JPS6098135A - Electronic engine controller having engine stall avoiding function - Google Patents

Abstract

PURPOSE:To avoide engine stall by predicting engine stall through sensors for detecting the operating condition of engine or auxiliary machineries and reducing the engine load immediately. CONSTITUTION:Engine rotation speed signal 203, suction air flow Qa, signal 221 corresponding with air/fuel ratio, voltage signal 231 indicating the engine temperature, car speed signal 251 and throttle opening signal 271 are provided from crank angle sensor 200 incorporated in distributor 520, air flow meter 210, O2 sensor 220, water temperature sensor 220, car speed sensor 250 and throttle valve sensor 270 to a control unit 1000. The control unit comprising a microcomputer will determine the controlling state of each object to produce a signal thus to control the engine optimally while to produce information concerning to control.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to an electronic control device that mainly controls the fuel supply amount, injection timing, intake air amount, ignition timing, etc. of an automobile engine, such as an internal combustion engine. -Relates to technology that predicts the occurrence of stalls and avoids them.

[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-mentioned apparatus is described in SAJA1-Par 8 [10D56 and 800825, 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 the engineering flow for detecting the amount of intake air.
2 is a throttle position switch that detects when the throttle valve is fully closed; 6 is an AAC valve that adjusts the amount of intake air to control the idle rotation speed; 4 is an E G t (control pulp) that controls the amount of exhaust gas recirculation; 5 is AAC valve 6
A negative pressure converter (
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 gear shift 211 tral switch for detecting the neutral position of the machine, 1
6 is a crankshaft sensor that detects the rotation angle of the crankshaft, 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 a near conditioner switch.

In the above device, input signals from various sensors as shown in Fig. 2 are inputted to a microcontroller (not shown) to comprehensively control various actuators shown in the figure. .

The control contents of the above device are as follows.

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

(2) Air supply amount control (ISC) that keeps the engine speed constant at idle.

(5) 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 conventional devices such as those 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. My sister was in trouble.

In addition, 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 response of the engine is not very fast, there is a problem in 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 the present invention predicts the occurrence of engine stall from the operating state of the engine, etc., and controls the engine to reduce the engine load in that case. The purpose of the present invention is to provide an engine electronic control device that avoids this.

As mentioned above, when engine stall is predicted, start immediately;/
By reducing the load, surplus torque can be generated quickly, so engine stalling can be effectively avoided.

[Summary of the invention]

FIG. 6 is a block diagram showing the overall configuration of the present invention.

In FIG. 5, 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 (20 in Figure 4 below)
0.210.220.260.250.270.280
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.

In order to rapidly reduce the engine load, for example, the load that is mechanically driven by the engine, such as the air conditioner or alternator, can be stopped (mechanically cut off with an electromagnetic clutch, etc., or the electric load turned off). There is a method of turning 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 directly affect driving safety, such as heat wires and radios, but it is not possible to completely turn off headlights, etc. Therefore, in such a device, it is preferable to perform date control on the power supply to reduce power consumption within a safe range.

[Embodiments of the invention]

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

An outline of the system of the electronic control device of the present invention will be explained based on FIG. 4.

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) Injector 3 installed in each cylinder of the engine
Fuel injection (EGT) control (aGIOUT 110 ) performed by controlling the valve opening start timing and valve opening time of No. 5.

(2) Ignition (IGN) control (IGN OUT 120) that controls the ignition timing and energization time by controlling the energization/cutoff of the primary coil of the #'Ni-no-Yon coil 68 (IGN OUT 120)
.

(ro) Adjust the lift amount of EGR valve 60 to VCM valve 4.
Exhaust recirculation (
EGR) control (EGROUT 130).

(4) Adjust the lift amount of AAC pulp 50 to 70M valve 4
Idle rotation (ISC) control (ISC0UT150), which is performed by controlling the amount of air bypassing the throttle valve 510 by controlling the negative pressure using zero.

The above are the main objects of control, but there are also the following as optional controls or information output. (5) Fuel pump 530 controlled by fuel pump relay 60 (
D; J7 ・, t7 control (J-"/POU'l'
160), (6) Fuel consumption data 1-1
-70 output (FCM OUT 170), (7)
System self-diagnosis and data exchange with checker 2000 or vehicle information provider 2500 (CIIECK)
), (8) Outputting a warning based on the self-diagnosis result to the alarm lamp 80 (ALAILM OUi' 180)
, (9) Display of self-diagnosis results, etc. on the display 1900 (
MONIT). (10) Air conditioner control signal to the air conditioner relay 90 that turns on and off the air conditioner/funer (air conditioner) = Control (AIRCON) by (A/(:OUT 190 )).

In order to perform the above control and output, the following control information is obtained from each part of the engine and vehicle. '(1) Crank angle sensor 200 built into distributor 520
, the law RF signal 201 and 1 rises every 1200 degrees with the rotation angle of the crankshaft (twice the rotation angle of the distributor).
I) O8 signal 2 where rising and falling occur alternately every °
Get 02.

1) By counting the O8 signal 202 for a predetermined period of time, an engine rotational speed signal 206 is obtained.

(2) The intake air amount Qa of the edge/ is detected by the air flow meter 210. Note that the intake air gluQa is inversely proportional to the air flow meter output voltage signal (AFM) 211.

(02) 2 The output voltage of the sensor 220 changes according to the oxygen concentration in the exhaust gas, and the output voltage changes according to the air-fuel ratio (02) 2
21 is obtained.

(4) A voltage signal ("w) 231 representative of the engine temperature is obtained by the water temperature sensor 260.

(5) Onboard batch 1) 240 supplies electricity to each part of the control system (
-1-1' supply. Control unit 1oooheha Main power supply 241 via control unit relay 540 and auxiliary power supply 2 directly connected to batch 'J240
42 is supplied. Main power supply voltage signal (VB) 241
It is also used as information for control purposes. Furthermore, since the battery voltage is applied not only when the ON terminal 262 of the ignition switch 260 is in the ON position, but also in the 'L' position, the control function is not activated during cranking.
A main power source 241 is supplied to the unit 1000.

(6) Vehicle speed is proportional to vehicle speed by 250)+)
A signal (VSP) 251 having a response density is obtained.

(7) Switch 260 u This is the switch that the driver operates to start, operate, etc. the engine.
TAR1” terminal voltage signal (S’J”AI is also T) 261
You can tell whether cranking is in progress or not.

(8) Throttle valve sensor 270 i, l:
, SrJ Outputs a throttle opening (it""1 (TVO) 271 proportional to the opening of the nottle valve.

(9) Air conditioner switch 28DiJ air conditioner/
This is a switch that closes when the Yona is activated, and the terminal voltage signal (A/C) 281 detects whether or not the air tip is activated.

(10) The gear position of the neutral switch 290i, il/lanosminotion is 211 tral or no S
- This is a switch that closes when it is in the king position, and the gear position of the transmissive gear is detected by its opening/closing signal (NEUi'') 291.

Each signal explained above is control -nit 1000
input and output to. 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. It is still connected to the vehicle information providing device 2500 via a data transfer connector 2510. Control Unino) 1000 has a microconheater, determines the control state of each controlled object based on the above control information (input signals), issues control signals (output signals), and optimally controls the engine. At the same time, information related to this control l is output.

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

In Fig. 5, 1100 is a signal shaping circuit that inputs various input signals from the engine and various parts of the vehicle, and removes noise from these various input signals and absorbs surges. In addition to preventing damage due to malfunctions or surges, various input signals are amplified or converted to be arranged in a form that allows the next input interface circuit 1200 to operate correctly. 12
00 is an input interface circuit, which performs analog-to-digital (AD) conversion of various input signals that have been shaped by the signal shaping circuit 11oO, counts the number of pulses during a predetermined time, and sends the signals to the next central processing unit. (CI)U
) 1300 converts it into a digital code signal so that it can be read as input data, and stores it in an internal register as input data. 1300 is a central processing unit (CPU) which generates an oscillation signal 16 of crystal vibration 1'-1310.
11, and operates in synchronization with ``C'', and is connected to each part via bus 1320, and masks It, 0M1410 and gate of memory 1400 are also 0.
Executes the program stored in the M1420, reads various input data from each register in the human interface circuit 1200, performs arithmetic processing to calculate various output data, and outputs it to the register in the output interface circuit 1500 at a predetermined timing. Send data. The memory 1400 is a data storage device, and includes a mask ROM 1410.
, PROM 1420, ILAM 1460, and memory holding memo IJ 1440. and the mask l(,0
The M1410 permanently stores the programs executed by the CPU 1300 and the data used when executing the programs.1) The ROM 1420 is a mask RO that can be changed depending on the car model and engine type.
Programs and data similar to the M1410 can be permanently written and stored before being incorporated into the Control Unino) 1000. The RAM 1430 is a readable and writable memory that stores data during arithmetic processing and result data that are temporarily stored before being sent to the output interface circuit 1500. 260 turns off and main power supply 2
If 41 is IJJ, it will not be held. Also memory retention memo I
J1440 handles result data and intermediate data of arithmetic processing,
The memory is retained even when the ignition switch 260 is turned off and the vehicle is not being driven.

1350 is an arithmetic timer circuit that enhances the functionality of the CPU 1300, and includes a multiplication circuit for speeding up arithmetic processing, an interval timer that sends an interrupt signal to the CI'U 1300 at every predetermined time period, CPU
130[1 has a free run counter, etc., which is used to know the elapsed time from a predetermined event to the next event and the event occurrence time. 1500 is an output interface circuit which receives output data from the CPU 130 (1) into an internal register and converts it into a pulse signal having a predetermined timing and time width or a predetermined period and data ratio. ”, “o” and sends it to the drive circuit 1600.Drive circuit 1600
is a power amplifier circuit, and the output interface circuit 15
In response to the 00 signal, voltage and current are amplified using transistors, etc., to drive various actuators and display.
-1000° via a connector 2010 to send an output signal to a checker 2000 that diagnoses the control system and displays the results.

1700 is a backup circuit, and a drive circuit 1600
Cl) U160D
, when the memory 1400 or the like fails and does not operate normally, it receives part of the signal from the signal shaping circuit 1100 and issues the minimum necessary control output to enable the engine to rotate and drive the vehicle, A switching signal 1701 is issued to notify the occurrence of a failure.

1750 is a switching circuit, and a backup circuit 1700
The signal from the output interface circuit 1500 is cut off by the IJJ exchange signal 1701 from the IJJ exchange signal 1701, and the signal from the backup circuit 17[]0 is passed.

Reference numeral 1800 denotes an electric loss circuit, which supplies stabilized power supply voltages 1810.1820.1860.1880.1890 to various parts, and controls the operation of CPU1'500.
ESI℃T signal 1840, IT ALT signal 18
50, outputs a battery voltage signal 1830, etc.

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.
Although it is realized by the hardware shown in the figure and the program executed by the cPu 1300, it is shown in the form of a block diagram to make the image easier to understand.

The overall configuration and general operation will be explained below.

First, the actual operation pattern sub-means 6100 inputs various input signals 203, 211, 271, etc., samples them for a predetermined period at predetermined intervals, and sequentially stores them. The actual operation pattern data 3101 is stored in the form of pattern data as to what kind of operation pattern there is in terms of speed, etc.

On the other hand, various input signals 281, 291, etc. are also input to the operation change pattern creation means 6200, and operation pattern data predicted as changes in engine rotational speed, intake air 111, etc. are generated according to the movement of the Buddha. Select and output as motion change pattern data 6201.

The predicted operation pattern synthesis means 3300 inputs actual operation turn data 3101 and operation change turn data 201, synthesizes and processes both, and calculates future rotation, intake air amount, throttle, etc. Predicted action 2-turn data 66 that predicts what will happen in the ζ-turn of the action.
Create 01. If the motion change amount, C-turn, is zero, the predicted motion (turn data 3601 is the same as the actual motion pattern data 6101).

The actual state determining means 400 receives various input signals 203.21.
1.261.271.281.291, etc., the engine state, for example, an unsteady state such as engine stall, acceleration, deceleration, gear change, etc., is determined, and actual state data 6401 is output.

The state-specific operation pattern storage means 6500 distinguishes each engine state according to the actual state data 6401, and stores actual operation patterns such as rotation, intake air amount, and throttle opening when the engine state occurs. Data 3101 is stored as state-specific operation pattern data 3501.

In addition to the actual operation pattern data 6101 that is generated and stored during engine use, the state-specific operation <turn data 6501 includes data stored in advance at the time of manufacturing the control 1 device, as described in side 1. The five-engine state estimation means 6600 includes the predicted operation pattern data 36.
01 and state-specific operation pattern data 3501, and if they match or approximately match, it is estimated that the engine state corresponds to the matched state-specific operation pattern data. and outputs engine state estimation data 3601.

The control output calculation means 3700 calculates E based on various input signals.
Control output (11
0, 120, 130, 150, 190, etc.) is 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 putter 7 when the engine rotates 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 decreases, so the edge/rotational 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) may not be appropriate, the clutch may be disengaged too late and the rotational speed may drop sharply, or the ignition timing may be incorrect. If the throttle is
(If the air-fuel mixture is not stably supplied due to dirt in the vicinity of the lubricant, the engine will not stably reach an idle state) and a notching phenomenon will occur, causing the rotational speed to gradually decrease. (section B), the engine may eventually stall (section C).

Here, for example, measure the rotation movement pattern in section 1) and judge whether the pattern is as shown in the figure (
pattern recognition) and determines that the pattern is likely to cause the engine to stall, that is, if it is estimated that the engine will stall, the engine load is reduced (for example, the air conditioner is turned off) at the end of section D to reduce the engine load. By increasing the surplus torque, it is possible to prevent the engine from stalling.

FIG. 8 shows a CPU as an actual operation pattern measuring means 100.
13 is a flowchart of a program 3150 executed by the program 1300.

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 an open section.

The open side section is, for example, one section 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.

If it is within the open side section, the measured data is sequentially sampled in step 3152 and stored in AM 1430. As a result, the actual engine rotation pattern is displayed as actual operation pattern data 6101. The operation of the operation change pattern creating means 6200 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,
For example, when the air conditioner switch is turned on,
This is detected, and the rotational speed is predicted to change as shown in section A starting from that time.

FIG. 10 is a flowchart of a program 6250 for calculating motion change pattern data 3201. The microconbeater contains pattern data in advance of the change in rotational speed when the air conditioner is turned on (the value starting from the starting point of section A in Figure 9 as zero) and the change in rotational speed when the air conditioner is turned off (value starting from zero). The starting point of section 13 in Figure 9 is set to zero)
pattern data are stored. The program started by the scheduled interrupt determines whether or not the air conditioner is turned on at 3251 from the air conditioner switch data, and if YES, at 6252 the program changes the pre-stored change when the air conditioner is turned on. The pattern data for the minute is selected and output as the pattern data for the motion change 3201. Similarly, when off, 6256 and 6254 select and output data when off.

Next, the operation of the predicted operation pattern synthesis means 6600 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 1 during deceleration, if the air conditioner is turned on at time ①, the rotational speed changes as shown in 1). In this case, the rotational speed is high enough so that there is no need to worry about the engine stalling. On the other hand, if the air conditioner is turned on at time ■, the rotation speed will change as shown in C, and the rotational speed will drop significantly and there is a strong possibility that the engine will stall.Figure 12 shows the rotation as explained above. 33 is a flowchart of a program 3350 that creates predicted motion pattern data 3301 for predicting the motion pattern data 3301.

First, step 3651 is executed, for example, at time points ■ and ■ in FIG. 11, and the subsequent rotational change pattern is calculated by extrapolating from the actual operation pattern data 3101 at that time point. That is, the extension of line a is estimated.

6352 is the operation change pattern data, '5201
is added to the extrapolated data. As a result, predicted motion pattern data 6601 such as b and C is created.

In addition, if the change is gradual, it is sufficient to simply connect the operation change pattern data 6201 to the rotational speed at times ① and ② without interpolation. In addition, if there is no operation such as turning on or off the air conditioner, the operation change pattern data 6201
Since is zero, the predicted motion pattern data 6601 becomes the actual motion pattern data 3101 itself. This applies to cases such as deceleration hunting shown in FIG.

Next, FIG. 15 is a flowchart of the program 450 that creates the actual state data 6401.

First, check the engine rotation speed with 6451, and then
If the rpm is below, the data 5401 is changed to data representing engine stall at 3452. otherwise 345
In step 6, data 3401 is set to data indicating that the engine is rotating. 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 movements of the throttle, intake air amount, etc.

Next, Figure 14 shows operation pattern data 350.1 by state.
This is a flowchart 1 of a program 3550 for creating ゜.

First, the actual state data 6401 is checked in 3551, and if the engine stalls, the pattern in the immediately preceding actual operation pattern data 3101 (section 1 in Fig. 7) is checked in 6552.
data) is stored as operation pattern data when the engine stalls. This data is stored in the storage memory 1440 (see FIG. 5), and the ignition switch 26
0 is turned off and the main power is turned off, the memory is retained. As a result, the operating pattern of the engine rotation when the engine stall actually occurs while the engine is in use is stored.

Incidentally, in addition to the above-mentioned data, an operation pattern when the engine stalls that occurs in a development experiment or the like is stored in advance as another driving pattern data 65o1 when the engine stalls. Specifically, when manufacturing the control device, the mask ROM 1410,
Store it in FROM 1420 or the like. It is also possible to store operation pattern data according to engine conditions such as acceleration and deceleration by adding similar programs.

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

Figure 15 shows predicted movement pattern data 6 at the time of engine stall.
FIG. 5 is a diagram showing the relationship between RO 01 and state-specific operation pattern data RO 501.

In FIG. 15, line a is data stored in the state-specific operation pattern storage means 65oO, and is operation pattern data 65o1 when the air conditioner is turned on during deceleration and the engine stalls. In reality, section B in the diagram is stored, but for the sake of clarity, the engine rotation in sections A and C before and after it is also shown.

Line b is predicted operation pattern data 630f created by the above-mentioned predicted operation pattern synthesis means 6300 when the air conditioner is turned off at time point (2). Similar to the state-specific operation pattern data 65D1, the state of rotation before and after is also illustrated.

The engine state estimating means 6600 calculates the area of the notch/g part (the part surrounded by lines a and b of section B) in the figure,
Depending on whether the size is larger or smaller than a predetermined value, it is determined whether or not the engine will stall if left as it is.
If the value is smaller than a predetermined value, the engine condition is predicted to reach stalling.

Next, FIG. 16 shows a program 66 by which the engine state estimation means 600 calculates engine state estimation data 6601.
50 is a flowchart.

First, in 3651, predicted motion pattern data 01 and state-specific motion pattern data 35 stored in plural numbers are stored.
The difference (3
301-3501-1) are sequentially calculated and integrated over the entire section I3. As a result, line b in FIG.
The difference area data between and a is calculated using the sign. This difference area data is compared with a predetermined value at 6652. If it is thicker 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 possibility of engine stalling, so it is determined that engine stalling will occur, and in step 656,
The engine state estimation data 6601 is made into data representing engine stalling.

6654.3655 and below, similar processing is performed on the second and sixth (for example, pattern data at the time of engine stall due to deceleration hunting in FIG. 7) engine state-specific operation pattern data.

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

In this example, since only engine stalling is determined, the difference is determined by the code, and the determination is made only as to whether the engine is stalled or not. However, if engine states other than engine stalling, such as acceleration and deceleration, are to be identified, the difference may be used. By integrating the absolute values of , calculating the area itself, comparing the results, and setting the engine condition estimation data to different values according to the results, it is possible to determine which of the multiple operating patterns matches or approximately matches. Can be identified. 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 the program 6750 executed as the control output calculating means 6700.

This program is rotationally synchronous, that is, the crank angle sensor 20
This is a program that is started by an interrupt signal generated by a signal every 120 degrees of crank angle from 0 (It upper +-゛ signal 201).

t f 3751, engine state estimation data 3601
Check whether the engine is stalled or not. If it is determined that the engine will not stall, 67
At 52, normal control is performed. The details of the normal control are well known from the aforementioned S and I papers 800056 and 800825, and will therefore 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 method of turning off the air conditioner to lighten the load on the engine to generate excess 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 way to indirectly reduce load torque, turn off electrical loads such as heaters (fan motors), rear window hot wires, radios, stereos, and other devices that can be turned off without causing any problems in an emergency.

Specifically, a relay is installed in the power circuit to control it. Incidentally, it is sufficient to include one relay in common in these power supply systems.

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

These reduce the power supply current by intermittent power supply and data 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.

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

The method of increasing the generated torque as described above has a slower response than the method of reducing the load described above, so there is a risk that it will not be enough to avoid the engine stall if it is used alone, but if the two are used together, the engine stall will be more reliably prevented. It can be 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 diagram corresponding to the control system of the device in FIG. 1, FIG. 6 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 diagram of the device, Figure 5 is a circuit configuration diagram of Control Unino) 1000, Figure 6 is a block diagram showing an embodiment of the control system to which the present invention is applied, and Figure 7 is the engine rotation before and after engine stall. Figure 8 is a flowchart of a program executed by the CPU as an actual operation pattern measuring means, Figure 9 is a diagram showing changes in engine speed when the air conditioner is turned on and off, and Figure 10 is a diagram showing changes in operation. Flowchart 1 of the program that calculates minute pattern data 6201. FIG. 11 is a diagram showing changes in engine speed when the air conditioner is turned on during deceleration, and FIG. 12 shows predicted operation pattern data 3301. FIG. 13 is a flowchart of the program to create the actual state data 6401, FIG. 14 is a flowchart of the program to create the state-specific operation pattern DCR 501, and FIG. 15 is the predicted operation pattern when the engine stalls. A diagram showing the relationship between data 6601 and state-specific operation pattern data 6501, FIG. 16 is a flowchart of a program 650 that calculates engine/state estimation data 6601, and FIG. 17 is executed as control output calculation means 3700. It is a flowchart of the program. Explanation of symbols 20...Sensor group 21...Prediction means 22...Control means Agent patent attorney Junnosuke Nakatoshi Volume 7 Umbrella 8m Age 10 Figure Henna 11 Figure +131 from Figure 10! From figure 13 to l 5t'14 Flash 1F figure 15 elapsed time? 16 figures 1000 (4 figures good)

Claims (4)

[Claims] (1) Safety device that detects the operating status of the engine and auxiliary equipment
-IJ-t, a first means for predicting the occurrence of an engine stall from the output of the sensor; and a second means for reducing the load on the engine when the first means predicts the occurrence of an engine stall. It is equipped with a one-task recording device. (2) A patent claim characterized in that the second means reduces the engine load by stopping or reducing loads mechanically driven by the engine, such as near conditioners and alternators. The title device according to item 1. (3) The above second means includes lights, heaters, hot wires,
Stopping or reducing the electrical load of radios, etc.
2. The device according to claim 1, wherein the device reduces engine load. (4) The device according to claim 6, wherein the second means stops or reduces the electric load by duty-controlling the electric power supplied to the electric load. .