JPH0363668B2 - - Google Patents

Description

TECHNICAL FIELD The present invention relates to a control device for controlling ignition timing and fuel supply of an internal combustion engine.

Conventional technology Conventionally, among the control devices that control the ignition timing and fuel supply of internal combustion engines, the ignition timing control device that controls the ignition timing is, for example, “ECCS L Series Engine Technical Explanation, published by Nissan Motor Co., Ltd., June 1971. There is something like the one described in "Book, pages 46-54".

Such an ignition timing control device will be explained with reference to FIG.

The control unit 1 of this ignition timing control device includes a CPU (central processing unit) 11, a ROM (read only memory) 12, and a RAM (random memory).
access memory) 13 and I/O (input/output device)
It is composed of a microcomputer consisting of 14, etc., and controls the ignition timing based on a program stored in its ROM 12.

The ROM 12 of the control unit 1 contains a table X of ignition timing value data corresponding to the engine speed as shown in FIG. 2, and a table A table Y of ignition timing value data is stored.

The control unit 1 also includes an air flow meter 3 that counts the angle signal _P1 from the crank angle sensor 2 that detects the crank angle to calculate the engine speed, and detects the amount of air taken into the intake pipe of the engine. The intake air amount is calculated based on the intake pipe intake air amount signal _P2 from the intake pipe.

Then, when the throttle close signal _P3 is input from the throttle close switch 4 which detects that the throttle valve is fully closed, table X is selected and the ignition timing value data corresponding to the engine speed is read out. , when the throttle close signal P ₃ is not input, table Y is selected and the ignition timing value data corresponding to the engine speed and intake pipe intake air amount is read out, and the reference position signal P ₄ from the crank angle sensor 2 is read out. Based on this, the power transistor 5 is turned off at a timing corresponding to the read ignition timing value data.

As a result, the primary current flowing from the battery 6 to the primary winding 7a of the ignition coil 7 is cut off, a high voltage is generated in the secondary winding 7b, and this high voltage is distributed by the distributor 8. Then, power is sequentially supplied to the spark plugs 9A to 9D to generate spark discharge and ignite the spark plugs.

Next, as a fuel supply control device that controls fuel supply, for example, the one described in "Automotive Engineering Complete Book Volume 4, Gasoline Engine, Pages 201 to 204, published by Sankaido Co., Ltd., July 20, 1980" is used. There is something.

Such a fuel supply control device will be explained with reference to FIG. 4.

In this fuel supply control device, after fuel is sucked and pressure-fed from a fuel tank 21 to a fuel pump 22, pulsation is suppressed by a fuel damper 23, and dirt and moisture are removed by a fuel filter 24. The fuel is then supplied to a fuel injector 26 attached to the engine 25. Note that the pressure regulator 27 keeps the fuel pressure supplied to the fuel injector 26 constant.

On the other hand, air is taken into the engine via an air filter 31 and then supplied to each cylinder of the engine 25 from an intake manifold 34 via an air flow meter 32 and a throttle valve 33. Note that the air regulator 35 introduces auxiliary air into the intake manifold 34 at the time of startup or warm-up reversal, thereby increasing the amount of intake air.

The control unit 41 is composed of a microcomputer, similar to the control unit 1 in FIG. Throttle close signal from the water temperature sensor 42, water temperature signal from the water temperature sensor 42, battery voltage detection signal (not shown),
A starter signal from a starter switch that detects the operation of the starter motor, an angle signal from a crank angle sensor (not shown) that detects the crank angle, etc. are input, and the fuel injector 26 of each cylinder is controlled based on these input results. At the same time, the fuel supply amount is controlled by controlling the drive once per revolution of the engine.

In other words, the control unit 41 controls the injection amount (basic injection amount) T proportional to the intake air amount per revolution based on the intake air amount signal from the air flow meter 32 and the angle signal from the crank angle sensor. _p is calculated by calculating T _p =K·Q/N. In addition, Q is the amount of intake air,
N is the engine speed.

Then, this basic injection amount T _p is corrected as follows based on detection signals from various sensors.

Increased amount correction after starting (KAS): This is a correction to obtain smooth starting characteristics and a smooth transition from starting to idling.The correction coefficient KAS takes the initial value shown in Figure 5 when the starter motor is turned on. , becomes "0" as time passes.

Post-idle increase correction (KAI): This is a correction to smooth the start when there is insufficient warm-up.The correction coefficient kAI becomes the initial value shown in Figure 6 immediately after the idle switch is turned off, and the time increases. The elapsed time will both be "0".

Battery voltage correction (TS): Correction of changes in the effective valve opening time of the fuel injector due to fluctuations in the driving voltage (battery voltage) of the fuel injector.The correction value TS is determined by referring to Fig. 7. Find it as TS=a+b(14-VB). Note that a and b are each constant, and VB
is the battery voltage.

Water temperature increase correction (FT): This is a correction when the engine is not sufficiently warmed up.The correction coefficient FT is shown in Figure 8.

Also, when starting the engine, calculate T _p1 = T _p × (1 + KAS) × 1.3 + TS T _p2 = TST × KNST × KTST, and use the larger value of T _p1 or T _p2 as the fuel injection amount. . Note that TST is the basic injection amount at startup (Figure 9), KNST is the rotation speed correction coefficient (Figure 10), and KTST is the time correction coefficient (Figure 11).
Figure).

Note that in the above explanation, the ignition timing control device and fuel supply control device that constitute the internal combustion engine control device were individually described, but when controlling the same engine, the ignition timing and fuel supply control devices can be controlled by the same control unit. control.

In this way, conventional internal combustion engine control devices control the fuel supply amount according to the engine speed and intake air intake amount, and the ignition timing is controlled depending on the engine speed when idling, and at other times. At the time, the engine speed and the amount of air taken into the intake pipe were uniquely determined and controlled.

However, especially when the throttle opening is fully closed or close to fully closed, a sonic state is realized in the throttle section, and the amount of air sucked into the intake pipe through the throttle is constant (determined only by the throttle opening area). (2), fuel is supplied in proportion to the reciprocal of the engine speed due to fluctuations in engine speed during transients or load fluctuations, but the actual amount of intake air flowing into the cylinder is The air-fuel ratio becomes unstable because it changes with a substantially first-order lag response to changes in engine speed due to the influence of pipe volume and the like.

Therefore, especially when the engine speed is suddenly reduced due to clutch engagement or the like, the air-fuel ratio becomes excessively rich, and there is a risk that engine stalling may occur.

Furthermore, since the air-fuel ratio is unstable, there is a possibility that the generation pattern of torque generated by the engine may differ depending on the base air-fuel ratio (set base air-fuel ratio).

Moreover, as mentioned above, the actual amount of intake air flowing into the cylinder changes with a first-order lag relative to changes in engine speed, so regardless of the base air-fuel ratio, the torque generated by the engine also changes as the engine speed changes. It changes with a first-order lag.

Therefore, even if the engine speed is reduced due to clutch engagement or the like, the increase in generated torque is delayed, and there is a possibility that engine stalling may occur more easily.

Purpose This invention has been made in view of the above points, and is aimed at reducing the difference in the set base air-fuel ratio caused by the delay in the response of the cylinder intake air amount when the engine speed fluctuates during transients or load fluctuations. By suppressing differences in the torque generation pattern and correcting the response delay of the generated torque, it is possible to prevent the engine from stalling even when pulling out of a gear from a high rotation speed or when loads such as clutch engagement are applied. The purpose is to

Configuration Therefore, as shown in FIG. 12, the control device for an internal combustion engine according to the present invention changes with a delay in response to a change in engine speed predicted and calculated by the actual cylinder intake air amount calculating means A. The fuel supply amount control means B controls the fuel supply amount based on the actual cylinder intake air amount, and the actual torque correlation value calculation means C calculates the actual torque of the engine generated corresponding to the actual cylinder intake air amount. Calculate the correlated values,
It also correlates with the ideal engine torque generated in response to the virtual cylinder intake air amount, which is predicted and calculated by the virtual cylinder intake air amount calculation means D, assuming that there is no response delay to changes in engine speed. The ideal torque correlation value calculation means E calculates the value, and the deviation value is calculated based on the actual torque correlation value calculated by the actual torque correlation value calculation means C and the ideal torque correlation value calculated by the ideal torque correlation value calculation means E. Based on the deviation value between the actual torque correlation value and the ideal torque correlation value calculated by the means F, the ignition timing correction means H corrects the ignition timing according to the operating state of the engine calculated by the ignition timing calculation means G. This is how it was done.

Embodiments Hereinafter, embodiments of the present invention will be described with reference to FIG. 13 and subsequent figures of the accompanying drawings. In addition, Figure 1 or 4
The same parts as those in the figures are given the same reference numerals, and explanations of those parts will be omitted.

FIG. 13 is a block diagram showing one embodiment of the present invention.

The control circuit 51 includes an actual cylinder intake air amount calculation means A, a fuel supply amount control means B, shown in FIG.
Actual torque correlation value calculation means C, virtual cylinder intake air amount calculation means D, ideal torque correlation value calculation means E,
This circuit serves as a deviation value calculation means F, an ignition timing calculation means G, and an ignition timing correction means H, and includes a CPU (central processing unit) 52 and a ROM (read-only memory).
53, RAM (Random Access Memory) 5
4 and an I/O (input/output device) 55 with a built-in A/D converter.

The control circuit 51 calculates the actual cylinder intake air amount, which changes with a response delay in response to changes in engine speed, based on a program stored in the ROM 53, and generates data corresponding to the actual cylinder intake air amount. a value correlated to the engine's actual torque, a calculation calculation of the virtual cylinder intake air amount assuming that there is no response delay to changes in engine speed, and an ideal engine value that occurs in response to the virtual cylinder intake air amount. It calculates the value correlated with torque, the deviation value between the actual torque correlation value and the ideal torque correlation value, controls the fuel supply amount, calculates the ignition timing, corrects the ignition timing, and controls the ignition timing.

The ROM 53 contains data necessary for calculating the cylinder intake air amount, calculating the actual torque correlation value, calculating the ideal torque correlation value, calculating the deviation value, calculating the fuel supply amount, calculating the ignition timing, and correcting the ignition timing. It also stores tables.

Furthermore, as shown in FIG. 14, the portion of the I/O 55 that is related to the control of the power transistor 5 includes an ADV (advance value) register 551 to which ignition timing data ADD ₁ is set, and an ADV (advance value) register 551 that is reset by a reset pulse RS ₁ . a counter 552 that counts the angle (1° pulse) signal _P2 from the crank angle sensor 2;
When the counter 552 is reset, the power transistor 5 is turned on and the ADV register 5 is turned on.
A comparator 5 that turns off the power transistor 5 when the ignition timing data ADD ₁ set in 51 matches the count value of the counter 552.
It consists of 53.

Furthermore, as shown in FIG. 15, the portion of the I/O 55 that is related to the control of the power transistor 56 for driving the fuel injector (fuel injection valve) 26 is connected to the EGI, which is set with the fuel injection amount data ADD ₂ .
(Fuel injection) register 555 and reset pulse
When the counter 556 is reset by RS ₂ and counts clock pulses, the power transistor 56 is turned on when the counter 556 is reset, and the fuel injection amount data ADD ₂ set in the EGI register 555 and the count value of the counter 556 are and a comparator 557 that turns off the power transistor 56 when they match.

The starter switch 57 is a switch that is turned on when the engine is in a starting state, and inputs a starter signal P ₅ corresponding to that state to the I/O 55 of the control circuit 51.

Further, the idle switch 58 is a switch that is turned on when the engine is in an idling state, and inputs an idle signal P ₆ corresponding to that state to the I/O 55 of the control circuit 51.

Note that in place of the idle switch 58, a throttle close switch that detects that the throttle valve is fully closed may be used.

The reference pulse generator 60 generates a reference signal P8 every time the engine rotates once, and outputs the reference signal _P8 to the I/O of the control circuit 51.
55. Note that this reference signal _P8 is the first
This becomes the reset pulse _RS2 of the counter 556 in FIG.

Although not shown, a water temperature detection signal from a water temperature sensor and a voltage detection signal of the battery 6 are also input to the I/O 55 of the control circuit 51.

Next, the operation of the embodiment configured as described above will be explained with reference to FIG. 16 and subsequent figures.

First, the principles of fuel injection amount control and ignition timing control in this control device will be described.

Referring to Fig. 16, in the so-called L-Jetro type control device that has been used conventionally, when the engine throttle valve is fully closed, the engine speed N is stepped from 700 rpm to 600 rpm as shown in Fig. 16A. When the intake pipe intake air amount per unit time Q, the cylinder intake air amount Qa per cylinder cycle, the fuel injection amount per cylinder per cycle T _p ,
The air-fuel ratio Y and the shaft torque T are respectively shown by solid lines in FIG.

In other words, the intake pipe intake air amount Q remains approximately constant regardless of changes in the engine speed N since a sonic state is achieved when the throttle is fully closed.

The cylinder intake air amount Qa changes in a first-order delayed response to changes in the engine speed N due to the influence of the intake pipe volume, cylinder stroke volume, and the like.

The fuel injection amount T _p is expressed by the engine speed N and the intake pipe intake air amount Q as T _p =K・Q/N,
When the intake pipe intake air amount Q is constant, the amount is proportional to the reciprocal of the engine speed N.

Since the air-fuel ratio Y is an amount in which the fuel injection amount T _p is proportional to the reciprocal of the engine speed N, it becomes unstable when the engine speed N suddenly changes, and becomes rich when the engine speed N suddenly changes. The air-fuel ratio gradually returns to the base air-fuel ratio.

The shaft torque T has a response delay due to a change in the engine speed N due to a response delay in the cylinder intake air amount Qa, and also due to a change in the air-fuel ratio Y, that is, due to a difference in the set base air-fuel ratio. The response behavior (occurrence pattern) is different as shown by the solid line, broken line, and dashed-dotted line in the figure.

The solid line in FIG. 16 shows the behavior when the air-fuel ratio Y is rich, the broken line shows the behavior when the excess air ratio λ is λ=1, and the dashed-dotted line shows the behavior when the air-fuel ratio Y is lean.

Therefore, if we first control the fuel injection amount T _p to be proportional to the cylinder intake air amount Qa, then
The generation pattern (behavior) of the shaft torque T is approximately the same for each set base air-fuel ratio, as shown in FIG. 17E (the meaning of each line is the same as in FIG. 16F).

However, the generation pattern when the shaft torque T makes an ideal response with no response delay to fluctuations in the engine speed N is as shown by the two-dot chain line in Fig. 17E, and the engine speed is still There is a response delay due to a response delay in the cylinder intake air amount Qa to a change in the number N.

Incidentally, the ignition timing and shaft torque have a relationship as shown in FIG. 18, and by changing the ignition timing, the shaft torque also changes.

Therefore, the difference between the ideal torque of the engine (ideal torque) shown by the two-dot chain line in Fig. If the ignition timing is corrected by the amount by which the corrected torque amount ΔT shown in the figure is obtained, the ideal torque can be obtained as the actual torque.

In this way, the generated shaft torque T due to the set base air-fuel ratio is supplied by supplying the fuel injection amount T _p commensurate with the cylinder intake air amount Qa (actual cylinder intake air amount).
After suppressing the difference in the generation pattern, the ignition timing is corrected to bring the actual torque closer to the ideal torque.

Next, the control of the fuel injection amount and the control of the ignition timing will be specifically described.

First, the actual cylinder intake air amount taken into the engine cylinders, that is, the actual cylinder intake air amount (the cylinder intake air amount that changes with a delay in response to changes in engine speed) T ₂ is calculated when the engine is idling. In other words, when the throttle is fully closed (a state in which sonic flow is realized), T ₂ = (1-α)・T ₂ ′+α depending on the engine speed N and the amount of intake air intake Q per unit time.・It has been confirmed that it can be expressed approximately as 2Q/CN. Note that T ₂ ′ is the cylinder intake air amount one cycle before,
C is the number of cylinders, α is a constant, and if the volumetric efficiency is η, the cylinder stroke volume is v, and the intake pipe volume is V, then α
=η·v/V.

Therefore, engine speed N and intake pipe intake air amount Q
Measure and predict the actual cylinder intake air amount _T2 ,
By supplying the fuel injection amount T _p proportional to the actual cylinder intake air amount T ₂ , the air-fuel ratio can be kept approximately constant even when the engine speed fluctuates, and the shaft torque generation pattern can be maintained regardless of the set base air-fuel ratio. (behavior) will be almost the same.

Also, assuming that there is no response delay due to engine speed fluctuations, the ideal cylinder intake air amount (ideal cylinder intake air amount) T ₁ is equal to the engine speed N
and the intake pipe intake air amount Q, it can be expressed as T ₁ =2Q/CN.

Here, if the air-fuel ratio is kept approximately constant by controlling the fuel injection amount as described above, the torque generated by the engine is considered to be proportional to the cylinder intake air amount Qa, so the actual torque and ideal torque are The difference (torque correction amount) ΔT is the actual cylinder intake air amount
It is considered that it is proportional to the difference between T ₂ and the ideal cylinder intake air amount T ₁ . In other words, the relationship ΔT∝T ₁ −T ₂ holds true.

Here, only when the throttle is fully closed, the intake air amount Q in the intake pipe remains approximately constant because a sonic flow is realized in the throttle portion as described above.

Therefore, if Q=constant and a constant K ₁ = 2Q/C is set, the above-mentioned ideal cylinder intake air amount T ₁ and actual cylinder intake air amount T ₂ are as follows: T ₂ = (1-α)・T ₂ ' +α·K ₁ ·1/N T ₁ =K ₁ ·1/N, which can be expressed as a function of engine speed N.

A value proportional to the corrected torque amount ΔT can be calculated using these actual cylinder intake air amount T ₂ and ideal cylinder intake air amount T ₁ .

Therefore, the difference (T ₁ - _{T 2} ) between the ideal cylinder intake air amount T ₁ and the actual cylinder intake air amount T ₂ , that is, the value proportional to the corrected torque amount ΔT, is calculated.
This calculation result is converted into an ignition timing correction amount using a predetermined function or table data, and the ignition timing is corrected by this correction amount to control the ignition timing to respond to the cylinder intake air amount. It is possible to correct the torque response delay due to the delay.

Next, the fuel injection amount control and ignition timing control operations executed by the control circuit 51 in FIG.
The explanation will be given with reference to the following figures.

First, the control circuit 51 receives a starter signal from the starter switch 57, although the flow is not shown.
P ₅ is stored at a predetermined address in the RAM 54 (hereinafter referred to as "address DI ₁ "), and the idle switch 5 is
The idle signal P ₆ from the RAM 54 is stored at a predetermined address (hereinafter referred to as "address DI ₂ ").

Further, the angle (1° pulse) signal P ₁ from the crank angle sensor 2 is counted for a certain period of time, for example, 12.5 msec, and the counted value is set as the engine rotational speed N to a predetermined address in the RAM 54 (hereinafter referred to as "address").
DN).

Furthermore, the intake pipe intake air amount signal P ₂ from the air flow meter 3 is converted to A-
The D-converted result is taken as the intake pipe intake air amount Q.
A predetermined address of RAM54 (hereinafter referred to as “address”)
DQ).

Based on these input data, the control circuit 51 calculates the fuel injection amount T _p and ignition timing in the background job as described later, and also uses the crank angle sensor as shown in FIG. By inputting the reference position signal _P4 from 2,
For each cycle, that is, for each ignition, ignition timing data ADD ₁ is set in the ADV register 551 in FIG. 14, the fuel injection amount T _p is updated, and the actual cylinder intake air amount T ₂ is updated.

In addition, the values of the updated fuel injection amount T _p and the actual cylinder intake air amount T ₂ from one cycle ago are respectively
stored as T _p ′ and T ₂ ′.

Next, the fuel injection amount calculation process executed by the control circuit 51 in the background job will be described with reference to FIG. 20 as well.

First, the data on the engine speed N stored at the address DN of the RAM 54 and the data on the intake pipe intake air amount Q stored at the address DQ are read out.

Then, the data at the address DI2 of the RAM ₅₄ is read to determine whether the idle switch 58 is in the on state, that is, whether the engine is in the idling state.

As a result of this determination, if the idle switch 58 is not in the ON state, the normal fuel injection amount T _p is calculated as T _p =K・Q/N based on the engine speed N and the intake pipe intake air amount Q. Calculate by

On the other hand, if the idle switch 58 is in the on state, the engine speed N, the intake pipe intake air amount Q
Based on the fuel injection amount T _p one cycle (one ignition) before, calculate the fuel injection amount T _p at idling as T _p2 = (1-α)・T _p ′+α・K・Q/N. Calculate by

Note that, as described above, this fuel injection amount T _p is updated every cycle, and the value one cycle before becomes the fuel injection amount T _p '.

Thereafter, as in the past, a corrected fuel injection amount TI is calculated by correcting the fuel injection amount T _p based on detection signals from various sensors, for example, by calculating TI=T _p (FT+KAS+KAI)+TS.

The calculated corrected fuel injection amount TI is then set in the EGI register 555 in FIG. 15 as fuel injection amount data ADD ₂ .

15 and 21, the time point Ta at which the counter 556 is reset with the reference signal P ₈ (reset pulse RS ₂ ) generated from the reference pulse generator 60 every revolution of the engine is determined. ₁ , the comparator 557 turns on the power transistor 56 and turns on the fuel injector 26, so that fuel injection is started.

Then, at time _Tb2 when the count value of the counter 556 matches the set value of the EGI register 555,
Since the comparator 557 turns off the power transistor 56 and turns off the fuel injector 26, fuel injection ends.

In this way, the actual amount of intake air taken into the cylinders of the engine (actual cylinder intake air amount) is calculated based on the engine speed N and the intake pipe intake air amount Q, and the calculated cylinder intake air amount is Since the appropriate fuel injection amount is supplied, it is possible to suppress differences in the shaft torque generation pattern (behavior) depending on the set base air-fuel ratio.

Next, the ignition timing calculation process executed by the control circuit 51 in the background job will be described with reference to FIG. 22.

First, the data at address _DI1 of the RAM 54 is read to determine whether the starter switch 57 is on, that is, whether the engine is in the starting state.

As a result of this determination, if the starter switch 57 is in the ON state, the ignition timing during cranking is calculated and stored at a predetermined address in the RAM 54 (hereinafter referred to as "address ADVL").

On the other hand, if the starter switch 57 is not on, then the data at address _DI2 of the RAM 54 is read to determine whether the idle switch 58 is on, that is, whether the engine is in an idling state.

As a result of this determination, if the idle switch 58 is in the ON state, the engine speed N data stored in the address DN of the RAM 54 is read out, and the ignition timing value data corresponding to the engine speed N is read out.
After reading out the table stored in the ROM 53 and calculating the set ignition timing A during idling, an ignition timing correction calculation is performed to correct this ignition timing A according to the correction torque amount ΔT mentioned above, and the ignition timing is calculated by this correction calculation. Ignition timing AD to RAM54 address
Store in ADVL.

On the other hand, if the idle switch 58 is not in the ON state, the data of the engine speed N stored in the address DN of the RAM 54 and the address
The data of the intake pipe intake air amount Q stored in the DQ is read out, the ignition timing value data corresponding to the engine speed N and the intake pipe intake air amount Q is read out from the table stored in the ROM 53, and the ignition timing AD
is stored in address ADVL of RAM54.

Ignition timing set in this address ADVL
As mentioned above, AD performs a predetermined conversion process in the interrupt routine for each ignition, and the ignition timing data
It is set as ADD ₁ in the ADV register 551 in FIG.

Next, we will discuss the ignition timing correction calculation process in the second section.
This will be explained with reference to FIG.

First, the engine speed N stored in the address DN of the RAM 54 and the actual cylinder intake air amount T ₂ ' one cycle before are read.

After calculating (1/N) from the engine speed N, the ideal cylinder intake air amount T ₁ is calculated by calculating T ₁ =K ₁ ·1/N.

After that, the actual cylinder intake air amount from 1 cycle before
The current ideal cylinder intake air amount T ₁ calculated as T ₂ ′
Based on this, the actual cylinder intake air amount T ₂
is calculated by calculating T ₂ = (1-α)·T ₂ ′+α·T ₁ . Note that α is the constant described above.

Then, based on the calculated current ideal cylinder intake air amount T ₁ and actual cylinder intake air amount T ₂ , the corrected torque amount ΔT is calculated by calculating ΔT=T ₁ −T ₂ .

Thereafter, the ignition timing correction amount ΔA is determined according to a preset function F by calculating ΔA=F(ΔT) or by reading it from a table.

In addition, the function F is, for example, when ΔT≧ΔT ₁ , F(ΔT)≧0; when ΔT ₁ >ΔT>ΔT ₂ , F(ΔT)=0; when ΔT≦ΔT ₂ , F(ΔT)≦0. This is a satisfying function. Note that ΔT ₁ and ΔT ₂ are constants, and ΔT ₁ ≧0 and ΔT ₂ ≦0.

Next, using the ignition timing correction amount ΔA calculated in this way and the already calculated set ignition timing A, the corrected ignition timing AD is calculated by calculating AD=ΔA+A, and is shown in FIG. As shown,
This corrected ignition timing AD is the address of RAM54.
Store in ADVL.

Note that the corrected torque amount ΔT can also be calculated by calculating ΔT=T ₁ /T ₂ .

In this case, the constant ΔT ₁ in the function F,
Let ΔT ₂ be ΔT ₁ ≧1,0, 0≦ΔT ₂ ≦1.0.

Further, the corrected ignition timing AD can also be calculated by calculating AD=ΔA·A. In this case, the function F is defined as: When ΔT≧ΔT ₁ , F(ΔT)≧1.0 When ΔT ₁ >ΔT>ΔT ₂ , F(ΔT)=1.0 When ΔT≦ΔT ₂ , 0≦F( ΔT)≦1.0. Note that ΔT ₁ and ΔT ₂ are constants, and ΔT ₁ ≧1.0, 0≦ΔT ₂ ≦1.0.

In this way, the difference between the actual cylinder intake air amount and the ideal cylinder intake air amount during idling, that is, the actual cylinder intake air amount that occurs in response to the difference in the actual cylinder intake air amount that changes with a response delay to changes in engine speed. The ignition timing is corrected according to the difference between the ideal torque generated in response to the virtual cylinder intake air amount and the difference is eliminated, assuming that there is no response delay to changes in torque and engine speed. Therefore, there is no response delay in the generated torque due to fluctuations in engine speed.

This prevents the engine from stalling when the engine is idling, when a gear is removed from a high rotational speed, or when a load such as clutch engagement is applied.

The idling state of the engine is defined as: when the throttle valve of the engine is fully closed or close to fully closed, when the above conditions are satisfied, and when the engine speed is below a predetermined engine speed, when the above conditions are satisfied, and when the gear is in neutral, when the above conditions are satisfied, and when the intake air flow rate, fuel injection amount _Tp , or intake pipe pressure is below the set value, etc., or some combination of these. It means when all conditions are satisfied.

In this embodiment, the fuel injection amount T _p and the actual cylinder intake air amount T ₂ are calculated using a weighted average value, but they can be calculated in substantially the same way using a moving average value. In other words, calculate Tp=1/n _o-1 〓 ⁱ⁼⁰ (Q/N)i, T ₂ =1/n _o-1 〓 ⁱ⁼⁰ (K ₁・1/N)i. . Note that in these equations, (Q/N)i and (K ₁ ·1/N)i mean (Q/N) and (K ₁ ·1/N) i cycles before.

In this case, the past (n-1) is stored in the RAM 54.
(Q/N) and (K ₁・1/N) before the cycle
It is necessary to memorize the data.

FIGS. 24 and 25 are flowcharts showing an example of the fuel injection amount calculation process and the ignition timing calculation process executed by the control circuit in another embodiment of the present invention.

In this embodiment, the fuel injection amount and ignition timing are corrected only during idling in the above embodiment, but the fuel injection amount and ignition timing are always corrected in the operating range other than during cranking. This is what I did.

In this case, the constant α in the calculation of the fuel injection amount T _p and the correction calculation of the ignition timing is switched by turning the idle switch 58 on and off.

It is a function of engine speed N.

It is assumed to be a function of the amount of intake air Q in the intake pipe.

Combining some of the above.

By doing this, in addition to the effects of the above-described embodiments, shocks caused by torque fluctuations that occur when feedback control of the air-fuel ratio or load fluctuations such as turning on and off the air conditioner while driving at a constant speed, etc., can be softened. be able to.

FIG. 26 is a block diagram showing still another embodiment of the present invention. Note that only the points different from the embodiment shown in FIG. 13 will be explained below.

First, in this embodiment, an intake pipe pressure sensor 59 for detecting the pressure inside the intake pipe is provided in place of the air flow meter 3 shown in FIG. signal
_P7 is input to the I/O 55 of the control circuit 54.

That is, in general, the cylinder intake air amount Qa taken into the engine cylinder can be expressed as a function of the intake pipe pressure P and the engine speed N.

In this case, since the main effect of the engine speed N is the intake efficiency, there is no significant difference even if it is expressed as a function of the intake pipe pressure P, especially in a relatively narrow range of engine speeds such as during idling (No. 27 (see figure).
In other words, the cylinder intake air amount Qa can be expressed as Qa=F(P) or Qa=G(N,P).

Therefore, the control circuit 51 first sends the intake pipe pressure signal P ₇ from the intake pipe pressure sensor 59 to the I/O 55.
The result of A/D conversion by the A/D converter is stored as the intake pipe pressure P at a predetermined address (hereinafter referred to as "address DP") in the RAM 54.

Then, as shown in FIG. 28, the control circuit 51 reads out the engine speed N data stored in the address DN of the RAM 54 and the intake pipe pressure P data stored in the address DP, and controls these engine speeds. From the number N and the intake pipe pressure P, use the function F or G or table data to calculate the cylinder intake air amount.
Find Qa (actual cylinder intake air amount T ₂ ).

Then, this calculated cylinder intake air amount Qa
Calculate the fuel injection amount T _p proportional to , calculate the corrected fuel injection amount TI, and use this corrected fuel injection amount TI
Set in EGI register 555.

Regarding the control of the ignition timing, although illustration is omitted, the parameters of the ignition timing during normal operation in the above embodiment are determined from the engine speed N and the intake air intake amount Q (see Fig. 22). and the intake pipe pressure P, or the engine speed N and the cylinder intake air amount Qa.

If an intake pipe pressure sensor is used in place of the air flow meter as in this embodiment, the cost will be reduced.

Effects As explained above, according to the present invention, the torque response behavior due to the difference in the set base air-fuel ratio caused by the response delay of the cylinder intake air amount when the engine speed fluctuates during transient or load fluctuations can be improved. It is possible to suppress the difference in (occurrence pattern) and correct the delay in torque response, so it can prevent the engine from stalling when a load is applied such as when pulling out of a gear from a high rotation speed or when a load is applied such as clutch engagement. disappears.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an example of a conventional ignition timing control device for an internal combustion engine, and FIGS. 2 and 3 are
A diagram illustrating an example of an engine speed-advance value characteristic and an engine speed/intake air amount-advance value characteristic for explaining the ignition timing data stored in the ROM in FIG. 1;
FIG. 4 is a block diagram showing an example of a conventional fuel supply control device for an internal combustion engine, and FIGS. 5 to 11 are characteristic diagrams of correction coefficients used to correct the fuel injection amount. FIG. 12 is a functional block diagram showing the configuration of this invention, FIG. 13 is a block diagram showing an embodiment of this invention, and FIGS. A partial block configuration diagram, FIG. 16 is a diagram showing an example of changes in intake pipe intake air amount, cylinder intake air amount, fuel injection amount, air-fuel ratio, and shaft torque with respect to changes in engine speed, and FIG. Similarly, Fig. 18 is a diagram showing an example of changes in intake pipe intake air amount, cylinder intake air amount, fuel injection amount, shaft torque, and correction torque amount with respect to changes in engine speed, and shows the relationship between ignition timing and torque. A diagram showing an example, FIG. 19 is a main part flow diagram showing an example of the fuel injection control and ignition control operations executed by the control circuit of FIG. 13, and FIG. 20 is a diagram showing an example of the fuel injection amount calculation process. 21 is a timing chart of each part of FIG. 15, which is also provided for explanation, and FIG. 22 is a flow diagram showing an example of the ignition timing calculation process, and FIG.
22 is a flowchart showing an example of the ignition timing correction calculation process, and FIGS. 24 and 25 show the fuel injection amount calculation process and the ignition timing calculation process executed by the control circuit in another embodiment of the present invention. FIG. 26 is a flowchart showing an example of the process, FIG. 26 is a block diagram showing another embodiment of the present invention, and FIG. A line diagram showing an example of change,
FIG. 28 is a flowchart showing an example of the fuel injection amount calculation process executed by the control circuit of FIG. 26. 2... Crank angle sensor, 3... Air flow meter, 5, 56... Power transistor, 6... Battery, 7... Ignition coil, 8... Distributor, 9A to 9D... Spark plug, 51... Control circuit, 57... Starter switch, 58... Idle switch, 59... Intake pipe pressure sensor, 6
0...Reference pulse generator.

Claims (1)

[Claims] 1. In a control device that controls the ignition timing and fuel supply of an internal combustion engine, the actual cylinder intake air amount, which changes with a response delay to changes in engine speed, is predicted based on the engine speed. an actual cylinder intake air amount calculation means for calculating an actual cylinder intake air amount; an actual torque correlation value calculation means for calculating a value correlated to the actual torque of the engine generated corresponding to the actual cylinder intake air amount; A virtual cylinder intake air amount calculation means that predicts and calculates a virtual cylinder intake air amount based on the engine rotation speed assuming that there is no response delay, and an ideal engine that occurs in response to the virtual cylinder intake air amount. An ideal torque correlation value calculation means for calculating a value correlated to torque, and a deviation between the actual torque correlation value and the ideal torque correlation value based on the calculation result of the actual torque correlation value calculation means and the ideal torque correlation value calculation result. a deviation value calculation means for calculating the value;
a fuel supply amount control means for controlling a fuel supply amount to supply an amount of fuel commensurate with the cylinder intake air amount based on the calculation result of the actual cylinder intake air amount calculation means; and an ignition timing according to the operating state of the engine. ignition timing calculation means for calculating the ignition timing, and ignition timing correction means for correcting the ignition timing calculated by the ignition timing calculation means so that the actual torque of the engine approaches the ideal torque based on the deviation value calculated by the deviation value calculation means. A control device for an internal combustion engine, comprising: 2. The control device for an internal combustion engine according to claim 1, wherein the actual cylinder intake air amount calculation means calculates the cylinder intake air amount based on the intake pipe intake air amount of the engine and the engine speed. 3. The control device for an internal combustion engine according to claim 1, wherein the actual cylinder intake air amount calculation means calculates the cylinder intake air amount based on the intake pipe pressure of the engine.