JPH07108912A - Braking controller for vehicle - Google Patents

Abstract

PURPOSE:To prevent behavioral recovery carried out by automatically giving braking force to each wheel from interfering in the behavioral recovery carried out by a driving operation when behavioral abnormality occurs in a vehicle. CONSTITUTION:A behavior presuming section 72 presumes the behavior of a vehicle on its various moving state and operating states which are detected by a group of sensors 71. In the case of the behavioral abnormality of the vehicle, a target braking force determining section 75 cooperates with a braking force command computing 'section 73 to determine target braking force for recovering the behavioral abnormality. A valve control section 78 controls each of brake oil pressure controllers 30 to 60 according to the above determined target braking force to give the braking force to each wheel for recovering the behavior of the vehicle. A target braking force correcting section 76 detects the pressing down operation of an accel pedal through program processing on a throttle opening detected by a throttle sensor 77, and releases the automatic giving of the target braking force by setting the target braking force at zero in the case of detection.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a braking control device for a vehicle, which controls the application of a braking force to each wheel according to the behavior of the vehicle to stabilize the running of the vehicle.

[0002]

2. Description of the Related Art Conventionally, an apparatus of this type is disclosed in, for example, Japanese Patent Laid-Open No.
As disclosed in Japanese Patent Laid-Open No. 45452/1997, the behavior of a vehicle during traveling is detected, and a braking force according to the detected behavior of the vehicle is automatically applied to each wheel to improve traveling stability of the vehicle. I'm good.

[0003]

Although the braking control by the conventional device described above is effective for a normal driver, the automatic braking control may not be preferable for a skilled driver. That is, when the vehicle falls into a behavior abnormality such as spin or drift out, a normal driver depresses the brake pedal or releases the accelerator pedal so that the behavior of the vehicle is not further deteriorated. On the other hand, if the vehicle behavior is not fatal even in such a case, the skilled driver tries to restore the vehicle behavior by the will of the person by the balance between the depression operation of the accelerator pedal and the rotation operation of the steering handle. . Therefore, when a skilled driver is driving a vehicle, if automatic braking control for each wheel is performed according to the behavior of the vehicle as in the above-described conventional device, the automatic braking control is performed. Not only the automatic braking control and the driver's operation do not exert the effect on the running stability of the vehicle due to the interference with the operation of the vehicle to rebuild the vehicle's behavior by the driver's intention, but on the contrary, the stability is adversely affected. May bring.

The present invention has been made to solve the above problems, and an object of the present invention is to automatically detect a driving operation of the skilled driver for restoring the behavior of the vehicle, and at the time of the detection, the automatic braking is performed. It is an object of the present invention to provide a vehicle braking control device in which a part or all of the control is prohibited so as to avoid interference between the automatic braking control and the vehicle's intention of turning the vehicle over again.

[0005]

In order to achieve the above object, the structural features of the invention according to claim 1 are the behavior detecting means for detecting the behavior of the vehicle and the behavior of the detected vehicle. In a vehicle braking control device including a braking control unit that applies a braking force according to each wheel to stabilize vehicle traveling, an accelerator operation detection unit that detects an operation of an accelerator pedal and an operation of the accelerator pedal are detected. In this case, prohibiting means for prohibiting the application of the braking force to each wheel by the braking control means is provided.

In addition, the structural feature of the invention according to claim 2 is that the inhibiting means of the invention according to claim 1 applies the braking force to the drive wheels by the braking control means when the operation of the accelerator pedal is detected. Has been replaced by a prohibition means that prohibits.

[0007]

In the invention according to claim 1 configured as described above, even if the vehicle falls into abnormal behavior such as spin or drift out, the braking control means detects the behavior of the vehicle. By applying a braking force according to the behavior to each wheel, the behavior abnormality is automatically corrected,
Stabilize vehicle running. On the other hand, in the event of such a vehicle behavior abnormality, if the driver tries to restore the vehicle behavior by the balance between the depression operation of the accelerator pedal and the turning operation of the steering wheel, this accelerator pedal operation is detected as an accelerator operation detection. Detected by the braking means, the prohibiting means prohibits the braking control of each wheel by the braking control means in response to the detection of the operation of the accelerator pedal, so that the automatic braking control by the braking control means and the vehicle by the driver's intention. Interference with the re-building operation of is avoided. As a result, according to the invention of claim 1, in a state where the vehicle is in a behavior abnormality such as spin or drift-out, the driver restores the behavior of the vehicle by depressing the accelerator pedal and rotating the steering wheel. Even if the driver intends to do so or the driver does not perform the above operation, the traveling stability of the vehicle can be improved.

Further, in the invention according to claim 2 configured as described above, the driver depresses the accelerator pedal and rotates the steering wheel while the vehicle is in a behavior abnormality such as spin or drift out. When trying to restore the behavior of the vehicle by the balance of, in this case,
Since the prohibiting means prohibits the braking control of the driving wheels by the braking control means, it is possible to avoid the interference between the automatic braking control by the braking control means and the vehicle re-establishing operation using the driving wheels. In addition, since the behavior of the vehicle is restored by the depression operation of the accelerator pedal, it is directly related to the drive wheels. Therefore, the driving stability of the vehicle can be always improved by the invention according to the second aspect.

[0009]

【Example】

a. First Embodiment Hereinafter, a first embodiment of the present invention will be described with reference to the drawings.
FIG. 1 schematically shows a vehicular braking system according to the embodiment and a block diagram of an electric control system for controlling the vehicular braking system.

The vehicle braking device includes a master cylinder 13 that pumps the brake fluid boosted by the booster 12 from the first and second ports in response to the depression operation of the brake pedal 11. The first port of the master cylinder 13 communicates with the wheel cylinders 32 and 42 for the left and right front wheels via the valves 31 and 41 when the electromagnetic valves 31 and 41 are in the illustrated state. Further, the second port of the master cylinder 13 is connected to the electromagnetic valves 51, 61.
Is in the illustrated state, it also communicates with the left and right rear wheel wheel cylinders 52, 62 via the proportional valve 14 and both valves 51, 61, respectively.

A hydraulic pump 15 is connected to the booster 12, and the pump 15 stores oil pumped up from a reservoir 16 in an accumulator 17 and also supplies it to the booster 12. The discharge port of the booster 12 is the electromagnetic valve 2
When both 1 and 22 are in the illustrated state, both valves 2
High pressure oil passages L1 and L2 for front wheels and rear wheels via 1 and 22
Communicate with each. Further, the discharge port of the hydraulic pump 15 is such that when the electromagnetic valves 21 and 22 are switched from the illustrated state, the high pressure oil passages L1 and L1 are connected via the valves 21 and 22.
It also communicates with L2 respectively. The brake hydraulic pressure control device 30 for the left front wheel includes an electromagnetic valve 33 for pressure increase and an electromagnetic valve 34 for pressure reduction in addition to the electromagnetic valve 31 and the wheel cylinder 32 described above. The electromagnetic valve 33 allows the high-pressure oil passage L1 to communicate with the wheel cylinder 32 in the illustrated state when the electromagnetic valve 31 is switched from the illustrated state, and prohibits the communication when the electromagnetic valve 31 is switched from the illustrated state. When the electromagnetic valve 31 is switched from the illustrated state, the electromagnetic valve 34 stores the wheel cylinder 32 in the reservoir 16 in the switched state from the illustrated state.
Is communicated with the low pressure oil passage L2 that is communicated with and is prohibited in the illustrated state.

The brake hydraulic control device 40 for the right front wheel is also provided with electromagnetic valves 43 and 44 which function in the same manner as the brake hydraulic control device 30 for the left front wheel, in addition to the above-mentioned electromagnetic valve 41 and wheel cylinder 42. There is. The brake hydraulic control device 50 for the left rear wheel is also the electromagnetic valve 5 described above.
In addition to 1 and the wheel cylinder 52, electromagnetic valves 53 and 54 that function similarly to the case of the brake hydraulic control device 30 for the left front wheel are provided. The brake hydraulic pressure control device 60 for the right rear wheel also includes electromagnetic valves 63 and 64 that function in the same manner as the brake hydraulic pressure control device 30 for the left front wheel, in addition to the electromagnetic valve 61 and the wheel cylinder 62 described above. However, the brake hydraulic devices 50, 60 for the left and right rear wheels
In the above, the electromagnetic valves 53, 63 for increasing pressure are high pressure oil passages.
It is connected to L2. The above-mentioned electromagnetic valves are maintained in the illustrated state in the non-energized state, and are switched from the illustrated state by energizing.

Next, an electric control device for controlling these electromagnetic valves will be described. The electric control device is incorporated in each brake hydraulic pressure control device 30, 40, 50, 60, respectively, and is provided in each wheel cylinder 32, 42, 52, 6 respectively.
The hydraulic pressure sensors 35, 45, 55, 6 that detect the brake hydraulic pressure applied to 2 and output a detection signal representing the hydraulic pressure.
It is equipped with 5. Further, the electric control device includes a sensor group 71 including a plurality of sensors that detect a vehicle motion state amount such as a vehicle speed, a longitudinal acceleration, a lateral acceleration, a yaw rate, and a vehicle body slip angle, and a vehicle operating state amount such as a steering angle. I have it. A behavior estimating unit 72 is connected to the sensor group 71, and the estimating unit 72 uses the detection signals from the sensor group 71 to determine the behavior of the vehicle (total vehicle motion state).
And outputs a signal representing the same behavior. A braking force command calculation unit 73 is connected to the behavior estimation unit 72, and the calculation unit 73 detects a vehicle behavior abnormality such as spin or drift out based on the estimated vehicle behavior,
When the abnormality is detected, an operation instruction signal for instructing their operation is output to a target braking force determination unit 75, a target braking force correction unit 76, and a valve control unit 78, which will be described later, and a braking force is applied to each wheel. Signals representing the total braking force and the front-rear distribution ratio and the left-right distribution ratio of the same braking force are output to the gain control circuits 74a to 74c, respectively. The gain control circuits 74a to 74c control the gains of the supplied signals and supply them to the target braking force determination unit 75. Target braking force determination unit 7
The reference numeral 5 designates a target control for the left and right front wheels and the left and right rear wheels based on the gain-controlled signals representing the total braking force, the front-rear distribution ratio and the left-right distribution ratio, which are activated by the arrival of the operation instruction signal from the braking force command calculation unit 73. Calculate the power F _FL , F _FR , F _RL , F _RR ,
The signals representing the calculated target braking forces F _FL , F _FR , F _RL , and F _RR are output to the target braking force correction unit 76.

A throttle sensor 77 is also connected to the target braking force correction unit 76, and the sensor 77 detects the throttle opening corresponding to the depression amount of the accelerator pedal and outputs a detection signal indicating the throttle opening. To do. The target braking force correction unit 76 is composed of a microcomputer or the like, and operates by the arrival of an operation instruction signal from the braking force command calculation unit 73, and corresponds to the flowchart shown in FIG. 2 under the control of a built-in timer circuit. The program is executed every predetermined time to correct the target braking forces F _FL , F _FR , F _RL , and F _RR and output it to the valve control unit 78. Valve control unit 78
Also actuated by the arrival of the actuation instruction signal from the braking force command calculation unit 73, and the corrected target braking forces F _FL , F _FR ,
Target hydraulic pressures corresponding to F _RL and F _RR and hydraulic pressure sensors 35, 4
Based on the comparison with the detected hydraulic pressures fed back from 5, 55, 65, the electromagnetic valves are controlled to set the hydraulic pressures applied to the wheel cylinders 32, 42, 52, 62 to the target hydraulic pressures.

Next, the operation of the embodiment configured as described above will be described. Brake pedal 1 while the driver is driving the vehicle
When 1 is depressed, the brake hydraulic pressure boosted by the booster 12 is discharged from the first and second ports of the master cylinder 13. If the behavior of the vehicle is normal and the wheels are not likely to lock at the same time, all the electromagnetic valves are in the illustrated state. Therefore, in this case, the brake oil pressure from the first port is supplied to the wheel cylinders 32, 42 via the electromagnetic valves 31, 41, and
The brake hydraulic pressure from the second port is supplied to the wheel cylinders 52 and 62 via the proportional valve 14 and the electromagnetic valves 51 and 61. As a result, in this case, the braking force according to the depression operation of the brake pedal 11 is applied to each wheel, and the vehicle is braked.

On the other hand, when the wheels are likely to be locked by the depression operation of the brake pedal even if the behavior of the vehicle is normal, the electromagnetic valves 31, 41, 51, 61 are changed from the illustrated state by the antilock control circuit (not shown). Switching is controlled. Therefore, the supply and discharge of the brake hydraulic pressure to and from the wheel cylinders 32, 42, 52, 62 corresponding to the respective wheels are performed by the electromagnetic valves 33, 34, 43, 44, 5 respectively.
It is placed under the control of 3, 54, 63, 64. Then, the anti-lock control circuit causes the electromagnetic valves 33, 34, 43, 44, 53, 54, 63, 6 according to the locked state of each wheel.
By controlling the switching of No. 4, the pressure increase, the pressure decrease, and the holding of the brake fluid with respect to the wheel cylinders 32, 42, 52, 62 are controlled respectively, and the locking of each wheel is avoided. Since such anti-lock control is not directly related to this case, detailed description will be omitted.

When the behavior of the vehicle is not normal,
The braking force command calculation unit 73 includes the sensor group 71 and the behavior estimation unit 7.
The vehicle behavior abnormality is detected based on the vehicle behavior state estimated in cooperation with the vehicle 2 and the operation instruction signal is output to the target braking force determination unit 75, the target braking force correction unit 76, and the valve control unit 78. Then, the respective parts 75, 76, 78 are actuated, and signals representing the total braking force for applying the braking force to each wheel and the front-rear distribution ratio and the left-right distribution ratio of the braking force are supplied to the gain control circuits 74a to 74c. It outputs to the target braking force determination unit 75 via the. The target braking force determination unit 75 uses the gain-controlled total braking force, the front-rear distribution ratio, and the left-right distribution ratio based on the respective signals to set the target braking force F _{FL of} the left and right front wheels and the rear left and right wheels.
F _FR , F _RL , F _RR are determined, and the determined target braking force F is determined.
Signals representing _FL , F _FR , F _RL , and F _RR are applied to the target braking force correction unit 7
Output to 6.

On the other hand, the target braking force correction unit 76 receives the operation instruction from the braking force command calculation unit 73 and executes step 100 of FIG.
The program consisting of 142 is repeatedly executed every predetermined short time. At the start of the program, a flag Fman indicating the driver's intention to restore the vehicle behavior abnormality by depressing the accelerator pedal and rotating the steering wheel, and the time for measuring the time from the cancellation of the both operations. The count value Tcnt is initialized to "0", and the target braking forces F _FL , F _FR , F
The correction coefficient Kx for _RL and F _RR is initialized to "1". In executing the program, step 102
At throttle opening θ and target braking force F _FL , F _FR , F
Input signals representing _RL and F _RR . Then, step 104
By differentiating the inputted throttle opening θ at, the change speed dθ / dt of the throttle opening corresponding to the accelerator pedal depression speed is calculated, and step 106
Then, the index value θr for determining the depression operation of the accelerator pedal is calculated by executing the calculation of the following Expression 1.

[0019]

## EQU1 ## θr = θ + K ₁ · dθ / dt where the coefficient K ₁ is a predetermined constant.

First, since the flag Fman is set to "0" and the correction coefficient Kx is set to "1", it is judged "YES" at both steps 108 and 110, and at step 112. After resetting the correction coefficient Kx to "1", in step 116, the index value θr is compared with the threshold value θ ₁ indicating the driver's intention of depressing the accelerator pedal. If the index value θr is smaller than the threshold value θ ₁ , it is determined to be “NO” in step 116 and the program proceeds to steps 138 and 140. Step 13
In step 8, the target braking forces F _FL , F _FR , F _RL , and F _RR are corrected by multiplying them by the correction coefficient Kx set to "1", respectively, and in step 140, the corrected target braking forces are corrected. The powers F _FL *, F _FR *, F _RL *, F _RR * are output to the valve controller 78. In this case, the corrected target braking forces F _FL *, F _FR *, F _RL *, F _RR * are equal to the uncorrected target braking forces F _FL , F _FR , F _RL , F _RR .

The valve control unit 78 is fed back from the respective target hydraulic pressures corresponding to the corrected target braking forces F _FL *, F _FR *, F _RL *, F _RR * and the hydraulic pressure sensors 35, 45, 55, 65. The respective wheel valves 32, 42, 52, 6 are controlled by controlling each electromagnetic valve based on the comparison result with each detected hydraulic pressure.
The hydraulic pressure applied to 2 is set and controlled to each target hydraulic pressure. The control of each electromagnetic valve will be described by taking the left front wheel as an example. First, the valve control unit 78 energizes the electromagnetic valves 21 and 31 to switch the valves 21 and 31 from the illustrated state. Therefore, the high-pressure oil discharged by the hydraulic pump 15 and accumulated in the accumulator 17 is supplied to the high-pressure oil passage L1, and the brake oil pressure in the wheel cylinder 32 is under the control of the electromagnetic valves 33, 34.

If the target oil pressure is higher than the oil pressure detected by the oil pressure sensor 35, the electromagnetic valves 33 and 34 are kept in the non-energized state. As a result, the electromagnetic valves 33, 34 are kept in the illustrated state, and the high-pressure oil supplied to the high-pressure oil passage L1 is supplied to the wheel cylinders 32 via the electromagnetic valves 21, 33, 31. The hydraulic pressure rises toward the target hydraulic pressure. On the other hand, if the target hydraulic pressure is lower than the detected hydraulic pressure, the electromagnetic valves 33 and 34 are energized. As a result, the electromagnetic valves 33, 34 are switched from the illustrated state, and the brake oil in the wheel cylinder 32 is discharged to the reservoir 16 via the low pressure oil passage L3, so that the brake oil pressure in the cylinder 32 moves toward the target oil pressure. To descend.
If the target hydraulic pressure and the detected hydraulic pressure become equal by these controls, the electromagnetic valve 33 is energized and the electromagnetic valve 34 is turned on.
Is set to the non-energized state. As a result, the electromagnetic valve 33
Is switched from the illustrated state and the electromagnetic valve 34 is maintained in the illustrated state, so that the brake oil in the wheel cylinder 32 is retained and the brake hydraulic pressure of the cylinder 32 is maintained at the target hydraulic pressure.

Since the brake hydraulic pressure in the wheel cylinder 32 is set to the target hydraulic pressure in this way, the braking force of the left front wheel is corrected to the corrected target braking force F _FL * (pre-corrected target braking force F _FL) . Controlled). In addition, similarly,
The braking force for the right front wheel and the left and right rear wheels is also set to the corrected target braking force F _FR *, F _RL *, F _RR * (equal to the target braking force F _FR , F _RL , F _RR before correction). It as a result,
Even if the vehicle behavior is abnormal, if the driver does not try to recover the vehicle behavior abnormality by depressing the accelerator pedal or turning the steering handle, the target braking force determination unit 75 Target braking force F determined by
The automatic behavior of _FL , F _FR , F _RL , and F _RR corrects the abnormal behavior of the vehicle and improves the running stability of the vehicle. Of course, if the vehicle behavior abnormality has not occurred, the target braking force determination unit 75, the target braking force correction unit 76, and the valve control unit 7
Since 8 is not operating, the target braking force is not automatically applied to each wheel.

Next, a case will be described in which a skilled driver recovers an abnormal vehicle behavior by depressing the accelerator pedal and turning the steering wheel. Time t1 in FIG.
When the index value θr becomes equal to or greater than the threshold value θ ₁ due to an increase in the accelerator pedal operation amount by the driver, step 11
At step 118, the flag Fman is set to "1" and the time count value Tcnt is initialized to "0" at step 120. When the flag Fman is set to "1" in this way, it is determined to be "NO" at step 108 when the next program is executed, and the program proceeds to step 122 and thereafter. If the correction coefficient Kx is larger than “0”, the correction coefficient Kx is decreased by a predetermined minute value ΔK in step 124 based on the determination of “NO” in step 122.
Since these processes are performed every time the program is executed until the correction coefficient Kx becomes "0", the correction coefficient Kx gradually decreases toward "0". And the time in FIG.
As shown by t2, when the correction coefficient Kx becomes "0", the correction coefficient Kx is held at "0" at step 126 based on the determination of "YES" at step 122.

In this way, the correction coefficient Kx which gradually changes from "1" to "0" and thereafter is held at "0" is the target braking force F _FL , which is input in step 138.
The target braking force F _FL *, F multiplied by F _FR , F _RL , F _RR and corrected by the correction coefficient Kx in step 140
_FR *, _FRL *, and _FRR * are output to the valve control unit 78.
Therefore, the target braking forces F _FL , F _FR , F _RL , and F _RR determined by the target braking force determiner 75 are gradually corrected toward “0” and maintained at “0” thereafter. Since it is corrected and output as corrected target braking forces F _FL *, F _FR *, F _RL *, F _RR *, the brake hydraulic pressure in the wheel cylinders 32, 42, 52, 62 set by the valve control unit 78. Gradually changes toward "0" and thereafter "0"
Will be maintained. As a result, the automatic application of the target braking forces F _FL , F _FR , F _RL , and F _{RR to} each wheel is gradually prohibited, and a skilled driver depresses the accelerator pedal to restore the abnormal vehicle behavior. Moreover, even if the steering wheel is rotated, it is possible to avoid the interference between the operation of the driver and the automatic application of the target braking forces F _FL , F _FR , F _RL and F _RR . Therefore, in this case, the behavior of the vehicle is accurately restored by the driver's depressing operation of the accelerator pedal and rotating operation of the steering wheel.

When the driver depresses the accelerator pedal to restore the vehicle behavior and the index value θr becomes less than or equal to the threshold value θ ₂ as shown at time t3 in FIG. 3, step 128 is performed. In step 132, the time count value Tcnt and the predetermined value To are compared with each other. This time count value Tcnt has the index value θr set to the threshold value θ by the processing of steps 128 and 130.
Since it was kept at "0" until it became ₂ or less, immediately after time t3, it was judged as "NO" at step 132,
The time count value Tcnt is incremented by "1" by the processing of step 134 each time this program is executed. When the time count value Tcnt reaches the predetermined value To (see time t4 in FIG. 3), the flag Fman is reset to "0" in step 136 based on the determination of "YES" in step 132. As a result, by the processing of steps 108, 110, 114, the correction coefficient Kx is kept until the coefficient Kx becomes "1".
Each time this program is executed, it is incremented by a minute value ΔK. When the correction coefficient Kx becomes "1" as shown at time t5 in FIG.
It is maintained at "1" by the processing of 0,112. Therefore, the correction coefficient Kx gradually changes from "0" to "1", and by the processing of steps 138 and 140, the target value determined by the target braking force determination unit 75 is set to "0" by the valve control unit 78. A signal that gradually changes toward the braking forces F _FL , F _FR , F _RL , and F _RR is supplied. As a result, the prohibition of automatic _application of the target braking forces F _FL , F _FR , F _RL , and F _RR is gradually released, and the target braking forces F _FL , F _FR , and F _RL corresponding to the behavior of the vehicle are applied to each wheel. , F _RR will be automatically _added again. Of course, if the behavior abnormality of the vehicle is corrected by the driver's operation of the accelerator pedal and the steering wheel, the target braking force determination unit 75, the target braking force correction unit 76, and the valve control unit 78 are not operating. Braking force is not automatically applied to the wheels.

In the first embodiment described above, the amount of depression of the accelerator pedal is detected by detecting the throttle opening θ, but by detecting the rotation angle of the accelerator pedal, the pedal operation amount of the pedal can be detected. The amount of stepping operation may be directly detected.

In the above embodiment, the behavior estimating section 72, the braking force command calculating section 73, the gain control circuits 74a.about.
Although 74c, the target braking force determination unit 75, and the valve control unit 78 are shown to be configured by hardware circuits, each of these circuits can be implemented by software processing such as a microcomputer as appropriate. Further, in the above-described embodiment, the target braking force correction unit 76 is configured by the microcomputer that executes the software process, but a part or all of the software process may be processed by the hardware circuit.

B. Second Embodiment Next, a second embodiment of the present invention will be described. This second
The vehicle according to the embodiment is premised on a rear-wheel-drive two-wheel drive vehicle, and the vehicle braking device and the electric control device for the device of the embodiment are configured in the same manner as in the above-described embodiment. ing. However, the program executed by the target braking force correction unit 76 is, as shown in the flowchart of FIG. 4, step 138 of the flowchart of FIG. 2 of the first embodiment described above,
The processing of 140 is replaced with the processing of steps 138a and 140a.

In this case, in step 138a,
Only the target braking forces F _RL and F _RR regarding the rear wheels as the driving wheels determined by the target braking force determination unit 75 are corrected by the correction coefficient Kx.
_Is corrected to target braking forces F _RL *, F _RR *. Then, in step 140a, the corrected target braking forces F _RL *, F _RR * and the uncorrected target braking forces F _FL , F _FR for the front wheels that are non-driving wheels are set to the valve controller 78.
Is output to. As a result, according to the second embodiment, when an abnormality occurs in the behavior of the vehicle and the driver attempts to restore the behavior of the vehicle by depressing the accelerator pedal and rotating the steering handle, the vehicle is used as a driving wheel. Only the automatic application of the target braking force to the rear wheels is released, and the target braking forces F _FL and F _FR determined by the target braking force determination unit 75 are automatically applied to the front wheels as the non-driving wheels as they are (FIG. 5). reference). The rest of the operation is the same as in the first embodiment. In this case, since the restoration of the behavior by depressing the accelerator pedal is directly related to the driving wheels,
According to the embodiment, there is no interference between the restoration of the vehicle behavior by the driver's driving operation and the restoration of the vehicle behavior by the automatic application of the target braking force, and the traveling stability of the vehicle is always maintained by the restoration of both vehicle behaviors. Can be good.

In the second embodiment, the case where the rear wheels are the drive wheels and the front wheels are the non-drive wheels has been described. However, the present invention is applicable to a vehicle in which the front wheels are the drive wheels and the rear wheels are the non-drive wheels. Can also be applied. In this case, when an abnormality occurs in the behavior of the vehicle and the driver attempts to rebuild the behavior of the vehicle by depressing the accelerator pedal and rotating the steering wheel, only the automatic application of the target braking force to the front wheels is released, The target braking forces F _FL and F _FR determined by the target braking force determiner 75 may be automatically applied to the rear wheels as they are.

C. Third Embodiment Next, a third embodiment of the present invention will be described. This third
The vehicle according to the embodiment is also premised on a rear-wheel drive type two-wheel drive vehicle. In the third embodiment, as shown in the flow chart of FIG. 6, steps 150 to 142 are performed before steps 138 to 142 of the flow chart of FIG. 2 of the first embodiment.
The processing of 158 is inserted, and the same steps 138 to 14 are executed.
The process of No. 2 is changed as in steps 138a to 142.

In this case, in step 150, the target braking forces F _FL , F _FR for the left and right front wheels, which are non-driving wheels, are set.
A value obtained by multiplying the smaller one by the correction coefficient Kx is determined as the first correction target braking force F _MIN = K _X MIN (F _FL , F _FR ). In step 152, both target braking forces F _FL , F
A value obtained by adding the first correction target braking force F _MIN to the absolute value of the difference between _FRs is the second correction target braking force F _MAX = | F _FL −F _FR | +
Determined as F _MIN . Therefore, when an abnormality occurs in the behavior of the vehicle and the driver tries to restore the behavior of the vehicle by depressing the accelerator pedal and rotating the steering wheel, the first correction target braking force F _MIN changes in the correction coefficient Kx. Gradually changed to "0" according to
The second correction target braking force F _MAX is gradually changed to the absolute value of the difference between the two target braking forces F _FL and F _FR | F as the correction coefficient Kx changes.
Change to _FL- F _FR |. Next, steps 154-1
If the target braking force F _FL for the left front wheel is equal to or _larger than the target braking force F _FR for the right front wheel by the processing of 8, the corrected target braking force F _FL * for the left front wheel is set to the second corrected target braking force F _MAX. Also, the target braking force F _FR * for the right front wheel
Is set to the first corrected target braking force F _MIN . If the target braking force F _FL for the left front wheel is smaller than the target braking force F _FR for the right front wheel, the corrected target braking force F for the left front wheel F
_FL * is set to the first corrected target braking force F _MIN , and
The target braking force F _FR * for the right front wheel is set to the second corrected target braking force F _MAX . Therefore, in the corrected target braking forces F _FL * and F _FR * for the left and right front wheels, the smaller one is gradually changed to “0” as the correction coefficient Kx changes,
The larger value gradually changes to the absolute value | F _FL −F _FR | of the difference between the two target braking forces F _FL and F _{FR as} the correction coefficient Kx changes (see FIG. 7).

When the driver tries to correct the vehicle behavior abnormality by depressing the accelerator pedal and rotating the steering wheel, the target braking forces F _RL and F _RR of the rear wheels, which are the driving wheels, are the above-mentioned As in the first and second embodiments, the processing of step 138a gradually changes to "0" according to the change of the correction coefficient Kx. As a result, also in the third embodiment, there is no interference between the restoration of the vehicle behavior caused by the driver's driving operation and the restoration of the vehicle behavior caused by the automatic application of the target braking force, and the vehicle behavior is restored by the restoration of both vehicle behaviors. The running stability can always be improved.

Further, according to the third embodiment, the automatic _application of the target braking forces F _FL , F _{FR to} the front wheels which are non-driving wheels is suppressed while maintaining the difference in the braking forces between the left and right front wheels. Therefore, the wheel speed of the front wheels can be accurately detected in order to detect the slip ratio without impairing the braking force applying function for rebuilding the behavior of the vehicle. That is, the difference in rotational speed between the normal driving wheel and the non-driving wheel is used to detect the slip ratio, but in the second embodiment, the target braking force determination unit 75 determines all the non-driving wheels. The target braking force is applied, and the slip ratio is not accurately detected.
On the other hand, according to the third embodiment, a state in which the target braking force is not automatically applied to at least one of the left and right front wheels with respect to the front wheel can be realized, and the slip ratio can be accurately detected. Since the detected slip ratio is used for traction control or the like, the control can be accurately performed.

In the third embodiment as well, the case where the rear wheels are the driving wheels and the front wheels are the non-driving wheels has been described. However, in the release control of the target braking force, the front wheels are the driving wheels and the rear wheels are the driving wheels. It can also be applied to vehicles with non-driving wheels. Also in this case, similarly to the second embodiment, the various calculations of the above embodiment may be reversed for the front wheels and the rear wheels.

[Brief description of drawings]

FIG. 1 is a diagram schematically showing a vehicle braking device according to first to third embodiments of the present invention and an electric control device for the same.

FIG. 2 is a flowchart of a program executed by the target braking force correction unit of FIG. 1 according to the first embodiment of the present invention.

FIG. 3 is a throttle opening according to the first embodiment of the present invention;
It is a time chart which shows a change state, such as a correction coefficient and target braking force.

FIG. 4 is a part of a flowchart of a program executed by the target braking force correction section of FIG. 1 according to the second embodiment of the present invention.

FIG. 5 is a throttle opening according to a second embodiment of the present invention,
It is a time chart which shows a change state, such as a correction coefficient and target braking force.

FIG. 6 is a part of a flowchart of a program executed by the target braking force correction unit of FIG. 1 according to the third embodiment of the present invention.

FIG. 7 is a throttle opening according to a third embodiment of the present invention;
It is a time chart which shows a change state, such as a correction coefficient and target braking force.

[Explanation of symbols]

11 ... Brake pedal, 12 ... Booster, 13 ... Master cylinder, 15 ... Hydraulic pump, 21, 22 ... Electromagnetic valve (braking control means), 30 ... Left front wheel brake hydraulic control device (braking control means), 40 ... Right Brake hydraulic pressure control device for front wheel (braking control means), 50 ... Brake hydraulic pressure control device for left rear wheel (braking control means), 60 ... Brake hydraulic pressure control device for right rear wheel (braking control means), 32, 42 , 5
2, 62 ... Wheel cylinder (braking control means), 71 ...
Sensor group (behavior detection means), 72 ... Behavior estimation section (behavior detection means), 73 ... Braking force command calculation section (braking control means),
75 ... Target braking force determination unit (braking control means), 76 ... Target braking force correction unit (accelerator operation detection means, prohibition means), 7
7 ... Throttle sensor (accelerator operation detecting means), 78
... Valve control section (braking control means).

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Noriaki Hattori 2-1, Asahi-cho, Kariya city, Aichi Prefecture Aisin Seiki Co., Ltd. (72) Kenji Totsu 2-1-1, Asahi-cho, Kariya city, Aichi Prefecture Aisin In Seiki Co., Ltd. (72) Inventor Jun Mihara 2-1-1 Asahi-cho, Kariya city, Aichi Prefecture Aisin Seiki Co., Ltd. (72) In-house Takayuki Ito 2-1-1 Asahi-cho, Kariya city, Aichi Aisin Seiki Co., Ltd. (72) Inventor Shingo Sugiura 2-1-1 Asahi-cho, Kariya-shi, Aichi Aisin Seiki Co., Ltd. (72) In-house Norio Yamazaki 2-1-1 Asahi-cho, Kariya-shi, Aichi Aisin Seiki Co., Ltd.

Claims (2)

[Claims] 1. Behavior detecting means for detecting the behavior of a vehicle,
A braking control device for a vehicle, comprising: a braking control means for applying a braking force corresponding to the detected vehicle behavior to each wheel to stabilize the vehicle running; and an accelerator operation detection means for detecting an operation of an accelerator pedal, A braking control device for a vehicle, further comprising: a prohibiting unit that prohibits application of a braking force to each wheel by the braking control unit when an operation of the accelerator pedal is detected. 2. Behavior detecting means for detecting the behavior of the vehicle,
A braking control device for a vehicle, comprising: a braking control means for applying a braking force corresponding to the detected vehicle behavior to each wheel to stabilize the vehicle running; and an accelerator operation detection means for detecting an operation of an accelerator pedal, A braking control device for a vehicle, comprising: a prohibiting unit that prohibits application of a braking force to the driving wheels by the braking control unit when an operation of the accelerator pedal is detected.