JPH02290745A - Power train controller - Google Patents

Abstract

PURPOSE:To improve the traveling stability of a vehicle by allowing the speed change operation of an automatic transmission to follow the first speed change characteristic in the execution of the torque reduction operation when a slip is generated, while by carrying out the change to the second speed change characteristic when the steering angle is less than a prescribed value after the completion of the torque reduction operation. CONSTITUTION:When a slip over a prescribed value for a road surface of a driving wheel W of a vehicle is detected by a slip detecting means A, the torque transmitted to the driving wheel W from the power train C of the vehicle is reduced by a torque control means B. In this case, the speed change operation of an automatic transmission which constitutes the power train C is performed according to the first speed change characteristic when the torque reduction operation is carried out, while after the completion of the torque reduction operation, the speed change characteristic is changed from the first to the second by a speed change characteristic changing means D. However, if the steering angle detected by a steering angle detecting means E is over a prescribed value on or after the completion of the torque reduction operation, a characteristic change control means F prohibits the characteristic changing operation.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a power train control system that performs control to reduce the torque transmitted from the power train to the drive wheels when the drive wheels of a vehicle slip with respect to the road surface. Regarding equipment.

(Prior Art) In a vehicle equipped with a power train consisting of an engine and an automatic transmission connected to the engine, when the drive wheels slip on the road surface while driving, the power train transfers power to the drive wheels. It has been proposed to perform traction control that suppresses the slip of the drive wheels on the road surface to ensure driving stability by performing a torque reduction operation that reduces the transmitted torque. In addition, in a power train that performs a torque reduction operation when the drive wheels slip on the road surface, for example, as shown in Japanese Patent Application Laid-Open No. 60-176828, the gear position in the automatic transmission is It is also known to change the gear to a higher gear than the gear immediately before the slip occurs.

When traction control is performed in the powertrain as described above, the shift operation in the automatic transmission is such that the shift line is at a lower vehicle speed than the shift characteristic for normal driving that is adopted when traction control is not performed. The shift is performed according to the traction control shift characteristics corresponding to the shift to the side. After the traction control is completed, the shift operation in the automatic transmission is returned from the traction control shift characteristic to the normal driving shift characteristic.

(Problem to be Solved by the Invention) The power train is equipped with a power train in which a traction control shift characteristic and a normal drive shift characteristic are respectively adopted in a state where traction control is performed and a normal drive state. In such a vehicle, if the shift characteristics for traction control are unconditionally changed to the shift characteristics for normal driving at the end of traction control, an upshift or downshift will occur in the automatic transmission. This may cause wheel spin. Particularly when the vehicle is turning or when the coefficient of friction of the road surface on which the vehicle is running is small, if such wheel spin occurs, even if it is relatively small, for example, traction control An undesirable so-called hunting phenomenon occurs in which the state and the normal running state are repeated within a short period of time, which may adversely affect the running stability of the vehicle.

In view of this, the present invention provides an automatic transmission with Traxigon control that reduces the torque transmitted from the power train to the drive wheels when the drive wheels slip on the road surface, which is different from the shift characteristics for normal driving. In addition, after the traction control is completed, the traction control speed change characteristics are changed to the normal driving speed change characteristics. Provided is a powertrain control device capable of changing from a control shift characteristic to a normal driving shift characteristic under conditions that suppress a situation that adversely affects the running stability of a vehicle. The purpose is to

(Means for Solving the Problem) In order to achieve the above-mentioned object, the power train control device according to the present invention, as shown in the basic configuration in FIGS. a slip detection means for detecting the slip detection means; and a torque control means for performing a torque reduction operation to reduce the torque transmitted from the power train of the vehicle to the driving wheels when the slip detected by the slip detection means is equal to or greater than a predetermined value; The speed change operation in the automatic transmission that constitutes the power train is assumed to follow the first speed change characteristic when the torque reduction operation is performed, and after the torque reduction operation is completed, to change from the first speed change characteristic to a second speed change characteristic different from the first speed change characteristic. A shift characteristic changing means for performing a characteristic changing operation to change the shift characteristic, and a steering angle detecting means for detecting a steering angle of a steering shaft of the vehicle. Lateral acceleration detection means for detecting lateral acceleration acting on the vehicle, road surface friction coefficient detection means for detecting the friction coefficient of the road surface on which the vehicle travels, road surface determination means for determining the condition of the road surface on which the vehicle travels, or vehicle speed detection means. and a characteristic change control means, wherein the characteristic change control means detects the lateral acceleration when the steering angle detected by the steering angle detection means exceeds a predetermined value when the torque reduction operation is completed and thereafter. If the lateral acceleration detected by is above a predetermined value, or if the friction coefficient of the road surface detected by the road friction coefficient detection means is below a predetermined value, blocking the characteristic changing operation by the transmission characteristic changing means; Alternatively, if the road surface is determined to be a bad road by the road surface determination means, or if the vehicle speed detected by the vehicle speed detection means is less than or equal to a relatively small first value, or if a relatively large second value If the value is greater than or equal to the value, the shift state will be brought about until a predetermined period has elapsed from the end of the torque reduction operation, or by changing from the first shift characteristic to the second shift characteristic. In this case, it is configured to prevent the characteristic changing operation by the speed change characteristic changing means.

(Function) In the power train control device according to the present invention configured as described above, when the torque reduction operation is completed, if the steering angle is more than a predetermined value and the lateral acceleration is more than a predetermined value, Alternatively, if the coefficient of friction of the road surface is less than or equal to a predetermined value, changing the shift characteristic in the automatic transmission from the first shift characteristic to the second shift characteristic is performed when the steering angle is less than the predetermined value. It is stopped until the lateral acceleration is less than a predetermined value, or the coefficient of friction of the road surface is greater than a predetermined value, or it is determined that the road surface is rough, or when the vehicle speed is relatively low. If the value is less than 1 or more than a relatively large second value, changing the shift characteristic from the first shift characteristic to the second shift characteristic in the automatic transmission is a torque reduction operation. It is inhibited until a predetermined period of time has elapsed from the time of termination, or when a shift state is to be brought about by changing from the first shift characteristic to the second shift characteristic.

By doing this, the change from the first shift characteristic to the second shift characteristic after the torque reduction operation is completed can be performed without causing wheel spin due to torque fluctuation. be exposed.

(Embodiment) FIG. 2 conceptually shows an example of a power train control device according to the present invention, together with a front engine rear-drive vehicle to which it is applied.

The front part of the vehicle body 5 of the vehicle 1 equipped with left and right front wheels 2 and left and right rear wheels 3 shown in FIG. A power train 10 including an automatic transmission 9 is installed. The engine 8 is assumed to be provided with four cylinders 11, and each of the four cylinders 1L is connected to a fuel supply system through an intake passage 1G provided with a throttle valve l4 that is driven to open and close by a throttle actuator 13. An air-fuel mixture formed by intake air and fuel supplied from the engine is supplied. The air-fuel mixture supplied into each cylinder 11 is combusted by the operation of the ignition system, and the resulting exhaust gas is discharged into the exhaust passage 18. The torque obtained from the power train 10 including the engine 8 which is operated by the combustion of the air-fuel mixture is composed of a propeller shaft 19, a differential gear unit 20, and a pair of drive shafts 1 and 21. The torque is transmitted to the left and right rear wheels 3, which are drive wheels, via a torque transmission system.

In addition to this configuration, there is also a main control unit 30 that performs various operation controls including shift operation control and lock-up operation control in the automatic transmission 9, and an operation control of the throttle actuator 13 during normal running of the vehicle 1. In addition, a sub-control unit 40 is provided that controls the operation of the throttle actuator 13 for traction control.

The main control unit 30 includes a detection output signal Sf representing the driven wheel rotation speed obtained from a first rotation speed sensor 22 provided in relation to the front wheel 2, which is a driven wheel, and a detection output signal Sf representing the driven wheel rotation speed, and a detection output signal Sf representing the driven wheel rotation speed, which is obtained from a first rotation speed sensor 22, which is provided in relation to the front wheel 2, which is a driven wheel. A second rotation speed sensor 23 provided in connection with
A detection output signal Sr representing the driving wheel rotation speed obtained from
, a detection output signal St representing the opening degree of the throttle valve 14 obtained from the throttle opening degree sensor 24 arranged in relation to the throttle valve 14, and a detection output signal St representing the opening degree of the throttle valve 14 obtained from the throttle opening degree sensor 24 arranged in relation to the throttle valve 14; A detection output signal Sa indicating the amount of depression, a detection output signal Ss indicating the steering angle obtained from the steering angle sensor 26 arranged in relation to the steering, and a lateral acceleration (lateral G
) A detection output signal Sg representing the lateral acceleration acting on the vehicle body 5 obtained from the sensor 27 and another detection output signal Sx representing the operating state of the engine 8 are supplied. Based on these various detection output signals, the main control unit 30 sends drive control signals Ca, Cb to the solenoid valves for shift control and the solenoid valves for lock-up control provided in the hydraulic circuit section of the automatic transmission 9. , Cc, Cd and C
e is selectively supplied to open and close the solenoid valve for speed change control and the solenoid valve for lockup control, thereby causing the automatic transmission 9 to perform a speed change operation and a lockup operation.

On the other hand, the sub control unit 40 includes a first rotation speed sensor 2.
Detection output signal Sf representing the rotation speed of the front wheel 2 obtained from the second rotation speed sensor 23, detection output signal Sr representing the rotation speed of the rear wheel 3 obtained from the second rotation speed sensor 23, and throttle valve 14 obtained from the throttle opening sensor 24. and a detection output signal S representing the amount of depression of the accelerator pedal obtained from the accelerator sensor 25.
a is supplied. When the vehicle 1 is normally running without traction control, the sub-control unit 40 sets a normal target throttle opening according to the amount of depression of the accelerator pedal represented by the detection output signal Sa, and detects In order to match the actual throttle opening indicated by the output signal St with the normal target throttle opening, a throttle valve drive signal CTc is generated according to the difference between the normal target throttle opening and the actual throttle opening indicated by the detection output signal St. and supplies it to the throttle actuator l3.

Further, the sub-control unit 40 obtains the driven wheel rotation speed, which is the rotation speed of the front wheels 2 represented by the detection output signal Sf, from the driving wheel rotation speed, which is the rotation speed of the rear wheels 3 represented by the detection output signal Sr. When the rotation speed difference exceeds a predetermined value, it is determined that the rear wheels 3, which are the driving wheels, have slipped on the road surface, and traction control is performed, which is normally smaller than the target throttle opening, according to the rotation speed difference. In order to match the actual throttle opening indicated by the detection output signal St with the target throttle opening for traction control, the target throttle opening for traction control and the actual throttle opening indicated by the detection output signal SL are set. Traction control is performed by forming a throttle valve drive signal CTc according to the difference with the opening degree and supplying it to the throttle actuator 13. When such traction control is performed, the throttle opening degree of the engine 8 is reduced, the output of the engine 8 is reduced, and the torque transmitted from the power train 10 including the engine 8 to the left and right rear wheels 3 is reduced. As a result, the slip of the rear wheels 3 on the road surface is suppressed. Further, when performing traction control by supplying a throttle valve drive signal CTc corresponding to the difference between the target throttle opening for traction control and the actual throttle opening to the throttle actuator 13, the sub-control unit 4o performs traction control. The signal STr is supplied to the main control unit l-30.

When the traction control signal STr is supplied from the sub control unit 40 to the main control unit 22 I-30, the main control unit 30 changes the shift operation characteristics of the automatic transmission 9. That is, when the vehicle 1 is in a normal running state and the traction control signal STr is not being supplied from the sub-control unit 40, the main control unit 30 causes the automatic transmission 9 to transmit information mapped to the built-in memory of the main control unit 30. Drive control signals Ca, Cb, Cc, and Cd are sent to the solenoid valves for speed change control provided in the hydraulic circuit section of the automatic transmission 9 in order to perform a speed change operation in accordance with the normal driving speed change operation characteristics stored in the normal driving mode. is selectively supplied, and under such conditions, traction control is performed, and when the traction control signal STr is supplied from the sub-control unit 40, the automatic transmission 9 is stored in the built-in memory of the main control unit 30. A drive control signal that is selectively supplied to a solenoid valve for speed change control provided in the hydraulic circuit section of the automatic transmission 9 in order to perform a speed change operation according to the mapped and stored speed change operation characteristics for traction control. Ca,C
Change b, Cc and Cd.

The shift operation characteristics for normal driving are, for example, as shown in Figure 3, where the vertical axis represents the throttle opening Th and the horizontal axis represents the vehicle speed. In the shift operation characteristics for normal driving, the shift lines Ua,
Ub and Uc respectively define upshifts from 1st to 2nd gear, 2nd to 3rd gear, and 3rd to 4th gear, and shift lines Ud, Ue, and Uf respectively define upshifts from 2nd to 3rd gear, and 3rd to 4th gear. This specifies downshifts from 1st to 1st, 3rd to 2nd, and 4th to 3rd. In addition, the transmission characteristics for traction control are as follows:
For example, the vertical axis represents the amount of depression α of the accelerator pedal, and the horizontal axis represents the vehicle speed ■, as shown in FIG. , the shift lines Ug and Oh define upshifts from 2nd gear to 3rd gear and from 3rd gear to 4th gear, respectively, and the shift lines U1 and Uj define upshifts from 3rd gear to 3rd gear, respectively.
Shift 1/down from 1st gear to 2nd gear and from 4th gear to 3rd gear. In the shift operation characteristics for traction control shown in FIG. 4, compared to the shift operation characteristics for normal driving as shown in FIG. It has been expanded.

Note that in the shift operation characteristics for traction control, the shift condition is set by the accelerator pedal depression amount α and the vehicle speed V, but even when traction control is performed, the shift condition is set by the throttle opening Th and the vehicle speed ■. If the throttle distance Th is set by The depression amount α of the accelerator pedal is used instead of the opening degree Th. Furthermore, the vehicle speed (2), which sets the shift condition in the shift operation characteristic for traction control, is obtained based on the rotation of the front wheel 2, which is a driven wheel. This is because when traction control is performed, the rear wheels 3, which are the drive wheels, slip against the road surface, and the vehicle speed ■ is determined based on the rotation of the rear wheels 3 where such slip occurs. In this case, the vehicle speed (2) will be accompanied by a pseudo-variation in response to the slip of the rear wheels 3, which may cause the automatic transmission 9 to perform an unnecessary shift operation.

Then, when the traction control by the sub control unit 40 is finished and the traction control signal STr is no longer supplied from the sub control unit 40, the main control unit 30
Thereafter, in order to return the automatic transmission 9 to a state in which the automatic transmission 9 performs a shift operation according to the shift operation characteristic for normal driving instead of the shift operation characteristic for traction control, a shift control The drive control signals Ca, Cb, Cc, and Cd selectively supplied to the solenoid valves are changed again. In such a case, the main control unit 3
0 means that the shift operation characteristic changing operation after traction control is always performed, which switches the automatic transmission 9 from a state in which the automatic transmission 9 performs a shift operation in accordance with the shift operation characteristics for traction control to a state in which it performs a shift operation in accordance with the shift operation characteristics for normal driving. , the traction control is not performed immediately after the completion of the traction control, but is performed in the following manner, for example.

(1) First, when the steering angle indicated by the detection output signal Ss is greater than or equal to a predetermined value at the end of traction control and thereafter, the detection output is Signal Ss
After the steering angle represented by becomes less than a predetermined value, a shift operation characteristic changing operation after traction control is performed.

(2) At the end of traction control and thereafter,
When the lateral acceleration represented by the detection output signal Sg is equal to or higher than a predetermined value, the operation to change the shift operation characteristic after traction control is not performed, and after the lateral acceleration represented by the detection output signal Sg becomes less than the predetermined value, Performs a shift operation characteristic changing operation after traction control.

(3) At the end of Traxidin control and thereafter,
If the coefficient of friction of the road surface on which the vehicle 1 travels is less than a predetermined value, the operation to change the shift operation characteristics after traction control is not performed, and the traction control is performed after the coefficient of friction of the road surface becomes larger than the predetermined value. Perform the subsequent shift operation characteristic changing operation. In this case, the friction coefficient of the road surface changes its value based on the change in the driven wheel rotation speed represented by the detection output signal Sf.
The acceleration is calculated and estimated based on the calculated acceleration and the driven wheel rotation speed.

(4) At the end of traction control and thereafter,
When the vehicle 1 is traveling on a rough road, the transmission characteristics may be changed from the time when the traction control ends until a predetermined period has elapsed, or from the transmission characteristics for traction control to the transmission characteristics for normal driving. In cases where a shift operation in the automatic transmission 9 is caused by this, the shift operation characteristic changing operation after traction control is not performed.

In this case, it is determined whether the road is bad or not when the number of times the acceleration or deceleration of the traveling vehicle 1 exceeds a predetermined value within a predetermined period is a predetermined number or more. done by being done.

(5) At the end of traction control and thereafter,
When the vehicle speed calculated based on the driven wheel rotation speed indicated by the detection output signal Sf is below a relatively small predetermined value or above a relatively large predetermined value, the time when traction control is completed. Until a predetermined period has elapsed from Do not perform a shift operation characteristic change operation after control.

The reason why such a control mode is adopted is as follows. That is, when the shift operation characteristic changing operation after traction control is performed at the end of traction control, an upshift or downshift operation occurs in the automatic transmission 9,
This may cause wheel spin in the rear wheels 3, but if the steering angle indicated by the detection output signal Ss is greater than a predetermined value or the lateral acceleration indicated by the detection output signal Sg is greater than a predetermined value. In some cases, the vehicle 1 is in a turning state, and if the coefficient of friction of the road surface on which the vehicle 1 runs is less than a predetermined value, the vehicle 1 is in a state where it is extremely likely to slip. Therefore, if wheel spin occurs in the rear wheels 3 under such circumstances, even if it is relatively small, for example, the traction control state and the normal driving state may be repeatedly changed in a short period of time. This is because an undesirable hunting phenomenon may occur, which may adversely affect the running stability of the vehicle. Furthermore, when the vehicle 1 is traveling on a rough road, and when the vehicle speed of the vehicle 1 is below a relatively small predetermined value or above a relatively large predetermined value, the traction control is performed. If wheel spin occurs in the rear wheels 3 due to subsequent gear change operation characteristic changing operations, even if the spin is relatively small, the traction control state and normal driving state may change for a short period of time. This is because there is a possibility that an undesirable hunting phenomenon that will occur repeatedly in the future may occur.

The main control unit 30 and the sub-control unit 40 that perform the above-described control are each configured using a microcomputer, but the microcomputer that makes up the main control unit 30 controls the normal running state of the vehicle 1 and the sub-control unit. An example of a program executed to control the operation of the automatic transmission 9 in a state where the control unit 40 performs traction control will be described with reference to the flowcharts shown in FIGS. 5 to 11.

Each of the programs shown in the flowcharts shown in FIGS. 5 to 11 constitutes one step in the main program for performing various control operations repeatedly executed by the microcomputer configuring the main control unit 30. This is executed after various detection output signals are captured in the main program.

When executing the program shown in the flowchart of FIG. 5, the microcomputer constituting the main control unit 30 determines that, after the start, in step 50, the traction control is in progress and the traction control signal STr
Determine whether or not it is being supplied. As a result, if the traction control signal STr is supplied, step 5
At step 1, a control mode is set in which the automatic transmission 9 performs a shift operation according to the shift operation characteristics for traction control (CHTR), and then at step 52, the operation mode flag Fa is set to 1, and the program is ended.

On the other hand, if the result of the determination in step 50 is that the traction control signal STr is not being supplied, then in step 53 it is determined whether the operation mode flag Fa is 1 or not. As a result, if the operation mode flag Fa is 1, in step 54, the steering angle Sθ represented by the detection output signal Ss is the predetermined value θ. Determine whether or not the above is true. Then, the steering angle Sθ is a predetermined value θ. If it is above, the process proceeds to step 51, and the steering angle Sθ is a predetermined value θ.

If it is less than 0, the operation mode flag Fa is set to 0 in step 55, and then in step 56, a control mode is set in which the automatic transmission 9 performs a shift operation according to the shift operation characteristics for normal driving (CHNO), and the program end.

If the result of the determination in step 53 is that the operation mode flag Fa is 0, the process directly proceeds to step 56.

In executing the program shown in the flowchart of FIG. 6, after starting, in step 60, it is determined whether traction control is in progress and the traction control signal STr is being supplied. As a result, if the traction control signal STr is supplied, step 61
In step 62, the automatic transmission 9 is set to a control mode in which the automatic transmission 9 performs a gear change operation according to the traction control shift operation characteristic (CHTR), and then in step 62, the operation mode flag Fb is set to 1, and the program is started. end.

On the other hand, if the result of the determination in step 60 is that the traction control signal STr is not being supplied, then in step 63 it is determined whether the operating mode flag Fb is 1 or not. As a result, if the operation mode flag Fb is 1, it is determined in step 64 whether the lateral acceleration GS represented by the detection output signal Sg is greater than or equal to a predetermined value G0.

If the lateral acceleration Gs is equal to or greater than the predetermined value C0, the process proceeds to step 61, and the lateral acceleration Gs is the predetermined value G. If it is less than the operation mode flag F in step 65,
After setting b to O, in step 66, a control mode is set in which the automatic transmission 9 performs a shift operation according to the shift operation characteristics for normal driving (CHNO), and the program ends.

Further, as a result of the determination in step 63, if the operation mode flag Fb is O, the process directly proceeds to step 66.

In executing the program shown in the flowchart of FIG. 7, after starting, in step 70, it is determined whether traction control is in progress and the traction control signal STr is being supplied. As a result, if the traction control signal STr is supplied, step 71
At step 72, a control mode is set in which the automatic transmission 9 performs a shift operation according to the shift operation characteristics for traction control (CHTR), and at step 72, the operation mode flag Fc is set to 1, and the program is terminated.

On the other hand, if the result of the determination in step 70 is that the traction control signal STr is not being supplied, then in step 73 it is determined whether the operation mode flag Fc is 1 or not. As a result, if the operation mode flag Fc is 1, the friction coefficient μR of the road surface on which the vehicle 1 travels is set to a predetermined value μ in step 74. Determine whether the following is true or not. Then, the coefficient of friction μR of the road surface is a predetermined value μ. If it is below, the process proceeds to step 71, and the friction coefficient μR of the road surface is a predetermined value μ. If it is larger, the operating mode flag Fc is set to O in step 75, and then in step 76, the automatic transmission 9 is set to normal driving shift operating characteristics (CHNO
),
Exit the program.

Further, if the result of the determination in step 73 is that the operation mode flag Fc is 0, the process directly proceeds to step 76.

In executing the program shown in the flowchart of FIG. 8, after the program is started, in step 80, it is determined whether traction control is in progress and the traction control signal STr is being supplied. As a result, if the traction control signal STr is supplied, step 81
In step 82, a control mode is set in which the automatic transmission 9 performs a shift operation according to the shift operation characteristics for traction control (CHTR), and in subsequent step 82, the operation mode flag Fd is set to 1, and the program is terminated.

On the other hand, if the result of the determination in step 80 is that the traction control signal STr is not being supplied, then in step 83 it is determined whether the operation mode flag Fd is 1 or not. If the operation mode flag Fd is 1, in step 84, after starting the built-in timer,
In step 85, the acceleration GN of the vehicle 1 calculated based on the change in the driven wheel rotation speed indicated by the detection output signal Sf is set to a predetermined value GN. Determine whether or not the above is true. As a result, the acceleration GN of the vehicle 1 becomes the predetermined value GN. If it is more than
In step 86, the built-in counter counts {II
X is increased by 1 and the process proceeds to step 87, and the acceleration GN of the vehicle 1 is set to a predetermined value GN.X. If it is less than that, proceed directly to step 87.

In step 87, it is determined whether or not the count value 'rt of the timer is greater than or equal to a predetermined value Ta. If the count value Tt of the timer is less than the predetermined value Ta, the process returns to step 85, and
When the count value Tt of the timer exceeds the predetermined value Ta, it is determined in step 88 whether the count value X of the counter is greater than or equal to the predetermined value X0. As a result of the determination in step 88, if the count value X of the force output is greater than or equal to the predetermined number and whether or not it indicates that a kickdown motion has been performed. As a result, the amount of depression of the accelerator pedal does not correspond to fully opening the accelerator pedal, and furthermore,
If there is no indication that a kickdown motion was made,
In step 90, the count value Tt of the timer is changed to the value Ta
It is determined whether or not the value is greater than or equal to a larger predetermined value Tb. If the count value Tt of the timer is less than the predetermined value Tb, the process proceeds to step 81, and if the count value Tt of the timer is greater than or equal to the predetermined value Tb, the operation mode flag Fd is set to 0 in step 91. Then, in step 92, the count value Tt of the counter is returned to 0, and then in step 93, a control mode is set in which the automatic transmission 9 performs a shift operation according to the shift operation characteristics for normal driving (CHNO). , exit the program.

Further, as a result of the determination in step 8, if the count value X of the counter is less than the predetermined number X0, or as a result of the determination in step 89, if the amount of depression of the accelerator pedal corresponds to fully opening the accelerator pedal, or, If it is determined that a kickdown operation has been performed, the process proceeds to step 92, and further, if the operation mode flag Fd is O as a result of the determination in step 83, directly,
Proceed to step 93.

In executing the program shown in the flowchart of FIG. 9, after starting, in step 90, it is determined whether traction control is in progress and the traction control signal STr is being supplied. As a result, if the traction control signal STr is supplied, step 91
At step 92, a control mode is set in which the automatic transmission 9 performs a shift operation according to the shift operation characteristics for traction control (CHTR), and at step 92, the operation mode flag Fe is set to 1, and the program is terminated. do.

On the other hand, if the result of the determination in step 90 is that the Traxigin control signal STr is not supplied, then in step 93 it is determined whether the operation mode flag Fe is 1 or not. If the operation mode flag Fe is 1, in step 94, after starting the built-in timer,
In step 95, the acceleration GN of the vehicle 1 calculated based on the change in the driven wheel rotation speed indicated by the detection output signal Sf is set to a predetermined value GN. Determine whether or not the above is true. As a result, the acceleration GN of the vehicle 1 becomes the predetermined value GN. If it is more than
In step 96, the count value X° of the built-in counter is incremented by 1, and the process proceeds to step 97. If the acceleration GN of the vehicle 1 is less than the predetermined value GN o, the process directly proceeds to step 97.

In step 97, it is determined whether the timer count value TL'' is greater than or equal to a predetermined value Ta. If the timer count value Tt' is less than the predetermined value Ta, the process returns to step 95, and the timer count value Tt' is less than the predetermined value Ta. When the numerical value Tt' exceeds the predetermined value Ta, in step 98, the count value Tt' of the timer is
After returning to 0, it is determined in step 99 whether the count value X' of the counter is greater than or equal to a predetermined number X0. As a result of the determination in step 99, if the count value X' of the counter is greater than or equal to the predetermined number and whether or not it indicates that a kickdown motion has been performed. As a result, if the amount of depression of the accelerator pedal does not correspond to the full opening of the accelerator pedal, and furthermore, it does not indicate that a kickdown operation has been performed, in step 101, the shift for normal driving is performed based on the variable lotus operation characteristics for traction control. It is determined whether or not the situation is such that a shift operation in the automatic transmission 9 is caused by a change in the operating characteristics.

As a result of the determination in step 101, if the automatic transmission 9 will perform a gear change operation, the process proceeds to step 91, and if the automatic transmission 9 does not result in a gear change operation, then After setting the operation mode flag Fe to O in step 102, in step 103 a control mode is set in which the automatic transmission 9 performs a shift operation in accordance with the shift operation characteristics for normal driving (CHNO), and the program ends.

Further, as a result of the determination in step 99, if the count value X° of the counter is less than the predetermined number or,
If it is determined that a kickdown operation has been performed, the process proceeds to step 103, and further, if the operation mode flag Fe is 0 as a result of the determination in step 93,
Proceed directly to step 103.

Note that in each of step 85 in the program shown in the flowchart of FIG. 8 and step 95 in the program shown in the flowchart of FIG. 9, the acceleration GN of the vehicle l is set to a predetermined value GN. However, in each of steps 85 and 95, instead of determining the acceleration GN, it is determined whether the negative acceleration, that is, the deceleration, of the vehicle 1 is less than or equal to a predetermined negative value. Alternatively, it may be determined whether the absolute value of acceleration or deceleration is greater than or equal to a predetermined value.

In executing the program shown in the flowchart of FIG. 10, after the start, in step 11O,
During traction control, the traction control signal ST
Determine whether r is supplied. As a result, if the traction control signal STr is supplied, in step 111, a control mode is set in which the automatic transmission 9 performs a shift operation according to the shift operation characteristic for traction control (CI{TR), and then in step 112 In this step, the operation mode flag Ff is set to 1, and the program ends.

On the other hand, if the result of the determination in step 110 is that the traction control signal STr is not supplied, then in step 113 it is determined whether the operation mode flag Ff is 1 or not. If the operation mode flag Ff is 1, it is determined in step 114 whether the vehicle speed Vf calculated based on the driven wheel rotation speed represented by the detection output signal Sf is less than a relatively small predetermined value 1. do. As a result, if the vehicle speed Vf is greater than the relatively small predetermined value ■1, it is determined in step 115 whether the vehicle speed r is greater than or equal to the relatively large predetermined value ■2.

If the result of the determination in step 114 is that the vehicle speed Vf is less than or equal to the relatively small predetermined value ■1, or if the result of the determination in step 115 is that the vehicle speed Vf is greater than or equal to the relatively large predetermined value ■2. In step 116, after starting the timer, in step 117, it is determined whether the amount of depression of the accelerator pedal indicated by the detection output signal Sa corresponds to fully opening the accelerator pedal, and
It is determined whether or not it indicates that a kickdown motion has been performed. As a result, if the amount of depression of the accelerator pedal does not correspond to the full opening of the accelerator pedal and further does not indicate that a kickdown operation has been performed, in step 118, the count value Tt'' of the timer is greater than or equal to the predetermined value Tc. Determine whether or not.

As a result of the determination in step 118, the count value T of the timer
t'' is less than the predetermined value Tc, step 11
If the count values T and I+ of the timer are greater than or equal to the predetermined value Tc, the operation mode flag Ff is set to O in step 119, and the process proceeds to step 1.
In step 20, the count value Tt'' of the timer is set to 0, and in step 121, a control mode is set in which the automatic transmission 9 performs a shift operation according to the shift operation characteristics for normal driving (CHNO), and the program is terminated. do.

Further, as a result of the determination in step 117, if the amount of depression of the accelerator pedal corresponds to fully opening the accelerator pedal,
Alternatively, if it indicates that a kickdown motion has been performed, proceed to step 120 and further proceed to step 113.
As a result of the judgment in step 115, if the operation mode flag Ff is O, if the result of the judgment in step 115 is that the vehicle speed f is less than a relatively large predetermined value Proceed to.

In executing the program shown in the flowchart of FIG. 11, after starting, in step 130,
Traction control is in progress and the traction control signal ST
Determine whether r is supplied. As a result, if the traction control signal STr is supplied, in step 131, a control mode is set in which the automatic transmission 9 performs a gear change operation according to the shift operation characteristics for traction control (CHTR), and in subsequent step 132, the automatic transmission 9 is operated. The mode flag Fg is set to 1 and the program ends.

On the other hand, if the result of the determination in step 130 is that the traction control signal STr is not being supplied, then in step 133 it is determined whether the operation mode flag Fg is 1 or not. If the operation mode flag Fg is 1, it is determined in step 134 whether the vehicle speed Vf calculated based on the driven wheel rotation speed indicated by the detection output signal Sf is less than a relatively small predetermined value 1. do. As a result, if the vehicle speed Vf is greater than the relatively small predetermined value (2), then in step 135 it is determined whether the vehicle speed Vf is greater than or equal to the relatively large predetermined value (2).

If the result of the determination in step 134 is that the vehicle speed Vf is less than or equal to the relatively small predetermined value ■1, or if the result of the determination in step 135 is that the vehicle speed Vf is greater than or equal to the relatively large predetermined value ■2. In step 136, whether or not the amount of depression of the accelerator pedal indicated by the detection output signal Sa corresponds to fully opening the accelerator pedal, and
It is determined whether or not it indicates that a kickdown motion has been performed. As a result, if the amount of depression of the accelerator pedal does not correspond to the full opening of the accelerator pedal and does not indicate that a kickdown operation has been performed, in step 137, the shift operation for normal driving is performed based on the shift operation characteristics for traction control. It is determined whether the situation is such that a change in the characteristics will cause a shift operation in the automatic transmission 9.

If the result of the determination in step 137 is that the automatic transmission 9 will undergo a gear change operation, the process proceeds to step 131, and if the automatic transmission 9 does not result in a gear change operation, then Step 138
After setting the operation mode flag Fg to 0 in step 139, a control mode is set in which the automatic transmission 9 performs a shift operation according to the shift operation characteristics for normal driving (CHNO), and the program ends.

Further, as a result of the determination in step 133, if the operation mode flag Fg is 0, as a result of the determination in step 135, the vehicle speed f is less than a relatively large predetermined value ■2, or as a result of the determination in step 136. As a result, if the amount of depression of the accelerator pedal corresponds to fully opening the accelerator pedal, or if it indicates that a kickdown operation has been performed, the process directly proceeds to step 139.

(Effects of the Invention) As is clear from the above description, the power train control device according to the present invention provides traction that reduces the torque transmitted from the power train to the drive wheels when the drive wheels slip on the road surface. The control is performed with the automatic transmission adopting a traction control shift characteristic that is different from the shift characteristic for normal driving, and after traction control is completed, the shift characteristic is changed from the traction control shift characteristic to the normal driving shift characteristic. When the steering angle is greater than a predetermined value, the lateral acceleration is greater than a predetermined value, or the coefficient of friction of the road surface is less than a predetermined value, at the end of traction control and thereafter. In this case, the change from the traction control shift characteristic to the normal driving shift characteristic is made when the steering angle is less than a predetermined value, the lateral acceleration is less than a predetermined value, or the friction coefficient of the road surface is greater than a predetermined value. or if it is determined that the road surface is rough, or if the vehicle speed is less than a relatively small predetermined value, or if the vehicle speed is greater than or equal to a relatively large predetermined value. , the change from the traction control shift characteristic to the normal driving shift characteristic is made until a predetermined period has elapsed from the time the traction control ended, or
This is prevented when a shift state is caused by changing the shift characteristic for traction control to the shift characteristic for normal driving. By doing this, after the traction control is finished,
A state in which the change from the transmission characteristic for traxigon control to the transmission characteristic for normal driving is carried out without causing wheel spin due to torque fluctuation, thereby avoiding a situation in which the driving stability of the vehicle is adversely affected. It can be done under

[Brief explanation of the drawing]

1A to 1E are basic configuration diagrams showing a power train control device according to the present invention in accordance with the claims, and FIG. 2 is an example of a power train control device according to the present invention, to which it is applied. FIGS. 3 and 4 are characteristic diagrams for explaining the operation of the example shown in FIG. 2, and FIGS. 3 is a flowchart showing examples of programs executed by a microcomputer used in a main control unit. In the figure, 1 is the vehicle, 2 is the front wheel, 3 is the rear wheel, 8 is the engine,
9 is an automatic transmission, 10 is a power train, l3 is a throttle actuator, 14 is a throttle valve, 22 is a first
, 23 is a second rotation speed sensor, 24 is a throttle opening sensor, 25 is an accelerator sensor, 26 is a steering angle sensor, 27 is a lateral acceleration sensor, 30 is a main control unit, and 40 is a sub-control unit. be. Figure 1 Figure 3 of t1

Claims (1)

[Scope of Claims] 1. Slip detection means for detecting slip of a drive wheel of a vehicle with respect to a road surface; and when the slip detected by the slip detection means is equal to or greater than a predetermined value, the drive wheel is removed from the power train of the vehicle. a torque control means that performs a torque reduction operation to reduce the torque transmitted to the wheels; and one that causes a gear change operation in an automatic transmission forming the power train to follow a first gear change characteristic when the torque reduction operation is performed. and a transmission characteristic changing means for performing a characteristic changing operation of changing the first transmission characteristic to a second transmission characteristic different from the first transmission characteristic after the torque reduction operation is completed; and a steering shaft of the vehicle. a steering angle detecting means for detecting a steering angle of the steering angle; and a steering angle detecting means for detecting a steering angle when the torque reducing operation is completed and thereafter, when the steering angle detected by the steering angle detecting means is a predetermined value or more, the shifting characteristic changing means. A powertrain control device comprising: characteristic change control means for inhibiting the characteristic change operation by; 2. Slip detection means for detecting slip of the driving wheels of the vehicle with respect to the road surface; and when the slip detected by the slip detection means is greater than or equal to a predetermined value, torque is transmitted from the power train of the vehicle to the driving wheels. a torque control means that performs a torque reduction operation to reduce the torque; and a gear change operation in an automatic transmission constituting the power train that follows a first shift characteristic when the torque reduction operation is performed, and the torque reduction operation transmission characteristic changing means for performing a characteristic changing operation of changing the first transmission characteristic to a second transmission characteristic different from the first transmission characteristic after the completion of the transmission; and a lateral acceleration acting on the vehicle. acceleration detecting means; when the torque reducing operation is completed and thereafter, if the lateral acceleration detected by the lateral acceleration detecting means is equal to or higher than a predetermined value, inhibiting the characteristic changing operation by the speed change characteristic changing means; A powertrain control device comprising: a characteristic change control means for controlling; and a powertrain control device. 3. Slip detection means for detecting slip of the driving wheels of the vehicle with respect to the road surface; and when the slip detected by the slip detection means is greater than or equal to a predetermined value, torque is transmitted from the power train of the vehicle to the driving wheels. a torque control means that performs a torque reduction operation to reduce the torque; and a gear change operation in an automatic transmission constituting the power train that follows a first shift characteristic when the torque reduction operation is performed, and the torque reduction operation transmission characteristic changing means for performing a characteristic changing operation of changing the first transmission characteristic to a second transmission characteristic different from the first transmission characteristic after the above-mentioned first transmission characteristic has been completed; and detecting a coefficient of friction of a road surface on which the vehicle runs. road surface friction coefficient detection means for detecting a road surface friction coefficient; A powertrain control device comprising: characteristic change control means for inhibiting the characteristic change operation. 4. Slip detection means for detecting slip of the drive wheels of the vehicle with respect to the road surface; and when the slip detected by the slip detection means is greater than or equal to a predetermined value, torque is transmitted from the power train of the vehicle to the drive wheels. a torque control means that performs a torque reduction operation to reduce the torque; and a gear change operation in an automatic transmission constituting the power train that follows a first shift characteristic when the torque reduction operation is performed, and the torque reduction operation a transmission characteristic changing means for performing a characteristic changing operation of changing the first transmission characteristic to a second transmission characteristic different from the first transmission characteristic after the completion of the transmission; and determining the condition of the road surface on which the vehicle runs. a road surface determination means; when the torque reduction operation is completed and thereafter, if the road surface determination means determines that the road surface is a rough road, a predetermined period of time has elapsed from the time the torque reduction operation was completed; or until the above
In the case where a shift state is brought about by changing the shift characteristic from the first shift characteristic to the second shift characteristic,
A powertrain control device comprising: characteristic change control means for inhibiting the characteristic change operation by the speed change characteristic change means. 5. Slip detection means for detecting slip of the driving wheels of the vehicle with respect to the road surface; and when the slip detected by the slip detection means is greater than or equal to a predetermined value, torque is transmitted from the power train of the vehicle to the driving wheels. a torque control means that performs a torque reduction operation to reduce the torque; and a gear change operation in an automatic transmission constituting the power train that follows a first shift characteristic when the torque reduction operation is performed, and the torque reduction operation transmission characteristic changing means for performing a characteristic changing operation of changing the first transmission characteristic to a second transmission characteristic different from the first transmission characteristic after the completion of the first transmission characteristic; and vehicle speed detection means for detecting the vehicle speed of the vehicle. When the torque reduction operation is completed and thereafter, if the vehicle speed detected by the vehicle speed detection means is less than or equal to a relatively small first value or greater than or equal to a relatively large second value, Until a predetermined period has elapsed since the end of the torque reduction operation, or when a shift state is brought about by changing from the first shift characteristic to the second shift characteristic. A powertrain control device comprising: characteristic change control means for inhibiting the characteristic change operation by the speed change characteristic change means.