JPS61237851A - Supply device of fuel to internal-combustion engine - Google Patents

Abstract

PURPOSE:To smoothly perform acceleration and deceleration in no relation to an aged deterioration or the like, by constituting an engine such that an acceleration and deceleration correction quantity is study controlled, in the case of the engine which corrects, when it is accelerated and decelerated, a fuel injection quantity on the basis of the acceleration and deceleration correction quantity stored in a memory means. CONSTITUTION:The first correction coefficient calculating means 3 calculates an air-fuel ratio correction coefficient on the basis of an output signal from an O2 sensor 2. While a decision means 4 decides whether or not an internal-combustion engine 1 is in the change required time of its speed, and on the basis of this decision result and an acceleration and deceleration correction amount stored in a memory means 5, the second correction coefficient calculating means 6 calculates an acceleration and deceleration correction coefficient. And on the basis of said both correction coefficients and the basic injection quantity, an injection quantity calculating means 7, calculating an injection quantity of fuel, controls an injection means 8. Here on the basis of an output signal of the O2 sensor after a predetermined time from that the decision means 4 decides the engine in the change required time of its speed, a change means 9 changes the acceleration and deceleration correction quantity stored in the memory means 5.

Description

[Detailed Description of the Invention] [Summary] When increasing or decreasing the rotation speed of an internal combustion engine, conventionally, the fuel injection amount is corrected based on an acceleration/deceleration correction amount (fixed value) stored in a storage means. However, the present invention has a configuration in which the acceleration/deceleration correction amount is controlled by learning, so that acceleration and deceleration can be performed smoothly even when the characteristics of the internal combustion (current engine) change due to aging etc. do.

[Industrial application field]

The present invention relates to an improvement in a fuel supply system for an internal combustion engine, and more specifically, the present invention relates to an improvement in a fuel supply system for an internal combustion engine, and more specifically, the present invention relates to a fuel supply system for an internal combustion engine that can smoothly accelerate and decelerate even when the characteristics of the internal combustion engine change due to aging or the like. It is related to the device.

[Conventional technology]

Based on the detection results of the 02 sensor such as the zirconia 02 sensor that detects the oxygen concentration in the exhaust gas of the internal combustion engine, it is determined whether the air-fuel ratio A/F is in a rich state or a low state. It has been proposed in the past to perform air-fuel ratio feedback control based on the air-fuel ratio.

FIG. 6 is a diagram showing the relationship between the state of the air-fuel ratio A/F and the air-fuel ratio correction coefficient FAF. , decreases at a predetermined slope, and when the air-fuel ratio A/F becomes lean, after skiving a certain amount, increases at a predetermined slope.

Note that the reason why the air-fuel ratio correction coefficient FAF is skipped by a certain amount is to eliminate the influence of the response delay of the 02 sensor. By the way, the fuel injection quantum ^U is determined by multiplying the basic injection amount TP determined by the rotational speed of the internal combustion engine and the intake air amount by the air-fuel ratio correction coefficient FAF, and the air-fuel ratio correction coefficient PAP is determined by the air-fuel ratio correction coefficient FAF. Since the fuel ratio A/F decreases when it is in a rich state and increases when it is in a lean state, the amount of fuel determined by multiplying the basic injection amount TP and the air-fuel ratio correction coefficient PAP is injected. This makes it possible to bring the actual air-fuel ratio closer to the stoichiometric air-fuel ratio.

By performing this kind of air-fuel ratio feedback control, it is possible to bring the actual air-fuel ratio close to the stoichiometric air-fuel ratio in a steady state, but it is possible to bring the actual air-fuel ratio close to the stoichiometric air-fuel ratio in a steady state. In this case, the air-fuel ratio becomes far from the stoichiometric air-fuel ratio due to a delay in the response of the fuel supply system, resulting in a problem that smooth acceleration or deceleration cannot be performed. For example, suppose that the throttle opening is suddenly increased for acceleration at time t1 and suddenly decreased for deceleration at time t2, as shown in FIG. 7(A). The output signal of the 02 sensor, which outputs a signal corresponding to the oxygen concentration in the exhaust gas, is at a low level for a while after acceleration, and at a high level for a while after deceleration, as shown in Figure CB). In other words, when the throttle opening is suddenly increased for acceleration, there is a temporary excess of air and fuel shortage (lean state), and when the throttle opening is suddenly decreased for deceleration, there is a temporary shortage of air and fuel. Due to excess fuel (rich state), emissions 1 have a negative impact on drivability, making it difficult to accelerate smoothly,
There was a problem that deceleration could not be performed.

Therefore, in order to solve this problem, the fuel Jl TAU to be supplied to the internal combustion engine is determined by the following equation (1), and the acceleration/deceleration correction coefficient α is changed as shown in FIG. 7(C). It is also proposed that However, in the opening ceremony, TP is the basic injection amount determined from the rotational speed of the internal combustion engine and the amount of intake air, and FAP is the air-fuel ratio correction coefficient.

TAII = TPX FAF x cx ・--
−−−−−−(1) Here, the acceleration/deceleration correction coefficient α is as shown in the figure (
As can be seen from C), it is held at 1.0 in the non-acceleration/deceleration state, increases by the unit correction amount Δα during acceleration, and decreases by the unit correction amount Δα′ during deceleration. It is possible to prevent fuel shortage or excess fuel during deceleration, and to smoothly perform acceleration or deceleration. Furthermore, when acceleration or deceleration is completed, the acceleration/deceleration correction coefficient α returns to 1.0 with a predetermined slope. Note that (D) in the same figure shows the output signal of the 02 sensor when the amount of fuel determined by equation (1) is supplied to the internal combustion engine.

However, the conventional example described above also has the following problems.

That is, in the past, the unit correction amounts Δα and Δα' were set to fixed values, so if the characteristics of the internal combustion engine deteriorated due to aging, for example, or the unit correction amounts Δα and Δα' were set to an appropriate value for the internal combustion engine. Otherwise, there is a problem that acceleration or deceleration cannot be performed smoothly.

(Problems to be Solved by the Invention) The present invention solves the above-mentioned problems, and its purpose is to accelerate or decelerate even when the characteristics of the internal combustion engine deteriorate due to aging etc. The goal is to make it possible to do this in an efficient manner.

[Means for solving problems]

In order to solve the above-mentioned problems, the present invention, as shown in FIG. a first correction coefficient calculating means 3 that calculates an air-fuel ratio correction coefficient based on an output signal; (1) a determining means 4 that determines whether or not it is time to request a change in the rotational speed of the internal combustion engine l; and (4) an optional determining means. a second correction coefficient calculation means 6 that calculates an acceleration/deceleration correction coefficient based on the determination result of step 4 and the acceleration/deceleration correction amount stored in the storage means 5; and (1) the first calculation means 3.
an injection amount calculation means 7 that calculates the fuel injection amount to the internal combustion engine 1 based on the air-fuel ratio correction coefficient calculated by the second calculation means 6, the acceleration/deceleration correction coefficient calculated by the second calculation means 6, and the basic injection amount; In the fuel supply device for an internal combustion engine, which includes an injection means 8 for supplying an amount of fuel corresponding to the calculation result of the injection amount calculation means 7 to the internal combustion engine 1, and a changing means 9 for changing the acceleration/deceleration correction amount stored in the storage means 5 based on the output signal of the 02 sensor 2 after a predetermined period of time after it is determined that the rotational speed change is requested. A fuel supply device for an internal combustion engine, characterized by:

[For production]

Since the acceleration/deceleration correction amount is learning-controlled by the changing means 9, even if the characteristics of the internal combustion engine change due to aging or the like, acceleration/deceleration can be performed smoothly.

〔Example〕

FIG. 2 is a block diagram of an embodiment of the present invention, where 21 is a microprocessor, 22 is a ROM in which a control program etc. for causing the microprocessor 21 to perform predetermined operations is stored, and 23 is an acceleration/deceleration correction coefficient α. .

A RAM having a back amplifier power supply (not shown) in which unit correction amounts Δα, Δα゛, etc. are stored, 24 an input section, 2 an output section, 26 an internal combustion engine body, a nail an air cleaner, 4 an air flow meter, 29 30 is a throttle chamber, 30 is an intake manifold, 31 is a fuel injector, 32 is a throttle valve, 33 is an opening sensor that detects the opening of the throttle valve 32, 34 is a water temperature sensor that detects the cooling water temperature, and 35 is an exhaust gas. A sensor 02 outputs a signal corresponding to the oxygen concentration in the gas, an AD converter 36 and 37, and a crank angle sensor 38 outputs a position detection signal every time the crankshaft rotates by a certain angle.

3 to 5 are flowcharts 1-- showing part of the processing contents of the microprocessor 21, and the operation of FIG. 2 will be described below with reference to the same figures.

The microprocessor 21 performs the processing shown in the flowchart of FIG. 3 at predetermined time intervals during its processing flow. That is, the microprocessor 21 determines the opening degree θ of the throttle valve 32 based on the detection result of the opening degree sensor 33 which detects the opening degree of the throttle valve 32 at predetermined time intervals. (step S1), and then the difference Δθ=θ between the opening degree θn found in step S1 and the opening degree θn−1 found in step Sl of the previous cycle. -θn@ is determined (step S2), and then it is determined whether the difference Δθ satisfies Δθ>O (step 33). If the determination result in step S3 is VES, the absolute value 1Δθ1 of the difference Δθ is 1Δθ
Step S4 to determine whether lax is satisfied.
), or 1Δθ if the judgment result in step S3 is No.
1 satisfies the relationship 1Δθl>y (step 510).

That is, in step S4, it is determined whether the rate of change in the opening degree of the throttle valve 32 in the direction in which the throttle valve 32 is opened (hereinafter referred to as the rate of change in the child direction) is greater than or equal to a predetermined value. The rate of change in the opening degree of the throttle valve 32 in the direction of closing (hereinafter referred to as the rate of change in one direction)
This means that it is determined whether or not is greater than or equal to a predetermined value.

Then, if the determination result in step S4 is YES, that is, if it is determined that it is required to increase the rotational speed of the internal combustion engine, the microprocessor 21 uses the 02 sensor 35 to detect the ^D converter 37 and the input unit 24. It is determined whether the air-fuel ratio at that time is in a lean state based on the signal applied via the controller (step S5). If the determination result in step S5 is YES, the microprocessor 21 sets the flag F1 to "1" (step S6), then sets the count value CI of the internally provided counter CNTl to rOJ (step S7), Then RAM23
The value obtained by adding the unit correction amount Δα to the acceleration/deceleration correction coefficient α stored in the RAM
23 (step S8), and then the process moves to another control step S9. Also, the determination result in step S5 is No.
In this case, after performing the process of step S8, the process moves to another control step S9, and if the determination result of step S4 is NO, the process directly moves to another control step S9 without performing the process of steps 85 to 8. It is something.

Note that the counter CNTl is set for a predetermined time (for example, 10 m5e
The acceleration/deceleration correction coefficient α is determined by steps S57 to S60 of the flowchart shown in FIG. 5, which will be described later. In this case, it is held at 1.0. Therefore, when the opening degree of the throttle valve 32 suddenly increases, the acceleration/deceleration correction coefficient α is determined so that the rate of change in the opening degree of the throttle valve 32 in the child direction exceeds a predetermined value, as shown in FIG. 7(C). While , the unit correction amount Δα increases.

Further, if the determination result in step SIO is YES, that is, if it is determined that it is required to reduce the rotational speed of the internal combustion engine 26, the microprocessor 21
Based on the output signal of the second sensor 35, it is determined whether the air-fuel ratio at that time is in a rich state (step 5ll).

Then, if the judgment result in step Sll is YES,
The microprocessor 21 sets the flag F2 to "1" (step 312), and then sets the count value C1 of the internal counter CNTl to "0" (step 51).
3) Next, the value obtained by subtracting the unit correction amount Δα from the acceleration/deceleration correction coefficient α stored in the RAM 23 is stored in the RAM 23 as a new acceleration/deceleration correction coefficient α (step 51
4) After this, the process moves to another control step S9. Furthermore, if the judgment result in step 7 is No, step S1
After performing the process in step 4, the process moves to another control step S9.
If the judgment result of step SIO is No, step Sl
Directly perform other control steps S without performing processes 1 to 14.
9.

Therefore, when the opening degree of the throttle valve 32 suddenly decreases, as shown in FIG. 7(C), the acceleration/deceleration correction coefficient α
is decreased by the unit correction amount Δα' while the rate of change in the opening degree of the throttle valve 32 in one direction is greater than or equal to a predetermined value.

In addition, the microprocessor 2I also performs the process shown in the flowchart of FIG. 4 at predetermined time intervals in its process flow. That is, the microprocessor 21 sets the flag Fl.
When it is determined that is rlJ and that the air-fuel ratio at that time is in a rich state (step S21.22), flag F is
1 to "0" (step 523), and then the counter (
: It is determined whether the count value CI of NT1 is less than or equal to a predetermined value A (step 524). Here, counter CN
As mentioned above, Tl is incremented by the interrupt routine that occurs every 10 m5ec, and its count value C1 is set to "0" in step S7 or step 313 of the flowchart shown in FIG. Therefore, the count value C1 indicates the time from the processing of step S8 or step S14 to the present. However, the process shown in the flowchart in Figure 3 is 1
Since this is performed many times within sec, the example shown in FIG. 7 shows the time from time L3 or time t4 to the present. Further, the predetermined value A is set to a value corresponding to, for example, l sec.

If the determination result in step 324 is NO, that is, if it is determined that 1 sec or more has elapsed since the processing in step S8, the microprocessor 21 returns the count value C2 of the counter CNT2 provided therein. is set to "0" (step 525), and then RAM2
The value obtained by adding a predetermined value to the unit correction amount Δα stored in No. 3 is stored in the RAM 23 as a new unit correction amount Δα (step 326), and then the process of step S31 is performed. Further, if the determination result of step S24 is YES, that is, 1 se
If it is determined that c has not elapsed, counter CNT2
The count value C2 is incremented by +1 (step 527), and then it is determined whether the count value C2 satisfies the relationship 02≧lO (step 828).

Here, the count value C2 of the counter CNT2 is incremented by 1 (
Step 527), the time from performing the process in step S8 to performing the process in step 528 is 1 sec.
If it is, the count value C2 of the counter CNT2 indicates that the air-fuel ratio changes from a lean state to a rich state within 1 sec after performing the process of step S8, since it is set to rOJ (step 525). It shows how many times it happened in a row. If the determination result in step 82B is YES, that is, after performing the process in step S8, 1. The air-fuel ratio changes from a lean state to a rich state within 10 seconds consecutively.
If it continues more than once, the count value c of counter CNT2
2 to rO'' (step 529), then the RAM 23
The value obtained by subtracting the predetermined value (from the unit correction amount Δα stored in ) is stored in the RAM 23 as a new unit correction amount Δα (step 530), and then the process of step 531 is performed. Also, step S21.22.28 Even if the determination result is NO, the process of step S31 is performed.

Here, the processing of steps 321 to 30 will be explained with reference to FIG. 7 as follows. That is, from time t3 when the acceleration/deceleration correction coefficient α is increased and the fuel injection amount is increased,
If the air-fuel ratio does not change from the lean state to the rich state even after sec has elapsed (if the determination result in step S24 is NO), the unit correction amount Δα is determined to be small and processing is performed to increase it (step 826). Further, if the air-fuel ratio changes from a lean state to a rich state before I sec has elapsed from time t3 (the determination result of step S24 is
ES), 1 se after performing the process of step S8 based on the count value C2 of the counter CNT2
In step 528), it is determined whether or not the air-fuel ratio has changed from a lean state to a lean state continuously 10 times or more within c. (step 530).

Further, in step S31, it is determined whether the flag F2 is "1", and in step S32, it is determined whether the air-fuel ratio at that time is in a lean state. And flag F2
is "1" and the air-fuel ratio is at 1, the microprocessor 21 sets the flag F2 to "1".
0'' (step 533), then the counter CNTl
Whether or not the count value C1 satisfies the relationship C1<A, that is, after performing the process of step S14.
sec has elapsed (step 534).
). Then, if the determination result in step S34 is NO,
That is, 1 sec after performing the process of step S14.
If it is determined that the above period has elapsed, the microprocessor 2
1 sets the count value C3 of the counter CNT3 provided therein to "0" (step 535), and then R
A predetermined value t is set to the unit correction amount Δα° stored in AM23.
The added value is set as a new unit correction amount Δα° and stored in RAM.
23 (step 836), and performs the process of control step 341 for this removability. If the determination result in step S34 is ygs, that is, if it is determined that 1 sec has not elapsed since the processing in step Sl/I, the count value C3 of the counter CNT3 is increased by +1 (step 537), and then Count value C3 is C3≧10
Determine whether the relationship is satisfied (Step 5)
3B).

Here, the count value C3 of the counter CNT3 is incremented by 1 if the time from performing the process of step S14 to performing the process of step S34 is within 1 sec (step 537); The time required to process step 33B is 1 s.
If it is greater than or equal to ec, it will be set to "0" (
Step 535), count value C3 of counter CNT3
indicates how many times the air-fuel ratio continuously changes from a rich state to a lean state within 1 sec after the process of step S14 is performed. If the determination result in step 838 is YES, that is, if the air-fuel ratio changes from a rich state to a lean state continuously 10 times or more within 1 sec after performing the process in step 314, Set the count value C3 of the counter CNT3 to "0" (step 539), then R
The value obtained by subtracting the predetermined value t from the unit correction amount Δα° stored in AM23 is set as the new unit correction amount Δα゛ RA
It is stored in the M edict (step 540), and then the process moves to another control step S41. Also, step S31.32゜3
If the determination result in step 8 is NO, the process in step 341 is also performed.

Here, the processing of steps 331 to 41 will be explained with reference to FIG. 7 as follows. That is, if the result of the determination in step 34 in which the acceleration/deceleration correction coefficient α is decreased and the fuel injection amount is decreased is NO, the unit correction amount Δα' is assumed to be small and processing is performed to increase it (step 836). Furthermore, if the air-fuel ratio changes from the rich state to the low-low state before 1 sec has elapsed from time t4 (if the determination result in step S34 is YES), the process in step 314 is performed based on the count value C3 of the counter CNT3. It is determined whether the air-fuel ratio has changed from a rich state to a lean state continuously for 10 times or more within 1 sec after performing the step 538), and if the result of the determination is YES, the unit correction amount Δα is Assuming that " is large," processing is performed to reduce it (step 340).

The microprocessor 21 also operates for a predetermined period of time (for example, 10
The process shown in the flowchart in FIG. 5 is also carried out for each step (m5ec), in which the count value C1 of the counter CNT1 is incremented by 1 in step S51, and in step S52 it is determined whether or not the count value C1 is "0". S53
Then, the count value C1 is decremented by 1. In addition, the counter CNTl
can be counted from "0" to "¥FFJ", and when it is +1 when the count value force < rvpp, the count value is set to "0", and the color 7l-(tL is rOJ
If it is decremented by 1 at the time of , the count value is set to [\FFJ. Therefore, if the determination result in step S52 is YES, the count value of the counter CNTl is held at ¥FFJ, and if the determination result in step S52 is NO, the count value C1 of the counter CNTl is incremented by +1.

Next, the microprocessor 21 increments the count value C4 of the internally provided counter CNT4 by 1 (step 354), and then determines whether the count value C4 has become "5" (step 555), and the determination result is YE.
In the case of S, set the count value C4 to "0" (step 8
56). Therefore, if the flowchart shown in the figure is started every 101w5ec as described above, the judgment result in step S55 is YES once every 50m5ec.
Become S. Next, the microprocessor 21 determines whether the acceleration/deceleration correction coefficient α is 1.0 or not in step 55.
7) If the determination result is NO, it is determined whether the acceleration/deceleration correction coefficient α satisfies the relationship α>1.0.

If the judgment result is YES, the acceleration/deceleration correction coefficient α is decreased by a predetermined amount Δβ (step 559), and if the judgment result is NO, the acceleration/deceleration correction coefficient α is increased by a predetermined amount Δβ (step 560). , after which the process moves to another control step S61. That is, by performing the process of step 359.60, the acceleration/deceleration correction coefficient α decreases or increases at a predetermined slope until its value reaches 1.0, as shown in FIG. 7(C).

Although not explained in the above embodiment, the fourth
The processing shown in the flowchart is performed only when it is determined that the internal combustion engine is completely warmed up based on the detection results of the water temperature sensor 34 and the like. Also, although not explained in the above embodiment, the unit correction amounts Δα, Δ
Of course, the upper and lower limits of α' and the acceleration/deceleration correction coefficient α may be determined in advance. Furthermore, in the above-described embodiment, the presence or absence of an acceleration request or deceleration request is determined based on the rate of change in the opening degree of the throttle valve 32. Of course, the presence or absence of an acceleration or deceleration request may be determined based on the rate. In addition, in the above embodiment, when accelerating or decelerating, the acceleration/deceleration correction coefficient α is increased by the unit correction amount Δα or decreased by Δα゛. Of course, it is also possible to increase the correction coefficient α by the acceleration/deceleration correction amount W all at once or to partially decrease it all at once, and to hold that value until the acceleration or deceleration is completed. Deceleration correction amount w
, w' may of course be subjected to learning control as in this embodiment. Although not explained in the above embodiment, the microprocessor 21 performs the calculation shown in equation (1) using another routine, and injects the amount of fuel corresponding to the calculation result from the fuel injector 31 into the internal combustion engine. 26.

C Effects of the Invention] As explained above, the present invention provides an 02 sensor that outputs a signal corresponding to the oxygen concentration in exhaust gas of an internal combustion engine, and calculates an air-fuel ratio correction coefficient based on the output signal of the 02 sensor. a first correction coefficient calculating means for calculating a rotational speed of the internal combustion engine, and a determining means for determining whether or not it is time to request a change in the rotational speed of the internal combustion engine (in the embodiment, this comprises an opening sensor blade, a microprocessor 21, etc.); The acceleration/deceleration correction coefficient α is calculated based on the judgment result of the judgment means and the acceleration/deceleration correction N stored in the storage means (in the embodiment, the unit correction amounts Δα, Δα° stored in the RAM 23). and a second correction coefficient calculation means for calculating the air-fuel ratio correction coefficient calculated by the first calculation means, an acceleration/deceleration correction coefficient calculated by the second calculation means, and a basic injection amount. In a fuel supply device for an internal combustion engine, comprising an injection amount calculation means for calculating a fuel injection amount, and an injection means for supplying the internal combustion engine 1 with an amount of fuel corresponding to the calculation result of the injection amount calculation means, The acceleration/deceleration correction amount stored in the storage means is changed based on the output signal of the 02 sensor when a predetermined period of time has elapsed after the determination means has determined that it is time to request a change in the rotational speed of the internal combustion engine. Since it is equipped with a correction amount changing means,
Even when the characteristics of the internal combustion engine deteriorate due to aging or the like, there is an advantage that acceleration or deceleration can be performed smoothly.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of the present invention, FIG. 2 is a block diagram of an embodiment of the present invention, and FIGS. 3 to 5 are microprocessor 21.
FIG. 6 is a diagram illustrating air-fuel ratio feedback control, and FIG. 7 is a diagram illustrating acceleration/deceleration correction coefficient α. 1.26 is an internal combustion engine, 2 and 35 are 02 sensors, 3↓ is a first correction coefficient calculation means, 4 is a judgment means, 5 is a storage means,
6 is a second correction coefficient calculation means; 7 is an injection amount calculation means; 8
9 is an injection means, 9 is a change means, 21 is a microprocessor, 22 is a ROM, and 23 is a RAM. 24 is an input section, 5 is an output section, 27 is an air cleaner, 28
is the air flow meter, 29 is the throttle chamber, 30
3I is an intake manifold, 3I is a fuel injector, 32 is a throttle valve, 33 is an opening sensor, 34 is a water temperature sensor, 36.37 is an AD converter, and 38 is a crank angle sensor. Patent Applicant Fujitsu Ten Ltd. Representative Patent Attorney Gobe Tamamushi (one other person) Block diagram of the present invention No. 1rIA Block diagram of an embodiment of the present invention Fig. 2 Fig. 3

Claims (1)

[Scope of Claims] An O_2 sensor that outputs a signal corresponding to the oxygen concentration in exhaust gas of an internal combustion engine; and a first correction coefficient calculation means that calculates an air-fuel ratio correction coefficient based on the output signal of the O_2 sensor. , determining means for determining whether or not it is time to request a change in the rotational speed of the internal combustion engine; and calculating an acceleration/deceleration correction coefficient based on the determination result of the determining means and the acceleration/deceleration correction amount stored in the storage means. a second correction coefficient calculation means for calculating the amount of fuel to the internal combustion engine based on the air-fuel ratio correction coefficient calculated by the first calculation means, the acceleration/deceleration correction coefficient calculated by the second calculation means, and the basic injection amount; In a fuel supply device for an internal combustion engine, comprising an injection amount calculation means for calculating a fuel injection amount, and an injection means for supplying the internal combustion engine 1 with an amount of fuel corresponding to the calculation result of the injection amount calculation means, Changing means for changing the acceleration/deceleration correction amount stored in the storage means based on the output signal of the O_2 sensor after a predetermined period of time after the judgment means judges that it is time to request a change in the rotational speed of the internal combustion engine. A fuel supply device for an internal combustion engine, characterized by comprising: