JPH0551769B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to an electronic control device that controls the fuel supply amount, injection timing, intake air amount, ignition timing, etc. of an engine, such as an internal combustion engine, mainly for an automobile.
In particular, it relates to technology for predicting and avoiding engine stalls.

[Prior art]

2. Description of the Related Art Conventional comprehensive engine electronic control devices include those shown in FIGS. 1 and 2, for example.

The above equipment is compatible with SAE paper 800056 and
800825, FIG. 1 is a hardware configuration diagram, and FIG. 2 is a correspondence diagram of control system sensors, signals, and actuators.

In Fig. 1, 1 is an air flow sensor that detects the intake air amount, 2 is a throttle position switch that detects when the throttle valve is fully closed, and 3 is an air flow sensor that adjusts the intake air amount to control the idle rotation speed.
AAC valve, 4 is an EGR control valve that controls the amount of exhaust gas recirculation, 5 is a negative pressure converter (a combination of a constant pressure valve and an on/off solenoid valve) that controls the opening of the AAC valve 3 and the EGR control valve 4, 6 is a fuel injection valve, 7 is an oxygen sensor, 8 is an ignition coil, 9 is a distributor, 10 is a three-way catalyst, 11 is an exhaust temperature sensor, 12 is a neutral switch that detects the neutral position of the transmission, 13 is a crank A crankshaft sensor detects the rotation angle of the shaft, 14 is a cooling water temperature sensor, 15 is a fuel pump, 16 is a fuel pump relay, 17 is a vehicle speed sensor, and 18 is an air conditioner switch.

The above device is configured to input signals from various sensors as shown in FIG. 2 to a microcomputer (not shown) to comprehensively control various actuators as shown.

The control contents of the above device are as follows.

(1) Fuel supply amount control (EGI) according to intake air amount.

(2) Air supply control (ISC) that maintains a constant engine speed at idle.

(3) Ignition timing control (IGN) according to engine speed and engine load.

(4) Exhaust gas recirculation amount control (EGR) according to engine speed and engine load.

The above control contents are changed according to various operating conditions.

However, in the conventional devices described above, control is performed only based on the results of actual engine operation, so the control response is slow and it is difficult to effectively prevent engine stalls from occurring. It was difficult.

Furthermore, conventional engine stall prevention devices that have been proposed increase the amount of intake air or fuel to increase the torque generated by the engine when the engine is about to stall; Since the speed of the engine is not very fast, there is a problem that the above-mentioned control cannot be used in time to actually stall the engine, making it impossible to effectively avoid the engine stall.

[Purpose of the invention]

The present invention has been made in order to solve the problems of the prior art as described above, and is capable of predicting the occurrence of an engine stall based on the operating state of the engine, etc., and controlling the engine to reduce the engine load in that case. An object of the present invention is to provide an electronic engine control device that avoids engine stalling.

As described above, if the engine load is immediately reduced when an engine stall is predicted, surplus torque can be generated quickly, so that an engine stall can be effectively avoided.

[Summary of the invention]

FIG. 3 is a block diagram showing the overall configuration of the present invention.

In FIG. 3, 20 detects the operating state of the engine and auxiliary equipment (transmission, air conditioner, etc.) (for those used in vehicles, the vehicle state, such as the vehicle speed, is also included; hereinafter collectively referred to as the engine operating state). Various sensor groups (200, 210, 22 in Figure 4 below)
0,230,250,270,280, etc.).

A prediction means 21 determines the operating state of the engine from the outputs of the sensor group 20 and predicts the occurrence of engine stalling.

Reference numeral 22 denotes a control means, which immediately reduces the engine load when the prediction means 21 predicts the occurrence of an engine stall.

To rapidly reduce the engine load, for example, stop the load on auxiliary equipment that is mechanically driven by the engine, such as the air conditioner or alternator (mechanically cut off the load using an electromagnetic clutch, etc., or reduce the electric power load). There is a method that turns off electrical loads such as lights, heater fans, anti-fog hot wires, radios, stereos, etc. In the latter case, it is possible to completely shut off things that are not directly related to driving safety, such as heat wires and radios, but it is not possible to completely turn off things like headlights. Therefore, in such a device, it is preferable to control the duty of the supplied power and reduce the power consumption within a safe range.

[Embodiments of the invention]

Hereinafter, the present invention will be explained in detail based on Examples.

First, the outline of the system of the electronic control device of the present invention will be explained based on FIG.

FIG. 4 shows the case where the system is applied to a 4-cycle 6-cylinder engine, and the objects to be controlled are as follows.

(1) Fuel injection (EGI) control (EGI OUT110) that is performed by controlling the valve opening start timing and valve opening time of the injector 35 provided in each cylinder of the engine.

(2) Ignition (IGN) control (IGN OUT120) that controls energization/cutoff of the primary coil of the ignition coil 38 to control ignition timing and energization time.

(3) Adjust the lift amount of EGR valve 30 to VCM valve 4.
Exhaust gas recirculation (EGR) control (EGR OUT130) is performed by controlling negative pressure using 0.

(4) Change the lift amount of AAC valve 50 to VCM valve 4.
Idle rotation (ISC) control (ISC) is performed by controlling the amount of air bypassing the throttle valve 510 by controlling the negative pressure using 0.
OUT150).

The above are the main objects of control, but there are also the following as incidental control or information output. (5) On/off control of fuel pump 530 by control of fuel pump relay 60 (F/P
(OUT160), (6) Output of fuel consumption data to the fuel consumption meter 70 (FCM OUT170), (7) System self-diagnosis and data exchange with Checkka 2000 or vehicle information providing device 2500 (CHECK), (8)
Alarm lamp 80 for warning based on self-diagnosis results
Output to (ALARM OUT180), (9) Display of self-diagnosis results, etc. to display 1900 (MONIT). (Ten)
Control (AIR
CON).

In order to perform the above control and output, the following control information is obtained from the engine and each part of the vehicle.

(1) From the crank angle sensor 200 built into the distributor 520, the REF signal 201 rises every 120 degrees at the rotation angle of the crankshaft (twice the rotation angle of the distributor) and the REF signal 201 rises every 1 degree. A POS signal 202 in which falling edges occur alternately is obtained.

By counting this POS signal 202 for a predetermined period of time, an engine rotation speed signal 203 is obtained.

(2) The intake air amount Q _a of the engine is detected by the air flow meter 210. Note that the intake air amount Q _a is the air flow meter output voltage signal (AFM) 211
is in an inversely proportional relationship.

(3) The output voltage of the O ₂ sensor 220 changes depending on the oxygen concentration in the exhaust gas, and a signal (O ₂ ) 221 corresponding to the air-fuel ratio is obtained.

(4) A voltage signal (T _w ) 231 representing the engine temperature is obtained by the water temperature sensor 230.

(5) The on-vehicle battery 240 supplies electricity to various parts of the control system. The control unit 1000 is supplied with a main power supply 241 via a control unit relay 540 and an auxiliary power supply 242 directly input from a battery 240. The voltage signal (V _B ) 241 of the main power supply is also used as information for control. In addition, the ignition switch 260
Of course, the ON terminal 262 is in the ON position,
Since battery voltage is applied even at the START position, the main power 241 is supplied to the control unit 1000 even during cranking.

(6) A signal (VSP) 251 having a pulse density proportional to the vehicle speed is obtained by the vehicle speed sensor 250.

(7) The ignition switch 260 is a switch that the driver operates to start and operate the engine, and the voltage signal (START) 2 at its START terminal
61, it can be known whether or not cranking is in progress.

(8) The throttle valve sensor 270 outputs a throttle opening signal (TVO) 271 proportional to the opening of the throttle valve.

(9) The air conditioner switch 280 is a switch that closes when the air conditioner is activated, and detects whether the air conditioner is in operation based on its terminal voltage signal (A/C) 281.

(10) The neutral switch 290 is a switch that closes when the gear position of the transmission is in the neutral or parking position, and the gear position of the transmission is detected by its opening/closing signal (NEUT) 291.

Each of the signals described above is input to and output from control unit 1000. In addition to input/output to the control unit 1000, a checker 2000 for diagnosing the control system and displaying the results is connected via a check connector 2010. Also, vehicle information providing device 2500
and is connected via a data transfer connector 2510. The control unit 1000 has a microcomputer, determines the control state of each controlled object based on the above-mentioned control information (input signals), issues a control signal (output signal), and optimally controls the engine. Outputs information related to.

Next, the circuit configuration of the control unit 1000 that comprehensively performs the above-mentioned control will be described with reference to FIG.

In FIG. 5, 1100 is a signal shaping circuit which inputs various input signals from the engine and various parts of the vehicle, removes noise from these various input signals, absorbs surges, and controls the control unit 100.
In addition to preventing malfunctions due to zero noise and damage due to surges, it also amplifies and converts various input signals to the next input interface circuit 120.
Arrange it so that 0 can operate correctly. 120
0 is an input interface circuit, which converts various input signals shaped by the signal shaping circuit 1100 into analog-to-digital (AD), counts the number of pulses during a predetermined time, and performs the following central processing. It is converted into a digital code signal so that the device (CPU) 1300 can read it as input data, and stored in an internal register as input data. 1300 is the central processing unit (CPU)
The bus 1 operates in synchronization with a clock signal based on the oscillation signal 1311 of the crystal resonator 1310.
320, and the memory 1400
The programs stored in the mask ROM 1410 and PROM 1420 are executed, various input data are read from each register in the input interface circuit 1200, and various output data are calculated by performing arithmetic processing.
Output data is sent to the register in 0 at a predetermined timing. The memory 1400 is a data storage device, and includes a mask ROM 1410, a PROM 1420,
RAM 1430 and storage memory 1440
has. And mask ROM1410 is CPU1
The program executed by 300 and the data used during program execution are permanently stored during IC manufacturing, and PROM 1420 is a mask ROM 14 that is likely to change depending on the car model and engine type.
10 are permanently written and stored in the control unit 1000 before being incorporated into the control unit 1000. In addition, the RAM 1430 is a readable and writable memory, and outputs intermediate data and result data of arithmetic processing to the interface circuit 1500.
The contents are stored temporarily before being sent out, and the stored contents are not retained when the ignition switch 260 is turned off and the main power supply 241 is turned off. Also, memory retention memory 14
40 stores and holds the result data and intermediate data of the arithmetic processing even when the ignition switch 260 is turned off, that is, when the vehicle is not being driven.

1350 is an arithmetic timer circuit, and the CPU 13
This is a multiplication circuit that enhances the functions of 00, and is a multiplication circuit that increases the speed of arithmetic processing.
It has an interval timer that sends an interrupt signal to the CPU 1300, a free-run counter that allows the CPU 1300 to know the elapsed time from a predetermined event to the next event, and the time when an event occurs. 1
500 is an output interface circuit;
Receives output data from the CPU 1300 into an internal register, converts it into a pulse signal with a predetermined timing and time width, or a predetermined period and duty ratio, or converts it into a switching signal of "1" or "0" and drives it. to circuit 1600. The drive circuit 1600 is a power amplification circuit that receives a signal from the output interface circuit 1500 and amplifies the voltage and current using a transistor or the like to drive various actuators or perform display.
Alternatively, it is connected to the control unit 1000 via a connector 2010 to send an output signal to a checker 2000 for diagnosing the control system and displaying the results.

1700 is a backup circuit that monitors the signal of the drive circuit 1600 to detect a failure;
When the CPU 1300, memory 1400, etc. fail and do not operate normally, the signal shaping circuit 11
In response to part of the signal from 00, the engine rotates and generates the minimum necessary control output to drive the vehicle, and also generates a switching signal 1701 to notify of the occurrence of a failure. 1750 is a switching circuit;
Switching signal 170 from backup circuit 1700
1 blocks the signal from the output interface circuit 1500 and allows the signal from the backup circuit 1700 to pass.

1800 is a power supply circuit, and each part has stabilized power supply voltages 1810, 1820, 1860, 188
0,1890 and CPU1300
RESET signal 1840, HALT which controls the operation of
A signal 1850, a battery voltage signal 1830, etc. are output.

Next, FIG. 6 is a block diagram showing an embodiment of a control system to which the present invention is applied and the flow of signals.

In an actual system, each block shown in FIG. 6 is realized by the hardware shown in FIG. 5 and a program executed by the CPU 1300, but it is shown in the form of a block diagram to make the image of the system easier to understand.

The overall configuration and general operation will be described below.

First, the actual operation pattern measuring means 3100 inputs various input signals 203, 211, 271, etc., samples them for a predetermined period at predetermined intervals, sequentially stores them (that is, stores them as time series data), and calculates the engine rotational speed. , intake air amount, throttle opening, etc., are stored in the form of pattern data as actual operation pattern data 3101.

On the other hand, various input signals 281, 291, etc. are also input to the operation change pattern creation means 3200, and according to the movement of the signals, operation patterns and patterns predicted as changes in engine speed, intake air amount, etc.
Select the data and select the operation change pattern data 3.
Output as 201.

The predicted motion pattern synthesis means 3300 inputs actual motion pattern data 3101 and motion change force pattern data 3201, synthesizes and processes both, and calculates future motion patterns such as rotation, intake air amount, throttle, etc. Predicted motion pattern data 3301 that predicts what will happen is created. If the motion change pattern is zero, the predicted motion pattern data 3301 is the actual motion pattern data 3.
It will be the same as 101.

The actual state determining means 3400 receives various input signals 20
3,211, 231, 271, 281, 291, etc., the engine state, for example, an unsteady state such as engine stall, acceleration, deceleration, gear change, etc., is determined, and the actual state data 3401 is determined.
Output.

The state-specific operation pattern storage means 3500 distinguishes each engine state according to the actual state data 3401, and stores actual operation pattern data 3101 such as rotation, intake air amount, throttle opening, etc. when the engine state occurs. Operation pattern by condition
It is stored as data 3501.

The state-specific operation pattern data 3501 is as follows:
As mentioned above, in addition to the actual operation pattern data 3101 generated and stored during use of the engine, it also includes data stored in advance at the time of manufacturing the control device.

The engine state estimation means 3600 compares and matches the predicted operation pattern data 3301 and the state-specific operation pattern data 3501, and when they match or approximately match, the engine state is determined to match the state-specific operation pattern data. The corresponding engine state is estimated and engine state estimation data 3601 is output.

The control output calculation means 3700 calculates control outputs 11 such as EGI, IGN, EGR, and ISC based on various input signals.
0, 120, 130, 150, 190, etc. are calculated and output, but the calculation method or correction data is changed depending on the engine state estimation data 3601.

Next, the operation shown in FIG. 6 will be explained in detail based on an actual example.

This example is an example in which a state where the engine is likely to stall is predicted from a change in engine rotational speed, and control is performed to avoid it.

FIG. 7 is a diagram showing the engine rotation pattern before and after the engine stalls.

In FIG. 7, section A is a deceleration section. When the clutch is disengaged at the end of deceleration, the load is reduced, so the engine speed increases once and then begins to decrease again. At this time, for example, parts of the engine's fuel supply system may have changed over time, and the fuel supply amount (mixture ratio)
If the clutch is not properly disengaged, the timing of the clutch disengagement is too late and the rotational speed drops too much, the ignition timing is not appropriate, or the area around the throttle valve is dirty and the air-fuel mixture is not stably supplied. In some cases, the engine does not stably converge to an idle state and a hunting phenomenon occurs,
The rotational speed gradually decreases (section B), and the engine may eventually stall (section C).

Here, for example, if we measure the rotation movement pattern in section D, judge whether it follows the pattern shown in the figure (pattern recognition), and determine that the pattern is likely to stall, that is, if the engine stalls. If it is estimated, if the engine load is reduced (for example, the air conditioner is stopped) at the end of section D and the surplus torque of the engine is increased,
It is possible to prevent the engine from stalling.

FIG. 8 shows a program 3150 executed by the CPU 1300 as the actual operation pattern measuring means 3100.
This is a flowchart.

This program is a regular interrupt program that is activated by an interrupt signal sent from the above-mentioned interval timer at regular intervals.

First, in 3151, it is determined whether it is a measurement section. The measurement section is, for example, section D in FIG. 7. This determination is made by determining deceleration based on the throttle opening and vehicle speed, determining the start of a section based on whether the engine speed has reached a predetermined value, and determining the end of the section based on whether a predetermined time has elapsed. It can be done. If it is within the measurement area, 3152
, sequentially sample the measured data.
It will be stored in RAM1430. By this,
Time series data of actual engine rotation is measured and stored as actual operation pattern data 3101.

Next, the operation of the operation change pattern creation means 3200 will be explained using an example of an operation when an air conditioner is turned on and off.

FIG. 9 is a diagram showing changes in engine rotation speed when the air conditioner is turned on and off.

It has been experimentally known that the engine speed changes as shown in the figure, depending on whether the air conditioner is turned on or off. This rotational change pattern is stored in advance as data, and for example, when the air conditioner switch is turned on, it is detected and the rotational speed changes from that time as shown in section A. Predict as.

Figure 10 shows operation change pattern data 320.
1 is a flowchart of a program 3250 for calculating 1. The microcomputer is stored in advance with pattern data of the change in rotational speed when the air conditioner is turned off (a value with the starting point of section A in Figure 9 as zero) and the pattern data of the change in rotational speed when the air conditioner is turned off (the The pattern data of the section in the figure) (a value with the starting point of B as zero) is stored. The program started with a scheduled interrupt determines from the air conditioner switch data whether or not the air conditioner is turned on at 3251, and if YES, at 3252,
Pre-stored pattern data of changes when the air conditioner is turned on is selected and outputted as operation change pattern data 3201. Similarly, when off, 3253 and 3254 select and output data when off.

Next, the operation of the predicted operation pattern synthesis means 3300 will be explained using an example in which the air conditioner is turned on during deceleration.

FIG. 11 is a diagram showing changes in engine rotational speed when the air conditioner is turned on during deceleration.

In FIG. 11, when the rotational speed is changing as shown in line a during deceleration, if the air conditioner is turned on at a point in time, the rotational speed changes as shown in line b. In this case, the rotational speed is high enough so that there is no need to worry about engine stalling. On the other hand, if the air conditioner is turned on at point c, the rotation speed will drop significantly and there is a strong possibility that the engine will stall.Figure 12 shows the rotation speed as explained above. This is a flowchart of a program 3350 that creates predicted motion pattern data 3301 for making predictions.

First, step 3351 is executed, for example, at the time point in FIG. 11, and is extrapolated from the actual operation pattern data 3101 at that time point to calculate the subsequent rotation change pattern. That is, the extension of line a is estimated, and this extrapolated data is used as a tentative predicted value.

3352 is the operation change pattern data 32.
01 is added to the extrapolated data. As a result, the predicted motion pattern data 33 such as b, c, etc.
01 is created. Note that if the change is gradual, it is sufficient to simply connect the operation change pattern data 3201 to the rotational speed at the time point without extrapolation. Furthermore, if there is no operation such as turning on or off the air conditioner, the operation change pattern data 3201 is zero, so the predicted operation pattern data 3301
becomes the actual operation pattern data 3101 itself. This applies to cases such as deceleration hunting shown in FIG.

Next, FIG. 13 is a flowchart of a program 3450 for creating actual state data 3401.

First, check the engine rotation speed with 3451, and if it is less than 20 rpm, check the data 34 with 3452.
Set 01 to data representing engine stall. If not, in step 3453, data 3401 and data indicating that the engine is rotating are changed. In addition to the engine rotation, intake air volume, oil pressure, etc. can also be used to determine whether the engine stalls. It is also possible to determine the actual state of the engine, such as acceleration and deceleration, from the movements of the throttle, intake air amount, etc.

Next, Figure 14 shows operation pattern data 3 by state.
35 is a flowchart of a program 3550 for creating 501.

First, the actual state data 3401 is checked in 3551, and if the engine is stalled, the immediately preceding actual operation pattern data 3101 (pattern data in section D in Fig. 7) is stored as the operation pattern data at the time of engine stall in 3552. do. This data is stored in a storage memory 1440 (see FIG. 5) so that it is retained even when the ignition switch 260 is turned off and the main power is turned off. As a result, the operating pattern of the engine rotation when the engine actually stalls while the engine is in use is stored.

In addition, in addition to the above-mentioned data, operation patterns when the engine stalls that occur in development experiments, etc. are prepared in advance by different driving pattern data 3501 when the engine stalls.
Let me remember it as. Specifically, it is stored in the mask ROM 1410, PROM 1420, etc. at the time of manufacturing the control device. Furthermore, by adding a similar program, it is also possible to store operation pattern data corresponding to engine conditions such as acceleration and deceleration.

Next, the operation of engine state estimating means 3600 will be explained.

Figure 15 shows the predicted movement pattern when the engine stalls.
Data 3301 and state-specific operation pattern data 3
501. FIG.

In FIG. 15, line a is data stored in the state-specific operation pattern storage means 3500, and is operation pattern data 3501 when the air conditioner is turned on during deceleration and the engine stalls. Actually, section B in the diagram is stored, but for the sake of clarity, sections A and C before and after it are stored.
The figure also shows how the engine rotates.

Line b is the predicted operation pattern synthesis means 3 for the case where the air conditioner is turned on at the time.
Predicted movement pattern data 3 created in 300
It is 301. Operation pattern data by status 35
Similar to 01, the state of rotation before and after is also illustrated.

The engine state estimating means 3600 is shown in the hatched part of the figure (the part surrounded by lines a and b in section B).
Find the area of Predict and judge what will happen.

Next, FIG. 16 shows the engine state estimation means 360
0 is a flowchart of a program 3650 for calculating engine state estimation data 3601.

First, in 3651, predicted motion pattern data 3
301, and the first pattern data 3501-1 among the plurality of stored state-specific operation pattern data 3501 (for example, this is the pattern data when the air conditioner is turned on during deceleration and the engine stalls). The difference at each time point (3301-35
01-1) is sequentially calculated and integrated over the entire section B. As a result, the difference area data between lines b and a in FIG. 15 is calculated with a sign. This difference area data is compared with a predetermined value at 3652. If it is larger than the predetermined value, line b (predicted rotational movement pattern) is relatively above line a (rotational movement pattern when engine stalling actually occurs), and there is no risk of engine stalling. If it is smaller than the predetermined value, line b is relatively close to line a or below line a, and there is a strong risk of engine stalling, so it is determined that engine stalling will occur, and 3653
Then, the engine state estimation data 3601 is changed to data representing engine stalling.

Below 3654 and 3655, similar processing is performed on the second and third (for example, pattern data at the time of engine stall due to deceleration hunting in FIG. 7) engine state-specific driving pattern data.

From this, it is estimated that the rotational speed matches the rotational movement pattern that caused the engine to stall, or that the rotational speed becomes relatively lower than that and the engine stalls.

In this example, since we are only determining whether the engine is stalled, the difference is determined with a sign, and only whether the engine is stalled or not is determined. By integrating the absolute values, calculating and comparing the area itself, and setting the engine condition estimation data to different values according to the results, it is possible to identify which of the multiple operating patterns it matches or approximately matches. can. Even in the case of engine stalling, there are multiple patterns, so it is possible to identify which state the engine is in.

Next, FIG. 17 is a flowchart showing a part of a program 3750 executed as the control output calculation means 3700.

This program is rotationally synchronous, that is, a signal (REF
This is a program that is activated by an interrupt signal (signal 201).

First, in 3751, engine state estimation data 36
01 to determine whether the engine is estimated to be stalled. If it is determined that the engine will not stall, normal control is performed at 3752. For normal control content, please refer to the SAE paper mentioned above.
800056, 800825, etc. are well known, so their description will be omitted.

If it is estimated that the engine has stalled, the air conditioner is stopped at 3753 to reduce the load on the engine.

In engine stall avoidance control, the above-mentioned method of turning off the air conditioner to lighten the load on the engine to generate surplus torque has a faster response and is advantageous compared to methods such as increasing engine speed.

In addition to stopping the air conditioner, there are various methods for reducing the load on the engine, such as those listed below. Any one or a combination of two or more of these methods may be used.

(1) A method of reducing the amount of power generated by the generator (alternator) that is directly connected to the engine. Specifically, the field current of the alternator is cut off using a relay or the like.

(2) As a method of indirectly reducing load torque, electric loads such as heaters (fans and motors),
Turn off the power to devices that can be turned off without causing any problems in an emergency, such as the rear window heating wire, radio, and stereo. Specifically, a relay is installed in the power supply circuit to control it. In addition, these power supply systems have 1
It is sufficient to insert several relays.

(3) There are some electrical loads that pose a problem if turned off completely, but are not a problem if the power supply current is slightly reduced, such as headlamps and wipers.

These can reduce the power supply current by intermittent power supply and duty control.

In addition to the method for estimating engine stalling as described above, a conventional method of predicting engine stalling that simply predicts engine stalling based on the instantaneous value of engine rotation is also effective as a method for reducing engine load.

Further, as described above, the method of reducing the load on the engine and the method of increasing the torque generated by the engine may be used together.

Methods for increasing the torque generated by the engine include increasing the amount of intake air, advancing the ignition timing, increasing the ignition energy (increasing the energization time to the ignition coil),
There are methods such as reducing EGR and controlling the mixture ratio in the direction of increasing torque.

The method of increasing the generated torque as described above is as follows:
Since the response is slower than the above-mentioned method of reducing the load, there is a risk that this method alone will not be enough to avoid engine stalling, but if both are used together, engine stalling can be more reliably avoided.

〔Effect of the invention〕

As explained above, according to the present invention, an engine stall can be reliably avoided with good responsiveness by predicting an engine stall and immediately reducing the engine load to generate surplus torque in that case.

[Brief explanation of drawings]

Fig. 1 is an example of a conventional device, Fig. 2 is a corresponding diagram of the control system of the device in Fig. 1, Fig. 3 is a block diagram showing the overall configuration of the present invention, and Fig. 4 is an electronic control system of the present invention. The overall configuration of the device, Figure 5 shows the control and
A circuit configuration diagram of the unit 1000, FIG. 6 is a block diagram showing an embodiment of a control system to which the present invention is applied,
Figure 7 is a diagram showing the engine rotation pattern before and after the engine stalls, Figure 8 is a flowchart of the program executed by the CPU as a means of measuring the actual operation pattern, and Figure 9 is the change in engine rotation speed when the air conditioner is turned on and off. FIG. 10 is a flowchart of a program that calculates the operation change pattern data 3201. FIG. 11 is a diagram showing changes in engine speed when the air conditioner is turned on during deceleration. FIG. 12 13 is a flowchart of a program that creates predicted motion pattern data 3301, FIG. 13 is a flowchart of a program that creates actual state data 3401, and FIG. 14 is a flowchart of a program that creates state-specific motion pattern data 3501. FIG. 15 is a diagram showing the relationship between predicted operation pattern data 3301 and state-specific operation pattern data 3501 at the time of engine stall, and FIG. 16 is a diagram showing the relationship between engine state estimation data 360.
17 is a flowchart of a program 3650 for calculating 1. FIG. 17 is a flowchart of a program executed as the control output calculating means 3700. Explanation of symbols 20...sensor group, 21...prediction means, 22...control means.

Claims (1)

[Scope of Claims] 1. A sensor for detecting the operating state of the engine and auxiliary machinery; and a first means for inputting signals from the sensor and storing data within a predetermined period as time-series data of engine rotational speed. , detecting a predetermined condition that is known in advance to cause a change in engine operation from the signal of the sensor;
a second means for outputting data on changes in the engine rotational speed that occur when the state is reached; and a provisional predicted value of the future engine rotational speed is calculated based on the time series data of the first means; a third means for predicting future engine rotational speed data by combining the data of the second means; and a preset engine rotational speed data predicted by the third means. a fourth means for predicting the occurrence of an engine stall by comparison with a pattern or value that is expected to cause a stall; and a fifth means for reducing the engine load when the fourth means predicts the occurrence of an engine stall. An electronic engine control device having an engine stall avoidance function, characterized in that it is equipped with means for preventing an engine stall. 2. Claim 1, wherein the fifth means reduces the engine load by stopping or reducing the load on auxiliary machinery that is mechanically driven by the engine. An engine electronic control device having an engine stall avoidance function as described in . 3. The engine electronics having an engine stall avoidance function according to claim 1, wherein the fifth means reduces the engine load by stopping or reducing the electrical load. Control device. 4. The engine stall according to claim 3, wherein the fifth means stops or reduces the electrical load by duty-controlling the electric power supplied to the electrical load. Engine electronic control unit with avoidance function.