JPH0147612B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a fuel supply control method during acceleration of an internal combustion engine, which increases the amount of fuel supplied during acceleration of the internal combustion engine to improve acceleration performance.

The valve opening time of the fuel injection device of an internal combustion engine, especially a gasoline engine, is set to a standard value depending on the engine speed and the absolute pressure inside the intake pipe, and the specifications representing the operating state of the engine, such as the engine speed and the inside of the intake pipe. Constants and/or coefficients are added by electronic means depending on the absolute pressure of the engine, engine water temperature, throttle valve opening, exhaust concentration (oxygen concentration), etc.
The present applicant has proposed a fuel supply control method in which the fuel injection amount is determined by multiplication, and the air-fuel ratio of the air-fuel mixture supplied to the engine is thereby controlled.

In this control method, the period during which the driver requests acceleration starts from the time when the accelerator is depressed, and continues while the acceleration of the accelerator depression is showing a positive acceleration. The acceleration is determined by, for example, detecting the opening θth of the throttle valve in the intake pipe, which is detected every time a predetermined sampling signal occurs, and calculating the amount of change Δθn in the opening between the current generation and the previous generation of the sampling signal. Find the difference ΔΔθn between the amount of change Δθn at the current occurrence of the signal and the amount of change Δθn _-1 at the previous occurrence, and calculate the period during which the difference ΔΔθn can be detected as acceleration and the difference takes a positive value (ΔΔθn ≧ 0). This is the period during which the driver requests acceleration. That is, the period from time a ₁ to time a ₂ shown in FIG. 1B is a period during which acceleration is required for which ΔΔθn is positive, and time a ₂ represents the maximum demand for acceleration. Therefore, by setting the increase value at the time point _a2 to be the maximum, a response according to the driver's intention can be obtained.
However, in an accelerating state where the driver opens the throttle valve by depressing the accelerator pedal, the chamber polyurethane in the intake pipe on the downstream side of the throttle valve becomes a delay element in the intake system, and the air in the intake pipe lags behind the opening of the throttle valve. Pressure increases. In particular, when the throttle valve is suddenly opened, the intake pipe internal pressure (absolute pressure) P _B does not increase immediately following the increase in the throttle valve opening θth, as shown in Figure 1 A and B, but lags behind this increase. increases. Furthermore, a detection delay of the intake pipe pressure detector (P _B sensor) itself is added to this delay in the increase in intake pipe pressure. In the conventional method described above, the amount of fuel supplied is set based on a reference value that depends on the absolute pressure in the intake pipe as well as the engine speed. As a result, the increase in the amount of fuel according to the reference value is delayed, and the amount of fuel supplied to the engine becomes insufficient, causing the air-fuel ratio of the air-fuel mixture to shift toward the lean side, making it impossible to obtain desired acceleration.

Furthermore, the opening operation period of the throttle valve (Fig. 1B)
The absolute pressure P _B in the intake pipe continues to increase even after the period from _time a ₁ to time _{a 3 shown} in FIG. If the increase in fuel supply amount during acceleration is determined according to the amount of change in throttle valve opening θth, the absolute pressure in the intake pipe will increase as described above.
The fuel increase was stopped before P _B had sufficiently increased, and the fuel was not increased for the period from point a ₃ to point a ₄ shown in Figure 1A, resulting in poor acceleration performance. affect.

Therefore, it is necessary to continue increasing the amount of fuel even while the intake pipe absolute pressure P _B is increasing, but the following points need to be taken into consideration when increasing the amount of fuel.

The deviation between the intake air amount and the detected intake pipe pressure due to the delay in increase and detection of the intake pipe pressure described above occurs when the throttle valve opening change amount Δθn reaches its maximum (i.e., ΔΔθn = 0), that is, at the end of acceleration. However, (i) the deviation decreases with a constant time constant after ΔΔθn < 0, and (ii) the period until the deviation becomes zero is the time when the amount of change Δθn is maximum (first It depends on the Δθn value at point _a2 in the figure.

Therefore, in the present invention, (a) the period in which the driver truly requests acceleration is the period in which the acceleration of the throttle valve opening is positive (ΔΔθn≧0); However, on the other hand, (b) the increase in intake pipe pressure has a time delay with respect to the change in throttle valve opening; The acceleration of continues to increase even after it changes from positive to negative, and (c)
The response delay in the intake pipe internal pressure corresponds to the amount of change Δθn in the throttle valve opening, that is, the above recognition (i) and (ii).
An object of the present invention is to increase the amount of intake air by following the throttle valve opening operation with good responsiveness during acceleration of an internal combustion engine, and by opening the throttle valve after acceleration. Provided is a fuel supply control method during acceleration of an internal combustion engine, in which the acceleration performance is improved over the entire acceleration stroke by increasing the amount of fuel according to the deviation between the intake pipe internal pressure rise delay and the detection delay. It is to be.

According to the first invention, in an electronic fuel supply control method for controlling the amount of fuel supplied to an internal combustion engine during acceleration using a predetermined control pulse signal, The opening degree of the throttle valve is detected, and the amount of change in the throttle valve opening degree between the current sampling signal generation time and the previous sampling signal generation time is set as the control parameter value, and the control parameter value at the current sampling signal generation time and the previous sampling signal generation time are set as control parameter values. (1) When the control parameter value at the time of the current sampling signal generation is larger than the predetermined value, and the current control parameter value is larger than the previous control parameter value, the control parameter value is compared with the control parameter value at each generation of the control pulse signal. An acceleration fuel increase value and a post-acceleration fuel increase period corresponding to the magnitude of the control parameter value when the current sampling signal is generated are set, and (2) the control parameter value when the current sampling signal is generated is greater than the predetermined value. In the meantime, from the point in time when the current control parameter value becomes smaller than the control parameter value, the acceleration fuel increase value is maintained over the post-acceleration fuel increase period that is set corresponding to the control parameter value immediately before that point. It is characterized by supplying a corresponding amount of fuel.

According to the second invention, in an electronic fuel supply control method for controlling the amount of fuel supplied to an internal combustion engine during acceleration using a predetermined control pulse signal, The opening degree of the throttle valve is detected, and the amount of change in the throttle valve opening degree between the current sampling signal generation time and the previous sampling signal generation time is set as the control parameter value, and the control parameter value at the current sampling signal generation time and the previous sampling signal generation time are set as control parameter values. (1) When the control parameter value at the time of the current sampling signal generation is larger than the predetermined value, and the current control parameter value is larger than the previous control parameter value, the control parameter value is compared with the control parameter value at each generation of the control pulse signal. (2) While the control parameter value when the current sampling signal is generated is larger than the predetermined value, the current control parameter value is set. From the point in time when the control parameter value becomes smaller than the previous control parameter value, an initial increase value corresponding to the magnitude of the control parameter value immediately before that point is set;
The present invention is characterized in that a predetermined value is subtracted from this initial increase value every time the control pulse signal is generated.

Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 2 is an overall configuration diagram of the device of the present invention,
Reference numeral 1 indicates, for example, a four-cylinder internal combustion engine, and the engine 1 is of a type consisting of four main combustion chambers and an auxiliary combustion chamber (both not shown) communicating with the main combustion chambers. An intake pipe 2 is connected to the engine 1, and the intake pipe 2 includes a main intake pipe communicating with each main combustion chamber and a sub-intake pipe (both not shown) communicating with each sub-combustion chamber. A throttle body 3 is provided in the middle of the intake pipe 2, and a main throttle valve and a sub-throttle valve (both not shown) disposed inside the main intake pipe and a sub-intake pipe, respectively, are provided in conjunction with each other. A throttle valve opening sensor 4 is connected to the main throttle valve to convert the valve opening of the main throttle valve into an electrical signal and send it to an electronic control unit (hereinafter referred to as "ECU") 5.

A fuel injection device 6 is provided in the intake pipe 2 between the engine 1 and the throttle body 3. This fuel injection device 6 consists of a main injector and a sub-injector (both not shown).The main injector is located in the main intake pipe slightly upstream of the intake valve (not shown) for each cylinder, and the sub-injector is located in the sub-intake pipe. These throttle valves are common to each cylinder and are provided slightly downstream of the sub-throttle valve. The fuel injection device 6 is connected to a fuel pump (not shown). Main injector and sub injector are ECU5
The fuel injection valve opening time is controlled by a signal from the ECU 5.

On the other hand, an absolute pressure sensor 8 is provided immediately downstream of the main throttle valve of the throttle body 3 via a pipe 7, and an absolute pressure signal converted into an electrical signal by the absolute pressure sensor 8 is sent to the ECU 5.
sent to. Also, downstream of it is an intake air temperature sensor 9.
is attached, and this intake pipe sensor 9 also converts the intake air temperature into an electrical signal and sends it to the ECU 5.

The main body of the engine 1 is provided with an engine water temperature sensor 10, which is made of a thermistor or the like, and is inserted into the circumferential wall of the engine cylinder filled with cooling water, and supplies its detected water temperature signal to the ECU 5.

An engine rotation speed sensor (hereinafter referred to as "Ne sensor") 11 and a cylinder discrimination sensor 12 are installed around the camshaft or crankshaft (not shown) of the engine, and the former 11 is a TDC signal, that is, 180 degrees of the engine crankshaft. The latter 12 outputs one pulse each at a predetermined crank angle position of a specific cylinder at a predetermined crank angle position for each rotation, and these pulses are sent to the ECU 5.

A three-way catalyst 14 is arranged in the exhaust pipe 13 of the engine 1, and performs a purifying action on HC, CO, and NOx components in the exhaust gas. On the upstream side of this three-way catalyst 14,
An O ₂ sensor 15 is inserted into the exhaust pipe 13 , and this sensor 15 detects the oxygen concentration in the exhaust gas and supplies the detected value signal to the ECU 5 .

Further, a sensor 16 for detecting atmospheric pressure and an engine starter switch 17 are connected to the ECU 5, and the ECU 5 is supplied with a detected value signal from the sensor 16 and a starter switch ON/OFF state signal.

Next, the details of the operation of the electronic fuel injection control device of the present invention having the above-mentioned configuration will be explained in detail in the first section described above.
This will be explained with reference to FIG. 2, and FIGS. 3 to 10.

First, FIG. 3 shows the air-fuel ratio control of the present invention, that is,
This is a block diaphragm that shows the overall program configuration of the control contents of the main and sub-injector valve opening times T _OUTM and T _OUTS in the ECU 5. It consists of a main program 1 and a sub-program 2, and the main program 1 is based on the engine speed Ne.
The subprogram 2 performs control in synchronization with the TDC signal and consists of a starting control subroutine 3 and a basic control program 4. On the other hand, the subprogram 2 consists of an asynchronous control subroutine 5 when not synchronized with the TDC signal.

The basic calculation formula in the starting control subroutine 3 is expressed as T _OUTM = Ti _CRM × K _Ne + (Tv + ΔTv) (1) T _OUTS = Ti _CRS × K _Ne + Tv (2). Here, Ti _CRM and Ti _CRS are reference values for the valve opening times of the main and sub-injectors, respectively, and are determined by Ti _CRM and Ti _CRS tables 6 and 7, respectively. K _Ne is a correction coefficient at the time of starting specified by the rotational speed Ne, and is determined by the K _Ne table 8. Tv is a constant for adjusting the valve opening time to increase or decrease according to changes in battery voltage.
It is determined from Table 9, and ΔTv is added to the Tv for the sub-injector for the main injector according to the operating characteristics of the injector due to the difference in structure.

Also, the basic calculation formula in basic control program 4 is T _OUTM = (Ti _M − T _DEC ) × (K _TA・K _TW・K _AFC・K _PA・K _AST・K _WOT・K _O2・K _LS ) +T _ACC × (K _TA・K _TWT・K _AFC・K _PA・K _AST ) + (Tv + ΔTv) …(3) T _OUTS = (Ti _S − T _DEC ) × (K _TA・K _TW・K _AST・K _PA ) + Tv … (4) is expressed as. Here, Ti _M and Ti _S are reference values for the valve opening times of the main and sub-injectors, respectively, and are calculated from the basic Ti map 10, respectively. T _DEC and T _ACC according to the present invention are constants during deceleration and acceleration, respectively, and the details are determined by the acceleration and deceleration subroutine 11 described later. Various coefficients such as K _TA , K _TW . . . are calculated by respective tables and subroutines 12. K _{T A}
is the intake air temperature correction coefficient, calculated from the table based on the actual intake air temperature, and K _TW is the actual engine water temperature.
T _W is the fuel increase coefficient determined from the table, K _AFC is the fuel increase coefficient after fuel cut determined by the subroutine, K _PA is the atmospheric pressure correction coefficient determined from the table according to the actual atmospheric pressure, K _AST is the post-start fuel increase coefficient determined by the subroutine, K _WOT is a constant and is the enrichment coefficient of the air-fuel mixture when the throttle valve is fully opened, and K _O2 is determined by the subroutine according to the actual oxygen concentration in the exhaust gas. The obtained O ₂ feedback correction coefficient, _KLS , is a constant and is a lean coefficient of the air-fuel mixture during lean/stoichiometric operation. Stoiki is
Stoichiometric is an abbreviation for stoichiometric amount, or stoichiometric air-fuel ratio.

On the other hand, the calculation formula of the asynchronous control subroutine 5 for the valve opening time T _MA of the main injector that is not synchronized with the TDC signal is expressed as T _MA = Ti _A ×K _TWT ·K _AST + (Tv + ΔTv) (5). Here, Ti _A is a fuel increase reference value during acceleration control that is asynchronous during acceleration, that is, not synchronized with the TDC signal, and is determined from the Ti _A table 13. K _TWT is the water temperature increase coefficient K _TW shown in Table 1.
Synchronous acceleration obtained from 4 and calculated based on it,
This is the fuel increase coefficient after acceleration and during asynchronous acceleration.

Figure 4 shows the cylinder discrimination signal and TDC signal input to the ECU 5, and the main signal output from the ECU 5.
This is a timing chart showing the relationship between the sub-injector drive signal and the pulse of the cylinder discrimination signal _S1 .
S ₁ a is inputted once every 720° of the engine crank angle, and in parallel, pulses S _{2 a} - S _{2 e of the TDC signal S 2} are inputted once every 180° of the engine crank angle.
Each cylinder's main injector drive signal S ₃ − is inputted pulse by pulse, and the relationship between these two signals is
The output timing of _S6 is set. That is, the first TDC signal pulse S ₂ a outputs the main injector drive signal S ₃ for the first cylinder, and the second TDC
With the signal pulse S ₂ b, the main injector drive signal S ₄ of the third cylinder is output, with the third pulse S ₂ c, the drive signal S ₅ of the fourth cylinder is output, and with the fourth pulse S ₂ d, the second cylinder is output. The cylinder drive signal _S6 is
Output sequentially. In addition, the sub-injector drive signal _S7 is applied every time each TDC signal pulse is input, that is,
One pulse is generated for every 180° of crank angle. still,
Pulses S ₂ a, S ₂ b of the TDC signal are set to occur 60 degrees earlier than the top dead center of the piston in the cylinder, and there is a delay due to calculation time in the ECU 5, and the intake air before the top dead center The time lag between when the air-fuel mixture is generated by opening the valve and operating the injector until the air-fuel mixture is sucked into the cylinder is absorbed in advance.

FIG. 5 shows a flowchart of the pre-air main program 1 when controlling the valve opening time in synchronization with the TDC signal in the ECU 5, and the entire program consists of an input signal processing block, a basic control block, and a starting control block. First, in the input signal processing block, when the engine ignition switch is turned on, the CPU in the ECU 5 is initialized (step 1), and a TDC signal is input when the engine is started (step 2). Then all the basic analog values are atmospheric pressure P _A , absolute pressure P _B , from each sensor.
Engine water temperature T _W , atmospheric pressure T _A , battery voltage V,
Throttle valve opening θth, _O2 sensor output voltage value
The on/off status of Vo ₂ and the starter switch 17 is read into the ECU 5, and the necessary values are stored (step 3). Next, the elapsed time from the first TDC signal to the next TDC signal is counted, and based on that value, the engine rotation speed Ne is calculated and stored in the ECU 5 (step 4). Next, in the basic control block, it is determined based on the calculated value of Ne whether the engine speed is less than or equal to the cranking speed (starting speed) (step 5). If the answer is affirmative (Yes), the engine is sent to the startup control subroutine of the startup control block, and Ti _CRM and Ti _CRS are determined based on the engine coolant temperature T _W using the Ti _CRM table and Ti _CRS table (Step 6). , and a correction coefficient K _Ne of Ne is determined using a K _Ne table (step 7). and,
The battery voltage correction constant Tv is determined from the Tv table (step 8), and each value is inserted into the above equations (1) and (2) to calculate T _OUTM and T _OUTS (step 9).

Also, if the answer is no in step 5,
If so, it is determined whether or not the engine is in a state that requires a fuel cut (step 10), and if the answer is affirmative (Yes), the values of T _OUTM and T _OUTS are both set to zero and a fuel cut is performed ( Step 11).

On the other hand, if the answer is determined to be No in step 10, each correction coefficient K _TA , K _TW , K _AFC ,
K _PA , K _AST , K _WOT , K _O2 , K _LS , K _TWT , etc. and correction constants T _DEC , T _ACC , Tv, ΔTv are calculated (step 12). These correction coefficients and constants are subroutines,
These are determined by a table or the like.

Next, a predetermined corresponding map is selected according to each data such as the rotational speed Ne, absolute pressure P _B, etc., and Ti _M and Ti _S are determined based on the map (step 13). Therefore, based on the correction coefficient value, correction constant value, and reference value obtained in steps 12 and 13 above, the previous formula (3),
Calculate T _OUTM and T _OUTS using (4) (step 14).
Then, the main and sub-injectors are operated respectively based on the values of T _OUTM and T _OUTS obtained in this way (step 15).

As mentioned above, in addition to controlling the valve opening times of the main and sub-injectors in synchronization with the TDC signal, the main injector is controlled in synchronization with a pulse train that is not synchronized with the TDC signal but has a fixed time interval. Although asynchronous control is performed, detailed explanation thereof will be omitted.

Next, a subroutine for calculating the acceleration fuel increase constant T _ACC and deceleration fuel decrease constant T _DEC in the valve opening time control described above will be described.

FIG. 6 shows a flowchart of a subroutine for calculating the acceleration and post-acceleration fuel increase constants T _ACC and T _PACC and the deceleration fuel decrease constant T _DEC under control synchronized with the TDC signal.

First, when each pulse of the TDC signal is input, the throttle valve opening value θn is read (step 1). Next, the value θn-1 of the throttle valve opening in the previous loop is retrieved from the memory (step 2), and the value θn-1 is retrieved from the memory (step 2).
The difference Δθn between θ(n-1) is the predetermined synchronous acceleration determination value G ⁺
(Step 3), and if the answer is affirmative (Yes), reset the number of pulses N _DEC of a deceleration ignoring counter, which will be described later, to a predetermined number of pulses N _DEC (Step 4). It is determined whether the difference ΔΔθn between the above difference Δθn and the difference Δθn−1 in the previous loop (hereinafter this value is referred to as "acceleration change amount") is 0 or positive (step 5), and if Yes acceleration,
If No, it is determined that it is after acceleration.
That is, as shown in Fig. 1B, the acceleration change amount ΔΔθn is differentiated twice with respect to the throttle valve opening θn, and the inflection point of the differential curve (Fig. 1B
This method determines whether the engine is accelerating or after accelerating based on the direction of change in the throttle valve opening (point a ₂ ). If it is determined in step 5 that it is an acceleration, the number of post-acceleration fuel increase pulses _N2 corresponding to the amount of change Δθn is set as the count number N _PACC in the post-acceleration counter (step 6). Figures 7a and 7b respectively show the relationship between the amount of change in throttle valve opening Δθn and the fuel increase constant T _ACC during acceleration, and the relationship between the count number N _PACC of the post-acceleration counter and the fuel increase constant T _PACC after acceleration. This is a table showing each relationship. In Fig. 7a, the fuel increase constant during acceleration T _ACC n corresponding to the amount of change Δθn is determined, and in Fig. 7b, the corresponding post-acceleration fuel increase constant T _{PACC n} is determined. Find the number of fuel increase pulses _N2 . In other words, when the amount of change Δθn in the throttle valve opening is large, the increase value after acceleration is also large, and the count number N _PACC after acceleration is also increased in order to maintain the increase time for a long time. The number N _PACC is also made small.

At the same time as step 6 above, the increase value T _ACC during acceleration is calculated in step 7a by the amount of change Δθn in the throttle valve opening.
Determine from the table shown in the figure (step 7). Then, the calculated T _ACC value is set in the basic equation, and the fuel reduction constant T _DEC during deceleration is set to 0 (step 8).

On the other hand, if the acceleration change amount ΔΔθn is smaller than 0 in step 5, it is determined whether the post-acceleration count number N _PACC set in step 6 is larger than 0 (step 9). The initial value of the post-acceleration count number N _PACC is set in step 6 above in response to the change amount Δθn of the throttle valve opening immediately before ΔΔθn<0, that is, the maximum value of Δθn during acceleration. If the answer is yes, subtract 1 from the above count number N _PACC (step
10), based on the N _PACC −1 obtained in this way, the seventh
The increase value T _PACC after acceleration is calculated from the table shown in Figure b (step 11), and the calculated T _PACC is set in the basic equation as T _ACC through step 8, and T _DEC is set to 0. Further, if it is determined in step 9 that the post-acceleration count number N _PACC is less than or equal to 0, both T _ACC and T _DEC are set to 0 (step 12).

On the other hand, if the amount of change Δθn is smaller than the predetermined value G ⁺ in step 3, it is determined whether or not Δθn is smaller than a predetermined synchronous deceleration determination value G ^- (step 13), and the answer is If the answer is No, it is assumed that the vehicle is cruising, and the process moves to step 9. If the answer is yes, it is determined whether deceleration is being ignored (step 14).
In other words, according to the present invention, even if the amount of change Δθn in the throttle valve opening is smaller than the predetermined value G ^- , deceleration is not determined until the number of TDC signal pulse counts exceeds a certain number of pulses N _DEC 〓. , it is treated as deceleration being ignored. Specifically, in step 14, it is determined whether the number of pulses N _DEC in the deceleration ignoring counter that was reset to a predetermined value N _DEC in step 4 is greater than 0, and if so, the pulse is Subtract 1 from the number N _DEC (step 15) and proceed to step 9. If N _DEC is less than 0 in step 14, the post-acceleration count N _PACC is set to 0 (step 16), and the fuel reduction constant T _DEC during deceleration is calculated (step 17). Then, the determined weight loss constant T _DEC is set in the basic equation, and T _ACC is set to 0 (step 18).

In the above subroutine, if acceleration is determined in step 5, T _PACC of the previous loop is
is canceled, but T _PACC and T _ACC may be compared and the larger value may be used.

8 and 9 show the internal configuration of the ECU 5 shown in FIG. 2, which controls the injection valve opening time based on equation (3),
FIG. 2 is a circuit diagram showing in particular the acceleration increase calculation circuit portion in detail.

First, Figure 8 shows the entire internal configuration of the ECU 5, and includes the intake pipe absolute pressure P _B (ABS) sensor 8, engine water temperature T _W sensor 10, intake air temperature T _A sensor 9, and throttle valve opening shown in Figure 2. Sensor 4 is A/D respectively
It is connected via a converter 505 to the input sides of an absolute pressure PB value register 507, an engine water temperature TW value register 508, an intake air temperature TA value register 506, and a throttle valve opening degree θTH value register 509. PB value register 507, TW value register 5
08 and each output side of the TA value register 506 is basically
Ti calculation control circuit 510 and various coefficient calculation circuit 51
1 and the output side of the θTH value register 509 are a various coefficient calculation circuit 511 and a deceleration amount calculation circuit 51.
2 and the respective input sides of the acceleration increase calculation circuit 513. The engine speed N _E sensor 11 in FIG. 2 is connected to the input side of a sequence clock generation circuit 502 via a one-shot circuit 501, and the output terminals of the sequence clock generation circuit 502 are connected to an NE measurement counter 504 and an NE value. It is connected to each input terminal of a register 503, a subtraction circuit 519, an addition circuit 521, and an acceleration increase calculation circuit 513, which will be described later. A reference clock generator 514 is connected to the input side of the NE measurement counter 504, and the output side is connected to the input side of the NE value register 503. The output side of the NE value register 503 is the basic Ti
It is connected to each input side of the calculation control circuit 510 and the various coefficient calculation circuit 511, respectively. The subtraction circuit 5
The input terminal 519a of No. 19 is connected to the output side of the basic Ti calculation control circuit 510, the input terminal 519b is connected to the output side of the deceleration loss calculation circuit 512, and the output terminal 519c is connected to the input terminal 52 of the multiplication circuit 520.
Connected to 0a. The input terminal 520b of the multiplication circuit 520 is connected to one output terminal of the various coefficient calculation circuit 511, and the output terminal 520c is connected to the input terminal 521a of the addition circuit 521. The input terminals 515a and 515b of the multiplication circuit 515 are the other output terminals of the various coefficient calculation circuit 511 and the acceleration increase calculation circuit 51.
The output terminal 515c is connected to the input terminal 5 of the adder circuit 521, respectively.
21b. Acceleration increase calculation circuit 51
The output terminal 513b of No. 3 is the deceleration amount calculation circuit 512.
The output terminal 521c of the adder circuit 521 connected to the input side of the T _OUT value register 522 and the T _OUT
It is connected to the injection valve 6 of FIG. 2 via a value control circuit 523.

Next, the operation of the circuit configured as described above will be explained. The TDC signal of the engine rotation speed sensor 11 in FIG. 2 is supplied to a one-shot circuit 501 which constitutes a waveform shaping circuit together with a sequence clock generating circuit 502 at the next stage. The one-shot circuit 501 generates an output signal _S0 for each TDC signal, and the signal _S0 activates a sequence clock generating circuit 502 to sequentially generate clock signals CP0 _-CP5 . FIG. 10 shows a timing chart of the output clock signal of the sequence clock generating circuit 502, and each time the output signal _S0 from the one-shot circuit 501 is input, clock signals CP0 _{to CP5} are generated in sequence. The clock signal CP ₀ is supplied to the rotational speed NE value register 503 and the reference clock generator 50
The immediately preceding count value of the rotation number counter 504 that counts the reference clock pulses from 9 is set in the NE value register 503. Clock signal CP ₁ is then applied to revolution counter 504 to reset the previous count value of the counter to signal 0. Therefore, the engine rotation speed Ne is measured as the number counted between the pulses of the TDC signal, and the measured rotation speed Ne is stored in the rotation speed NE value register 503.
Stored in The clock signals CP ₀ to CP ₅ are supplied to an acceleration increase calculation circuit 513, which will be described later, and are used as sampling signals.

In parallel with this, the throttle valve opening sensor 4,
The output signals of the intake air temperature sensor 9, absolute pressure sensor 8, and engine water temperature sensor 10 are supplied to the A/D converter 505 and converted into digital signals, and are then input to the throttle valve opening θTH value register 509 and the intake air temperature TA value, respectively. Register 506, absolute pressure
PB value register 507 and engine water temperature TW
A value register 508 is provided.

The basic Ti calculation control circuit 510 includes an absolute pressure PB value register 507 and an engine water temperature TW value register 50.
8. Calculate the basic valve opening time of the main injector according to the stored values supplied from the intake air temperature TA value register 506 and the engine speed NE value register 503, and send this calculated value Ti to the input terminal 519a of the subtraction circuit 519. Supplied as value M ₁ .

The various coefficient calculation circuit 511 includes an absolute pressure PB value register 507, an engine water temperature TW value register 508, an intake air temperature TA value register 506, and an engine rotation speed NE.
According to the stored values supplied from the value register 503 and the throttle valve opening θTH value register 509, the various coefficients K _TA , KT _W . Each of the values is input to the input terminal 520b of the multiplication circuit 520 and the multiplication circuit 515.
are supplied as values B ₁ and A ₂ to input terminals 515a of , respectively.

The deceleration loss calculation circuit 512 calculates the deceleration loss value T _DEC shown in step 17 of FIG. 6 based on the stored value from the throttle valve opening θTH value register 509 and the DEC signal indicating the deceleration state from the acceleration increase calculation circuit 513, which will be described later. is calculated, and this calculated value is supplied to the input terminal 519b of the subtraction circuit 519 as the value _N1 . Note that when the throttle valve opening change value Δθn is greater than or equal to the predetermined value G ⁻ (Δθn≧G ⁻ ), the reduction value T _DEC set to zero is supplied to the subtraction circuit 519 .

The acceleration increase calculation circuit 513 operates based on the stored value θn from the throttle valve opening θTH value register 509 and the clock signals CP _{0 to 5} from the sequence clock generation circuit 502, as will be described in detail later in FIG. The acceleration increase value T _ACC is calculated according to the procedure described above, and this calculated value T _ACC is supplied to the input terminal 515b of the multiplication circuit 515 as the value B ₂ . The multiplier circuit 515 multiplies the value A ₂ and the value B ₂ supplied to the input terminals 515a and 515b to obtain the multiplied value A ₂
×B _{2 ,} that is, the acceleration increase value corrected by the intake temperature correction coefficient K _TA , the atmospheric pressure correction coefficient K _PA , etc. as shown in equation (3) is supplied to the input terminal 521b of the adding circuit 521 as the value N ₂ . Incidentally, at times other than acceleration and fuel increase after acceleration, the acceleration increase calculation circuit 513
The acceleration increase value T _ACC output from is set to zero,
At this time, the value N ₂ supplied to the input terminal 521b of the adder circuit 521 also becomes zero.

The subtraction circuit 519 subtracts the values M ₁ and N ₁ and obtains this calculated value (M ₁ - N ₁ ), that is, (Ti _M -
T _DEC ) value is supplied to the input terminal 520a of the multiplication circuit 520 as the value _A1 . The multiplication circuit 520 multiplies the above calculated value (Ti _M −T _DEC ) by various coefficients (A ₁ ×
B ₁ ), the addition circuit 521 further adds the acceleration increase value corrected by the correction coefficient, and stores this calculated value (M ₂ +N ₂ ), that is, the T _OUT value of equation (3), in the T _OUT value register 522. supply

The T _OUT value control circuit 523 is connected to the T _OUT value register 52
Injector 6 based on the control value T _OUT supplied from 2
A control signal to open the injection valve 6 is supplied to the injection valve 6.

FIG. 9 is a circuit diagram showing in detail the internal configuration of the acceleration increase calculation circuit 513 of FIG. 8.

Throttle valve opening θTH value register 5 in Figure 8
09 are connected to the subtraction circuit 526 and the input terminals 526a and 525a of the θn _-1 register 525, respectively. The output terminal 525b of the θn _-1 register 525 is connected to the input terminal 526b of the subtraction circuit, and the output terminal 526c of the arithmetic circuit is connected to the input terminal 527a of the Δθn register 527.
The output terminal 527b of the Δθn register is the acceleration increase T _ACC
Value memory 537 and post-acceleration count N _PACC value memory 5
30, and the comparison circuits 529, 531, 541 and the Δθn _-1 register 52.
8 input terminals 529a, 531a, 541a, and 528a, respectively. This accelerated increase
The output of the T _ACC value memory 537 is connected to the input terminal of the AND circuit 536, the input terminal 529b of the comparison circuit 529 is connected to the output terminal 528b of the Δθn _-1 register 528, and the output terminal 529c is
It is connected to one input terminal of AND circuit 534 and also connected to one input terminal of each of AND circuits 533 and 553 via inverter 547 . Input terminal 53 of comparison circuit 531
A G ⁺ value memory 532a is connected to 1b, and an output terminal 531c is connected to the other input terminal of AND circuits 533 and 534, respectively, and is also connected to a data load terminal L of a down counter 542. The output side of the AND circuit 533 is the OR circuit 5
51, respectively. The output side of AND circuit 534 is connected to one input terminal of AND circuits 535 and 536, respectively, and to one input terminal of AND circuit 549 via inverter 552.

The G ^- value memory 532b is connected to the input terminal 541b of the comparator circuit 541, and the output terminal 541c is
The output terminal 5 is connected to the other input side of the AND circuit 553.
41d are connected to one input terminal of each of AND circuits 544 and 545, respectively. The output side of this AND circuit 553 is connected to the input side of the OR circuit 551. An N _DEC0 value memory 550 is connected to the input terminal 542a of the down counter 542,
The borrow output terminal of the down counter 542 is
via AND circuit 545 and inverter 534
They are respectively connected to the other input terminals of the AND circuit 544. The output side of the AND circuit 545 is connected to the input side of the OR circuit 551 and one input terminal of the AND circuit 546, and the output side of the AND circuit 544 is connected to one input terminal of the AND circuit 548. It is connected to the input side of the deceleration loss calculation circuit 512. The other input terminal of the AND circuit 546 is connected to the output terminal group of the sequence clock generation circuit 502 shown in FIG. 8, and the output side of the AND circuit 546 is connected to the clock terminal CK of the down counter 542.

The other input terminals of the AND circuits 535 and 548 are both connected to the output terminal group of the sequence clock circuit 502 in FIG. 8, and the output sides are the data load terminal L and clear terminal of the down counter 538, respectively.
Connected to CL. Also, N _PACC value memory 53
The output side of 0 is the data input terminal of the down counter.
Connected to D _IN . The data output terminal D _OUT of the down counter is connected to the input side of the T _PACC value memory 539 . Further, the borrow output terminal of the down counter 538 is connected to the AND circuits 554 and 555.
are input to one terminal of each. The output side of the T _PACC value memory 539 is connected to the input side of the AND circuit 555. The output side of OR circuit 551 is
They are connected to the other input sides of AND circuits 555 and 554, respectively. One more AND circuit 554
One input side is connected to a group of output terminals of sequence clock generation circuit 502 shown in FIG. 8, and an output side of AND circuit 554 is connected to clock terminal CK of down counter 538. The output side of AND circuit 555 is connected to the other input side of AND circuit 549. The output sides of AND circuits 536 and 549 are connected to the input side of the OR circuit 540.
The output of circuit 540 is connected to the input terminal of T _ACC value register 556 . The output terminal group of the sequential clock generation circuit 502 shown in FIG. 8 is connected to this register, and the T _ACC value register 5
The output side of 56 is connected to the input terminal 515b of multiplication circuit 515 in FIG.

Next, the operation of the circuit configured as described above will be explained.

The throttle valve opening signal value θn from the θTH value register 509 in FIG. 8 is supplied to the input terminal 526a of the subtraction circuit 526 as a value _M3 (step 1 in FIG. 6). The θn _-1 register 525 stores the throttle valve opening signal value θn _-1 that was input at the timing of application of the clock signal CP ₅ during the previous control loop, and this stored value is input to the input terminal 526b of the subtraction circuit 526. is supplied as the value _N3 (step 2 in FIG. 6). The subtraction circuit 526 subtracts the value from the value _M3 .
_N3 is subtracted, and this calculated value ( _M3 - _N3 ), that is, the Δθn (=θn-θn _-1 ) value, is supplied to the Δθn register 527 and stored at the timing of application of the clock signal _CP0 .

The T _ACC value memory 537 stores a plurality of _acceleration increase values T _ACC corresponding to the throttle valve opening change value Δθ based on FIG. Acceleration increase value T _ACC corresponding to valve opening change value Δθn
n is read out, and this read value T _ACC n is applied to the AND circuit 53.
6.

N _PACC value memory 530 contains FIGS. 7a and 7b.
A plurality of post-acceleration count values N _PACC corresponding to the throttle valve opening change value Δθn shown in the figure are stored,
N _PACC value memory 530 is the Δθn register 527
_The post-acceleration count value _n2 corresponding to the throttle valve opening change value Δθn from
Supply to D _IN .

The T _ACC value memory 537 and the N _PACC value memory 530 store a plurality of stored values T _ACC and N PACC as described above.
For example, it may be a matrix memory in which N _PACC is read out corresponding to the throttle opening change value Δθn, or an acceleration increase value corresponding to the throttle opening change value Δθn based on a predetermined calculation formula. It may be an arithmetic circuit that calculates T _ACC and post-acceleration count value N _PACC .

The operation of down counters 538 and 542 used in this circuit will now be explained. The down counter has four input terminals and two output terminals. The initial value for counting down is input from the data input terminal D _IN . The input is performed while the data load terminal L is receiving a high level signal=1. The initial value set here is counted down by 1 each time the clock signal CK is input. The count value is output from the data output terminal D _OUT
A high level signal = 1 is output from the borrow terminal while the count value is not zero, and a low level signal = 1 is output from the borrow terminal when the count value is zero.
0 is output. When a signal is input to the clear terminal CL, the count value of the down counter becomes zero.
Note that the down counter 542 has a data output terminal.
D _OUT and clear terminal CL are not used.

The G ⁺ value memory 532a stores a predetermined synchronous acceleration determination value G ⁺ of the throttle valve opening explained in step 3 ^of FIG. Supplied as value N ₄ . The comparator circuit 531 compares the throttle valve opening change value Δθn supplied from the Δθn register 527 as the value _M4 to its input terminal 531a with the discrimination value G ⁺ (step 3 in FIG. 6),
When Δθn > G ⁺ (M ₄ > N ₄ ), that is, when it is determined that the engine is in an accelerating state, a high level is output from the output terminal 531c of the comparison circuit to the AND circuits 533, 534 and the data load terminal L of the down counter 542. Supply signal=1. When the determination result of the comparison circuit 531 is Δθn≦G ⁺ (M ₄ ≦N ₄ ), the comparison circuit 531 outputs a low level signal=0 from the output terminal 531c, contrary to the above.

The input terminal 529a of the comparison circuit 529 is also supplied with the throttle valve opening change value Δθn from the Δθn register 527 as the value _M5 , and the input terminal 529b of the comparison circuit is supplied with the change value Δθn from the Δθn _-1 register 528 at the time of the previous loop. The throttle valve opening change value Δθn _-1 is supplied as the value _N5 . This throttle valve opening change value Δθn _-1 was supplied from the Δθn register 527 to the Δθn _-1 register 528 at the timing when the clock signal CP ₅ was applied to the Δθn _-1 register 528 during the previous loop, and was stored in the Δθn -1 register 528. be. The comparison circuit 529 compares the current change value Δθn of the throttle valve opening with the previous change value Δθn _-1 (6th
In step 5 in the figure, when the current change value Δθn is greater than the previous change value Δθn _-1 or equal to zero (that is, M ₅ ≧N ₅ , ΔΔθn = Δθn - Δθn _-1 ≧0), the output of the comparison circuit 529 AND circuit 5 from terminal 529c
A high level signal=1 is supplied to the other input terminal of 34.

When a high level signal = 1 is supplied to each of the two input terminals of the AND circuit 534, that is, when the throttle valve opening change value is larger than the first predetermined value G ⁺ (Δθn>G ⁺ ), and the above-mentioned throttle When the second differential value ΔΔθn of the valve opening value is positive or zero (ΔΔθn≧
0), the AND circuit 534 outputs a high-level signal=1 to open the AND circuits 535 and 536. The developed AND circuit 536 is AND circuit 5
36, which is supplied to one input terminal of the
The acceleration increase value T _ACC n from the T _ACC value memory 537 is
The _{TACC value is stored in the TACC} value register 556 via the OR circuit 540 at the timing of the clock signal _CP4 .
It is supplied to the multiplication circuit 515 in the figure (step 8 in FIG. 6). On the other hand, the opened AND circuit 535 applies the clock signal CP ₂ supplied to the other input terminal to the data load terminal L of the down counter 538, and transfers the read value from the N _PACC value memory 530 to the down counter 538. The data is input to the down counter 538 from the data input terminal D _IN (step 6 in FIG. 6). Data input to the down counter 538 is performed for each TDC signal while the AND circuit 534 is open, that is, while the conditions Δθn>G ⁺ and ΔΔθn≧0 are satisfied, and the counted value after acceleration is
The data in the down counter 538 is updated as the initial value _n2 of N _PACC .

Next, in the comparison circuit 529, if the current change value Δθn is smaller than the previous change value Δθn _-1 (that is, M ₅ <N ₄ , ΔΔθn = Δθn − Δθn _-1 <0), the output of the comparison circuit 529 is at a low level. The signal becomes 0, and this low level signal closes the AND circuit 534, and is inverted by the inverter 547 to become a high level signal=1, and this high level signal is supplied to the AND circuit 533. AND circuit 533 is part 2
When a high level signal = 1 is input to two input terminals,
That is, when Δθn>G ⁺ and ΔΔθn<0, a high level signal=1 is supplied to the OR circuit 551. This high level signal=1 is supplied to one input of AND circuits 554 and 555 via an OR circuit 551. The other inputs of the AND circuits 554 and 555 are connected to the borrow terminal of the down counter 538, and since the value of the down counter 538 is _n2 , the output of the borrow terminal is at a high level. In addition, the clock terminal of the down counter 538
Clock signal CP ₃ to CK via AND circuit 554
is supplied, and each time the clock signal _CP3 is applied, the count value of the down counter 538 is subtracted by 1, and the post-acceleration count value N _PACC n is stored in the T _PACC value memory 539.
supply to. This counting by the down counter 538 is executed until the post-acceleration count value N _PACC n becomes zero or a high level signal=1 is input to the clear terminal CL of the down counter 538, which will be described later. still,
When a high level signal is input to the clear terminal CL of the down counter 538, the output value of the down counter 538 becomes zero.

The T _PACC value memory 539 has a plurality of post-acceleration increase values corresponding to the post-acceleration count value N _PACC shown in FIG. 7b.
T _PACC is stored, and the T _PACC value memory 539 is the post-acceleration count value N _PACC from the down counter 538.
The post-acceleration increase value T _PACC n corresponding to n is read out, and this read value T _PACC n is supplied to the input side of the AND circuit 549 . It should be noted that the T _PACC value memory 539 may also be a matrix memory like the T _ACC value memory 532, etc., and the post-acceleration increase value corresponding to the post-acceleration count value N _PACC is stored based on a predetermined arithmetic expression. It may be an arithmetic circuit that calculates T _PACC .

The borrow terminal of the down counter 538 indicates whether or not the post-acceleration count value N _PACC n is zero, and when the post-acceleration count value N _PACC n is not zero, it supplies a high level signal = 1 to the AND circuit 554 and Count value N _PACC
When n becomes zero, a low level signal = 0 is supplied to the AND circuit 554, and the AND circuit 554 is closed, thereby stopping the countdown of the down counter 538.

The conditions for opening the AND circuits 554 and 555 and supplying the above-mentioned post-acceleration increase value T _PACC to the multiplication circuit 515 in FIG _. One of the following must hold true. That is, the first condition is Δθn>
G ⁺ and ΔΔθn<0, and at this time, as mentioned above, the AND circuit 533 ORs the high level signal = 1.
AND circuits 554 and 555 via circuit 551
is supplied to open both AND circuits 554 and 555. The second condition is Δθn≦G ⁺ and Δθn≧
G ^- , at this time the engine is in a cruise state, and as will be described later, a high level signal = 1 is sent from the output terminal 541c of the comparison circuit 541 to the AND circuits 554 and 555 via the AND circuit 553 and the OR circuit 551. Supplied. The third condition is Δθn
<G ^- and the deceleration ignoring counter value N _DEC described later is not zero, and the output terminal 5 of the comparator circuit 541
41d and the output of the borrow terminal of the down counter 542 are both high level signals = 1.
via AND circuit 545 and OR circuit 551
High level signal = 1 in AND circuits 554 and 555
is supplied.

The G ^- value memory 532b is stored in step 13 of FIG.
A predetermined synchronous deceleration determination value G ^- of the throttle valve opening degree explained in 1 is stored, and this determination value G ^- is supplied to the input terminal 541b of the comparison circuit 541 as the value N ₆ . The comparison circuit 541 has an input terminal 541
The throttle valve opening change value Δθn from the Δθn register 527 supplied to a is compared with the above-mentioned discrimination value G ^- (step 13 in Fig. 6), and when Δθn≧G ^- (M ₆ ≧N ₆ ) High level signal at output terminal 541c =
1 and outputs a low level signal=0 to the output terminal 541d. When the comparison result in the comparison circuit 541 is Δθn<G ^- (M ₆ <N ₆ ), the comparison circuit 541 outputs a low level signal = 0 to the output terminal 541c and a high level signal to the output terminal 541d, contrary to the above. Outputs level signal=1.

N _DEC0 value memory 550 is stored in step 4 of FIG.
The predetermined initial value of the deceleration ignoring count value N _DEC shown in
N _DEC0 is stored, and this stored value is supplied to the data input terminal D _IN of the down counter 542. The down counter 542 is connected to the data load terminal L.
While the high level signal = 1 from the comparator circuit 531 is supplied to the clock terminal CK of the down counter 542, the data is constantly being updated.
Even if a clock signal is applied to the down counter, it does not start counting and the output of the borrow terminal of the down counter is held at a high level. When the output of the comparison circuit 531 is inverted from high level to low level, that is, Δθn
When ≦G ⁺ , the down counter 542 no longer updates data, so it starts counting, and each time a clock pulse CP ₁ is applied to the clock terminal CK, it decelerates and ignores the count value N _DEC to its initial value.
N Subtract 1 from _DEC0 . down counter 54
2 is the AND circuit 54 from the borrow terminal of the down counter while the deceleration ignored count value N _DEC is not zero.
5 and an inverter 543 with a high level signal=1.

When a high level signal = 1 is supplied to both of its two input terminals, that is, when Δθn<G ^- and the deceleration ignoring count value N _DEC is not zero, the AND circuit 545 connects the AND circuits 554 and 555 via the OR circuit 551. At the same time as supplying a high level signal = 1 to
A high level signal=1 is also supplied to the AND circuit 546 to open the AND circuit 546. Opened AND
Circuit 546 supplies clock signal CP ₁ to clock terminal CK of down counter 542 for each TDC signal.

While the output of the borrow terminal of the down counter 542 is at a high level, the inverter 543 supplies a low level signal = 0 to one input terminal of the AND circuit 544 to close the AND circuit 544, and outputs the output of the down counter 542. When becomes a low level, that is, the down counter 542 reaches a predetermined number of times N _DEC0
When the count reaches zero, the inverter 543 sends the inverted high level signal = 1 to the AND circuit 544.
is supplied to open the AND circuit 544. AND
When the circuit 544 is supplied with a high level signal=1 to both of its two input terminals, that is, Δθn<
When G ^- and the deceleration ignoring count value N _DEC is zero, a high level signal = 1 is output to the output side. In this way, even if the throttle valve is operated in the closing direction and the throttle valve is in a deceleration state (Δθn<G ^- ), it is not determined to be deceleration until the down counter 542 counts a predetermined number of times, and the deceleration is treated as being ignored. AND circuit 54
High level signal from 4 = 1 (DEC signal) is AND
The clock signal CP ₂ is supplied to the clear terminal CL of the down counter 538 by the circuit 548, and the down counter 538 outputs the counted value after acceleration.
Even if the N _PACC is being counted, the count value is cleared to zero (step 16 in Figure 6), and the 8th
It is also supplied to the deceleration loss calculation circuit 512 in the figure, and causes the circuit 512 to calculate the deceleration loss value T _DEC (step 18 in FIG. 6).

In the embodiment shown in FIG. 9, the sequence clock generating circuit 502 uses a clock signal generated in synchronization with the TDC signal.
It may also be a clock signal of a clock signal generation circuit that is not synchronized with the signal.

As detailed above, according to the first invention of the present application, the opening degree of the throttle valve provided in the intake passage is detected every time a predetermined sampling signal is generated, and The amount of change in the throttle valve opening over time is taken as the control parameter value, and the control parameter value when the current sampling signal is generated is compared with the control parameter value when the previous sampling signal is generated. Every time the control pulse signal occurs, the control parameter value is larger than the predetermined value, and the current control parameter value is larger than the previous control parameter value, the acceleration fuel amount is increased corresponding to the magnitude of the control parameter value when the current sampling signal is generated. (2) While the control parameter value at the time of the current sampling signal generation is greater than the predetermined value, from the time when the current control parameter value becomes smaller than the previous control parameter value, the corresponding control parameter value is set. A fuel amount corresponding to the acceleration fuel increase value is supplied over the post-acceleration fuel increase period that is set corresponding to the control parameter value immediately before the point in time.

Furthermore, according to the second invention of the present application, (1) when the control parameter value when the current sampling signal is generated is larger than a predetermined value, and the current control parameter value is larger than the previous control parameter value, the control pulse signal (2) While the control parameter value when the current sampling signal is generated is larger than the predetermined value,
From the time when the current control parameter value becomes smaller than the previous control parameter value, an initial increase value corresponding to the magnitude of the control parameter value immediately before that point is set, and from this initial increase value, every time the control pulse signal is generated. A predetermined value is subtracted from .

Therefore, with the configurations of the first and second aspects of the invention, an appropriate amount of increased fuel can be supplied to the engine in accordance with the amount of change in the throttle valve opening during acceleration when the amount of acceleration change in the throttle valve opening is positive; While ensuring the required acceleration responsiveness, after acceleration after the acceleration change amount turns negative, the fuel increase period according to the maximum change amount of the throttle valve opening during acceleration and/or the maximum change By supplying increased fuel to the engine with a fuel increase value corresponding to the amount of fuel, an amount that correctly corresponds to the deviation between the amount of intake air due to the opening of the throttle valve during acceleration and the delay in rising the pressure in the intake pipe and the delay in detection. By supplying fuel, it is possible to improve acceleration performance and drivability in the entire acceleration stroke from during acceleration to after acceleration.

[Brief explanation of drawings]

Figure 1 is a diagram explaining the relationship between the throttle valve opening and intake pipe absolute pressure during acceleration of an internal combustion engine.
2 is a block diagram of the entire fuel supply control system to which the method of the present invention is applied, and FIG. 3 is a diagram illustrating the main and sub-injectors in the ECU of FIG. 2. A block diagram of the entire program configuration for controlling the valve opening time T _OUTM and T _OUTS , Figure 4 is the ECU
cylinder discrimination signal and TDC signal input to the
A timing chart showing the relationship between the main and sub-injector drive signals output from the ECU,
Figure 5 is a flowchart of the main program for calculating the basic valve opening time T _OUTM and T _OUTS . Figure 6 is the calculation of the fuel increase coefficients T _ACC and T _PACC during acceleration and after acceleration, and the fuel decrease constant T _DEC during deceleration. The flowchart of the subroutine, Fig. 7, is a diagram explaining the calculation method of the fuel increase coefficient during acceleration T _ACC and the post-acceleration fuel increase coefficient T _PACC , and Fig. 7a shows the amount of change Δθ of the throttle valve opening and the fuel increase coefficient during acceleration. A table showing the relationship between the fuel increase coefficient T _ACC and FIG. 7b is a table showing the relationship between the post-acceleration count value N _PACC and the post-acceleration fuel increase coefficient T _PACC ,
Figure 8 is a circuit diagram showing the internal configuration of the ECU 5 in Figure 2, Figure 9 is a circuit diagram detailing the internal configuration of the acceleration increase calculation circuit in Figure 8, and Figure 10 is a circuit diagram showing the internal configuration of the ECU 5 in Figure 2. FIG. 3 is a diagram illustrating the order in which clock signals are generated. DESCRIPTION OF SYMBOLS 1... Internal combustion engine, 2... Intake passage, 3... Throttle valve, 4... Throttle valve opening sensor, 5... Electronic control unit (ECU), 6... Fuel injection valve, 11... Engine speed sensor, 502... Sequence clock Generation circuit, 521... Addition circuit, 5
23...T _OUT value control circuit, 525...θn _-1 register,
526...Subtraction circuit, 527...Δθn register, 52
8...Δθn _-1 register, 530...N _PACC value memory,
532...T _ACC value memory, 538...Down counter, 539...T _PACC value memory, 510...Basic Ti calculation circuit, 513...Acceleration increase calculation circuit.

Claims (1)

[Scope of Claims] 1. In an electronic fuel supply control method for controlling the amount of fuel supplied to an internal combustion engine during acceleration using a predetermined control pulse signal, a throttle valve provided in an intake passage is provided each time a predetermined sampling signal is generated. The amount of change in the throttle valve opening between the current sampling signal generation time and the previous sampling signal generation time is set as the control parameter value, and the control parameter value at the current sampling signal generation time and the previous sampling signal generation time are detected. (1) When the control parameter value at the time of the current sampling signal generation is larger than the predetermined value, and the current control parameter value is larger than the previous control parameter value, each time the control pulse signal is generated, An acceleration fuel increase value and a post-acceleration fuel increase period corresponding to the magnitude of the control parameter value when the current sampling signal is generated are set; (2) while the control parameter value when the current sampling signal is generated is greater than the predetermined value; From the point in time when the current control parameter value becomes smaller than the previous control parameter value, the control parameter value is adjusted according to the acceleration fuel increase value over the post-acceleration fuel increase period that is set corresponding to the control parameter value immediately before that point. A method for controlling fuel supply during acceleration of an internal combustion engine, characterized by supplying an amount of fuel. 2. In an electronic fuel supply control method that controls the amount of fuel supplied to an internal combustion engine during acceleration using a predetermined control pulse signal, the opening degree of a throttle valve provided in an intake passage is detected every time a predetermined sampling signal is generated. , the amount of change in throttle valve opening between the current sampling signal generation time and the previous sampling signal generation time is taken as the control parameter value, and the control parameter value at the current sampling signal generation time and the control parameter value at the previous sampling signal generation time are compared. (1) When the control parameter value when the current sampling signal is generated is larger than the predetermined value, and the current control parameter value is larger than the previous control parameter value, each time the control pulse signal is generated, the control parameter value when the current sampling signal is generated is An acceleration fuel increase value corresponding to the magnitude of the control parameter value is set, and (2) while the control parameter value at the time when the current sampling signal is generated is greater than the predetermined value, the control parameter value immediately before that time is the previous control parameter value. From the point in time when the control parameter value becomes smaller, an initial increase value corresponding to the magnitude of the control parameter value immediately before that point is set, and a predetermined value is subtracted from this initial increase value every time the control pulse signal is generated. A fuel supply control method during acceleration of an internal combustion engine. 3. The increase value in which a predetermined value is subtracted from the initial increase value every time the control pulse signal is generated is continued until the increase value after the gradual decrease reaches the set value. A method for controlling fuel supply during acceleration of an internal combustion engine.