JPH06100145B2 - Engine state estimation device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates mainly to an electronic control unit for controlling the fuel supply amount, injection timing, intake air amount ignition timing, etc. of an automobile engine such as an internal combustion engine, The present invention relates to a technique for performing precise control by storing an operating state.

[Prior art]

2. Description of the Related Art As a conventional total engine electronic control unit, there is one shown in FIGS. 1 and 2, for example.

The above-mentioned device is described in SAE Paper 800056 and 8008, and 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, 3 is an AAC valve that adjusts the intake air amount to control the idle rotation speed, 4 Controls the exhaust gas recirculation amount. EGR control valve, 5 is a negative pressure converter (composite of constant pressure valve and on / off solenoid valve) that controls the opening of AAC valve 3 and EGR control valve 4, 6 is a fuel injection valve, 7 is an oxygen sensor, 8 Is an ignition il, 9 is a distributor, 10 is a three-way catalyst, 11 is an exhaust temperature sensor, 12 is a neutral switch for detecting the neutral position of the transmission, 13 is a crankshaft sensor for detecting the rotation angle of the crankshaft, and 14 is cooling. Water temperature sensor,
Reference numeral 15 is a fuel pump, 16 is a fuel pump relay, 17 is a vehicle speed sensor, and 18 is an air conditioner switch.

In the above-mentioned device, input signals from various sensors as shown in FIG. 2 are input to a microcomputer (not shown) to comprehensively control various actuators as shown.

The control contents of the above-mentioned device are as follows.

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

(2) Control of air supply (ISC) that keeps the engine speed constant during idling.

(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, the conventional device described above does not have a function of storing and holding the operating state of the engine, and therefore has the following drawbacks.

That is, (1) when a defective phenomenon such as engine stall occurs, it cannot be effectively prevented from recurring. (2) To know the degree of change in engine characteristics (for example, the degree of change over time). (3) When an engine malfunction occurs, the cause cannot be diagnosed effectively.

[Object of the Invention]

The present invention has been made to solve the problems of the prior art as described above, and stores and holds the operating state of the engine as time series pattern data, and reflects the result in the control and diagnosis of the engine. It is an object of the present invention to provide an engine state estimation device capable of performing the above.

[Outline of Invention]

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

In FIG. 3, reference numeral 20 denotes an operating state of the engine and auxiliary devices (transmission, air conditioner, etc.) (in the case of an engine used in a vehicle, the state of the vehicle, for example, the vehicle speed is also included, which will hereinafter be collectively referred to as the engine operating state) Various sensor groups (20 in Fig. 4 below)
0, 210, 220, 230, 250, 270, 280, etc.), 21 is arithmetic means for performing various arithmetic operations for control and diagnosis, 22 is various actuators and display means which operate according to the arithmetic result of the arithmetic means 21 (described later). 32, 38, 41, 42, 60, 70, 80, etc. in FIG. 4).

Further, 23 is an actual operation pattern measuring means, which samples the operation signal of the engine given from the sensor group 20 at a predetermined cycle and stores sampling data for a predetermined period as time-series pattern data.

Reference numeral 24 is an actual state determination means that determines from the output of the sensor group 20 that the engine state has reached a predetermined state (a plurality of states are possible).

Reference numeral 25 is an operation pattern storage means for each state, and the actual state determination means 24 has a predetermined engine state (for example, a stall state).
Actual operation pattern measuring means when it is determined that
The value stored by 23 is stored as operation pattern data corresponding to the predetermined engine state.

The calculation means 21 performs calculation based on the operation signal of the engine given from the sensor group 20 and the operation pattern data output by the operation pattern storage means 25 for each state, controls the actuator and the display means 22, and displays Make an action. It is also possible to perform fault detection and self-diagnosis of control status.

Example of Invention

 Hereinafter, the present invention will be described in detail based on examples.

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

FIG. 4 shows a case where the present invention is applied to a 4-cycle 6-cylinder engine, and the control target is as follows.

(1) Injector 35 provided in each cylinder of the engine
Fuel injection (EGI) control (EGI OUT 110) is performed by controlling the valve opening start time and valve opening time.

(2) Ignition (IGN) control (IGN OUT 120) that controls the ignition timing and energization time by controlling the energization / interruption of the primary coil of the ignition coil 38.

(3) Exhaust gas recirculation (EGR) control (EGR OUT 130) performed by negatively controlling the lift amount of the EGR valve 30 using the VCM valve 40.

(4) By controlling the negative pressure of the lift amount of the AAC valve 50 using the VCM valve 40, the idle rotation (IS which is performed by controlling the amount of air that bypasses the throttle valve 510)
C) Control (ISC OUT 150).

While the above is the main control target, there are the following as other incidental control or information output. (5)
ON / OFF control of the fuel pump 530 by controlling the fuel pump relay 60 (F / P OUT 160), (6) Output of fuel consumption data to the fuel consumption meter 70 (FCM OUT 170), (7)
System self-diagnosis and data exchange (CHECK) with checker 2000 or vehicle information providing device 2500, (8) Output of alarm by alarm result to alarm lamp 80 (ALAR
M OUT 180), (9) Display (MONIT) of self-diagnosis results on the display 1900. (10) Control by the air conditioner control signal (A / COUT 190) to the air conditioner relay 90 that turns on / off the air conditioner (air conditioner) (AIR CO
N).

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

(1) From the crank angle sensor 200 built in the distributor 520, the REF signal 201 rising every 120 ° at the rotation angle of the crankshaft (twice the rotation angle of the distributor).
And POS signal 202 where rising and falling alternately occur every 1 °
To get

An engine speed signal 203 is obtained by counting the POS signal 202 for a predetermined time.

(2) The engine intake air amount Q _a is an air flow meter
It detects by 210. Note intake air amount Q _a is made inversely related to the air flow meter output voltage signal (AFM) 211.

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

(4) The water temperature sensor 230 obtains a voltage signal (T _W ) 231 representing the temperature of the engine.

(5) The on-vehicle battery 240 supplies electricity to each part of the control system. Control to the control unit 1000
Main power supply 241 via unit relay 540 and battery 24
The auxiliary power supply 242 which is directly input from 0 is supplied. The voltage signal (V _B ) 241 of the main power source is also used as information for control. The ON terminal 262 of the ignition switch 260 is
Since the battery voltage is applied not only in the ON position but also in the START position, the control unit 10 can be used during cranking.
The main power supply 241 is supplied to 00.

(6) The vehicle speed sensor 250 obtains a signal (VSP) 251 having a pulse density proportional to the vehicle speed.

(7) The ignition switch 260 is a switch operated by the driver to start and drive the engine.
The voltage signal (START) 261 at the T terminal makes it possible to know whether cranking is in progress.

(8) Throttle valve sensor 270 uses throttle opening signal (TVO) 271 proportional to the opening of the throttle valve.
Is output.

(9) The air conditioner switch 280 is a switch that closes when the air conditioner is operated, and detects whether the air conditioner is operating by the terminal voltage signal (A / C) 281.

(10) Neutral switch 290 is a switch that closes when the gear position of the transmission is in neutral or in the parking position, and its opening / closing signal (NEUT) 29.
1 detects the gear position of the transmission.

The signals described above are input to and output from the control unit 1000. In addition to the input / output to / from the control unit 1000, a checker 2000 for diagnosing the control system and displaying the result is connected via a checker connector 2010. Further, the vehicle information providing device 2500 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 control information (input signal) and outputs a control signal (output signal) to optimally control the engine and Output information related to.

Functions such as 21, 23, 24 and 25 in FIG. 3 are included in the control unit 1000.

Next, a control that comprehensively performs the control described above.
The circuit configuration of the unit 1000 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 causes malfunction of the control unit 1000 due to noise. In addition to preventing damage due to surges, various input signals are amplified or converted so that the next input interface circuit 1200 can be properly operated. 1200 is an input interface circuit, which performs analog-digital (AD) conversion of various input signals shaped by the signal shaping circuit 1100,
The number of pulses during a predetermined time is counted, converted into a digital code signal so that the next central processing unit (CPU) 1300 can read it as input data, and stored in an internal register as input data. 1300 is a central processing unit (CPU), which is an oscillation signal 1311 of a crystal oscillator 1310.
It operates in synchronization with a clock signal based on
It is connected to each part via 20 and mask ROM 141 of memory 1400
0 and the program stored in PROM1420 are executed, various input data are read from each register in the input interface circuit 1200, various output data are calculated and calculated, and predetermined timing is set in the register in the output interface circuit 1500. To send output data. memory
1400 is a data storage device, which includes a mask ROM 1410 and a PROM 142.
0, RAM 1430 and memory holding memory 1440. The mask ROM 1410 permanently stores the program executed by the CPU 1300 and the data used when executing the program when the IC is manufactured, and the PROM 1420 has the same program and data as the mask ROM 1410 that is highly likely to be changed according to the vehicle type and engine type. Is permanently written and stored before being incorporated into the control unit 1000. Further, the RAM 1430 is a readable / writable memory, which stores data that is temporarily stored in the output interface circuit 1500 before being sent to the output interface circuit 1500 as data during calculation processing or result data, and this memory content is stored in the ignition switch 260. When the power is turned off and the main power supply 241 is turned off, it is not held. In addition, the memory holding memory 144
0 indicates that the result data of the arithmetic processing and the intermediate data are stored and retained even when the ignition switch 260 is turned off, that is, when the automobile is not driven.

1350 is an arithmetic timer circuit, which enhances the functions of the OPU 1300, a multiplication circuit for speeding up arithmetic processing, an interval timer that sends an interrupt signal to the CPU 1300 at predetermined time intervals, a CPU 1300 Has a free-run counter or the like for knowing the elapsed time from a predetermined event to the next event and the event occurrence time. An output interface circuit 1500 receives output data from the CPU 1300 in a register having contents, converts it into a pulse signal having a predetermined timing and time width, or a predetermined cycle and duty ratio, or outputs “1” or “0”. Is converted to a switching signal and sent to the drive circuit 1600. The drive circuit 1600 is a power amplification circuit, which receives signals from the output interface circuit 1500 and performs voltage / current amplification with a transistor or the like to drive various actuators, display, or a connector to the control unit 1000. It is connected through 2010 to perform diagnosis of the control system and send an output signal to the checker 2000 for displaying the result.

1700 is a backup circuit, which monitors the signal from the drive circuit 1600 to detect a failure, and when the CPU 1300, memory 1400, etc. fails and does not operate normally, the signal shaping circuit 11
Receiving a part of the signal from 00, the engine outputs the minimum necessary control output for driving the vehicle, and the switching signal 1701 for notifying the occurrence of a failure. 1750 is a switching circuit, and a switching signal from the backup circuit 1700
The signal from the output interface circuit 1500 is blocked by 1701 and the signal from the backup circuit 1700 is passed.

1800 is a power supply circuit, which has a stable power supply voltage of 181
Supply 0, 1820, 1860, 1880, 1890 and CPU 130
It outputs a RESET signal 1840, a HALT signal 1850, a battery voltage signal 1830, etc. that control the operation of 0.

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

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

The overall configuration and schematic operation will be described below.

First, the actual operation pattern measuring means 3100 uses various input signals 20
Input 3, 211, 271, etc., sample for each predetermined interval for a predetermined period, store them sequentially, and see what kind of operation pattern the engine speed, intake air amount, throttle opening, etc. are. The actual operation pattern data 310 is stored in the form of pattern data.

On the other hand, various input signals 281 and 291 are also input to the operation change pattern creating means 3200, and operation pattern data predicted as changes in the engine speed, intake air amount, etc. are selected according to the movement of the signals. The motion change pattern
Output as data 3201.

The predicted motion pattern synthesizing means 3300 inputs the actual motion pattern data 3101 and the motion variation pattern data 3201, synthesizes and processes both, and future rotation, intake air amount,
Predicted operation pattern data 3301 that predicts what the operation pattern of the throttle, etc. will be, is created. Predicted motion pattern data 3301 when the motion change pattern is zero
Is the same as the actual operation pattern data 3101.

The actual state discriminating means 3400 has various input signals 203, 211, 231, 2
From 71, 281, 291, etc., an engine state, for example, an unsteady state such as engine stall (engine stall), acceleration, deceleration, gear change, etc. is determined, and actual state data 3401 is output.

The operation pattern storage means 3500 for each state stores the actual state data 3401.
According to the above, the actual operation pattern data 3101 such as rotation, intake air amount, throttle opening, etc. when the engine state occurs are stored as state-specific operation pattern data 3501 by distinguishing each engine state.

As described above, the state-specific operation pattern data 3501 includes not only the actual operation pattern data 3101 generated while the engine is in use and stored, but also data that is stored in advance when the control device is manufactured.

The engine state estimating means 3600 uses the predicted operation pattern
The data 3301 and the operation pattern data 3501 by state are compared and collated, and when they match or approximately match, it is estimated that the engine state is the engine state corresponding to the matched operation pattern data by state The state estimation data 3601 is output.

The control output computing means 3700 uses the EGI, I
Control output of GN, EGR, ISC, etc. (110, 120, 130, 150, 190
Etc.) is calculated and output, but the calculation method or correction data is changed according to the engine state estimation data 3601.

In the embodiment of FIG. 6, the predicted operation pattern synthesizing means 3300, the engine state estimating means 3600, etc. are also included, but the present invention is at a minimum, the actual operation pattern measuring means 3100, the actual state discriminating means. 3400 and the operation pattern storage means 3500 for each state.

That is, the engine state can be estimated based on the stored operation pattern data for each state, and the engine can be controlled according to the result, but it can also be applied to failure diagnosis and detection of changes in engine characteristics over time.

That is, the operation pattern for each state that is stored and held.
By using the data, for example, after an engine stall occurs, the data can be displayed or read and checked to find out the engine operation at the time of engine stall, which is effective data for investigating and estimating the cause of engine stall. .

Next, the operation of FIG. 6 will be described in detail based on an example.

This example is an example in which a state in which engine stalling is likely to occur is predicted from a change in engine speed, and control is performed so as to avoid it.

FIG. 7 is a diagram showing a pattern of engine rotation before and after engine stall.

In FIG. 7, the section A is a deceleration section. When the clutch is disengaged at the end of deceleration, the load decreases and the engine speed increases once and then starts decreasing again. At this time, for example, parts of the fuel supply system of the engine are changing over time, the fuel supply amount (mixing ratio) is not appropriate, the timing to release the clutch is late and the drop in rotation speed is too large, the ignition timing is If the mixture is not appropriate or if the throttle valve is dirty and the mixture is not supplied stably, the engine will not stably converge to the idle state and a hunting phenomenon will occur and the rotation speed will gradually increase. It may decrease (section B) and finally reach engine stall (section C).

Here, for example, when the rotation operation pattern in the section D is measured and it is judged whether or not the pattern is as shown in the figure (pattern recognition), and it is judged that the pattern is likely to stall, that is, the stall Is estimated, increase the amount of air-fuel mixture at the end of section D,
By increasing the torque generated by the engine, it is possible to prevent engine stalling.

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

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

First, in 3151, it is judged whether or not it is a measurement section. The measurement section is, for example, the section D in FIG. This determination is performed by determining deceleration based on the throttle opening and the vehicle speed, determining the start of the section depending on whether the engine speed reaches a predetermined value, and determining the end of the section depending on whether a predetermined time has elapsed. If it is within the measurement section, the measured data is sequentially sampled at 3152 and stored in the RAM 1430. As a result, the actual engine rotation pattern is measured and stored as the actual operation pattern data 3101.

Next, the operation of the operation change pattern creating means 3200 will be described by taking the operation when the air conditioner is on / off as an example.

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

It is experimentally known that the engine speed changes as shown in the figure depending on whether the air conditioner is on or off. This rotation change pattern is stored in advance as data,
For example, if the air conditioner switch is turned on,
This is detected, and it is predicted that the rotation speed changes as shown in the section A starting from that time.

FIG. 10 is a flowchart of the program 3250 for calculating the movement change pattern data 3201. The microcomputer previously stores the pattern data of the change in the rotation speed when the air conditioner is on (a value in which the starting point of the section A in FIG. 9 is zero) and the change in the rotation speed when the air conditioner is off (the ninth value). (Value with the starting point of section B in the figure set to zero)
Data and are stored. The program started by the timed interrupt judges from the data of the air conditioner switch whether the air conditioner is turned on in 3251, and if YES, it is stored in 3252 when the air conditioner is stored in advance. Minute pattern data is selected and output as motion change pattern data 3201. At the same time, at the time of off, the data at the time of off is selected and output by 3253 and 3254.

Next, the operation of the predictive operation pattern synthesizing unit 3300 will be described by taking the case where the air conditioner is turned on during deceleration as an example.

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

In FIG. 11, when the air conditioner is turned on at the time when the rotation speed is changing as shown by line a during deceleration, the rotation speed changes as shown by b. In this case, the rotation speed is sufficiently high and there is no fear of engine stall. On the other hand, when the air conditioner is turned on at that time, it changes like c, and the rotation speed is significantly reduced, and there is a strong possibility that the engine will stall.

FIG. 12 is a flowchart of the program 3350 for creating the predicted motion pattern data 3301 for predicting the rotation as described above.

First, 3351 is executed, for example, at the time point in FIG. 11, and extrapolation is performed from the actual operation pattern data 3101 at that time point, and the subsequent rotation change pattern is calculated. That is, line a
Estimate the extension of.

In 3352, the movement change pattern data 3201 is added to the extrapolation data. As a result, predicted motion pattern data 3301 such as b and c is created. If the change is gradual, extrapolation may not be performed, and the motion change pattern data 3201 may simply be connected to the rotation speed at the time. If there is no operation such as air conditioner on / off,
Since the motion change pattern data 3201 is zero, the predicted motion pattern data 3301 is the actual motion pattern data 3101.
Become itself. This corresponds to the case of deceleration hunting in FIG.

Next, FIG. 13 shows a program 34 for creating the actual state data 3401.
It is a flowchart of 50.

First, at 3451, the engine speed is checked, and if it is 20 rpm or less, at 3452, the data 3401 is changed to data indicating engine stall. Otherwise, at 3453, the data 3401 is changed to data indicating that the engine is rotating. In addition to the engine rotation, the intake air amount, hydraulic pressure, etc. can be used for the engine stall determination. It is also possible to determine the actual state of the engine such as acceleration / deceleration from the movements of the throttle and the intake air amount.

Next, FIG. 14 is a flowchart of the program 3550 for creating the operation pattern data 3501 for each state.

First, the actual state data 3401 is checked at 3551, and if it is an engine stall, at 3552, the actual operation pattern data 31 immediately before that is checked.
01 (pattern data of section D in FIG. 7) is stored as operation pattern data at the time of engine stall. This data is stored in the memory holding memory 1440 (see FIG. 5) so that the memory is held even if the ignition switch 260 is turned off and the main power is turned off.

As a result, the operation pattern of the engine rotation when the engine actually stalls during use of the engine is stored.

In addition to the above data, the operation pattern at the time of engine stall that has occurred in a development experiment or the like is stored in advance as another operation pattern data 3501 at the time of engine stall. Specifically, mask ROM 1410, PROM 1420 when manufacturing the control device
Etc. Further, it is possible to store operation pattern data according to the state of the engine such as acceleration and deceleration by adding a similar program.

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

Figure 15 shows predicted motion pattern data 3301 at the time of engine stall.
FIG. 5 is a diagram showing a relationship between state-based operation pattern data 3501.

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

The line b is the predicted motion pattern data 3301 created by the predicted motion pattern synthesizing means 3300 when the air conditioner is turned on at that time. Similar to the operation pattern data 3501 for each state, the state of rotation before and after that is also illustrated.

The engine state estimating means 3600 obtains the area of the hatched portion (the portion surrounded by the lines a and b of the section B) in the figure, and depending on whether the size is larger or smaller than a predetermined value, if left as it is, the engine will stall. If it is smaller than a predetermined value, it is predicted that the engine state will reach engine stalling.

Next, FIG. 16 is a flowchart of a program 3650 in which the engine state estimating means 3600 calculates the engine state estimation data 3601.

First, in 3651, the pattern data 3501-1 of the predicted operation pattern data 3301 and the plurality of stored state-based operation pattern data 3501 (for example, the pattern when the engine is turned on and stalled during deceleration) -The difference (3301-3501-1) of (data) at each time point is sequentially calculated and integrated over the entire section B. By this,
The difference area data between the 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, the line b (predicted rotation operation pattern) is relatively above the line a (rotation operation pattern when the engine actually stalls), and there is no risk of stall. If it is smaller than the predetermined value, the line b is relatively close to the line a or is below the in a, and there is a strong possibility of stalling, so it is determined that stalling will occur.
Then, the engine state estimation data 3601 is changed to data indicating engine stall.

In 3654 and 3655 or less, the same processing is performed on the second and third (for example, the pattern data at the time of engine stall due to deceleration hunting in FIG. 7 etc.) engine state-specific operation pattern data.

As a result, it is presumed that the engine stalls if it coincides with the rotational motion pattern that has reached the engine stall up to now, or if the rotational speed becomes relatively lower than that.

In this example, since only the engine stall is determined, the difference is obtained with a sign, and the determination is made only as to whether the engine is stall or not.However, when identifying engine states other than engine stall, such as acceleration and deceleration, the difference of If the engine state estimation data is set to different values according to the result by calculating the area itself by integrating the absolute values and comparing the areas, it is possible to identify which of a plurality of operation patterns is matched or approximately matched. . Even in the case of stalling, there are multiple patterns, so it is possible to identify which state of stalling.

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

This program is rotation synchronous, that is, the crank angle sensor 200
Is a program started by an interrupt signal by a signal (REF signal 201) for every 120 ° crank angle.

First, at 3751, the engine state estimation data 3601 is checked to determine whether it is presumed to be stalled. If it is determined that the engine has not reached the stalling, the normal control is performed at 3952. For the normal control contents, see SAE Paper 800 above.
Since it is well known in 056, 800825, etc., it will be omitted. If the engine is estimated to be stalled, the air amount (that is, the air-fuel mixture amount) by the ISC is increased at 3753, and the rotational torque is controlled to increase. Specifically, there is a method of increasing the control target speed of ISC and indirectly increasing the air amount in feedback control, and
A method of directly increasing the air amount by feedforward control for the control output of C can be applied, but the latter has better responsiveness. However, with the latter method, it is not possible to strictly control how much the rotation speed increases, so if you want to keep the increase width constant, control with feedforward for a short time and gradually shift to feedback. You should take.

In 3754, the ignition timing is corrected in the direction in which the torque increases, that is, in the direction in which the torque advances.

In some cases, the engine may be stalled easily due to lack of ignition energy. Therefore, it is also effective to increase the ignition energy, that is, control the time for energizing the ignition coil.

With the 3755, the EGR is reduced and the combustion condition is improved.

In addition to this, in order to prevent engine stalling, control such as controlling the mixture ratio of the air-fuel mixture in the direction of increasing torque (EGI control) or reducing the load on the engine (for example, turning off the air conditioner) is also effective.

Although the above description has been given of an example of predicting and avoiding engine stall, the present invention can also be applied to detection of acceleration / deceleration, gear change, and the like. It is also possible to use operation data other than the rotation speed, for example, an intake air amount signal (AFM signal 211), a throttle opening signal (TVO signal 271) and the like.

These will be described below.

For example, regarding a gear change, the presence or absence of a gear change can be detected by detecting the operation of a clutch or the like, but it is not possible to distinguish which gear change from what speed. In order to make a distinction, a complicated sensor for identifying all gear positions is required, which is expensive and complicated. However, by applying the method of the present invention, detecting the change pattern of the intake air amount, throttle opening, engine rotation, etc., and comparing it with the pattern data that has been experimentally measured in advance and stored at the time of manufacture, Accurately and quickly estimate if a gear change has occurred. Then, by adding the result to the control, the control suitable for each engine state can be performed. As an example, a method of controlling the fuel supply pattern according to the gear change pattern so as to minimize the emission of harmful components of the exhaust gas can be considered.

Also, regarding acceleration and deceleration, it is possible to estimate not only the determination of acceleration or deceleration but also the identification of acceleration / deceleration on a slope (individually up and down) and the degree of acceleration / deceleration.

This enables fine control of fuel, ignition, and EGR to reduce the emission of harmful components of exhaust gas.

Next, FIG. 18 is a flowchart of another program 3560 for creating the operation pattern data 3501 for each state.

In this case, the actual state determination means 3400 distinguishes not only whether the engine is stalled or not, but also whether the engine is stalled by turning on the air conditioner. Whether or not the air conditioner is turned on can be easily checked by checking whether or not the air conditioner is turned on immediately before the engine stall.

First, at 3561, it is checked by the actual state data 3401 whether the engine is stalled. Next, in 3562, air conditioner
Check whether the engine is stalled by turning on. If the answer is NO, proceed while checking whether the engine status is different in the same way. In the case of engine stall by turning on the air conditioner
Continue to 3563. In the 3563, the point data of the operation pattern data 3501-1 by state at the time of engine stall due to the air conditioner being turned on, which is already stored, and the point data of the actual operation pattern data 3101 measured this time are added together. Halve and find the average value (find the average value at each time point)
The pattern data of the average value is stored as operation pattern data for each state at the time of engine stall due to new air-conditioner on.

As a result, the pattern data is updated by half, so even if the abnormal actual operation pattern data 3101 is measured slightly due to noise, etc., the effect can be softened and the accurate operation state I can remember.
By weighting and averaging, it is possible to update at an arbitrary ratio such as 1/4 and 1/8. If the ratio is small, the influence of noise or the like can be reduced, but the data update speed becomes slow.

In the above embodiments, the engine state is estimated based on the stored operation pattern data for each state,
I explained an example of controlling the engine according to the result,
The present invention can also be applied to failure diagnosis and detection of changes in engine characteristics over time.

That is, the operation pattern for each state that is stored and held.
By using the data, for example, after an engine stall occurs, the data can be displayed or read and checked to find out the engine operation at the time of engine stall, which is effective data for investigating and estimating the cause of engine stall. .

Further, in the same engine state, it is also possible to determine a change in engine characteristics by storing and holding a plurality of data having different generation times and analyzing the difference.

〔The invention's effect〕

As described above, according to the present invention, when a problem such as engine stall occurs, the operation pattern of the engine at that time is stored, and when a similar operation pattern occurs again, by checking the coincidence, It can be estimated in advance that the same defect will reoccur, and recurrence can be effectively prevented.

It is also possible to effectively diagnose the cause of engine failure. Also, there are many excellent effects such as the degree of change in engine characteristics over time can be judged.

[Brief description of drawings]

FIG. 1 is an example of a conventional device, FIG. 2 is a corresponding diagram of a control system of the device of FIG. 1, FIG. 3 is a block diagram showing the overall configuration of the present invention, and FIG. 4 is an electronic control of the present invention. 5 is an overall configuration diagram of the apparatus, FIG. 5 is a circuit configuration diagram of the control unit 1000, FIG. 6 is a block diagram showing an embodiment of a control system to which the present invention is applied, and FIG. 7 is a diagram showing engine rotation before and after engine stall. FIG. 8 shows a pattern, and FIG. 8 is a flowchart of a program executed by the CPU as an actual operation pattern measuring means.
FIG. 9 is a diagram showing changes in the engine rotation speed when the air conditioner is turned on and off, and FIG. 10 is a flowchart of a program for calculating operation change pattern data 3201.
The figure shows the change in engine speed when the air conditioner is turned on during deceleration. Figure 12 is the flowchart of the program that creates the predicted motion pattern data 3301.
Figure is a flow chart of the program that creates the actual state data 3401, Figure 14 is a flow chart of the program that creates the state-specific operation pattern data 3501, and Figure 15 is the predicted operation pattern data 3301 at the time of stall and the operation pattern by state. FIG. 16 is a flowchart showing a relationship with data 3501, FIG. 16 is a flowchart of a program 3650 for calculating engine state estimation data 3601, FIG. 17 is a flowchart of a program executed as the control output computing means 3700, and FIG. It is a flow chart of another program which creates pattern data. Explanation of symbols 20 …… Sensor group, 21 …… Computing means 22 …… Actuator or display means 23 …… Actual operation pattern measuring means 24 …… Actual state determination means 25 …… State-specific operation pattern storage means

Claims (2)

[Claims] 1. A sensor for detecting an operating state of an engine or an operating state of an engine and auxiliary equipment, and sampling data of the sensor output for sampling data for a predetermined period corresponding to an actual operation of the engine at a continuous time. First means for storing as actual operation pattern data of a series, and second means for detecting from the output of the sensor that the actual engine state has reached a preset predetermined engine state
And the value stored in the first means when the second means determines that the engine is in a predetermined engine state, as operation pattern data corresponding to the predetermined engine state. 3 means and the actual operation pattern data measured and stored by the first means in the actual operation state and the operation pattern data in the predetermined state stored in the third means are compared and collated, An engine state estimation device comprising: a fourth means for estimating whether or not the engine state at that time is the predetermined engine state. 2. The state of the engine according to claim 1, wherein the third means retains the stored contents even when the engine is stopped with the ignition switch turned off. Estimator.