JPH0880824A - Behavior controller of vehicle - Google Patents

Abstract

PURPOSE: To prevent the worsening of the responsiveness of behavior control due to knock by detecting or surmising lateral force to act on each vehicle wheel, conducting change by means of a pressure increase time changing means so that the larger lateral force at the pressure increase time of a hydraulic control means is, the longer a pressure increase time may become. CONSTITUTION: An electric type controller 50 consists of a micro computer 52 and a drive circuit 54, and signals from a vehicle speed sensor 56, a lateral acceleration sensor 58, a yaw rate sensor 60 and vehicle wheel speed sensors 64FL-64RR are inputted into the micro computer 52 respectively, and a sudden pressure increase time Tfa is operated on the basis of the absolute value of lateral acceleration Gy by means of the lateral acceleration sensor 58 of a vehicle body during turning behavior control. In this instance, the sudden pressure increase time Tfa is operated so that the larger the absolute value of the vehicle body lateral acceleration Gy is, that is, the larger lateral force to act on each vehicle wheel is, the longer it may become, and the pressure increase of a wheel cylinder 38FL or 38FR is conducted. As a result, regardless of the size of lateral force, the control of turning movement can be executed without the delay of response.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a behavior control device for suppressing and reducing undesirable behavior such as drift-out and spin of a vehicle such as an automobile, and more particularly to controlling undesirable braking behavior by controlling the braking force of wheels. The present invention relates to a behavior control device that suppresses and reduces.

[0002]

2. Description of the Related Art As one of the devices for controlling the behavior of a vehicle such as an automobile when the vehicle turns, for example, Japanese Patent Laid-Open No. 3-4545.
As described in Japanese Patent Publication No. 3, a steering amount detecting means, a vehicle speed detecting means, a yaw rate detecting means, a limit vehicle speed detecting means for obtaining a tire grip limit vehicle speed according to a steering amount, a steering amount and a tire grip. A target yaw rate setting means for obtaining a target yaw rate corresponding to the limit vehicle speed and a braking means provided for each wheel are provided, and when the vehicle speed exceeds the grip limit vehicle speed of the tire, the yaw rate approaches the target yaw rate. A behavior control device configured to control the braking force of a turning inner wheel and an outer wheel so as to reduce the vehicle speed to a limit vehicle speed has been conventionally known.

According to such a behavior control device, the vehicle can always run in the grip area of the tire, and the yaw rate can be prevented from exceeding the target yaw rate, thereby preventing the vehicle from spinning or drifting out. The turning behavior can be prevented.

[0004]

In the conventional behavior control device described in the above publication, the braking force is automatically applied when the vehicle speed exceeds the grip limit vehicle speed of the tire. There is a predetermined gap between the brake mechanism provided on each wheel, for example, between the brake rotor and the pad or between the pad and the caliper during non-braking, so the brake oil amount-actual braking pressure characteristic of each brake mechanism is Figure 9
As shown by the solid line, there is a dead zone area where the actual braking pressure does not substantially increase even if the brake oil quantity increases.Therefore, when starting the behavior control, the brake oil quantity should exceed the dead zone area. The pressure in the wheel cylinder needs to be increased rapidly.

However, when the vehicle turns, a relatively large lateral force acts on the wheels, and when a large lateral force acts on the wheels, so-called knockback causes a gap between the brake rotor and the pad or between the pad and the caliper. Will increase. As a result, the dead zone region also increases as shown by the phantom line in FIG. 9, so that even if the pressure in the wheel cylinder is increased for a certain time at the start of the behavior control, it is necessary and sufficient for controlling the turning behavior. There is a problem that it is not possible to generate various braking pressures with good responsiveness.

Further, in order to solve such a problem, if the time during which the pressure in the wheel cylinder is increased at the start of the behavior control is set to a relatively long constant time, knockback occurs when the lateral force acting on the wheel is small. Since the influence of is small, the braking pressure rises excessively above the pressure required for the behavior control, which causes a problem that the behavior control cannot be optimally executed.

The present invention has been made in view of the above-mentioned problems in the conventional behavior control device, and the main object of the present invention is to control the behavior according to the magnitude of the lateral force acting on the wheel. By optimizing the pressure increase time at the start, deterioration of the response of the behavior control due to knockback is prevented and the behavior control is optimally executed.

[0008]

According to the present invention, the main problem as described above is achieved by the structure of claim 1, namely, a master cylinder, a hydraulic pressure source, a wheel cylinder provided on each wheel, and a vehicle. Means for detecting the traveling state of the wheel cylinder, and when the detected traveling state is unstable, the hydraulic pressure in the wheel cylinder is controlled according to the traveling state by controlling the supply and discharge of high hydraulic pressure from the hydraulic pressure generation source to the wheel cylinder. In a vehicle behavior control device having a hydraulic control means for increasing and decreasing, a means for detecting or estimating a lateral force acting on the wheel and a greater lateral force at the start of pressure increase by the hydraulic control means And a pressure increase time changing means for changing the pressure increase time so that the pressure increase time by the hydraulic pressure control means becomes longer.

According to the present invention, in order to effectively achieve the above-mentioned main problem, in the structure of claim 1, the hydraulic pressure is supplied from the master cylinder to the wheel cylinder. When the pressure increase by the hydraulic pressure control means is started by the pressure control means, there is provided means for prohibiting the change of the pressure increase time by the pressure increase time changing means (configuration of claim 2).

[0010]

According to the first aspect of the present invention, the lateral force acting on the wheel is detected or estimated, and the larger the lateral force at the start of pressure increase by the hydraulic control means, that is, the amount of brake oil-actual braking pressure. The pressure increasing time is changed by the pressure increasing time changing means so that the pressure increasing time by the hydraulic control means becomes longer as the dead zone of the characteristic becomes larger. It is possible to reliably prevent a sudden increase in the pressure of, and thereby to prevent the responsiveness of the behavior control from being deteriorated due to knockback.

Further, when the hydraulic pressure from the master cylinder is being supplied to the wheel cylinder, the brake rotor and the pad, the pad and the caliper are in contact with each other, and the braking pressure corresponding to the hydraulic pressure from the master cylinder is applied. Therefore, even in such a situation, when the pressure increasing time is changed according to the configuration of claim 1 and the pressure in the wheel cylinder is increased by the hydraulic control means, the braking pressure is necessary for the behavior control. There is a risk that the braking pressure will become excessively high.

According to the above-mentioned structure of claim 2, claim 1
In the above configuration, when the pressure increase by the hydraulic pressure control means is started in the situation where the oil pressure from the master cylinder is being supplied to the wheel cylinders, the change of the pressure increase time by the pressure increase time changing means is prohibited. Therefore, it is possible to reliably prevent the braking pressure from becoming excessive at the start of the behavior control.

[0013]

Embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

FIG. 1 is a schematic configuration diagram showing a vehicle braking device to which a behavior control device according to the present invention is applied and an electric control device thereof.

In FIG. 1, the braking device 10 has a master cylinder 14 for pumping brake oil from the first and second ports in response to the driver's depression of the brake pedal 12, and the first port Is connected to the brake hydraulic pressure control devices 18 and 20 for the left and right front wheels by the brake hydraulic pressure control conduit 16 for the front wheels, and the second port is connected by the brake hydraulic pressure control conduit 24 for the rear wheels having a proportional valve 22 in the middle. Brake hydraulic control device 2
6 and 28. Further, the braking device 10 pumps the brake oil stored in the reservoir 30 and supplies it as high-pressure oil to the high-pressure conduit 32.
have. The high-pressure conduit 32 is connected to each brake hydraulic pressure control device 18, 20, 26, 28, and an accumulator 36 is connected in the middle thereof.

Each brake hydraulic control device 18, 20, 2
6 and 28 are wheel cylinders 38FL, 38FR, 38RL, and 38RR that control the braking force for the corresponding wheels.
And 3 port / 2 position switching type electromagnetic control valve 40FL,
40FR, 40RL, 40RR and normally open electromagnetic on-off valves 44FL, 44FR, 44RL, 44RR provided between the low pressure conduit 42 and the high pressure conduit 32 connected to the reservoir 30 and normally closed electromagnetic Open / close valve 46FL, 46FR, 46RL, 46
RR and. Open / close valves 44FL, 44FR, 4 respectively
4RL, 44RR and on-off valves 46FL, 46FR, 46RL, 46RR
The high pressure conduit 32 between and is a connecting conduit 48FL, 48FR, 48
Control valves 40FL, 40FR, 40RL, 40 by RL, 48RR
Connected to RR.

The control valves 40FL and 40FR are respectively the brake hydraulic control conduit 16 for the front wheels and the wheel cylinder 38FL.
And 38FR are connected for communication and the wheel cylinder 38FL
, 38FR and the connecting conduits 48FL and 48FR in the first position shown in the figure, and the brake hydraulic control conduit 16 and the wheel cylinders 38FL and 38FR in communication and the wheel cylinders 38FL and 38FR and the connecting conduit 48FL.
And 48FR are switched to a second position where they are connected for communication. Similarly, 40RL and 40RR are the brake hydraulic pressure control conduit 24 for the rear wheels and the wheel cylinder 3 respectively.
8RL and 38RR are communicatively connected and the wheel cylinder 3
8RL and 38RR and connecting conduits 48RL and 48RR, the first position shown in the figure, and the brake hydraulic pressure control conduit 2
4 and the wheel cylinders 38RL and 38RR are disconnected from each other, and the wheel cylinders 38RL and 38RR are connected to the connecting conduit 4.
8RL and 48RR are switched to a second position where they are connected for communication.

In the situation where the control valves 40FL, 40FR, 40RL, 40RR are in the second position, the on-off valves 44FL, 44FR, 4
4RL, 44RR and on-off valves 46FL, 46FR, 46RL, 46
When the RR is controlled to the illustrated state, the wheel cylinder 38
FL, 38FR, 38RL, 38RR are control valves 40FL, 40FR,
40RL, 40RR and connecting conduits 48FL, 48FR, 48RL,
It is communicatively connected to the high-pressure conduit 32 via 48RR, which increases the pressure in the wheel cylinder. Conversely, when the control valve is in the second position, the on-off valves 44FL, 44FR,
44RL and 44RR are closed and open / close valves 46FL, 46FR and 46
When RL and 46RR are opened, the wheel cylinder is connected in communication with the low-pressure conduit 42 via the control valve and the connecting conduit, which reduces the pressure in the wheel cylinder. Further, when the control valve is in the second position, the on-off valves 44FL, 4FL
4FR, 44RL, 44RR and on-off valves 46FL, 46FR, 46
When RL and 46RR are closed, the wheel cylinder is shut off from both the high-pressure conduit 32 and the low-pressure conduit 42, so that the pressure in the wheel cylinder is maintained as it is.

Thus, the braking device 10 includes the control valve 40FL,
When 40FR, 40RL, 40RR are in the first position, the wheel cylinders 38FL, 38FR, 38RL, 38RR generate a braking force according to the amount of depression of the brake pedal 12 by the driver, and the control valves 40FL, 40FR, 40RL, 40RR are generated.
When any of the RRs is in the second position, the on-off valves 44FL, 44FR, 44RL, 44RR and the on-off valve 46FL of the corresponding wheel are
By controlling opening / closing of 46FR, 46RL, and 46RR, the braking force of the wheel can be controlled regardless of the depression amount of the brake pedal 12 and the braking force of other wheels.

Control valves 40FL, 40FR, 40RL, 40RR,
Open / close valves 44FL, 44FR, 44RL, 44RR and open / close valve 46
FL, 46FR, 46RL, and 46RR are controlled by the electric controller 50 as will be described later in detail. The electric control device 50 comprises a microcomputer 52 and a drive circuit 54, which is not shown in detail in FIG. 1, but is, for example, a central processing unit (CPU).
, A read only memory (ROM), a random access memory (RAM), and an input / output port device, which may be connected to each other by a bidirectional common bus.

In the input / output port device of the microcomputer 52, a signal indicating the vehicle speed V from the vehicle speed sensor 56, a signal indicating the lateral acceleration Gy of the vehicle body from the lateral acceleration sensor 58 provided substantially at the center of gravity of the vehicle body, and a yaw rate sensor 60. Signal indicating the yaw rate γ of the vehicle body, the brake switch (B
S) 62, a signal indicating whether the switch is in the ON state or not, and wheel speed sensors 64FL to 64RR use wheel speeds (peripheral speeds) VFL, VFR, VRL, V of the left and right front wheels and the left and right rear wheels, respectively.
A signal indicating RR is input. The lateral acceleration sensor 58 and the like are adapted to detect lateral acceleration and the like with the left turning direction of the vehicle being positive.

Further, the ROM of the microcomputer 52 stores various control flows and maps as described later, and the CPU performs various calculations as described later based on the parameters detected by the various sensors described above to execute the vehicle operation. The spin value SV for determining the turning behavior is obtained, the turning behavior of the vehicle is estimated based on the spin value, and the control amount for stabilizing the turning behavior of the vehicle is calculated.
Based on the calculation result, the braking force of the left front wheel or the right front wheel is controlled to stabilize the turning behavior of the vehicle.

Next, the turning behavior control of the vehicle according to the illustrated embodiment will be described with reference to the flow charts shown in FIGS. The control according to the flowcharts shown in FIGS. 2 and 3 is started by closing an ignition switch (not shown) and is repeatedly executed at predetermined time intervals.

First, in step 10 of the turning behavior determination routine shown in FIG. 2, a signal indicating the vehicle speed V detected by the vehicle speed sensor 56 is read, and step 20 is executed.
Is the product V of the lateral acceleration Gy, the vehicle speed V, and the yaw rate γ.
The deviation of lateral acceleration, that is, the lateral slip acceleration Vyd of the vehicle is calculated as the deviation Gy-V * γ from * γ, and the lateral slip velocity Vy of the vehicle body is calculated in step 30 by integrating the lateral acceleration deviation Vyd. To be done. In step 40, the slip angle β of the vehicle body is defined as the ratio Vy / Vx of the vehicle side slip velocity Vy to the vehicle longitudinal velocity Vx (= vehicle speed V).
Is calculated, and in step 50, the deviation V of the lateral acceleration calculated in step 20 with A and B as positive constants is calculated.
The spin value SV is calculated according to the following equation 1 based on yd and the slip angle β of the vehicle body calculated in step 40.

[Formula 1] SV = A * Vyd + B * β

The calculation of the spin value SV itself does not form the subject matter of the present invention, and the spin value may be calculated in any form as long as it is calculated as a state quantity corresponding to the spin state of the vehicle. Slip angle β
Alternatively, it may be calculated as a linear sum of the slip angular velocity βd of the vehicle body.

In step 60, when the spin value SV is positive, the right front wheel is spun so that the control wheel, that is, the wheel whose braking force is to be controlled according to the spin value, is specified as the turning outer wheel on the front wheel side. When the value is negative, the left front wheel is specified. In step 70, the target slip ratio Rs of the left front wheel or the right front wheel is calculated from the map corresponding to the graph shown in FIG. 4 based on the absolute value of the spin value SV, and in step 80 the target slip ratio Rs. Is 0, that is, whether or not the turning behavior of the vehicle is stable, and when a positive determination is made, at step 85, the front wheel side control valves 40FL, 40FR are set to the first position. The braking force of each wheel is controlled by the master cylinder pressure according to the depression amount of the brake pedal 12 by resetting to one position. If a negative determination is made in step 80, the target wheel speed Vwt is calculated in step 90 by using Vin as the wheel speed of the turning inner wheel on the front wheel side in accordance with the following equation 2.

## EQU2 ## Vwt = (1-Rs) * Vin

In step 100 of the braking pressure control routine shown in FIG. 3, it is determined whether or not the turning behavior control of the vehicle is started, that is, a positive determination is made in step 80 of the previous cycle. Further, it is judged whether or not the negative judgment is made in step 80 of the present cycle, and step 10
If the affirmative determination is made at 0, it is determined at step 110 whether the brake switch 62 is in the on state, that is, whether the master cylinder pressure is being supplied to the wheel cylinders. Is done. When a negative determination is made in step 110, step 12
Flag F indicating that the turning behavior control is started at 0.
When fa is set to 1 and the timer count value Cfa
Is reset to 0, and in step 130, the rapid pressure increase time Tfa is calculated from the map corresponding to the graph shown in FIG. 5 based on the absolute value of the lateral acceleration Gy of the vehicle body.

At step 140, it is judged if the flag Ffa is 1 or not, that is, if it is in the rapid pressure increase mode at the start of the turning behavior. If a positive judgment is made, step 150 is executed. In this case, the count value Cfa of the timer is Δ
It is counted up by incrementing Cfa, and in step 160 it is determined whether or not the count value Cfa of the timer exceeds the rapid pressure increase time Tfa calculated in step 130. When a positive determination is made in step 160, it is determined in step 170 whether or not the turning behavior control is being performed. When a positive determination is made, the flag Ffa is reset to 0 in step 180. If a negative determination is made in step 140, 160, or 170, the process directly proceeds to step 190.

In step 190, it is judged whether or not the flag Ffa is 1, and when a positive judgment is made, in step 200, the duty ratio of the drive current to the opening / closing valve of the outer turning wheel on the front wheel side is determined. Dr is set to a maximum value Drmax such as 100%, and when a negative determination is made, the duty ratio Dr is set in step 210 according to the following expression 3. In the following expression 3, Vw is the wheel speed of the front outer turning wheel, Vwt is the target wheel speed calculated in step 90, and Kp and Kd are proportional in the wheel speed feedback control. The proportional constant of the term and the derivative term.

## EQU3 ## Dr = Kp * (Vw-Vwt) + Kd * d (Vw
-Vwt) / dt

In step 220, a control signal is output to the control valve 40FL or 40FR of the outer turning wheel on the front wheel side so that the control valve is set to the second position and the turning operation on the front wheel side is also performed. Duty ratio D calculated in step 200 or 210 for the outer ring on-off valve
The output of the control signal corresponding to r controls the supply / discharge of the accumulator pressure to / from the wheel cylinder 38FL or 38FR of the turning outer wheel, thereby controlling the braking pressure of the turning outer wheel.

In this case, when the duty ratio Dr calculated in step 220 is a value between the negative reference value and the positive reference value, the open / close valve upstream of the turning outer wheel is switched to the second position. And the downstream opening / closing valve is held at the first position, the pressure in the corresponding wheel cylinder is maintained, and when the duty ratio is equal to or greater than the positive reference value, the turning outer wheel is opened / closed on the upstream side and the downstream side. By controlling the valve to the position shown in FIG. 1, the pressure in the wheel cylinder is increased by supplying the accumulator pressure to the corresponding wheel cylinder, and the duty ratio is equal to or less than the negative reference value. Occasionally, the open / close valves on the upstream and downstream sides of the turning outer wheel are switched and set to the second position, so that the brake oil in the corresponding wheel cylinder is discharged to the low pressure conduit 42. It is, thereby the pressure within the wheel cylinder is reduced.

Thus, in the illustrated embodiment, step 1
In the turning behavior determination routine from 0 to step 80, the target slip rate Rs of the outer turning wheel on the front wheel side is calculated based on the spin value SV, and it is determined whether or not the turning behavior of the vehicle is stable based on the target slip rate. Then, in step 100 of the braking pressure control routine, it is determined whether or not the turning behavior control is started.

As shown in FIG. 6, when the turning behavior of the vehicle becomes unstable at time t ₁ , step 8
If a negative determination is made at 0 and an affirmative determination is made at step 100, a negative determination is made at step 110, and the larger the absolute value of the lateral acceleration Gy of the vehicle body is at step 130, That is, the rapid pressure increase time Tfa is calculated so that it becomes longer as the magnitude of the lateral force acting on the wheel increases, and steps 140 to 200 and step 220 are executed to start increasing the pressure in the wheel cylinder.

If the amount of brake oil exceeds the dead zone at time t ₂ , the wheel cylinder internal pressure (braking pressure) rises from this time. When surge pressure boosting period Tfa At a time t ₃ has elapsed, it is performed positive determination At a step 160, the flag At a step 180 Ffa
Is reset to 0, a negative determination is made in step 190, and the rapid increase in the wheel cylinder pressure is completed.
At this point, the braking pressure is at a value sufficient to properly start the turning behavior, and thereafter, steps 100, 1
Since a negative determination is made in 40190, the braking pressure of the outer turning wheel is controlled by the wheel speed feedback in step 210, and the braking force of the outer turning wheel on the front wheel side and the braking force of the inner turning wheel are controlled according to the spin value SV. The turning behavior of the vehicle is controlled by the anti-spin moment due to the difference between

FIG. 8 shows an example of changes in the output pulse and the braking pressure when the sudden pressure increase time Tfa at the start of the behavior control is set to a constant value. When the lateral force acting is small and the influence of knockback is small, the braking pressure can be set to a relatively high value within the rapid pressure increase time Tfa as shown by the solid line in FIG. When the lateral force acting on is large and the influence of knockback is great, the braking pressure cannot be increased to a sufficiently high value within the rapid pressure increase time as shown by the phantom line in FIG. Therefore, the turning behavior of the vehicle cannot be optimally executed.

On the other hand, according to the illustrated embodiment, the sudden pressure increase time Tfa is optimally set according to the lateral force acting on the wheel as described above, so that the behavior control is actually started. Since the braking pressure is always controlled to a value sufficient and necessary for behavior control, the turning behavior can be optimally controlled without a response delay, regardless of the magnitude of the lateral force acting on the wheels.

Also according to the illustrated embodiment, step 10
If the affirmative determination is made at 0, it is determined at step 110 whether or not the brake switch 62 is in the on state, and thus it is determined whether or not the mass cylinder pressure is supplied to the wheel cylinders. Is determined,
When a positive determination is made, steps 120 and 130
Is not executed and the process proceeds to step 140.

FIG. 7 shows an example of changes in the output pulse and the braking pressure when the brake switch is turned on before the turning behavior of the vehicle becomes unstable. At a 7, a brake switch 62 is turned on At a point-to, braking pressure is successively raised after a period to ~to 'corresponding to the dead zone, the turning of the vehicle Te further At a time t ₁ If the behavior becomes unstable, the braking pressure has already risen to a value sufficient to start the turning behavior at time t1. According to the illustrated embodiment, in such a situation, an affirmative determination is made in step 110, and steps 140 and subsequent steps are executed without executing steps 120 and 130, so at time t _1. It is possible to reliably prevent an excessive increase in the wheel cylinder pressure due to the pressure increase of the wheel cylinder pressure by the rapid pressure increase time Tfa.

In the illustrated embodiment, step 110
If an affirmative decision is made in step 1
In step 40, steps 140 to 220 are executed without the sudden increase in the wheel cylinder pressure. However, when a positive determination is made in step 110, the rapid increase time Tfa is a constant value. Set to Tfao,
After the flag Ffa is set to 1 and the count value Cfa of the timer is reset to 0, the process proceeds to step 140,
As a result, when the brake switch 62 is turned on before the turning behavior control is started, the pressure in the wheel cylinder is increased at a constant rapid pressure increase time Tfao regardless of the magnitude of the lateral force acting on the wheel. May be configured.

In the illustrated embodiment, the turning behavior of the vehicle becomes unstable from the time when the brake switch 62 is turned on to the time when the affirmative determination is made in step 100. Regardless, when a positive determination is made in step 100, steps 120 and 130
Is not executed, but the braking pressure may reach a value sufficient to execute the turning behavior control between the time when the brake switch is turned on and the time when the vehicle behavior becomes unstable. Step 11 to make sure
If the affirmative determination is made at 0, it is determined whether or not a predetermined time has elapsed from the time when the brake switch is turned on, and it is configured to proceed to step 140 only when the affirmative determination is made. Good.

Further, in the illustrated embodiment, the magnitude of the lateral force acting on the wheel is estimated by the absolute value of the lateral acceleration Gy of the vehicle body, and the rapid pressure increase time Tfa is large in the absolute value of the lateral acceleration Gy of the vehicle body. The correction coefficient K1 based on the slip angle β of the vehicle body and the correction coefficient K2 based on the actual steering angle of the turning outer wheel on the front wheel side are respectively calculated as the slip angle β and the steering angle θ of the vehicle body. Is calculated as a parameter, and a rapid pressure increase time Tfa is calculated from a map similar to that of FIG. 5 with K1 · K2 · | Gy | as the horizontal axis, whereby the rapid pressure increase time is applied to the front outer wheel on the turning side. It may be configured to be calculated more accurately according to the magnitude of the actual lateral force acting.

Although the present invention has been described above in detail with reference to specific embodiments, the present invention is not limited to the embodiments described above, and various other embodiments are also possible within the scope of the present invention. It will be apparent to those skilled in the art that

For example, in the above embodiment, when the turning behavior of the vehicle becomes unstable, the braking force of the turning outer wheel on the front wheel side is controlled according to the spin value SV, and the braking force of the turning outer wheel on the front wheel side is controlled. Although the spin is reduced by the anti-spin moment due to the difference between the braking force of the turning inner wheel and the braking force of the turning inner wheel, the braking force of the turning outer wheel on both the front wheel side and the rear wheel side may be controlled.

In the above embodiment, the target wheel speed V
The wt is calculated according to the equation 2 using the wheel speed Vin of the turning inner wheel on the front wheel side as a reference value, but the target vehicle speed is the vehicle speed V
It may be configured to be calculated on the basis of.

Further, in the above-described embodiment, the hydraulic pressure supplied to each wheel cylinder is the hydraulic pressure from the master cylinder 14 or the hydraulic pressure accumulated in the accumulator 36, but the behavior control of the present invention uses the master cylinder pressure. It may be applied to a vehicle in which an ABS (anti-lock brake system) in which the wheel cylinder pressure is increased as necessary by a corresponding regulator pressure is incorporated.

[0046]

As is apparent from the above description, according to the structure of claim 1 of the present invention, the lateral force acting on the wheel is detected or estimated, and the lateral force at the start of pressure increase by the hydraulic control means. Is larger, that is, the larger the dead zone area of the brake oil amount-actual braking pressure characteristic is, the longer the pressure increasing time is changed by the pressure increasing time changing means by the hydraulic pressure controlling means. The pressure in the wheel cylinder is surely sharply increased so that the amount of brake oil exceeds the dead zone region, whereby it is possible to surely prevent the responsiveness of the behavior control from being deteriorated due to knockback.

According to the second aspect of the present invention, when the pressure increase by the hydraulic pressure control means is started in the situation where the oil pressure from the master cylinder is being supplied to the wheel cylinders, the pressure increase by the pressure increase time changing means is performed. Since the change of time is prohibited, it is possible to reliably prevent the braking pressure from becoming excessive at the start of the behavior control, and to optimally control the behavior of the vehicle.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing a vehicle braking device to which a behavior control device according to the present invention is applied and an electric control device thereof.

FIG. 2 is a flowchart showing a behavior determination routine of turning behavior control by an embodiment of the behavior control device according to the present invention.

FIG. 3 is a flowchart showing a braking pressure control routine for turning behavior control according to an embodiment of the behavior control device of the present invention.

FIG. 4 is a graph showing the relationship between the absolute value of the spin value SV and the target slip ratio Rs.

FIG. 5 is a graph showing a relationship between an absolute value of lateral acceleration GY and a rapid pressure increase time Tfa.

FIG. 6 is a time chart showing an example of changes in output pulse and braking pressure when the brake switch is in the off state at the start of behavior control in the illustrated embodiment.

FIG. 7 is a time chart showing an example of changes in output pulse and braking pressure when the brake switch is in the ON state at the start of behavior control in the illustrated embodiment.

FIG. 8 is a time chart showing an example of changes in the output pulse and the braking pressure when the brake switch is in the off state at the start of the behavior control in the conventional behavior control device.

FIG. 9 is a graph showing the relationship between the amount of brake oil and the actual braking pressure.

[Explanation of symbols]

 10 ... Braking device 14 ... Master cylinder 18, 20, 26, 28 ... Brake hydraulic pressure control device 34 ... Oil pump 38FL, 38FR, 38RL, 38RR ... Wheel cylinder 40FL, 40FR, 40RL, 40RR ... Control valve 44FL, 44FR, 44RL, 44RR ... Open / close valve 46FL, 46FR, 46RL, 46RR ... Open / close valve 50 ... Electric control device 56 ... Vehicle speed sensor 58 ... Lateral acceleration sensor 60 ... Yaw rate sensor 62 ... Brake switch

Claims (2)

[Claims] 1. A master cylinder, a hydraulic pressure generation source, a wheel cylinder provided for each wheel, means for detecting a running state of a vehicle, and when the detected running state is unstable, depending on the running state. A lateral force acting on the wheel in a vehicle behavior control device having hydraulic control means for controlling supply and discharge of high hydraulic pressure from the hydraulic pressure generation source to the wheel cylinder to increase and decrease the hydraulic pressure in the wheel cylinder. And a pressure increasing time changing means for changing the pressure increasing time such that the pressure increasing time by the hydraulic pressure controlling means becomes longer as the lateral force at the pressure increasing start by the hydraulic pressure controlling means becomes larger. A vehicle behavior control device comprising: 2. The vehicle behavior control device according to claim 1, wherein when the hydraulic pressure is started by the hydraulic pressure control means while the hydraulic pressure from the master cylinder is being supplied to the wheel cylinder, A vehicle behavior control device comprising means for prohibiting a change in the pressure increase time by the pressure increase time changing means.