JPH01247732A - Control device for fuel injection of internal combustion engine - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a fuel injection amount control device for an internal combustion engine that is effective when controlling an increase in fuel supply amount such as acceleration increase.

[Prior Art] It has been known that, for example, when a vehicle internal combustion engine transitions to an accelerating operation state, increase correction control is performed using synchronous increase injection or non-synchronized increase injection to improve the output responsiveness of the internal combustion engine. There is. By the way, in the increase correction control as described above, it is necessary to maintain good responsiveness during acceleration, exhaust characteristics, and drivability. For example, the following techniques have been proposed as such techniques. That is,
(1) The throttle position signal and intake pipe pressure signal are input into the electronic control circuit, and based on changes in each signal, a fuel injection command signal is sent to the fuel injection device so that the air-fuel ratio during the transient period is set to an ideal value. Fuel-injected engine that maintains optimal output and emission drivability
(Japanese Unexamined Patent Publication No. 58-48725).

(2) comprising means for determining the fuel supply amount during acceleration in accordance with the vehicle running speed, and means for supplying fuel to the engine in accordance with the determined fuel supply amount during acceleration when acceleration driving is requested; ``Fuel supply amount control device for internal combustion engine'' that improves both drivability and response during acceleration (Japanese Patent Laid-Open No. 194052/1983).

[Problem to be Solved by the Invention] By the way, in the conventional technology as described above, the acceleration state is determined based on the throttle valve opening degree and the amount of change in load, and the increase correction amount is determined in accordance with the amount of change. ,or,
A predetermined increase correction amount was used depending on the traveling speed. However, in general, as the vehicle speed increases, the steady running load (load during steady road running) increases. In this case, when the load of the internal combustion engine deviates from the steady running load by more than a predetermined amount, asynchronous injection or an increase in the same amount is performed to compensate for the amount of fuel adhering to the intake pipe or to compensate for the delay in detecting the amount of change in load. Accelerated increase in dosage is effective. However, when the load is in a region near the steady running load, the amount of adhesion to the intake pipe is a predetermined constant amount of electricity, so there is a problem that the amount of fuel supplied becomes excessive when the amount is increased for acceleration.

In this way, even in the steady running load range where acceleration increase is unnecessary,
Fuel consumption efficiency deteriorated significantly due to acceleration fuel increase such as asynchronous injection or synchronous fuel increase injection.

In addition, in a region near the steady running load, excessive fuel is supplied, which causes disturbances in the air-fuel ratio such as a shift to the excessive layer side, resulting in a problem of deterioration of exhaust characteristics.

Furthermore, if the acceleration amount is not increased appropriately, particularly in operating conditions where the throttle valve opening is small, there is a problem in that sudden changes in output occur, inducing shocks and surges during acceleration that are unpleasant for the occupants.

SUMMARY OF THE INVENTION An object of the present invention is to provide a fuel injection amount control device for an internal combustion engine that can limit unnecessary acceleration increases and execute only necessary acceleration increases to suitably suppress waste of fuel.

[Means for Solving the Problem] The present invention, which has been made to achieve the above object, as illustrated in FIG. A fuel supply means M3 supplies fuel to the internal combustion engine M1 according to an externally commanded supply amount according to the required acceleration state detected by the main operation state detection means M2. control means M4 that determines an increased acceleration supply amount increased by the internal combustion engine M1, and instructs the acceleration increase supply amount to the fuel supply means M3 asynchronously or synchronously with the rotation of the internal combustion engine M1. The fuel injection amount control device for an internal combustion engine further includes a vehicle speed detecting means M5 for detecting the traveling speed of a vehicle driven by the internal combustion engine M1, and the vehicle speed detecting means M
calculation means M6 for calculating a near steady load region which is a load slight fluctuation region near a steady running load of the internal combustion engine M1, which is determined according to the detected vehicle speed of the internal combustion engine M1 detected by the operating state detecting means M2;
load determining means M7 for determining whether or not the load is included in the steady load vicinity region calculated by the calculating means M6; and the required acceleration state detected by the driving state detecting means M2.
The requested acceleration state determining means M8 determines whether or not the slow acceleration request state is a predetermined acceleration state or less, and the driving state detecting means M is determined by the load determining means M7.
It is determined that the load of the internal combustion engine M1 detected in Step 2 is included in the region near the steady load, and the requested acceleration state detected by the operating state detecting means M2 is determined by the requested acceleration state determining means M8 to be the noodle acceleration request. When it is determined that the above-mentioned acceleration increase supply amount is in the state, prohibition of a command to supply the acceleration increase supply amount asynchronously, or a command to synchronously supply a corrected acceleration increase supply amount by reducing the acceleration increase supply amount, Limiting means M9 for instructing the control means M4 to at least one of the
The gist of the present invention is a fuel injection amount control device for an internal combustion engine, characterized by comprising: and.

The operating state detection means M2 detects the operating state of the internal combustion engine M1, including at least the requested acceleration state.

For example, it can be realized by combining an intake pipe pressure sensor, a throttle position sensor, or a rotational speed sensor with various intake air amount sensors.

The fuel supply means M3 supplies fuel to the internal combustion engine M1 according to an externally commanded supply amount. For example, it can be realized by an electromagnetic fuel injection valve, an electronically controlled carburetor capable of supplying bleed air, or the like.

The control means M4 determines the increased acceleration supply amount according to the required acceleration state detected by the operating state detection means M2,
This command commands the fuel supply means M3 to increase the acceleration supply amount asynchronously or synchronously with the rotation of the internal combustion engine M1. For example, a predetermined acceleration increase is determined according to the intake pipe pressure or the rate of increase in the throttle valve opening,
It can be configured to output a command to perform non-synchronized injection or synchronous increasing injection.

The vehicle speed detection means M5 detects the traveling speed of the vehicle driven by the internal combustion engine M1.

This can be realized using a well-known electromagnetic lift-up type vehicle speed sensor.

The calculation means M6 is for calculating a region near a steady load, which is a region of small load fluctuations near the steady running load of the internal combustion engine M1, which is determined according to the vehicle speed detected by the vehicle speed detection means M5. For example, it can be constructed from an arithmetic expression, a map, etc., for calculating a deceleration range discrimination load, an acceleration increase discrimination load, etc., which are determined by taking into consideration variations in throttle valve opening from a steady running load on flat ground with respect to the vehicle speed.

The load determining means M7 determines whether the load of the internal combustion engine M1 detected by the operating state detecting means M2 is included in the steady load vicinity region calculated by the calculating means M6.

For example, the determination can be made by comparing the intake pipe pressure or the throttle valve opening value with a deceleration range determination load, an acceleration increase determination load, or the like.

The required acceleration state determining means M8 is the driving state detecting means M2.
It is determined whether the detected required acceleration state is a slow acceleration required state that is less than or equal to a predetermined acceleration state. For example, it can be configured to compare the intake pipe pressure fluctuation amount, the throttle valve opening fluctuation amount, etc. with a predetermined fluctuation reference amount.

The limiting means M9 means that the load of the internal combustion engine M1 detected by the operating state detecting means M2 is determined by the load determining means M7 to be included in the region near the steady load, and the required acceleration state determining means M8 determines that the load of the internal combustion engine M1 is included in the region near the steady load. When it is determined that the requested acceleration state detected by M2 is a slow acceleration requested state,
This command instructs the control means M4 to prohibit at least one of a command to asynchronously supply the acceleration increase supply amount, or a command to synchronously supply a corrected acceleration increase supply amount by reducing the acceleration increase supply amount. . For example, when the load is included in the region near the steady load and the requested acceleration state is a slow acceleration request state, the instruction to supply the increased supply amount of acceleration asynchronously is prohibited and the increased supply amount of corrected acceleration is supplied synchronously. On the other hand, if the load is included in the region near the steady load, but the requested acceleration state is not the slow acceleration request state, the asynchronous injection collapse or the same-song increased injection amount is determined according to the load. Can be configured.

The control means M4, the calculation means M6, the load determination means M7,
The requested acceleration state determining means M8 and the limiting means M9 are, for example,
This can be realized using independent discrete logic circuits. In addition, for example, in addition to the well-known CPU, ROM,
It may be configured as a logic operation circuit together with a RAM and other peripheral circuit elements, and may implement each of the above means according to a predetermined processing procedure.

[Operations] In the fuel injection amount control device for an internal combustion engine according to the present invention, as illustrated in FIG.
The fuel supply means M determines an increased acceleration supply amount in accordance with the requested acceleration state detected by the fuel supply means M, and supplies the acceleration increase supply amount asynchronously or synchronously with the rotation of the internal combustion engine M1.
Command 3.

On the other hand, the calculating means M6 calculates a region near the steady load, which is a negative range near the steady running load of the internal combustion engine M1, which is determined according to the vehicle speed detected by the vehicle speed detecting means M5. Then, the load determining means M7 determines whether the load detected by the driving state detecting means M2 is included in the steady load vicinity region calculated by the calculating means M6, while the required acceleration state determining means M8 , the operating state detection means M2
It is determined whether the detected requested acceleration state is a slow acceleration state that is less than or equal to a predetermined acceleration state. Here, when the load determining means M7 determines that the load is within the region near the steady running load and the required acceleration state determining means M8 determines that the required acceleration state is a slow acceleration state, the limiting means M9 is activated. , instructing the control means M4 to issue at least one of a command to asynchronously supply the acceleration increase supply amount, or a command to synchronously supply a corrected acceleration increase supply amount obtained by reducing the acceleration increase supply amount; work to do.

That is, when the load is included in a region near a steady load determined according to the vehicle speed ζ, and the requested acceleration state is a slow acceleration state, asynchronous supply of the increased acceleration supply amount is prohibited, or
The acceleration increase supply amount is limited by either synchronous supply of the corrected acceleration increase supply amount, which is a correction of the acceleration increase supply amount by decreasing the acceleration increase supply amount, thereby preventing excessive supply of fuel in a slow acceleration state in a region near a steady load.

Therefore, the fuel injection amount control device for an internal combustion engine of the present invention is as follows:
It works to limit the supplied fuel to an amount compatible with achieving the required acceleration state.

The technical problems of the present invention are solved by each component of the present invention acting as described above.

[Embodiment] Next, a preferred embodiment of the present invention will be described in detail based on the drawings. FIG. 2 shows a system J1 configuration of an engine control device that is an embodiment of the present invention.

As shown in the figure, the engine control device 1 includes an engine 2
and an electronic control unit (hereinafter simply referred to as ECU) that controls it.
It is called. ) consists of 3.

The engine 2 includes a cylinder 4, a piston 5, and a cylinder head 6 to form a combustion chamber 7, and a spark plug 8 is disposed in the combustion chamber 7.

The intake system of the engine 2 includes the combustion chamber 7 and the intake valve 9.
An intake pipe 10 that communicates with the intake pipe 10, an electromagnetic fuel injection valve 11 that is installed in the intake pipe 10 and injects fuel, a surge tank 12 that absorbs the pulsation of intake air, and an intake air amount that is linked to the accelerator pedal. It is composed of a throttle valve 13 and an air cleaner 14 to be adjusted.

The exhaust system of the engine 2 includes an exhaust manifold 15 communicating with the combustion chamber 7 via an exhaust valve (not shown), a catalytic converter 16 filled with a three-way catalyst, and an exhaust pipe 17.

The ignition system of the engine 2 includes an igniter 18 equipped with an ignition coil that outputs the high voltage necessary for ignition, and a distributor that distributes the high voltage generated by the igniter in one day to the spark plugs in conjunction with a crankshaft (not shown). It consists of 19.

The engine control device 1 uses an air cleaner 14 as a detector.
An intake air temperature sensor 21 is provided inside to measure the intake air temperature, and a throttle position sensor 22 is linked to the throttle valve 13 to detect the throttle valve opening.
, an idle switch 23 that detects the fully open state of the throttle valve 13, an intake pipe pressure sensor 24 that communicates with the surge tank 12 and detects the intake pipe pressure, and a cylinder block 4.
a water temperature sensor 25 installed in the cooling system of a to detect the cooling water temperature; an oxygen moisture sensor 26 installed in the exhaust manifold 15 to detect the residual oxygen concentration in the exhaust; and one revolution of the camshaft of the distributor 19. That is, the cylinder discrimination sensor 27 outputs a reference signal every two rotations of the crankshaft (not shown), and every 1/24 rotation of the camshaft of the distributor 19, that is, every integral multiple of the crank angle 06 to 30 degrees. A rotation angle sensor 28 that also serves as a rotation speed sensor that outputs a rotation angle signal, and an electromagnetic pickup type vehicle speed sensor 3 that detects the rotation speed of an output shaft of a transmission 29 connected to a crankshaft (not shown) of the engine 2.
0.

Detection signals from each of the sensors and switches described above are input to the ECU 3, and the ECU 3 controls the engine 2. The ECU 3 is configured as a logic operation circuit mainly including a CPU 3a, a ROM 3b, a RAM 3c, and a backup RAM 3d, and is connected to a human output section 3f via a common bus 3e to perform human output with the outside. The CPU 3a manually outputs the detection signals of the above-mentioned sensors and switches via the human output section 3f.

On the other hand, the CPU 3a drives and controls the fuel injection valve 11 and the igniter 1 through the human output section 3f.

Next, the asynchronous injection control process executed by the ECU 3 will be explained based on the flowcharts shown in FIG. 3, the acceleration increase coefficient calculation process in FIG. 5, and the fuel injection control process in FIG. 7.

First, the asynchronous injection control process will be explained based on the flowchart shown in FIG. This asynchronous injection control process
After starting U3, a predetermined time (for example, 12 [m5ec])
executed every time. First, in step 100, a process is performed to read the intake pipe pressure PM(n) and vehicle speed V at the time of the current process based on the detection signals of each sensor described above. In the subsequent step 110, the deceleration region determination pressure PMI (indicated by a dashed line in the figure) is determined according to the vehicle speed V according to a map as shown in FIG. 4, which is stored in the ROM 3b in advance.
Processing to calculate is performed. Here, deceleration region determination pressure P
MI is determined based on the steady running range pressure PMR/L (shown as a solid line in the figure) (corresponds to the load during steady running on flat ground), and is determined based on the deceleration range judgment pressure PMI and the throttle valve fully open pressure PMLL (shown as a solid line in the figure). ) (shown by a broken line in the figure) (corresponds to the load when the throttle valve is fully open) is the deceleration region.

Next, the process proceeds to step 120, where the intake pipe pressure P at the time of current processing is
A process is performed in which the intake pipe pressure PM(n-1) at the previous process is subtracted from M(n) to calculate the negative pressure change amount ΔPM.

In the following step 130, the intake pipe pressure PM during the current processing is
It is determined whether or not (n) exceeds the deceleration range determination pressure PM1. If the determination is affirmative, the process proceeds to step 170, and if the determination is negative, the process proceeds to step 140. In step 140, which is executed when it is determined that the deceleration region is present, it is determined whether the negative pressure change amount ΔPM exceeds the negative pressure change amount determination value PMA (a value set small), and an affirmative determination is made. If so, the process advances to step 160, while if the determination is negative, the process advances to step 150. When it is determined that the engine is in a state of slight acceleration, the process proceeds to step 150 without performing non-uniform injection.
In conjunction with the next treatment, the intake pipe pressure PM (n-
After performing the process of updating 1) with the intake pipe pressure PM(n) during the current process, the asynchronous injection control process ends on -1.

On the other hand, in step 160, which is executed when it is determined in step 140 that the overcrowding acceleration state is present, a process is performed in which the intake pipe pressure offset value PMOFFSET is set to the negative pressure change amount determination value PMA, that is, to a small 1st shift. After performing this, the process proceeds to step 190. Also, step 13 above
In step 170, which is executed when it is determined that the deceleration region is near the steady load at It is determined whether or not it exceeds the value .), and if the determination is affirmative, the process proceeds to step 180; if the determination is negative, it is assumed that the vehicle is in a slow acceleration state, and the non-uniform injection is not performed, as described above. Proceed to step 150. In step 180, which is executed when it is determined that the state is in a deceleration region near a steady load but in a rapid acceleration state, the intake pipe pressure offset value P is
After performing the process of setting MOFF5ET to the negative pressure change amount determination value PMB, that is, to a large value, step 190
Proceed to. In step 190, the asynchronous injection amount is calculated using the following formula (1
) is performed.

(ΔPM-PMOFFSET) / (PMSM・8/16) x PM (n)X Kl (1) However, PMSM is the average value of the intake pipe pressure PM, and K1 is the injection coefficient.

In the subsequent step 195, a control signal is sent to the fuel injector 1 to open the fuel injector 11 for an asynchronous injection time that enables IT# stripping of the asynchronous injection amount calculated in step 190.
After performing the process of outputting to 1, the step 150 described above is performed.
After that, the main simultaneous injection control process ends. Thereafter, the main simultaneous injection control process repeats steps 100 to 195 at predetermined time intervals.

Next, the acceleration increase coefficient calculation process executed in this embodiment will be explained based on the flowchart shown in FIG. This acceleration increase coefficient calculation process is executed every predetermined crank angle (for example, 180['CA]') after the ECU 3 is started. First, in step 200, a process is performed to read intake pipe pressure PM, vehicle speed (2), and rotation angle signals based on detection signals from each sensor described above. In the following step 210, a process is performed to calculate the engine rotational speed Ne from the rotational angle. Next, the process proceeds to step 220, in which a basic fuel injection time TP is calculated according to a map shown in FIG. 6, which is stored in advance in the ROM 3b, according to the intake pipe pressure PM and the rotational speed Ne. In the subsequent step 230, a process is performed to calculate the constant pressure PM2 for each acceleration increase region (indicated by a two-dot chain line in the figure) according to the vehicle speed (2) according to the map shown in FIG. 4 mentioned above. Here, the constant pressure PM2 for each acceleration increase region is the steady driving region pressure PMR.
/L (shown by a solid line in the figure) (corresponds to the load during steady running on flat ground), and the area where the acceleration increase area determination pressure PM2 or higher is the acceleration area.

Next, the process proceeds to step 240, where a process is performed to calculate the basic fuel injection time smoothed value TPM(n) as shown in the following equation (2).

TPM (n) = [((m-1)XTPM (n-1)) +TP] /
m... (2) However, in TPM (n-1), the basic fuel injection time rounded value m at the time of the previous processing is a constant, for example, m=64.

In the following step 250, the basic fuel injection time rounded value TPM (II) is subtracted from the basic fuel injection time TP, and
A process of calculating the basic fuel injection time variation amount ΔTPM is performed. Next, the process proceeds to step 260, in which it is determined whether or not the intake pipe pressure PM during the current process exceeds the constant pressure PM2 for each acceleration increase region.If the judgment is affirmative, the process proceeds to step 265; on the other hand, if the judgment is negative, the process proceeds to step 285. , respectively. In step 265, which is executed when it is determined that it is not in the acceleration range, the basic fuel injection time change amount ΔTPM is determined as the acceleration determination (direct TP
It is determined whether or not it exceeds B (largely set value). If the determination is affirmative, the process proceeds to step 275. On the other hand, if the determination is negative, the process proceeds to step 27, assuming that the state is in a slow acceleration state.
In order to proceed to 0 and not perform acceleration increase, the acceleration increase coefficient K
After setting ACC to a value of 1.0, the present acceleration increase coefficient calculation process is terminated. On the other hand, step 27 is executed when it is determined that the vehicle is not in the acceleration range but is in a rapid acceleration state.
5, the basic fuel injection time offset) f+mTPOF'
After performing the process of setting FSET to acceleration determination (i PMB, that is, to a large value), the process proceeds to step 280. In step 280, the process of calculating the acceleration increase coefficient KACC as shown in the following equation (3) is performed. It will be done.

KACC= (ΔTPM-TPOFFSET)/(2
,048)... (3) After that, on -day, this acceleration increase coefficient calculation process ends.

On the other hand, in step 285, which is executed when it is determined in step 260 that the current is in the acceleration range, the basic fuel injection time change amount ΔTPM is set to the acceleration determination value TPA (a value set smaller than the acceleration determination value TPB). ), and if a positive determination is made, the process proceeds to step 290, while if a negative determination is made, the process proceeds to step 295. Step 290 executed when it is determined that the normal acceleration state is present.
Now, the basic fuel injection time offset value TPOFFSET
After performing the process of setting the acceleration determination value TPA to a small value, the process goes through step 280 described above in order to calculate the acceleration increase coefficient KACC, and then ends the acceleration increase coefficient calculation process.

On the other hand, when it is determined that the state is in a slight acceleration state, the process proceeds to step 295 without performing a synchronous increase, and the acceleration increase coefficient KA
After setting CC to a value of 1.0, the acceleration increase coefficient calculation process ends on -1. Thereafter, the acceleration increase coefficient calculation process repeats steps 200 to 295 at every predetermined crank angle.

Next, the fuel injection control process will be explained based on the flowchart shown in FIG. This fuel injection control wholesale process is performed by the ECU
3, every predetermined crank angle (for example, 360 [
°CA] ') is executed. First, in step 300, a process is performed to read various data including the acceleration increase coefficient KACC mentioned above and the well-known air-fuel ratio feedback correction coefficient FAF. In the following step 310, various well-known correction coefficients KE, such as a warm-up increase coefficient, and an invalid injection time KV are
Engine 2. Depending on the operating state of the engine, calculation processing is performed by interpolation according to a map stored in advance in the ROM 3b. Next, the process proceeds to step 320, where a process of calculating the actual fuel injection time TAU as shown in the following equation (4) is performed.

TAU = TP ◆FAF ◆KACC-KE+KV... (4
) In the subsequent step 330, after outputting the control f, l[j signals to the fuel injection valve 11 to open the fuel injection valve 11 for the actual fuel injection time TAU calculated in the above step 320, The fuel injection control process ends. From then on, this fuel injection control process repeats step 3 at each predetermined crank angle.
Repeat steps 00-330.

Note that in this embodiment, the engine 2 is the internal combustion engine M1,
The intake pipe pressure sensor 24 corresponds to the operating state detection means M2, the fuel injection valve 11 corresponds to the fuel supply means M3, and the ECU
3 and the processing steps (100,
120,160,190,195,200~220,2
90, 280) functions as the control means M4. Also,
The vehicle speed sensor 30 corresponds to the vehicle speed detection means M5, and the ECU 3
and step (11) of the processing executed by the ECU 3.
0,230) as the calculation means M6, step (130
, 260) as the load determining means M7, step (17
0,265) is the required acceleration state determining means M8, step (
170, 265, 270) each function as the limiting means M8.

As explained above, according to this embodiment, the intake pipe pressure PM
is close to the steady running range pressure PMR/L, which is determined depending on the vehicle speed, and the negative pressure change amount △PM is determined by the negative pressure change amount judgment (
Direct PMB coming groove, and basic fuel injection time change amount △TP
When M is less than the acceleration judgment value TPB, only the minimum amount of fuel necessary for steady vehicle running is supplied by prohibiting non-uniform injection and setting the acceleration increase coefficient KACC to 1.0, so that the intake pipe pressure Even when PM changes, it is possible to avoid an excessive acceleration increase in the supply to the engine 2, which is substantially operated in a deceleration region, and improve fuel consumption efficiency.

In addition, in the deceleration region on the lower pressure side than the deceleration region judgment pressure PMI,
Normal non-uniform injection is performed only when the negative pressure change amount ΔPM is larger than the negative pressure change amount judgment value PMA, and the deceleration area judgment pressure P
In the deceleration region near a steady load on the higher pressure side than MI, during sudden acceleration where the negative pressure change amount ΔPM is greater than the negative pressure change amount determination value PMB, less co-current injection is performed than the above-mentioned normal non-concurrent injection. Therefore, by preventing the air-fuel ratio from shifting to the lean side (L e a n ), emission characteristics and drivability can be suitably maintained. Furthermore, since the asynchronous injection amount is proportional to the load change amount ΔPM and the load PM, it is possible to prevent the increase correction power from decreasing due to the fuel atomization state or the adhesion of fuel droplets to the wall surface. In addition, constant pressure PM2 for each acceleration increase area
In a more negative overload, the acceleration amount is increased using a small acceleration increase correction coefficient KACC only when in a state of rapid acceleration.On the other hand, in a more positive overload than constant pressure by acceleration increase range [)M2, when in a state of slow acceleration, the acceleration amount is increased. Instead, the acceleration amount is increased using a large acceleration amount correction coefficient KACC when the vehicle is in a rapid acceleration state. Therefore, unnecessary increase correction can be avoided. Therefore, since the operating range can be subdivided and an appropriate amount of fuel can be supplied to each operating range, the accuracy of fuel injection control is improved, and the air-fuel ratio is controlled on the lean side (Ri ch) and on the lean side (Lean). Large fluctuations can be prevented, and the amount of harmful components contained in exhaust gas discharged can be reduced.

Furthermore, the negative pressure change amount △PM in the deceleration region on the positive pressure side from the deceleration region determination pressure PMI (i P M
B is relatively large, and on the other hand, negative pressure change amount judgment of negative pressure change amount ΔPM in a region on the negative pressure side than deceleration region judgment pressure PMI (i P M A is set relatively smaller than the above negative pressure change amount judgment value PMB. Moreover, the asynchronous injection rJ′J
The amount is increased as the negative pressure change amount determination value becomes smaller and as the intake pipe pressure PM approaches the positive pressure side. In addition, the acceleration determination of the basic fuel injection time change amount ΔTPM in a region on the negative pressure side from the constant pressure PM2 for each acceleration increase region (fa T P B is relatively large, while the The acceleration judgment first shift TPA of the basic fuel injection time change amount △TPM is set to be relatively smaller than the acceleration judgment value TPB, and the acceleration increase coefficient K A CC increases as the acceleration judgment value decreases. Amount of change ΔT
The larger the PM, the more it increases. In this way, the acceleration increase is determined by load proportionality. Therefore, the amount of asynchronous injection in the deceleration region is relatively small and the acceleration increase coefficient is relatively small, while the amount of asynchronous injection in the deceleration region and acceleration region where acceleration is required is relatively large and the acceleration increase coefficient is relatively small. Since these values are determined individually, it is possible to prevent a decrease in responsiveness during acceleration and to suppress torque shock when accelerating from a small throttle valve opening, thereby achieving comfortable drivability for the occupants.

In this example, the deceleration region determination pressure P shown in FIG.
According to a map that defines the relationship between MI and constant pressure PM2 for each acceleration increase region and vehicle speed V, it was determined whether acceleration increase such as non-synchronized injection or acceleration increase synchronous injection is necessary. However, as shown in FIG. 8, for example, acceleration increases such as asynchronous injection and acceleration increase synchronous injection are performed according to a map that defines the relationship between the deceleration region determination opening TAI, the acceleration increase region determination opening TA2, and the vehicle speed V. It can also be configured to determine whether or not it is necessary. When configured in this way, the necessity of acceleration increase is determined by
If the determination is made based on the throttle valve opening TA detected by the throttle position sensor 22, the steady driving range opening TAR/L, the deceleration range determination opening TAI, and the acceleration increase range determination opening TA2, the result will be the same as in the above embodiment. It has a great effect.

Further, in this embodiment, the acceleration state is determined based on the value of the intake pipe pressure PM and the amount of change thereof, but it is also configured so that the determination is made based on the load determined from the intake air amount and rotational speed, for example. It's okay.

Furthermore, the steady running load may be determined from the vehicle speed and the gear position determined from the vehicle speed and rotational speed.

Although the embodiments of the present invention have been described above, the present invention is not equally limited to these embodiments, and it goes without saying that it can be implemented in various forms without departing from the gist of the present invention. .

Stand still! As described above in detail, the fuel injection amount control device for an internal combustion engine of the present invention increases acceleration when the load is included in the region near the steady load determined according to the vehicle speed and the requested acceleration state is a slow acceleration state. The acceleration increase supply amount is limited by either stopping the supply amount asynchronously, or by synchronously supplying the corrected acceleration increase supply amount by reducing the acceleration increase supply amount. It is configured to prevent oversupply of fuel. For this reason, the supplied fuel is limited to an amount suitable for realizing the required acceleration state, so even when the load or throttle valve opening increases, the internal combustion engine is effectively operated in the deceleration region. This has the excellent effect of not supplying more fuel than necessary and greatly improving fuel consumption efficiency.

In addition, in a steady load area determined corresponding to each vehicle speed, and in a state of slow acceleration, supply of non-same tunes is prohibited, or supply of a corrected acceleration increase supply amount by reducing the acceleration increase supply amount is prohibited. , do at least one of them. Therefore, optimal fuel can be supplied even during slow acceleration in the steady load region, preventing disturbances in the air-fuel ratio from the target air-fuel ratio, such as the air-fuel ratio shifting to the rich side or lean side. , deterioration of exhaust characteristics can be prevented.

Furthermore, in operating conditions where the throttle valve opening is small,
Since the acceleration increase supply amount does not change greatly, sudden fluctuations in output do not occur, and the occurrence of acceleration shocks that are uncomfortable for the occupants can be suppressed.

[Brief explanation of the drawing]

Fig. 1 is a basic configuration diagram conceptually illustrating the content of the present invention, Fig. 2 is a system configuration diagram of an embodiment of the present invention, Fig. 3 is a flowchart showing its control, and Fig. 4 is the same. A graph showing the map, FIG. 5 is a flowchart showing the control, FIG. 6 is a graph showing the map, and FIG. 7 is a flowchart showing the control.
FIG. 8 is a graph showing a map of another embodiment. Ml... Internal combustion engine M2... Operating state detection means M3... Fuel supply means M4... Control means M5,... Vehicle speed detection means M6... Calculation means Ml... Load determination means M8. ... Requested acceleration state determination means M9 ... Limiting means 1 ... Engine control device 2 ... Engine 3 ... Electronic control unit (ECU) 3a ... CPU 11 ... Fuel injection valve 22 ...・ Throttle position sensor 24 ・・
- Intake pipe pressure sensor 28...Rotation angle sensor 30...Vehicle speed sensor

Claims (1)

[Scope of Claims] 1. Operating state detection means for detecting the operating state of the internal combustion engine, including at least the required acceleration state, and fuel supply means for supplying the internal combustion engine with fuel according to an externally commanded supply amount. and determining an increased acceleration supply amount that is increased in accordance with the requested acceleration state detected by the operating state detection means, and increases the acceleration increase supply amount asynchronously or synchronously with the rotation of the internal combustion engine. A fuel injection amount control device for an internal combustion engine, comprising: a control means for instructing a fuel supply means; and a vehicle speed detection means for detecting a traveling speed of a vehicle driven by the internal combustion engine; calculation means for calculating a near-steady load region which is a load slight fluctuation region near a steady running load of the internal combustion engine, which is determined according to a vehicle speed determined according to the vehicle speed; A load determining means for determining whether or not the load is included in the calculated steady load vicinity area, and a load determining means for determining whether the required acceleration state detected by the operating state detecting means is a slow acceleration required state that is less than or equal to a predetermined acceleration state. The requested acceleration state determining means and the load determining means determine that the load of the internal combustion engine detected by the operating state detecting means is included in the region near the steady load, and the required acceleration state determining means When it is determined that the requested acceleration state detected by the driving state detection means is the slow acceleration requested state,
prohibition of a command to asynchronously supply the increased acceleration supply amount, or a restriction that instructs the control means to issue at least one of a command to synchronously supply a corrected acceleration increased supply amount that is reduced by correcting the increased acceleration supply amount; A fuel injection amount control device for an internal combustion engine, comprising: means.