JPH0451656B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for controlling the idle speed of an internal combustion engine, and particularly to a method for controlling the idle speed of an internal combustion engine, and in particular, suppresses changes in the engine speed when the electrical load on the internal combustion engine (hereinafter referred to as engine) decreases during idle speed control. , relates to an idle rotation speed control method with improved control accuracy.

Conventionally, for example, a target idle speed is set depending on the engine load condition, the difference between this target idle speed and the actual engine speed is detected, and the system is adjusted according to the size of the difference so that this difference becomes zero. An idle speed feedback control method is widely known in which auxiliary air is supplied to the engine to maintain the engine speed at a target idle speed.

For example, if a load such as a headlight or a radiator fan is added during such engine speed control, this load will directly increase the load on the engine, or the generator will be activated to charge the battery consumed by the electrical load. This increases the load on the engine and lowers the engine speed. To prevent such changes in engine speed,
The generator is determined to start or stop by detecting the on-off state of the electrical device, and simultaneously detects the on-off state of the electrical device before the influence of electrical load fluctuations appears as a change in engine speed. A method of increasing or decreasing the amount of air supplied to the engine has already been proposed by the applicant (Japanese Patent Application No. 1987-
No. 066928).

However, when the power required by an electrical device exceeds the generating capacity of the generator, the insufficient power is supplemented from the battery, so the load condition that should be reduced by turning off the electrical device and the actual There may be cases where the load condition of the engine does not correspond to the load condition of the engine. That is, for example, as shown in Fig. 1, when power is supplied from the battery to the electrical device and the output voltage V _B of the battery becomes exhausted below the predetermined voltage V _BEG (Sn in Fig. 1 b), the power generation starts. Even after the electrical equipment is turned off, the machine maintains full power generation to charge the battery, so even when the electrical equipment is turned off, the engine is still under load from the generator operation. Therefore, if the intake air is reduced immediately (Sn' in Figure 1c) when the electrical device turns off (Sn in Figure 1a), the engine will not have the amount of air to match the load. As a result, the engine speed suddenly decreases (dashed line in FIG. 1d). This sudden decrease in engine speed not only gives discomfort to the driver, but also delays charging of the battery, and there is a risk of engine stalling if the clutch is engaged when the engine speed suddenly decreases.

The first invention was made in view of the above points, and reduces the engine speed when the electrical device is turned off by supplying the engine with an amount of air corresponding to the load actually applied to the engine. The purpose is to avoid.

In order to achieve this object, the first invention includes at least one electrical device, a battery for supplying electric power to the electrical device, and a generator driven by the crankshaft of an internal combustion engine to control the amount of intake air. In the idle speed control method of controlling the idle speed of an internal combustion engine by a control valve to be adjusted, the on-off state of the at least one electrical device is detected, and the on-off state of the detected at least one electrical device is adjusted. Accordingly, the control valve increases or decreases the amount of intake air by a predetermined amount, detects the state of the generator immediately after the electric device is switched from on to off, An object of the present invention is to provide an idle rotation speed control method for an internal combustion engine, which prevents the predetermined amount of reduction control from being performed when it is determined that the engine is under load.

Next, the internal combustion engine is equipped with a fuel supply control device that detects the total amount of intake air including the above-mentioned auxiliary air and determines the amount of fuel to be supplied to the engine based on engine operating parameter values including at least the detected intake air amount value. In an engine, a sensor that detects the engine load based on the negative pressure in the intake pipe has a detection delay, so it cannot respond when the amount of auxiliary air changes suddenly.
In other words, the intake air amount detected when the auxiliary air amount suddenly decreases is smaller than the actual intake air amount, and the intake air amount detected when the auxiliary air amount suddenly decreases is larger than the actual intake air amount. The air-fuel mixture supplied to the engine may become lean or overrich, which may adversely affect engine operation.

In order to eliminate such problems, the amount of fuel supplied to the engine over a predetermined period of time is increased or decreased by a predetermined amount in response to the on-off signal of the electric device, and the air-fuel ratio is maintained even during the detection delay time of the sensor. A method of controlling fuel supply to maintain the optimum value has already been proposed by the present applicant (Japanese Patent Application No. 57-066042).

However, as mentioned above, even after the electrical device changes to the OFF state, if the output voltage V _B of the battery is below the predetermined voltage V _BEG , the auxiliary air amount immediately before the change is maintained, and in such a case, the fuel amount changes as described above. If the reduction correction is started in response to the generation of an off signal from the electric device, the air-fuel mixture may become leaner, which may adversely affect the operating state of the engine.

Therefore, the second invention aims to solve the above-mentioned problems, and in addition to the first invention, at least one
1 electric device, a battery that supplies power to the electric device, and a generator driven by the crankshaft of the internal combustion engine. In the idle rotation speed control method for controlling the rotation speed, an on-off state of the at least one electrical device is detected, and the suction is controlled by both control valves according to the detected on-off state of the at least one electrical device. controlling the amount of air to be increased or decreased by a predetermined amount, controlling the amount of fuel supplied to the internal combustion engine to be increased or decreased, detecting the state of the generator immediately after the electric device is switched from on to off, and controlling the amount of fuel supplied to the internal combustion engine; Provided is a method for controlling the idle speed of an internal combustion engine, characterized in that when it is determined that the internal combustion engine is under a high load, the intake air amount reduction control and the fuel amount reduction control are not performed. .

An embodiment of the control method of the present invention will be described below with reference to the drawings.

FIG. 2 is a block diagram schematically showing the entire engine speed control device for an internal combustion engine to which the method of the present invention is applied. Reference numeral 1 indicates, for example, a four-cylinder internal combustion engine. An intake passage (hereinafter referred to as "intake pipe") 3 to which an air cleaner 2 is attached is connected to an exhaust pipe 4. A throttle valve 5 is arranged in the middle of the intake pipe 3, and an air passage 8 that opens into the intake pipe 3 on the downstream side of the throttle valve 5 and communicates with the atmosphere is arranged. An air cleaner 7 is attached to the open end of the air passage 8 on the atmosphere side, and an auxiliary air amount control valve (hereinafter simply referred to as "control valve") 6 is disposed in the middle of the air passage 8. The control valve 6 is a normally closed solenoid valve, and is composed of a solenoid 6a and a valve 6b that opens the air passage 8 when the solenoid 6a is energized.
a stands for electronic control unit (hereinafter referred to as “ECU”)
9).

A fuel injection valve 10 is provided between the engine 1 of the intake pipe 3 and the opening 8a of the air passage 8, and this fuel injection valve 10 is connected to a fuel pump (not shown) and electrically connected to the ECU 9. It is connected.

A throttle valve opening sensor 11 is attached to the throttle valve 5, and a throttle valve opening sensor 11 is connected to the opening 8a of the air passage 8 of the intake pipe 3.
An intake pipe absolute pressure sensor 13 that communicates with the intake pipe 3 via a pipe 12 is installed on the downstream side, and an engine coolant temperature sensor 14 and an engine rotation angle position sensor 15 are installed on the engine 1 body, and each sensor is connected to the ECU 9. electrically connected.

Reference numerals 16, 17, and 18 are for example a first headlight, a radiator fan, a heater fan, etc.
Second and third electrical devices are shown, respectively. One terminal side of the headlight 16 is connected to a connection point 19a via a switch 16a and directly connected to the ECU, and the other terminal side is grounded. One terminal of each of the radiator fan 17 and the heater fan 18 is directly connected to the connection point 19a, and the other terminal of each is directly connected to the ECU 9 and grounded via switches 17a and 18a, respectively.

An alternator 20 is connected to the connection point 19a, and a battery output voltage detector 21 is also connected to the connection point 19a.
This voltage detector 21 is also connected to the ECU 9 and supplies a detected output voltage value signal of the battery 19 to the ECU 9. Further, a regulator 20a is connected in parallel to the generator 20,
Generator 2 according to the output voltage value V _B of battery 19.
It is designed to control a field current of 0.

The generator 20 is the output shaft of the engine 1 (not shown)
It is mechanically connected to the engine 1 and is driven by the engine 1. And each switch 16a, 17a, 18a
is in the closed (on) state and each electrical device 16,1
When power is supplied from the generator 20 to the electrical devices 16, 17, and 18, and the power required to operate each electrical device 16, 17, and 18 exceeds the generation capacity of the generator 20, the insufficient power is supplemented from the battery 19. be exposed. When the battery 19 is exhausted and the output voltage V _B of the battery 19 decreases to a predetermined voltage value V _BEG or less, the regulator 20 a is activated to increase the field current to the maximum rated current and bring the generator 20 into a full power generation state. Therefore, even if the switches 16a, 17a, and 18a are opened (off) while the battery 19 is exhausted, the load that causes the generator 20 to be in a full power generation state continues to be applied to the engine 1.

Throttle valve opening sensor 11, absolute pressure sensor 1
3. Engine operating state parameter signals from the cooling water temperature sensor 14 and engine rotation angle position sensor 15 as well as battery output value signals from the detector 21 are supplied to the ECU 9, and the ECU 9 receives the values of these engine operating state parameter signals and the first, The engine operating state and engine load state are determined based on the electrical load state signals from the second and third electrical devices 16, 17, and 18 and the signal from the detector 21, and the engine operating state and the engine load state are determined based on the determined states. The fuel supply amount, that is, the valve opening time of the fuel injection valve 10, and the auxiliary air amount, that is, the operating amount of the control valve 6, for example, the valve opening time of the control valve 6, are respectively calculated, and the fuel injection valve is adjusted according to each calculated value. 10 and control valve 6, respectively.

The solenoid 6a of the control valve 6 is energized for a valve opening time corresponding to the calculated value, and the valve 6b is opened to open the air passage 8, and a predetermined amount of air according to the valve opening time is supplied to the air passage 8 and the air passage 8. It is supplied to the engine 1 via the intake pipe 3.

The fuel injection valve 10 is opened for a valve opening time according to the above-mentioned calculated value to inject fuel into the intake pipe 3, and the injected fuel is mixed with the intake air so that a mixture with a predetermined air-fuel ratio is always supplied to the engine 1. It is now being supplied to

When the amount of auxiliary air is increased by lengthening the opening time of the control valve 6, the amount of air-fuel mixture supplied to the engine 1 increases, the engine output increases, and the engine speed increases. Conversely, if the opening time of the control valve 6 is shortened, the amount of air-fuel mixture to be supplied will decrease and the engine speed will decrease. By controlling the amount of auxiliary air, that is, the opening time of the control valve 6 in this way, the engine speed can be controlled. The opening time of the fuel injection valve 10 is determined by the electric device 16, as will be described in detail later.
This is due to a delay in detecting the amount of auxiliary air that has been increased or decreased due to the predetermined valve opening time being increased or decreased over a predetermined number of times after a predetermined time has elapsed from the time of input of each signal in accordance with the respective electrical load signals from 17 and 18. Excesses and deficiencies in the amount of fuel are corrected to supply the engine 1 with an amount of fuel that accurately corresponds to increases and decreases in the amount of auxiliary air.

Fig. 3 is a diagram showing the circuit configuration inside the ECU 9 shown in Fig. 2, and the engine rotation angle position sensor 1 shown in Fig. 2.
The output signal from 5 is waveform-shaped by a waveform shaping circuit 901, and then supplied to a central processing unit (hereinafter referred to as "CPU") 902 as a TDC signal.
It is also supplied to the Me counter 903. The Me counter 903 counts the time interval from the input of the previous TDC signal from the engine rotation angle position sensor 15 to the input of the current TDC signal, and its count value
Me is proportional to the reciprocal of the engine speed Ne. Me
Counter 903 supplies this count value Me to CPU 902 via data bus 904.

Detection signals from various sensors such as the throttle valve opening sensor 11, intake pipe absolute pressure sensor 13, water temperature sensor 14, etc. and the detection signal from the battery voltage detector 21 shown in FIG. After being modified, multiplexer 90
6 is sequentially supplied to the A/D converter 907. The A/D converter 907 is connected to each sensor 1 described above.
The detection signals from 1, 13, 14 and the detector 21 are sequentially converted into digital signals, and the digital signals are supplied to the CPU 902 via the data bus 904.

First, second and third electrical devices 1 shown in FIG.
Switches 16a and 17 of 6, 17, and 18, respectively.
The on-off signal from a, 18a is corrected to a predetermined voltage level by a level correction circuit 908, converted into a predetermined signal by a data input circuit 909, and supplied to the CPU 902 via a data bus 904.

The CPU 902 further provides a read-only memory (hereinafter referred to as "ROM") via a data bus 904.
910, random access memory (hereinafter referred to as "RAM") 911 and drive circuit 912,
913, RAM911 is connected to CPU9
Temporarily stores the calculation results etc. in 02, and stores it in ROM9.
10 stores control programs and the like executed by the CPU 902.

According to the control program stored in the ROM 910, the CPU 902 determines the engine operating state and engine load state according to the aforementioned various engine parameter signals and battery voltage value signal, and opens the control valve 6 that controls the amount of auxiliary air. The time, that is, the valve opening duty ratio _DOUT is calculated, and a control signal corresponding to this calculated value is supplied to the drive circuit 912.

For example, if the engine speed control is feedback control, this valve opening duty ratio D _OUT is a value calculated according to the difference between the target engine speed and the actual engine speed, and a value calculated according to the difference between the target engine speed and the actual engine speed, and the on-off of the electric devices 16, 17, 18. It is calculated as the sum of the value calculated based on the off state, that is, the magnitude of the electrical load (hereinafter referred to as "electrical load term").

The CPU 902 further calculates the fuel injection time T _OUT of the fuel injection valve 10 and sends a control signal based on this calculated value to the drive circuit 913 via the data bus 904.
supply to. The drive circuit 913 supplies the fuel injection valve 10 with a control signal that opens the fuel injection valve 10 according to the calculated value, and the drive circuit 912 supplies an on-off drive signal that turns the control valve 6 on and off to the control valve 6. supply to.

FIG. 4 is a flowchart of a calculation program for calculating the electrical load term D _Eo according to the first invention, among the control programs for the control valve 6 that are executed in the ECU 9 for each TDC signal. This electric load term D _Eo is a value corresponding to a correction amount for correcting the operating amount of the control valve 6, that is, the valve opening duty ratio.

When this D _Eo calculation program is called (step 1 in FIG. 4), first, the stored value of D _Eo is reset to zero (step 2). Next, it is determined whether the switch 16a of the first electric device 16 shown in FIG. 2 is in the on state (step 3), and if the determination is negative (No), the process proceeds to step 5. If the determination result in step 3 is affirmative (Yes), a predetermined amount D ₁ corresponding to the electrical load of the first electrical device 16 is added to the stored value of D _Eo , and this added value (D _Eo + D ₁ ) is set as the new D Set it as the memorized value of _Eo (step 4). Note that since D _Eo was reset to 0 in step 2, the new stored value of D _Eo in step 4 is equal to D ₁ .

Next, the on/off state of the switch 17a of the second electric device 17 is determined in the same manner as described above (step 5). If it is not on, the process proceeds to step 7, and if it is on, the stored value of D _Eo is set. 2 electrical equipment 17
A predetermined amount D ₂ corresponding to the electrical load is added, and this added value (D _Eo +D ₂ ) is set as a new stored value of D _Eo (step 6). Furthermore, in the same manner as described above, the on/off state of the switch 18a of the third electric device 18 is determined (step 7), and if it is not on, the process proceeds to step 9, and if it is on, the _third
A predetermined amount D ₃ corresponding to the electrical load of the electrical device 18 is added, this added value (D _Eo +D ₃ ) is set as a new stored value of D _Eo (step 8), and the process proceeds to step 9.

Next, it is determined whether the difference ΔD _Eo = D Eo − D _{Eo -1 between the D Eo-1} value calculated when the TDC signal was generated last time and the D _Eo value calculated in step ₈ this time is a negative value. (Step 9). This determination result is negative (No)
In the case of , that is, if the current electrical load term D _Eo is equal to or increased from the previous electrical load term D _Eo-1 , proceed to step 10 and set the flag η _IMFLG used in the T _AIC determination subroutine described later. It is determined whether the value of is 1 or not. If the determination result in step 10 is negative (No), that is, if η _IMFLG is not 1, proceed to step 11, set η _IMFLG = 0, and finish the execution of the program (step 15), and set the current valve opening duty. The ratio D _OUT is the current electrical load term D _Eo
Calculate using.

If the determination result in step 9 is positive (Yes),
That is, if the electrical load term D _Eo at this time is smaller than that at the previous time, or if the determination result in step 10 is affirmative (Yes), the process proceeds to step 12, and it is determined that the battery 19 is exhausted as described above. In order to determine whether the engine is under a load that causes the generator 20 to be in a full power generation state, it is determined whether the average value V _BX of the output voltage V _B of the battery 19, which will be described later, is smaller than a predetermined value V _BEG . . This average value V _BX is calculated, for example, in the V _BX calculation subroutine shown in FIG. 7 every time the TDC signal is generated. That is, the output voltage V _B of the battery 19 is detected by the voltage detector 21 (step
21), then in step 22 the average value of the battery voltage is
V _BX is calculated based on the detected value V _B. This calculation is performed, for example, using the following equation.

V _BXo = X/256V _Bo +256-X/256V _{BXo-1 Here} ,
is the average value found last time, and V _Bo is the current detected value of battery voltage.

The reason why the average value V _BX of the voltage detection value V _B is used as the value to be compared with the predetermined value V _BEG in step 12 of FIG. This is because the battery voltage value V _B cannot be detected, and the X value in the above equation is set based on the magnitude of the influence of these noises. Further, the predetermined value V _BEG is a preset value that is used as a criterion for determining whether or not the operation of the generator 20 applies a high load to the engine, as described above.

The determination result in step 12 in Figure 4 is negative (No).
In this case, that is, if the battery 19 is not exhausted, it is determined that there is no load on the engine to cause the generator 20 to generate full power, and the process proceeds to step 11 described above. If the determination result is affirmative (Yes), the current D _Eo value is reset to the previous D _Eo-1 value for the reason described later (step 13), and then the process proceeds to step 14 to calculate T _AIC , which will be described later. The value of the flag η _IMFLG used in the subroutine is set to 1, the current execution of the program is ended (step 15), and the current valve opening duty ratio D _OUT is set as the previous electrical load term D _o- Calculate using ₁ .

The reason why the current D _Eo value is set to the previous value D _Eo-1 in step 13 is because, for example, as shown in Figure 1, the electrical load on the engine is released when the switch of the electrical device is turned off. (Figure 1a)
Sn), if the average value V _BX of the output voltage of the battery 19 is smaller than the predetermined value V _BEG (Sn in Figure 1 b), the engine causes the generator 20 to be in full power generation mode even if the switch of the electrical device is turned off. This means that the load continues to be applied, and in this case, the intention is to maintain the valve opening duty ratio D _OUT at the previous _value without reducing it, as shown by the broken line in Figure 1c ( S _o-1 , Sn in Figure 1c). Then, until the output voltage value V _B of the battery 19 recovers and the average value V _BX reaches the predetermined value V _BEG , step 10 is performed for each TDC signal even if it is determined in step 9 that there is no reduction in the electrical load. Since the value of the flag _ηIMFLG is 1, the battery voltage is determined in step 12.
Therefore, the electric load term D _Eo is held at the value D _Eo-1 until the determination result in step 12 of FIG. 4 becomes negative (No). As a result, the engine speed Ne is maintained approximately at the target speed N _H as shown by the solid line in FIG. 1d, and the engine speed Ne does not suddenly decrease as shown by the broken line in FIG. 1c.

FIG. 6 is a diagram illustrating a method for increasing and decreasing the amount of fuel supplied to the engine 1 when loads such as electrical devices are turned on and off during engine speed control. For ease of explanation, each TDC signal is numbered in the order in which it occurs.
TDC signal is "TDC2 signal""TDC3signal" respectively...
During the period between the occurrence of the TDC19 signal and the occurrence of the TDC19 signal,
For example, a case will be described in which only the first electric device 16 is turned on and off.

Now, assume that the first electrical device 16 is turned on between the TDC4 signal and the TDC5 signal and turned off between the TDC10 signal and the TDC11 signal (FIG. 6b).
The ECU 9 detects the ON signal of the first electrical device 16 immediately after the signal of the TDC 5 and increases the amount of auxiliary air by a predetermined amount corresponding to the electrical load of the first electrical device 16, that is, the opening of the control valve 6. Valve duty ratio
D _OUT is calculated and the control valve 6 is opened at this valve opening duty ratio D _OUT (Fig. 6b). After the TDC6 signal, the ECU 9 similarly adds an increase in auxiliary air corresponding to the electrical load of the first electrical device 16 every time the TDC signal is input until the ON signal of the first electrical device 16 is input, that is, until immediately after the TDC10 signal. Valve opening duty ratio
D _OUT is calculated and the control valve 6 is opened at this valve opening duty ratio D _OUT . Immediately after the TDC5 signal, the control valve 6 increases the amount of auxiliary air corresponding to the electrical load of the first electrical device 16 and supplies it to the engine 1, as described above, but the control valve 6 increases the amount of auxiliary air corresponding to the electrical load of the first electrical device 16 and supplies it to the engine 1. It is after the occurrence of the TDC8 signal that the corresponding amount of fuel is supplied to the engine 1. this is
The period from the generation of the TDC5 signal to the generation of the TDC8 signal is a period in which the amount of intake air gradually increases, and this increase in the amount of intake air cannot be accurately detected mainly due to the detection delay of the absolute pressure sensor 13. (Figure 6a). Therefore, if no measures are taken to prevent this phenomenon, the fuel supply will continue to increase even though the amount of intake air supplied to the engine 1 is substantially increased immediately after the TDC5 signal or immediately after the TDC7 signal. As a result, the amount of fuel supplied becomes insufficient and the air-fuel mixture supplied to the engine 1 becomes diluted. Depending on the situation, engine stalling or hunting may occur.

Next, the OFF signal of the first electric device 16 that is in the OFF state between the TDC10 signal and the TDC11 signal is
Detected after TDC11 signal. First electrical device 16
Since the load on the engine is reduced when TDC11 turns off, the amount of auxiliary air corresponding to the electrical load of the first electric device 16 is no longer required, so the amount of auxiliary air supplied to the engine 1 after the TDC11 signal value is equal to the amount of the first electric device 16. The amount of auxiliary air is reduced from the amount of auxiliary air corresponding to the electrical load of the device 16, and this amount of auxiliary air is
is supplied to the engine 1 via. In such a case, as well as when increasing the amount of auxiliary air,
The period from the generation of the TDC11 signal to just before the generation of the TDC14 signal is a period in which the intake air amount gradually decreases, and due to the detection delay of the absolute pressure sensor 13 in response to this decrease in the intake air amount, the fuel supply to the engine 1 is reduced by the intake air amount. Unable to keep up with the decrease in fuel consumption, the amount of fuel supplied becomes excessive, and the mixture supplied to the engine 1 becomes over-enriched, resulting in deterioration of exhaust gas characteristics during idling, hunting, etc. (FIGS. 6a and 6b).

In order to eliminate the above-mentioned problem, the amount of auxiliary air via the control valve 6 is increased immediately after the TDC5 signal, and then
Engine 1 immediately after TDC5 signal to TDC7 signal
Immediately after the TDC11 signal, the amount of auxiliary air flowing through the control valve 6 increases as described above. After the weight is reduced,
Immediately after the TDC11 signal or immediately after the TDC13 signal, the amount of fuel supplied to the engine 1 is reduced by a predetermined amount and supplied (this period during which the fuel is reduced by a predetermined amount and is supplied is hereinafter referred to as a "fuel reduction period").

To explain this fuel supply control method more specifically, at the same time as the ON signal of the first electric device 16 is detected, the stored value of the counter NP1 (not shown) in the ECU 9 shown in FIG. corresponds to,
A specific predetermined value for the first electrical device 16, e.g.
In addition to setting NP1=3, the opening time T _OUT of the fuel injection valve 10 is set based on the following equation (1) in order to correct the intake air amount detection error caused by the detection delay of the absolute pressure sensor 13 described above.

T _OUT =K・Ti+T _AIC ...(1) Here, Ti is the basic valve opening time calculated by the ECU 9 based on the engine operating parameter signals from the absolute pressure sensor 13 and the engine rotation angle position sensor 15, and K is the basic valve opening time. This is a correction coefficient for correcting the basic valve opening time Ti according to each operating state, and is a value calculated by the ECU 9 based on the detection signals of the throttle valve opening sensor 11 and the cooling water temperature sensor 14. The T _AIC term is a predetermined constant time added to correct the intake air amount detection error, and is set to T _AIC = T _AICP during the above-mentioned fuel increase period.

The memory value of counter NP1 is 1 for each TDC signal input.
The valve opening timing T _OUT of the fuel injection valve 10 is calculated for each TDC signal from TDC5 signal to TDC7 signal while the stored value of counter NP1 is not zero.
is added with a predetermined value T _AICP , and the amount of fuel corresponding to this calculated value T _OUT is supplied to the engine 1 (Fig. 6c).
and e). The stored value of the counter NP1 immediately after the TDC8 signal is zero (Fig. 6c), and from this point on, the predetermined value T _AICP is no longer added to the valve opening time T _OUT (T _AIC in equation (1) is Since the detection delay period for changes in the intake air amount (set to zero), that is, the fuel increase period, has already passed and the intake air amount can be detected accurately (see Figure 6 a, c, and e, when the supply of auxiliary air Accurate amount of fuel can be supplied according to the amount.

Next, when an off signal of the first electrical device 16 is detected immediately after the TDC11 signal, the valve opening duty ratio D _OUT of the control valve 6 is decreased by a value corresponding to the electrical load of the first electrical device 16 (Fig. 6b). ). and TDC11
Immediately after the signal, counter NM1 in ECU9 (not shown)
The stored value corresponds to the fuel reduction period and is set to a predetermined value specific to the first electric device 16, for example, NM1=3, and the opening time of the fuel injection valve 10.
T _OUT is subtracted by a predetermined value T _AICM , i.e., Eq.
Calculated by setting the T _AIC term in (1) to T _AIC = −T _AICM ,
Fuel is supplied to the engine 1 based on this calculated value T _OUT . The stored value of the counter NM1 is decremented by 1 each time the TDC signal is input, and the value stored in the counter NM1 is
A period in which the stored value of is not zero corresponds to the fuel reduction period. During this period, that is, from immediately after the TDC11 signal to immediately after the TDC13 signal, the amount of fuel supplied to the engine 1 is the amount of fuel corresponding to the valve opening time T _OUT obtained by subtracting the valve opening time of the fuel injection valve 10 by the predetermined value T _AICM , as described above. (Fig. 6 a, c, e).

Immediately after the TDC14 signal, the memorized value of the counter NM1 becomes zero, and from this point on, the valve opening time is no longer reached.
Although the predetermined value T _AICM is not subtracted from T _OUT (formula (1)
(T _AIC is set to zero), the detection delay time for changes in intake air amount, that is, the fuel reduction period, has already passed and the intake air amount can be detected accurately (see Figure 6 a, c, and e). ) Accurate amount of fuel can be supplied in accordance with the amount of auxiliary air supplied.

However, as described above, even if the first electrical device 16 is turned off, if the battery 19 is exhausted and the engine is under a load that causes the generator 20 to be in a full power generation state, the amount of auxiliary air is Depending on the off-state of the first electrical device 16, the average value V _BX of the output voltage value V _B of the battery 19 does not decrease immediately after the TDC9 signal, but recovers to the predetermined value V _BEG between the TDC15 signal and the TDC16 signal, for example. At this time, the auxiliary air amount, that is, the valve opening duty ratio D _OUT decreases immediately after the TDC16 signal (dotted line in FIG. 6b). Therefore, the first electrical device 1
If the start of the decrease in the opening time T _OUT of the fuel injection valve 10 described above is not delayed during the period corresponding to the period from the switch-off of No. 6 to the decrease of the auxiliary air amount, that is,
In such a case, if the amount of fuel corresponding to the T _AICM value is immediately reduced upon detection of the off signal of the first electric device based on the above-described fuel supply control method,
Between the TDC11 signal and the TDC15 signal, the air-fuel mixture supplied to the engine becomes diluted, and even if the amount of auxiliary air is maintained, the engine speed decreases.

Therefore, while the auxiliary air amount, that is, the valve opening duty ratio D _OUT of the control valve 6 is not decreasing, the counter
Even if the memory value of NM1 is set, the valve opening time T _OUT of the fuel injection valve 10 is not subtracted, and the counter
Without subtracting the set value of NM1, after the TDC16 signal, the valve opening time T _OUT and counter NM1 are calculated in the same way as above.
When you start subtracting the set value of (Fig. 6 a, b, e)
Dotted line and Figure 6 d) Accurate amount of fuel can be supplied in accordance with the amount of auxiliary air.

FIG. 7 is a flowchart illustrating the control procedure of the fuel supply amount increase/decrease control method described in FIG. 6, which is executed within the ECU 9. In addition, in FIG. 6, the case where only the first electric device 16 applies a load to the engine has been explained, but in this flowchart, the first, second and third electric devices 16, 17, 18 (hereinafter in order “first load”) are applied. ''...referred to as the "third load") applies a load to the engine.

When this program is called for each TDC signal (step 31 in FIG. 7), steps 33 to 37 of this program are repeatedly executed the same number of times as the number of electrical loads on the engine. That is, in this embodiment, first, second, and third loads are assumed, so steps 33 to 37 are repeated three times. For this repeated execution, a control variable i is set to i=1 in step 32. Next, it is determined whether or not the i-th load, that is, the first load (first electrical device 16), is in the on state (step 33). If it is in the on state, it is then determined whether it was in the on state at the time of the previous TDC signal. (Step 34). step 34
If the determination result is negative (No), that is, the ON signal of the first load is detected for the first time in this TDC signal, and the value stored in the counter NP1 is set to correspond to the fuel increase period specific to the first load. Set a predetermined value η _P1 , for example, NP1=3 (step 35), and set the memorized value of counter NM1 to zero (step 36).
Then proceed to step 37. If it is determined in step 34 that the first load was in the on state at the time of the previous TDC signal (if the determination result is affirmative (YES))
Proceed to step 36 above.

When it is determined in step 33 that the first load is not in the on state, the process proceeds to step 38, where it is determined whether or not the first load was in the on state at the time of the previous TDC signal. If the determination result in step 38 is affirmative (YES), that is, when it is detected that the first load is reversed from on to off with the current TDC signal, the value stored in counter NM1 is changed to the fuel reduction specific to the first load. A predetermined value η _n1 corresponding to the period is set, for example, NM1=3 (step 39), and then the stored value of the counter NP1 is set to zero (step 40), and the process proceeds to the aforementioned step 37. If the determination result in step 38 is negative (NO), the process proceeds to step 40 described above.

As mentioned above, the first load counter NP1 or
When the setting of the memory value of NM1 is completed, next, in step 37, it is determined whether the control variable i is i=3 or not, that is, whether the memory value of each counter of the first load to the third load has been set. If the answer is negative (NO), add 1 to the number i (step 41), return to step 33, and apply the next load in the same manner as explained using the first load as an example. Set the stored value of each counter.

If the determination result in step 37 is affirmative (YES),
That is, when the setting of each stored value of the counters related to all loads is completed, the process proceeds to step 42. In step 42, it is determined whether the sum ΣNPi of each stored value of the counter NPi is greater than zero or not. If the result of this determination is negative (NO), that is, when the sum ΣNPi = 0, then the sum of each stored value of the counter NMi is determined. It is determined whether the sum ΣNMi is greater than zero (step 43).
In step 42, it is determined whether the sum ΣNPi of each stored value is greater than zero or not, because the period in which the stored value of the counter NP1 is not zero is the fuel increase period related to the first load, and the stored value of each of the counters NP2 and NP3 is This is because the period in which the value is not zero is the fuel increase period for the second and third loads, respectively, and the period in which any of the stored values of each counter NP1 to NP3 is not zero is the overall fuel increase period. . Similarly, the overall fuel reduction period is determined by each counter.
Since this is a period in which any one of the stored values NM1, NM2, and NM3 is not zero, it is determined in step 43 whether the sum ΣNMi of each stored value is greater than zero.

If the determination result is affirmative (YES) in step 42, that is, it is determined that it is the fuel increase period, each of the stored values of all counters NPi and all counters NMi is subtracted by 1 (step 44,
45), calculation formula (1) for the valve opening time T _OUT of the fuel injection valve 10
Set the T _AIC term of T AICP to the predetermined value T _AICP (step
46) and terminate the program (step 47).

If the determination result in step 43 is positive (YES),
Proceeding to step 48, it is determined whether the η _IMFLG value set in step 11 or step 14 of the electric load term D _Eo calculation subroutine in FIG. 4 is zero. If this determination result is negative (NO), that is, if the battery 19 is exhausted and the load that causes the generator 20 to be in a full power generation state is applied to the engine, then the T _AIC of equation (1)
Set the term to zero (step 49), and set the fuel injector 10 to
The T _AICM value is not subtracted in the calculation of the valve opening time T _OUT , and the stored values of the counters NM1 to NM3 are not counted down (see Figure 6 d).
TDC11~15 signal).

If the determination result in step 48 is positive (YES),
That is, the average value V _BX of the output voltage value V _B of the battery 19
generator 2 recovers to the predetermined value V _BEG and starts the engine.
If it is determined that the 0 load has been released and the fuel reduction period has begun, each memory value of all counters NMi is subtracted by 1 (step 50), and the calculation formula (1) for the valve opening time T _OUT is Set the T _AIC term to the specified value (−T _AICM )
(Step 51) and terminate the program (Step 47).

If the determination result in step 43 is negative (NO), that is, the sum ΣNMi = 0 and the fuel reduction period ends, the process proceeds to step 49, where the T _AIC term is set to zero and the fuel reduction is no longer performed. Execution of the program is ended (step 47).

8 to 13 show the second control method of the present invention.
An example is shown below. In the second embodiment shown in FIG. 8, an adder circuit 22 is interposed between the ECU 9 and the first, second, and third electrical devices 16, 17, and 18 having the configuration shown in FIG. That is, the first electric device 16 connected to the connection point 19a via the switch 16a
is connected to the input terminal 22a of the adder circuit 22, and the connection points between the ground side terminals of the second and third electric devices 17 and 18 and the respective switches 17a and 18a are connected to the respective input terminals 22b of the adder circuit 22. ,22
connected to c. Then, the output terminal of the adder circuit 22 is connected to the ECU 9, and the individual switches 16a, 17a, 18a are turned on and off as shown in FIG.
Level correction circuit 908 of ECU 9 for each off signal
The output of the adder circuit 22 is input to the level correction circuit 908 instead of being input to the level correction circuit 908 . Furthermore, in order to supply operating power to the adder circuit 22, the connection point 19a
and the adder circuit 22 are connected.

FIG. 9 is a circuit diagram showing the internal configuration of the adder circuit 22 shown in FIG.
The voltage supplied to the adder circuit 22 via the constant voltage power supply 221 is converted into a constant voltage Vcc, and this constant voltage Vcc is supplied to each circuit element described later.

Input terminal 22a to which the first electrical device 16 is connected
is through forward diode D1 and resistor R1.
It is connected to the base of the npn transistor Tr1, the emitter of the transistor Tr1 is grounded, and a resistor R2 is connected between the base and emitter of the transistor Tr1. The collector of the transistor Tr1 is connected to the base of the pnp transistor Tr2 via the resistor R3, and the base of the transistor Tr2 is connected to the base of the pnp transistor Tr2 via the resistor R3.
The emitters are connected through a resistor R4, and the constant voltage Vcc is supplied to the emitters. Transistor Tr
2 is grounded via a resistor R5 and connected to a common connection point 222 via a resistor R6.

Input terminal 22b to which the second electrical device 17 is connected
through diode D2 and resistor R7 in the opposite direction.
A resistor R8 is connected to the base of the pnp transistor Tr3, and a resistor R8 is connected between the base and emitter of the transistor Tr3.
The set voltage Vcc is supplied to the emitter. The collector of transistor Tr3 is grounded via resistor R9 and connected to common connection point 222 via resistor R10.

Input terminal 22c to which the third electrical device 18 is connected
is connected to the base of the pnp transistor Tr4 via a reverse diode D3 and a resistor R11, and a resistor R is connected between the base and emitter of the transistor Tr4.
12, and the constant voltage Vcc is supplied to the emitter. The collector of the transistor Tr4 is grounded through series-connected resistors R13 and R14, and the connection point between the resistors R13 and R14 is connected to the common connection point 222 through a resistor R15.

Furthermore, a resistor R1 to which the constant voltage Vcc is supplied
6 is grounded via a resistor R17 and connected to the common connection point 222 via a resistor R18.

The common connection point 222 is connected to the non-inverting input terminal of the operational amplifier 223, and the inverting input terminal of the operational amplifier 223 is grounded through a resistor R19 and connected to the output terminal of the operational amplifier 223 through a feedback resistor R20. The output terminal of this operational amplifier is the level correction circuit 9 of the ECU 9 mentioned above.
08 (Fig. 3).

Next, the operation of the adder circuit 22 according to the second embodiment will be explained.

When the switch 16a of the first electrical device 16 is closed (turned on), part of the current supplied from the battery 19 flows through the diode D1 and the resistors R1 and R2, creating a potential difference between the base and emitter of the transistor Tr1, causing the transistor Tr1 becomes conductive.
When transistor Tr1 becomes conductive, resistors R4 and R3
and a constant voltage power supply 22 through the transistor Tr1.
Current flows from 1 to ground, and transistor Tr2
When the base current is drawn and the transistor Tr2 becomes conductive, the resistor R is connected from the constant voltage power supply 221 to the ground.
A current flows through the resistor R5 and a predetermined voltage V ₁ corresponding to the first electrical device 16 is generated on both sides of the resistor R5.

When the switch 17a of the second electric device 17 is closed (turned on), the constant voltage power supply 221 connects the resistors R8 and R
7. A current flows to ground through the diode D2 and the switch 17a, and the base current of the transistor Tr3 is drawn in, making the transistor Tr3 conductive. When the transistor Tr3 becomes conductive, a current flows from the constant voltage power supply 221 to the ground through the resistor R9, and a predetermined voltage V ₂ corresponding to the second electric device 17 is generated across the resistor R9.

When the switch 18a of the third electric device 18 is closed (turned on), the constant voltage power supply 221 connects the resistor R12,
A current flows to ground through R11, diode D3, and switch 18a, and the base current of transistor Tr4 is drawn, making transistor Tr4 conductive. When the transistor Tr4 becomes conductive, a current flows from the constant voltage power supply 221 to the ground through the resistor R13 and the resistor R14 connected in series with the resistor R13. A predetermined voltage V ₃ corresponding to the third electrical device 18 is therefore developed across the resistor R14.

Moreover, regardless of the on-off state of the electrical devices 16, 17, 18, that is, the on-off state of each switch 16a, 17a, 18a, the resistor R connected in series
A current flows from the constant voltage power supply 221 to the ground through R16 and R17, and a predetermined voltage _V0 is generated across the resistor R17.

The above-described predetermined voltages V ₀ , V ₁ , V ₂ , and V ₃ are transmitted to the common connection point 222 via resistors R18, R6, R10, and R15, respectively. As a result, the output voltage E ₁ of the operational amplifier 223 is given by the following formula.

E ₁ = (V ₀ +SW16a・V ₁ +SW17a・V ₂ +SW18a・V ₃ )・G Here, G is the gain of the operational amplifier 223,
SW16a, SW17a, SW18a are each switch 16
It takes a value of 1 when a, 17a, and 18a are on, and takes a value of 0 when they are off. Therefore, the voltages V ₁ , V ₂ ,
V ₃ is the first, second and third electrical device 16, 17,
If the values of resistors R5, R9, R13 and R14 are selected to correspond to the power consumption of each of the 18 devices, the output voltage value _E1 of the operational amplifier 223 will be the sum of the power consumed by the electrical equipment at that time. will give.

Figure 10 is a flowchart of a calculation program for the electric load term D _Eo that is executed in the ECU 9 for each TDC signal. Steps that are the same as those in the flowchart shown in Figure 4 are given the same reference numerals and explanations will be omitted. .

In the flowchart of FIG. 10, the individual electrical devices 16-1 are
Instead of calculating the electrical load term D _Eo based on the on-off state of 8, first, in step 62, the output voltage value E ₁ of the operational amplifier 223 explained in FIG.
Next, the electrical load term D _Eo corresponding to this voltage value E ₁ is
For example, as shown in FIG. 11, the map value is determined from the map value set and stored in the ECU 9 such that it increases stepwise as the voltage value _E1 increases (step 63).

After the electric load term D _Eo is determined in step 63, steps 9, 12, and 13 are executed in the same way as in FIG. However, in the flowchart of FIG. 9, steps 11 and 14 shown in FIG. 4 are not provided because they are unnecessary. This is because, in the fuel increase/decrease control method of the second embodiment, the counter set for increasing or decreasing the amount of fuel is not set based on the on/off state of the electrical device, but is based on the electrical load factor as described later. This is because it is set based on the difference ΔD _Eo , so there is no need to use a flag.

FIG. 12 is a flowchart explaining the control procedure of the fuel increase/decrease control method.
Executed for each signal.

When this program is called (step 71),
First, it is determined whether the difference ΔD _Eo between the electrical load term at this time and the previous time is greater than 0 (step 72).
If the determination result is affirmative (YES), a predetermined value ηp is called according to the magnitude of ΔD _Eo (step 73), this predetermined value ηp is added to the value stored in the counter NP (step 74), and the step described later is executed. Proceed to 78. For example, as shown in FIG. 13, this predetermined value ηp is set to take a larger positive integer value as the magnitude of the difference ΔD _Eo becomes larger, and these predetermined values ηp
It is stored in the ECU 9 in advance.

If the determination result in step 72 is negative (NO),
Next, in step 75, it is determined whether the difference ΔD _Eo is smaller than zero. If this determination result is affirmative (YES), that is, if the electrical load term this time has decreased compared to the previous time, a predetermined value ηm is called according to the magnitude of (-ΔD _Eo ) (step 76), and the Predetermined value ηm
is added to the memorized value of counter NM (step
77), proceed to step 78, which will be described later. This predetermined value ηm
For example, as shown in Figure 15, (-
The larger the magnitude of ΔD _Eo ), the larger the positive integer value, and these predetermined values ηm are
It is stored in the ECU 9 in advance.

The value of ΔD _Eo used for the determination in steps 72 and 75 is the difference between the electrical load term at this time and the previous time, ΔD _Eo = D _Eo −, similar to ΔD _Eo used at step 9 in FIG.
Calculated as D _Eo-1 . However, as shown by the broken line in FIG. 6b, for example, even if the first electric device 16 is turned off, it is determined that the generator 20 continues to operate and the valve opening duty ratio D _OUT is maintained. , the current electrical load term D _Eo used to calculate the difference ΔD _Eo used in steps 72 and 75 of FIG. 12 is replaced with the previous electrical load term D _Eo-1 in step 12 of FIG. Therefore, the difference ΔD _Eo takes a negative value only when the process proceeds from step 9 or 12 in FIG. 10 to step 15 without passing through step 13. That is, in the second embodiment, TDC16 in FIG.
Immediately after the signal is generated, the determination result at step 75 in FIG. 12 becomes affirmative (YES) and the counter NM is set.

If the determination results in steps 72 and 75 are both negative (NO), that is, if the difference ΔD _Eo between the electrical load terms this time and the previous time is zero, the process advances to step 78.

Next, in step 78, the stored value of counter NP is set to 0.
If the determination result is affirmative (YES), it is determined that it is the aforementioned fuel increase period, and the stored value of the counter NP is subtracted by 1, and the counter NM is reset to 0 (step 79). ，
80), calculation formula (1) for the valve opening time T _OUT of the fuel injection valve 10
Set the T _AIC term of T AICP to the predetermined value T _AICP (step
81), and ends the execution of the program (step 82).

If the determination result in step 78 is negative (NO), it is then determined whether the stored value of the counter NM is greater than 0 (step 83), and if this determination result is negative (NO), the fuel amount is increased or decreased. Since there is no need to do so, the T _AIC term is set to 0 (step 84), and the execution of the program is terminated (step 82).

If the determination result in step 83 is affirmative (YES), it is determined that it is the aforementioned fuel reduction period, and the counter is activated.
The stored value of NM is subtracted by 1, and the T _AIC term is set to a predetermined value (-T _AICM ) (steps 85, 86), and the execution of the program is ended (step 82).

In this way, in the second embodiment, each electrical device 16,
Instead of inputting the individual on-off signals of the electrical devices 17 and 18 to the ECU 9, as shown in FIGS. Since the voltage value corresponding to the sum is determined by the adding circuit 22 and this value is inputted to the ECU 9, there is no need to provide two counters for each electrical device as in the first embodiment, which is used for fuel increase/decrease control. Only two counters are required. In addition, these counters can be set for each electrical device.
Since the setting is not based on the on-off states of 6, 17, and 18 but based on the value of the difference ΔD _Eo between the electrical load terms, there is no need to use a flag as in the first embodiment.

It should be noted that in step 9 of FIGS. 4 and 10, it was determined whether the difference ΔD _Eo between the electric load terms is smaller than zero, but this determination may be made not on the basis of zero but on a predetermined amount. For example, the difference in electrical load terms ΔD _Eo
When ΔD Eo takes a negative value, the difference ΔD _Eo represents the amount of decrease in electrical load, so the decrease amount ΔD _Eo is compared with a certain predetermined amount ΔD _G , and when this decrease amount ΔD _Eo is larger than the predetermined amount ΔD _G , the corresponding difference ΔD Eo is determined. Even if it is determined that there is a high probability that the power necessary for operating the electrical device related to the reduction of the electrical load is being supplied not only from the generator 20 but also from the battery 19, the process proceeds to step 12 in FIG. 4 or FIG. 10. good.

As explained above, the first invention includes at least one electrical device, a battery for supplying power to the electrical device, and a generator driven by the crankshaft of an internal combustion engine, and controls the amount of intake air. In the idle speed control method of controlling the idle speed of an internal combustion engine by a control valve to be adjusted, the on-off state of the at least one electrical device is detected,
The intake air amount is controlled to be increased or decreased by a predetermined amount by the control valve according to the detected on-off state of the at least one electrical device, and the state of the generator immediately after the electrical device is switched from on to off. , and when it is determined that the generator is placing a high load on the internal combustion engine, the predetermined amount of reduction control is not performed. This can reduce driver discomfort and the risk of engine stalling.

Furthermore, according to a second invention, there is provided a control valve for adjusting the amount of intake air, the control valve including at least one electrical device, a battery for supplying electric power to the electrical device, and a generator driven by a crankshaft of an internal combustion engine; In an idle speed control method for controlling the idle speed of an internal combustion engine using a fuel control valve, the on-off state of the at least one electrical device is detected, and the on-off state of the detected at least one electrical device is changed to Accordingly, the amount of intake air is increased or decreased by a predetermined amount by the control valves, and the amount of fuel supplied to the internal combustion engine is controlled to be increased or decreased by a predetermined amount;
Detecting the state of the generator immediately after the electric device is switched from on to off, and controlling the amount of intake air and the amount of fuel when it is determined that the generator is placing a high load on the internal combustion engine. Since this is not performed, the air-fuel ratio of the air-fuel mixture supplied to the engine can be maintained at an appropriate value regardless of whether the electrical device is on or off.

[Brief explanation of drawings]

Figure 1 is a timing chart for the idle speed control of the present invention, in which figure a shows the on-off state of the electrical device, figure b shows the change in the output voltage of the battery, and figure c shows the auxiliary air flow control valve. Figure d shows the change in the valve opening duty ratio D _OUT at engine speed Ne.
2 is an overall configuration diagram of a first embodiment of a control device to which the idle speed control method according to the present invention is applied, and FIG. 3 is a diagram showing the electronic control unit (ECU) shown in FIG. 2. ), Figure 4 is a flowchart of the calculation program for the electrical load term used to calculate the opening duty ratio of the auxiliary air flow control valve, and Figure 5 is the calculation for calculating the average value of battery voltage. The flowchart of the program, FIG. 6, is a timing chart showing a fuel amount control method that is compatible with the auxiliary air amount supply control of the first embodiment, and FIG. Figure b shows the changes in the intake air amount, Figure c shows the on-off signal of the first electric device, changes in the opening duty ratio of the auxiliary air flow control valve, changes in the battery output voltage, and the generation timing of the TDC signal. d shows the changes in the stored values of counters NP1 and NM1 in the ECU, d shows the changes in the stored values of counter NM1 when the valve opening duty ratio in b is maintained as shown by the dotted line, and e shows the changes in the stored values of counter NM1. A chart showing the valve opening time correction value T _AIC of the fuel injection valve during an increase or decrease period, FIG. 7 is a flowchart showing the control procedure of the fuel supply amount control method shown in FIG. 6, and FIG. 8 is a flowchart showing the control procedure of the fuel supply amount control method shown in FIG. 6. 9 is an electric circuit diagram of the addition circuit shown in FIG. 8, and FIG. 10 is an electric load of the second embodiment. FIG. 11 is a graph showing the relationship between the output voltage of the adder circuit shown in FIG. 9 and the electric load term, and FIG. 12 is a flowchart of the calculation program of the fuel amount control method of the second embodiment. The flowchart shown in FIG. 13 is a graph showing the relationship between the difference in electrical load terms and the predetermined values ηp and ηm set for the counters NP and NM. DESCRIPTION OF SYMBOLS 1... Internal combustion engine, 3... Intake passage, 5... Throttle valve, 6... Auxiliary air amount control valve, 8... Air passage, 9...
electronic control unit (ECU), 10... fuel injection valve, 13... intake passage absolute pressure sensor, 16,
17, 18...Electrical device, 19...Battery, 20...
Generator, 21...Battery output voltage detector, 22...
Addition circuit, V _B ...battery output voltage value, V _BX ...average value, V _BEG ...predetermined value, D _OUT ...control valve opening duty ratio, D _Eo ...electrical load term (corrected operating amount), T _AIC ...
Correction injection amount.

Claims (1)

[Scope of Claims] 1. The internal combustion engine includes at least one electrical device, a battery that supplies power to the electrical device, and a generator driven by the crankshaft of an internal combustion engine. In the idle speed control method for controlling the idle speed of an engine, an on-off state of the at least one electrical device is detected, and the control valve is controlled according to the detected on-off state of the at least one electrical device. controlling the amount of intake air to be increased or decreased by a predetermined amount, detecting the state of the generator immediately after the electric device is switched from on to off, and determining that the generator is under high load with respect to the internal combustion engine; A method for controlling an idle rotation speed of an internal combustion engine, characterized in that the control for reducing the predetermined amount is not performed when the control is performed. 2. Claim 1, characterized in that, after detecting that the state of the generator is under high load with respect to the internal combustion engine, the power is reduced by the predetermined amount when it is determined that the high load is no longer high. The method for controlling the idle speed of an internal combustion engine according to item 1. 3. The state of the generator is detected based on a battery voltage value, and when the battery voltage value is less than a predetermined value, it is determined that the generator is under high load with respect to the internal combustion engine. term or second
A method for controlling the idle speed of an internal combustion engine as described in . 4. The idle speed control method for an internal combustion engine according to claim 3, wherein the battery voltage value is an average value of the detected battery voltages. 5 At least one electrical device, a battery that supplies power to the electrical device, and a generator driven by the crankshaft of the internal combustion engine. In the idle speed control method for controlling the idle speed of an engine, an on-off state of the at least one electrical device is detected, and both control valves are adjusted according to the detected on-off state of the at least one electrical device. controls the amount of intake air to be increased or decreased by a predetermined amount, and controls the amount of fuel supplied to the internal combustion engine to be increased or decreased by a predetermined amount, detects the state of the generator immediately after the electric device is switched from on to off, and A method for controlling an idle speed of an internal combustion engine, characterized in that when it is determined that a generator is placing a high load on the internal combustion engine, the intake air amount reduction control and the fuel amount reduction control are not performed. 6. A patent characterized in that, after detecting that the generator is under high load with respect to the internal combustion engine, the intake air amount and fuel amount are reduced when it is determined that the generator is no longer under high load. A method for controlling the idle speed of an internal combustion engine according to claim 5. 7. Claim 5, characterized in that the state of the generator is detected based on a battery voltage value, and when the battery voltage value is less than a predetermined value, it is determined that the generator is under high load with respect to the internal combustion engine. Section or 6th
A method for controlling the idle speed of an internal combustion engine as described in . 8. The idle speed control method for an internal combustion engine according to claim 7, wherein the battery voltage value is an average value of the detected battery voltages.