JP2992966B2 - Vehicle slip control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a slip control device for a vehicle, which prevents a drive wheel from slipping too much on a road surface.

[0002]

2. Description of the Related Art Various slip control devices (traction control devices) have been proposed which prevent the driving wheels from slipping on the road surface during acceleration of the vehicle or the like, thereby satisfying acceleration performance and vehicle stability. ing.

[0003] The slip control is performed by reducing the torque applied to the driving wheels. Therefore, the braking control for applying a braking force to the driving wheels and the engine for reducing the generated torque (output) of the engine are performed. Control is performed. In both of the brake control and the engine control, feedback control is generally performed so that the actual slip value of the drive wheels with respect to the road surface becomes a predetermined target value.

Japanese Patent Laid-Open No. 60-128 discloses that slip control is performed by both brake control and engine control.
No. 028 and JP-A-63-166649. Japanese Patent Application Laid-Open No. 60-128028 discloses an engine in which the engine control is started when the difference between the rotational speeds of the left and right drive wheels becomes equal to or greater than a predetermined value. JP-A-63-1
Japanese Patent Application Publication No. 66649 discloses a system in which only the engine control is performed when the slip value of the drive wheel is small, and both the engine control and the brake control are performed when the slip value of the drive wheel is large. Have been.

Further, at the start of the slip control, the applied torque to the drive wheels is reduced at a stroke by temporary feedforward control, and the applied torque reduction amount at this time is set according to the road surface μ. Has also been done. Further, a target value for slip control is changed at the time of turning or the like.

[0006]

The control amount for the slip control is basically determined by a target value, but the control amount determined according to the target value is achieved at any response speed. This, that is, what value the control gain is set to is important in performing the slip control satisfactorily. However, conventionally, the control gain remains fixed at a certain value, and there is a limit in performing the slip control satisfactorily.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a vehicle slip control device capable of setting a control gain of the slip control more appropriately and performing better slip control.

In order to achieve the above object, the present invention has the following configuration as a first configuration. That is, as described in claim 1 of the claims, a torque adjusting means for adjusting the applied torque to the driving wheels, a slip detecting means for detecting a slip value of the driving wheels with respect to the road surface, and the slip detecting means. The detected slip value is the first
And controlling the torque adjusting means so that the detected slip value becomes a predetermined target value when the detected slip value is larger than a second predetermined value smaller than the first predetermined value. When the control amount by the slip control means is large when the detected slip value is smaller than the second predetermined value. And control gain changing means for increasing the control gain in the slip control means as compared to when the control amount is small. To achieve the above object, the present invention has the following configuration as a second configuration. That is,
As described in claim 2 of the claims, torque adjustment means for adjusting the torque applied to the drive wheels, slip detection means for detecting a slip value of the drive wheels with respect to the road surface, and the slip detection means Slip control means for controlling the torque adjusting means so that when the detected slip value is larger than a first predetermined value, the detected slip value becomes a predetermined target value smaller than the first predetermined value;
Control gain changing means for increasing the control gain in the slip control means as the time from when the detected slip value first becomes smaller than the first predetermined value to when the detected slip value becomes the target value is longer. There is a configuration.

In order to achieve the above object, the present invention has the following configuration as a third configuration. That is, as described in claim 3 of the claims, a braking force adjusting means for independently adjusting the braking force on the left and right driving wheels, and a slip detecting means for detecting a slip value of the driving wheels with respect to the road surface. Brake control means for controlling the brake force adjusting means so that when the slip value detected by the slip detection means is larger than a predetermined value, the detected slip value becomes a predetermined target value; and When the control amount of the brake control unit is large at the time when the control by the unit reduces the braking force to the left and right drive wheels, the control gain in the brake control unit is increased as compared with when the control amount is small. And control gain changing means. To achieve the above object, the present invention has the following configuration as a fourth configuration. That is, the first torque adjusting means for adjusting the generated torque of the engine, the second torque adjusting means for adjusting the braking force on the driving wheels, and the road surface of the driving wheels. A slip detecting means for detecting a slip value with respect to the motor, and performing slip control for controlling the first torque adjusting means when the detected slip value detected by the slip detecting means is larger than a first predetermined value. When the slip value is larger than a second predetermined value which is larger than the first predetermined value, a slip control for performing a slip control for controlling the second torque adjusting means together with the first torque adjusting means. Means, if the time from when the detected slip value first becomes larger than the first predetermined value to when it becomes larger than the second predetermined value is long, the time is Compared to Itoki, a configuration equipped with a control gain changing means for the control gain is increased in the slip control unit.

According to the first aspect of the present invention, when the slip control amount at the end of the slip control is large, the slip is likely to occur again. In this case, the control gain of the slip control is increased. By doing so, control responsiveness when a slip occurs again is enhanced, which is preferable for promptly converging the slip.
According to the second aspect of the present invention, the fact that the time from the start of the slip control to the predetermined target value is long means that the re-slip is likely to occur or the slip hardly converges. In this case, it is preferable to increase the control gain to quickly converge the slip.

According to the third aspect of the present invention, the fact that both the left and right driving wheels are slipping means that re-slip is likely to occur or that slip hardly converges. This is preferable in that the control gain is increased to make the slip converge quickly. According to the invention described in claim 4, when the time from the start of the slip control using only the engine to the start of the slip control also using the brake is long, the slip control using the brake is started with a delay. Although it is difficult to quickly make the slip converge, it is preferable to increase the control gain and make the slip converge quickly.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the accompanying drawings. In FIG. 1, 1FL is a left front wheel, 1FR is a right front wheel, 1RL is a left rear wheel, and 1RR is a right rear wheel. The engine 2 is mounted horizontally on the front of the vehicle body.
Torque generated by the clutch 3, the transmission 4, the differential gear 5,
Is transmitted to the left front wheel 1FL via the left drive shaft 6L and to the right front wheel 1FR via the right drive shaft 6R. As described above, the vehicle has the front wheels 1F
L, 1FR are drive wheels, and rear wheels 1RL, 1RR are front wheel drive vehicles that are driven wheels.

[0013] Brakes 7FR to 7R mounted on each wheel
R is a hydraulic disk brake.
Further, a master cylinder 8 as a brake hydraulic pressure generating source is provided.
Is a tandem type having two discharge ports 8a and 8b. A brake pipe 13 extending from one discharge port 8a of the master cylinder 8 is branched into two on the way.
The branch pipe 13F is connected to the left front wheel brake 7FL (a wheel cylinder mounted in the caliper), and the branch pipe 13R is connected to the right rear wheel brake 7RR.
The branch pipe 14 extending from the other discharge port 8b of the master cylinder 8 is also branched into two, the branch pipe 14F is connected to the right front wheel brake 7FR, and the branch pipe 14R is connected to the left rear wheel brake 7RL. It is connected.

Branch pipe 13 for front wheels, that is, for drive wheels
F and 14F are provided with an electromagnetic hydraulic pressure control valve 15L or 1F.
5R is connected, and an electromagnetic on-off valve 16L or 16R is connected to the branch pipes 13R and 14R for the rear wheels. The hydraulic pressure adjusting valves 15L and 15R are provided with a brake 7FL,
The brake fluid pressure supply from the master cylinder 8 to the 7FR and the brake fluid pressure of the brakes 7FL and 7FR
The mode of release to the reservoir tanks 22L and 22R via 1L and 21R is switched. The brake fluid in the reservoir tank 21L is returned to the pipe 13 via a pipe 25L to which a check valve 24L is connected by a pump 23L. Similarly, the brake fluid in the reservoir tank 22R is
By R, it is returned to the pipe 14 via the pipe 25R to which the check valve 24R is connected.

The stepping force on the brake pedal 12 is
The power is transmitted to the master cylinder 8 via a booster, that is, a brake booster 11. The booster 11 is basically the same as a known vacuum booster. However, in the case of slip control, as will be described later, the booster action is performed even if the brake pedal is not depressed. Is performed.

The booster 11 has a case 31 fixed to the vehicle body and the master cylinder 8, and the inside of the case 31 is formed by a diaphragm 32 and a valve body 33 fixed thereto. A chamber 34 and a second chamber 35 are defined. A negative pressure (for example, the negative pressure of the intake air of the engine 2) is always supplied to the first chamber 34. When the brake pedal is not depressed, the second chamber 35 is communicated with the first chamber 34, -The operation of the star 11 is stopped. When the brake pedal 12 is depressed,
Atmospheric pressure is supplied to the second chamber 35, whereby the diaphragm 32 is displaced forward together with the valve body 33 to perform a boosting function.

The switching between the negative pressure supply and the atmospheric pressure supply to the second chamber 35 is basically performed by a valve device provided in the valve body 33. This valve body 33
The portion will be described with reference to FIG.

First, the valve body 33 has a power piston 41 fixed to the diaphragm 32. In a recess 41a formed in the power piston 41, a reaction disk 42 and a base end of an output shaft 43 are provided. Are fitted. This output shaft 43 serves as an input shaft of the master cylinder 8. A valve plunger 45 is mounted in the valve body 33 at the tip of the input shaft 44 connected to the brake pedal 12. Behind the valve plunger 45, a vacuum valve 46 is provided.

The power piston 41 has a pressure introducing passage 50.
The pressure introducing passage 50 is always in communication with a space X formed around the valve plunger 45. This space X is always in communication with the second chamber 35. A valve seat 47 on which the vacuum valve 46 is detached and seated is formed at an opening end of the pressure introducing passage 50 on the space X side. Further, the vacuum valve 46 includes a valve plunger 45.
The seat is also detached from and seated on a valve seat 45a formed at the rear end.

In the above configuration, it is assumed that a negative pressure is introduced into the pressure introducing passage 50. In this state, when the brake pedal 12 is not depressed, the vacuum valve 46 is seated on the valve seat 45a by the urging force of the springs 48 and 49 in the state of FIG. ing. Therefore, the pressure introduction passage 5
The negative pressure from 0 is introduced into the second chamber 35 via the space X, and no boosting action is performed.

When the brake pedal 12 is depressed,
The input shaft 44 and thus the valve plunger 45 are moved forward (to the left in the drawing). During this forward movement, the vacuum valve 46
Is first seated on the valve seat 47 and the space X and the pressure introduction passage 50 are
To the vacuum valve 46 and the valve seat 45
a are separated. When the vacuum valve 46 and the valve seat 45a are separated from each other, the atmospheric pressure from behind the valve body 33 is introduced into the space X, and the second chamber 35 becomes the atmospheric pressure. As a result, the diaphragm 32 is displaced forward together with the valve body 33, and as a result, the output shaft 43 moves forward and a boosting action is performed. The brake reaction force from the master cylinder 8 is transmitted via the reaction disk 42 to the valve plunger 45 and thus to the brake pedal 12.
When the brake pedal 12 is released, the return spring 36 (see FIG. 1) returns to the state shown in FIG. 2 to prepare for the next boosting action.

The above-described parts are the same as those of the known vacuum booster, but in this embodiment, the negative pressure of the first chamber 34 is introduced into the pressure introduction passage 50 for slip control. The state is switched to a state in which atmospheric pressure is introduced. That is, the first chamber 34 and the pressure introduction passage 5
0 is connected via a pipe 37, and a three-way electromagnetic switching valve 38 (see FIG. 1) is connected to the pipe 37. The switching valve 38 connects the pressure introduction passage 50 to the first chamber 34 during demagnetization, and introduces atmospheric pressure into the pressure introduction passage 50 during excitation. When the switching valve 38 is excited and atmospheric pressure is introduced into the pressure introducing passage 50, the space X and hence the second chamber 35
Thus, even if the brake pedal 12 is not depressed, the pressure becomes the atmospheric pressure. As a result, a boosting action is performed to generate a brake hydraulic pressure in the master cylinder 8.

FIG. 3 schematically shows a control system. In FIG. 3, U is a control unit constituted by using a microcomputer.
Signals from sensors or switches S1 to S8 are input. The sensors S1 to S4 detect rotation speeds of the wheels 1FL to 1RR. The switch S5 is an accelerator switch that is turned on when the accelerator pedal 10 is fully closed. Switches S6 and S7 are each
The switch is activated when the key pedal 12 is depressed, for example, one switch is normally open and the other is normally closed. The sensor S8 detects the engine speed. In addition, although output from the control unit U to each device shown in FIG. 3, reference numeral 9 denotes torque adjusting means for adjusting the generated torque of the engine 2. The torque adjusting means 9 adjusts the generated torque by, for example, adjusting the amount of intake air or by combining the number of fuel cut cylinders and the ignition timing.

Next, an outline of the slip control will be described with reference to FIG.
Will be described with reference to FIG. In FIG. 4, the left driving wheel 1
An example is shown where no slip occurs in the FL and a large slip occurs in the right drive wheel 1FR.

Engine Control First, the engine control starts with the left and right front wheels 1FL, 1FR
Are started when the larger one of the slip values becomes equal to or larger than a predetermined start threshold value (t in FIG. 4).
1). The engine control is performed by performing feedback control on the torque adjusting means 9 so that the actual slip value becomes the engine target value (first target value) STE. The engine control is stopped when the accelerator is fully closed, or when the time when the actual slip value has become the control continuation threshold SC (smaller than the first target value) has continued for a predetermined time or more (FIG. 4 from t6 to t7).

Brake Control The brake control is started when all of the following conditions are satisfied. The first start condition is that the engine is being controlled. The second start condition is that the left and right drive wheels 1FL, 1F
That is, the difference between the actual slip values of R is equal to or larger than a predetermined value (t2 in FIG. 4). The third start condition is that the vehicle speed is equal to or lower than a predetermined first vehicle speed V1. The fourth start condition is that a predetermined delay time described later has elapsed.

Prior to the start of the brake control, in consideration of a response delay, the switching valve 38 is started simultaneously with the start of the engine control.
Is excited, the booster 11 is brought into a boosted state, the hydraulic pressure regulating valves 15L and 15R are at the relief position, and the on-off valves 16L and 16R are closed. Then, after the switching valve 38 is excited, when the actual slip value shows a predetermined deceleration (the time until the predetermined deceleration is shown is the delay time, and in FIG. 4, between t2 and t3). , Bra
Key control is started.

The brake control is performed on the left and right driving wheels 1FL, 1F.
By independently controlling the hydraulic pressure regulating valves 15L and 15R in such a manner that the actual slip value of each of R becomes the brake target value (second target value) STB (> STE). (Duty control).

The suspension of the brake control is performed when any one of the following conditions is satisfied. The first stop condition is when engine control is stopped. The second stop condition is when the vehicle speed becomes higher than a predetermined second vehicle speed V2 (V2> V1). The third stop condition is that the control signals for the left and right hydraulic pressure control valves 15L, 15R both indicate a pressure reduction and for a predetermined time (500 msec in the embodiment).
c) This is the time when the continuation is continued (t4 to t5 in FIG. 4).

The fourth stop condition is a left and right brake 7F.
This is when the brake fluid pressures of L and 7FR are both zero. The fifth stop condition is when one of the switches S6 and S7 detects that the brake pedal 12 is depressed (the brake pedal 12 is depressed by the switches S6 and S7). Is detected, the start of the brake control is prohibited).

When the brake control is stopped, the switching valve 38 is operated as long as the engine control is performed, the hydraulic pressure adjusting valves 15L and 15R are in the relief positions, and the on-off valve 1
6L and 16R are closed (the same state as the standby state until the start of the brake control). When the engine control is stopped or the brake pedal 12 is depressed, the switching valve 38 is demagnetized.

Next, a control example of the present invention will be described with reference to flowcharts shown in FIG. 5 and subsequent figures. In the following description, P indicates a step. FIG. 5 shows the overall flow. First, at P1, after the signals from the respective sensors and the like are input, at P2, the rotational speeds WSRL and WSRR of the left and right drive wheels 1FL, 1FR are averaged to obtain The vehicle speed VS is calculated.

At P3, a first target value STE for engine control and a second target value STB for brake control are determined in a known manner (STB> STE). In P4,
The slip value SFL of the left driving wheel 1FL is equal to its rotational speed W.
The vehicle speed VS is calculated by subtracting the vehicle speed VS from the SFL. Similarly, the slip value SFR of the right drive wheel 1FR is calculated by subtracting the vehicle speed VS from the rotation speed WSFR.

In the processing of P5 to P7, the larger of the left and right drive wheel slip values SFL and SFR is set as the engine control slip value SA. In P8, it is determined whether the slip flag is 1 or not. When the slip flag is 1, it means that the slip control is being performed (at least the engine is being controlled). When the determination in P8 is NO, after the start determination of the engine control described later is made in P9, P1
At 0, an end determination described later is made.

If the determination in P8 is YES, after the engine control is performed in P11, in P12,
It is determined whether the brake flag is "1". When the brake flag is "1", it means that the brake control is being performed. If the determination in P12 is NO, a brake start determination, which will be described later, is made in P13.
Move to. If the determination in P12 is YES, P
After the brake control is performed at 14, the program proceeds to P10.

FIG. 6 shows the contents of P9 in FIG. First,
At P21, the actual slip value SA for the engine
Is greater than or equal to a predetermined value indicating a predetermined start threshold value. If the determination in P21 is NO, it means that the slip control is unnecessary, and the program returns to P1 as it is. If the determination in P21 is YES, the slip flag is set to 1 in P22, engine control is started in P23, and preparation for starting brake control is made in P24. Specifically, the preparation in P24 is performed by exciting the switching valve 38 and causing the master cylinder 8 to brake.
The hydraulic pressure is generated, and the hydraulic pressure adjusting valve 15L,
5R to the relief position, and the on-off valves 16L, 16
R is closed.

FIG. 7 shows the contents of P13 in FIG. First, at P31, it is determined whether the vehicle speed VS is equal to or lower than the first vehicle speed V1. If the determination in P31 is YES, the rotational speed difference DNL between the left and right drive wheels 1FL and 1FR is calculated in P32, and then in P33,
It is determined whether or not the difference DNL is equal to or greater than a predetermined value.
If the determination in P33 is YES, in P34,
It is determined whether or not a predetermined delay time has elapsed since the occurrence of the difference (t2 to t3 in FIG. 4). If the determination in P34 is YES, after the brake flag is set to 1 in P35, in P36, the hydraulic pressure adjusting valve 15L,
Brake control by controlling 15R is started. NO in any of the names P31, P33, and P34
In the case of, the process ends.

FIG. 8 shows the contents of P10 in FIG. First, in P41, it is determined whether or not the accelerator is fully closed. If the determination in P41 is YES, P42
After the slip control, that is, both the engine control and the brake control are stopped, the respective flags are reset to 0 in P43.

If the determination in P41 is NO, in P45, it is determined whether or not the actual slip value SA for engine control is equal to or less than the end threshold value SC. This P45
If the determination is YES, in P46, it is determined whether the state where SA is equal to or smaller than the end threshold value SC has continued for 1000 msec. YES in this determination of P46
In the case of, the program shifts to P42 and the slip control is stopped.

If the determination in P45 or P46 is NO, it is determined in P47 whether the vehicle speed VS is equal to or higher than the second vehicle speed V2. If the determination in P47 is YES, the process returns to P48. After stopping the brake control while gradually reducing the brake fluid pressure to prevent the occurrence of slip, the brake flag is reset to 0 in P49. The gradual suspension of the brake control is performed by reducing the pressure reduction signal to the hydraulic pressure regulating valves 15L and 15R at predetermined time intervals, but the degree of pressure reduction at one time increases. Restrictions are imposed.

If the determination in P47 is NO, it is determined in P50 whether the brake fluid pressures of the left and right driving wheel brakes 7FL and 7FR have both become zero. This P50
If the determination is YES, the brake control is stopped in P51, and then the flow shifts to P49. The estimation of the brake fluid pressure can be indirectly known by various methods already proposed, but a sensor for directly detecting the brake fluid pressure can also be used.

If the determination in P50 is NO, in P52, it is determined whether or not the control signals to the hydraulic pressure regulating valves 15L, 15R both indicate pressure reduction.
If the determination is YES, it is determined whether or not the state where both the pressure reduction signals are 0 has continued for 500 msec. If the determination in P53 is YES, the brake control is stopped in P51. If the determination in P52 or P53 is NO, the process is terminated as it is (continuation of engine control and brake control).

Here, the brake switch S6 or S
7, if it is detected that the brake pedal 12 is depressed, the brake control is forcibly stopped by the interrupt processing for the flow chart.

FIG. 9 is a flowchart for changing the control gain. In this embodiment, the present control is performed using the following equation (1) with respect to the basic value determined by the feedback control equation so as to be the target value STB or STE for the brake control or the engine control. The amount is calculated, and the control gain GV in the equation (1) is changed. Current control amount = {previous control amount + basic value x GV} / 100 (1)

As is apparent from the above equation (1), as the control gain GV increases, the target value STB or STE
The response speed until the control amount corresponding to the above becomes faster. However, the control gain GV has a positive value when decreasing the applied torque to the driving wheels, and has a negative value when increasing the applied torque to the driving wheels. Of course, the control gain itself in the feedback control formula may be changed (for example, the response speed increases as the proportional coefficient or differential coefficient as the control gain increases).

Assuming the above, after the basic control gain GVB is set as the control gain GV in P61, it is determined in P62 whether or not the brake control is to be started, that is, at time t3 in FIG. It is determined whether or not there is. If the determination in P62 is YES, P63
In, the correction coefficient K1 is set according to the delay time from the time point t1 to the time point t3 when the engine control starts. As shown in FIG. 10, the correction coefficient K1 is set to be larger as the delay time is longer. Thereafter, at P64, the control gain GV at P61 is multiplied by the correction coefficient K1, and the changed control gain GV is set.

After P64 or when the determination of P62 is NO, after the slip control is started in P65,
It is determined whether or not the actual slip value has reached the engine target value STE for the first time. . If the determination in P65 is YES, in P66, the time from the time t1 when the engine control is started to the time when the target value STE is reached is set as T. Then, in P67, a correction coefficient K2 according to the time T is set. As shown in FIG. 11, the correction coefficient K2 is set to increase as the time T increases. Thereafter, at P68, the control gain GV at P61 or P64 is multiplied by the correction coefficient K2 to change the control gain GV.

After P68 or in the determination of P65, NO
In step P69, it is determined whether the actual slip value SA for engine control has become equal to or smaller than the end threshold value SC. If the determination in P69 is YES,
In P70, it is determined whether or not the control amount by the engine control is equal to or more than a predetermined value. In this determination of P70, YE
In the case of S, since there is a high possibility that re-slip will occur, the control gain GV is changed to a large value in P71. In the case of NO in the determination of P70, there is a low possibility that re-slip will occur. The control gain is changed to a smaller value. The degree of change in P71 and P72 may be set according to the magnitude of the control amount at that time, or may be a process of uniformly increasing or decreasing by a predetermined ratio.

After P71, P72, or when the determination in P69 is NO, in P73, it is determined whether or not the brake fluid pressures of the left and right driving wheels are both reduced. This P
If the determination in step 73 is YES, in step P74,
It is determined whether or not the control amount of the key control is equal to or greater than a predetermined value. If the determination in P74 is NO, the control gain GV is changed to a small value in P76, and Y is determined in P74.
In the case of ES, the control gain GV is changed to a large value in P75. The processing of P74 to P76 is
This corresponds to the process of P72.

After P75 and P76, or when the determination in P73 is NO, in P77, the control gain GV set as described above is executed (used for the calculation of the equation (1)).

Although the embodiment has been described, the slip value is calculated not as the difference between the drive wheel and the driven wheel, but as a ratio, for example, as the drive wheel speed / driven wheel speed, or (drive wheel speed-driven wheel speed). ) / Driven wheel speed.
The brake fluid pressure for the brake control is the same as that of the booster 11.
Alternatively, it may be generated by a dedicated pump without using. Further, the control threshold can be variously set in addition to the one shown in the embodiment. Further, the slip control may be performed only by the engine control or only the brake control.

When the control gain is changed by a control threshold value dedicated to one of the controls during slip control in both the engine control and the brake control, the changed control gain is used for the one control. Not only that, but also for the other control.

[Brief description of the drawings]

FIG. 1 is an overall system diagram showing an example of a vehicle to which the present invention is applied.

FIG. 2 is a sectional view showing a main part of the brake booster.

FIG. 3 is a diagram showing an input and output relationship with respect to a control unit.

FIG. 4 is a time chart schematically showing a control example of the present invention.

FIG. 5 is a flowchart showing a control example of the present invention.

FIG. 6 is a flowchart showing a control example of the present invention.

FIG. 7 is a flowchart showing a control example of the present invention.

FIG. 8 is a flowchart showing a control example of the present invention.

FIG. 9 is a flowchart showing a control example of the present invention.

FIG. 10 is a diagram showing a correction coefficient of a control gain.

FIG. 11 is a diagram showing a correction coefficient of a control gain.

[Explanation of symbols]

 Reference Signs List 1FL, 1FR Front wheel (drive wheel) 1RL, 1RR Rear wheel (driven wheel) 2 Engine 7FL-7RR Brake 8 Master cylinder 9 Torque adjusting means 11 Brake booster (power booster) 12 Brake pedal 15L, 15R Hydraulic pressure control valve 16L, 16R Open / close valve 38 Switching valve (switching between negative pressure supply and atmospheric pressure supply) U Control unit

────────────────────────────────────────────────── ─── Continued on the front page (51) Int.Cl. ⁶ Identification code FI F02D 45/00 330 F02D 45/00 330 345 345G (72) Inventor Chizumi Izumi 3-1, Fuchu-cho, Fuchu-cho, Aki-gun, Hiroshima Pine (72) Inventor Hiroaki Sakamoto 3-1, Shinchi, Fuchu-cho, Aki-gun, Hiroshima Prefecture Mazda Corporation (56) References JP-A-2-252930 (JP, A) JP-A-1-271618 ( JP, A) JP-A-1-315632 (JP, A) JP-A-63-205432 (JP, A) JP-A-1-145242 (JP, A) JP-A-2-23727 (JP, A) (58) ) Surveyed field (Int.Cl. ⁶ , DB name) B60K 41/20 F02D 29/02 311

Claims (4)

(57) [Claims] 1. A torque adjusting means for adjusting a torque applied to a driving wheel, a slip detecting means for detecting a slip value of a driving wheel with respect to a road surface, and a detected slip value detected by the slip detecting means is a first predetermined value. And controlling the torque adjusting means so that the detected slip value becomes a predetermined target value when the detected slip value is larger than the second predetermined value, which is smaller than the first predetermined value. A slip control means for terminating the control of the torque adjustment means when the slip amount becomes smaller than the second predetermined value; and a control amount when the control amount by the slip control means becomes larger than the second predetermined value. And control gain changing means for increasing the control gain of the slip control means as compared with when the value is small. . 2. A torque adjusting means for adjusting an applied torque to a driving wheel, a slip detecting means for detecting a slip value of the driving wheel with respect to a road surface, and a slip value detected by the slip detecting means being a first predetermined value. A slip control means for controlling the torque adjusting means so that the detected slip value becomes a predetermined target value smaller than the first predetermined value when the detected slip value is larger than the first predetermined value. Control gain changing means for increasing the control gain in the slip control means as the time from when the value becomes smaller than the predetermined value to the target value becomes longer. Slip control device. 3. A brake force adjusting means for independently adjusting a braking force on left and right driving wheels, a slip detecting means for detecting a slip value of a driving wheel with respect to a road surface, and a detected slip detected by the slip detecting means. A brake control means for controlling the brake force adjusting means so that the detected slip value becomes a predetermined target value when the value is larger than a predetermined value; and a brake force for the left and right drive wheels is controlled by the brake control means. Control gain changing means for increasing the control gain of the brake control means when the control amount of the brake control means at the time of reducing both is larger than when the control amount is small. A vehicle slip control device characterized by the above-mentioned. A first torque adjusting means for adjusting the torque generated by the engine; a second torque adjusting means for adjusting a braking force applied to the driving wheels; a slip detecting means for detecting a slip value of the driving wheels with respect to a road surface; When the detected slip value detected by the slip detecting means is larger than a first predetermined value, the slip control for controlling the first torque adjusting means is performed, while the detected slip value is smaller than the first predetermined value. A slip control means for performing a slip control for controlling the second torque adjusting means in addition to the first torque adjusting means when the detected slip value is larger than the second predetermined value; When the time from when the value becomes larger than the first predetermined value to when the value becomes larger than the second predetermined value is long, the slip control means is compared with when the time is short. A control gain changing means for increasing a control gain of the vehicle.