JP2007002794A - Controller for cylinder direct injection type spark ignition internal combustion engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To substantialize early activation of a catalyst and HC reduction due to after-burning by drastic delay of ignition timing, and to avoid thermal damage of a catalyst converter due to a rapid temperature rise. <P>SOLUTION: At cold start of an internal combustion engine requiring early temperature rise of a catalytic convertor, ignition timing is set after a compression top dead center, and super retard combustion for injecting fuel before the ignition timing and after the compression top dead center is performed. Since turbulence inside a cylinder is improved due to high-pressure fuel injection immediately before the ignition timing and flame spread is promoted, stable combustion can be realized. In super retard combustion, a high exhaust temperature can be obtained, and when the exhaust temperature is raised immediately after cold start, thermal distortion of the catalyst converter is increased. Therefore, until the catalyst temperature reaches the activation start temperature, the top dead center injection operation mode is prohibited. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an in-cylinder direct injection type spark ignition internal combustion engine that directly injects fuel into a cylinder, and in particular, at a cold start in which early temperature rise (early activation) of an exhaust system catalytic converter is required. It relates to control of injection timing and ignition timing.

In Patent Document 1, as a catalyst warm-up method for a direct injection spark-ignition internal combustion engine, a period from the intake stroke to the ignition timing when the exhaust gas catalytic converter is in an unwarmed state lower than the activation temperature. In this case, it is possible to spread the fuel by the late injection in which the air-fuel mixture having a partial air-fuel ratio concentration is formed in the combustion chamber, the fuel is injected before this late injection, and the fuel of the late injection and the combustion of the late injection And at least two split injections of early injection for generating an air-fuel mixture leaner than the stoichiometric air-fuel ratio in the combustion chamber, and retarding the ignition timing by a predetermined amount from the MBT point, and no engine load A technique is described in which the ignition timing is set before the compression top dead center in the region, and the ignition timing is retarded until the compression top dead center in the low speed and low load region excluding the no-load region. The latter-stage injection is performed after the middle of the compression stroke, for example, at 120 ° BTDC to 45 ° BTDC.
Japanese Patent No. 3325230

  For early activation of the catalyst when the internal combustion engine is cold and HC reduction due to afterburning, retarding the ignition timing is effective. To obtain a greater effect, ignition after compression top dead center (ATDC) Ignition) is desirable. In order to perform stable combustion by ATDC ignition, it is necessary to shorten the combustion period. For this reason, it is necessary to increase the combustion speed (flame propagation speed) by strengthening the turbulence in the cylinder.

  In order to strengthen such disturbance, it is conceivable that the disturbance is generated in the cylinder by the energy of the fuel spray injected at a high pressure in the cylinder.

  However, in Patent Document 1, the first fuel injection (early injection) is performed during the intake stroke, and the second fuel injection (late injection) is performed from 120 ° BTDC to 45 ° BTDC during the compression stroke. Yes. As described above, before the last fuel injection is before the compression top dead center, even if the spray generates turbulence in the cylinder, the turbulence is attenuated after the compression top dead center, and the flame propagation in ATDC ignition Does not contribute to speed increase.

  For example, FIG. 9 shows the magnitude of turbulence in the cylinder when a gas flow control valve (for example, a tumble control valve) provided in the intake port is operated and when such a gas flow control valve is not provided. As shown, the turbulence (part A) generated during the intake stroke by operating the gas flow control valve is attenuated as the compression stroke progresses, and is temporarily accompanied by the collapse of the tumble flow in the latter half of the compression stroke. Although the turbulence increases (the portion indicated by reference symbol B), after the compression top dead center, as shown by the reference symbol C, it rapidly attenuates, and combustion improvement (improving flame propagation) using the turbulence cannot be expected so much. The same applies to turbulence caused by fuel spray, and even if turbulence is generated by fuel injection before compression top dead center, it does not contribute to ignition combustion after compression top dead center.

  For this reason, ATDC ignition is more advantageous for increasing exhaust temperature and reducing HC, but combustion stability is not established. Therefore, in Patent Document 1, the ignition timing is set to before compression top dead center (BTDC ignition) in the no-load region. Yes.

  The present invention aims to improve the combustion stability in ATDC ignition for early activation of the catalyst, reduction of HC, and the like based on such a situation.

  The present invention provides a control device for an in-cylinder direct injection spark ignition internal combustion engine that includes a fuel injection valve that directly injects fuel into a cylinder and that includes an ignition plug. When the exhaust gas temperature needs to be raised, such as when the engine is cold, the ignition timing is set after the compression top dead center, and super retard combustion is performed to inject fuel before the ignition timing and after the compression top dead center. It is characterized by that. In the NOx trap catalyst that adsorbs NOx, the sulfur component (SOx) adheres to the catalyst, so that the NOx adsorption performance deteriorates. Therefore, the SOx release treatment (sulfur coating) that forcibly increases the temperature of the catalyst and releases SOx. However, it is also possible to raise the temperature of the exhaust gas during the SOx release process using the above-mentioned super retard combustion. In the present invention, the super retard combustion is prohibited particularly while the catalytic converter provided in the exhaust system is in a predetermined low temperature state.

  In other words, after the compression top dead center, the turbulence generated in the intake stroke and the compression stroke is attenuated, but the in-cylinder turbulence is generated and strengthened by the fuel injection performed during the expansion stroke after the compression top dead center. Flame propagation with ATDC ignition is facilitated. Therefore, super retard combustion with the ignition timing after the compression top dead center is established stably.

  Here, in the super retard combustion in which the ignition timing is greatly retarded as described above, the exhaust temperature becomes very high as compared with the conventional technology such as Patent Document 1, so that the catalytic converter is completely If the engine is in a cold state (close to the outside air temperature) and if the engine is shifted to super retarded combustion immediately after the engine is started, the temperature gradient inside the catalytic converter becomes very steep. That is, there is a concern that only the upstream portion such as the monolithic ceramic catalyst carrier rapidly becomes high in temperature and the thermal strain increases.

  Therefore, in the present invention, the super retard combustion is prohibited while the catalytic converter provided in the exhaust system is in a predetermined low temperature state.

  In one embodiment of the present invention, the super retard combustion is prohibited until the catalytic converter reaches the start of catalytic activity. If the catalytic activity starts even slightly, the catalytic converter tries to increase the temperature from the inside due to the exothermic reaction, so even if the temperature of the exhaust gas flowing from the upstream to the catalytic converter becomes very high, the temperature gradient of the catalytic converter is It will be moderate.

  In one aspect of the present invention, the super retard combustion is prohibited until the exhaust temperature at the outlet of the catalytic converter reaches a predetermined temperature. Since the temperature change at the outlet of the catalytic converter occurs later than the temperature change of the carrier of the catalytic converter, it can be considered that the temperature of the entire catalytic converter has risen uniformly to some extent when it becomes high to some extent. Therefore, even if the exhaust temperature rapidly rises as super retard combustion, excessive thermal distortion is not caused.

  Further, in one aspect of the super retard combustion according to the present invention, fuel injection is further performed during the intake stroke or the compression stroke prior to the fuel injection after the compression top dead center. That is, fuel injection is performed in substantially divided two times. Then, at the start of super retard combustion, the injection timing of the second fuel injection is gradually retarded to a predetermined injection timing so that the exhaust gas temperature gradually increases. This prevents a sudden rise in exhaust gas temperature.

  According to the present invention, it is possible to sufficiently ensure the combustion stability of the super retard combustion in which the ignition timing is set after the compression top dead center. For example, at the time of cold start, the catalyst is activated early and the HC due to the afterburning. Reduction can be achieved. Then, since the exhaust gas temperature starts to rise rapidly from a state where the catalytic converter is warmed to some extent, thermal deterioration due to an extreme temperature gradient of the catalytic converter can be avoided.

  Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a configuration explanatory view showing a system configuration of a direct injection type spark ignition internal combustion engine to which the present invention is applied.

  An intake passage 4 is connected to the combustion chamber 3 formed by the piston 2 of the internal combustion engine 1 via an intake valve (not shown), and an exhaust passage 5 is connected via an exhaust valve (not shown). Has been. The intake passage 4 is provided with an air flow meter 6 for detecting the amount of intake air, and an electronically controlled throttle valve 7 whose opening degree is controlled via an actuator 8 by a control signal. The exhaust passage 5 is provided with a catalytic converter 10 for purifying exhaust gas, and air-fuel ratio sensors 11 and 12 are provided on the upstream side and the downstream side, respectively. Further, the upstream air-fuel ratio sensor 11 is provided. Is provided with an exhaust gas temperature sensor 13 for detecting the exhaust gas temperature at the inlet side of the catalytic converter 10. Further, in the present embodiment, in order to detect the temperature state of the catalytic converter 10, a catalyst temperature sensor 31 disposed at the center in the longitudinal direction of the monolithic ceramic catalyst carrier of the catalytic converter 10 and an outlet portion of the catalytic converter 10 And a catalyst outlet temperature sensor 32.

  A spark plug 14 is disposed at the central top of the combustion chamber 3. A fuel injection valve 15 that directly injects fuel into the combustion chamber 3 is disposed on the side of the combustion chamber 3 on the intake passage 4 side. The fuel that has been regulated to a predetermined pressure by the high-pressure fuel pump 16 and the pressure regulator 17 is supplied to the fuel injection valve 15 via the high-pressure fuel passage 18. Therefore, when the fuel injection valve 15 of each cylinder is opened by the control pulse, an amount of fuel corresponding to the valve opening period is injected. Reference numeral 19 denotes a fuel pressure sensor that detects the fuel pressure, and 20 denotes a low-pressure fuel pump that sends fuel to the high-pressure fuel pump 16.

  In addition, the internal combustion engine 1 is provided with a water temperature sensor 21 for detecting the engine cooling water temperature and a crank angle sensor 22 for detecting a crank angle. Further, an accelerator opening sensor 23 is provided for detecting the amount of depression of the accelerator pedal by the driver.

  The fuel injection amount, injection timing, ignition timing, etc. of the internal combustion engine 1 are controlled by the control unit 25. The control unit 25 receives detection signals from the various sensors described above. The control unit 25 determines the combustion method, that is, the homogeneous combustion or the stratified combustion, in accordance with the engine operating conditions detected by these input signals, and according to this, the electronic control throttle valve 7 is opened. The fuel injection timing and fuel injection amount of the fuel injection valve 15, the ignition timing of the spark plug 14, and the like are controlled. After the warm-up is completed, in a predetermined region on the low-speed and low-load side, as normal stratified combustion operation, fuel injection is performed at an appropriate time in the compression stroke, and ignition is performed before the compression top dead center. Done. The fuel spray is collected in the vicinity of the spark plug 14, thereby achieving extremely lean stratified combustion with an air-fuel ratio of about 30 to 40. Further, in a predetermined region on the high speed and high load side, as normal homogeneous combustion operation, fuel injection is performed during the intake stroke, and ignition is performed in the vicinity of the MBT point before the compression top dead center. In this case, the fuel becomes a homogeneous mixture in the cylinder. As the homogeneous combustion operation, there are homogeneous stoichiometric combustion in which the air-fuel ratio is the stoichiometric air-fuel ratio and homogeneous lean combustion in which the air-fuel ratio is lean about 20 to 30 depending on the operating conditions.

  The present invention performs super retard combustion so that the exhaust gas temperature becomes high at the time of cold start of the internal combustion engine 1 where early temperature rise of the catalytic converter 10 is required. The fuel injection timing and ignition timing will be described with reference to FIG.

  FIG. 2 shows three examples of super retard combustion. In Example 1, the ignition timing is set to 15 ° to 30 ° ATDC (for example, 20 ° ATDC), and the fuel injection timing (specifically, the fuel injection start timing) is shown. Is set after the compression top dead center and before the ignition timing. At this time, the air-fuel ratio is set to the stoichiometric air-fuel ratio or slightly lean (about 16 to 17).

  That is, in order to promote catalyst warm-up and reduce HC, ignition timing retardation is effective, and ignition after top dead center (ATDC ignition) is desirable, but in order to perform stable combustion with ATDC ignition, It is necessary to shorten the combustion period, and for this purpose, flame propagation due to turbulence must be promoted. As described above, after the compression top dead center, the turbulence generated in the intake stroke and the compression stroke is attenuated, but in the present invention, by the high pressure fuel injection performed during the expansion stroke after the compression top dead center. The gas flow is generated, and thereby the turbulence in the cylinder can be generated and strengthened. Therefore, flame propagation by ATDC ignition is promoted and stable combustion is possible.

  The second embodiment in FIG. 2 is an example in which the fuel injection is divided into two, and the first fuel injection is performed during the intake stroke, and the second fuel injection is performed after the compression top dead center. The ignition timing and the air-fuel ratio (the air-fuel ratio obtained by combining the two injections) are the same as those in the first embodiment.

  As described above, when fuel injection (intake stroke injection) is performed during the intake stroke prior to fuel injection after the compression top dead center (expansion stroke injection), disturbance due to fuel spray in the intake stroke injection is attenuated in the latter half of the compression stroke. However, since the injected fuel is diffused throughout the combustion chamber and contributes to the promotion of HC afterburning by ATDC ignition, the HC reduction and It is effective for raising the exhaust temperature.

  In the third embodiment of FIG. 2, the fuel injection is divided into two, the first fuel injection is performed in the compression stroke, and the second fuel injection is performed after the compression top dead center. As described above, when the fuel injection (compression stroke injection) is performed during the compression stroke prior to the fuel injection after the compression top dead center (expansion stroke injection), the compression stroke injection is compared with the intake stroke injection of the second embodiment. However, since the disturbance of the turbulence due to the fuel spray is delayed, the turbulence due to the first fuel injection remains, and the second fuel injection is performed after the compression top dead center, which is generated by the first fuel injection. The turbulence can be strengthened to promote the turbulence, and the gas flow can be further strengthened near the compression top dead center.

  In the case of Example 3, the first compression stroke injection may be in the first half of the compression stroke, but if it is set in the second half of the compression stroke (after 90 ° BTDC), the disturbance near the top dead center can be further increased. In particular, if the first compression stroke injection is 45 ° BTDC or later, more desirably 20 ° BTDC or later, the gas flow after compression top dead center can be further enhanced.

  As described above, according to the super retarded combustion of the first to third embodiments, the turbulence in the cylinder can be generated and strengthened by the fuel spray immediately before the ignition, and the flame propagation is promoted to perform stable combustion. be able to. In particular, by retarding the ignition timing from 15 ° to 30 ° ATDC, a sufficient afterburning effect for early activation of the catalyst and reduction of HC can be obtained. In other words, even if the ignition timing is greatly delayed in this way, the fuel injection is delayed until just before that, and the generation time of the turbulence is also delayed, so that the combustion improvement by improving the flame propagation can be achieved.

  Here, in the above-described super retard combustion, the exhaust gas temperature can be obtained extremely high. Therefore, if the super retard combustion is performed immediately after the start of the catalytic converter 10 in a completely cold state, the thermal distortion of the catalytic converter 10 is reduced. There are concerns. Therefore, in the present embodiment, the mode is switched while monitoring the temperature state of the catalytic converter 10 by the processing as shown in FIG.

  First, in step 1, the outlet temperature TC of the catalytic converter 10 detected by the catalyst outlet temperature sensor 32 is compared with a predetermined first reference temperature T1, and if it is equal to or lower than the first reference temperature T1, the process proceeds to step 2. Perform normal control when cold. The first reference temperature T1 substantially corresponds to the activation start temperature of the catalyst, and is set to about 150 ° C. to 200 ° C., for example. Also, the normal control when the engine is cold is not for an extreme exhaust temperature increase such as super retard combustion, but for a certain amount of exhaust temperature increase.For example, while performing fuel injection during the intake stroke, compression top dead center Ignition is performed at a time later than the previous MBT point. Alternatively, the compression stroke injection may be performed in addition to the intake stroke injection. When the catalytic converter 10 is in a completely cold state when the engine is started, the temperature of the catalytic converter 10 is gradually increased by the normal control during the cold state.

  If the outlet temperature TC exceeds the first reference temperature T1, it is determined in step 3 whether the catalyst temperature TB detected by the catalyst temperature sensor 31 exceeds the second reference temperature T2. The second reference temperature T2 is a temperature substantially corresponding to the complete activity of the catalyst, and is set to about 250 ° C. to 300 ° C., for example. If the engine is started from the cold state, when the outlet temperature TC reaches the first reference temperature T1, the catalyst temperature TB is normally lower than the second reference temperature T2, and therefore, the process proceeds to step 4 to Perform retarded combustion. As a result, the exhaust gas temperature rises rapidly, and the catalytic converter 10 quickly rises in temperature. This super retard combustion is continued until the catalyst temperature TB exceeds the second reference temperature T2 in Step 3. When the catalyst temperature TB exceeds the second reference temperature T2, the illustrated cold process is terminated, and the normal control after warm-up, that is, the above-described homogeneous combustion operation mode or stratified combustion operation mode after warm-up is executed. The

  As described above, in this embodiment, the super retard combustion is prohibited until the outlet temperature TC reaches the first reference temperature T1, and the catalytic converter reduces the time required until the catalyst is fully activated by the super retard combustion. 10 thermal degradation is avoided.

  FIGS. 4 and 5 show the temperature change of the catalytic converter 10 when the internal combustion engine including the catalytic converter 10 is completely cooled. When the exhaust temperature is very high (FIG. 4), the exhaust gas is relatively exhausted. This shows the case where the temperature is low (FIG. 5). Specifically, as shown in FIG. 6, the temperature TA at the inlet portion (point A) of the catalytic converter 10, the temperature TB1 near the upstream end (point B1) of the monolith catalyst carrier, and the monolith catalyst carrier. 4 shows temperature changes at four locations, a temperature TB2 in the vicinity of the downstream end (point B2) and a temperature TC at the outlet portion (point C) of the catalytic converter 10.

  When a high exhaust temperature is applied as super retard combustion immediately after start-up, as shown in FIG. 4, the catalyst carrier upstream end temperature TB1 rises rapidly with the inlet temperature TA, so the temperature difference ΔT before and after the catalyst carrier Becomes very large. That is, a large thermal distortion occurs.

  On the other hand, when the exhaust temperature is relatively low, as shown in FIG. 5, the temperature difference ΔT before and after the catalyst carrier is sufficiently small. When the outlet temperature TC reaches the predetermined first reference temperature T1, when switching to super retarded combustion, as shown by the broken lines in FIG. The time required to reach a certain catalyst complete activity is not much different from the case of FIG. Note that, at the stage of switching to super retarded combustion, reaction heat begins to be generated inside the catalyst carrier, so that a large temperature difference ΔT does not occur thereafter.

  Note that when starting the super retard combustion as described above, the exhaust gas temperature can be gradually increased by adjusting the fuel injection timing. For example, when the fuel is divided into two injections as in the second embodiment or the third embodiment in FIG. 2, the exhaust gas temperature changes as shown in FIG. 7 depending on the injection timing of the second fuel injection. That is, the exhaust gas temperature increases as the injection timing is retarded. Therefore, if the second fuel injection timing is advanced in advance to the vicinity of the top dead center at the initial stage of transition to super retarded combustion, and then gradually retarded to a predetermined injection timing, the exhaust gas The temperature can be gradually increased, and the thermal distortion of the catalyst carrier can be more reliably suppressed. In this case, the injection timing of the second fuel injection may temporarily be immediately before the compression top dead center, and for example, the injection period can extend over the compression top dead center.

  Next, the flowchart of FIG. 8 shows a different embodiment of mode switching at the time of starting, and this will be described below.

  First, in step 11, the catalyst temperature TB detected by the catalyst temperature sensor 31 is compared with a predetermined third reference temperature T3. If the catalyst temperature TB is equal to or lower than the third reference temperature T3, the process proceeds to step 12, and the above-described cold operation is performed. Perform normal control. The third reference temperature T3 is also substantially equivalent to the activation start temperature of the catalyst, and is set to about 150 ° C. to 200 ° C., for example.

  If the catalyst temperature TB exceeds the third reference temperature T3, the process proceeds to step 13 to determine whether the catalyst temperature TB exceeds the second reference temperature T2 (for example, 250 ° C. to 300 ° C.). If the engine is started from the cold state, the catalyst temperature TB is normally equal to or lower than the second reference temperature T2 when the process proceeds from step 11 to step 13. Therefore, the process proceeds to step 14 to execute the above-described super retard combustion. To do. As a result, the exhaust gas temperature rises rapidly, and the catalytic converter 10 quickly rises in temperature. This super retard combustion is continued until the catalyst temperature TB exceeds the second reference temperature T2 in step 14. When the catalyst temperature TB exceeds the second reference temperature T2, the illustrated cold process is terminated, and the normal control after warm-up, that is, the above-described homogeneous combustion operation mode or stratified combustion operation mode after warm-up is executed. The

  As described above, in this embodiment, the super retard combustion is prohibited until the catalyst temperature TB reaches the third reference temperature T3. As in the above-described embodiment, it is necessary to achieve the complete catalyst activity by the super retard combustion. Thermal degradation of the catalytic converter 10 can be avoided while shortening the time. According to this embodiment, the catalyst outlet temperature sensor 32 can be omitted.

  The super retarded combustion of the present invention can also be used for releasing sulfur poisoning when a NOx trap catalyst is used as the exhaust system catalytic converter 10. The NOx trap catalyst adsorbs NOx when the exhaust air-fuel ratio of the inflowing exhaust gas is lean, and releases the adsorbed NOx when the exhaust air-fuel ratio of the inflowing exhaust gas is rich, and purifies by catalytic action. However, when the sulfur component (SOx) in the fuel is bound to the catalyst, the NOx adsorption performance is lowered. For this reason, it is necessary to perform a process (so-called sulfur poisoning release) for forcibly raising the temperature of the catalyst and releasing SOx at an appropriate time. The super retarded combustion according to the present invention can obtain a very high exhaust temperature, and therefore is suitable for the sulfur poisoning release processing of this NOx trap catalyst.

BRIEF DESCRIPTION OF THE DRAWINGS The structure explanatory drawing which shows the system structure of the whole internal combustion engine which concerns on this invention. The characteristic view which shows the fuel injection timing and ignition timing of the super retard combustion of this invention. The flowchart which shows the mode switching process at the time of a start. The time chart which shows the temperature change of each part of a catalytic converter when exhaust gas temperature is high. The time chart which shows the temperature change of each part of a catalytic converter when exhaust gas temperature is low. Explanatory drawing which shows the temperature measuring point of FIG. 4 and FIG. The characteristic view which shows the relationship between fuel-injection timing and exhaust temperature. The flowchart which shows the Example from which the process of the mode switching at the time of start differs. Explanatory drawing which shows the change of the disturbance in a cylinder in a prior art.

Explanation of symbols

DESCRIPTION OF SYMBOLS 3 ... Combustion chamber 10 ... Catalytic converter 13 ... Exhaust temperature sensor 14 ... Spark plug 15 ... Fuel injection valve 25 ... Control unit 31 ... Catalyst temperature sensor 32 ... Catalyst exit temperature sensor

Claims (9)

  In a direct injection type spark ignition internal combustion engine control device having a fuel injection valve for directly injecting fuel into a cylinder and having an ignition plug, the ignition timing is compression top dead center in a predetermined operating state. It is set later, and super retard combustion is performed to inject fuel before this ignition timing and after compression top dead center. While the catalytic converter provided in the exhaust system is in a predetermined low temperature state, the above super A control apparatus for an in-cylinder direct injection spark ignition internal combustion engine, characterized by prohibiting retarded combustion.   The control apparatus for an in-cylinder direct injection spark-ignition internal combustion engine according to claim 1, wherein the super retard combustion is executed when a temperature increase of the exhaust gas is required as a predetermined operation state.   The in-cylinder direct injection spark ignition internal combustion engine according to claim 2, wherein the temperature of the exhaust gas is required to be raised during a cold start of the internal combustion engine that requires an early temperature increase of the catalytic converter. Control device.   3. The control device for a direct injection spark ignition internal combustion engine according to claim 2, wherein the exhaust gas temperature needs to be raised when performing SOx release processing of the catalytic converter.   The control apparatus for a direct injection spark ignition internal combustion engine according to any one of claims 1 to 4, wherein the super retard combustion is prohibited until the catalytic converter reaches a catalyst activation start.   6. The control apparatus for an in-cylinder direct injection spark ignition internal combustion engine according to claim 1, wherein the super retard combustion is prohibited until the exhaust temperature at the outlet of the catalytic converter reaches a predetermined temperature.   In super retard combustion, prior to fuel injection after compression top dead center, further fuel injection is performed during the intake stroke or compression stroke so that the exhaust gas temperature gradually increases at the start of this super retard combustion. 7. The control apparatus for a direct injection type spark ignition internal combustion engine according to claim 1, wherein the injection timing of the second fuel injection is gradually retarded to a predetermined injection timing.   8. The control device for a direct injection spark ignition internal combustion engine according to claim 1, wherein the ignition timing in the super retard combustion is 15 [deg.] To 30 [deg.] CA after compression top dead center. The control device for a direct injection spark ignition internal combustion engine according to any one of claims 1 to 8, wherein the air-fuel ratio in super retarded combustion is a stoichiometric air-fuel ratio or slightly lean.

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