JP4492812B2 - In-cylinder injection internal combustion engine control device - Google Patents

Description

  The present invention relates to a control device for a direct injection internal combustion engine capable of injecting fuel into a combustion chamber.

In-cylinder injection internal combustion engines (hereinafter also referred to as engines) that inject fuel directly into the combustion chamber are operated with stratified combustion at a leaner air / fuel ratio than the stoichiometric air / fuel ratio, thereby reducing pumping loss and the like. Fuel consumption can be improved.
However, the operation at the lean air-fuel ratio has a problem that the exhaust gas temperature is low, the temperature of the exhaust gas purification catalyst provided in the exhaust passage is lowered, and the exhaust gas purification performance is deteriorated.

In the case of a conventional in-cylinder injection engine, when the catalyst temperature decreases in this way, the operation is switched from lean air-fuel ratio operation to operation in which uniform air-fuel ratio combustion is performed at a stoichiometric or rich air-fuel ratio. The exhaust temperature was raised and the exhaust purification performance was maintained.
However, if switching to stoichiometric or homogeneous mixed combustion at a rich air / fuel ratio each time the temperature of the catalyst decreases in this way, the operation time at the lean air / fuel ratio decreases, and the fuel efficiency improvement effect of the direct injection engine is reduced. There is a problem that it cannot be fully enjoyed.

Therefore, when the catalyst temperature becomes lower than the predetermined temperature, split injection is performed in which fuel injection is performed in the intake stroke and the compression stroke, and the ratio of the fuel injection amount in the compression stroke in the split injection is increased, thereby increasing the exhaust temperature. There is a technique for raising the catalyst temperature by raising the temperature (see Patent Document 1).
JP 2004-68624 A

In the technique disclosed in Patent Document 1, the ratio of the compression stroke injection amount is increased in order to increase the exhaust temperature in the split injection, but this reduces the amount of HC emission from the engine, and the amount of the exhaust gas on the exhaust purification catalyst. Since the reaction decreases, there is a problem that the effect of increasing the catalyst temperature is small.
Moreover, in the said patent document 1, the air fuel ratio is maintaining the stoichiometry, and cannot enjoy the fuel-consumption improvement effect by lean air fuel ratio driving | operation.

  The present invention has been made to solve such a problem, and the object of the present invention is to improve the fuel efficiency by lean air-fuel ratio operation and prevent the exhaust purification catalyst from lowering temperature and maintain the exhaust purification performance. It is an object of the present invention to provide a control device for a cylinder injection type internal combustion engine that can be used.

  In order to achieve the above object, in the control apparatus for a direct injection internal combustion engine according to claim 1, a fuel injection valve that directly injects fuel into the combustion chamber of the internal combustion engine, and a fuel injection amount that is injected from the fuel injection valve Provided in an exhaust passage of the internal combustion engine, a fuel injection amount control means for controlling the fuel, an ignition plug for igniting the fuel injected from the fuel injection valve, an ignition timing control means for controlling the ignition timing by the ignition plug, An exhaust purification catalyst having at least an oxidation function and purifying exhaust, catalyst temperature detecting means for detecting the temperature of the exhaust purification catalyst, and performing fuel injection during an intake stroke and a compression stroke of the internal combustion engine, An operation mode switching control means capable of selecting a split injection mode in which stratified combustion is performed at an air-fuel ratio leaner than the stoichiometric air-fuel ratio, and the fuel injection amount control means is configured to operate the catalyst during the split injection mode. With a decrease of the catalyst temperature detected by the degree detecting means, it is characterized by increasing the proportion of fuel injection quantity injected into the intake stroke relative proportions of the fuel injection amount injected in the compression stroke.

That is, in an internal combustion engine that includes an exhaust purification catalyst having an oxidation function in the exhaust passage and is capable of operating in the split injection mode in which fuel is injected in the intake stroke and the compression stroke at a lean air-fuel ratio, the exhaust purification is performed in the split injection mode. As the catalyst temperature of the catalyst decreases, the ratio of the fuel injection amount of the intake stroke injection is increased, that is, the ratio of the fuel injection amount of the compression stroke injection is decreased.
According to a second aspect of the present invention, there is provided a control device for a direct injection internal combustion engine according to the first aspect, wherein the ignition timing control means is ignited in response to a decrease in catalyst temperature detected by the catalyst temperature detection means in the split injection mode. It is characterized by retarding the timing.

That is, in the split injection mode, the intake stroke injection amount ratio is increased and the ignition timing is retarded according to the decrease in the catalyst temperature.
According to a third aspect of the present invention, there is provided a control device for an in-cylinder internal combustion engine, wherein the spark plug has an electrode portion disposed in or near a fuel injection path injected from the fuel injection valve. The ignition timing control means performs ignition when the fuel spray injected during the compression stroke passes through or near the electrode portion of the ignition plug in the divided injection mode. Yes.

That is, ignition is performed by a so-called spray guide method in which the fuel spray injected from the fuel injection valve is directly ignited.
According to a fourth aspect of the present invention, there is provided a control device for a cylinder injection type internal combustion engine, wherein the operation mode switching control means injects during the compression stroke at an air-fuel ratio that is leaner than a stoichiometric air-fuel ratio. A spray guide mode for igniting when fuel spray is passing in or near the electrode portion of the spark plug is selectable, and the catalyst temperature detected by the catalyst temperature detecting means is below a predetermined temperature. In this case, the divided injection mode is selected.

That is, if the catalyst temperature is equal to or lower than the predetermined temperature when operating at a leaner air-fuel ratio than the stoichiometric air-fuel ratio, the operation is performed in the split injection mode instead of the spray guide mode.
According to a fifth aspect of the present invention, the operation mode switching control means injects during the compression stroke at an air-fuel ratio that is leaner than the stoichiometric air-fuel ratio. A wall guide mode for igniting when fuel spray is guided by the cavity of the piston and reaches the vicinity of the electrode portion of the spark plug is selectable, and the catalyst temperature detected by the catalyst temperature detecting means is below a predetermined temperature. In this case, the divided injection mode is selected.

  That is, when the catalyst temperature is equal to or lower than the predetermined temperature when the operation is performed at the air-fuel ratio leaner than the stoichiometric air-fuel ratio, the operation is performed in the split injection mode instead of the wall guide mode.

According to the control apparatus for a direct injection internal combustion engine of the first aspect of the present invention using the above means, in the split injection mode of the lean air-fuel ratio operation, the fuel in the intake stroke according to the decrease in the catalyst temperature of the exhaust purification catalyst. By increasing the ratio of the injection amount, the amount of HC discharged from the internal combustion engine can be increased. Further, since it is a lean air-fuel ratio operation, the exhaust gas contains a large amount of O ₂ . As a result, a large amount of HC and O ₂ can be simultaneously supplied to the exhaust purification catalyst, the oxidation reaction on the exhaust purification catalyst can be promoted, and the catalyst temperature of the exhaust purification catalyst can be increased by the oxidation reaction heat. it can.

As a result, it is possible to prevent the temperature of the exhaust purification catalyst from decreasing and maintain the exhaust purification performance while improving the fuel efficiency by the lean air-fuel ratio operation.
According to the control apparatus for a cylinder injection internal combustion engine of claim 2, by increasing the intake stroke injection amount ratio and retarding the ignition timing in accordance with a decrease in the catalyst temperature in the split injection mode, In addition to raising the exhaust temperature, the HC emission amount can be further increased.

Thereby, the catalyst temperature of the exhaust purification catalyst can be increased more reliably.
According to the control apparatus for a cylinder injection type internal combustion engine of claim 3, since the fuel spray injected from the fuel injection valve is directly ignited, the split injection that is stable even in the low load low rotation speed region where the exhaust temperature is low. Operation in mode can be performed.
According to the control apparatus for a cylinder injection type internal combustion engine of claim 4, when the operation at the lean air-fuel ratio is performed, the operation in the split injection mode is performed when the catalyst temperature is equal to or lower than the predetermined temperature. While improving fuel efficiency, it is possible to prevent the exhaust purification catalyst from lowering temperature and maintain exhaust purification performance, and in situations where there is no catalyst temperature restriction, the spray guide mode can be used effectively to improve fuel efficiency. it can.

  According to the control apparatus for a cylinder injection internal combustion engine according to claim 5, when the operation at the lean air-fuel ratio is performed, the operation in the split injection mode is performed when the catalyst temperature is equal to or lower than the predetermined temperature. While improving fuel efficiency, it is possible to maintain the exhaust purification performance by preventing the temperature reduction of the exhaust purification catalyst, and in situations where there is no restriction on the catalyst temperature, the wall guide mode can be used effectively to improve fuel efficiency. it can.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
Referring to FIG. 1, there is shown a schematic configuration diagram of a control device for a direct injection internal combustion engine according to the present invention.
An engine 1 (internal combustion engine) shown in FIG. 1 is a four-cycle in-line four-cylinder engine, and FIG. 1 shows a longitudinal section of one of the cylinders. In addition, illustration and description are abbreviate | omitted as what has the same structure also about another cylinder.

As shown in FIG. 1, the engine 1 is configured by mounting a cylinder head 4 on a cylinder block 2.
A piston 8 is provided in a cylinder 6 formed in the cylinder block 2 so as to be slidable up and down.
A concave cavity 8 a is formed on the top surface of the piston 8.

Corresponding to the cylinder 6, so-called pent roof type inclined surfaces 10 a and 10 b are formed on the lower surface of the cylinder head 4, and are surrounded by the inclined surfaces 10 a and 10 b of the lower surface of the cylinder head 4, the cylinder 6 and the piston 8. A combustion chamber 12 is formed.
In the central portion of the upper wall of the combustion chamber 12, that is, in the central portion of the ridge line of both the slopes 10a and 10b, the fuel injection valve 14 is placed on one slope 10a, and the spark plug 16 is placed on the other slope 10b. It is provided in the face.

The fuel injection valve 14 is disposed slightly toward the electrode portion 16a side of the ignition plug 16 from the direction directly below, so that the fuel spray 18 injected from the fuel injection valve 14 is biased toward the ignition plug 16 side. It is configured.
In addition, the spark plug 16 is directed slightly toward the fuel injection valve 14 from directly below, and the electrode portion 16a is disposed so as to be located in the injection region of fuel injected from the fuel injection valve 14, that is, in the vicinity of the fuel spray 18. It is installed.

Further, two intake valves 20 are provided on one slope 10a on both sides of the fuel injection valve 14, and two exhaust valves are provided on the other slope 10b on both sides of the spark plug 16. Each valve 22 is provided.
The intake valve 20 and the exhaust valve 22 are configured to slide in the vertical direction so that the intake port 24 and the exhaust port 26 formed in the cylinder head 4 are connected to and disconnected from the combustion chamber 12, respectively.

The exhaust port 26 is connected to an exhaust pipe 30 via an exhaust manifold 28, and an exhaust purification catalyst 32 is provided in the exhaust pipe 30. The exhaust purification catalyst 32 is, for example, a three-way catalyst having a function of oxidizing HC and CO and reducing NOx.
The exhaust purification catalyst 32 is provided with a catalyst temperature sensor 34, and the catalyst temperature sensor 34 is electrically connected to an ECU (Electronic Control Unit) 40 mounted on the vehicle.

  The ECU 40 is also electrically connected to sensors such as an engine rotation speed sensor 42 that detects the engine rotation speed of the engine 1 and an accelerator opening degree sensor 44 that detects the accelerator opening degree. Based on this, the fuel injection timing and fuel injection amount control by the fuel injection valve 14 (fuel injection amount control means) and the ignition timing by the spark plug 16 are controlled (ignition timing control means), and according to the operating state of the engine 1. And a function of switching each operation mode of the uniform mixed combustion mode, the spray guide mode, the wall guide mode, and the divided injection mode (operation mode switching control means).

Here, in the uniform mixture combustion mode, fuel injection is performed during the intake stroke, so that fuel spray is mixed with intake air in advance and ignition is performed in a state where the combustion chamber 12 is made uniform in the vicinity of the stoichiometric air-fuel ratio. This is a combustion mode for burning.
The spray guide mode is an operation mode in which the fuel injection valve 14 injects fuel toward the electrode portion 16a of the spark plug 16 during the compression stroke, and ignites the fuel spray 18 that passes near the electrode portion 16a. . Note that the spray guide mode is an operation mode in which the fuel spray injected from the fuel injection valve 14 is directly ignited, so that stable combustion can be generated even in a low load low rotation speed region.

In the wall guide mode, fuel is injected during the compression stroke by the fuel injection valve 14, passes through the vicinity of the electrode portion 16a of the spark plug 16, and is guided by the shape of the cavity 8a of the piston 8 and rises in the vicinity of the electrode portion 16a. This is an operation mode in which the spray is ignited.
Further, in the split injection mode, after the fuel is injected during the intake stroke, the fuel is also injected during the compression stroke to stratify the vicinity of the plug spark plug 16 and the surrounding air-fuel ratio, and the fuel spray that passes through the vicinity of the electrode portion 16a. 18 is an operation mode in which ignition is performed. Similarly to the spray guide mode, the split injection mode is an operation mode in which the fuel spray injected from the fuel injection valve 14 is directly ignited, so that stable combustion can occur even in a low load and low rotation speed range. .

Note that the spray guide mode, the wall guide mode, and the split injection mode are all lean operation modes in which combustion is performed at a lean air-fuel ratio.
For example, when the exhaust temperature decreases due to the operation in the lean operation mode and the catalyst temperature of the exhaust purification catalyst 32 decreases, the ECU 40 performs the operation mode switching control according to the decrease in the catalyst temperature.

Hereinafter, specific control by the control device for a direct injection internal combustion engine according to the present invention configured as described above will be described.
First, a first embodiment in the control will be described.
In the ECU 40 according to the first embodiment, a first predetermined temperature T1, a second predetermined temperature T2, a third predetermined temperature T3, and a fourth predetermined temperature T4 are preset in order from the lowest temperature.

  In the split injection mode, two split injection modes are set according to the fuel injection amount ratio of the intake stroke injection and the compression stroke injection. Specifically, the first split injection mode in which the ratio of the fuel injection amount of the intake stroke injection is R1 (for example, 50%) and the ratio R2 (for example, 70%) of the fuel injection amount of the intake stroke injection is larger than R1. ) Is set as the second divided injection mode.

2 is a flowchart showing an operation mode switching control routine executed by the ECU 40 of the control device for the direct injection internal combustion engine according to the first embodiment of the present invention. Referring to FIG. FIG. 2 is a diagram showing the relationship between the catalyst temperature and the operation mode of the control device for a direct injection internal combustion engine according to the first embodiment of the present invention.
Hereinafter, it demonstrates along the flowchart of FIG.

First, in step S10, whether or not the operating state of the engine 1 satisfies the lean operation mode permission condition and whether or not the catalyst temperature T detected by the catalyst temperature sensor 34 is greater than the first predetermined temperature T1. Is determined.
Specifically, the engine rotation speed detected by the engine rotation speed sensor 42 is in a range greater than a preset permitted lower limit rotation speed and smaller than a permitted upper limit rotation speed, and the accelerator opening degree. The lean operation mode condition is satisfied when the load calculated from the accelerator opening detected by the sensor 44 and the engine speed is larger than the preset allowable lower limit load and smaller than the allowable upper limit load. It is.

When the determination result is false (No), that is, when the lean operation mode permission condition is not satisfied, or when the catalyst temperature T is equal to or lower than the first predetermined temperature T1, the process proceeds to step S11.
In step S11, the operation mode is set to the uniform mixed combustion mode, and the routine is returned.

On the other hand, if the determination result in step S10 is true (Yes), the process proceeds to step S12.
In step S12, it is determined whether or not the catalyst temperature T is lower than a fourth predetermined temperature T4. If the determination result is false (No), the process proceeds to step S13.
In step S13, the operation mode is set to the spray guide mode, and the routine is returned.

On the other hand, if the determination result in step S12 is true (Yes), the process proceeds to step S14.
In step S14, it is determined whether or not the catalyst temperature T is lower than the third predetermined temperature T3. If the determination result is false (No), the operation mode is set to the wall guide mode in step S15.

On the other hand, if the determination result in step S14 is true (Yes), the process proceeds to step S16.
In step S16, it is determined whether or not the catalyst temperature T is lower than the second predetermined temperature T2. If the determination result is false (No), the operation mode is changed to the first split injection mode in step S17. Set to.

On the other hand, if the determination result in step S16 is true (Yes), the process proceeds to step S18.
In step S18, the operation mode is set to the second split injection mode, and the routine returns.
That is, as shown in FIG. 3, the control switches the operation mode in the order of spray guide mode, wall guide mode, first split injection mode, second split injection mode, and uniform mixed combustion mode as the catalyst temperature decreases. It will be.

Generally, in the wall guide mode and the spray guide mode, the wall guide mode has a larger amount of HC emission, and the split injection mode has a larger amount of HC emission than the wall guide mode.
Here, referring to FIG. 4, there is shown a relational diagram showing the catalyst temperature, the exhaust temperature, and the HC emission amount from the engine 1 with respect to the ratio of the intake stroke injection amount in the split injection mode.

As shown in the figure, in the split injection mode, the exhaust gas temperature decreases as the intake stroke injection rate increases, while the HC emission increases.
Therefore, the control of the first embodiment switches to the operation mode with a large amount of HC emission as the catalyst temperature decreases.
When the amount of HC discharged from the engine 1 increases, a large amount of HC and O ₂ are supplied to the exhaust purification catalyst 32. The HC undergoes an oxidation reaction on the exhaust purification catalyst 32, and the exhaust purification catalyst 32 is heated by this oxidation reaction heat, and the catalyst temperature rises.

Furthermore, as shown in FIG. 4, the catalyst temperature of the exhaust purification catalyst 32 heated by the oxidation reaction heat is equal to or higher than the exhaust temperature, and the catalyst temperature can be raised higher than the heating by raising the exhaust temperature.
Thus, in the control apparatus for the direct injection internal combustion engine according to the first embodiment of the present invention, as the catalyst temperature decreases, the operation mode is switched to the operation mode with a large amount of HC emission while maintaining the lean operation mode. The oxidation reaction in the exhaust purification catalyst 32 can be activated, and the temperature of the catalyst can be raised by the oxidation reaction heat.

As a result, the operation time in the lean operation mode can be greatly extended, fuel efficiency can be improved, and the temperature reduction of the exhaust purification catalyst 32 can be prevented, and the exhaust purification performance can be maintained. .
In the ECU 40 in the first embodiment, a first predetermined temperature T1, a second predetermined temperature T2, a third predetermined temperature T3, and a fourth predetermined temperature T4 are preset in order from the lowest temperature.

In addition, in the divided injection mode in which the intake stroke injection and the compression stroke injection are performed, the first divided injection mode in which the ratio of the fuel injection amount injected in the intake stroke is R1 (for example, 50%) and the fuel injection amount of the intake stroke injection Is set to the second split injection mode in which R2 (for example, 70%) is larger than R1.
Next, a description will be given of a second embodiment of control by the control unit for a direct injection internal combustion engine according to the present invention.

  In the ECU 40 in the second embodiment, in the split injection mode, the fuel injection amount ratio of the intake stroke injection is set to R1 and the ignition timing is set to SA1 as in the first split injection mode. Is set. Similarly to the second split injection mode, a fourth split injection mode is set in which the fuel injection ratio of the intake stroke injection is R2, and the ignition timing is SA2, which is the ignition timing retarded from SA1. ing.

Referring to FIG. 5, an operation mode switching control routine executed by the ECU 40 of the control device for the direct injection internal combustion engine according to the second embodiment of the present invention is shown in a flowchart. A description of the same control as in the first embodiment is omitted.
Hereinafter, it demonstrates along the flowchart of FIG.
However, in the flowchart, steps S20 to S26 are the same as steps S10 to S16 in the flowchart of FIG. 2 in the first embodiment, and a description thereof will be omitted.

In the second embodiment, in step S26, it is determined whether or not the catalyst temperature T is lower than a second predetermined temperature T2. When the said determination result is false (No), it progresses to step S27 and sets to 3rd division | segmentation injection mode.
On the other hand, if the determination result of step S26 is true (Yes), the process proceeds to step S28, and the fourth divided injection mode is set.

As described above, in the control of the second embodiment, the operation mode is switched in the order of the spray guide mode, the wall guide mode, the third divided injection mode, the fourth divided injection mode, and the uniform mixed combustion mode as the catalyst temperature decreases. It will be.
Here, referring to FIG. 6, there is shown a relational diagram showing the catalyst temperature, the exhaust temperature, and the HC emission amount from the engine 1 with respect to the ignition timings in the split injection mode, the spray guide mode, and the wall guide mode.

  As shown in the figure, the split injection mode has a lower exhaust temperature than the spray guide mode and the wall guide mode, but the HC emission amount is relatively large, and the HC emission amount tends to increase as the ignition timing is retarded. It is in. In the spray guide mode and the split injection mode, since it is necessary to perform ignition during fuel injection, the ignition timing is retarded at the same time as the ignition timing is retarded here.

Therefore, the HC emission amount can be increased by switching to the third and fourth divided injection modes more than switching to the first and second divided injection modes.
As a result, the control apparatus for a direct injection internal combustion engine according to the second embodiment of the present invention can obtain the same effect as that of the first embodiment, and more reliably reduce the temperature of the exhaust purification catalyst 32. Therefore, exhaust purification performance can be maintained.

This is the end of the description of the embodiment of the control device for the direct injection internal combustion engine according to the present invention, but the embodiment is not limited to the above embodiment.
For example, in the above embodiment, as the catalyst temperature decreases, the spray guide mode, the wall guide mode, the split injection mode, and the uniform mixed combustion mode are set to be switched. This is because the HC emission is reduced as the catalyst temperature decreases. The setting is not limited to this combination as long as the operation mode is switched to the operation mode with a large amount. For example, a setting for not performing the spray guide mode, a setting for not performing the wall guide mode, or a setting for performing only the divided injection mode may be used.

Further, in the above embodiment, the intake stroke injection amount ratio in the split injection mode is set to two stages of R1 and R2. However, it may be set to any stage, and continuously according to the decrease in the catalyst temperature. It may be set to increase.
In the second embodiment, the ignition timing in the split injection mode is set to two stages, SA1 and SA2. However, it may be set to any stage, and continuously according to the decrease in the catalyst temperature. It may be set so as to be retarded.

Although the exhaust purification catalyst 32 is a three-way catalyst, the present invention can be applied to other catalysts as long as they have an oxidation function.
Further, in the above embodiment, the ignition in the split injection mode is a so-called spray guide method in which the fuel spray injected from the fuel injection valve 14 is directly ignited, but this may be any engine capable of stratified lean combustion, For example, a so-called wall guide system that ignites fuel spray guided by the cavity 8 a of the piston 8 may be used.

  In the above embodiment, the temperature of the exhaust purification catalyst 32 is detected by the catalyst temperature sensor 34. However, the catalyst temperature may be detected by estimating from the exhaust temperature or the like.

It is a schematic block diagram of the control apparatus of the cylinder injection type internal combustion engine which concerns on this invention. 3 is a flowchart showing an operation mode switching control routine executed by the ECU of the control device for the direct injection internal combustion engine according to the first embodiment of the present invention. FIG. 3 is a relationship diagram between a catalyst temperature and an operation mode of the control device for a direct injection internal combustion engine according to the first embodiment of the present invention. FIG. 5 is a relationship diagram showing catalyst temperature, exhaust temperature, and HC emission from the engine with respect to the ratio of the intake stroke injection amount in the split injection mode. It is a flowchart which shows the operation mode switching control routine performed by ECU of the control apparatus of the direct injection internal combustion engine which concerns on 2nd Example of this invention. FIG. 6 is a relationship diagram showing catalyst temperature, exhaust temperature, and HC emission amount from an engine with respect to ignition timings in a split injection mode, a spray guide mode, and a wall guide mode.

Explanation of symbols

1 engine (internal combustion engine)
DESCRIPTION OF SYMBOLS 14 Fuel injection valve 16 Spark plug 16a Electrode part 30 Exhaust pipe 32 Exhaust purification catalyst 34 Catalyst temperature sensor 40 ECU (fuel injection amount control means, ignition timing control means, operation mode switching control means)

Claims (5)

A fuel injection valve for directly injecting fuel into the combustion chamber of the internal combustion engine;
Fuel injection amount control means for controlling the fuel injection amount injected from the fuel injection valve;
A spark plug for igniting the fuel injected from the fuel injection valve;
Ignition timing control means for controlling the ignition timing by the spark plug;
An exhaust purification catalyst that is provided in an exhaust passage of the internal combustion engine and has at least an oxidation function and purifies exhaust;
Catalyst temperature detecting means for detecting the temperature of the exhaust purification catalyst;
An operation mode switching control means capable of selecting a split injection mode in which fuel injection is performed during an intake stroke and a compression stroke of the internal combustion engine, and stratified combustion is performed at an air-fuel ratio leaner than a stoichiometric air-fuel ratio;
In the split injection mode, the fuel injection amount control means injects into the intake stroke with respect to the ratio of the fuel injection amount injected in the compression stroke in response to a decrease in the catalyst temperature detected by the catalyst temperature detecting means. A control device for a direct injection internal combustion engine, wherein the ratio of the fuel injection amount to be increased is increased.   The in-cylinder injection internal combustion engine according to claim 1, wherein the ignition timing control means retards the ignition timing in accordance with a decrease in the catalyst temperature detected by the catalyst temperature detection means in the split injection mode. Engine control device. The spark plug has an electrode portion disposed in or near the fuel injection path injected from the fuel injection valve,
The ignition timing control means performs ignition when the fuel spray injected during the compression stroke passes through or near the electrode portion of the ignition plug in the split injection mode. The control apparatus for a direct injection internal combustion engine according to 1 or 2.   The operation mode switching control means is a spray that performs ignition when fuel spray injected during the compression stroke at an air-fuel ratio leaner than the stoichiometric air-fuel ratio passes through or near the electrode portion of the spark plug. The cylinder according to any one of claims 1 to 3, wherein a guide mode is selectable, and the split injection mode is selected when a catalyst temperature detected by the catalyst temperature detecting means is equal to or lower than a predetermined temperature. A control device for an internal injection type internal combustion engine.   The operation mode switching control means is a wall that performs ignition when fuel spray injected during the compression stroke at an air-fuel ratio leaner than the stoichiometric air-fuel ratio is guided by the piston cavity and reaches the vicinity of the electrode portion of the spark plug. The cylinder according to any one of claims 1 to 3, wherein a guide mode is selectable, and the split injection mode is selected when a catalyst temperature detected by the catalyst temperature detecting means is equal to or lower than a predetermined temperature. A control device for an internal injection type internal combustion engine.

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