JP2006046276A - Ignition control device for direct spark ignition type internal combustion engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To optimize ignition energy based on a method for forming stratified charge mix in a case of directly injecting fuel into a combustion chamber 4 by a fuel injection valve 11 to form the stratified charge mix around a spark plug 12, and ignite the stratified charge mix for performing stratified charge combustion. <P>SOLUTION: Stratified charge combustion of a shorter interval from fuel injection timing to ignition timing than a prescribed value (that is, for example, stratified charge combustion to form stratified charge mix in an inner cavity 14 and space above it by delaying fuel injection timing in low load operation conditions) is compared with stratified charge combustion of a longer interval from fuel injection timing to ignition timing than the prescribed value (that is, for example, stratified charge combustion to form stratified charge mix in an outer cavity 15 and space above it by quickening fuel injection timing in high load operation conditions) for increasing energization time to the ignition coil so as to increase ignition energy. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an ignition control device for a direct-injection spark ignition internal combustion engine, and more particularly to a technique for optimizing ignition energy.

As a conventional technique, Patent Document 1 discloses a direct injection spark ignition type internal combustion engine capable of switching between stratified combustion by compression stroke injection and homogeneous combustion by intake stroke injection. It is described that the ignition time (discharge energy) is increased by extending the energization time to the ignition coil as compared with the case of homogeneous combustion because it is the most severe condition of misfire resistance. . On the other hand, it is also described that power consumption is reduced by reducing the ignition energy as the load increases.
JP 2001-153015 A

However, there are various methods for forming a stratified mixture in the stratified charge combustion method, and how to control the ignition energy when differently forming the stratified mixture depending on the engine speed and load, Patent Document 1 does not describe whether to stabilize ignition control and reduce power consumption.
In view of such a situation, the present invention aims to further stabilize ignition control and reduce power consumption by providing optimum ignition energy for each of various stratified combustion systems. To do.

  Therefore, according to the first aspect of the present invention, the stratified charge combustion has a stratified charge combustion period from the fuel injection timing to the ignition timing shorter than a predetermined value and a stratified charge combustion period from the fuel injection timing to the ignition timing longer than the predetermined value. In the stratified combustion where the interval from the fuel injection timing to the ignition timing is shorter than a predetermined value, the ignition energy is increased as compared with the stratified combustion where the interval from the fuel injection timing to the ignition timing is longer than the predetermined value.

  Further, in the invention of claim 3, stratified combustion which has a double cavity inside and outside the piston crown surface and injects fuel into the inner cavity to form a stratified mixture in the inner cavity and in the upper volume thereof, and the outer In the case of stratified combustion in which fuel is injected into the cavity to form a stratified mixture in the outer cavity and in its upper volume, the outer side in the stratified combustion in which the stratified mixture is formed in the inner cavity and its upper volume Compared to stratified combustion which forms a stratified mixture in and above the cavity, the energy of ignition is increased.

  Further, in the invention of claim 5, stratified combustion that directly forms a stratified mixture around the spark plug without passing through the cavity by fuel spray, and stratification that forms a stratified mixture around the spark plug through the cavity by fuel spray. In the case of stratified combustion that forms a stratified mixture around the spark plug directly by the fuel spray without passing through the cavity, the stratified combustion that forms the stratified mixture around the spark plug through the cavity by the fuel spray Compared to increase the energy of ignition.

  According to the invention of claim 11, in stratified combustion, the ignition energy when the engine operating condition is in the first operating region is increased in accordance with the increase of the load, while the engine operating condition is in the second operating region. The ignition energy is decreased as the load increases.

  According to the invention of claim 1, in the stratified combustion where the interval from the fuel injection timing to the ignition timing is shorter than a predetermined value, the air-fuel mixture around the spark plug tends to become rich. Plug smoldering and misfire can be prevented. Further, in the stratified combustion where the interval from the fuel injection timing to the ignition timing is longer than the predetermined value, the fuel spray has sufficient time to evaporate, and the air-fuel mixture field does not become too rich around the spark plug. By not increasing the ignition energy more than necessary, it is possible to prevent deterioration of fuel consumption due to an electric load, and to improve the durability of the spark plug.

  According to the third aspect of the present invention, in stratified combustion having a double cavity inside and outside and injecting fuel into the inner cavity to form a stratified mixture in the inner cavity and its upper volume, Since the air-fuel mixture tends to become rich, it is possible to prevent smoldering and misfiring of the spark plug by increasing the ignition energy. Also, in stratified combustion in which fuel is injected into the outer cavity to form a stratified mixture in the outer cavity and in the volume above it, the fuel spray has sufficient time to evaporate, and the mixture field is rich around the spark plug. Therefore, by not increasing the ignition energy more than necessary, it is possible to prevent fuel consumption deterioration due to the electric load and improve the durability of the spark plug.

  According to the invention of claim 5, in the stratified combustion in which the stratified mixture is directly formed around the spark plug by the fuel spray without passing through the cavity, the mixture around the spark plug tends to become rich, so the ignition energy is increased. By doing so, smoldering and misfire of the spark plug can be prevented. Also, in stratified combustion in which stratified mixture is formed around the spark plug through the cavity by fuel spray, the fuel spray is sufficiently evaporated due to the piston crown surface temperature, and the mixture field becomes too rich around the spark plug. Therefore, by not increasing the ignition energy more than necessary, it is possible to prevent the deterioration of fuel consumption due to the electric load and improve the durability of the spark plug.

  According to the invention of claim 11, in the stratified combustion, the ignition energy when the engine operating condition is in the first operating region is increased according to the increase in the load, while the engine operating condition is in the second operating region. By reducing the ignition energy according to the increase in the load, it becomes possible to perform optimum control according to the increase / decrease in the load for each engine operating condition.

Embodiments of the present invention will be described below with reference to the drawings.
First, a first embodiment of the present invention (corresponding to claims 1 to 4 and 7 to 13) will be described.
FIG. 1 is a configuration diagram (cross-sectional view of a main part of an engine) of a first embodiment of the present invention, (A) is a front cross-sectional view, and (B) is a side cross-sectional view.
In this internal combustion engine, a combustion chamber 4 is formed by the cylinder head 1, the cylinder block 2, and the piston 3. In the cylinder head 1, an intake port 5 and an exhaust port 6 are opened, and an intake valve 7 and an exhaust valve 8 are provided respectively. The intake valve 7 and the exhaust valve 8 are driven to open and close by an intake valve cam 9 and an exhaust valve cam 10, respectively.

  The fuel injection valve 11 is attached to the cylinder head 1 and disposed at the upper center of the combustion chamber 4. In particular, in the present embodiment, the fuel injection valve 11 is offset to the front side of the engine (to the left of FIG. 1B) and is tilted due to layout restrictions as a multi-cylinder engine. As the fuel injection valve 11, a multi-hole injection valve having a small directivity and a strong directivity is used even when the in-cylinder pressure rises in the latter half of the compression stroke.

Like the fuel injection valve 11, the spark plug 12 is attached to the cylinder head 1 and disposed at the upper center of the combustion chamber 4, but the engine rear side opposite to the fuel injection valve 11 (FIG. 1 (B ) Is offset to the right) and is inclined so as to protrude from the fuel injection valve 11 into the combustion chamber 4. Reference numeral 13 denotes an ignition coil.
An inner cavity 14 and an outer cavity 15 are formed on the crown surface of the piston 3 in an inner and outer double. That is, the piston 3 has two cavities 14 and 15 that are circular when viewed from above, and the two cavities 14 and 15 have a double structure in which the smaller one (14) is included in the larger one (15). Yes.

The operation of the fuel injection valve 11 and the spark plug 12 (ignition coil 13) is controlled by the control unit 16.
Here, the combustion methods are roughly classified into stratified combustion on a relatively low load side and homogeneous combustion on a relatively high load side. In the case of stratified combustion, a stratified mixture is formed around the spark plug 12 by compression stroke injection, and this is ignited and burned. In the case of homogeneous combustion, a homogeneous mixture is formed in the entire combustion chamber 4 by intake stroke injection, and this is ignited and burned.

In addition, among the operating conditions for performing stratified combustion, the stratified mixture forming method is made different between the low-load operating condition and the high-load operating condition.
FIG. 2 shows the spray and gas mixture behavior under the stratified low load operation condition.
Among the stratified operating conditions, under relatively low load operating conditions, fuel is injected into the inner cavity 14 by delaying the fuel injection timing in relation to the position of the piston 3. The spray that has collided with the bottom surface of the inner cavity 14 proceeds upward from the bottom surface along the side wall. As a result, a relatively small stratified mixture is formed above the inner cavity 14. Since the injection timing is set so that the spray is received in the inner cavity 14 as described above, the injection timing is set to a timing close to the piston top dead center as compared with a stratified high load operation condition described later. This shortens the interval between the injection timing and the ignition timing, and the air-fuel mixture around the spark plug 12 tends to become rich.

FIG. 3 shows the spray and gas mixture behavior under the stratified high load operation condition.
Of the stratified operating conditions, under relatively high load operating conditions, fuel is injected into the outer cavity 15 by advancing the fuel injection timing in relation to the position of the piston 3. At this time, the spray first collides with the bottom surface of the outer cavity 15. The bottom surface of the outer cavity 15 is inclined slightly downward from the cylinder center toward the outside. The spray is then guided by the side walls of the outer cavity 15 and proceeds. Since the spray penetration force is strong, the entire air-fuel mixture has a circulating flow that swirls like a vortex in the space between the lower surface of the cylinder head 1. The circulating air entrains ambient air and the air-fuel mixture generated above the outer cavity 15 becomes a homogeneous air-fuel mixture field with little concentration unevenness. Since the interval between the injection timing and the ignition timing can be made relatively long, the air-fuel mixture around the spark plug 12 does not become richer than necessary.

FIG. 4 shows an ignition coil 13 used in the present invention. Like a normal ignition coil, it has a primary side coil and a secondary side coil, energizes the primary side coil and cuts it off at the ignition timing. Occurs.
FIG. 5 shows the relationship between the primary side coil current and the secondary side coil current / voltage. The ignition energy is controlled by the length of time during which current is supplied to the primary coil. That is, when the energization time of the primary side coil current is lengthened as shown in FIG. 5B with respect to the normal ignition of FIG. 5A, the primary side coil current becomes large, and thereby the secondary side coil current increases. The current / voltage increases. Since the ignition energy is an integral value of the product of the current and voltage of the secondary coil, the ignition energy is increased by the above method.

FIG. 6 shows the relationship between the load (combustion method) and ignition energy according to the present invention.
Under stratified low load operation conditions, fuel is injected into the inner cavity and stratified combustion is performed to form a stratified mixture in the inner cavity and the volume above it, resulting in stratified combustion with a short interval from the fuel injection timing to the ignition timing. Therefore, the air-fuel mixture around the spark plug tends to be rich. Therefore, under the stratified low load operating condition where the air-fuel mixture around the spark plug tends to become rich, the ignition energy is increased compared to other operating conditions. Further, since the fuel injection amount increases as the load increases and the spark plug is likely to become rich, the ignition energy is increased as the load increases.

  Under stratified high-load operation conditions, stratified combustion is performed in which fuel is injected into the outer cavity to form a stratified mixture in the outer cavity and the volume above it, resulting in stratified combustion with a long interval from the fuel injection timing to the ignition timing. Therefore, the air-fuel mixture around the spark plug does not become richer than necessary. Therefore, under the stratified high load operation condition, the air-fuel mixture around the spark plug does not become unnecessarily rich, and it is not necessary to increase the ignition energy as compared with the stratified low load operation condition. Further, the stratified mixture field is set to be rich as the load increases, and the ignitability is improved. Therefore, the ignition energy is reduced as the load increases. However, in order to ensure ignitability, the ignition energy is set larger than that in the homogeneous operation condition.

Among the homogeneous operating conditions, an operating system that introduces a large amount of EGR, reduces pump loss due to throttling, and improves fuel efficiency is used under relatively low load operating conditions. In this case, in such a homogeneous mass EGR operating condition, the ignition energy is set to be larger than that in the homogeneous operating condition in which the mass EGR on the high load side is not introduced, for ignitability and combustion stability.
According to the present embodiment, stratified combustion in which the interval from the fuel injection timing to the ignition timing is shorter than a predetermined value (stratified combustion in which fuel is injected into the inner cavity and a stratified mixture is formed in the inner cavity and its upper volume) Since the air-fuel mixture around the spark plug tends to become rich, the ignition plug can be prevented from smoldering or misfiring by increasing the ignition energy. Further, in stratified combustion in which the interval from the fuel injection timing to the ignition timing is longer than the predetermined value (stratified combustion in which fuel is injected into the outer cavity and a stratified mixture is formed in the outer cavity and its upper volume) There is time for the spray to evaporate sufficiently, and the air-fuel mixture field does not become too rich around the spark plug. By not increasing the ignition energy more than necessary, fuel consumption deterioration due to electric load can be prevented, and the spark plug The durability of can be improved.

  Further, according to the present embodiment, stratified combustion (within the inner cavity and its empty volume) in which the interval between the fuel injection timing and the ignition timing is shorter than a predetermined value in the low load operating condition among the operating conditions for performing stratified combustion. Stratified combustion that forms a stratified mixture), and stratified combustion in which the interval between the fuel injection timing and the ignition timing is longer than the predetermined value under the high-load operation condition (the stratified mixture is formed in the outer cavity and in the upper volume thereof) By selecting the optimum stratified combustion method according to the load, it becomes possible to operate with good fuel efficiency at any load.

Further, according to the present embodiment, in the case of stratified combustion in which the ignition energy is increased, the ignition energy is increased as the load is higher, so that the air-fuel mixture around the spark plug becomes rich even at a load with a large injection amount. This prevents plug smoldering.
In addition, according to the present embodiment, in the case of stratified combustion that does not increase ignition energy, the load increases in the case of the stratified combustion method in which there is no fear of ignition smoldering by decreasing the ignition energy as the load is higher. At the same time, the fact that the stratified air-fuel mixture becomes rich and the ignitability is improved can be used to prevent fuel consumption deterioration due to an electric load and to improve the durability of the spark plug.

  Further, according to the present embodiment, a homogeneous mixture is formed in the entire combustion chamber to perform homogeneous combustion under a higher load operating condition than that in which stratified combustion is performed. By making the ignition energy equal to or smaller than that of stratified combustion without increasing energy. In the case of homogeneous combustion, there is no concern about spark plug smoldering compared to a stratified mixture field, and there is no problem with ignitability, so by not increasing ignition energy more than necessary, fuel consumption deterioration due to electric load can be prevented. The durability of the spark plug can be improved.

  Further, according to the present embodiment, a large amount of EGR gas is introduced and a large amount of EGR gas is introduced in the low load operation condition among the operation conditions for performing homogeneous combustion, as compared with the high load operation condition. In the case of homogeneous combustion, compared with the case of homogeneous combustion in which a large amount of EGR gas is not introduced, by increasing the ignition energy, the ignitability deteriorates in the case of a homogeneous operation method in which a large amount of EGR gas is introduced. Although there is a concern, combustion stability can be ensured by increasing ignition energy.

  Further, according to the present embodiment, the ignition energy when the engine operating condition is in the first operating region (stratified low load operating condition) is increased according to the increase in the load, while the engine operating condition is increased in the second operating region ( The ignition energy at the stratified high load operation condition) is decreased as the load increases, and the ignition energy at the lowest load in the first operating region is made larger than the ignition energy at the lowest load in the second operating region. This makes it possible to perform optimal control according to the increase or decrease of the load for each engine operating condition.

Next, a second embodiment of the present invention (corresponding to claims 1, 2, 5 to 13, particularly claims 5 and 6) will be described.
FIG. 7 is a configuration diagram (a cross-sectional view of the main part of the engine) of the second embodiment of the present invention, (A) is a front cross-sectional view, and (B) is a side cross-sectional view.
A significant difference from the first embodiment (FIG. 1) is the shape of the crown surface of the piston 3, which has a simple circular cavity 20 on the crown surface. Compared with the first embodiment (FIG. 1), the tip of the spark plug 12 protrudes greatly into the combustion chamber 4 so that the fuel spray from the fuel injection valve 11 can be directly ignited.

FIG. 8 shows the spray and gas mixture behavior under the stratified low load operation condition in the second embodiment. Under stratified low load operation conditions, the fuel injection timing is delayed. Immediately after being injected, the injected spray forms an air-fuel mixture field around it. Therefore, by setting the ignition timing immediately after injection, the air-fuel mixture field generated by the spray is directly ignited without using the cavity 20.
Also, under the stratified high-load operation condition, by accelerating the fuel injection timing, a stratified mixture is formed above the cavity 20 via the cavity 20, and ignited and burned.

FIG. 9 shows the relationship between the injection timing and the ignition timing in the second embodiment. Under the stratified low load operation condition, stratified combustion is performed without passing through the cavity, so that the injection timing and the ignition timing are set very close to each other. Further, in the stratified high load operation condition, since a stratified mixture field is used via the cavity, a certain interval is maintained between the injection timing and the ignition timing.
The relationship between the load (combustion method) and the ignition energy in the second embodiment is the same as in FIG.

  Under stratified low load operation conditions, stratified combustion is performed by directly forming a stratified mixture around the spark plug without passing through the cavity by fuel spray, and stratified combustion with a short interval from the fuel injection timing to the ignition timing results in a spark plug. The surrounding air-fuel mixture tends to be rich. Therefore, in the stratified low load operation condition where the air-fuel mixture around the spark plug tends to be rich, the ignition energy is increased as compared with other operation conditions. Further, since the fuel injection amount increases as the load increases and the spark plug is likely to become rich, the ignition energy is increased as the load increases.

  Under stratified high-load operation conditions, stratified combustion is performed by forming a stratified mixture around the spark plug through the cavity by fuel spray, and stratified combustion with a long interval from the fuel injection timing to the ignition timing is performed. The mixture does not become richer than necessary. Therefore, in the stratified high load operation condition, the air-fuel mixture around the spark plug does not become unnecessarily rich, so that it is not necessary to increase the ignition energy compared to the stratified low load operation condition. Further, the stratified mixture field is set to be rich as the load increases, and the ignitability is improved. Therefore, the ignition energy is reduced as the load increases. However, in order to ensure ignitability, the ignition energy is set larger than that in the homogeneous operation condition.

  In particular, according to the present embodiment, the stratified combustion that directly forms the stratified mixture around the spark plug without passing through the cavity by fuel spray (in other words, the mixture formed when the fuel spray reaches the spark plug directly) In stratified combustion in which ignition is performed, the air-fuel mixture around the spark plug tends to become rich. Therefore, smoldering and misfire of the spark plug can be prevented by increasing the ignition energy. Also, stratified combustion that forms a stratified mixture around the spark plug through the cavity by fuel spray (in other words, the fuel spray is induced through the cavity thereby igniting the mixture formed around the spark plug. In stratified combustion, the fuel spray does not evaporate sufficiently due to the piston crown surface temperature, and the air-fuel mixture field does not become too rich around the spark plug. It is possible to prevent deterioration of fuel consumption and improve the durability of the spark plug.

  In particular, according to the present embodiment, the stratified charge combustion that directly forms the stratified mixture around the spark plug by the fuel spray without passing through the cavity is performed under the low load operation condition among the operation conditions for performing the stratified charge combustion. By selecting the optimum stratified combustion method according to the load, by making the stratified combustion form a stratified mixture around the spark plug through the cavity by fuel spray under high load operating conditions, Driving with good fuel efficiency is possible.

Configuration diagram of the first embodiment of the present invention The figure which shows the spraying and gas mixture behavior in the stratified low load operation condition of 1st Embodiment The figure which shows the spraying and gas mixture behavior in the stratified high load operation condition of 1st Embodiment Illustration of ignition coil Illustration of ignition energy control The figure which shows the relationship between the load (combustion system) and ignition energy in this invention Configuration diagram of second embodiment of the present invention The figure which shows the spraying and gas mixture behavior in the stratified low load operation condition of 2nd Embodiment The figure which shows the relationship between the injection timing and ignition timing of 2nd Embodiment.

Explanation of symbols

1 Cylinder head
2 Cylinder block
3 Piston
4 Combustion chamber
5 Intake port
6 Exhaust port
7 Intake valve
8 Exhaust valve
9 Inlet valve cam
10 Exhaust valve cam
11 Fuel injection valve
12 Spark plug
13 Ignition coil
14 Inner cavity
15 Outer cavity
16 Control unit
20 cavities

Claims (13)

In a direct injection spark ignition internal combustion engine in which fuel is directly injected into the combustion chamber to form a stratified mixture around the ignition plug, and the stratified mixture is ignited by the ignition plug to perform stratified combustion.
As the stratified combustion, there are stratified combustion in which the interval from the fuel injection timing to the ignition timing is shorter than a predetermined value, and stratified combustion in which the interval from the fuel injection timing to the ignition timing is longer than the predetermined value,
In the stratified combustion where the interval from the fuel injection timing to the ignition timing is shorter than a predetermined value, the energy of ignition is increased compared to the stratified combustion where the interval from the fuel injection timing to the ignition timing is longer than the predetermined value. An ignition control device for a direct-injection spark-ignition internal combustion engine.   Of the operating conditions for performing stratified combustion, under low load operating conditions, stratified combustion is performed with the interval between the fuel injection timing and ignition timing shorter than a predetermined value, and under high load operating conditions, fuel injection timing and ignition timing 2. An ignition control device for a direct injection spark ignition type internal combustion engine according to claim 1, wherein the stratified charge combustion is performed with an interval between and a predetermined value longer than the predetermined value. In a direct injection spark ignition internal combustion engine in which fuel is directly injected into the combustion chamber to form a stratified mixture around the ignition plug, and the stratified mixture is ignited by the ignition plug to perform stratified combustion.
It has a fuel injection valve at the top of the combustion chamber, a double cavity inside and outside on the piston crown, a spark plug above the cavity,
As the stratified combustion, stratified combustion in which fuel is injected into the inner cavity to form a stratified mixture in the inner cavity and its upper volume, and fuel is injected into the outer cavity and stratified in the outer cavity and its upper volume. With stratified combustion to form a mixture,
In the stratified charge combustion that forms a stratified mixture in the inner cavity and its upper volume, the ignition energy is increased as compared with the stratified combustion that forms a stratified mixture in the outer cavity and its upper volume. An ignition control device for a direct injection spark ignition type internal combustion engine.   Of the operating conditions for performing stratified combustion, stratified combustion is performed to form a stratified mixture in the inner cavity and its upper volume under the low load operating condition, and in the outer cavity and its upper space under the high load operating condition. The ignition control device for a direct-injection spark-ignition internal combustion engine according to claim 3, wherein stratified combustion is performed to form a stratified mixture in the volume. In a direct injection spark ignition internal combustion engine in which fuel is directly injected into the combustion chamber to form a stratified mixture around the ignition plug, and the stratified mixture is ignited by the ignition plug to perform stratified combustion.
It has a fuel injection valve at the top of the combustion chamber, has a cavity on the piston crown, has a spark plug above the cavity,
The stratified combustion includes stratified combustion that directly forms a stratified mixture around the spark plug without passing through the cavity by fuel spray, and stratified combustion that forms a stratified mixture around the spark plug through the cavity by fuel spray. ,
Compared with stratified combustion, in which stratified mixture is formed directly around the spark plug by fuel spray without passing through the cavity, and compared with stratified combustion in which stratified mixture is formed around the spark plug through the cavity by fuel spray. An ignition control device for a direct-injection spark-ignition internal combustion engine characterized by increasing energy.   Of the operating conditions for performing stratified combustion, under low-load operating conditions, stratified combustion that directly forms a stratified mixture around the spark plug by fuel spray without passing through the cavity is performed. 6. The ignition control device for a direct injection spark ignition type internal combustion engine according to claim 5, wherein stratified combustion is performed by spraying to form a stratified mixture around the spark plug through the cavity.   In the case of stratified combustion in which the ignition energy is increased, the ignition energy is increased as the load is higher. The direct injection spark ignition internal combustion engine according to any one of claims 1 to 6, Ignition control device.   In the case of stratified combustion that does not increase the ignition energy, the ignition energy is reduced as the load is higher. The direct-injection spark-ignition internal combustion engine according to any one of claims 1 to 7, Ignition control device. In a higher-load operating condition than that in which stratified combustion is performed, a homogeneous mixture is formed in the entire combustion chamber to perform homogeneous combustion,
The direct-injection spark ignition according to any one of claims 1 to 8, wherein in homogeneous combustion, the ignition energy is equal to or smaller than that in stratified combustion that does not increase ignition energy. -Type internal combustion engine ignition control device.   Among the operating conditions for performing homogeneous combustion, a large amount of EGR gas is introduced at a low load operating condition compared to a high load operating condition, and a large amount of EGR is introduced in the case of homogeneous combustion in which a large amount of EGR gas is introduced. The ignition control device for a direct injection spark ignition type internal combustion engine according to claim 9, wherein the ignition energy is increased as compared with the case of homogeneous combustion without introducing gas. In a direct injection spark ignition internal combustion engine in which fuel is directly injected into the combustion chamber to form a stratified mixture around the ignition plug, and the stratified mixture is ignited by the ignition plug to perform stratified combustion.
The ignition energy when the engine operating condition is in the first operating region is increased according to the increase in the load, while the ignition energy when the engine operating condition is in the second operating region is decreased according to the increase in the load. An ignition control device for a direct-injection spark-ignition internal combustion engine.   The ignition control device for a direct injection spark ignition type internal combustion engine according to claim 11, wherein ignition energy at the lowest load in the first operating region is made larger than ignition energy at the lowest load in the second operating region.   The ignition control for a direct-injection spark-ignition internal combustion engine according to any one of claims 1 to 12, wherein the means for increasing the ignition energy is for increasing an energization time to the ignition coil. apparatus.

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