JPS6282247A - Air-fuel ratio controller for internal combustion engine - Google Patents

Abstract

PURPOSE:To keep off an air-fuel ratio variation immediately after the occurrence of a load variation, by increasing the compensation value based on a difference between the specified time fundamental quantity and the delay operating value at a time when a difference between the fuel feed fundamental quantity and the responsive delay operating value comes to the specified value at the load variation. CONSTITUTION:An air quantity to be inhaled in an internal combustion engine M1 and an engine speed, or the detected value out of a load detecting M2 detecting load from throttle valve opening are all inputted into a control device M3 consisting of a microcomputer. A compensation device M4 predicts a fuel quantity to be stuck to a suction pipe wall surface of a suction port wall or a suction valve or the like on the basis of a load state, and calculates the responsiveness delay operating value. In addition, the compensation device M4, when a difference between the fuel feed fundamental quantity and the responsiveness delay operating value comes to more than the specified value, increases the compensation value extending over the specified time from that time.

Description

DETAILED DESCRIPTION OF THE INVENTION Object of the Invention [Field of Industrial Application] The present invention relates to an air-fuel ratio control device for an internal combustion engine, and more particularly to an air-fuel ratio control device for an internal combustion engine that is effective during load fluctuations of the internal combustion engine.

[Prior Art] When load fluctuations occur in an internal combustion engine, for example, when acceleration or deceleration is performed, control is performed for the purpose of compensating for fluctuations in the air-fuel ratio of the air-fuel mixture that contributes to combustion in the internal combustion engine. An air-fuel ratio control device for an internal combustion engine has been developed. For example, by predicting the amount of fuel that will adhere to the intake pipe wall surface such as the intake boat wall or intake valve based on information indicating the load state and warm-up state of the engine, and correcting the amount of supplied fuel accordingly. , [Air-fuel ratio control method and device] (Japanese Patent Application Laid-Open No. 57-24426@) has been proposed, which satisfactorily compensates for fluctuations in the air-fuel ratio of the air-fuel mixture that contributes to direct combustion in this engine.

[Problems to be Solved by the Invention] The conventional control device for an internal combustion engine has the following problems. That is, (1) When a load fluctuation of the internal combustion engine occurs, for example, an acceleration state or a deceleration state, the air-fuel ratio of the internal combustion engine changes significantly compared to the air-fuel ratio in a steady operating state. Conventionally, changes in the air-fuel ratio have been corrected based on, for example, a differential value of an intake pipe internal pressure sensor auxiliary output signal representing load fluctuations. However,
When the above-mentioned load fluctuation occurs, the air-fuel ratio exhibits a characteristic in which it changes significantly immediately after the load fluctuation occurs, and then gradually returns to its original value. For this reason, there is a problem in that it is not possible to quickly make a sufficient correction for a large change in the air-fuel ratio immediately after the load fluctuation occurs.

(2) Also, due to the problem in (1) above, immediately after a load change occurs, there is a delay in the air-fuel ratio correction.
Since the air-fuel ratio deviates greatly from the stoichiometric air-fuel ratio, there is also the problem that exhaust characteristics deteriorate.

An object of the present invention is to provide an air-fuel ratio control device for an internal combustion engine that appropriately controls the air-fuel ratio immediately after a load change occurs in the internal combustion engine.

Configuration of the Invention [Means for Solving the Problems] In order to solve the above problems, the present invention adopts the configuration shown in FIG. 1. FIG. 1 is a basic configuration diagram showing the content of the present invention. As shown in FIG. 1, the present invention includes a load detection means M2 that detects the load of the internal combustion engine M1, and a basic amount of fuel to be supplied to the internal combustion engine M1 according to the detected load. In the air-fuel ratio control device for an internal combustion engine, the air-fuel ratio control device for an internal combustion engine is further provided with a control means M3 that adjusts and controls the -F basic quantity with a correction amount according to the difference between the basic quantity and its response delay processing value. The means M3 is configured to include a correction means M4 that increases the correction amount for a predetermined time from then on when the difference between the basic 11 and its response delay processing value becomes a predetermined value or more. The gist of this paper is an air-fuel ratio control device for an internal combustion engine.

The load detection means M2 detects the load of the internal combustion engine M1. For example, the pressure sensor may be configured to detect the pressure inside the intake pipe of the internal combustion engine M1. Also,
The load on the internal combustion engine M1 may be detected based on the calculated value of the basic fuel injection load to the internal combustion engine M1. Furthermore, the intake air flow of the internal combustion engine M1 may be detected by an air flow meter, and the load may be detected from the intake air amount and the rotational speed of the internal combustion engine M1. Alternatively, the load may be detected from the throttle valve opening degree of the internal combustion engine M1.

The control means M3 calculates the basic fuel supply amount based on the load detected by the load detection means M2, and
This is necessary because control is performed to increase or decrease the basic fuel supply amount in accordance with the relationship between the basic fuel supply amount and its responsiveness delay processing value. For example, the basic fuel injection amount is calculated by dividing the intake air distance of the internal combustion engine M1 by the rotational speed and multiplying by a constant, and the basic fuel rA5 is calculated based on the intake air temperature of the internal combustion engine M1, the cooling water temperature, the throttle It is also possible to calculate the fuel injection range by correcting it based on values such as the valve opening degree. Note that the responsiveness delay processing value may be, for example, a weighted average value of past basic quantities, or may be, for example, an integral value of past basic quantities. Furthermore, various calculated values can be used, such as a value calculated from the basic quantity by a filter function having a predetermined delay constant.

The correction means M4 is a correction unit that corrects the basic amount for a predetermined time from that time when the difference between the basic amount of fuel supplied to the internal combustion engine M1 and its responsiveness delay processing value becomes a predetermined value or more. It increases the amount. For example, if the difference between the above-mentioned basic quantity and its responsiveness delay processing value is calculated, and it is determined from the calculated value that a load fluctuation of the internal combustion engine M1 has occurred, the above-mentioned calculated value will be changed to a specified value for a predetermined number of times from that time. The basic amount may be corrected by multiplying the calculated value by a constant.

The control means M3 and the correction means M4 can also be realized as independent discrete logic circuits.

In addition to the well-known CPU, ROM.

It is configured as a logic operation circuit from RAM and other peripheral circuit elements, and can realize both of the above means according to a predetermined processing procedure, and can also control and correct the fuel supplied to the internal combustion engine M1.

[Operation] As shown in FIG. 1, the air-fuel ratio control device for an internal combustion engine according to the present invention has
The control means M3 calculates the basic amount of fuel according to the load of the fuel, and further corrects the basic amount with a correction amount according to the difference between the basic amount and the response delay processing value.
When the difference between the basic amount and its responsiveness delay processing value exceeds a predetermined value, the correction amount is increased for a predetermined period of time from that time.

That is, when the load fluctuation of the internal combustion engine M1 occurs, the correction means M4 increases the correction amount for correcting the basic amount of fuel for a predetermined period of time from that time, so that the correction control of the basic m performed by the control means M3 is performed immediately. It will be executed.

Therefore, the air-fuel ratio control device for an internal combustion engine of the present invention works to quickly correct the amount of fuel supplied to the load fluctuation generating section 1 of the internal combustion engine M1. The technical problems of the present invention are solved by each component of the present invention acting as described above.

[Example] Next, a preferred example of the present invention will be described in detail based on the drawings.

An engine air-fuel ratio control device according to an embodiment of the present invention is as follows:
The system configuration is as shown in Figure 2.

As shown in FIG. 2, the engine 1 has a combustion chamber 5 formed by a cylinder 2, a piston 3, and a cylinder head 4.
A spark plug 6 is disposed in the combustion chamber 5.

The intake system of the engine 1 includes an intake valve 7 in the combustion chamber 5.
An intake manifold 8 that communicates with the intake manifold 8, a fuel injection valve 9 that injects fuel into the intake manifold 8, an intake pipe 10 that communicates with the intake manifold 8, a surge tank 11 that absorbs pulsation of intake air, a throttle valve 12, and an air cleaner. It is composed of 13h1 and others. Further, the exhaust system of the engine 1 includes an exhaust manifold 15 that communicates with the above-mentioned combustion chamber 5 via an exhaust valve 14. Furthermore, the engine 1 includes an igniter 16 that outputs the high voltage necessary for ignition, and a distributor 17 that is linked to a crankshaft (not shown) and distributes the high voltage generated by the igniter 16 to the spark plugs 6 of each cylinder. .

The engine 1 includes a water temperature sensor 20 provided in the cooling system of the engine 1 to detect the temperature of the cooling water, an intake temperature sensor 21 provided in the air cleaner 13 to detect the temperature of the intake air sent to the engine 1, and a throat 1 - a throttle position sensor 22 that detects the opening degree of the throttle valve 12 in conjunction with the throttle valve 12; an intake pipe pressure sensor 23 that communicates with the intake pipe 10 and measures the pressure inside the intake pipe;
, an oxygen concentration sensor 24 that is installed in the exhaust manifold 15 and detects the residual oxygen concentration in the exhaust gas as an analog signal; and an oxygen concentration sensor 24 that is installed in the distributor 17 and detects the residual oxygen concentration in the exhaust gas as an analog signal; A rotation angle sensor 25, which also serves as a rotation speed sensor, outputs a rotation angle signal every integer multiple of 0° to 30', every 1 revolution of the camshaft of the distributor 17, that is, every 2 revolutions of the crankshaft (not shown). Each cylinder is provided with a cylinder discrimination sensor 26 that outputs a reference signal once.

The signals detected by the above-mentioned sensors are input to an electronic control unit (hereinafter simply referred to as ECU) 30, and the ECU 3O drives the fuel injection valve 9 and igniter 16 described above based on each signal to control the engine 1. control.

Next, the configuration of the ECU 3O will be explained based on FIG. 3. ECU 3O inputs and calculates each signal detected by each sensor mentioned above according to a control program, and also performs processing for controlling each device mentioned above.
The PU 30a, the ROM 30b in which the above control program and initial data are stored in advance, the RAM 30G in which various signals input to the ECU 3O and data necessary for calculation control are temporarily stored, and the engine 1 key switch is turned off by the driver. It is configured as a logic operation circuit centered around a backup RAM 306 backed up by a battery so that it can store and hold various data necessary for controlling the engine 1 from now on. 30 (7, connected to output port 30H to perform input/output with external equipment.

The ECtJ30 includes the intake pipe pressure sensor 23 described above,
A buffer 30 for output signals from the water temperature sensor 20, intake temperature sensor 21, and throttle position sensor 22! ,
A multiplexer 30n1 that selectively outputs the output signals of the above-mentioned sensors to the CPU 30a and an A/D converter 30p that converts analog signals into digital signals are also provided. . Each of these signals is sent to the CPU 30 via the input/output port 30f.
input to a. The ECU 3O also includes a buffer 30Q for the output signal of the oxygen concentration sensor 24 described above, a comparator 30r that outputs a signal when the output voltage of the buffer 30q exceeds a predetermined voltage, the cylinder discrimination sensor 26 described above, and the rotation It has a waveform shaping circuit 30S that shapes the waveform of the output signal of the angle sensor 25. Each of these signals is input to the CPU 30a via the input port 30Q. Further, the ECU 3O includes a drive circuit 30t that supplies a drive current to the fuel injection valve 9 and the igniter 16 described above.

30u, and the CPU 30a outputs a control signal to both drive circuits 30t and 30U via an output port 30h. In addition, ECLJ30 includes CPU30a and ROM30.
b, a clock circuit 30 that sends a clock signal serving as control timing to the RAM 30c and the like at predetermined intervals.

Next, the fuel injection correction coefficient calculation process executed by the ECU 3O will be explained based on the flowchart shown in FIG. 4. This process is performed at the crank angle 36 of the engine 1.
00, and is repeatedly executed in synchronization with the rotation of the engine 1. Note that before starting this process, a basic fuel injection time TP8 (not shown) is calculated based on the intake pipe pressure detected by the intake pipe pressure sensor 23 of the engine 1 and the rotation speed detected by the rotation angle sensor 25. Fuel injection time calculation processing is performed in advance.

In this process, a fuel injection correction coefficient is calculated based on this basic fuel injection time TP.

First, in step 100, the difference DT between the basic fuel injection time TP and its previously calculated weighted average value TPMi-1
A process is performed to calculate P as shown in the following equation (1).

DTP=TP-TPMi-1 (1) In the following step 102, it is determined whether the difference DTP calculated in step 100 is positive. If the difference DTP is positive, the process advances to step 104. On the other hand, if the difference DTP is not positive, the process proceeds to step 144. Here, the following explanation will be given for the case where the difference DTP is positive. Step 1
04, the constant M (128 in this example) is calculated from the above difference DTP.
A process of subtracting [μ5ecl) is performed. In the following step 106, it is determined whether the difference DTP subtracted by the constant M in step 104 is negative. Here, if the difference DTP is greater than or equal to the constant M, the calculated value is positive, it is determined that the engine 1 is in an accelerating state, and the process proceeds to step 108.

In step 108, processing is performed to calculate the acceleration increase coefficient m FAEWTP as shown in the following equation (2).

FAEWTP=DTPXα1 (2) where α1 is a constant and the difference DTP has a time dimension.
is converted into a dimensionless number of an appropriate value.

In the subsequent step 110, it is determined whether the value of the counter C0UNT is less than a constant A (2 to 5 [times] in this embodiment). Here, the constant A has a characteristic that its value increases as the cooling water temperature THW decreases, as shown by the solid line in FIG. The ECU 3O previously stores a map as shown in FIG. 5 in a predetermined area in the ROM 30b, and selects and uses the value of A corresponding to the cooling water temperature THW at that time. If the count of the counter C0UNT is insufficient and is less than the constant A, the process proceeds to step 112. Here, the value of the acceleration increase coefficient FAEWTP or the deceleration decrease coefficient DDW described later is set to a constant β1 (in this example, 4
) is used to form the following equation (3).

Amplification processing as shown in (4) is performed.

FAEWTP=FAEWTPxβ1...(3)D
DW = DDW Next, the process proceeds to step 114, where a process of adding 1 to the value of the counter C0LINT is performed.

In the subsequent step 116, a process is performed to calculate a weighted average value TPMi of the basic fuel injection time as shown in the following equation (5).

TPMi = ((x-1)XTPMi-1+TP)/x
...(5) However, X is a constant T PM i-1 is a weighted average value of the basic fuel injection time calculated last time.

As shown in FIG. 6, the constant X is the cooling water temperature TI-IW.
It has a characteristic that as the value decreases, its value increases. The ECU3O stores a map as shown in Figure 6 in advance in the ROM.
The value of X corresponding to the cooling water temperature THW at that time is selected and used. After that, the process goes to NEXT and ends this process.

On the other hand, when this process is repeated several times and the value of the counter C0UNT becomes equal to or greater than the constant A, the process proceeds from step 110 to step 120. In step 120, the counter C0
It is determined whether the value of UNT is less than a constant B (4 to 10 [times] in this embodiment). Here, the constant B is
As shown by the broken line in FIG. 5, the cooling water temperature T I-I W
It has a characteristic that as the value decreases, its value increases. The ECU3O has prepared a map as shown in Fig. 5 in advance.
It is stored in a predetermined area in M30b, and the value of B corresponding to the cooling water temperature THW at that time is selected and used.

If the count of the counter C0UNT is insufficient and less than the constant 8, the process proceeds to step 122. Here, the acceleration mitral coefficient FAEWTP described above or the deceleration reduction coefficient DDW described later is used.
The value of is calculated using the constant β2 (2 in this example) by the following equation (6
), (7) amplification processing is performed.

FAFW block P=FAEW block 1) x β2...(6)
DDW=DDWXβ2...(7
) Immediately after the engine 1 shifts to the acceleration state or deceleration state, the amplification is performed for a predetermined time in step 112, but even after that, the coefficient is further increased for a predetermined time to quickly amplify the amplification. This is a process executed to perform correction. Next, step 114 described above,
The process proceeds to step 116 and ends this process.

This process is repeated several times, and when the value of the counter C0UNT becomes equal to or greater than the constant B, the process advances from step 120 to steps 114 and 116, exits to NEXT, and ends the process.

On the other hand, if it is determined in step 106 that the difference DTP subtracted by the constant M is negative, it is assumed that the engine 1 is in a steady operating state, and the process proceeds to step 130. In step 130, processing to set the difference DTP to O is performed.

In the following step 132, a process is performed to reset the counter C0UNT to the value O, and then the process proceeds to NEXT via the previously described step 116, and the present process ends.

Further, if it is determined in step 102 that the difference DTP is not positive, the process proceeds to step 144. Step 1
44, the above difference DTP is set to a constant M (in this embodiment, 128[
[μsec]) is added. In the following step 146, it is determined whether the difference DTP added by the constant M is positive or not. Here, if the absolute value of the difference DTP is greater than or equal to the constant M, the output value will be negative,
It is determined that the engine 1 is in a deceleration state, and the process proceeds to step 148. In step 148, the deceleration reduction coefficient D
A process of calculating DW as shown in the following equation (8) is performed.

DDM=DTPxc<2...(8
) However, α2 is a constant, and the difference D having the dimension of time
It converts TP into a dimensionless number with an appropriate value.

Thereafter, the process proceeds to step 110 described above, where amplification and correction of the deceleration color reduction coefficient DDW, etc. are performed, and the process exits to NEXT to end the present process.

On the other hand, if it is determined in step 146 that the difference DTP added by the constant M is positive, the engine 1 is considered to be in a steady operating state, and step 1
Go to 50. In step 150, processing to set the difference DTP to O is performed. In the following step 152, the counter C
A process of resetting 0UNT to 1O is performed, and then the process proceeds to NEXT via step 116 described above, and the process ends.

The acceleration increase coefficient FAEWTP or deceleration decrease coefficient DDW calculated in this process is used to correct the basic fuel injection time TP in an actual fuel injection time calculation process (not shown).

2) This fuel injection correction coefficient extraction process is repeatedly executed at every crank angle of 3600 in synchronization with the rotation of the engine 1.

Next, as an example of the above-mentioned control, a description will be given based on a timing chart shown in FIG. 7, which expresses changes in various quantities over time when deceleration and reduction are performed.

At time t1, engine 1 shifts to a deceleration state.

Therefore, the basic fuel injection time TP starts to decrease rapidly from the same time t1. On the other hand, the weighted average value TPM is
The fuel injection correction coefficient decreases in stages each time it is calculated by the calculation algorithm. Therefore, the difference DTP between the basic fuel injection time TP and its weighted average value TPM takes a negative value,
Moreover, its absolute value is greater than 128 [μsec].

Therefore, from time t1, the deceleration reduction coefficient DDW is calculated as shown by the broken line in the figure, and furthermore, the counter C0UNT
Since the value of is O, which is less than the constant A (2 in this case), the deceleration reduction coefficient DDW is multiplied by β1 (4 in this case) and becomes a large value as shown by the solid line in the figure. Counter C0UN
From time t2 when the value of T is 2 and becomes greater than or equal to the constant A, the deceleration reduction coefficient DDW is multiplied by β2 (2 in this case) and amplified to a value as shown by the solid line in the figure. Therefore, the actual fuel injection time is quickly shortened. From time t3 when the value of the counter C0UNT becomes 5, which is greater than or equal to the constant B (5 in this case), the deceleration reduction coefficient DDW is no longer amplified. Hereinafter, the basic fuel injection time TP and its weighted average value TPM
Since the difference DTP decreases, the deceleration reduction coefficient DDW
The value of also decreases. At time t4, the difference DTP between the basic fuel injection time TP and its weighted average value TPM is 128.
[μsec] or less, the deceleration reduction coefficient DDW is O
becomes. Note that the deceleration state continues until time t5, after which the vehicle shifts to a steady running state. As described above, from time t1 to time t3 immediately after the engine 1 shifts to the deceleration state, if the deceleration reduction coefficient DDW is not amplified as in the conventional case, the air-fuel ratio will be lower than the stoichiometric air-fuel ratio as shown by the broken line in FIG. It will be far away from the dark side (Rich). However, in the case of this embodiment, between time t1 and time t2, the deceleration reduction coefficient DD
W is amplified by β1 times, and the deceleration reduction coefficient DDW is amplified by β2 times from time t2 to time t3, so from time t1 to time t3, the air-fuel ratio is as shown by the solid line in the figure. It moves away from the stoichiometric air-fuel ratio to the rich side (Rich>), but
They do not deviate greatly, and improvements have been made to reduce the extent to which they deviate.

On the other hand, when the engine 1 shifts to an acceleration state, similarly, the acceleration increase coefficient FAEWTP is amplified immediately after the transition to the acceleration state, and the actual fuel injection time is immediately extended, so that the air-fuel ratio is thinner than the stoichiometric air-fuel ratio. However, the amount of separation is improved to be smaller.

Note that in this embodiment, the engine 1 is replaced by the internal combustion engine M1,
Intake pipe pressure sensor 23, rotation angle sensor 25, and ECU
3O is the load detection means M2, and the ECU 3O is the control means M
Each of these applies to 3. Also, the ECU 3O and the processes executed by the ECU 3O (steps 100, 102, 104)
, 106, 108. 110, 112, 114. ．． 116
, 120°122.144, 146.148> functions as the correction means M4.

As explained above, in this embodiment, when the engine 1 shifts to an acceleration state or a deceleration state, the basic fuel injection time T
The difference DTP between P and its weighted average value TPM is 128[
μsec] or more, first the predetermined number of times A (2 to
Within 5 [times]), the acceleration increase coefficient FAEW DingP or the deceleration decrease coefficient DDW is multiplied by β] (4 in this example),
Next, both of the coefficients are multiplied by β2 (2 in this embodiment) within a predetermined number of times B (4 to 10 [times]). Therefore, immediately after the engine 1 shifts to an acceleration state or a deceleration state, the acceleration increase coefficient FAEWTP or the deceleration decrease coefficient r&DDW is set to a large value, so that the actual fuel injection time is promptly extended or shortened. Therefore, it is possible to prevent a phenomenon in which the air-fuel ratio deviates significantly from the stoichiometric air-fuel ratio immediately after the engine 1 shifts to an acceleration state or a deceleration state.

Moreover, with the above effect, the air-fuel ratio can be controlled to be close to the U-scheme air-fuel ratio even immediately after the engine 1 shifts to the acceleration state or deceleration state, so that the generation of harmful components in the exhaust gas can be prevented.

Furthermore, when amplifying the acceleration increase coefficient r&FAEWTP or the deceleration decrease coefficient DDW, the cooling water temperature T I
- Constants A and B determined based on IW are set, and corrections from the first correction to constant A are performed using constant β1 (in this example,
), and in the subsequent correction up to the constant B, the constant β2 (2 in this embodiment) performs a smaller amplification than the initial one.

Therefore, with a relatively small amount of amplification correction, it is possible to minimize sudden changes in the air-fuel ratio immediately after the engine 1 shifts to an acceleration state or a deceleration state, and to quickly correct subsequent changes in the air-fuel ratio. Become.

In addition, since the constant X used to calculate the weighted average value of the basic fuel injection time TP is set based on the cooling water temperature - IW, There is also the advantage that transition to an acceleration state or a deceleration state can be detected quickly.

In this example, transition of the engine 1 to an acceleration state or a deceleration state was determined based on the basic fuel injection time TP. However, the effects of the present invention can also be achieved even if the determination is made based on the change in the intake pipe pressure output from the intake pipe pressure sensor, for example.

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 the present invention can be implemented in various forms without departing from the gist of the present invention. .

Effects of the Invention As detailed above, in the internal combustion engine control device of the present invention, the control means calculates the basic amount of fuel to be supplied to the internal combustion engine based on the load detected by the load detection means, and
When performing control to adjust the basic amount with a correction amount according to the difference between the basic amount and its responsiveness delay processing value, the correction means determines that the difference between the basic amount and its responsiveness delay processing value is greater than or equal to a predetermined value. When this occurs, the correction amount is increased over a predetermined period of time from that time. Therefore, an excellent effect is achieved in that a large change in the air-fuel ratio that occurs immediately after a load change occurs in the internal combustion engine can be quickly corrected.

Moreover, since large changes in the air-fuel ratio are suppressed even immediately after load fluctuations occur in the internal combustion engine, it is possible to control the air-fuel ratio to maintain good exhaust characteristics.

[Brief explanation of drawings]

Fig. 1 is a basic configuration diagram showing the contents of the present invention, Fig. 2 is a system configuration diagram of an engine air-fuel ratio control device which is an embodiment of the present invention, and Fig. 3 is the same electronic control unit (ECU).
FIG. 4 is a flowchart 1 to 1 showing the processing executed by the ECU in one embodiment of the present invention, and FIG. 5 is a block diagram for explaining the configuration of
Fig. 6 is a graph showing a map specifying the relationship between constant X and cooling water temperature THW, Fig. 7 is a graph showing a map specifying the relationship between constant A timing chart expressing v- over time
It's 1~. Ml... Internal combustion engine M2... Load detection means M3... Control means M4... Correction means 1... Engine 20... Water temperature sensor 22... Throttle position sensor 23... Intake pipe pressure Sensor 25...Rotation angle sensor

Claims (1)

[Scope of Claims] 1. Load detection means for detecting the load of an internal combustion engine, calculating a basic amount of fuel to be supplied to the internal combustion engine according to the detected load, and calculating the basic amount and its responsiveness. In an air-fuel ratio control device for an internal combustion engine, the control means controls the basic quantity by adjusting it by a correction amount according to the difference from the delayed processing value, further comprising: An air-fuel ratio control device for an internal combustion engine, comprising a correction means for increasing the correction amount for a predetermined period of time from that time when a difference from a delayed processing value becomes equal to or greater than a predetermined value.