JPH1059154A - Anti-skid controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable any vehicle to be prevented from getting unstable by changing the control content of an anti-skid control means to the content of control at the time of anti-skid control practice limit because of approaching of the practice limit of the anti-skid control means when the total some of the control lasting time exceeds the preset period of time. SOLUTION: A solenoid valve 25 of 3-ports 3-positions structure makes integration of a control lasting time to be controlled so as to reduce the pressure in wheel cylinders 12 to 15, by aid of an electronic controller 30. The sum of thus integrated control lasting time is compared with a preset time, and according to this result of comparison, and when the total sum of the control lasting time exceeds the preset period of time, the control content of the anti- skid control means is changed to the control content at the time of anti-skid control practice limit time on the basis of such judgment that the practice limit time of the anti-skid control of the electronic controller 30 has approached. In this way, feeling of disorder of crews can be suppressed so that any unstableness of a vehicle can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an anti-skid control device capable of preventing wheels from slipping when a brake is actuated and ensuring the running stability of a vehicle. The present invention relates to a low-cost type anti-skid control device not provided with a pump for discharging the brake fluid flowing into the brake fluid storage means.

[0002]

2. Description of the Related Art Conventionally, as a vehicle brake pressure control device, for example, one disclosed in Japanese Patent Application Laid-Open No. 49-1968, "Anti-sticking device" is known.

[0003]

In the above-described brake pressure control device for a vehicle, etc., a control valve for increasing / decreasing pressure and a reservoir (corresponding to a storage means) for storing depressurized oil are constituted. A pump for returning the decompressed oil to the master cylinder is configured as an anti-skid actuator. However, when this pump is provided, a motor or the like for driving the pump is naturally required, which causes an increase in the size of the anti-skid control device and also contributes to an increase in price.

Therefore, the present invention employs an anti-skid control device without a pump. In this case, the brake fluid that flows out of the wheel cylinder during the period from the start to the end of the anti-skid control is discharged from the master cylinder. It only decreases from in the pipeline to the wheel cylinder,
No addition of brake fluid is performed. Therefore, it is anticipated that the master will bottom out and the wheel cylinder pressure cannot be increased, or the reservoir will be full, which will limit the execution of anti-skid control.

Accordingly, the present invention provides an anti-skid control device without a pump, which accurately determines the execution limit of the anti-skid control and switches the anti-skid control, thereby reducing the occupant's discomfort and making the vehicle unstable. It is an object of the present invention to provide an anti-skid control device capable of minimizing this.

[0006]

According to the present invention, there is provided an anti-skid control means for outputting a control signal for adjusting a brake fluid pressure applied to a wheel cylinder in accordance with a detection result of a slip state detecting means. And a control valve for reducing the brake pressure applied to the wheel cylinder in response to a control signal from the anti-skid control means, and a housing for storing the brake fluid corresponding to the reduced pressure passed through the control valve when the brake fluid pressure applied to the wheel cylinder is reduced. And an anti-skid control device that does not include a pump for discharging the brake fluid stored in the storage device to the master cylinder side during execution of the anti-skid control device. Control time to accumulate control continuation time controlled to reduce cylinder pressure Calculating means, comparing means for comparing the sum of the control continuation time accumulated by the control time integrating means with the predetermined time, and comparing the result of the comparing means, when the sum of the control continuation time is equal to or more than the predetermined time, It is characterized in that the control content of the anti-skid control means is changed to the control content at the time of execution limit of the anti-skid control, assuming that the execution limit of the anti-skid control means is approaching.

That is, in the anti-skid control device without a pump, the vehicle stops or the wheel slips for a predetermined time or more after the initial control such as the reduction of the wheel cylinder pressure due to the increase of the wheel slip state. During the anti-skid control until the anti-skid control is completed by satisfying the condition such as running out, the amount of brake fluid flowing into and stored in the storage means is increasing. This is because there is no pump for discharging the brake fluid flowing into the storage means toward the master cylinder or the wheel cylinder. Therefore, depending on the road surface condition or the vehicle speed at the beginning of the control execution, the flow into the reservoir may be so large that the execution of the anti-skid control may not be possible. However, in the present invention, since the reservoir inflow amount is software-estimated by the decompression time counter, it is possible to accurately change the control before or after the anti-skid control becomes infeasible. Thus, the reliability of an anti-skid control device of a type not provided with a pump can be improved, and an uncomfortable feeling of an occupant can be reduced.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described based on specific embodiments. FIG. 1 is a configuration diagram showing a brake pressure control device for a vehicle. In FIG. 1, 11 is 2
A tandem master cylinder (M / M), which is a brake master cylinder with pistons arranged in series for system brakes
C), 12 and 13 are respective wheel cylinders (W / C) of left and right front wheels FL and FR (rolling wheels), and 14 and 15 are respective wheel cylinders (W / C) of left and right rear wheels RL and RR (driving wheels). / C), and two brake hydraulic piping paths of a front-rear separation type are formed.

Reference numeral 16 denotes a wheel speed sensor, which is mounted on a differential of a rear wheel and detects a rotation speed of a drive shaft. Reference numeral 21 denotes a proportioning valve (PV), which reduces the rate of pressure increase to the wheel cylinders 14 and 15 of the left and right rear wheels RL and RR when the pressure from the master cylinder 11 exceeds a predetermined value. .

A brake pedal depression switch 23 detects whether or not the driver has depressed the brake pedal 22. Reference numeral 25 denotes a solenoid valve (3-position valve) having a three-port three-position structure, which is a switching valve for increasing / holding / reducing the pressure of the wheel cylinder oil pressure. In the position A, the master cylinder 11 and the rear wheel cylinders 14 and 15 are connected. To perform a normal brake pressure control operation. At the position B, the brake pressure of the wheel cylinders 14 and 15 is maintained.
At the C position, the brake pressure of the wheel cylinders 14 and 15 is reduced by communicating the wheel cylinders 14 and 15 with the oil reservoir 26 of the master cylinder 11.

Reference numerals 27 and 28 denote check valves. The check valve 27 prevents air from entering into the brake hydraulic piping upstream of the check valve 27, and the check valve 28 controls the brake pressure of the wheel cylinders 14 and 15 to the master. The brake pressure of the cylinder 11 is prevented from rising. An electronic control unit (ECU) 30 controls an electromagnetic valve (three-position valve) 25 according to signals from the wheel speed sensor 16 and the brake pedal depression switch 23, and brakes the wheel cylinders 14, 15 of the rear wheels. Adjust pressure.

FIG. 3 is a time chart showing a basic control pattern of the apparatus of this embodiment based on a flowchart of FIG. 2 showing a processing procedure of the electronic control unit 30 in the vehicle brake pressure control apparatus of FIG. This will be described with reference to FIG. In step 100, initialization of each flag and each numerical value, such as checking the operation of each unit and turning off the control-in-progress flag and setting the value of the pressure reduction counter CT to 0, is performed as initialization.

Next, the routine proceeds to step 102, where a time wait is executed to repeat the following processing routine at predetermined time intervals Tms (for example, Tms). Then, a predetermined time T
After elapse of ms, the determination in step 102 becomes YES, and the process proceeds to step 104. In step 104,
Loading of the wheel speed V _W from a signal wheel speed sensor 16 outputs is performed, the wheel acceleration A _W is calculated based on V _W.

Next, the routine proceeds to step 106, where the pseudo vehicle speed _Vb is calculated by the following equation.

(Equation 1) V_b(N) = MED [V_W(N), V_b(N-
1) + K_UP・ T, V_b(N-1) K_dw・ T] However, K_UPIs the acceleration upper limit, K_dwIs the upper limit of deceleration. Up
The above expression is the previous and current pseudo vehicle speed V_bSpeed difference,
Acceleration K during acceleration _UPBelow the speed due to
Speed K_dwThe speed is limited to below.

That is, the wheel speed V _W and the speed (V _b (n−1) + K _UP · T) obtained when the vehicle is accelerated with the acceleration K _UP from the pseudo body speed V _b (n−1) obtained last time. The speed ( _Vb (n-1) + _Kdw.T ) obtained by decelerating at the deceleration _Kdw from the previously obtained pseudo vehicle speed _Vb (n-1) is compared with the intermediate speed. It is assumed that the pseudo vehicle speed is _Vb .
Then, the process proceeds to step 108, where the master cylinder 11
It is determined that the bottom of the brake pedal is approaching the bottom, and it is determined whether or not the brake pedal 22 is depressed in order to determine a reset condition of the pressure reduction counter CT.

At this time, if the brake pedal 22 is not depressed and the brake pedal depression switch 23 is OFF, the determination in step 108 is YES, the process proceeds to step 110, and after the pressure reduction counter CT is reset to 0, Move to step 112. If the brake pedal 22 is depressed in step 108 and the brake pedal depression switch 23 is ON, the determination is NO, the value of the pressure reduction counter CT is held, and the routine proceeds to step 112.

In step 112, the decompression counter C
T is compared with a reference value KT for determining the bottom of the master cylinder 11. That is, it is determined whether or not CT> KT and the bottom of the master cylinder 11 is near. Here, before the brake pressure control, the pressure reduction counter CT = 0, and the determination in step 112 is NO.
Then, the process proceeds to step 114.

At step 114, it is determined whether or not the control flag indicating the brake pressure control state is ON, that is, whether or not the brake pressure control is currently being performed. If the control-in-progress flag is not ON, it is determined that the brake pressure control has not yet been performed, and the routine proceeds to step 116. In step 116, the difference between the estimated vehicle speed V _b and the wheel speed _{V W (V b -V W)} , i.e., the slip amount K for selecting the amount of slip and brake pressure control start wheel
Magnitude of V ₁ is compared.

The amount of wheel slip is small, that is, V _b −
If V _W ≦ KV ₁ , the determination at Step 116 is NO, and the routine goes to Step 118. In step 118, the control-in-progress flag is turned off, the routine proceeds to step 120, and the solenoid valve (three-position valve) 25 is set to the position A, which is the pressure increasing position. Then, the routine returns to step 102 to repeat the same processing.

If it is determined in step 112 that CT> KT and that the bottom of the master cylinder 11 is close to the bottom, the process proceeds to step 118, in which the control flag is turned off, and After setting the solenoid valve (three-position valve) 25 to the position A, which is the pressure increasing position, the process returns to step 102. Even if the brake pedal 22 is not depressed or is depressed, the above-described routine is repeatedly executed in a state where the wheels are not slipping.

Then, when the brake pedal 22 is depressed, a wheel slip occurs, and as shown in FIG.
The difference between the pseudo vehicle speed V _b and the wheel speed V _W (V _b -V _W)
Becomes larger, and in step 116 described above, V _b −
If V _W > KV ₁ holds, the determination is YES and the routine proceeds to step 122. In step 122, first, the accumulated value of the decompression time is measured by adding 1 to the decompression counter CT.

Next, the routine proceeds to step 124, in which the control flag indicating the brake pressure control state is turned ON, and the routine proceeds to step 126, where the solenoid valve (three-position valve) 25 is switched to the C position, which is the pressure reducing position. , And returns to step 102 described above. In the next execution loop in which the control-in-progress flag is turned on in the above-mentioned step 124, the above-mentioned determination in step 114 is YE
Since the result is S, the process proceeds to step 128.

In step 128, a second determination value KV ₂ for determining the tendency of the wheel to recover from the slip state after the pressure is reduced.
Is compared with the slip amount. Here, KV ₂ ≦ KV ₁
And Then, V _b -V _W> KV ₂ at step 128
Is satisfied, that is, if the wheels are slipping and the slip state has not been sufficiently recovered, the determination is YES, and the routine proceeds to step 130.

In step 130, the polarity of the wheel acceleration A _W , that is, positive or negative, is determined. The negative wheel acceleration A _W means that the wheel is in the direction in which the slip amount increases due to the brake pressure, as shown in FIG. 3. The process proceeds to step 122 and thereafter, the pressure reduction counter CT is updated, the control-in-progress flag is kept ON, and the solenoid valve (three-position valve) 25
Is set in the C position which is the decompression position,
Return to 02. In this way, during the pressure reduction control period, as shown in FIG. 3, the value of the pressure reduction counter CT is increased.

When the oil pressure of the wheel cylinders 14 and 15 decreases as the above flow is repeated, A _W ≧ 0, that is, as shown in FIG. 3, the wheel speed increases and the slip amount of the wheel decreases. When the tendency is changed, the determination in step 130 is NO, and the process proceeds to step 132. In step 132, in order to maintain the current oil pressure of the wheel cylinders 14, 15, the solenoid valve (three-position valve) 25 is set to the position B, which is the holding position, and the process returns to step 102, where the same processing is performed. repeat.

As shown in FIG. 3, the above flow is repeated, as shown in FIG. 3, when the wheel speed is recovered by reducing and maintaining the brake pressure, and the slip amount of the wheel is reduced to a predetermined value, the _Vb- V _W ≦ KV ₂ holds, and the routine goes to step 134. In step 134, it is determined whether or not the output of the step pressure increasing pattern for repeating the output of the pressure increasing and the holding for the determined time has been completed.

At first, since the output of the step pressure increase pattern has not been completed, the determination in step 134 is N.
O, the process proceeds to step 136, and the solenoid valve (three-position valve) 25 is set to the A or B position, which is a pressure increasing or holding position, according to a predetermined step pressure increasing pattern as shown in FIG. . The above flow is repeated, and as shown in FIG. 3, when the hydraulic pressure of the wheel cylinders 14, 15 gradually increases, the slip amount of the rear wheel increases again, and the determination in the above step 128 becomes YES, and the steps 130 and The processing in steps 122 to 126 is executed, and the brake pressure control of reducing the oil pressure of the wheel cylinders 14 and 15 is repeated.

When the above-described cycle is repeated and the vehicle stops or the brake pedal 22 is released, step 1
Since the rear wheels do not slip even if the hydraulic pressure of the wheel cylinders 14 and 15 is continuously increased in the output of the step pressure increasing pattern in which the pressure of the solenoid valve (three-position valve) 25 is increased or held, the determination in step 128 is made. Is always NO.
Finally, the output of the step pressure increase pattern is completed, the determination in step 134 becomes YES, the process proceeds to step 118 described above, the control-in-progress flag is turned off, and in step 120 the solenoid valve (three-position valve) 25 Is set to the position A which is the pressure increasing position, and the antilock control is ended.

By loosening the brake pedal 22,
When the brake pedal depression switch is turned off, the determination in step 108 becomes YES as described above, and the pressure reduction counter CT updated in step 122 during the brake pressure control is reset. The above is the brake pressure control in a normal wheel slip state.

Here, a case in which the amount of pressure reduction is abnormally large for some reason and the bottom of the master cylinder 11 is approaching will be described. If the decompression counter CT continues to be added in step 122 described above, then in step 112, C
T> KT. Therefore, the determination in step 112 is YE
In S, the routine proceeds to step 118, where the control flag is turned off as described above, and in step 120, the solenoid valve (three-position valve) 25 is set to the position A, which is the pressure increasing position, and the normal brake pedal The control returns to the brake pressure control corresponding to the stepping pressure of No. 22.

If the wheels start slipping again in this state, the brake pedal depression switch 23 is ON until the brake pedal 22 is returned, and the value of the pressure reduction counter CT is held. Is Y
It is ES and does not start brake pressure control again. Then, when the brake pedal 22 is returned, the pressure reduction counter CT is cleared to 0 in step 110, so that the brake pressure control can be executed again.

In the above embodiment, the lock tendency judging means is steps 116, 128 and 130, the pressure control means is steps 120, 126, 132 and 136, the communicating means is a solenoid valve (three-position valve) 25, and the detecting means. Is Step 1
12. The pressure control changing means is achieved in steps 118 and 124. FIG. 4 is a configuration diagram showing a second embodiment as another embodiment of the vehicle brake pressure control device.

In this embodiment, the master cylinder 1
The case where the differential pressure switch 18 of the front system and the rear system of the master cylinder 11 is used for bottom determination of 1 is shown. In addition, in the same configuration as the above-described first embodiment, the same number is assigned and the description is omitted. Reference numeral 18 denotes a differential pressure switch. The differential pressure switch 18 detects that a differential pressure, for example, about 5 atm, has been generated between the front system master cylinder oil pressure and the rear system master oil pressure.

In the figure, the wheel speed sensor 16
1, 162 are disposed on the left and right rear wheels RL, RR, respectively. Next, the electronic control unit 30 in the embodiment of FIG.
A description will be given based on the flowchart of FIG. Here, the electronic control unit 3 in the first embodiment
The same steps as those in the flowchart of FIG. 2 showing the processing procedure of 0 are denoted by the same step numbers, and description thereof is omitted.

In step 103, the left and right rear wheels RL, RR
, The wheel speeds V _W RL and V _W RR and the wheel accelerations A _W RL and A _W RR are calculated independently. Then, the process proceeds to step 105, is calculated as the wheel velocity V _W RL, V _W RR and a wheel acceleration A _W RL, A _W average wheel speeds respective average RR V _W and the average wheel acceleration A _W.

That is,

[0037]

(Equation 2) Is calculated.

Then, step 122 in the flowchart of FIG. 2 is deleted, and steps 108 to 1
Step 12 is replaced by step 111. Step 11
At 1, it is determined whether the output of the differential pressure switch 18 is ON. If the differential pressure switch 18 is off and the master cylinder 11 is not in the bottomed state,
1 is NO, the process proceeds to step 114, and when the differential pressure switch 18 is turned on and the master cylinder 11 is in the bottomed state, the determination in step 111 is YES, and the process proceeds to step 118. The same processing is performed.

The use of the differential pressure switch 18 causes a differential pressure even when the front piping is defective, so that the differential pressure switch 18 is turned on. Therefore, also in this case, the brake pressure control ends, so that the normal brake pressure control is performed at the rear, and the safety of the vehicle can be ensured. In the above-described second embodiment, the lock tendency judging means is steps 116, 128, and 130, the pressure control means is steps 120, 126, 132, and 136, the communicating means is an electromagnetic valve (three-position valve) 25, and the detecting means is a differential pressure. Switch 1
8. The pressure control changing means is achieved in steps 118 and 124.

FIG. 6 is a block diagram showing a third embodiment as another embodiment of the vehicle brake pressure control device. still,
In the configuration similar to that of the above-described embodiment, the same number is assigned and the description is omitted. In this embodiment, a differential pressure switch A181 between the front system and the rear system of the master cylinder 11 is used for bottom determination of the master cylinder 11,
Also, a solenoid valve (3-position valve) for determining the end of brake pressure control
Differential pressure switch B for detecting differential pressure between 25 input / output ports
182 are used.

Then, if the output of the step pressure increase pattern of step 134 in the flowchart of FIG. 2 is completed, the processing for terminating the brake pressure control is replaced with the processing for the upstream side and the downstream side of the solenoid valve (three-position valve) 25. When the oil pressure difference disappears, a process for terminating the brake pressure control is executed.
Further, in this embodiment, when the differential pressure switch A181 is turned on and it is determined that the bottom of the master cylinder 11 is near, the brake pressure control that does not output the step pressure increasing pattern is performed, so that the solenoid valve ( The opportunity to set the three-position valve (25) to the C position, which is the pressure reducing position, is reduced, and the brake pressure is controlled so that the master cylinder 11 does not substantially bottom.

Next, a description will be given based on the flowchart of FIG. 7 showing the processing means of the electronic control unit 30 in the embodiment of FIG. Here, the same steps as those in the flowchart of FIG. 2 showing the processing procedure of the electronic control device 30 in the first embodiment are denoted by the same step numbers, and description thereof is omitted.

When the determination in step 128 is NO, that is, when the slip amount of the wheel is reduced during the brake pressure control, the process proceeds to step 133. In step 133,
It is determined whether or not the differential pressure switch B182 for detecting the differential pressure between input and output of the solenoid valve (three-position valve) 25 is OFF. If the differential pressure switch B182 is OFF and there is no differential pressure, there is no need to perform the brake pressure control. Therefore, the determination in step 133 is YES, the process shifts to step 118, and the control for the brake shock is ended.

If the differential pressure switch B 182 is ON, it is necessary to perform the brake pressure control. In step 135, it is determined whether the differential pressure switch A181 for detecting the differential pressure between the front system master cylinder oil pressure and the rear system master oil pressure is ON, that is, whether or not the bottom of the master cylinder 25 is near.

If there is no problem when the differential pressure switch A 181 is turned off, the process proceeds to step 136, and the step of increasing the pressure of the solenoid valve (three-position valve) 25 is executed. In step 135, the differential pressure switch A181 is turned on.
Is determined, the routine proceeds to step 132, where the solenoid valve (3
The processing of the held output is executed for the position valve 25.

According to this flow, occurrence of wheel slip due to step pressure increase is eliminated. Therefore, the chance of reducing the pressure thereafter is reduced, and the bottoming of the master cylinder 11 can be substantially prevented. If the vehicle stops in this state and the depression of the brake pedal 22 is released, a solenoid valve (3-position valve)
Since there is no differential pressure between the input and the output of step 25, the determination in step 133 is YES, and the process proceeds to step 118 in the same manner as described above, and the brake pressure control ends.

In the above third embodiment, the lock tendency judging means is steps 116, 128, 130, the pressure control means is steps 120, 126, 132, 136, the communicating means is a solenoid valve (three-position valve) 25, The means is achieved by the differential pressure switch A181 and the differential pressure switch B182, and the pressure control changing means is achieved by steps 118 and 124. In addition to the above-described embodiment, the determination of the bottom of the master cylinder may be performed by mechanically measuring the stroke of the master cylinder or by using a flow meter in a return circuit to the oil reservoir.

Further, the bottom of the master cylinder is determined,
Although the brake pressure control is increased immediately, the hydraulic pressure may be gradually increased according to a step pressure increase pattern, and the brake pressure control may be terminated. Further, the bottom of the master cylinder is determined, and the brake pressure control is terminated. However, the brake pressure control may be performed by holding without increasing the pressure or by reducing the pressure.

As described above, the pressure reduction control of the pressure control is achieved by communicating the wheel cylinder with the oil reservoir of the master cylinder, and by detecting whether or not the brake fluid amount has reached a predetermined amount, the pressure is reduced. No pump is required because control is changed or discontinued. In the embodiments described above, the brake pressure control device that can adopt the configuration that is a feature of the present invention has been described. However, the feature of the present invention will be described below.

That is, the solenoid valve (three-position valve) 25 and the proportioning valve 2 shown in FIG. 1, FIG. 4 and FIG.
1 and the like are integrally assembled to the master cylinder 11 to form a structure as shown in FIG. 8, thereby further reducing the size and improving the mountability of the vehicle. In this structure, the master cylinder 52, the solenoid valve (three-position valve) 54, the proportioning valve 56, etc.
Sharing.

In the housing 60, a piston 62,
64 are slidably fitted in an oil-tight manner, so that pressurizing chambers 66 and 68 are formed. And the piston 62,
Numeral 54 indicates a state in which the pressure chambers 66 and 68 are retracted by springs 72 and 74 to the retracted end positions where they come into contact with the stoppers 76 and 78, respectively. Has become.

Here, the wheel cylinders of the left and right rear wheels RL, RR are depressurized when the solenoid valve (three-position valve) 54 is set to the C position. The order of the reservoir 86 is as follows. When the pistons 62 and 64 are depressed by the brake pedal, the master cylinder 52 slides to the left in the figure, and when the seal material 88 passes through the port 82 and the seal materials 88 and 89 close the port 82, the pressure reduction path is reduced. Is shut off, so that the pressure cannot be reduced mechanically before bottoming out.

[Brief description of the drawings]

FIG. 1 is a diagram showing an example of piping of a brake system using the present invention.

FIG. 2 is a flowchart illustrating an example of a control flow in the electronic control unit.

FIG. 3 is various time charts when a flow in the electronic control unit is executed.

FIG. 4 is a diagram showing an example of piping of a brake system using the present invention.

FIG. 5 is a flowchart illustrating an example of a control flow in the electronic control unit.

FIG. 6 is a diagram showing an example of piping of a brake system using the present invention.

FIG. 7 is a flowchart illustrating an example of a control flow in the electronic control unit.

FIG. 8 is an example of a configuration showing features of the present invention.

[Explanation of symbols]

 11, 52 Master cylinder 12, 13, 14, 15 Wheel cylinder 22 Brake pedal 25 Solenoid valve (3-position valve) 26 Oil reservoir (Reservoir) 27, 28 Check valve 30 Electronic control unit 62, 64 Piston (Master piston) 60 Housing (Master cylinder housing)

Claims (5)

[Claims] 1. A master cylinder that generates a master cylinder pressure in response to an operation of a brake pedal operated by an occupant during braking of a vehicle, a wheel cylinder that receives the master cylinder pressure and applies a wheel braking force to wheels, Slip state detecting means for detecting a slip state of a wheel, anti-skid control means for outputting a control signal for adjusting a brake fluid pressure applied to the wheel cylinder according to a detection result of the slip state detecting means, and the anti-skid control A control valve that receives a control signal from the means to reduce the brake pressure applied to the wheel cylinder, and a storage unit that stores the reduced pressure brake fluid that has passed through the control valve when the brake fluid pressure applied to the wheel cylinder is reduced. And the brake fluid stored in the storage means is supplied to the anti-skip. An anti-skid control device that does not include a pump that discharges to the master cylinder side during execution of the skid control means, wherein the control duration is controlled by the anti-skid control means so that the control valve reduces the wheel cylinder pressure. Control time integrating means for integrating the control continuation time integrated by the control time integrating means and a predetermined time; and a comparison result by the comparing means, wherein the sum of the control continuation time is When a predetermined time or more has elapsed, the execution limit of the anti-skid control unit is approached and the control content of the anti-skid control unit is changed to the control content at the time of execution limit of the anti-skid control. apparatus. 2. The anti-skid control device according to claim 1, wherein the storage means is a master reservoir that stores excess brake fluid in the master cylinder. 3. The anti-skid control device according to claim 1, wherein a prohibition command for prohibiting the anti-skid control is output as the control content at the time of execution limit of the anti-skid control. 4. The control content at the time of execution limit of the anti-skid control is to output a prohibition command for prohibiting the anti-skid control after gradually increasing a brake pressure applied to the wheel cylinder for a predetermined time. Item 1
3. The anti-skid control device according to claim 1. 5. The vehicle brake device according to claim 1, further comprising a storage unit that stores the control duration time.