JP2917039B2 - Vehicle slip control device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a vehicle slip control device that controls the slip of a drive wheel in traction control or anti-skid control.

(Prior Art) Conventionally, wheel slip control such as traction control and anti-skid control has been known.

Traction control detects the slip ratio of the drive wheels and controls the engine output and braking force in order to prevent the drive wheels from slipping due to excessive drive torque during acceleration or the like, thereby reducing the acceleration. The slip ratio of the drive wheels is controlled to be a predetermined target slip ratio by decreasing or increasing the braking force.

In addition, anti-skid control detects the slip ratio of each wheel and controls (decreases) the braking force in order to prevent the wheels from being locked due to excessive braking force during braking and to reduce the braking performance. Thus, the slip rate of the wheel is controlled to a predetermined target slip rate.

By the way, in the traction control, when the traveling road surface is a rough road, that is, a road surface with a lot of unevenness, it is conceivable to increase the target slip ratio as compared with a case of a good road in order to prevent a decrease in acceleration.

That is, when the vehicle is on a rough road, the wheel speed changes greatly due to the unevenness of the road surface, and the slip ratio detected based on the wheel speed also changes greatly. As a result, the traction control is not actually required. Regardless, the traction control is often performed when the slip ratio exceeds the target slip ratio, and a situation occurs in which the driving torque is reduced and the acceleration is reduced. Therefore, in the case of a rough road, it is conceivable to set a high target slip ratio and make it difficult to perform traction control, thereby preventing a reduction in driving torque and, consequently, a reduction in acceleration.

Also in anti-skid control, it is conceivable to increase the target slip ratio as compared to a good road in order to enhance braking performance on a bad road.

That is, in the case of a rough road, the braking performance is improved by locking the wheels and hooking the wheels on unevenness of the road surface. Therefore, in the case of a rough road, it is conceivable that the target slip ratio is set to a high value and the anti-skid control is hardly performed, so that the wheels tend to lock and the braking performance is improved.

In order to perform the above-described rough road correction, that is, to correct the content of the slip control such as increasing the target slip ratio in the case of a rough road, it is necessary to determine whether or not the traveling road surface is a rough road. However, as an apparatus for performing such a rough road determination, for example, an apparatus described in Japanese Patent Application Laid-Open No. 64-29636 is known.

(Problems to be Solved by the Invention) However, it is not very preferable to perform the rough road correction for uniformly increasing the target slip ratio with respect to the drive wheels in the case of a rough road.

That is, whether or not the drive wheels should be corrected for a bad road may not only depend on whether the road is bad, but also vary depending on the running state of the vehicle (steering state, vehicle speed, accelerator opening, running mode, etc.). However, depending on the traveling state, it may be better not to perform the rough road correction.

Also, in the case of performing a rough road correction, what kind of content of the rough road correction is optimal to perform, for example, how optimally the target slip ratio is optimally large depends on the traveling state, Therefore, if the content of the rough road correction is fixed, it is not possible to realize the optimum rough road correction according to various running conditions.

SUMMARY OF THE INVENTION An object of the present invention is to provide a vehicle slip control device capable of always performing appropriate rough road correction in slip control in view of the above circumstances.

(Means for Solving the Problems) In order to achieve the above object, a vehicle slip control device according to the present invention has a slip control means for controlling a slip of a drive wheel and a traveling road surface. Road surface determining means for determining whether or not the road is a rough road; rough road correcting means for increasing the control target slip ratio in the slip control means when receiving an output of the road surface determining means; Steering state detection means for detecting a state, and rough road correction control means for prohibiting rough road correction when the steering state is larger than a predetermined value based on the steering state detected by the steering state detection means. It is characterized by having.

The rough road correction for increasing the target slip ratio is not limited to the correction for increasing the target slip ratio in a strict sense, but may be substantially the same as that, that is, a correction in a direction in which control is hardly performed. Anything is fine. For example, when a control start threshold value is provided, the threshold value may be increased, or the control amount may be reduced.

The above-mentioned slip ratio may be any value as long as it is a numerical value representing the slip state of the wheel, and is not limited to a specific value.

The running state of the vehicle means a steering state such as a steering angle and a yaw rate, a vehicle speed, an accelerator opening, a running mode (a traction control mode) such as sports and normal, and the like.

Controlling the rough road correction means controlling whether or not to perform the rough road correction and controlling the content of the rough road correction, for example, how much the target slip ratio is increased.

Specific examples of the rough road correction control based on the running state include the following.

(1) As described in claim 1, when the steering state, that is, when the steering angle and the yaw rate are larger than predetermined values, the rough road correction is not performed.

(2) Even when the steering state is equal to or less than the predetermined value, if the vehicle speed is higher than the predetermined value, the rough road correction is not performed.

(3) Even when the steering state is equal to or less than the predetermined value and the vehicle speed is equal to or less than the predetermined value, the bad road correction is not performed when the accelerator opening is equal to or less than the predetermined value.

(4) As described in claim 4, even if the steering state is equal to or less than a predetermined value, the vehicle speed is equal to or less than a predetermined value, and the accelerator opening is larger than the predetermined value, the selected driving mode is a mode other than the acceleration-oriented mode. For example, when in the normal mode, the rough road correction is not performed.

(5) As described in claim 5, when the steering state is equal to or less than a predetermined value, the vehicle speed is equal to or less than a predetermined value, the accelerator opening is larger than the predetermined value, and the selected traveling mode is the acceleration-oriented mode. , Corrects the rough road.

According to a sixth aspect of the present invention, there is provided a slip control device for a vehicle, comprising: a slip control unit configured to control a slip of a drive wheel; and a road surface determination unit configured to determine whether a traveling road surface is a rough road. A rough road correction means for increasing the control target slip ratio in the slip control means when the output of the road surface determination means is used on a rough road; an accelerator opening detection means for detecting an accelerator opening; A rough road correction control unit for prohibiting a rough road correction when the accelerator opening detected by the opening detection unit is smaller than a predetermined value; Control means for controlling the slip, a road surface determining means for determining whether or not the traveling road surface is a rough road, and a target slip for control in the slip control means when the output of the road surface determining means is a rough road. A rough road correction means for increasing the vehicle speed, a vehicle speed detection means for detecting the vehicle speed, and a rough road correction control means for prohibiting the rough road correction when the vehicle speed detected by the vehicle speed detection means is higher than a predetermined value. As described in claim 8, a slip control means for controlling the slip of the drive wheels, a road surface determination means for determining whether or not the traveling road surface is a rough road, and an output of the road surface determination means. When the vehicle is on a rough road, the slip control means increases the control target slip ratio, a rough road correction means, a running mode detecting means for detecting a running mode of the vehicle, and the running mode is accelerated by the running mode detecting means. When the mode is other than the gender-oriented mode, the rough road correction is prohibited.

(Operation) The vehicle slip control device according to claim 1 controls the rough road correction based on the running state, for example, performs or does not perform the rough road correction, or the content of the rough road correction, for example, the target slip. Since the degree of increasing the rate can be changed, it is possible to perform appropriate rough road correction according to the traveling state.

At the same time, it is possible to prevent the posture stability of the vehicle body from lowering when turning on a rough road.

When the rough road is corrected in the traction control as described above, a larger driving torque is transmitted to the tire, and the driving force acting on the road surface of the tire also increases. By the way, there is a limit to the sum of the front-rear force (driving force) and the lateral force (grip force) that the tire takes on the road surface, and when the driving force acting on such a road surface increases, the The grip force acting on the road surface of the tire decreases. Further, when the rough road is corrected in the above-described anti-skid control, the wheels tend to be locked, and when the driving wheels have such a locked tendency, the behavior of the vehicle body tends to change. That is, in any control, when the rough road correction is performed, the posture stability of the vehicle body decreases.

However, when turning on a rough road, the vehicle body tends to change its posture in the lateral direction, and therefore it is desirable to secure sufficient posture stability.

Therefore, in any of the traction control and the anti-skid control, when the steering state is equal to or more than the predetermined value, the rough road is not corrected. The drop can be prevented.

Also in the device according to the second aspect, it is possible to prevent the posture stability of the vehicle body from deteriorating during high-speed running on a rough road.

If the rough road is corrected during high-speed running, the posture stability of the vehicle body is impaired by the rough road correction as described above. However, when the vehicle is traveling on a rough road at high speed, the posture of the vehicle body is likely to change in the lateral direction as in the case of turning on a rough road. Therefore, it is desirable to secure sufficient posture stability.

Therefore, in any of the traction control and the anti-skid control, even when the steering state is equal to or lower than a predetermined value, when the vehicle speed is high, the rough road is not corrected. It is possible to prevent the posture stability from being lowered during high-speed running.

In the device according to the third aspect, it is possible to perform the slip control more in line with the driver's intention.

That is, when the steering state is equal to or less than the predetermined value and the vehicle speed is equal to or less than the predetermined value, there is no particular problem if the acceleration is improved by performing the rough road correction. When the vehicle speed is small, the driver has no intention to accelerate. Therefore, it is a slip control that meets the driver's intention by stopping the correction of the rough road and not improving the acceleration. The device according to claim 4 relates to a case where the accelerator pedal is depressed, and therefore is intended for a slip control device that performs traction control.

Also in the device according to the fourth aspect, it is possible to perform the slip control more suited to the driver's intention.

That is, when the steering state is equal to or lower than the predetermined value, the vehicle speed is equal to or lower than the predetermined value, and the accelerator opening is higher than the predetermined value, there is no particular problem even if the rough road correction is performed to improve the acceleration performance. Even if this is the case, if the selected driving mode is a mode other than acceleration-oriented, the driver has no intention to accelerate. Is satisfied. The device according to the fifth aspect also relates to an accelerator and a traveling mode, and therefore is intended for a slip control device that performs traction control.

In the device according to the fifth aspect, it is possible to preferably perform the rough road correction and improve the acceleration. That is,
In any of the cases described in claim 5, there is no problem due to the correction of the rough road, and the driver is demanding the acceleration. Therefore, in such a case, any problem is caused by performing the correction of the rough road. Thus, desired acceleration can be improved in accordance with the driver's intention without causing the driver's intention. Of course, this device also targets a slip control device that performs traction control.

On the other hand, in the invention described in claim 6, when the accelerator opening is small, rough road correction is prohibited with respect to when the accelerator opening is large, and slip control that matches the driver's will is executed. In the invention described in claim 7, when the vehicle speed is high, the correction of the rough road is prohibited, and it is necessary to secure the posture stabilization. When the mode is a mode other than the gender-oriented mode, the rough road correction is prohibited, and slip control that matches the driver's intention can be executed.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing one embodiment of a slip control device according to the present invention.

As shown in the figure, in the present embodiment, a slip control unit 100 for controlling the slip of the drive wheels, a rough road determination unit 200 for determining whether or not the traveling road surface is a rough road, and an output of the rough road determination unit When the vehicle is on a rough road, the slip control means performs a rough road correction to increase the control target slip ratio, a rough road correction means 300, a running state detecting means 400 for detecting a running state of the vehicle, Rough road correction control means 500 for controlling the rough road correction in the rough road correction means based on the running state detected by the means.

Next, the above embodiment will be described more specifically.
FIG. 2 is a diagram more specifically showing the above-described embodiment. In this embodiment, slip control as traction control is performed on driving wheels, and in this slip control, both engine control and brake control are performed.

In FIG. 2, A is an automobile provided with the slip control device according to the present embodiment. Car A has left and right front wheels 1FL
And 1FR are driven wheels, and left and right rear wheels 1RL and 1RR are driving wheels. That is, the torque generated by the engine 2 mounted on the front of the vehicle body is controlled by the automatic transmission 3 and the propeller shaft.
4, after passing through the differential gear 5, is transmitted to the left rear wheel 1RL via the left drive shaft 6L, and is transmitted to the right rear wheel 1RR via the right drive shaft 6R.

Configuration of Automatic Transmission The automatic transmission 3 includes a torque converter 11 and a multi-stage transmission gear mechanism 12. The shift is performed by changing the combination of the excitation and the demagnetization of the plurality of solenoids 13a incorporated in the hydraulic circuit of the transmission gear mechanism 12. Further, the torque converter 11 has a hydraulically operated lock-up clutch 11A. By switching between excitation and demagnetization of a solenoid 13b incorporated in a hydraulic circuit of the clutch, engagement and engagement of the lock-up clutch 11A are performed. Release is performed.

The solenoids 13a and 13b are controlled by a control unit UAT for an automatic transmission. This control unit UAT
As is known, the shift characteristic and the lock-up characteristic are stored in advance, and the shift control and the lock-up control are performed based on these characteristics. For this control, the control unit UA
T is a main throttle opening signal from a main throttle opening sensor 61 that detects the opening of the main throttle valve 43 described below, and a sub throttle opening sensor 62 that detects the opening of the sub throttle valve 45. , And a vehicle speed signal (in the embodiment, a rotation speed signal of the propeller shaft 4) from a vehicle speed sensor 63 for detecting the vehicle speed.

Configuration of Brake Fluid Pressure Adjusting Mechanism Each wheel 1FR-1RR is provided with a brake 21FR-21RR. Brake fluid pressure is supplied to calipers (brake cylinders) 22FR to 22RR of the brakes 21FR to 21RR via pipes 23FR to 23RR.

The structure for supplying the brake fluid pressure to each of the brakes 21FR to 21RR is as follows. First, the depression force of the brake pedal 25 is boosted by a booster 26 using a hydraulic booster, and transmitted to a tandem-type master cylinder 27. The hydraulic pressure transmitted to the master cylinder 27 is applied to the left front wheel brake 21FL via a brake pipe 23FL connected to the first discharge port 27a of the master cylinder 27.
Is transmitted to the right front wheel brake 21FR via the brake pipe 23FR connected to the second discharge port 27b of the master cylinder 27.

Hydraulic fluid pressure from a pump 29 is supplied to the booster 26 via a pipe 28, and excess hydraulic fluid is returned to a reservoir tank 31 via a return pipe 30. A branch pipe 28a branches from the pipe 28, and the branch pipe 28a has an electromagnetic open / close type 32.
Is connected. A pipe 33 is branched from the booster 26, and the pipe 33 is connected to an electromagnetic on-off valve 34 and a one-way valve 35 arranged in parallel with the on-off valve 34.

The branch pipe 28a and the pipe 33 are joined at a junction a, and the brake pipes 23RL and 23R for the left and right rear wheels are connected to the junction a.
R is connected. Electromagnetic on-off valves 36A, 37A are connected to the pipes 23RL, 23RR, respectively, and electromagnetic on-off valves 36B, 37B are connected to relief passages 38L, 38R connected downstream of the valves 36A, 37A, respectively. I have.

Each of the valves 32, 34, 36A, 37A, 36B, and 37B described above is controlled by a traction control control unit UTR. That is, when the slip control as the brake control is not performed, the valve 32 is closed, the valve is opened, and the valve
B and 37B are closed, and valves 36A and 37A are opened. Thus, when the brake pedal 25 is depressed, the front wheel brakes 21FR, 21F
The brake fluid pressure is supplied to L via the master cylinder 27. In addition, the working hydraulic pressure of the booster 26 is supplied to the rear wheel brakes 21RR and 21RL via a pipe 33 as brake hydraulic pressure.

As will be described later, when the slip ratio of the rear wheels 1RR and 1RL as drive wheels to the road surface is increased and slip control as brake control is performed, the valve 34 is closed and the valve 32 is opened. Then, by the duty control of the valves 36A, 36B, 37A, 37B, the holding of the brake fluid pressure, the pressure increase and the pressure decrease are performed. More specifically, assuming that the valve 32 is closed, when the valves 36A, 36B, 37A, 37B are closed, the brake fluid pressure is maintained, the valves 36A, 37A are opened, and the valves 36B, 37B are opened. When is closed, the pressure rises, valves 36A and 37A close, and valves 36B and 3
When 7B is open, the voltage drops. The brake fluid pressure passing through the branch pipe 28a is prevented from acting as a reaction force on the brake pedal 25 by the action of the one-way valve 35.

When the brake pedal 25 is depressed during such slip control by the brake control, the hydraulic fluid pressure of the booster 26 corresponding to the depression is applied as brake fluid pressure via the one-way valve 35 to the rear wheel. Brakes 21RR and 21RL are supplied.

Configuration of the engine generated torque adjustment mechanism The control unit UTR for traction control is the drive wheel 1R
In order to perform the slip control by reducing the applied torque to L, 1RR, the brake control by applying the brake to the drive wheels 1RL, 1RR is performed, and the engine control by reducing the generated torque of the engine 2 is also performed. Therefore, a main throttle valve 43 connected to an accelerator pedal 42 and an actuator for adjusting the throttle opening are provided in the intake passage 41 of the engine.
A sub-throttle valve 45 connected to 44 is provided, and the sub-throttle valve 45 is controlled by the control unit UTR for traction control via the actuator 44.

Configuration of Control Unit The traction control control unit UTR performs brake control and engine control by controlling the throttle opening adjustment actuator 44 during slip control. The control unit UTR receives signals from the wheel speed sensors 64 to 67 for detecting each wheel speed, a main throttle opening signal from the main throttle opening sensor 61, and a sub-throttle signal from the sub-throttle opening sensor 62. Throttle opening signal, vehicle speed signal from vehicle speed sensor 63, accelerator opening signal from accelerator opening sensor 68, yaw rate sensor 69
, A shift position signal from the shift position sensor 70, a steering wheel angle signal from the steering wheel angle sensor 71, and a traveling mode signal from the manually operated traveling mode selection switch 72.

Further, the control unit UTR has an input interface for receiving each signal from each of the above sensors, a CPU, a ROM, and an RA.
M, a microcomputer, an output interface, and a drive circuit for driving the valves 32, 34, 36A, 37A, 36B, 37B and the actuator 44.The ROM stores control programs and various control programs required for traction control. A map and the like are stored, and various memories necessary for executing control are provided in the RAM.

Next, the contents of the slip control by the control unit UTR will be described with reference to FIG.

In FIG. 3, the target slip ratio for engine control of the drive wheel is indicated by SET, and the target slip ratio for brake control of the drive wheel is indicated by SBT. Note that SBT is set to a value larger than SET.

Now, until time point t ₁ before, a large slip on the drive wheels has not occurred, the engine control is not performed, the sub throttle valve 47 is thus Cage Contact fully opened, the throttle opening degree (both the throttle valve 43 Tn corresponds to the main throttle opening TH · M, and it is the accelerator opening (the opening of the accelerator pedal, which corresponds to the opening of the throttle valve having the smaller opening). Therefore, when the accelerator pedal is fully depressed, it is fully opened).

t ₁ time, the slip ratio of the driving wheels, is started slip control by the engine control when a target slip ratio SET for the engine control, the throttle opening Tn by closing the sub-throttle valve 45 by controlling the actuator 44 Is reduced all at once to the lower limit control value SM. Then, after the throttle opening degree Tn is once set to SM, the opening degree TH · S of the sub-throttle valve 45 is feedback-controlled so that the slip ratio of the drive wheels becomes the engine control target slip ratio SET. When the engine control is started in this way, the sub-throttle valve opening TH · S becomes smaller than the main throttle valve opening TH · M, and thus the throttle opening Tn becomes the sub-throttle valve opening TH · S. .

If a sufficient slip rate lowering effect cannot be obtained by the above engine control alone, the slip rate continues to increase,
equal to or greater than the target slip ratio SBT for the brake control in t ₂ time.

When the slip ratio of the driving wheels t ₂ time becomes equal to or higher than the target slip ratio SBT for controlling brake, drive wheel brake 21RR, 21RL
Is supplied to the vehicle, and slip control by both the engine control and the brake control is started. The brake fluid pressure is feedback-controlled such that the slip ratio of the drive wheels becomes the brake control target slip ratio SBT.

t ₃ time, the slip ratio of the driving wheels is less than the target slip ratio SBT for controlling brake, the brake fluid pressure is the pressure reduction, the slip control is terminated by the brake control eventually become the brake fluid pressure is zero. However, the slip control by the engine control is still continued.

The target slip rates SBT and SET may be determined as appropriate. For example, the target slip rates SBT and SET are determined by the control unit UTR based on the road surface μ, the vehicle speed, the accelerator opening, the steering angle of the steering wheel, the running mode of sports or hardware, and the like. Also, the SM is appropriately determined by the control unit UTR based on, for example, the road surface μ.

The brake control is performed independently on the left and right sides based on, for example, the slip ratios S _L and S _R of the left and right drive wheels. In addition, the engine control is performed by, for example, determining the slip ratio
This is performed based on the larger slip ratio S _E of S _L and S _R. Incidentally, the slip ratio S _L, S _R, in the control unit UTR, based on the wheel speed signals from the wheel speed sensors 63 to 66, is calculated according to the following equation.

VK _L : Rotation speed of left drive wheel VK _R : Rotation speed of right drive wheel LV: Average value of rotation speed of left and right driven wheels Note that the slip ratio is always calculated based on the above formula. It is not necessary, and any value may be used as long as the value substantially indicates the slip control of the wheel. For example, a value obtained by simply subtracting the driven wheel speed from the driven wheel speed may be used.

By the way, as described above, in addition to the slip control means 100 (configured by the control unit UTR) for controlling the slip of the drive wheels, the wheel speed sensors 64 to 67 and the control unit Bad road determination means 200 comprising UTR, bad road correction means 300 comprising the control unit UTR, yaw rate sensor 69 and steering wheel angle sensor 71 as steering state detection means, vehicle speed sensor 63 as vehicle speed detection means, An accelerator opening degree sensor 68 as an accelerator opening degree detecting means, a traveling state detecting means 400 comprising the traveling mode selection switch 72 as a traveling mode detecting means, and a rough road correction control means 500 comprising the control unit UTR are provided. Consisting of

In the slip control device, the control means 100 performs the slip rate control so that the slip rate of the drive wheels becomes the target slip rate set separately as described above, and the rough road determination means 200 It is determined whether or not the traveling road surface is a rough road having irregularities. If the traveling road surface is a rough road, the rough road correction means 300 performs the rough road correction for increasing the target slip ratio and further detects the traveling state. The traveling state is detected by the means 400, and the rough road correction is controlled based on the traveling state.

Bad Road Correction and Bad Road Correction Control in Traction Control Next, an example of a bad road correction and bad road correction control procedure in traction control will be described with reference to the flowchart shown in FIG.

First, in S1, it is determined whether or not the road is bad. This rough road determination may be performed by any method. In this embodiment, the rough road determination means 200 performs the following method.

That is, in the case of a rough road, in consideration of the fact that the wheel acceleration fluctuates due to unevenness of the road surface, for example, the acceleration of the driven wheel is obtained from the rotational speed of the driven wheel, and the acceleration includes the acceleration of the vehicle body. The acceleration of the vehicle body is subtracted from the acceleration by a method, and a temporal change of the subtraction result (this is referred to as a true driven wheel acceleration), that is, a vibration of the true driven wheel acceleration is obtained. Then, as shown in FIG. 5, the number of times that the vibration peak of the true driven wheel acceleration exceeds a predetermined threshold value α given in advance within a predetermined time period (becomes larger than + α and smaller than −α). The number of times is determined, and it is determined whether the number is greater than a predetermined threshold value β. If the number is greater than β, the road is determined to be a bad road. .

If it is not a rough road, the process proceeds to S6 and S7, and the slip control is performed without performing the rough road correction. That is, the target slip ratio STA (SET, SBT in the above embodiment) is set to a normal target slip ratio, and slip control is performed based on the normal target slip ratio. Alternatively, the control start threshold value VSPA is set when performing the slip control, and the slip ratio is set to the VSPA (this is the target slip ratio STA).
When the slip control is started and the slip rate is controlled to reach the target slip rate STA, the control start threshold value VSPA is set to the normal control start threshold value. To perform slip control based on the VSPA.

On the other hand, if it is determined in S1 that the road is rough, it is determined in S2 whether the absolute value of the steering angle (the right steering angle is (+) and the left steering angle is (-)) is greater than 10 °. If it is determined that the angle is larger than 10 °, the process proceeds to S6 and S7 without performing the rough road correction, and the normal slip control is performed.

If the steering angle is 10 ° or less, the vehicle speed becomes 80 in S3.
It is determined whether or not the speed is higher than Km / h. If the speed is higher than 80 km / h, the process proceeds to S6 and S7 without performing the rough road correction.

When the vehicle speed is 80 km / h or less, the accelerator opening is 50% in S4 (0% when the accelerator is fully closed, 10% when the accelerator is fully open).
0%), and if it is smaller than 50%, the process goes to S6 and S7 without performing the rough road correction.

Further, when the accelerator opening is equal to or more than 50%, the process proceeds to S5, and it is determined whether or not the selected traveling mode is the normal mode. In the present embodiment, a sports mode in which acceleration is emphasized and a normal mode in which acceleration is not emphasized are set as the traveling modes. In the case of the normal mode, the process proceeds to S6 and S7 without correcting a rough road.

If the mode is not the normal mode, that is, if the mode is the sports mode, the process proceeds to S8 and S9, and the slip control is performed after performing the rough road correction. In the rough road correction, the target slip rate STA was set to a large slip rate STA ₁ than the normal target slip ratio, or control start threshold greater threshold than the normal control start threshold value VSPA Value VSPA
Set to ₁ and perform slip control based on them.

In the above rough road correction, both the STA and the VSPA may be increased, or one of them may be increased. Also,
If there are STAs and VSPAs for engine control and brake control, both engine control and brake control may be increased, or one of them may be increased. In addition,
FIG. 3 shows an embodiment in which the target slip ratio for brake control is increased by correction of a rough road (SBT → SBT ₁ ).

In short, the above-described control is performed even if the road is rough.
If YES in 2, S3, S4, S5, the rough road correction is prohibited, and
Bad road correction is performed only in the case of O.

With the above control, in the slip control as the traction control, when the steering angle is large or when the vehicle speed is large, the rough road correction is not performed. There is no risk that posture stability will be impaired. Also, when the accelerator does not require acceleration, the accelerator is not opened, and rough road correction is not performed at the time of selecting the normal mode, so that it matches the driver's intention without improving acceleration due to rough road correction. The slip control is performed. Further, when the deterioration of the vehicle body posture stability does not cause any particular problem and the driver seeks acceleration, that is, when the steering mode is small, the steering speed is low, the middle speed is large, the accelerator opening is large, and the normal mode is set, the rough road correction is performed. Is carried out, and appropriate acceleration is improved.

Bad road correction and bad road correction control in anti-skid control Next, bad road correction and bad road correction control in anti-skid control will be described.

In the case of the slip control as the anti-skid control, the only difference is that the brake control of the slip control as the traction control is to appropriately increase the brake fluid pressure, whereas the brake control is to appropriately reduce the brake fluid pressure.
Therefore, a specific example of the device configuration is basically the same as that of the slip control device shown in FIG.
The control unit UTA stores a control program for anti-skid control, various maps, and the like. Therefore, a specific description of the device will be omitted, and a flowchart showing an example of rough road correction and rough road correction control will be described below. This will be described with reference to FIG.

Also in this case, first, in S10, it is determined whether or not the road is rough based on the same rough road determination means 200 as described above.
Proceed to 14, S15, and perform slip control without performing rough road correction. That is, the target slip ratio is set to the normally used target slip ratio of 0.2, and the slip control is performed so that the slip ratio of the drive wheels becomes the target slip ratio.

In the case of a rough road, the process proceeds to S11, where it is determined whether the absolute value of the steering angle is greater than 10 °.
Proceeding to S14 and S15, the slip control is performed without performing the rough road correction.

If the steering angle is less than 10 °, proceed to S12, where it is determined whether the vehicle speed is greater than 80km / h.
4, the process proceeds to S15, and the slip control is performed without performing the rough road correction.

When the vehicle speed is equal to or lower than 80 km / h, the process proceeds to S13 and S15, and the slip control is performed by performing the rough road correction. That is, the target slip ratio is set to 0.3 which is larger than the normally used target slip ratio 0.2, and control is performed so that the slip ratio of the drive wheels becomes the large target slip ratio.

In short, the above-described control is performed in the above S1 even on a rough road.
If the answer is YES in steps S1 and S12, the rough road correction is prohibited, and the rough road correction is performed only in the case of NO.

With the above control, in slip control as anti-skid control, when the steering angle is large or when the vehicle speed is large, rough road correction is not performed. There is no risk that the posture stability will be impaired. In addition, in the case of a small steering angle and a low / medium speed where the reduction of the stability of the vehicle body posture due to the locking of the driving wheels is not a particular problem, the braking performance can be improved by performing the rough road correction.

Note that the wheel slip rate when performing anti-skid control of the drive wheels may be the same as the slip rate used when performing the above-described traction control, or may be different.

(Effects of the Invention) As described in detail above, the slip device for a vehicle according to the present invention is configured to appropriately control the rough road correction based on the traveling state. Bad road correction can be performed.

In particular, by deciding whether or not to perform the rough road correction appropriately based on the steering state, the vehicle speed, the accelerator opening, the traveling mode, and the like, as described above, particularly when turning or when traveling at high speed where the vehicle body posture stability is required. Sometimes, the stability of the posture is not impaired by the rough road correction, and the driver decides whether to require acceleration because it determines whether to perform the rough road correction based on the accelerator opening and the driving mode. Is possible.

[Brief description of the drawings]

FIG. 1 is a block diagram schematically showing an embodiment of the present invention, FIG. 2 is an overall system diagram specifically showing an embodiment of the present invention, and FIG. 3 is slip control as traction control in the embodiment of the present invention. FIG. 4 is a flowchart of traction control in the embodiment of the present invention, FIG. 5 is a diagram illustrating a method for determining a bad road, and FIG. 6 is a flowchart of anti-skid control in the embodiment of the present invention. . 100: slip control means 200: rough road determination means 300: rough road correction means 400: running state detection means 500: rough road correction control means

──────────────────────────────────────────────────続 き Continuation of front page (72) Inventor Toru Onaka 3-1, Shinchi, Fuchu-cho, Aki-gun, Hiroshima Prefecture Inside Mazda Corporation (56) References JP-A-60-107440 (JP, A) JP-A Sho 61-71264 (JP, A) JP-A-60-35648 (JP, A) JP-A-3-21556 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) B60T 8/58

Claims (8)

(57) [Claims] 1. A slip control means for controlling a slip of a drive wheel, a road surface determining means for determining whether or not a traveling road surface is a rough road, Bad road correction means for increasing the control target slip ratio in the slip control means, steering state detection means for detecting the steering state, and a steering state larger than a predetermined value based on the steering state detected by the steering state detection means. And a rough road correction control unit for prohibiting the correction of a rough road when the vehicle slips. 2. The slip control device according to claim 1, wherein the rough road correction control means receives the output of the steering state detection means, and the steering state is equal to or less than a predetermined value and the vehicle speed is higher than the predetermined value. A slip control device for a vehicle, which is configured to prohibit correction of a bad road. 3. The slip control device according to claim 1, further comprising: vehicle speed detecting means for detecting a vehicle speed; and accelerator opening detecting means for detecting an accelerator opening. The vehicle slip control device is configured to prohibit the correction of a rough road when the vehicle speed is equal to or lower than a predetermined value, the vehicle speed is equal to or lower than a predetermined value, and the accelerator opening is equal to or lower than a predetermined value. 4. A slip control device according to claim 1, further comprising a vehicle speed detecting means for detecting a vehicle speed, an accelerator opening detecting means for detecting an accelerator opening, and a running mode detecting means for detecting a running mode of the vehicle. When the steering condition is below, the vehicle speed is below a predetermined value, the accelerator opening is larger than a predetermined value, and the traveling mode is a mode other than the acceleration-oriented mode, the rough road correction control means A vehicle slip control device for which correction is prohibited. 5. The slip control device according to claim 1, further comprising a vehicle speed detecting means for detecting a vehicle speed, an accelerator opening detecting means for detecting an accelerator opening, and a running mode detecting means for detecting a running mode of the vehicle. The above-mentioned rough road correction control means performs a rough road correction when the steering state is below, the vehicle speed is below a predetermined value, the accelerator opening is larger than a predetermined value, and the traveling mode is a mode of the acceleration-oriented mode. And a vehicle slip control device. 6. A slip control means for controlling the slip of the drive wheels, a road surface determining means for determining whether or not the traveling road surface is a rough road, and receiving the output of the road surface determining means when the road surface is rough, Bad road correcting means for increasing the control target slip ratio in the slip control means, accelerator opening detecting means for detecting the accelerator opening, and when the accelerator opening detected by the accelerator opening detecting means is smaller than a predetermined value. A vehicle slip control device comprising: a rough road correction control unit for prohibiting a rough road correction. 7. A slip control means for controlling a slip of a driving wheel, a road surface determining means for determining whether or not a traveling road surface is a rough road, and receiving the output of the road surface determining means, the road surface determining means is provided for determining whether the road surface is rough. Bad road correction means for increasing the control target slip ratio in the slip control means, vehicle speed detection means for detecting the vehicle speed, and bad road prohibition when the vehicle speed detected by the vehicle speed detection means is higher than a predetermined value. A vehicle slip control device, comprising: road correction control means. 8. A slip control means for controlling a slip of a driving wheel, a road surface judging means for judging whether or not a traveling road surface is a rough road, and receiving the output of the road surface judging means, when the road surface is a bad road, Bad road correcting means for increasing the control target slip ratio in the slip control means, running mode detecting means for detecting the running mode of the vehicle, and when the running mode is a mode other than the acceleration-oriented mode by the running mode detecting means. Is a vehicle slip control device for prohibiting rough road correction.