JPS60128028A - Antiskidding control method for power train - Google Patents

Abstract

PURPOSE:To keep off any slip in a car without fail, by detecting the car slip due to a difference in revolutions between left and right driving wheels and, in response to this detection, controlling a power train so as to cause driving torque to be decreased to some extent. CONSTITUTION:A power train control unit is provided with one control unit 1000 in common with both of an engine 3 and a transmission 4. The control unit 1000 inputs each of signals with regard to each crank angle, crankshaft torque, suction air flow and temperature of an ignition switch 10, an accelerator pedal 11, a brake pedal 12, a parking brake lever 13, a select lever 14 and the engine 3. In addition, signals with regard to each speed of revolutions in right and left driving wheels 2L and 2R are inputted by each of electric circuits 31 and 32, and the calculated results of these input signals are outputted to the engine 3 and the transmission 4 by wire harnesses 23 and 24, thus control takes place.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for controlling a power train so that a vehicle does not slip when starting or accelerating on a particularly slippery road surface.

Conventionally, as a powertrain control system for the purpose of preventing vehicle slippage, as shown in Japanese Patent Application Laid-Open No. 58-38347, the average rotational speed between the front two wheels and the average rotational speed between the rear two wheels are conventionally used. There is a known type that detects vehicle slip based on the difference in speed, and when slip is detected, reduces the output torque of the engine, which is the power source of the power train, to prevent slip.

However, this method has the following problems because slip is detected from the difference in average rotational speed between the two front wheels and the two rear wheels.

In other words, when starting or accelerating on a slippery road surface such as a snowy road or muddy road, excessive torque is transmitted to the left and right drive wheels, and the frictional force between the two drive wheels and the road surface is different. Since the power is distributed and transmitted to the left and right drive wheels via the differential gear, a difference in rotational speed occurs between these drive wheels, causing the vehicle to slip, which is called sideslip. By the way, with the conventional method of detecting slip from the average rotation speed difference between the front two wheels and the rear two wheels, even if the above phenomenon occurs, due to the presence of the differential gear, the rotation speed of the left and right drive wheels is extremely high compared to the input rotation to the differential gear. The left and right drive wheels (front two
Since the average rotational speed of the wheels (or the two rear wheels) does not change, sideslip caused by the above phenomenon cannot be detected, and the power train cannot be controlled to prevent it. or,
A total of four wheel rotational speed sensors, one for each wheel, are essential, and the disadvantage is that the device becomes bulky.

The present invention detects slip based on the difference in rotation speed between the left and right drive wheels based on the fact that vehicle slip is mainly caused by the difference in rotation speed between the left and right drive wheels, and adjusts the power train accordingly. From the viewpoint that if the power train is controlled to reduce the drive torque output from the vehicle, it will be possible to reliably prevent the vehicle from slipping without causing the various types of turning described above. It is an object of the present invention to provide a control method for preventing slipping.

Hereinafter, the present invention will be described in detail based on the embodiments shown in the drawings.

FIG. 1 shows an example of a control device for carrying out the method of the present invention, together with the power train of an automobile to be controlled by the control device. 3 is the engine, 4 is the transmission (
5 is a propeller shaft, 7 is a differential gear, and 8L and 8R are left and right rear wheel axles, respectively. Front wheel 1L.

1R is a steering wheel that is steered by the steering wheel 9 and steers the car, and rear wheels 2L and 2R are the wheels that are steered by the engine 3.
The power is transmitted through transmission 4, propeller shaft 5,
These are drive wheels that are driven by transmission through the differential gear 7 and axles 8m and 8R, and drive the vehicle.

The engine 3 is started by the ignition switch 10.
The vehicle is operated and stopped, and the output can be increased by depressing the accelerator pedal 11 during operation.

As mentioned above, the output of the engine 3 is transmitted to the wheels 2L and 2R to enable the vehicle to run, but this can be achieved by depressing the brake pedal 12 when stopping, and by operating the parking brake lever 13 when parking. This can be achieved by

The transmission 4, which together with the engine 3 constitutes the 3-powertrain that is the object of control in the method of the present invention, is controlled by the operation position of the select lever 14, that is, the parking (P) range;
Rear 1 (R) range, neutral <N) range, forward automatic shifting (
D) The power transmission path is selected according to the range, 2nd speed engine brake (U) range, or 1st speed engine brake (I) range, R, D.

In the U and I travel ranges, the power of the engine 3 is shifted according to the selected gear position and output to the propeller shaft 5.

The power train control device used to carry out the method of the present invention includes one control unit 1000 common to the engine 3 and the transmission 4, and this control unit is constantly supplied with power from the vehicle battery 15 directly through the electric line 16. A power relay 17 that is supplied as power and is connected when the ignition switch 10 is turned on.
It operates by being supplied with power from the vehicle's on-board battery as the main power source through the .

As will be described in detail later, the control unit 1000 receives the signal from the ignition switch 10 through the electric line 18, the signal from the accelerator pedal 11 through the electric line 19, and the signal from the brake pedal 12 through the electric line 20. A signal from the lever 13 is transmitted through the electric line 21, a signal from the select lever 14 is transmitted through the electric line 22, a signal regarding the crank angle, crankshaft torque, intake air flow rate, and temperature of the engine 3 is transmitted through the wire harness 23, and the output shaft rotation of the transmission 4 is transmitted. In addition to inputting signals regarding speed and output shaft torque from the wire harness 24, left and right drive wheels 21.
Signals related to the rotational speed of 2H are input from the electric lines 31 and 32, and the calculation results of these input signals are sent to the wire harness 23.
, 24 to the engine 3 and transmission 4, respectively, to control them. Also control unit 1
000 is supplied with data input signals from the data input device 25 operated by the driver through the electric line 26, changes the operation mode according to these data input signals, and further outputs various data to the display device 28 through the electric line 27. Display various data.

These input/output signals to the control unit 1000 will be explained in detail with reference to FIG. 2. First, to explain the input signals, the ignition switch signal 101 is input from the electrical circuit 18 as a signal corresponding to the operating positions of the ignition switch 10, that is, the lock position, the off position, the accessory position, the on position, and the starter position. Since the operation contents are well known, the explanation will be omitted. The select signal 102 corresponds to each operation range P of the select lever 14.
,R,N.

The accelerator signal 103 is a voltage signal proportional to the amount of depression of the accelerator pedal 11, obtained by a potentiometer, and is input via the electric line 19. The brake signal 104 is a voltage signal proportional to the amount of depression of the brake pedal 12 and is obtained from a potentiometer or the like and is input through the electric line 20. The parking brake signal 105 is also a voltage signal from a potentiometer or the like that responds to the parking brake lever 13. A voltage signal proportional to the operating position is input via the electric line 21.

Note that the brake signal 104 and the parking brake signal 105 can also be obtained by a pressure sensor that responds to the pressing force (braking force) of the brake element instead of the brake signal 104 and parking brake signal 105. Further, although the signals 103 to 105 are analog signals in the above example, they can be directly obtained as digital code signals using an encoder or the like.

The data input signal 106 is a signal from the keyboard or switches of the data input device 25, and is input from the electric line 26.
This data input signal causes the control unit 100 to
0 operating modes, such as control operation and diagnostic testing modes;
Specify a mode emphasizing power performance, a mode emphasizing fuel efficiency, etc. In addition, as the data input signal 106, for example, JP-A-58-
There is one such as that described in Publication No. 13140. The main power source 107 is inputted from the vehicle battery 15 via the power relay 17, and the constantly energized power source 108 is constantly inputted from the battery 15 through the electric line 16.

The crank angle signal 120 is a pulse signal that is generated at every fixed rotation angle of the engine crankshaft, and is input from the wire harness 23. can be obtained by photoelectric detection of the light passing through the rotating core slit. The crankshaft torque signal 121 is a torque-proportional voltage signal obtained by electrically detecting the torque applied to the crankshaft using the magnetostrictive effect, and is input from the wire harness 23. This signal is described in, for example, Japanese Patent Publication No. 35-12447. It can be obtained by silica as described above. The air flow signal 122 is a signal that is inversely proportional to the intake air of the engine 3, and is input from the wire harness 23, and can be obtained by an air flow meter commonly used in fuel injection engines. The engine temperature signal 123 is a signal proportional to the coolant temperature of the engine 3, and is input from the wire harness 23, and can be obtained by a thermistor sensitive to the coolant temperature.

The above various input signals other than the crankshaft torque signal 121 are disclosed in Japanese Unexamined Patent Application Publication No. 1986-57 filed by the present applicant.
As already described in Japanese Patent No. 185501, it can be easily obtained.

The output shaft rotational speed signal 140 is a signal proportional to the output shaft rotational speed of the transmission 4, and is inputted from the wire harness 24, and this signal is a pulse signal obtained by the same means as when the flank angle 8 signal 120 is obtained. It can be obtained by calculating the period or frequency. The output shaft 1-torque signal 141 is a voltage signal proportional to the output shaft torque of the transmission 4 and is input from the wire harness 24, and can be generated by a torque sensor similar to the one used to obtain the crankshaft torque signal 121. The left rear wheel rotational speed signal 142 is a signal proportional to the rotational speed of the left rear wheel (left drive wheel) 2L, and is generated by the same means used to obtain the crank angle signal 120, for example, the sensor 2.
This can be determined by calculating the period or frequency of the pulse signal obtained by 9 and input from the electric line 31. The right rear wheel rotational speed signal 143 is a signal proportional to the rotational speed of the right rear wheel (right drive wheel) 2R, and is a signal proportional to the rotational speed of the right rear wheel (right drive wheel) 2R.
This can be determined by calculating the period or frequency of the pulse signal input from the electric line 32 from 0. In addition, since the average rotational speed of both driving wheels 2m and 2R corresponds to the output rotational speed of the transmission 4, the signal 14G is the same as the signal 142, 1
It is also possible to take the average value of 43.

Next, to explain the output signals, the power relay control signal 201
is for on/off control of the power supply relay 11, and when the engine 3 is running with the ignition switch 10 on or in the starter position, the power supply relay 17 is turned on, and through this, the main power supply 107 is supplied from the battery 15 to the control unit 1000. At the same time, even when the ignition switch 10 is turned off, the power relay 17 is kept on until evacuation for saving data is completed, and main power 101 is continued to be supplied to the control unit 1000. The data output signal 202 is transmitted from the electric line 27 to the display device 2.
8, and causes the display device to display the gear shift position of the transmission 4, the selected range of the select lever 14, or the diagnosis result of the power train control device.

The data output signal 202, like the data input signal 106, is the one described in Japanese Patent Application Laid-Open No. 13140/1983.

The air amount control signal 220 is a throttle opening command corresponding to the accelerator signal 103, and is supplied from the wire harness 23 to a well-known throttle actuator (see, for example, Japanese Patent Publication No. 58-25853) provided in the engine 3, and is and adjust the engine throttle opening by pressing the accelerator pedal 1.
Set the value corresponding to 1 depression m (accelerator signal 103),
The intake air amount of the engine 3 is made to correspond to the signal 220. Further, during idle link operation of the engine 3, the air amount control signal 220 controls the throttle opening via a throttle actuator so as to keep the idling rotation speed constant as described in Japanese Patent Laid-Open No. 55-160137.
Further, when constant speed driving is instructed by the data input signal 106, the air amount control signal 220 controls the throttle opening degree via the throttle actuator based on a comparison between the vehicle speed based on the output shaft rotational speed 140 and the instructed vehicle speed (feedback control).
to enable constant speed driving. Fuel injection amount control signal @221
is a pulse signal that controls the opening time of the fuel injection valve provided in the engine 3, and is output from the wire harness 23,
Basically, as described in Japanese Patent Application Laid-Open No. 55-125334, from the crank angle signal 120 and the air flow rate signal 122, the above-mentioned valve opening time width -]]- (fuel injection m) which is proportional to the intake air amount is for the sieve. At the same time, various corrections are made thereto, and the results are output as a fuel injection control signal 221 in synchronization with the operation of the engine 3. The ignition control signal 222 is disclosed in JP-A-57-185501@publication and JP-A-5
As described in Japanese Patent Publication No. 4-58116, this signal controls the energization time and energization stop time for the primary coil of the ignition coil provided in the engine 3 in synchronization with the crank angle signal 120, and controls the ignition energy and ignition timing. , is output from the wire harness 23. Note that the ignition energy depends on the engine rotation speed (crank angle signal 12
The ignition timing is controlled to remain constant even if the voltage of the battery 15 changes (calculated from the cycle or frequency of It is determined. E G R
The fill Wl signal 223 is a signal related to the opening degree (exhaust recirculation amount) of the exhaust recirculation control valve 5 provided in the engine 3, as described in Japanese Patent Application Laid-open No. 55-32918, and is output from the wire harness 23, The opening degree (exhaust gas recirculation port) is determined according to the engine rotational speed=12= and crankshaft torque, taking into consideration exhaust gas, fuel consumption, etc.

The gear ratio control signal 240 corresponds to the gear ratio (gear position) of the transmission 4, and
It is output from This gear ratio is the input torque of the transmission 4 (crankshaft torque of the engine 3), that is, the signal 121 or the corresponding signal (accelerator signal 103).
, intake air amount signal 122, etc.) and vehicle speed (output shaft rotational speed signal 14o), and is determined in consideration of drive torque, fuel consumption, vibration, etc. The gear ratio control signal 240 is responded to by selectively driving various speed change solenoids of the transmission 4 as described in Japanese Patent Laid-Open No. 57-47056, Japanese Patent Laid-Open No. 56-24255, and Japanese Patent Laid-Open No. 56-24256. A desired gear position can be obtained by operating the friction element. The lock-up control signal 241 is a signal that controls coupling and release between the input and output elements of the torque converter provided in the transmission 4, and is output from the wire harness 24. The lock-up control signal 241 is disclosed in Japanese Unexamined Patent Publication No. 56-24255, Japanese Unexamined Patent Publication No. 56-2425.
6 and JP-A-57-33253, the crankshaft torque (signal 121) and vehicle speed (signal 14)
0) in consideration of fuel consumption and vibration, and the relative rotation (slip) between the input and output elements of the torque converter is limited as necessary by the above connection and release control.

Next, a specific example of the configuration of the control unit 1000 will be explained with reference to FIG.

In the figure, 1100 is a signal shaping circuit, which handles the various input signals described above.
101-107. 120-123. 140. 14
1, and removes noise and absorbs surges from these input signals to prevent malfunctions of the control unit due to noise and destruction of the control unit due to surges, as well as amplify and convert various input signals. By doing so, the next stage input interface circuit 12
Adjust the waveform so that 00 can operate accurately. The human power interface circuit 1200 performs analog-to-digital (A/D) conversion of various input signals shaped by the circuit 1100, counts the number of pulses during a predetermined time, and performs input processing by the central processing unit (Cp IJ) 1300. It is assumed that the signals can be converted into digital code signals that can be read as data and stored in internal corresponding registers as input data. CPU 1300 is crystal oscillator 13
It operates in synchronization with a clock signal based on the oscillation signal 1311 of No. 10, and is connected to an input interface circuit 12O0, a memory 1400, an output interface circuit 1500, and an arithmetic timer circuit 1350 via a bus 132O.

The CPU 1300 uses the mask R of the memory 1400 during operation.
While executing the control program stored in OM141O and P R0M 1420, various input data are read from each register in input interface circuit 1200, these are processed to calculate various output data, and these output data are output. It is sent to the corresponding register in the interface circuit 1500 at a predetermined timing. Memory 1400 includes the above mask R0M 1410 and PROM
In addition to RAM 1420, this storage device includes RAM 1430 and storage memory 1440. Mask ROM1
410 permanently stores the control program executed by Q p IJ 1300 and the data used when executing the program 15- at the time of manufacture. The PROM 1420 permanently writes and stores control programs and data that are likely to change depending on the vehicle type and the types of the engine 3 and transmission 4 when installed in the control unit. The RAM 1430 is a readable and writable random access memory that temporarily stores data in the middle of arithmetic processing performed by the CPU 1300.
The p U 130G is used to temporarily store data as a result of arithmetic processing before sending it to the output interface circuit 1500, and this stored content is stored when the ignition switch 10 is turned off and the main power supply 107 is turned off as described above. It disappears as soon as it is no longer supplied. Furthermore, the storage memory 1440 is used to store data that should be retained even when the car is stopped, among the intermediate data and result data of the fraud processing performed by the CPU 1300, and is used to store data that should be retained even when the vehicle is stopped driving. Even if the main @9107 is no longer supplied, the above data will continue to be stored and held by the constantly energized power supply 108.

The arithmetic timer circuit 135O enhances the function of the CP U 1300, and is a multiplication circuit for speeding up the arithmetic processing of the CP Ll 1300.
An interval timer that sends an interrupt signal to J1300,
The CPU 1300 includes a 7-rerun counter and the like for knowing the elapsed time from a predetermined event to the next event and the event occurrence time. The output interface circuit 1500 is CPLl
The output data from 1300 is stored in an internal corresponding register, and this data is converted into a pulse signal with a predetermined timing and time width, or a predetermined period and duty ratio,
It is converted into rlJ and rOJ switching signals and sent to the drive circuit 1600. The drive circuit 160O is a power amplifier circuit, which amplifies the voltage and current of the signals from the output interface circuit 1500 and outputs the various output signals 201, 202, 2.
20 to 223, 240, 241.

In addition, 1700 is a backup circuit, and this circuit 170
O is activated by a monitor signal 1110 obtained by monitoring each signal of the drive circuit 160O, and c p U 130
0. When the memory 1400 or the like ceases to operate normally due to a failure, it is possible to receive part of the signal from the signal shaping circuit 1100 and operate the engine 3 and transmission 4 to the minimum extent necessary for safe self-driving of the automobile. It generates an output signal 172O as well as a switching signal 1130 indicating the occurrence of a failure. Signals 112O and 173O are switching circuit 115O
The switching circuit blocks the signal from the output interface circuit 1500 via the signal 1730 and instead supplies the signal 1720 to the drive circuit 1600, allowing the vehicle to drive safely to the repair shop.

A power supply circuit 1800 is supplied with the main type #Q107 and a constantly energized power supply 108. The power supply circuit 180O is the main power supply 10
1 to input interface circuit 1200, CPU U1
300, memory 1400, output interface circuit 1
500 and arithmetic timer circuit 135O with a constant voltage of 5V 18
10, and a constant voltage of 5V 18 to the backup circuit 1100.
20, a signal 1830 indicating on/off of the ignition switch 1O to the input interface circuit 1200, and a reset signal 1840 and CP (J
A signal 1850 for stopping the operation of the input interface circuit 12O0 is supplied with a constant voltage 1860 for its internal A/D converter, and a constant voltage 1870 is supplied to the signal shaping circuit 1100, drive circuit 1600, and switching circuit 1150, respectively. operate as specified. Also, power supply circuit 18
0O is the memory retention memory 1440 from the constantly energized power supply 108
A constant voltage 1880 of 5V is supplied to the ignition switch 10, and this is operated as specified even when the ignition switch 10 is turned off.

The control program of the control unit having such a configuration and the method of arithmetic processing using the control program will be schematically explained with reference to FIG.

The control program can be broadly divided into an initial setting program 300.
O, background program 4O00, interrupt processing program 5000, and subprogram 3100.
It is composed of a seed program.

Ignition switch 1O is turned on, main power supply 10
7, the power supply circuit 1800 outputs the reset signal 1.
840, and in response, the CPU 1300 issues the fourth
In the figure, the control program starts from reset, and first, the initial setting program 3000 sets initial values for the RAM 1430, input/output interface circuits 1200, 1500, etc. (initialization). Thereafter, the background program 4000 is repeatedly executed, and this program consists of a plurality of programs for each processing item, and these programs are executed sequentially in accordance with their arrangement order. While background program 4O00 is running (initial setting program 30)
00) When an interrupt request signal is input, the program being executed is temporarily interrupted and the program moves to the interrupt processing program 5000 starting from the interrupt in the figure, as shown in (2).

The interrupt processing program 5000 first determines the type of the interrupt request signal, and then executes the interrupt processing program 50 according to the determination result.
Select which one from 00 to execute. After the selected program is executed, the program returns to the background program 4000 that is currently being executed, as in (3), and resumes its execution.

Note that if another interrupt request signal is input while the interrupt processing program 5O00 is being executed, the process returns to the interrupt mode as shown in ■, and the currently executed interrupt processing program and the type of the newly input interrupt request signal are displayed. From a comparison with the corresponding interrupt processing program,
Determine which program should be executed first, and depending on the determination result, execute the program corresponding to the new interrupt request signal and return to the interrupted program as in ■, or proceed as in ■ After completing the execution of the current program, a program corresponding to a new interrupt request signal is started.

Programs that are frequently used in the background program 4000 and interrupt processing program 5000 are set separately as subprograms 310O, and when the above subprograms are needed during the execution of each program,
Jump to subprogram 3100 as shown in (3) and execute the requested subprogram. When the execution of this subprogram is completed, the program returns to the program in the middle of execution, such as (1), (2), and (O), and completes the program. Note that there are cases in which another subprogram is executed during the execution of a subprogram, and there are cases in which the interrupt processing program 500O should be executed in response to an interrupt request signal, but illustrations of these are omitted to avoid obscuring the drawing.

Also, depending on the program, it may be a problem if an interrupt request is received while the program is running, so for such programs, interrupt reception is prohibited (called masking) before the program starts, and interrupts are disabled when the program ends. The ban will be lifted upon reception of

The details of this control program are shown in FIG. 5, and the control program will be explained in detail below based on this drawing.

The initial setting program 300O is a program that starts execution from a specific address called a reset vector address by the reset signal 1840 when the main power supply 107 is turned on by turning on the ignition switch 10. The initial value setting (initialization) of the RAM 1430, input/output interface circuits 1200, 1500, etc. is performed, that is, preparations for subsequent programs are performed. In this program, after clearing all RAM addresses that should be used by the microcomputer,
Commands required for the operations of the input/output interface circuits 1200 and 1500 and the calculation timer circuit 1350 are written, and these operations are started.

These commands include canceling the interrupt mask for interrupt signal processing, setting the timer interrupt cycle, setting measurement times for measuring various rotational speeds and vehicle speeds, and constants related to the output signals of each control. This includes settings such as , initial output state settings, etc.

When such initial settings are completed, an interrupt permission command is issued to the CPU 1300, and the CPU 1300 waits for the start of control.

Background program 4O00 is CPU1300
A program that is always executed during normal operation, that is, unless there is an interrupt request, that generally does not require much urgency due to the control characteristics, or that requires a particularly long calculation time, or that uses steady control constants. These calculations are executed during the CP IJ 1300's free time. The background program 4000 consists of a steady-state control data calculation program 4100, a low-speed correction data calculation program 4200, a learning control program 4300, and a check program 4400. These programs are sequentially executed in a predetermined order, and when the final program is completed, Return to the top program again and repeat this. Thus, the control unit 1O00 outputs the corresponding output signals 201, 202, 220 to 22 during steady operation of the automobile 23-
3,240,241, the engine 3 is controlled by the signals 220 to 223, the transmission 4 is controlled to the operating state suitable for steady operation by the signals 240, 241, and the power relay 17 is kept on by the signal 201. The main power supply 107 is continuously supplied to the control unit 1000, and necessary information can be displayed on the display device 28 by the signal 202.

The interrupt processing program 5000 is a program that is started by interrupting the currently running initial setting program 3000 or background program 400O due to various interrupts, and is started by interrupting the timer interrupt processing program 5100 (5110, 5120, 5130),
Angle coincidence interrupt processing program 5200 (5210)
, A/D conversion processing program 5300 (531G)
, external interrupt processing program 5400 (5410)
, rotation measurement end interrupt processing program 5500 (551
0), an interrupt processing program group consisting of an external pulse interrupt processing program 5600, an overflow interrupt processing program 5700, and a data reception interrupt processing program 5800 (5810); 600
The acceleration control program 6100.0 is executed according to the ranking determined by 0. Deceleration control program 6200,
Starting control program 630O1 Shifting control program 6400. It is composed of a priority processing program group consisting of a lock-up control program 6500, an engine stall prevention control program 6600, a time synchronization control program 6700, an angle synchronization control program 6750, and a data input/output program 6800.

Next, these programs will be explained in order. When there is a timer interrupt, the timer interrupt processing program 5100 is selected, and in this program, the A/D conversion starting program 5120 is executed first. When the input interface circuit 1200 A/D converts a plurality of analog input signals and uses them for control while switching the multiplexer, the program 5120 performs A/D conversion, starts the converter, and switches the multiplexer, and converts the analog input signals into analog signals. This is a program that manages measurements. Next, the clock signal output program 5110 is executed, which is c p U 1
300, memory 1400, output interface circuit 1
This is a program for outputting a clock signal of a constant period to indicate that the 500, etc. are operating normally, and for notifying the outside of their operating status. And finally time period JOB
The start reservation program 513O is executed, and this program controls the time cycle (controlled in synchronization with a fixed time cycle) > JOB processing processing buttogram movement (for details,
JOB execution priority determination program 6
Emit at 000.

When an angle match interrupt (an interrupt issued each time the engine 3 reaches a predetermined crank angle) occurs, the angle match interrupt processing program 5200 is selected.

In this program, the activation of a program (angle amount 111 JOB processing program) that requires processing in synchronization with the rotation of the engine (more specifically, the activation request for the JOB) is performed in the angle synchronized JOB activation reservation program 5210.
Issued to the execution priority determination program 6O00.

When the A/D BLJSSY flag check interrupt occurs, the A/D conversion completion processing program 53O0 is selected.
Here, the Al1 BLJSSY flag is checked to determine whether A/D conversion has been completed. If it has been completed, the A/D conversion value storage/operation status specific JOB start reservation program 531O stores the A/D conversion data in the corresponding RAM according to the A/D conversion channel data.
1430, and determines the driving state of the vehicle from time series data of A/D conversion values related to the accelerator signal 102, for example, as will be explained in detail later, and creates a JOB processing program for each driving state according to the driving state. (more specifically, a request to start the JOB) is issued to the JOB execution priority determination program 6000.

When an external interrupt occurs, the external interrupt processing program 5400
is selected. The external interrupt is an emergency interrupt that is issued to cut off the main power supply 107 to the control unit.
The program 540O selected thereby transfers data that needs to be saved for use in self-diagnosis, learning control, etc. from the ROM 1430 to the storage memory 1440 by executing the power-off data saving program 541O.

27- When the engine rotation 81 measurement end interrupt occurs or the left and right drive wheel rotation speed measurement end interrupt occurs, the rotation measurement end interrupt processing program 550O is selected, and this program is provided in the input interface circuit 1200. Activated by an interrupt request generated every time the measurement of the circuit that measures the frequency of the crank angle signal 120, left rear wheel rotation speed signal 142, and right rear wheel rotation speed signal 143 (counts the number of pulse inputs in one fixed time) is completed. be done. When the measurement of the engine speed (crank angle signal 120) is completed, the engine speed is read by the engine stall determination RPM calculation program 5510, and it is determined whether engine stall occurs or not, and a request to start the engine stall prevention control program 6600 is issued. Issued to the JOB execution priority determination program 6000. When the measurement of the left and right drive wheel rotational speeds is completed, the slip occurrence detection program 552O determines whether or not slip occurs as described later with reference to FIG. The JOB execution priority determination program 600 sends a start request for the program 6300 or, if it is during acceleration, a start request for the acceleration control program 610028-.
Emit at 0.

The external pulse interrupt processing program 5600 is a program that is executed when a key on the keyboard is operated or when a pulse signal is input from an external device, and executes control according to the pulse signal. Further, the overflow interrupt processing program 510O is a program executed by an interrupt issued when the timer overflows, and executes a predetermined process.

The data reception interrupt processing program 5800 is selected by the data reception interrupt and stores the received data in the RAM by the reception data processing JOB start reservation program 581O.
1430, and then process the received data JO.
The JOB execution priority determination program 6000 issues a start-up request for B (more specifically, a start-up request for the JOB).

The JOB execution order determination program 6000 accepts a request to start a corresponding JOB from each of the above-mentioned interrupt processing programs, and sets a predetermined pit (referred to as a flag) at a predetermined location in the RAM 1430 corresponding to the JOB to "1" from rOJ.
”. An execution priority is assigned to each JOB in advance, and the order of addresses and pins I~ is determined according to the priority. In this program, RAM 143
The bits of the address in 0 are checked in order from the highest order, and if there is a reserved program, the reservation is canceled at the same time as the execution of this program starts (setting the flag to rO
(reset to J). When the execution of the program ends, the process returns to the JOB execution priority determination program 6000 again.
The reservation program of the next rank is executed and its reservation is canceled, and when all the reservation programs have been executed, the process returns to the background program 4000.

Next, to explain the priority processing program group whose priority is determined by the program 6000, the acceleration control program 610O is designed to optimize the fuel injection amount, ignition timing, and exhaust gas according to the degree of acceleration during acceleration of the vehicle. Control output data regarding the recirculation amount, intake air amount, gear ratio, necessity of lock-up, etc. is calculated. For example, in the case of sudden acceleration (when the accelerator signal 103 suddenly increases), the engine 3 is controlled so that its output increases rapidly, that is, the amount of fuel injection increases, the ignition timing advances, the amount of exhaust recirculation decreases, and the amount of intake air increases. At the same time, the transmission 4 is controlled so that its output torque increases, that is, the lock-up of the torque converter is released and the gear ratio increases. However, if the vehicle slips during acceleration, the engine 3 is operated so that its output torque decreases, that is, the fuel injection amount decreases, the ignition timing is delayed, the exhaust gas recirculation amount increases, and the intake air amount decreases. and control the transmission 4 so that its output torque decreases.
That is, the gear ratio is controlled to be small.

The engine 3 and the transmission 4 can be controlled depending on the occurrence of slip, only for any selected one, a combination, or all of them.

The deceleration control program 6200 calculates various optimal control output data according to the degree of deceleration, vehicle speed, engine rotation speed, etc. during deceleration of the automobile. During this deceleration 31, for example, the engine 3 is controlled so that the fuel consumption is minimized, that is, the fuel injection amount is zero or very small, and the transmission 4 is controlled so that the gear ratio and the operating state of the torque converter are optimized to achieve the optimal feeling of deceleration. control so that

The start control program 630O calculates various control output data to control the engine 3 and transmission 4 so that sufficient starting torque is obtained when the vehicle starts.
If the vehicle slips when starting, engine 3
control output data 220 so that the output torque of
223 is selectively or completely corrected, and the control output data 240 is corrected so that the output torque of the transmission 4 is reduced. In other words, engine fuel injection 01
Selectively or globally perform data corrections such as reducing ignition timing, retarding ignition timing, increasing exhaust gas recirculation, and reducing intake air volume; Correct the data to make it smaller.

The shift control program 6400 is a control program for the transmission 32.
- Calculate various control output data to control the engine 3 in terms of output torque and rotational speed while controlling the transmission 4 to change gears so as not to cause a large shift shock to the occupants when shifting the engine 4.

The lock-up control program 65O0 calculates various control output data to perform lock-up control of the torque converter and output control of the engine 3 so as to reduce the shock when locking up and releasing the lock-up of the torque converter.

The engine stall prevention control program 66O0 determines the change state of the engine rotation speed in the program 5510, and
This program is executed when an engine stall is predicted to occur, and calculates various control output data to control the engine 3 and transmission 4 to urgently increase engine output and lighten the load to prevent engine stall. .

The time synchronization control program 6700 is a program that is reserved and executed at regular intervals, and updates and changes various data at regular intervals, writes control data to the output interface circuit 1500, and the like.

The angle synchronization control progera l-, 6750 is a program that is reserved and executed at each fixed crankshaft angle of the engine 3, and updates and changes various data at each crankshaft angle, and sends control data to the output interface circuit 1500. Perform writing, etc.

The data input/output program 6800 is a program that is reserved and executed at fixed intervals or when a special electric line has generated a data reception interrupt, and determines and stores the data contents when data reception is input, or changes the control state. and output the data contents when outputting data transmission.

Next, the operation of the above embodiment will be explained, especially when the vehicle slips.

When the left and right drive wheel rotational speed measurement end interrupt is entered, the slip occurrence detection program 5520 is executed, and this program detects the vehicle according to the flowchart in FIG. 6 based on the left and right drive wheel rotational speed data in the input interface circuit 1200. Slip is determined as follows.

That is, first, in step 5521 d3, it is determined whether the drive wheel rotation speed data read from the input interface circuit 1200 is the same rotation speed of the left rear wheel 2L, and if so, in step 5522, the data is transferred to the left rear wheel. Store it in a predetermined location of RAM 1430 as speed data SL,
If not, in step 5523, the right rear wheel lotus degree data SR is read from another driving wheel rotation speed frequency counter of the input interface circuit 120O, and the RAM
The memory covers the specified location of 1430. Next, control is step 5
Proceed to 524, where the data SL.

The ratio SR/SL of SR is calculated, and it is determined whether f is between the reference values R1 and R8,2 which sandwich 1.0.

If the ratio SR/SL is between these reference values, the data SL,
Since SR is almost the same (SR/SL is close to 1, 0), it means that the left and right drive wheels 2L and 2R are not slipping, and in this case, the slip occurrence flag is set at step 5525-, j D- of the method. Reset F8□□p to rOJ. If the ratio SR/SL is not between the above reference values,
Since the data SL and SR are significantly different, the left and right drive wheels 2L
, 2R means that one of the wheels is slipping,
In this case, in step 5526, the slip occurrence flag F8□ip is set to [1]. The flag F8□i set in this way becomes a start request for the start FR1, II control program 6300 or the acceleration control program 6100 when a slip occurs, and this
It is issued to the execution priority determination program 600O and reserved.

At the time of starting, the program 6000 starts executing the starting control program 6300 when it becomes the execution order, and resets the flag Fs□□p to [0].

As described above, the program 6300 uses the control output data 220 to 223 to reduce the output torque of the engine 3.
, reduce intake air ω, reduce fuel injection, delay ignition timing, increase exhaust recirculation amount, and
The control output data 240 is corrected 36- so that the output torque of the transmission 4 is reduced, and the gear ratio is reduced. By reducing the output torque of the engine and transmission in this manner, the slip of the left and right drive wheels is reduced, and the ratio SR/SL falls within the specified value range, thereby preventing slip when the vehicle starts.

Further, during acceleration, when the program 6000 becomes the execution order, it starts executing the acceleration control program 6100 and resets the flag Fslip to "0". As described above, the program 6100 corrects the control output data 220 to 223 so that the output torque of the engine 3 is reduced, reduces the intake air amount, reduces the fuel injection gate, delays the ignition timing, and reduces the exhaust recirculation amount. The control output data 240 is corrected to reduce the gear ratio so that the output torque of the transmission 4 decreases as the torque increases. By reducing the output torque of the engine 3 and the transmission 4 in this way, the slip of the left and right drive wheels is reduced, and the ratio SR/SL falls within the specified value range, making it possible to prevent slip when the vehicle accelerates. .

Note that in the above example, only whether or not to perform slip control (output torque reduction) of the power train is determined based on the presence or absence of slip, but the deviation of the ratio SR/SL from 1.0 + 1-8R It is also possible to reduce the output torque of the engine, transmission, or both of them by P (proportional), ■ (integral), or D (differential) control according to /SLl, that is, according to the magnitude of slip, In this case, control can be more finely and accurately performed. Further, the control for reducing the torque may be performed using each of the above items alone or in combination of selected items.

Thus, as described above, the method of the present invention applies to the left and right drive wheels 2L, 2.
Vehicle slippage is detected based on the difference in the rotational speed of R (1L and 1R in the case of a front wheel drive vehicle), so it is possible to reliably prevent slips that would cause sideways skidding, and wheel rotational speed sensors are installed, one each for the left and right drive wheels. It is only necessary to provide it, and the device can be made simple.

[Brief explanation of the drawing]

Fig. 1 is a diagrammatic plan view showing a power train control device used to implement the method of the present invention together with an automobile power train, and Fig. 2 is an explanatory diagram of input/output signals of a control unit that is the main part of the power train control device. , Fig. 3 is a block diagram of the control unit, Fig. 4 is a diagram showing an outline of the control program by the control unit, Fig. 5 is a detailed diagram of the control program, and Fig. 6 is a diagram showing the outline of the control program by the control unit. The flowchart of the slip occurrence detection program, FIG. 7, is a complaint correspondence diagram. 2L, 2R... Left and right rear wheels (left and right drive wheels) 3... Engine 4... Transmission... Differential gear 10... Ignition switch 11... Accelerator pedal 12... Brake pedal 13...・Parking brake lever 39- 14...Select lever 15...Vehicle battery 1
7...Power relay 25...Data input device 28.
...Display device 29.30...Drive wheel rotation speed sensor 101...Ignition switch signal 102...Select signal
103... Accelerator signal 104... Brake signal 105... Parking brake signal 106... Data input signal 107... Main power supply 108... Constantly energized power supply 120
... Crank angle signal 121 ... Crankshaft torque signal 122 ... Air flow signal 123 ... Engine temperature signal 140 ... Output shaft rotational speed signal 141 ... Output shaft torque signal 142 ... Left Rear wheel rotation speed signal 143...Right rear wheel rotation speed signal 201...Power relay control signal 202...Data output signal 220...Air flow rate signal 40-221...Fuel injection best control signal 222... ...Ignition control signal 223...EG RI
ll m signal 240...speed ratio control signal 241...lockup control signal 1O00...control unit 1100...signal shaping circuit 1200...input interface circuit 1300...
・Central processing unit (CPLI) 1400...Memory 15O0...Output interface circuit 1600...
・Drive circuit 1700...Backup circuit 1800
...Power supply circuit 3000...Initial setting program 4
00G (4100, 4200, 4300, 4400)
...Background program 5O00...Interrupt processing program 5100 (511G, 5120.5130), 52
00 (5210), 5300 (531G), 54
00 (5410), 5500 (5510, 5520)
. 5600, 5700.5800 (5810)...
Interrupt processing program group 6000...JOB execution priority determination program 61
00-6800...Priority-based processing program group patent applicant Nissan Motor Co., Ltd. 43- Figure 6 Japanese Unexamined Patent Publication No. 60-128028 (17) Figure 7 S-Cho AR Dyo Sajima-ku ψη Warehouse - Turning back The structure of Kichipi 11 moxibustion driving wheel rotation speed cliff of degree SL. Sanskrit sword? <1<Firefly<2) Slip guard slip seal, (Fsttp-/) (FsliP-0 Nogume Seizr

Claims (1)

[Claims] 1. When controlling the power train so that the vehicle does not slip, in which the power from the power train is distributed and transmitted to the left and right drive wheels by a differential gear, the rotational speeds of the left and right drive wheels are individually detected, and these rotational speeds are A control method for preventing a slip of a power train, characterized in that the drive torque output from the power train is reduced during different periods of time to prevent a vehicle from slipping.