determined that there is a possibility that the misfire is caused by smoldering or excessive lean, and the first ignition coil 9 and the second ignition coil 10 are simultaneously driven to perform double ignition. Power consumption can be further reduced.

If it is determined in step 11 that misfiring is occurring during stratified combustion, misfiring during stratified combustion is due to excessive smoldering due to the rich mixture around the spark plug. Proceeding to step 12, the stratified combustion is prohibited, the target air-fuel ratio is switched to homogeneous combustion of 1 or more, and then proceed to step 7, where only the first ignition coil 9, which is effective for smoldering and has a fast rising secondary voltage, is used. Drive to prevent misfire. After once prohibiting stratified combustion in this way, at the time when it is predicted that the electrode of the ignition plug 8 has been self-cleaned from the engine speed, the engine load such as the target torque, the elapsed time, etc., the stratified combustion is started. It is good to adopt a configuration to return.

Next, if it is determined in step 4 that knocking has occurred (knocking duration is long), the flow advances to step 13 to determine whether or not the target equivalent ratio is 1 or more. When the target equivalence ratio is less than 1, the routine proceeds to step 14 to prohibit the lean combustion and correct the target equivalence ratio to 1 or more to obtain the homogeneous stoichiometric or homogeneous rich combustion. Step 7 proceeds, and ignition is performed only by the first ignition coil 9. That is,
When knocking occurs during lean combustion, first, switching to homogeneous stoichiometric or homogeneous rich combustion is performed to suppress knocking. Further, when knocking occurs, pre-ignition that causes engine damage is induced due to the continuous occurrence of knocking. At this time, the hot surface ignition source causing preignition is the tip of the spark plug, which becomes high in temperature. As means for lowering the temperature of the tip, ignition by the second ignition coil 10 having a short discharge time is effective. Become. When knocking occurs, retard control of the ignition timing that is performed separately is also used.

FIG. 10 shows a configuration example of the ignition circuit.
(A) shows a case in which an ignition signal is supplied from a common ignition coil to all cylinders via a distributor to all cylinders, and the first ignition coil 9 and the second ignition coil 10 are respectively connected to the primary side. The power transistors Tr1 and Tr2 are connected, and the secondary side is connected to the spark plug 8 via diodes D1 and D2.
Connected to the electrodes. The power transistor Tr1,
By selecting and driving Tr2, the first ignition coil 9 and the second ignition coil 10 can be selected and driven.

(B) shows the case of an electronic power distribution system in which an ignition coil is provided for each cylinder. A power transistor T is provided on the primary side of the first ignition coil 9 and the second ignition coil 10 for each cylinder.
r1 and Tr2 are connected, and the secondary sides are diodes D1 and D2.
2 is connected to the electrode of the ignition plug 8 via the second, and by selectively driving the power transistors Tr1 and Tr2, the first ignition coil 9 and the second ignition coil 10 can be selectively driven. The same is true. In this system, ignition control (including combustion switching) common to all cylinders may be performed, but, for example, misfire determination and knocking determination are performed for each cylinder, and ignition control (including combustion switching) is performed for each cylinder. It may be.

FIG. 11 shows an embodiment of an ignition coil with a built-in power transistor applied to the electronic distribution system shown in FIG. 10B, in which a primary ignition coil 24 and a secondary ignition coil 25 are concentric. Prepare above.

[Brief description of the drawings]

FIG. 1 is a block diagram showing the configuration and functions of the present invention.

FIG. 2 is a view showing a relationship between a discharge time of an ignition plug and a lean equivalent ratio.

FIG. 3 is a diagram showing a relationship between a discharge time of an ignition plug and an EGR limit.

FIG. 4 is a diagram showing a system configuration of an ignition device for an internal combustion engine according to one embodiment of the present invention.

FIG. 5 is a block diagram showing a functional configuration of the embodiment.

FIG. 6 is a flowchart showing an ignition control routine according to the embodiment.

FIG. 7 is a view showing characteristics of a first ignition coil of the embodiment.

FIG. 8 is a view showing characteristics of a second ignition coil of the embodiment.

FIG. 9 is a view showing characteristics when the first ignition coil and the second ignition coil of the embodiment are simultaneously driven.

FIG. 10 is a diagram showing ignition circuits in two modes of the embodiment.

FIG. 11 is a sectional view of an example of the ignition coil according to the embodiment;

[Explanation of symbols]

 Reference Signs List 4 internal combustion engine 7 fuel injection valve 8 spark plug 9 first ignition coil 10 second ignition coil 21 control unit 22 EGR passage 23 EGR valve

Claims (6)

[Claims] A first ignition coil having a characteristic that a rise of a secondary voltage is relatively fast and a discharge time is short;
A second ignition coil having a characteristic that the rise of the next voltage is slow and the discharge time is long; and ignition control means for independently driving the first ignition coil and the second ignition coil according to an engine operating state. An ignition device for an internal combustion engine, comprising: 2. The internal combustion engine according to claim 1, wherein said ignition control means drives only the first ignition coil at the time of starting or at the time of operation at a stoichiometric air-fuel ratio or an air-fuel ratio richer than the stoichiometric air-fuel ratio. Engine ignition device. 3. The ignition control device according to claim 1, wherein the ignition control means drives only the second ignition coil during a homogeneous lean combustion operation or an operation in which the EGR is performed at a stoichiometric air-fuel ratio at a predetermined EGR rate or more. The ignition device for an internal combustion engine according to claim 2. 4. The internal combustion engine according to claim 1, wherein the ignition control means drives both the first ignition coil and the second ignition coil during the stratified charge combustion operation. Engine ignition device. 5. The ignition control means drives both the first ignition coil and the second ignition coil when a misfire is detected other than during the stratified charge combustion operation, and when the misfire is detected during the stratified charge combustion operation, only the first ignition coil is provided. The ignition device for an internal combustion engine according to any one of claims 1 to 4, wherein the ignition device is driven. 6. The system according to claim 1, wherein said ignition control means drives only said first ignition coil when detecting a knocking occurrence state of a predetermined level or more.
An ignition device for an internal combustion engine according to any one of the above.