Control device for internal combustion engine

Abstract

Provided is a control device for an internal combustion engine capable of suppressing dilution of oil due to fuel. A control device controls an internal combustion engine that performs in-cylinder injection. The control device calculates, on the basis of the rotational speed of the internal combustion engine, a large fuel dilution amount region in which the ratio of mixing of oil and liquid fuel injected into the cylinder, adhering to the liner portion and remaining is increased. The large fuel dilution amount region is a part of the combustion cycle of the internal combustion engine. The control device performs control such that fuel is injected in a range other than the large fuel dilution amount range during the combustion cycle.

Description

Technical Field

[0001] This invention relates to a control device for an internal combustion engine. Background Technology

[0002] Patent Document 1 describes a structure in an in-cylinder injection internal combustion engine that directly injects fuel into the cylinder. In order to suppress the dilution of lubricating oil caused by the fuel when using fuel containing alcohol, the internal combustion engine has a structure that more strongly suppresses dilution at low temperatures and when using fuel containing alcohol compared to other times, based on dilution suppression control.

[0003] Patent Document 1: Japanese Patent Application Publication No. 2009-036079 Summary of the Invention

[0004] High-ethanol-concentration fuels are single-component fuels, so if a certain temperature is exceeded, atomization will suddenly begin. However, below that temperature, the fuel injected from the injector (fuel injection valve) is not easily atomized and tends to remain as a liquid. In this state, the liquid fuel adhering to the bushings inside the cylinder of the internal combustion engine is sometimes scraped off by the piston rings and mixes with the oil (lubricating oil). If a large amount of fuel is diluted into the oil, various problems may occur, such as a decrease in oil viscosity or an increase in oil level, and excessive richness caused by fuel atomization from fully warmed-up oil. In the conventional methods described in Patent Document 1, there is room for improvement in suppressing oil dilution caused by fuel.

[0005] The purpose of this invention is to provide a control device for an internal combustion engine that can suppress oil dilution caused by fuel.

[0006] One aspect of the present invention relates to a control device for an internal combustion engine that performs in-cylinder injection. This control device performs the following control: based on the engine speed, it calculates a region of high fuel dilution where the proportion of liquid fuel injected into the cylinder and adhering to the bushing and remaining is increased by mixing with oil; this region of high fuel dilution is part of the combustion cycle of the internal combustion engine; and during the combustion cycle, fuel is injected in a region other than the region of high fuel dilution.

[0007] Invention Effects

[0008] According to the present invention, a control device for an internal combustion engine that can suppress oil dilution caused by fuel can be provided. Attached Figure Description

[0009] Figure 1 This is a block diagram of an internal combustion engine containing a control device involved in the application implementation method.

[0010] Figure 2 This is a diagram illustrating areas with high fuel dilution.

[0011] Figure 3 This is a diagram illustrating an example of the simulation results for the amount of liquid fuel adhering to the bushing.

[0012] Figure 4 It is Figure 3 The graph showing the required time of 2.5 milliseconds converted to CA advance at various engine speeds is shown.

[0013] Figure 5 This is a diagram illustrating an example of a region with large fuel dilution at various speeds.

[0014] Figure 6 This diagram illustrates an example of the steps involved in setting up the sprayable area according to the implementation method. Detailed Implementation

[0015] Hereinafter, the embodiments will be described with reference to the accompanying drawings. To facilitate understanding, the same reference numerals will be used as much as possible to refer to the same components in each drawing, and repeated descriptions will be omitted.

[0016] Figure 1 This is a block diagram of the internal combustion engine 2 of the control device 1 involved in the application embodiment. In this embodiment, the internal combustion engine 2 is an in-cylinder injection internal combustion engine that directly injects fuel into the cylinder (in the combustion chamber 51). Therefore, the internal combustion engine 2 is provided with a combustion chamber 51 (see reference 51) for the cylinder 5. Figure 2 Fuel injection valve 3 directly supplies fuel. Fuel in the fuel tank is delivered into fuel injection valve 3 by a fuel pump.

[0017] Furthermore, in the internal combustion engine 2 of this embodiment, gasoline or alcohol, or a mixture thereof, are used as the aforementioned fuel. Moreover, in the combustion cycle of the internal combustion engine 2, if the mixture consisting of fuel F1 injected into the combustion chamber 51 from the fuel injection valve 3 and air drawn into the combustion chamber through the intake passage is ignited via a spark plug, the mixture burns, causing the piston 6 (reference) to... Figure 2 The crankshaft, which serves as the output shaft of the internal combustion engine 2, reciprocates. Furthermore, the combusted mixture in the combustion chamber 51 is discharged as exhaust gas from each combustion chamber 51 to the exhaust passage.

[0018] The control device 1 according to this embodiment performs various controls related to the internal combustion engine 2. In particular, the control device 1 of this embodiment controls the opening or closing of the fuel injection valve 3, thereby controlling the timing of fuel injection into the combustion chamber 51. The control device 1 is configured, for example, to include a CPU that performs various arithmetic operations related to the above-mentioned control, a ROM that stores programs or data required for its control, a RAM that temporarily stores the CPU's calculation results, and an input / output port for inputting / outputting signals to and from the outside. Furthermore, the control device 1 can also be installed as part of the electronic control unit (ECU) of a vehicle equipped with an internal combustion engine 2.

[0019] A crankshaft angle sensor 4 is installed on the crankshaft of the internal combustion engine 2. The crankshaft angle sensor 4 outputs a signal corresponding to the rotation of the crankshaft to the control device 1. The control device 1 performs the aforementioned control of the fuel injection timing based on the crankshaft angle based on the signal input from the crankshaft angle sensor 4.

[0020] <Overview of areas with high fuel dilution>

[0021] Figure 2 This is a diagram illustrating region A, where fuel dilution is high. Figure 2 The image shows a large area A of fuel dilution when piston 6 is stopped. Figure 2 (A) The figure shows a schematic structure of the interior of cylinder 5 with piston 6 at bottom dead center and a circular diagram corresponding to the crankshaft rotation angle in the structure. Figure 2 (B) The figure shows a schematic structure of the interior of cylinder 5 with piston 6 at top dead center and a circular diagram corresponding to the crankshaft rotation angle in the structure.

[0022] In the following description, Figure 2 (A) Figure 2 (B) The top of the pie chart, i.e., the position of Top Dead Center (BTDC), is represented as 0° before Top Dead Center (BTDC). The bottom of the pie chart, i.e., the position of Bottom Dead Center (BTDC), increases counterclockwise from BTDC and is represented as 180° BTDC. Furthermore, the counterclockwise direction of the pie chart is defined as the advance angle direction, and the clockwise direction as the retreat angle direction. The crankshaft angle shifts clockwise along the pie chart. The right half of the pie chart, from BTDC to Bottom Dead Center, corresponds to the intake phase of the combustion cycle of internal combustion engine 2. The left half of the pie chart, from Bottom Dead Center to BTDC, corresponds to the compression phase of the combustion cycle of internal combustion engine 2.

[0023] Figure 2 (A) shows the piston 6 at bottom dead center, indicating that the combustion chamber 51 in cylinder 5 has reached its maximum volume. If in Figure 2When fuel F1 is injected into the combustion chamber 51 from the fuel injection valve 3 in state (A), the liquefied liquid fuel F2 easily adheres to the bushing 52, which is the cylindrical part of the cylinder 5.

[0024] Consider the scenario where the piston 6 moves to top dead center with liquid fuel F2 adhering to the bushing 52. A portion of the piston ring 61, located on the outer circumferential surface of the piston 6, has a gap in the circumferential direction. Therefore, as... Figure 2 As shown in (B), after piston 6 rises to top dead center, liquid fuel F2 that cannot be completely scraped off by piston ring 61 adheres to and remains in the bushing portion 52, which is located lower than piston 6. Thus, the liquid fuel F2 remaining in bushing portion 52 falls below cylinder 5 and mixes with the oil (lubricating oil) in the engine block. As a result, the oil is diluted by the fuel.

[0025] If a large amount of fuel is diluted into the oil, various problems may occur, such as a decrease in oil viscosity, an increase in oil level, or excessive richness caused by fuel atomization from oil in a fully warmed-up state. In this embodiment, the crankshaft angle where the oil is easily diluted by a large amount of fuel is designated as "large fuel dilution area A". Figure 2 In the example shown where the piston stops, the position of piston 6 at the lower 1 / 4 of BTDC 225°~135° is set as the large fuel dilution area A.

[0026] in, Figure 2 The large fuel dilution area A shown is only the range that can be set when the piston 6 is stopped. When the internal combustion engine 2 is running and the piston 6 is sliding in the cylinder 5, it is necessary to study the rotation state of the internal combustion engine 2 to set the large fuel dilution area A.

[0027] Figure 3 This is a diagram showing an example of the simulation results of the amount of liquid fuel F2 attached to the bushing portion 52. Figure 3 The horizontal axis represents the time (milliseconds) required from the start of fuel F1 injection in the combustion chamber 51 to the time when liquefied liquid fuel F2 adheres to the bushing portion 52. Figure 3 The vertical axis represents the amount of liquid fuel F2 attached to the bushing portion 52 (mg) (hereinafter also referred to as "fuel attachment amount").

[0028] exist Figure 3 In the simulation, the fuel adhesion amount was calculated when the required time (milliseconds) was changed under four conditions: the internal combustion engine 2 speeds of 1200, 1600, 2000, and 3000 rpm. Changing the required time could be exemplified by changing the injection position of the fuel injection valve 3 and the distance between that injection position and the opposing bushing 52. Figure 3In the graph, a solid line graph shows the progression at 3000 rpm, a dashed line graph shows the progression at 2000 rpm, a single-dotted line graph shows the progression at 1600 rpm, and a double-dotted line graph shows the progression at 1200 rpm.

[0029] If reference Figure 3 The simulation results show that the rapid increase in the amount of fuel adhering to the bushing part 52 is independent of the speed of the internal combustion engine 2 or the injection timing of the fuel injection valve 3. The time required from the start of fuel F1 injection in the combustion chamber 51 to the liquefied liquid fuel F2 adhering to the bushing part 52 is 2.5 milliseconds.

[0030] Figure 4 It is Figure 3 The graph shown converts the required time of 2.5 milliseconds to the CA (crankshaft angle) advance at various speeds of internal combustion engine 2. Figure 4 The horizontal axis represents the speed of internal combustion engine 2, and the vertical axis represents the CA advance. For example... Figure 4 As shown, for example, at a speed of 1000 rpm, Figure 3 The required time of 2.5 milliseconds can be converted to a CA advance angle of 15°. Furthermore, for example, at a rotational speed of 3600 rpm, Figure 3 The required time of 2.5 milliseconds can be converted into a CA advance angle of 54°. The rotational speed is proportional to the CA advance.

[0031] If considered Figure 2 The set range of the large area A of fuel dilution under static conditions is shown. Figure 4 The advance amount of CA at each speed shown (i.e., the advance amount of crankshaft angle corresponding to the time required for the amount of fuel adhering to the bushing portion 52 to begin to increase sharply) allows for setting an appropriate large region A of fuel dilution at each speed of the internal combustion engine 2. That is, based on the setting range of the large region A of fuel dilution in a stationary state (BTDC 225°~135°), by adjusting the setting range only according to the CA advance amount offset from the speed, the large region A of fuel dilution corresponding to the speed can be set.

[0032] Figure 5 This is a diagram illustrating an example of a region A with high fuel dilution at various speeds. (See diagram for example.) Figure 5 As shown in (A), at a speed of 1000 rpm, the setting range of the large fuel dilution region A is only offset by the advance angle CA by 15°. That is, at a speed of 1000 rpm, BTDC 240°~150° is set as the large fuel dilution region A. Furthermore, the state where the speed of the internal combustion engine 2 is 1000 rpm can be exemplified by, for example, during startup or during warm-up idling. Figure 5As shown in (B), at a speed of 3600 rpm, the setting range of the large fuel dilution area A is only offset by the advance angle of CA by 54°. That is, at a speed of 3600 rpm, BTDC 279°~189° is set as the large fuel dilution area A.

[0033] That is, by shifting the range of the set large fuel dilution area A by increasing the advance angle CA as the internal combustion engine 2 speed increases, the large fuel dilution area A can be set with high precision at each speed. Moreover, in this embodiment, fuel injection is controlled in the range other than the set large fuel dilution area A during the combustion cycle, thereby avoiding the large fuel dilution area A with high precision regardless of the operating state of the internal combustion engine 2, thus suppressing fuel dilution.

[0034] <Steps for setting up the sprayable area>

[0035] Figure 6 This diagram illustrates an example of the steps involved in setting the sprayable area according to the implementation method. The setting is performed via control device 1. Figure 6 Control of the sprayable area as shown. Figure 6 In the example, the case where the internal combustion engine 2 rotates at 1300 rpm is illustrated and explained.

[0036] In the first stage, a large region A for fuel dilution corresponding to the engine speed is set. For example... Figure 4 As shown, when the internal combustion engine 2 rotates at 1300 rpm, the advance angle CA is 19.5°. Therefore, as Figure 6 As shown in (A), at a speed of 1300 rpm, the setting range of the large fuel dilution area A is from the setting range in the static state (reference). Figure 2 The advance angle of CA is offset by 19.5°. That is, at a speed of 1300 rpm, BTDC 244.5°~154.5° is set as the large fuel dilution area A.

[0037] In stage 2, the first upper limit value E1 is set. For example... Figure 6 As shown in (B), the first upper limit value E1 is the angle by which a specified amount ΔB is advanced along the advance angle direction from the lower limit value (BTDC244.5°) of the large fuel dilution area A set in the first stage.

[0038] In stage 3, a first lower limit value S1 is set. For example... Figure 6 As shown in (C), the first lower limit value S1 is the angle by which the upper limit value (edge ​​of the receding angle direction) of the specified upper stop region C advances only a specified amount ΔD in the receding angle direction.

[0039] Here, as Figure 6As shown in (C), the defined range including the top dead center is set as the top dead center region C. Conventionally, it was considered preferable to set the fuel injection timing within the region of the compression stroke, i.e., BTDC 0° to 90°. However, in recent years, it has been known that even when fuel is injected during the compression stroke, if the injection occurs near the top dead center (e.g., refer to…),… Figure 2 (B) Injecting fuel incorrectly may result in poor fuel-air mixing or piston wall wetting (liquid fuel adhering to the upper surface of piston 6). Therefore, in this embodiment, to avoid these drawbacks, a region of a predetermined width including the top dead center (TDC) is defined as the TDC region C. The fuel injection timing is set to avoid not only the region A with high fuel dilution but also the TDC region C. Furthermore, for the same reasons as the region A with high fuel dilution, the advance angle CA in the TDC region C varies according to the engine speed of the internal combustion engine 2.

[0040] After the implementation of Phase 3, such as Figure 6 As shown in (C), the range from the first lower limit value S1 to the first upper limit value E1 can be set as the first injection region R1. The control device 1 can control the fuel injection of the combustion chamber 51 of the internal combustion engine 2 within the range of the first injection region R1. In the first injection region R1, the first lower limit value S1 is the limit value of the start time of fuel injection (i.e., the opening time of the fuel injection valve 3), and the first upper limit value E1 is the limit value of the end time of fuel injection (i.e., the closing time of the fuel injection valve 3).

[0041] In the fourth stage, it is determined whether the total injection amount of fuel F1 set at the moment is limited to the range of the first injection zone R1 (that is, whether the total injection amount of fuel can be injected within the time before passing through the first injection zone R1).

[0042] In the fourth stage, when the fuel injection quantity is limited to the first injection zone R1, fuel injection control is performed within the first injection zone R1. In this case, the opening and closing times of the fuel injection valve 3 can be any time as long as they are all within the range of the first injection zone R1.

[0043] On the other hand, in stage 4, where the fuel injection quantity is not limited to the first injection zone R1, stage 5 begins, and the second injection zone R2 is set within a range different from the first injection zone R1 in the combustion cycle of the internal combustion engine. For example... Figure 6 As shown in (D), firstly, the time of the predetermined amount ΔB from the large fuel dilution region A during the retraction combustion cycle is set as the second lower limit value S2, and the time of the predetermined amount ΔD from the top dead center region C during the advance combustion cycle is set as the second upper limit value E2. Furthermore, the range from the second lower limit value S2 to the second upper limit value E2 is set as the second injection region R2.

[0044] The control device 1 is capable of controlling the fuel injection in the combustion chamber 51 of the internal combustion engine 2 within the range of the second injection zone R2. In the second injection zone R2, the second lower limit value S2 is the limit value of the start time of fuel injection (i.e., the opening time of the fuel injection valve 3), and the second upper limit value E2 is the limit value of the end time of fuel injection (i.e., the closing time of the fuel injection valve 3).

[0045] like Figure 6 As shown in (D), the first injection region R1 and the second injection region R2 are positioned on opposite sides of the combustion cycle, separated by the fuel dilution region A and the top dead center region C. The first injection region R1 is mainly included in the intake phase of the combustion cycle of the internal combustion engine 2. The second injection region R2 is mainly included in the compression phase of the combustion cycle of the internal combustion engine 2. Furthermore, depending on the rotational speed of the internal combustion engine 2, for example... Figure 5 As shown in (B), sometimes the entire range of the large fuel dilution region A is included in the intake process. In this case, a portion of the second injection region R2 (e.g., including a portion of the second lower limit value S2) may be included in the intake process.

[0046] After implementing the fifth stage, the control device 1 controls the amount of fuel remaining in the first injection zone within the second injection zone R2. In this case, the opening and closing times of the fuel injection valve 3 can be any time as long as they are both within the range of the second injection zone R2. That is, when entering the fifth stage, the control device 1 can control fuel injection within both the first injection zone R1 and the second injection zone R2.

[0047] Alternatively, you can set... Figure 6 (B) and (C) show the steps and settings for the first spray zone R1. Figure 6 (D) The step of the second injection zone R2 shown is replaced. In this case, if the total injection amount is not limited to the second injection zone R2, fuel injection is also performed in the first injection zone R1. Furthermore, both the first injection zone R1 and the second injection zone R2 can be set before determining whether the fuel injection amount is limited to the first injection zone R1 or the second injection zone R2.

[0048] Furthermore, after setting both the first injection zone R1 and the second injection zone R2, the injection time corresponding to the total injection amount can be set at any time within the range of the first injection zone R1 and the second injection zone R2. For example, multiple fuel injections can be performed within the range of either the first injection zone R1 or the second injection zone R2.

[0049] The effects of this implementation method will be explained.

[0050] The control device 1 described in this embodiment is used to control an internal combustion engine 2 that performs in-cylinder injection. Based on the rotational speed of the internal combustion engine 2, the control device 1 calculates a large fuel dilution region A, where the proportion of liquid fuel F2 injected into the cylinder 5 and adhering to the bushing portion 52 and remaining mixed with oil increases. The large fuel dilution region A is part of the combustion cycle of the internal combustion engine 2. The control device 1 performs control as follows: during the combustion cycle, fuel is injected in a range other than the large fuel dilution region A.

[0051] This structure allows for control of fuel injection timing to avoid the region A with high fuel dilution, thus reducing the amount of liquid fuel F2 adhering to the bushing portion 52. As a result, fuel-induced oil (lubricating oil) dilution in the internal combustion engine 2 can be suppressed.

[0052] Furthermore, the control device 1 involved in this embodiment sets the common required time until the fuel F1 injected into the cylinder adheres to the bushing portion 52, converts the required time into the advance of the crankshaft angle according to the rotational speed, and calculates the large area A of fuel dilution based on the converted advance.

[0053] The amount of fuel adhering to the bushing portion 52 is primarily independent of the rotational speed of the internal combustion engine 2, but can be expressed as the useless time from fuel injection to fuel adhering to the bushing portion 52 plus a time constant (the time required after injection). In this embodiment, based on Figure 3 The simulation results shown indicate that the required time is set to 2.5 milliseconds. Furthermore, according to... Figure 3 The simulation results show that the required time is a constant value independent of the rotational speed of the internal combustion engine 2. Therefore, in this embodiment, a common "required time" independent of the operating state of the internal combustion engine 2 is set, and the large region A of fuel dilution corresponding to the rotational speed is calculated based on this required time. This allows the large region A of fuel dilution to be set within a more appropriate range, independent of the operating state of the internal combustion engine 2, such as its rotational speed. Consequently, the amount of liquid fuel F2 adhering to the bushing portion 52 can be further reduced, thus further suppressing fuel dilution in the internal combustion engine 2.

[0054] Furthermore, in the control device 1 of this embodiment, the aforementioned "common required time" is the time that is independent of the rotational speed of the internal combustion engine 2 and tends to increase as the required time increases.

[0055] With this structure, if the required time is used as a reference, the large fuel dilution area A can be set within a more appropriate range more reliably without depending on the operating state of the internal combustion engine 2, such as the speed. Therefore, the fuel dilution of oil in the internal combustion engine 2 can be suppressed more reliably.

[0056] Furthermore, the control device 1 of this embodiment sets the moment when the combustion cycle of the internal combustion engine 2 with only an advance angle in the large fuel dilution region A is a predetermined amount ΔB as a first upper limit value E1, and sets the moment when the combustion cycle with only an advance angle in the top dead center region C, which includes the predetermined width of the combustion cycle, is a predetermined amount ΔD as a predetermined amount in the retreat angle combustion cycle, as a first lower limit value S1. The range from the first lower limit value S1 to the first upper limit value E1 is defined as the first injection region R1. Furthermore, the moment when the combustion cycle with only an advance angle in the large fuel dilution region A is a predetermined amount ΔB is set as a second lower limit value S2, and the moment when the combustion cycle with only an advance angle in the top dead center region C is a predetermined amount ΔD as a predetermined upper limit value E2. The range from the second lower limit value S2 to the second upper limit value E2 is defined as the second injection region R2. The control device 1 controls fuel injection within the ranges of the first injection region R1 and the second injection region R2.

[0057] This structure allows for more reliable avoidance of the set fuel injection timing from the region of high fuel dilution (A) or the top dead center (C). Therefore, it can more reliably suppress fuel dilution in the internal combustion engine 2 caused by fuel, and also avoid potential malfunctions such as mixture deterioration or piston wall wetting when fuel is injected near top dead center.

[0058] Furthermore, the control device 1 according to this embodiment controls the fuel injection in the first injection region R1 when the fuel injection amount is limited to the first injection region R1, injects fuel in the first injection region R1 when the fuel injection amount is not limited to the first injection region R1, and further injects the remaining fuel of the fuel injection amount in the second injection region R2.

[0059] This structure allows the fuel injection timing to be set within the range of the first injection zone R1 or the second injection zone R2 regardless of the amount of fuel injected, thus more reliably suppressing fuel dilution in the internal combustion engine 2.

[0060] Furthermore, the control device 1 according to this embodiment can also be configured to perform a second fuel injection during the intake phase of the combustion cycle when the total fuel injection quantity is greater than or equal to the fixed injection quantity in the compression phase of the combustion cycle. With this structure, similar to the embodiment described above, it is possible to suppress oil dilution caused by fuel in the internal combustion engine 2.

[0061] The embodiments described above have been illustrated with reference to specific examples. However, the present invention is not limited to these specific examples. Those skilled in the art can make appropriate design modifications to these specific examples, and as long as they possess the features of the present invention, they are also included within the scope of the present invention. The elements, their configurations, conditions, shapes, etc., of the aforementioned specific examples are not limited to the illustrated elements and can be appropriately modified. As long as no technical contradiction arises, the elements of the aforementioned specific examples can be appropriately combined and changed.

[0062] Symbol Explanation

[0063] 1-Control device, 2-Internal combustion engine, 5-Cylinder, 52-Bushing section, A-Large area for fuel dilution, C-Top dead center area, F1-Fuel, F2-Liquid fuel, R1-First injection zone, S1-First lower limit, E1-First upper limit, R2-Second injection zone, S2-Second lower limit, E2-Second upper limit.

Claims

1. A control device for an internal combustion engine, characterized in that, The control device performs the following control: Based on the engine speed, calculate the area of ​​increased fuel dilution due to the increased proportion of liquid fuel mixed with oil that is injected into the cylinder and adheres to the bushing. The area with the largest fuel dilution is part of the combustion cycle of the internal combustion engine; In the combustion cycle, fuel is injected in a range other than the area of ​​high fuel dilution.

2. The control device for an internal combustion engine according to claim 1, characterized in that, The common time required for the injected fuel to adhere to the bushing is set, and this time is converted into a crankshaft angle advance based on the rotational speed. The large area of ​​fuel dilution is calculated based on the converted advance.

3. The control device for an internal combustion engine according to claim 2, characterized in that, The common required time is independent of the rotational speed and tends to increase as the required time increases.

4. The control device for an internal combustion engine according to claim 1, characterized in that, The control device performs the following control: The first upper limit value is set as the moment when the combustion cycle is advanced by a predetermined amount from the large fuel dilution area, and the first lower limit value is set as the moment when the combustion cycle is retreated by a predetermined amount from the top dead center area including the top dead center of the combustion cycle. The first injection area is set as the range from the first lower limit value to the first upper limit value. The second lower limit is defined as the moment when the combustion cycle is only deflected by a predetermined amount from the large fuel dilution region, the second upper limit is defined as the moment when the combustion cycle is only advanced by a predetermined amount from the top dead center region, and the second injection region is defined as the range from the second lower limit to the second upper limit. and Fuel is injected within the range of the first injection zone and the second injection zone.

5. The control device for an internal combustion engine according to claim 4, characterized in that, The control device performs the following control: When the fuel injection quantity is limited to the first injection region, fuel is injected in the first injection region; and If the fuel injection amount is not limited to the first injection area, the fuel injection is controlled in the first injection area, and the remaining fuel of the fuel injection amount is further injected in the second injection area.

6. The control device for an internal combustion engine according to claim 1, characterized in that, When the total amount of fuel injected is greater than or equal to the fixed amount injected during the compression phase of the combustion cycle, a second fuel injection is performed during the intake phase of the combustion cycle.

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