WO2021090653A1

WO2021090653A1 - Internal combustion engine control device and control method

Info

Publication number: WO2021090653A1
Application number: PCT/JP2020/038783
Authority: WO
Inventors: 高輔神田; 村井　淳; 吉辰中村
Original assignee: 日立Astemo株式会社
Priority date: 2019-11-08
Filing date: 2020-10-14
Publication date: 2021-05-14
Also published as: JPWO2021090653A1; JP7232349B2; BR112022004206A2

Abstract

In the present invention, a valve overlap (O/L) period of an intake valve and an exhaust valve of an internal combustion engine is set so as to include a period on or after an exhaust top dead center point, and an injection end timing of a fuel injection valve through which fuel is injected to the inside of an intake port that is opened/closed by means of the intake valve is set such that fuel having been injected by means of the fuel injection valve at the injection end timing is caused to flow into a combustion chamber during the valve O/L period on or after the exhaust top dead center point.

Description

Internal combustion engine control device and control method

The present invention relates to a control device and a control method for an internal combustion engine that injects fuel in synchronization with intake air from a port injection type fuel injection valve.

In recent fuel-efficient internal combustion engines, the S / V ratio (ratio of the surface area of the combustion chamber to the volume of the combustion chamber) is reduced by reducing the bore diameter to reduce cooling loss, and the straightening of the intake port is used to reduce the in-cylinder flow. Attempts have been made to improve fuel efficiency by strengthening and improving combustion.

In such a fuel-efficient internal combustion engine, when fuel is injected from a port injection type fuel injection valve in synchronization with intake air, the distance from the injection hole to the inner wall surface of the cylinder is shortened, or the fuel flows toward the inner wall surface of the cylinder. Due to the increase in intake air, fuel collision with the inner wall surface of the cylinder increases and the amount of fuel adhered increases. On the other hand, as described in Patent Document 1, for example, it is known that high-temperature exhaust gas flows back into the cylinder from the exhaust port to vaporize the fuel adhering to the inner wall surface of the cylinder.

Japanese Unexamined Patent Publication No. 2005-248766

However, Patent Document 1 does not disclose the injection end timing when fuel is injected in synchronization with the intake air from the port injection type fuel injection valve. Therefore, if fuel injection is performed even after the exhaust valve is closed, the amount of fuel adhering to the inner wall surface of the cylinder increases because there is no backflow of exhaust gas from the exhaust port into the cylinder, and PN (during exhaust). The number of fine particles) may increase.

Therefore, an object of the present invention is to provide a control device and a control method for an internal combustion engine that further suppresses fuel adhesion to the inner wall surface of the cylinder due to synchronous intake intake injection.

Therefore, in the internal combustion engine control device according to the present invention, the valve overlap period of the intake valve and the exhaust valve of the internal combustion engine is set after the exhaust top dead point, and fuel is supplied to the inside of the intake port opened and closed by the intake valve. The injection end timing of the fuel injection valve to be injected is set so that the fuel injected from the fuel injection valve at the injection end timing flows into the combustion chamber during the valve overlap period.

Further, in the control method of the internal combustion engine according to the present invention, the valve overlap period of the intake valve and the exhaust valve of the internal combustion engine is set after the exhaust top dead point, and fuel is injected into the intake port opened and closed by the intake valve. The injection end timing of the fuel injection valve is set so that the fuel injected from the fuel injection valve at the injection end timing flows into the combustion chamber during the valve overlap period.

According to the control device and control method for the internal combustion engine according to the present invention, it is possible to suppress fuel adhesion to the inner wall surface of the cylinder due to intake synchronous injection.

It is a block diagram which shows an example of the internal combustion engine by 1st Embodiment. It is a schematic diagram which shows the image of suppressing fuel adhesion in a cylinder by the same embodiment. It is explanatory drawing which shows an example of the valve timing in the cold state by the same embodiment. It is explanatory drawing which shows an example of the injection start and injection end timing by the same embodiment. It is a flowchart which shows an example of the control process of the fuel injection valve by the same embodiment. It is explanatory drawing which shows an example of the injection start and injection end timing by the 2nd Embodiment. It is explanatory drawing which shows the injection start timing setting method by the same embodiment. It is explanatory drawing which shows the 1st method of optimizing the injection end timing by the same embodiment. It is explanatory drawing which shows the 2nd method of optimizing the injection end timing by the same embodiment. It is explanatory drawing which shows the 3rd method of the injection end timing optimization by the same embodiment. It is a time chart which shows the influence of the engine rotation speed change by 3rd Embodiment. It is explanatory drawing which shows the injection end timing setting method by the same embodiment. It is a flowchart which shows an example of the control process of the fuel injection valve by the same embodiment. It is a time chart which shows the injection end timing setting method by 4th Embodiment. It is a schematic diagram which shows the fuel adhesion image in a cylinder by the conventional intake air synchronous injection.

[First Embodiment]
The first embodiment for carrying out the present invention will be described in detail with reference to FIGS. 1 to 5.

FIG. 1 shows an example of an internal combustion engine to which the control device and the control method according to the present invention are applied. The internal combustion engine 1 is a vehicle internal combustion engine that is mounted on a vehicle to generate power for the vehicle, and is, for example, a multi-cylinder 4-stroke spark ignition engine.

The internal combustion engine 1 has a cylinder block 2 in which a cylinder 2A and a crank chamber 2B are formed, and a cylinder head 3 in which an intake port 3A and an exhaust port 3B are formed. The cylinder head 3 is attached to the cylinder block 2 so that the opening 3Aop of the intake port 3A and the opening 3Bop of the exhaust port 3B face the cylinder 2A.

A piston 4 is reciprocally inserted into the cylinder 2A of the cylinder block 2 in the axial direction of the cylinder 2A, and a combustion chamber 5 is formed between the crown surface 4a of the piston 4 and the lower surface of the cylinder head 3. There is. A water jacket 2C for circulating cooling water circulating between the internal combustion engine 1 and an external heat exchanger is formed in the wall around the cylinder 2A.

A crank shaft 6 is arranged in the crank chamber 2B of the cylinder block 2, and the crank shaft 6 is connected to the piston 4 via a conrod (connecting rod) 7 whose upper end is rotatably attached to the piston 4 by a piston pin 4b. It is connected.

The crankshaft 6 is rotatably supported by the main bearing (not shown) of the cylinder block 2 by the journal 6a. Further, the crankshaft 6 has a crankpin 6b eccentric from the rotation axis of the journal 6a, and the crankpin 6b is rotatably connected to the lower end of the connecting rod 7. The journal 6a and the crank pin 6b are connected by a crank arm 6c.

The cylinder head 3 is provided with an intake valve 8 and an exhaust valve 9. The intake valve 8 includes an umbrella portion 8a that abuts on the opening 3Aop of the intake port 3A facing the combustion chamber 5, a rod-shaped stem portion 8b extending from the umbrella portion 8a, and a tappet portion located at the extending end of the stem portion 8b. Has 8c. Similarly, the exhaust valve 9 is located at the umbrella portion 9a that comes into contact with the opening 3Bop of the exhaust port 3B facing the combustion chamber 5, the rod-shaped stem portion 9b that extends from the umbrella portion 9a, and the extending end of the stem portion 9b. It has a tappet portion 9c to be used.

When the intake cam 11 that rotates integrally with the intake cam shaft 10 rotatably supported by the cylinder head 3 comes into contact with the tappet portion 8c, the intake valve 8 reciprocates in the axial direction of the stem portion 8b. As a result, the umbrella portion 8a of the intake valve 8 periodically opens and closes the opening 3Aop of the intake port 3A facing the combustion chamber 5. Similarly, when the exhaust cam 13 that rotates integrally with the exhaust cam shaft 12 rotatably supported by the cylinder head 3 comes into contact with the tappet portion 9c, the exhaust valve 9 reciprocates in the axial direction of the stem portion 9b. As a result, the umbrella portion 9a of the exhaust valve 9 opens and closes the opening 3Bop of the exhaust port 3B facing the combustion chamber 5. The rotation of the crankshaft 6 is transmitted to the intake camshaft 10 and the exhaust camshaft 12 via a timing belt (not shown).

An intake pipe 14 for guiding air from the outside of the vehicle to the internal combustion engine 1 is connected to the intake port 3A of the cylinder head 3 via an intake manifold (not shown). An electronically controlled throttle 15 including a throttle motor 15a and a throttle valve 15b is arranged in the intake pipe 14. The electronically controlled throttle 15 adjusts the amount of intake air sucked into the combustion chamber 5 of each cylinder 2A via the intake valve 8.

An exhaust pipe 16 for guiding the exhaust generated by the internal combustion engine 1 to the outside of the vehicle is connected to the exhaust port 3B of the cylinder head 3 via an exhaust manifold (not shown). A front catalytic converter 17 and a rear catalytic converter 18 that convert exhaust components are arranged in the exhaust pipe 16.

The cylinder head 3 is provided with a port injection type fuel injection valve 19 that injects fuel into the intake port 3A on the upstream side of the intake valve 8. The fuel injection valve 19 is, for example, a swirl spray type fuel injection valve that is atomized by swirling fuel in a swirl chamber formed in a fuel passage and injecting the fuel in a spiral shape. The fuel injected from the fuel injection valve 19 into the intake port 3A during the valve closing period of the intake valve 8 adheres to the umbrella portion 8a of the intake valve 8 which has become hot due to the heat of combustion and vaporizes, and the intake valve 8 is opened. Mix with intake air during the valve period to form a uniform air-fuel mixture. On the other hand, the fuel injected from the fuel injection valve 19 into the intake port 3A during the valve opening period of the intake valve 8 passes between the umbrella portion 8a of the intake valve 8 and the opening 3Aop of the intake port 3A and enters the combustion chamber 5. Inflow with intake air.

A spark plug 20 for igniting and burning a mixture of fuel and air in the combustion chamber 5 is attached to the cylinder head 3 at a position facing the combustion chamber 5.

The variable valve timing mechanism 21 is composed of an intake variable mechanism 21a and an exhaust variable mechanism 21b. The intake variable mechanism 21a is a mechanism that continuously changes the valve timing of the intake valve 8 in the advance direction and the retard direction by continuously changing the rotation phase of the intake camshaft 10 with respect to the crankshaft 6 by an actuator. is there. The variable exhaust mechanism 21b is a mechanism that continuously changes the valve timing of the exhaust valve 9 in the advance and retard directions by continuously changing the rotation phase of the exhaust camshaft 12 with respect to the crankshaft 6 by an actuator. is there.

An engine control module (hereinafter referred to as "ECM") 100 is provided as a first control unit for controlling the throttle motor 15a of the electronically controlled throttle 15, the fuel injection valve 19, and the spark plug 20. Further, the VTC controller 200 is provided as a second control unit that individually controls the two actuators of the intake variable mechanism 21a and the exhaust variable mechanism 21b. The ECM 100 and the VTC controller 200 have a microcomputer including a processor such as a CPU (Central Processing Unit), a non-volatile memory such as a ROM (Read Only Memory), a volatile memory such as a RAM (Random Access Memory), and an input / output port. .. The ECM 100 and the VTC controller 200 are communicably connected to each other by a communication line such as a CAN (Control Area Network) to form a control device for the internal combustion engine 1.

The ECM100 inputs the output signals of various sensors via the input / output ports of the built-in microprocessor. Examples of various sensors include an accelerator opening sensor 22, an intake air pressure sensor 23, a crank angle sensor 24, a throttle sensor 25, an intake cam sensor 26, an exhaust cam sensor 27, and a water temperature sensor 28. The accelerator opening sensor 22 is a sensor for detecting the amount of depression of the accelerator pedal 29, that is, the accelerator opening ACC. The intake air pressure sensor 23 is a sensor for detecting the intake air pressure PS of the internal combustion engine 1. The crank angle sensor 24 is a sensor that outputs a pulsed crank angle signal CRANK whose frequency changes according to the rotation speed of the crankshaft 6. The throttle sensor 25 is a sensor for detecting the opening degree TVO of the throttle valve 15b. The intake cam sensor 26 is a sensor that outputs a pulsed intake cam signal CAM1 whose frequency changes according to the rotation speed of the intake cam shaft 10. The exhaust cam sensor 27 is a sensor that outputs a pulsed exhaust cam signal CAM2 whose frequency changes according to the rotation speed of the exhaust cam shaft 12. The water temperature sensor 28 is a sensor for detecting the water temperature TW of the cooling water circulating between the internal combustion engine 1 and the external heat exchanger, such as the cooling water flowing through the water jacket 2C.

In the ECM100, the processor of the built-in microcomputer reads the program stored in advance in the non-volatile memory into the volatile memory and executes it. As a result, the ECM 100 determines the operating state of the internal combustion engine 1 from the output signals of the various sensors described above, and operates the electronically controlled throttle 15, the fuel injection valve 19, and the spark plug 20 according to the operating state of the internal combustion engine 1. Generate a signal. Further, the ECM 100 calculates a target value of the rotation phase adjusted by the variable valve timing mechanism 21. Then, the ECM 100 outputs the generated operation signal to the electronically controlled throttle 15, the fuel injection valve 19, and the ignition plug 20, and outputs the target value of the rotation phase adjusted by the variable valve timing mechanism 21 to the VTC controller 200. ..

Specifically, the ECM 100 calculates the fuel injection amount FI according to the operating state of the internal combustion engine 1, and injects the fuel pressure (fuel pressure) supplied to the fuel injection valve 19, the injection hole diameter of the fuel injection valve 19, and the like. Based on the characteristics, the fuel injection time required to inject the fuel injection amount FI is calculated. The fuel injection time is converted into a fuel injection period indicated by the amount of rotation angle of the crankshaft 6 based on the engine rotation speed NE calculated by using the crank angle signal CRANK in the ECM100. The fuel injection period is a continuous period in which fuel is injected from the fuel injection valve 19 in one cycle (4 strokes) in the cold state of the internal combustion engine 1. Further, the ECM 100 includes an injection timing setting means for setting an injection start timing and an injection end timing during the fuel injection period. Then, the ECM 100 outputs an injection signal including a fuel injection period, an injection start timing, and an injection end timing as an operation signal of the fuel injection valve 19. In this specification, the term "period" means the amount of rotation angle of the crankshaft 6.

The fuel injection amount FI is calculated as follows, for example. That is, the ECM 100 calculates the fuel injection amount FI by multiplying the basic injection amount by various correction coefficients in consideration of the water temperature TW and the like, and adding the correction value for compensating for the injection delay of the fuel injection valve 19 to this multiplication value. The basic injection amount can be calculated based on the engine rotation speed NE calculated using the crank angle signal CRANK and the intake air amount Q estimated from the output signal related to the intake air pressure PS of the intake air pressure sensor 23. An airflow sensor may be provided in the intake pipe 14 to directly detect the intake air amount Q from the output signal of the airflow sensor.

Further, the ECM 100 calculates the target value of the rotation phase adjusted by the variable valve timing mechanism 21 based on the engine operation conditions such as the engine rotation speed NE and the engine load TP calculated by using the crank angle signal CRANK. The ECM 100 can use the fuel injection amount FI, the intake air pressure PS, the throttle opening TVO, and the like as the engine load TP.

The VTC controller 200 inputs the crank angle signal CRANK, the intake cam signal CAM1 and the exhaust cam signal CAM2 via the ECM100, and based on these signals, determines the rotation phases of the intake camshaft 10 and the exhaust camshaft 12 with respect to the crankshaft 6. measure. Then, the VTC controller 200 generates and outputs an operation signal of at least one actuator of the intake variable mechanism 21a and the exhaust variable mechanism 21b so that the measured value of the rotational phase approaches the target value, thereby controlling the feedback of the rotational phase. To carry out.

It is assumed that the temperature of the internal combustion engine 1 has not risen sufficiently in the cold state immediately after the start of the internal combustion engine 1. Therefore, when fuel is injected into the intake port 3A from the fuel injection valve 19 with the intake valve 8 closed, not only is the injected fuel difficult to vaporize, but the injected fuel easily adheres to the wall surface of the intake port 3A. Become. Therefore, in the cold state of the internal combustion engine 1, the ECM 100 performs intake synchronous injection in which fuel is injected in synchronization with intake in a state where the intake valve 8 is opened, so that the injected fuel flows into the combustion chamber 5 together with the intake air. I have to.

By the way, in the internal combustion engine 1, in order to improve fuel efficiency, the diameter of the cylinder bore is reduced in order to reduce the S / V ratio and the cooling loss, and the intake port is used to strengthen the in-cylinder flow to improve combustion. It is assumed that 3A is straightened.

When the internal combustion engine 1 is configured to improve fuel efficiency as described above, the following problems occur when intake synchronous injection is performed as shown in FIG. That is, the distance from the injection hole of the fuel injection valve 19 to the inner wall surface of the cylinder 2A close to the exhaust port 3B is shortened, or the intake air flowing toward the inner wall surface of the cylinder 2A is increased, so that the inner wall surface of the cylinder 2A is reached. Fuel collisions increase and the amount of fuel deposited tends to increase. This increases the amount of unburned fuel, which may not only reduce fuel consumption but also increase PN in the cold state of the internal combustion engine 1.

Therefore, as shown in FIG. 2, when the intake synchronous injection is performed in the cold state of the internal combustion engine 1, in addition to opening the intake valve 8, the exhaust valve 9 is opened as follows. That is, the exhaust valve 9 is opened so that the high-temperature exhaust gas flows back from the exhaust port 3B to the combustion chamber 5 due to the decrease in the internal pressure of the combustion chamber 5 accompanying the lowering of the piston 4. As a result, the fuel collision with the inner wall surface of the cylinder 2A during the intake synchronous injection is reduced by the so-called high temperature air curtain due to the backflow exhaust from the exhaust port 3B, and the fuel adhesion to the inner wall surface of the cylinder 2A is suppressed. I have to.

FIG. 3 shows the valve timings of the intake valve 8 and the exhaust valve 9 in the cold state of the internal combustion engine 1. The valve timing is the rotation angle of the crankshaft 6 when the intake valve 8 and the exhaust valve 9 open and close. In FIG. 3, with the exhaust top dead point TDC as 0 deg, the angle when rotating clockwise around the origin O indicates the rotation angle of the crankshaft 6, and the intake cam when the crankshaft 6 rotates two turns (720 deg). The shaft 10 and the exhaust cam shaft 12 each rotate once (360 deg).

At the first rotation (0 to 360 deg) of the crankshaft 6, the intake valve 8 opens at the valve opening timing IVO between the exhaust top dead center TDC and the intake bottom dead center BDC, and then the exhaust valve 9 closes. The valve is set to close at the valve timing EVC. The intake valve 8 closes at the valve closing timing IVC which is retarded (or late) by a predetermined working angle of the intake cam 11 with respect to the valve opening timing IVO. Then, at the second rotation (360 to 720 deg) of the crankshaft 6, the exhaust valve 9 advances by a predetermined working angle of the exhaust cam 13 with respect to the valve closing timing EVC at the third rotation (720 to 1080 deg) (). Or early) Valve opening timing EVO opens the valve. As described above, in the cold state of the internal combustion engine 1, the valve overlap (O / L) period in which both the intake valve 8 and the exhaust valve 9 are opened is between the exhaust top dead center TDC and the intake bottom dead center BDC. It is provided, but the reason is as follows.

In the intake synchronous injection performed in the cold state of the internal combustion engine 1, when the valve O / L period starts in the range advanced from the exhaust top dead center TDC, the pressure of the combustion chamber 5 rises with the rise of the piston 4 and the intake port 3A There is a risk that the injected fuel will blow through to the exhaust port 3B. Therefore, the valve opening timing IVO of the intake valve 8 is set after the exhaust top dead center TDC. Further, in the intake synchronous injection, in order to reduce the fuel collision with the inner wall surface of the cylinder 2A by the so-called high temperature air curtain due to the backflow exhaust, the pressure of the combustion chamber 5 decreases as the piston 4 descends, and the combustion chamber 5 from the exhaust port 3B. It is done so that the exhaust flows back to. Therefore, the valve closing timing EVC of the exhaust valve 9 is set to a range that is retarded from the valve opening timing IVO of the intake valve 8 and is before the intake bottom dead center BDC. Therefore, in the cold state of the internal combustion engine 1, the valve O / L period in which both the intake valve 8 and the exhaust valve 9 are opened is provided between the exhaust top dead center TDC and the intake bottom dead center BDC.

FIG. 4 shows an example of setting the fuel injection period regarding the injection start timing FO and the injection end timing FC. At the top of FIG. 4, two valve opening periods of the intake valve 8 and the exhaust valve 9 are shown corresponding to the rotation angle of the crankshaft 6 before and after the exhaust top dead center TDC. Further, in the lower part of FIG. 4, the exhaust flow velocity at the exhaust port 3B is shown corresponding to the rotation angle of the crankshaft 6 before and after the exhaust top dead center TDC. Here, the exhaust flow velocity of the forward exhaust gas flowing from the combustion chamber 5 to the exhaust port 3B is indicated by a positive value, and the exhaust flow velocity of the backflow exhaust gas flowing from the exhaust port 3B to the combustion chamber 5 is indicated by a negative value. ..

A known time lag (required time) occurs before the fuel injected from the fuel injection valve 19 reaches the opening 3Aop of the intake port 3A opened and closed by the intake valve 8, that is, the intake inlet of the combustion chamber 5. .. Therefore, the period during which the fuel injected from the fuel injection valve 19 reaches the opening 3Aop of the intake port 3A opened and closed by the intake valve 8, that is, the intake inlet of the combustion chamber 5 (fuel arrival period) is as a whole. It is retarded by the amount of angle corresponding to the required arrival time with respect to the fuel injection period. The period of the fuel arrival period that overlaps with the valve O / L period is the inflow period (intake synchronous injection period) in which the fuel injected from the fuel injection valve 19 flows into the combustion chamber 5.

In the intake synchronous injection performed in the cold state of the internal combustion engine 1, as described above, the fuel collision with the inner wall surface of the cylinder 2A is reduced by the so-called high temperature air curtain due to the backflow exhaust from the exhaust port 3B. Therefore, it is necessary to end the inflow period within the valve O / L period in which the backflow of exhaust gas can occur. Therefore, the injection end timing FC, which is the end of the fuel injection period, is set so that the fuel injected from the fuel injection valve 19 at the injection end timing FC flows into the combustion chamber 5 during the valve O / L period. Specifically, on the premise that the required arrival time has been acquired in advance by an experiment or simulation, the injection end timing FC sets the required arrival time with respect to the end of the inflow period ending within the valve O / L period. It is set as an angle advanced by the amount of angle corresponding to. For example, the injection end timing FC is set so that the end of the valve O / L period and the end of the inflow period coincide with each other, so that the overlap period between the valve O / L period and the inflow period can be lengthened. Further, for example, the injection end timing FC is set so that the fuel arrival period falls within the valve O / L period when the fuel injection period is shorter than the valve O / L period.

In some cases, for example, the engine rotation speed NE is in the low speed range, the time required to reach the engine is extremely small compared to the fuel injection period and the valve O / L period and can be ignored. In this case, the injection end timing FC may simply be set as the end of the inflow period that ends within the valve O / L period.

The injection start timing FO, which is the beginning of the fuel injection period, is set to an angle advanced by the angle amount of the fuel injection period from the injection end timing FC set as described above. Therefore, the injection start timing FO may be either coincident with the valve opening timing IVO of the intake valve 8 or may be advanced or retarded from the valve opening timing IVO.

As described above, the injection start timing FO and the injection end timing FC can be set on the assumption that backflow exhaust can occur during the entire period of the valve O / L period. On the other hand, when the data on the backflow period in which the exhaust actually flows backward is acquired in advance by experiments or simulations, the injection start timing FO and the injection end timing FC are set according to the backflow period as follows. be able to.

As shown in the lower part of FIG. 4, during the valve opening period of the exhaust valve 9 before the exhaust top dead center TDC, almost forward exhaust flows into the exhaust port 3B due to the pressure rise in the combustion chamber 5. On the other hand, in the valve O / L period after the exhaust top dead center TDC, the exhaust gas flows back from the exhaust port 3B to the combustion chamber 5 due to the pressure drop in the combustion chamber 5. However, during the valve O / L period, the opening degree of the exhaust valve 9 gradually decreases and the opening degree of the intake valve 8 gradually increases. Therefore, in reality, backflow occurs continuously in a part of the valve O / L period at the beginning of the start (hatched part in the figure), and almost all exhaust backflow occurs in the subsequent valve O / L period. It may not be. For example, the backflow period occurs in the range from the exhaust top dead center TDC to the rotation angle 30 to 60 deg retarded from this.

When the data on the backflow period shown in the lower part of FIG. 4 is acquired in advance, the injection end timing FC is set in consideration of the effect of suppressing fuel adhesion to the inner wall surface of the cylinder 2A due to the backflow exhaust during the backflow period. It is good to do. That is, it is preferable to set the injection end timing FC so that the fuel injected from the fuel injection valve 19 at the injection end timing FC flows into the combustion chamber 5 during the backflow period. For example, the injection end timing FC is set so that the end of the backflow period and the end of the inflow period coincide with each other, and the overlap period between the backflow period and the inflow period can be lengthened. Further, for example, the injection end timing FC is set so that the fuel arrival period falls within the backflow period when the fuel injection period is shorter than the backflow period. In this case, the injection end timing FC can be set so that the integrated value of the absolute value of the exhaust flow velocity in the overlap period between the fuel arrival period and the backflow period is maximized. As described above, the injection start timing FO is set to an angle advanced by the angle amount of the fuel injection period from the injection end timing FC.

FIG. 5 shows an example of the control process of the fuel injection valve 19 that the ECM 100 repeatedly executes periodically (for example, every cycle of the internal combustion engine 1) in the cold state of the internal combustion engine 1. It is assumed that the ECM 100 sets the intake valve 8 and the exhaust valve 9 at the valve timing (see FIG. 3) according to the cold state of the internal combustion engine 1 via the VTC controller 200. That is, it is assumed that the ECM 100 is set so that the valve O / L period is between the exhaust top dead center TDC and the intake bottom dead center BDC.

In step S1 (abbreviated as "S1" in the figure; the same applies hereinafter), the ECM 100 calculates the fuel injection amount required in the cold state of the internal combustion engine 1.

In step S2, the ECM 100 sets the fuel injection period including the injection start timing FO and the injection end timing FC. First, the ECM 100 calculates the fuel injection time from the fuel injection amount calculated in step S1 based on the injection characteristics of the fuel injection valve 19, and fuels based on the engine rotation speed NE calculated using the crank angle signal CRANK. Convert the injection time to the fuel injection period.

Then, the ECM 100 sets the injection end timing FC so that the fuel injected from the fuel injection valve 19 at the injection end timing FC flows into the combustion chamber 5 during the valve O / L period of FIG. When the ECM 100 stores the data of the backflow period of FIG. 4 in advance, the fuel injected from the fuel injection valve 19 at the injection end timing FC flows into the combustion chamber 5 during the backflow period. The injection end timing FC can be set.

Further, the ECM 100 sets the angle advanced by the angle amount of the fuel injection period from the injection end timing FC as the injection start timing FO.

In step S3, the ECM 100 outputs an injection signal including the fuel injection period, the injection start timing FO, and the injection end timing FC as the operation signal of the fuel injection valve 19.

According to the control device and control method of the internal combustion engine 1 according to the first embodiment, the fuel injected from the fuel injection valve 19 at the injection end timing FC burns during the valve O / L period (or backflow period) of FIG. The injection end timing FC is set so as to flow into the chamber 5. Therefore, since the inflow of fuel into the combustion chamber 5 is restricted at least after the exhaust valve 9 is closed, the fuel collision with the inner wall surface of the cylinder 2A due to the intake synchronous injection is effective with the so-called high temperature air curtain due to the backflow exhaust. Can be reduced. As a result, fuel adhesion to the inner wall surface of the cylinder 2A is suppressed and unburned fuel is reduced, so that it is possible not only to improve fuel efficiency but also to suppress an increase in PN in the cold state of the internal combustion engine 1.

[Second Embodiment]
Next, a second embodiment for carrying out the present invention will be described with reference to FIGS. 6 and 7. In this embodiment, the points different from those of the first embodiment will be described, and the same reference numerals will be given to the same configurations as those of the first embodiment, and the description thereof will be omitted or simplified. The same applies to the following embodiments.

FIG. 6 shows a setting example of the fuel injection period in which the injection start timing FO and the injection end timing FC are changed in FIG. FIG. 7 shows an example of setting the injection start timing FO according to the required arrival time.

With respect to the fuel injected from the fuel injection valve 19 in the cold state of the internal combustion engine 1, the backflow exhaust from the exhaust port 3B suppresses fuel adhesion to the inner wall surface of the cylinder 2A, and the inner wall of the intake port 3A and the intake valve 8 It is preferable to suppress fuel adhesion to the umbrella portion 8a and the like. Therefore, as shown in FIG. 6, the fuel injected from the fuel injection valve 19 at the injection start timing FO may flow into the combustion chamber 5 at the beginning of the valve O / L period. Therefore, as shown in FIG. 7, the injection start timing FO of the fuel injection valve 19 is an angle advanced by an angle amount Δθ1 corresponding to the required arrival time from the valve opening timing IVO of the intake valve 8 (ideal injection start timing). Is set to.

Although not shown, when the data regarding the backflow period shown in the lower part of FIG. 6 is acquired in advance, the fuel injected from the fuel injection valve 19 at the injection start timing FO enters the combustion chamber 5 at the beginning of the backflow period. It is good to flow in. Therefore, the injection start timing FO of the fuel injection valve 19 is set to an angle advanced by an angle amount corresponding to the required arrival time from the beginning of the backflow period.

The arrival time is the intake flow velocity of the intake port 3A such as the intake pressure PS, the intake air amount Q, and the engine rotation speed NE with respect to the injection fuel speed calculated from the injection characteristics of the fuel injection valve 19 such as the fuel pressure and the injection hole diameter. May change under the influence of parameters related to. That is, when the intake flow velocity of the intake port 3A increases, the arrival time may become shorter, while when the intake flow velocity decreases, the arrival time may become longer. Therefore, as shown in FIG. 7, the ideal injection start timing changes according to the increase / decrease of the angle amount Δθ1 that changes depending on the length of the arrival time. That is, the ideal injection start timing is retarded as the arrival time becomes shorter, while it advances as the arrival time becomes longer. Therefore, the injection end timing FC is set to the ideal injection start timing according to the change in the arrival required time.

By the way, when the injection start timing FO is set to the ideal injection start timing according to the change in the arrival time as described above, the injection end timing FC is only the length of the fuel injection period from the set injection start timing FO. It is set to a retarded angle. The fuel injected from the fuel injection valve 19 at the injection end timing FC set in this way also needs to flow into the combustion chamber 5 during the valve O / L period of FIG. However, depending on the length of the fuel injection period, it is assumed that the fuel injected from the fuel injection valve 19 at the injection end timing FC does not flow into the combustion chamber 5 during the valve O / L period. That is, as shown by the thick broken line in FIG. 6, it is assumed that the end of the inflow period is later than the valve closing timing EVC of the exhaust valve 9. In this case, for example, by adjusting the injection end timing FC by one of the following methods, the inflow of fuel into the combustion chamber 5 after the valve closing timing EVC of the exhaust valve 9 is restricted and the inside of the cylinder 2A. Fuel adhesion to the wall surface can be suppressed.

As the first method, as shown in FIG. 8, first, the injection end timing FC is advanced and reset so that the end of the inflow period is the valve closing timing EVC of the exhaust valve 9. Specifically, the injection end timing FC is reset to an angle advanced by an angle amount Δθ1 corresponding to the required arrival time from the valve closing timing EVC of the exhaust valve 9. The value of the required arrival time at this time is determined in consideration of the parameters related to the intake flow velocity of the intake port 3A as described above. Then, the injection start timing FO is reset to an angle advanced by the length of the fuel injection period from the reset injection end timing FC, that is, an angle advanced from the ideal injection start timing. In short, the fuel injection period is reset as a whole by advancing according to the amount of advance of the injection end timing FC.

As a second method, when the fuel pressure can be controlled by a fuel pump that pumps fuel to the fuel injection valve 19, the injection start timing is such that the inflow period coincides with the valve O / L period, as shown in FIG. The FO and the injection end timing FC are reset. That is, the injection start timing FO is reset so that the fuel injected at the injection start timing FO flows into the combustion chamber 5 at the valve opening timing IVO of the intake valve 8. Further, the injection end timing FC is reset so that the fuel injected by the injection end timing FC flows into the combustion chamber 5 at the valve closing timing EVC of the exhaust valve 9. The length of the new fuel injection period defined by the injection start timing FO and the injection end timing FC reset in this way is shortened as compared with the fuel injection period before the reset due to the shortening of the inflow period. Therefore, the fuel pressure is increased so that the required fuel injection amount can be injected in a new fuel injection period. Since the arrival time is shortened when the fuel pressure is increased, the injection start timing FO and the injection end timing FC are reset in consideration of the shortened arrival time.

As a third method, as shown in FIG. 10, the closing timing of the exhaust valve 9 is such that the fuel injected from the fuel injection valve 19 at the injection end timing FC flows into the combustion chamber 5 during the valve O / L period. The EVC is retarded.

As described above, the injection start timing FO of the fuel injection valve 19 can be set to an angle advanced by an angle amount corresponding to the required arrival time from the beginning of the backflow period. Therefore, depending on the length of the fuel injection period, it is assumed that the fuel injected at the injection end timing FC does not flow into the combustion chamber 5 during the backflow period. In this case, by adjusting the injection end timing FC by a method according to the first and second methods described above, the inflow of fuel into the combustion chamber 5 after the backflow period is restricted and the inside of the cylinder 2A. Fuel adhesion to the wall surface can be suppressed. However, in the first and second methods described above, the "exhaust valve closing timing EVC" is read as "the end of the backflow period", and the "valve O / L period" is read as the "backflow period".

When the fuel injection period is shorter than the backflow period, it is not necessary to set the injection start timing FO of the fuel injection valve 19 to an angle advanced by an angle amount corresponding to the required arrival time from the start of the backflow period. In this case, the injection start timing FO and the injection end timing FC are set with priority given to the fact that the fuel arrival period falls within the backflow period.

The ECM100 sets the injection start timing FO and the injection end timing FC in step S2 of FIG. 5 as follows.

First, the ECM 100 calculates the arrival required time based on the parameters related to the intake flow velocity of the intake port 3A, and sets the ideal injection start timing corresponding to the calculated arrival required time as the injection start timing FO (see FIG. 7). Then, the ECM 100 sets an angle retarded by the length of the fuel injection period from the set injection start timing FO as the injection end timing FC.

When the injection end timing FC is after the valve O / L period, the injection end timing FC is optimized by any of the above first to third methods. When the injection end timing FC is after the regurgitation period, the injection end timing FC is optimized according to the first or second method described above.

According to the control device and control method of the internal combustion engine 1 according to the second embodiment, in addition to setting the injection end timing FC as in the first embodiment, the injection start timing FO is set as follows. .. That is, the injection start timing FO is set so that the fuel injected from the fuel injection valve 19 at the injection start timing FO flows into the combustion chamber 5 at the beginning of the valve O / L period (or backflow period) of FIG. .. Therefore, not only the fuel adhesion to the inner wall surface of the cylinder 2A due to the intake synchronous injection is suppressed, but also the fuel adhesion to the inner wall surface of the intake port 3A is suppressed. As a result, the amount of unburned fuel is reduced, the suppression of the increase in PN in the cold state of the internal combustion engine 1 is promoted, and the fuel consumption can be further improved.

[Third Embodiment]
Next, a third embodiment for carrying out the present invention will be described with reference to FIGS. 11 to 13. In the present embodiment, the setting of the injection end timing FC of the first embodiment is further embodied. Specifically, the present invention relates to a setting method according to the engine rotation speed NE of the injection end timing FC.

FIG. 11 shows the influence of the change in the engine rotation speed NE on the inflow period. FIG. 11A shows a case where the engine rotation speed NE is relatively low, and FIG. 11B shows a case where the engine rotation speed NE is relatively high. .. FIG. 12 shows a setting example of the injection end timing FC according to the engine rotation speed NE.

As shown in FIGS. 11A and 11B, if the same injection amount of fuel is injected with constant injection characteristics during each time corresponding to the fuel injection period and the fuel arrival period, the engine rotation speed NE is high or low. There is almost no change regardless. On the other hand, the time corresponding to the valve O / L period becomes shorter as the engine speed NE increases. For example, if the engine rotation speed NE is doubled, the time corresponding to the valve O / L period is halved. Therefore, as shown in FIGS. 11A and 11B, the time from the injection end timing FC to the end of the valve O / L period, that is, the valve closing timing EVC of the exhaust valve 9, also becomes shorter as the engine speed NE increases. .. That is, the time ΔtH from the injection end timing FC when the engine rotation speed NE is relatively high to the valve closing timing EVC of the exhaust valve 9 is shorter than the time ΔtL when the engine rotation speed NE is relatively low.

By the way, when the injection speed of the fuel injected from the fuel injection valve 19 having a constant injection characteristic is more dominant than the intake flow velocity of the intake port 3A as an influential factor affecting the arrival time. , The time required to reach the engine is less likely to change depending on the level of the engine rotation speed NE. In this case, even if the arrival time is within the time ΔtL when the engine speed NE is relatively low (see FIG. 11A), the arrival time is when the engine speed NE is relatively high. It may not fit within the time ΔtH (see FIG. 11B). This is because when the engine speed NE is relatively high, the fuel injected from the fuel injection valve 19 at the injection end timing FC does not flow into the combustion chamber 5 during the valve O / L period, and the fuel enters the inner wall surface of the cylinder 2A. Means that it becomes easy to adhere.

Therefore, the injection end timing FC needs to be set to the limit injection end timing shown in FIG. 12 or an angle advanced from this. The limit injection end timing is the most retarded angle among the injection end timing FCs at which the fuel injected from the fuel injection valve 19 can flow into the combustion chamber during the valve O / L period at each engine rotation speed NE. Assuming that the required arrival time is constant regardless of the level of the engine rotation speed NE, the limit injection end timing is an angle advanced by an angle amount Δθ2 according to the required arrival time from the valve closing timing EVC of the exhaust valve 9. Is set as. This amount of angle Δθ2 increases in proportion to the increase in the engine rotation speed NE.

FIG. 13 shows an additional process inserted into the control process of the fuel injection valve 19 of FIG. In step S2 of FIG. 5, in step S2 of FIG. 5, the fuel injected from the fuel injection valve 19 at the injection end timing FC flows into the combustion chamber 5 during the valve O / L period (or backflow period) of FIG. The injection end timing FC is set so as to be performed. Further, in step S2, the ECM 100 sets an angle advanced from the injection end timing FC by the length of the fuel injection period as the injection start timing FO. Then, the ECM 100 executes steps S2a and S2b as additional processing before executing step S3 of FIG.

In step S2a, the ECM 100 determines whether or not the set injection end timing FC is later than the limit injection end timing of FIG. 12 based on the engine rotation speed NE calculated using the crank angle signal CRANK. Then, when the ECM 100 determines that the set injection end timing FC is later than the limit injection end timing (YES), the process proceeds to step S2b. On the other hand, if the ECM 100 determines that the set injection end timing FC is before the limit injection end timing (NO), step S2a is omitted and the process proceeds to step S3.

In step S2b, the ECM100 corrects the set injection end timing FC to the limit injection end timing or an angle advanced from this. Further, the ECM 100 corrects the injection start timing FO to an angle advanced by the length of the fuel injection period from the corrected injection end timing FC in accordance with the correction of the injection end timing FC.

Even when the injection end timing FC of the fuel injection valve 19 is set to an angle advanced by an angle amount corresponding to the required arrival time from the end of the backflow period, the ECM100 sets the engine rotation speed NE as described above. In consideration of this, the fuel injection valve 19 is controlled. However, "valve O / L period" is read as "backflow period", and "valve closing timing EVC of exhaust valve 9" is read as "end of backflow period".

According to the control device and control method of the internal combustion engine 1 according to the third embodiment, the fuel injected from the fuel injection valve 19 at the injection end timing FC burns during the valve O / L period (or backflow period) of FIG. The injection end timing FC is set in consideration of the engine rotation speed NE so as to flow into the chamber 5. Therefore, since the inflow of fuel into the combustion chamber 5 is restricted at least after the exhaust valve 9 is closed, it is possible to effectively reduce the fuel adhesion to the inner wall surface of the cylinder 2A due to the intake synchronous injection by the backflow exhaust. it can. As a result, fuel adhesion to the inner wall surface of the cylinder 2A is suppressed and unburned fuel is reduced, so that it is possible to further improve fuel efficiency and further suppress the increase in PN in the cold state.

[Fourth Embodiment]
Next, a fourth embodiment for carrying out the present invention will be described with reference to FIG. In the fourth embodiment, the setting of the injection end timing FC of the first embodiment is further embodied. Specifically, the present invention relates to a method of setting an injection end timing FC when the vehicle is accelerated in a cold state of the internal combustion engine 1.

FIG. 14 shows a setting example of the injection end timing FC according to the change in the accelerator opening. In FIG. 14, (a) is a time change of the accelerator opening ACC, (b) is a time change of the valve closing timing EVC of the exhaust valve 9, (c) is a time change of the valve O / L period, and (d) is an injection. The time change of the end timing FC is shown. In FIG. 14C, a positive value of the valve O / L period indicates that the two valve opening periods of the intake valve 8 and the exhaust valve 9 overlap. Further, a negative value of the length of the valve O / L period indicates that the two valve opening periods of the intake valve 8 and the exhaust valve 9 do not overlap, and indicates that the valve O / L period does not occur. ing.

When the accelerator opening ACC detected from the output signal of the accelerator opening sensor 22 increases (see FIG. 14 (a)), the ECM 100 exhaust valve 9 via the VTC controller 200 according to the amount of increase in the accelerator opening ACC. The valve closing timing EVC is advanced (see FIG. 14B). Then, the valve O / L period is reduced according to the amount of advance of the valve closing timing EVC of the exhaust valve 9 (see FIG. 14 (c)). However, since the interval between the injection end timing FC and the end of the valve O / L period becomes short, the fuel injected from the fuel injection valve 19 at the injection end timing FC does not flow into the combustion chamber 5 within the valve O / L period. There is a risk. Therefore, the ECM 100 also advances the injection end timing FC according to the amount of advance when the valve closing timing EVC of the exhaust valve 9 is advanced.

When the valve closing timing EVC of the exhaust valve 9 is advanced as the accelerator opening ACC increases (see FIG. 14B), the valve closing timing EVC of the exhaust valve 9 and the valve opening timing IVO of the intake valve 8 are changed. Consistently, the valve O / L period goes to zero (see FIG. 14 (d)). The injection end timing FC is advanced according to the advance amount of the valve closing timing EVC of the exhaust valve 9 until the valve O / L period becomes zero.

In step S2 of FIG. 5, in step S2 of FIG. 5, the fuel injected from the fuel injection valve 19 at the injection end timing FC flows into the combustion chamber 5 during the valve O / L period (or backflow period) of FIG. The injection end timing FC is set so as to be performed. Then, the ECM 100 also advances the injection end timing FC according to the amount of advance when the valve closing timing EVC of the exhaust valve 9 is advanced as the accelerator opening degree ACC increases. Further, in step S2, the ECM 100 sets an angle advanced by the angle amount of the fuel injection period from the injection end timing FC as the injection start timing FO.

According to the control device and control method of the internal combustion engine 1 according to the fourth embodiment, the fuel injected from the fuel injection valve 19 at the injection end timing FC burns during the valve O / L period (or backflow period) of FIG. The injection end timing FC is set so as to flow into the chamber 5 while considering the advancement of the valve closing timing EVC of the exhaust valve 9 as the accelerator opening ACC increases. Therefore, since the inflow of fuel into the combustion chamber 5 is restricted at least after the exhaust valve 9 is closed, it is possible to effectively reduce the fuel adhesion to the inner wall surface of the cylinder 2A due to the intake synchronous injection by the backflow exhaust. it can. As a result, fuel adhesion to the inner wall surface of the cylinder 2A is suppressed and unburned fuel is reduced, so that it is possible to further improve fuel efficiency and further suppress the increase in PN in the cold state.

Although the contents of the present invention have been specifically described above with reference to the preferred embodiments, those skilled in the art can use various modifications based on the basic technical ideas and teachings of the present invention as described below. It is self-evident that it can be obtained.

The valve O / L period in the above embodiment was a cold valve O / L period in which the valve timings of the intake valve 8 and the exhaust valve 9 were set according to the cold state of the internal combustion engine 1. When the valve timings of the intake valve 8 and the exhaust valve 9 are set corresponding to the high load operation region including the full load (engine load TP equivalent to the full throttle opening) instead of the cold valve O / L period. The valve O / L period at the time of high load can be set. Alternatively, instead of the cold valve O / L period, the high rotation valve O / L period can be set when the engine rotation speed NE is set corresponding to the relatively high high rotation operation region. That is, in the high load or high rotation operation region, the valve opening timing IVO of the intake valve 8 is set to advance with respect to the exhaust top dead center TDC, and the valve O / L period at high load or high rotation is the exhaust top dead center. Even if it is started in a range advanced from the TDC, the same effect as that of the above-described embodiment is obtained.

In the high load or high rotation operation region, the injection end timing FC is the period (or backflow period) after the exhaust top dead center TDC in the valve O / L period when the fuel injected at this timing is high load or high rotation. Is set to flow into. As a result, even in the high load operation region where the fuel injection amount increases and the high rotation operation region where the vaporization time becomes short, the fuel collision with the inner wall surface of the cylinder 2A at the time of intake synchronous injection is caused by the backflow exhaust from the exhaust port 3B. It is reduced by a high temperature air curtain. Therefore, since fuel adhesion to the inner wall surface of the cylinder 2A is suppressed, it is possible not only to improve fuel efficiency but also to suppress an increase in PN. In short, in a specific engine operating state where there is a concern that fuel adhesion to the inner wall surface of the cylinder 2A may increase, the injection end timing FC is set to the exhaust top dead center TDC or later during the valve O / L period of the intake valve and the exhaust valve. It may be set to a period (or a backflow period). As described above, the specific engine operating state includes, for example, a cold state of the internal combustion engine 1 and a high load or high rotation operating region.

On the other hand, in the engine operating state where the possibility of fuel adhering to the inner wall surface of the cylinder 2A is relatively low, the injection end timing FC is set to the period after the exhaust top dead center TDC in the valve O / L period of the intake valve and the exhaust valve. It is not necessary to set (or backflow period). Such an engine operating state includes, for example, a partial low load region larger than the idle load after the completion of warming up of the internal combustion engine 1.

The internal combustion engine 1 uses a variable valve timing mechanism 21 composed of an intake variable mechanism 21a and an exhaust variable mechanism 21b, but the present invention is not limited to this, and can be configured as follows. That is, in the internal combustion engine 1, if a part or all of the valve O / L period can be set between the exhaust top dead center TDC and the intake bottom dead center BDC, either the intake variable mechanism 21a or the exhaust variable mechanism 21b. Either one may be omitted. Further, in the internal combustion engine 1, the valve timings of the intake valve 8 and the exhaust valve 9 are fixed, that is, even if the configuration does not include the variable valve timing mechanism 21, part or all of the valve O / L period is When it is included between the exhaust top dead center TDC and the intake bottom dead center BDC, the injection end timing FC and the injection start timing FO may be set as described above.

The ECM 100 and the VTC controller 200 may be configured separately or integrally.

Note that the technical ideas described in the first to fourth embodiments can be used in combination as appropriate as long as there is no contradiction.

For example, in combination with the third embodiment and the fourth embodiment, while considering an increase in the engine rotation speed NE and an advancement of the valve closing timing EVC of the exhaust valve 9 due to an increase in the accelerator opening ACC. , The injection end timing FC can be set to advance.

1 ... Internal combustion engine, 3A ... Intake port, 5 ... Combustion chamber, 8 ... Intake valve, 9 ... Exhaust valve, 19 ... Fuel injection valve, NE ... Engine rotation speed, TDC ... Exhaust top dead center, IVO ... Intake valve opening Valve timing, EVC ... Exhaust valve closing timing, EO ... Injection start timing, EC ... Injection end timing

Claims

The valve overlap period of the intake valve and the exhaust valve of the internal combustion engine is set after the exhaust top dead point, and the injection end timing of the fuel injection valve that injects fuel into the intake port opened and closed by the intake valve is set to the fuel. An internal combustion engine control device that sets the fuel injected from the injection valve at the injection end timing so as to flow into the combustion chamber during the valve overlap period.
The injection start timing of the fuel injection valve is set so that the fuel injected from the fuel injection valve at the injection start timing flows into the combustion chamber at the timing when the intake valve opens. The control device for an internal combustion engine according to.
The control device for an internal combustion engine according to claim 1, wherein the injection end timing is corrected in advance according to an increase in the rotational speed of the internal combustion engine.
The timing at which the exhaust valve closes when the vehicle accelerates in the cold state of the internal combustion engine is advanced, and the timing at which the exhaust valve closes is advanced until the valve overlap period becomes zero. The control device for an internal combustion engine according to claim 1, wherein the injection end timing is advanced according to the advance amount at the time.
Data of the backflow period, which is the period during which the exhaust gas flows back to the combustion chamber in the valve overlap period, is stored in advance.
The injection end timing is set so that the fuel injected from the fuel injection valve at the injection end timing flows into the combustion chamber during the backflow period based on the data of the backflow period. The control device for an internal combustion engine according to 1.
The internal combustion engine according to claim 5, wherein the injection end timing is set so that the integrated value of the flow velocity of the exhaust gas during the period in which the fuel injected from the fuel injection valve flows into the combustion chamber becomes maximum. Control device.
The control device according to claim 1, wherein the injection fuel timing is set in a cold state of the internal combustion engine.
If the injection end timing is later than the timing delayed by the angle amount of the fuel injection period with respect to the injection start timing, the setting of the injection start timing is canceled and the injection end timing is set. The control device for an internal combustion engine according to claim 2, which has priority.
When the injection end timing is later than the timing delayed by the angle amount of the fuel injection period with respect to the injection start timing, the fuel pressure of the fuel is increased to shorten the fuel injection period. Item 2. The control device for an internal combustion engine according to item 2.
According to claim 2, when the injection end timing is later than the timing at which the injection end timing is retarded by the angle amount of the fuel injection period with respect to the injection start timing, the timing at which the exhaust valve closes is delayed. The control device for an internal combustion engine as described.
An internal combustion engine control device that controls a fuel injection valve that injects fuel into an intake port that is opened and closed by an internal combustion engine intake valve.
When the valve overlap period of the intake valve and the exhaust valve is a period including after the exhaust top dead center, the injection end timing of the fuel injection valve is set to the valve overlap period after the exhaust top dead center. A control device for an internal combustion engine, which comprises a timing setting means.
The valve overlap period of the intake valve and the exhaust valve of the internal combustion engine is set after the exhaust top dead point, and the injection end timing of the fuel injection valve that injects fuel into the intake port opened and closed by the intake valve is set to the fuel. A control method for an internal combustion engine, in which fuel injected from an injection valve at the injection end timing is set to flow into a combustion chamber during the valve overlap period.