CN100441839C - Direct Injection Spark Ignition Internal Combustion Engine - Google Patents

Abstract

When an engine is in transitional operation, combustion is carried out by spray guide method. Further, when catalyst temperature T is high, namely, equal to or higher than a specified maximum temperature T 1 stratified charge combustion by spray guide method is carried out, and when the catalyst temperature T is low, namely, equal to or lower than a specified minimum temperature T 2 , stratified charge combustion by wall guide method is carried out.

Description

Direct Injection Spark Ignition Internal Combustion Engine

technical field

The invention relates to a direct-injection spark ignition internal combustion engine, in particular to a technique for implementing stratified charge combustion by using a spray guiding method and a wall guiding method.

Background technique

In a direct-injection spark-ignition internal combustion engine in which fuel is directly injected into the combustion chamber, a technique called a spray-guiding method is known, in which the injector is installed in the central area of the upper wall of the combustion chamber and the spark plug is set Because the electrode part is located in or near the fuel injection area, stratified charge combustion can be implemented by directly igniting the fuel mist formed by the injector injection and partially vaporized fuel.

In stratified-charge lean combustion by this spray introduction method, especially in low-load operation, the fuel injection amount is small and the injection time is short, so that the time period in which ignition can be performed is short. Therefore, problems arise in that the stable combustion region is narrow and the stability of combustion is insufficient during low-load operation.

In order to implement stable stratified charge combustion in a direct-injection spark ignition internal combustion engine, the intake air flowing in through the intake port rises into a tumble flow and the fuel rises toward the tumble flow through a cavity formed on the top surface of the piston. The technology of side injection has been developed (Japanese Unexamined Patent Publication No. Hei 11-210472).

However, in the wall-guided method including the type using the tumble air flow, the combustion behavior (fuel injection timing, ignition timing, etc.) varies greatly depending on the engine speed and load of the internal combustion engine. Therefore, if the engine speed or load changes suddenly and unexpectedly, engine stalling can occur due to mismatched fuel injection timing, ignition timing, etc. Therefore, in order to maintain stable combustion, ordinary homogeneous charge combustion is usually carried out when the internal combustion engine is in a transition period.

As described above, although stratified charge combustion has advantages such as improvement in fuel economy, since it tends to be unstable depending on the operating state of the internal combustion engine, stratified charge combustion is only carried out under prescribed operating states.

In addition, in the spray-guided method, the oil mist gradually leaves the spark plug while moving, and the flame generated by the ignition of the spark plug spreads in the combustion chamber along with the oil mist. Thus, combustion proceeds relatively slowly. Therefore, the temperature of the exhaust gas is relatively low, which leads to a decrease in the conversion efficiency of the catalytic converter provided on the exhaust passage.

Contents of the invention

The present invention has been created to solve the above-mentioned problems. The object of the present invention is to provide a device that can stably implement stratified charge combustion according to the operating state of the internal combustion engine and can maintain the optimum temperature of the catalytic converter during the stratified charge combustion process so that the catalytic converter can realize a satisfactory exhaust gas purification function Direct injection spark ignition internal combustion engine.

In order to achieve the above objects, the present invention provides a direct-injection spark ignition internal combustion engine comprising an injector which injects fuel directly into the combustion chamber and which is mounted to the central region of the upper wall of the combustion chamber; A spark plug in or near a diffused fuel injection area; a cavity formed on the top surface of a piston near an electrode portion that guides fuel injected by an injector to a spark plug; an operating state detecting device that detects an operating state of an internal combustion engine; and controlling ignition timing of a spark plug The ignition timing control device, wherein the ignition timing control device controls the ignition timing depending on the operation state detected by the operation state detection device, at least during or immediately after fuel injection by the injector, or when the fuel injected by the injector passes through the The ignition is carried out when the cavity guide reaches the vicinity of the electrode portion.

In addition, the present invention provides a direct-injection spark ignition internal combustion engine comprising an injector installed in the central region of the upper wall of the combustion chamber for injecting fuel directly into the combustion chamber; The spark plug in or near the injection area; the cavity formed on the top surface of the piston that guides the fuel injected by the injector to the electrode portion of the spark plug; the conversion that is arranged in the exhaust passage connected to the combustion chamber Exhaust gas catalytic converter for harmful substances in the exhaust gas of the gas channel; catalyst temperature detection device for detecting the temperature of the exhaust gas catalytic converter; injection timing control device for controlling the injection timing of the injector; and ignition timing control device for controlling the ignition timing of the spark plug, which depends on Based on the temperature of the exhaust gas catalytic converter detected by the catalyst temperature detection device, the injection timing control device and the ignition timing control device can perform ignition during or immediately after fuel injection by the injector and in the fuel injected by the injector. A selection is made between modes of operation in which ignition is effected upon reaching the vicinity of the electrode portion guided through the cavity.

Description of drawings

The nature of the invention, together with other objects and advantages, will hereinafter be elucidated with reference to the accompanying drawings, in which like reference characters identify like or similar parts throughout, wherein:

1 is a schematic diagram showing a schematic structure of a direct injection spark ignition internal combustion engine according to the present invention;

Fig. 2 is a sectional view along line A-A in Fig. 1;

Figure 3 is a top view of the piston of Figure 1;

4 is a cross-sectional view of a combustion chamber showing the distribution of oil mist during fuel injection in a direct-injection spark ignition internal combustion engine according to the present invention;

Fig. 5 is a sectional view along line B-B in Fig. 4;

6 is a cross-sectional view of a combustion chamber showing the distribution of oil mist after fuel injection in a direct-injection spark ignition internal combustion engine according to the present invention;

Fig. 7 is a sectional view along line C-C in Fig. 6;

8A, 8B and 8C are graphs showing how the stable combustion regions of the spray guidance method and the wall guidance method change when the load state changes in the direct injection spark ignition internal combustion engine according to the present invention;

9A, 9B and 9C are graphs showing the exhaust gas characteristics of the direct injection spark ignition internal combustion engine according to the present invention when the spray guiding method is adopted and the wall guiding method is adopted;

FIG. 10 is a flowchart showing a control routine for determining the combustion method implemented by the ECU 50 in the direct injection spark ignition internal combustion engine according to the present invention.

Detailed ways

Embodiments of the present invention will be described below based on the drawings.

1 is a schematic diagram showing a schematic structure of a direct injection spark ignition internal combustion engine according to the present invention, FIG. 2 is a sectional view of a combustion chamber along line A-A in FIG. 1 , and FIG. 3 is a top view of a piston of FIG. 1 . The following description will be made based on FIGS. 1 to 3 .

As shown in Figure 1, the combustion chamber 2 of the engine 1 (internal combustion engine) consists of a cylindrical cylinder 4 formed in the cylinder block 3, a top surface of a piston 6 that can slide up and down in the cylinder 4, and a cylinder block 3 The bottom surface of the upper cylinder head 8 is defined.

The bottom surface of the cylinder head 8 forming the upper wall of the combustion chamber 2 has a so-called mono-pitched roof shape composed of two inclined surfaces 10a, 10b meeting at an obtuse angle.

The injector 12 is mounted to a slope 10a in the central region of the upper wall of the combustion chamber 2, and the spark plug 14 is mounted to the other slope 10b.

The injector 12 is arranged to inject fuel not directly downward but slightly toward the electrode portion 14 a of the spark plug 14 . In addition, the injector 12 is arranged so that the fuel injected by the injector 12 spreads more toward the side of the spark plug 14 .

Likewise, the spark plug 14 is arranged to generate a discharge not directly down but slightly towards the injector 12 . Further, the spark plug 14 is arranged such that the electrode portion 14a is located in or near a fuel injection region in which fuel injected by the injector 12 diffuses, or in other words, in or near the generated oil mist 15 .

On the side of the inclined plane 10 a, two intake valves 16 a, 16 b are arranged on opposite sides of the injector 12 . On the slope 10 b side, two exhaust valves 18 a , 18 b are provided on opposite sides of the spark plug 14 .

The intake valves 16a, 16b and the exhaust valves 18a, 18b are designed to slide up and down in the intake port 20 and the exhaust port 22 formed in the cylinder head 8 so that each intake port 20 or exhaust port 22 Connect and disconnect with combustion chamber 2.

In the following description, the plane containing the end of the injector 12 and the end of the spark plug 14 and extending inside the combustion chamber 2 will be referred to as plane P, the combustion chamber on which the injector 12 and the intake valves 16a, 16b are arranged. The slope 10a side of the combustion chamber 2 on which the spark plug 14 and the exhaust valves 18a, 18b are arranged will be referred to as the exhaust side.

A cavity 30 is formed on the top face of the piston 6 forming the bottom face of the combustion chamber 2 .

The cavity 30 is concave formed by a bottom surface 32 and a wall surface 34 .

Specifically, the bottom surface 32 of the cavity 30 generally slopes downward from the intake side to the exhaust side. The bottom surface 32 includes a raised portion 32 a higher than its surroundings, which extends along a plane P from near the center of the bottom surface 32 toward the wall surface 34 on the intake side. Thus, the raised portion 32a is surrounded by the recessed portion 32b, which is almost U-shaped when viewed from above.

As shown in FIG. 3 , the cavity 30 has opposite edges gradually approaching the plane P from the intake side to the exhaust side, so that the opening of the cavity becomes narrower from the intake side to the exhaust side.

The wall surface 34 of the cavity 30 slopes upward smoothly from the periphery of the bottom surface 32 .

The exhaust port 22 is connected to an exhaust pipe 42 (exhaust passage) through an exhaust manifold 40 . An exhaust catalytic converter 44 is provided in the exhaust pipe 42 . The exhaust catalytic converter 44 is, for example, a three-way catalytic converter capable of oxidizing HC and CO and reducing NOx.

A catalyst temperature sensor 46 (catalyst temperature detection means) is attached to the exhaust gas catalytic converter 44 . The catalyst temperature sensor 46 is electrically connected to an ECU (Electronic Control Unit) 50 (injection timing control device, ignition timing control device).

The ECU 50 also cooperates with an APS (accelerator position sensor) 52 (running state detection device) that detects the depression of the accelerator pedal, a TPS (throttle position sensor) 54 (running state detection device) that detects the throttle opening, and an engine that detects the rotational speed of the engine 1 . A rotational speed sensor 56 (operating state detecting means), a vehicle speed sensor 58 (operating state detecting means) detecting a vehicle speed, and various devices including the injector 12 and the spark plug 14 are electrically connected and perform various controls.

Hereinafter, it will be explained how the direct injection type spark ignition internal combustion engine according to the present invention having the above structure works.

Fig. 4 is a cross-sectional view of a combustion chamber, showing the distribution of oil mist during fuel injection in a direct-injection spark ignition internal combustion engine according to the present invention; Fig. 5 is a cross-sectional view along line B-B in Fig. 4; Fig. 6 is similar to Fig. 4 A cross-sectional view showing the distribution of air-fuel mixture formed by fuel vaporization after fuel injection in a direct-injection spark ignition internal combustion engine according to the present invention; and FIG. 7 is a cross-sectional view along line C-C in FIG. 6 . The following description will be made based on FIGS. 4 to 7 .

As shown in FIGS. 4 and 5, fuel is injected from the tip of the injector 12 toward the side of the spark plug 14 when the piston 6 is in the post compression stroke. The injected fuel passing near the electrode portion 14 a of the spark plug 14 and entering the cavity 30 in the top surface of the piston 6 becomes oil mist 15 mainly on the exhaust side. Here, the ideal configuration is to make the oil mist 15 formed by the fuel injection of the injector 12 distributed in a hollow shape, for example, a hollow conical distribution, but of course it is not limited to this distribution.

Since the bottom surface 32 of the cavity 30 slopes downward from the intake side to the exhaust side and the oil mist 15 diffuses more toward the spark plug 14 side, the oil mist that has entered the cavity 30 and collides with the bottom surface 32 of the cavity 30 The 15 is directed to the exhaust side in a good way while being more vaporized. Here, the oil mist 15 that has collided with the rising portion 32a of the bottom surface 32 is diffused to both sides of the rising portion 32a and the exhaust side. Then, as shown in FIGS. 6 and 7 , the oil mist 15 guided along the wall surface 34 on the exhaust side moves upward while being further vaporized and leaves the cavity 30 as an air-fuel mixture 15 a.

The air-fuel mixture 15 a that has thus escaped from the cavity 30 curves up and surrounds the electrode part 14 a of the spark plug 14 . As a result, there is a relatively rich air-fuel mixture around the electrode portion 14a.

Specifically, since the oil mist 15 having a hollow shape distribution in the combustion chamber 2 is diffused to both sides by the rising portion 32a of the bottom surface 32 of the cavity 30, moves to the periphery of the bottom surface 32 and rises in a curve, so in its central area The resulting air-fuel mixture contains a lower amount of fuel. In this way, the air-fuel mixture 15a does not become too rich around the electrode portion 14a.

Assuming that the fuel is injected by the injector 12 in the manner described above, two ignition methods can be envisaged: the so-called spray-guided method in which the oil mist 15 formed during fuel injection is directly ignited as shown in FIGS. The so-called wall-guided method in which the air-fuel mixture 15a shown in and 7 which has escaped from the cavity 30 and collected around the electrode portion 14a is ignited. As for the wall guide method, the type in which the air-fuel mixture is guided around the electrode portion 14a not depending on the intake flow such as the tumble flow but based on the fuel injection force is best. This is because the tumbling airflow formed by the intake air is relatively weak and depends on the change of the operating state of the engine, so it is not enough to guide the oil mist to achieve stable stratified charge combustion.

Fig. 8 is a graph showing how the stable combustion regions of the spray guiding method and the wall guiding method change when the load state changes in the direct injection spark ignition internal combustion engine according to the present invention; Graph of exhaust gas characteristics of a direct-injection spark-ignition internal combustion engine according to the invention when the method is employed. Features of the spray guidance method and the wall guidance method will be explained based on FIGS. 8 and 9 .

8A, 8B, and 8C show the stable combustion regions of the spray-guided method and the wall-guided method at low load, medium load, and high load, respectively, where the ignition timing is represented by the vertical axis and the injection timing is represented by the horizontal axis.

As can be seen from these figures, with the wall-guided method, the stable combustion area changes when the load changes. Therefore, in the wall-guided method, the injection timing and the ignition timing must be changed depending on the rotation speed and the load of the engine 1 during the transition period of the load change.

Meanwhile, with respect to the spray guiding method, since ignition is performed during or immediately after fuel injection by the injector 12, the stable combustion area remains relatively constant regardless of load changes. Therefore, the engine can be operated with constant fuel injection timing and ignition timing regardless of the rotation speed and load of the engine 1 .

Therefore, the spray-guided method is characterized by stable combustion during the transition period.

9A, 9B and 9C show the HC emission amount, NOx emission amount and CO emission amount, respectively, wherein each emission amount is indicated by the vertical axis and the injection timing is indicated by the horizontal axis.

From these figures it can be seen that the wall-guided method is characterized by producing more HC emissions, more CO emissions and less NOx emissions compared to the injection-guided method.

FIG. 10 is a flowchart showing a control routine for determining the combustion method implemented by the ECU 50 in the direct injection spark ignition internal combustion engine according to the present invention. The following description will be based on this flowchart.

First, in step S1, various detection data are read, including the engine speed N from the engine speed sensor 56, the accelerator depression Acc from the APS52, the throttle opening θ from the TPS54, the vehicle speed V from the vehicle speed sensor 58, the The catalyst temperature T of the catalyst temperature sensor 46 .

Then in step S2, it is determined whether the operating state of the engine 1 satisfies the condition of stratified charge combustion based on the engine speed N and the engine load L calculated from the throttle opening θ. Specifically, determine whether the engine speed N is smaller than the predetermined maximum engine speed N1 of stratified charge combustion and whether it is greater than the predetermined minimum engine speed N2 of stratified charge combustion (N2<N<N1), and determine whether the engine load L Whether it is less than the predetermined maximum load L1 of stratified charge combustion and whether it is greater than the predetermined minimum load L2 of stratified charge combustion (L2<L<L1). If the result of the determination in step S2 is negative (No), step S20 is adopted to implement homogeneous charge combustion and the implementation of the routine ends here. If the result of the determination in step S2 is Yes (Yes), step S3 is adopted.

In step S3, the engine 1 is determined by determining whether the change of the engine speed per unit time |ΔN|, the change of the vehicle speed per unit time |ΔV|, and the change of the throttle opening per unit time |Δθ| are less than the predetermined values determined for them. Is it running stably. If the result of the determination in step S3 is negative (No), that is, the engine 1 is in a transient operation in which the change in any one of the engine speed N, the vehicle speed V and the throttle opening θ per unit time is a prescribed value or more state, step S10 is adopted to carry out combustion by means of spray guidance and the execution of the program ends here. At this time, even if the engine 1 is in a transient operation state, stratified charge combustion can be stably carried out.

Meanwhile, if the result of the determination in step S3 is Yes (Yes), that is, the engine 1 is in a steady running state, step S4 is adopted.

In step S4, it is determined whether or not the catalyst temperature T is lower than a predetermined maximum prescribed temperature T1 (second prescribed temperature). If the result of the determination in step S4 is negative (No), that is, the temperature T of the catalyst is high, ie, equal to or higher than the maximum specified temperature T1, step S10 is adopted to carry out combustion by the spray induction method. As such, by performing combustion using the spray-guided method when the catalyst temperature is high, HC emissions and CO emissions can be reduced, so that a rise in catalyst temperature, and catalyst deterioration and catalyst poisoning due to oxidation can be suppressed.

Meanwhile, if the determined result in step S4 is Yes (Yes), step S5 is taken. In step S5, it is determined whether the catalyst temperature T is higher than a predetermined minimum prescribed temperature T2 (first prescribed temperature). If the result of determination in step S5 is negative (No), that is to say the temperature T of the catalyst is low, that is, equal to or lower than the minimum specified temperature T2, step S8 is adopted to carry out combustion by the wall-guided method and the execution of the program ends here . Like this, by performing combustion by employing the wall-guiding method when the catalyst temperature is low, the HC emission amount and the CO emission amount can be increased, the catalytic oxidation reaction can be promoted, and the heat generated in the oxidation reaction can cause the temperature of the catalyst to rise, Thereby stimulating the exhaust gas purification function.

Meanwhile, if the determined result in step S5 is Yes (Yes), step S6 is taken.

In step S6, it is determined whether or not a predetermined time (for example, 2 seconds) has elapsed after the condition for recognizing stable operation in the above-mentioned step S3 is satisfied. If the result of the determination in step S6 is negative (No), step S1 is adopted again. If the result of the determination in step S6 is Yes (Yes), ie a period of time has elapsed after the engine has been in a steady state, step S7 is adopted.

In step S7, it is determined based on the engine speed N and the engine load L whether the operating state of the engine 1 satisfies the conditions of the wall guidance method. Specifically, whether the engine speed N is less than the predetermined maximum engine speed N3 of stratified charge combustion and whether it is greater than the predetermined minimum engine speed N4 of stratified charge combustion (N4<N<N3), and determine whether the engine load L is less than Whether the predetermined maximum engine load L3 of stratified charge combustion is greater than the predetermined minimum engine load L4 of stratified charge combustion (L4<L<L3). If the result of the determination in step S7 is yes (Yes), the combustion is carried out by the wall-guided method with step S8 and the execution of the program ends here. Meanwhile, if the result of the determination in step S7 is negative (No), the combustion is carried out by the spray induction method using step S10 and the execution of the routine ends here. .

As mentioned above, when the operating state of the engine 1 satisfies the condition of stratified charge combustion and the engine 1 is in the transient operation period, the combustion is carried out by the spray guiding method, and stable combustion which is not easily affected by the change of the engine speed N and the engine load L can be achieved.

In addition, when the engine 1 is in a steady state, switching between the spray guidance method and the wall guidance method is carried out by selecting the better one of fuel economy and the like depending on the engine speed N and the load L. Switching between the spray-guided method and the wall-guided method is carried out depending on the catalyst temperature T, so that the exhaust gas catalytic converter 44 is always at an optimum temperature, so that the exhaust gas catalytic converter can satisfactorily perform the function of exhaust gas purification. As a result, harmful substances contained in exhaust gas can be sufficiently reduced.

In addition, even if ignition by the spray-introduction method fails or the flame accidentally stops spreading after ignition by the spray-introduction method, continued ignition and combustion by the wall-introduction method can eventually be completed.

Specifically, in the direct-injection spark ignition internal combustion engine according to the invention, the wall-guided method can be implemented only by retarding the ignition timing compared to the spray-guided method. Therefore, for example, by providing misfire detection means, it is possible to easily configure that even if ignition fails by the spray-guided method, misfire is detected and ignition is completed by the wall-guided method soon thereafter.

It can also be configured to implement a so-called double ignition, where ignition by the spray-guided method is followed by an ignition by the wall-guided method whenever combustion is carried out by the spray-guided method.

In this way, the stable combustion area can be enlarged, so that the stability of stratified charge combustion can be further improved.

The above is the description of the direct injection type spark ignition internal combustion engine which is one embodiment of the present invention. However, the present invention is not limited to the above-described embodiments.

For example, in the above embodiments, the combustion method to be employed is determined based on the operating state of the engine 1 and the catalyst temperature. However, the determination may be based on only one of these factors, or additional factors may also be considered in determining the combustion method to be employed.

Furthermore, in the above embodiment, the APS 52, the TPS 54, the engine speed sensor 56 and the vehicle speed sensor 58 are used as the running state detection means. However, the operating state detection device is not limited to these devices. The operating state of the engine 1 can be detected from other factors by using other means.

Furthermore, in the above embodiments, the exhaust gas catalytic converter 44 is a three-way catalytic converter. However, the exhaust catalytic converter is not limited thereto and may be of other types.

The invention thus described herein, it will be obvious that the invention may be varied in many ways. Such changes are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to a person skilled in the art are intended to be included within the scope of the appended claims.

Claims (12)

1. A direct-injection spark ignition internal combustion engine, characterized in that the internal combustion engine comprises: Injectors installed in the central area of the upper wall of the combustion chamber to inject fuel directly into the combustion chamber; a spark plug provided with an electrode portion located in or near a fuel injection region in which fuel injected by the injector diffuses; A cavity formed on the top surface of the piston that guides the fuel injected by the injector to the vicinity of the electrode portion of the spark plug; an operating state detecting device for detecting an operating state of the internal combustion engine indicating a stable operating state of the internal combustion engine; and an ignition timing control device for controlling the ignition timing of the spark plug; wherein The ignition timing control means controls the ignition timing according to the operating state detected by the operating state detecting means, so that at least when the injector is injecting fuel or just after the fuel is injected, or when the fuel injected by the injector reaches the vicinity of the electrode part through the guidance of the cavity Implement ignition. 2. The direct-injection spark ignition internal combustion engine as claimed in claim 1, characterized in that, The ignition timing control means controls the ignition timing so that when the unstable operation state of the internal combustion engine is detected by the operation state detection means, ignition is performed by the spark plug during or immediately after fuel injection from the injector. 3. The direct-injection spark ignition internal combustion engine as claimed in claim 1, wherein the internal combustion engine further comprises: a flameout detecting device for detecting flameout occurring in the combustion chamber, wherein The ignition timing control device controls the ignition timing so that the injector performs ignition during or immediately after fuel injection, and if the misfire detection device detects misfire during ignition, the air-fuel mixture formed by more vaporized fuel Ignition is carried out when guided through the cavity to the vicinity of the electrode portion. 4. The direct injection spark ignition internal combustion engine as claimed in claim 1, wherein The ignition timing control device controls the ignition timing so that no matter when the fuel is injected by the injector or immediately after the fuel is injected, the air-fuel mixture formed by the injector and more vaporized fuel passes through the cavity Ignition is carried out when the guide reaches the vicinity of the electrode portion. 5. A direct-injection spark ignition internal combustion engine, characterized in that the internal combustion engine comprises: The fuel injector installed in the central area of the upper wall of the combustion chamber to inject fuel directly into the combustion chamber; a spark plug provided with an electrode portion located in or near a fuel injection region in which fuel injected by the injector diffuses; A cavity formed on the top surface of the piston that guides the fuel injected by the injector to the vicinity of the electrode portion of the spark plug; an exhaust gas catalytic converter provided on the exhaust passage connected to the combustion chamber for converting harmful substances contained in the exhaust gas flowing through the exhaust passage; A catalyst temperature detection device for detecting the temperature of the exhaust gas catalytic converter; An operation state detection device for detecting the operation state of the internal combustion engine indicating the stable operation state of the internal combustion engine; an injection timing control device that controls the injection timing of the injectors; and An ignition timing control device for controlling the ignition timing of the spark plug; wherein, When the running state detection device detects the stable running state of the internal combustion engine, the injection timing control device and the ignition timing control device can detect the temperature of the exhaust gas catalytic converter according to the temperature of the exhaust gas catalytic converter detected by the catalyst temperature detection device. A selection is made between a first operation mode in which ignition is performed later and a second operation mode in which ignition is performed when fuel injected from the injector is guided through the cavity to reach the vicinity of the electrode portion. 6. The direct-injection spark ignition internal combustion engine as claimed in claim 5, characterized in that, When the temperature of the exhaust gas catalytic converter detected by the catalyst temperature detection device is equal to or lower than the first specified temperature, the injection timing control device and the ignition timing control device select when the fuel injected by the injector is guided through the cavity and reaches the vicinity of the electrode part. The mode of operation of the ignition. 7. The direct-injection spark ignition internal combustion engine as claimed in claim 6, characterized in that, When the temperature of the exhaust gas catalytic converter detected by the catalyst temperature detection device is equal to or higher than the second predetermined temperature higher than the first predetermined temperature, the injection timing control device and the ignition timing control device select the period during which the injector injects fuel or immediately after the fuel is injected. An operation mode in which ignition is performed after injection. 8. The direct-injection spark ignition internal combustion engine as claimed in claim 5, characterized in that, the internal combustion engine further comprises: a flameout detection device for detecting flameout in the combustion chamber, wherein, The ignition timing control device controls the ignition timing so that ignition is carried out during or immediately after fuel injection from the injector, and if the misfire detection device detects misfire at the time of ignition, the air-fuel mixture formed by more vaporized fuel Ignition is carried out when guided through the cavity to the vicinity of the electrode portion. 9. The direct injection spark ignition internal combustion engine as claimed in claim 5, characterized in that, The ignition timing control device controls the ignition timing so that regardless of whether ignition is carried out during fuel injection by the injector or immediately after fuel injection, the air-fuel mixture injected by the injector and formed from more vaporized fuel is guided through the cavity to reach the electrode portion Ignite when nearby. 10. The direct injection spark ignition internal combustion engine as claimed in claim 1, characterized in that, The operating state detection means determines that the internal combustion engine is in a steady operating state when at least one of a change in engine speed, a change in vehicle speed, and a change in throttle opening is within a prescribed value. 11. The direct injection spark ignition internal combustion engine as claimed in claim 10, characterized in that, The operating state detecting means determines that the internal combustion engine is in a stable operating state when the variation of the engine speed is within the first predetermined value, the variation of the vehicle speed is within the second predetermined value, and the variation of the throttle opening is within the third predetermined value. 12. The direct injection spark ignition internal combustion engine as claimed in claim 5, characterized in that, When the temperature of the exhaust gas catalytic converter detected by the catalyst temperature detection device is between the first specified temperature and the second specified temperature, the injection timing control device and the ignition timing control device operate in the first operation mode and the second operation mode based on the engine speed and engine load. Choose between operating modes.

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