JP3689209B2 - Antilock brake control device for vehicle - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an antilock brake control device for a vehicle, and more particularly to a reflux type antilock brake control device in which hydraulic pressure released from front and rear wheel brakes is returned by a pump when the brake fluid pressure is reduced.
[0002]
[Prior art]
Conventionally, such an anti-lock brake control device is already known, for example, in Japanese Patent Laid-Open No. 1-297349 and Japanese Patent Laid-Open No. 5-330416. The brake fluid released from the engine is recirculated to the master cylinder side by a pump, and Japanese Patent Laid-Open No. 5-330416 discloses a cut valve for avoiding the occurrence of kickback due to recirculation to the master cylinder side. Thus, the brake fluid is recirculated downstream of the cut valve in a state where the master cylinder is disconnected from the front wheel and rear wheel brakes.
[0003]
[Problems to be solved by the invention]
However, in the above-mentioned Japanese Patent Application Laid-Open No. 1-297349, it is necessary to generate a discharge pressure by a pump that can overcome the output hydraulic pressure of the master cylinder, and Japanese Patent Application Laid-Open Nos. 1-297349 and 5-330416. In any of the publications, the brake fluid pressures of the front and rear wheel brakes are increased by the discharge fluid pressure of the pump. For this reason, not only the capacity of the pump becomes relatively large, but also it is necessary to discharge from the pump a fluid pressure sufficient to sufficiently increase the front wheel brake, which requires a relatively high fluid pressure. It is necessary to set the pressure sufficiently high, so that the size of the pump device, particularly the motor, is increased, and the antilock brake control device is heavy and large.
[0004]
The present invention has been made in view of such circumstances, and it is possible to reduce the size of the pump device and to reduce the size and weight of the entire antilock brake control device. The purpose is to provide.
[0005]
[Means for Solving the Problems]
To achieve the above object, the present invention provides an output hydraulic pressure path that leads to an output port of a master cylinder; a front wheel brake hydraulic pressure path that leads to a front wheel brake; a rear wheel brake hydraulic pressure path that leads to a rear wheel brake; A branch hydraulic pressure path branched from the front wheel brake hydraulic pressure path; a release path capable of commonly guiding brake hydraulic pressure released from the front and rear wheel brakes; a pump having the release path connected to the suction port; and a front wheel Switches between the hydraulic pressure action state that allows the brake hydraulic pressure path to communicate with the output hydraulic pressure path but is disconnected from the release path, and the hydraulic pressure release condition that allows the front wheel brake hydraulic pressure path to communicate with the release path but is disconnected from the output hydraulic pressure path. A first hydraulic pressure control valve means provided between the front wheel brake hydraulic pressure path and the output hydraulic pressure path and the release path as possible; allows the rear wheel brake hydraulic pressure path to communicate with the branch hydraulic pressure path but is disconnected from the release path; Hydraulic action state and after A second fluid provided between the rear brake fluid pressure passage, the branch fluid pressure passage, and the release passage so that the fluid pressure release state that allows the brake fluid pressure passage to communicate with the release passage but is disconnected from the branch fluid pressure passage can be switched. A pressure control valve means; a first return path connecting between the discharge port of the pump and the output hydraulic pressure path; provided in the first return path allowing only the flow of the brake fluid from the pump to the output hydraulic pressure path side. A first check valve; a second check valve provided in the branch hydraulic pressure passage only allowing the brake fluid to flow from the front wheel brake hydraulic pressure passage to the rear wheel brake hydraulic pressure passage side; a second check valve; A second return path connecting the branch hydraulic pressure path between the second hydraulic pressure control valve means and the discharge port; and controlling each operation of the first and second hydraulic pressure control valve means and anti-lock brake control And a control unit for operating the pump. And units, the anti-lock when the both causes boosted brake hydraulic pressure of the front wheel and rear wheel brake in a brake control state first and second pressure control valve means of the liquid pressure acting state and the hydraulic released state substantially antiphase so as to be characterized in that that controls the operation of Ryoeki pressure control valve means.
[0006]
According to such a configuration, during normal braking, by a both liquid pressure acting state of the first and second pressure control valve means, the hydraulic pressure that is output to the output fluid pressure channel depending on the actuation of the master cylinder Acts on the front wheel brake via the first hydraulic pressure control valve means and the front wheel brake hydraulic pressure path, and the hydraulic pressure in the output hydraulic pressure path is the first control valve means, the front wheel brake hydraulic pressure path, the branch hydraulic pressure path, and the second control. It acts on the rear wheel brake via the valve means and the rear wheel brake hydraulic pressure path, and the braking force can be exerted on the front wheel and the rear wheel brake. At this time, the first check valve functions to prevent the hydraulic pressure in the output hydraulic pressure path from acting on the first return path, the second return path, and the branch hydraulic pressure path.
Also, particularly during anti-lock brake control, the pump operation is started and the first and second hydraulic pressure control valve means are released to release the hydraulic pressure of the front and rear wheel brakes to the release path. It is possible to reduce the hydraulic pressures of the front and rear wheel brakes and increase the pressure by operating the first and second hydraulic pressure control valve means so as to repeat the hydraulic pressure action state and the hydraulic pressure release state. In addition, the brake fluid pressures of the front wheels and the rear wheels can be substantially maintained by repeating the pressure reduction in a short cycle. Further, when the brake fluid pressure of one of the front and rear wheel brakes is increased in this anti-lock brake control state (and therefore the pump is operating) , the hydraulic pressure control valve means on the side corresponding to the wheel brake to be increased is hydraulically operated . The brake fluid pressure of the front wheel brake is increased mainly by the output fluid pressure of the master cylinder, and the brake fluid pressure of the rear wheel brake is increased by the pump discharge fluid pressure. When increasing the brake fluid pressure of the rear wheel brake, the brake fluid pressure of the front wheel brake is mainly used as the output fluid of the master cylinder by setting the hydraulic pressure action state and the hydraulic pressure release state of both hydraulic pressure control valve means to be in opposite phases. The brake fluid released from the front wheel brake is increased by the pressure and increased by the pump to act on the rear wheel brake. It can pressure increase the brake fluid pressure of the rear wheel brake by Rukoto. That is, the capacity and discharge pressure of the pump need only be set to such an extent that the brake fluid pressure of the rear wheel brake can be increased during anti-lock brake control. If the rear wheel brake is smaller and lower in pressure than the front wheel brake, Combined with good things, it is possible to reduce the size of the pump. Thus, the second check valve functions to prevent the brake fluid from flowing from the branch hydraulic pressure passage to the front brake hydraulic pressure passage when the rear wheel brake is increased.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described based on examples of the present invention shown in the accompanying drawings.
[0008]
1 to 5 show a first embodiment of the present invention. FIG. 1 is a circuit diagram showing the configuration of an antilock brake control device for a vehicle. FIG. 2 is an operation timing of both solenoid valves when the brake pressure is maintained. FIG. 3 is a diagram showing the brake pressure change in correspondence with each other, FIG. 3 is a diagram showing the actuation timing of both solenoid valves and the change in brake pressure when the front wheel brake pressure is increased and the rear wheel brake pressure is reduced, and FIG. FIG. 5 is a diagram showing the operation timing of both solenoid valves and the change in brake pressure when the brake pressure is reduced and the rear wheel brake pressure is increased. FIG. 5 shows the operation timing of both solenoid valves when both the front wheel and rear wheel brakes are increased. It is a figure which shows a brake pressure change corresponding to each other.
[0009]
First, in FIG. 1, an output hydraulic pressure path 4 is connected to an output port 3 of a master cylinder 2 that operates in response to a depression operation of the brake pedal 1, and a front wheel brake hydraulic pressure path 5 is connected to a front wheel brake _BF that is a disc brake. There are connected, the rear wheel brake fluid pressure channel 6 is connected to the rear wheel brake B _R is a small disc brakes than the front wheel brake B _F, branch passages 7 is branched from the front wheel brake fluid pressure passage 5 The
[0010]
Pump P driven by a motor M is of the front wheel brake small extent necessary to B than _F pressure increase the rear wheel brake B _R, which requires a small and low pressure of the brake pressure, and low discharge pressure. A release path 10 is connected to the suction port 8 of the pump P via a suction valve 9 that allows only the brake fluid to flow toward the suction port 8. The suction valve 9 is built in the pump P. It may be done.
[0011]
Between the front wheel brake hydraulic pressure path 5, the output hydraulic pressure path 4 and the release path 10, a three-port two-position type first electromagnetic valve 11 serving as a first hydraulic pressure control valve means is provided. Between the brake hydraulic pressure path 6, the branch hydraulic pressure path 7 and the release path 10, a 3-port 2-position type second electromagnetic valve 12 as a second hydraulic pressure control valve means is provided. Thus, the first electromagnetic valve 11 allows the front wheel brake hydraulic pressure path 5 to communicate with the output hydraulic pressure path 4 during demagnetization but is disconnected from the release path 10 and the front wheel brake hydraulic pressure path 5 to be excited during excitation. It is possible to switch between a hydraulic pressure release state that leads to the release path 10 but is disconnected from the output hydraulic pressure path 4, and the second solenoid valve 12 connects the rear wheel brake hydraulic pressure path 6 to the branch hydraulic pressure path 7 during demagnetization. Is switched between a hydraulic pressure action state that is communicated with the release path 10 but is disconnected from the release path 10 and a hydraulic pressure release condition that allows the rear wheel brake hydraulic pressure path 6 to communicate with the release path 10 but is disconnected from the branch hydraulic pressure path 7 during demagnetization. Is possible.
[0012]
The discharge port 13 of the pump P is connected to one end of the first and second return passages 15 and 16 via a discharge valve 14 that allows only the flow of brake fluid from the discharge port 13 side. 14 may be incorporated in the pump P. Thus, the other end of the first reflux path 15 is connected to the output hydraulic pressure path 4, and the other end of the second reflux path 16 is connected to the branch hydraulic pressure path 7. Moreover, a first check valve 17 that does not have a spring that exerts a spring force in the valve opening direction is allowed in the first return path 15 only to allow the brake fluid to flow from the pump P to the output hydraulic pressure path 4 side. The brake fluid pressure path 7 from the front wheel brake fluid pressure path 5 to the rear wheel brake fluid pressure path 6 is provided between the connecting portion of the second return path 16 and the front wheel brake fluid pressure path 5. A second check valve 18 that allows only circulation is provided.
[0013]
A first orifice 19 is provided in the output hydraulic pressure path 4 and the front wheel brake hydraulic pressure path 5 from the output port 3 to the branch portion of the branch hydraulic pressure path 7, and the first orifice 19 is provided in the front wheel brake fluid. The first electromagnetic valve 11 may be incorporated so as to be interposed between the front-wheel brake hydraulic pressure path 5 and the output hydraulic pressure path 4 when demagnetizing the pressure path 5 through the output hydraulic pressure path 4. Also branch passages branch passages 7 until the rear wheel brake B _R from the second check valve 18 in 7 and rear wheel brake hydraulic pressure passage 6, even aperture size than the first orifice 19 large The second orifice 20 is also provided, and the second orifice 20 also has the rear wheel brake hydraulic pressure path 6 and the branch hydraulic pressure path 7 when demagnetizing the rear wheel brake hydraulic pressure path 6 to the branch hydraulic pressure path 7. It may be incorporated in the second electromagnetic valve 12 so as to be interposed therebetween. Furthermore, between the branch hydraulic pressure path 7 and the rear wheel brake hydraulic pressure path 6 so as to bypass the second electromagnetic valve 12 and the second orifice 20, the rear wheel brake hydraulic pressure path 6 is directed to the branch hydraulic pressure path 7 side. A third check valve 21 that allows only the flow of the brake fluid is provided.
[0014]
The operation of the motor M for driving the pump P is controlled by the control unit C so that the pump P is rotated during the anti-lock brake control, and the excitation and excitation of the first and second solenoid valves 11 and 12 are performed. Demagnetization is also controlled by the control unit C.
[0015]
Next, the operation control of the first and second solenoid valves 11 and 12 during normal braking and antilock brake control by the control unit C will be described. During normal braking, both the solenoid valves 11 and 12 are demagnetized by the control unit C. Thus, both solenoid valves 11 and 12 are in a hydraulic pressure state. Therefore, the hydraulic pressure output from the master cylinder 2 to the output hydraulic pressure path 4 by depressing the brake pedal 1 passes through the first orifice 19, the first electromagnetic valve 11, and the front wheel brake hydraulic pressure path 5, and the front wheel brake B _F And the braking force is exerted by the front wheel brake _BF . A second reflux path 16 that leads to the branch hydraulic pressure path 7 is connected to the output hydraulic pressure path 4 via the first reflux path 15, and a first check valve 17 is provided in the first reflux path 15. As a result, the hydraulic pressure in the output hydraulic pressure path 4 does not act on the branch hydraulic pressure path 7 via the first return path 15 and the second return path 16, and the hydraulic pressure in the front brake hydraulic pressure path 5 is the second pressure. branch passages 7 having a check valve 18 and the second orifice 20, acts on the rear wheel brake B _R via the second solenoid valve 12 and the rear wheel brake hydraulic pressure passage 6, the braking force at the rear wheel brake B _R is Demonstrated.
[0016]
At this time, the rear wheel brake B _F is of small compared to the front wheel brake B _R, the brake fluid pressure required in the rear wheel brake B _F also those lower than the front wheel brake B _F, output fluid the output pressure of the pressure passage 4, because they act on the constricted rear wheel brake B _R in two stages of the first and second orifices 19 and 20, the rear wheel brake B _R is boosted rapidly than necessary There is nothing.
[0017]
When the brake operation is stopped and the brake pedal 1 is returned, the brake fluid of the front wheel brake _BF is released to the master cylinder 2 through the second check valve 18 and the first check valve 17 with good responsiveness, After the brake pressure of the front wheel brake _BF decreases, the residual pressure is not generated in the front wheel brake _{BF by} being released to the master cylinder 2 via the first solenoid valve 11 and the first orifice 19. On the other hand, the brake fluid in the rear wheel brake B _R is relieved good response to the master cylinder 2 via the third check valve 21 and the first check valve 17, the brake pressure of the rear wheel brake B _R is reduced from it will be released to the master cylinder 2 via the second solenoid valve 12 and the first check valve 17, the rear wheel brake B _R by those that do not have a first check valve 17 spring There is no residual pressure.
[0018]
When performing antilock brake control during the brake operation, operation of the motor M i.e. pump P is started, when the vacuum wheel and the rear wheel brake B _F, the brake fluid pressure of B _R, the first and second solenoid valve 11 , 12 are excited. As a result, the first and second solenoid valves 11 and 12 are released from the hydraulic pressure, the front wheel brake hydraulic pressure passage 5 leads to the release passage 10 and the rear wheel brake hydraulic pressure passage 6 leads to the release passage 10. it is possible to depressurize the brake fluid pressure so as to release wheel brake B _F, the brake fluid pressure of B _R to the release passage 10.
[0019]
When the brake fluid pressure is maintained, as shown in FIG. 2, the operations of the first and second solenoid valves 11 and 12 are controlled so as to repeat the demagnetization / excitation, that is, the fluid pressure action state and the fluid pressure release state, in a short cycle. The As a result, the brake fluid pressure of the front wheel brake _BF is increased by the output fluid pressure of the master cylinder 2 when the first electromagnetic valve 11 is in the hydraulic pressure action state, and the release path when the first electromagnetic valve 11 is released. Repeat the hydraulic pressure release to 10 in a short period, also the brake fluid pressure of the rear wheel brake B _R is the pressure increase and the second solenoid valve according to the output pressure of the pump P in the liquid pressure acting state of the second solenoid valve 12 will be repeated hydraulic pressure release to release path 10 in the liquid pressure released state of 12 in a short period, the front and rear wheel brake B _F, the brake fluid pressure of B _R is artificially maintained.
[0020]
Reducing the pressure of the brake fluid pressure of the rear wheel brake B _R, when pressure increase the brake fluid pressure of the front wheel brake B _F, as shown in Figure 3, while the second solenoid valve 12 is the excitation state, the first The operation of the solenoid valve 11 is controlled so as to repeat the demagnetization and excitation, that is, the hydraulic pressure action state and the hydraulic pressure release state, by determining the ratio of the demagnetization time and the excitation time according to the pressure increasing speed. Thus, the brake fluid pressure for the rear wheel brake B _R will be vacuum gradually by hydraulic pressure release to release path 10. Further, the brake fluid pressure of the front wheel brake _BF is increased by the output fluid pressure of the master cylinder 2 when the first electromagnetic valve 11 is in the hydraulic pressure state, and the release path 10 when the first electromagnetic valve 11 is released. Repeat the decompression accompanying the release of the fluid pressure. At this time, the pump P is of small size, and since the brake fluid pressure from the rear wheel brake B _R is also in a state that the suction to release the brake fluid pressure of the front wheel brake hydraulic path 5 to the release path 10 Even so, the pressure reduction speed of the front wheel brake _BF is slower than the pressure increase speed due to the output hydraulic pressure of the master cylinder 2, and even if the demagnetization time of the first solenoid valve 11 is shorter than the excitation time, the front wheel The brake fluid pressure of the brake _BF is gradually increased.
[0021]
Reducing the pressure of the brake fluid pressure of the front wheel brake B _F, when pressure increase the brake fluid pressure of the rear wheel brake B _R, as shown in Figure 4, while the first solenoid valve 11 is the excitation state, the second The operation of the solenoid valve 12 is controlled so as to repeat the demagnetization and excitation, that is, the hydraulic pressure action state and the hydraulic pressure release state, by determining the ratio of the demagnetization time and the excitation time according to the pressure increasing speed. As a result, the brake fluid pressure of the front wheel brake _BF is gradually reduced by releasing the fluid pressure to the release path 10. The brake fluid pressure of the rear wheel brake B _R is the front wheel brake B _F the rear wheels is discharged by the pump P brake fluid released to the release path 10 in the liquid pressure acting state of the second solenoid valve 12 from the brake B _R Pressure increase due to acting on the pressure, and pressure reduction accompanying the release of the hydraulic pressure to the release path 10 in the hydraulic pressure release state of the second electromagnetic valve 12 are repeated, and the demagnetization time of the second electromagnetic valve 12 is determined from the excitation time. by also long, so that the brake fluid pressure of the rear wheel brake B _R is boosted gradually. In this case, the excitation time i.e. hydraulic released state of the second solenoid valve 12, since the brake fluid pressure of the rear wheel brake B _R is released to the release path 10, the brake fluid volume escaping to release path 10 from the front wheel brake B _F Is suppressed, and the pressure reduction speed of the front wheel brake _BF is temporarily reduced.
[0022]
Furthermore front and rear wheel brake B _F, when both cause boosted brake hydraulic pressure of the B _R, as shown in Figure 5, the demagnetization of the first and second solenoid valves 11, 12 and the excitation i.e. liquid pressure acting state and a liquid The operations of both solenoid valves 11 and 12 are controlled so that the pressure release state is in reverse phase, and the demagnetization time of the second solenoid valve 12 is set longer than the excitation time. Thus, the brake fluid pressure of the rear wheel brake B _R is boosted by exerting the rear wheel brake B _R by discharging brake fluid to be released to release path 10 from the front wheel brake B _F with the pump P, also the front wheels The brake fluid pressure of the brake _BF is increased by the output fluid pressure of the master cylinder 2.
[0023]
Next, to explain the action of this first embodiment, the pressure increase of the front wheel brake B _F when antilock brake control is mainly performed by the output hydraulic pressure of the master cylinder 2, also in the rear wheel brake B _R pressure increase is the pump P since it is made by the discharge pressure, pump P, as long as the front wheel brake small extent necessary to B than _F pressure increase the rear wheel brake B _R, which requires a small and low pressure of the brake pressure, and low discharge pressure Therefore, the pump P and the motor M can be reduced in size, and the entire antilock brake control device can be reduced in size and weight.
[0024]
Further, since the output hydraulic pressure of the master cylinder 2 is reduced in two stages of the first and second orifices 19 and 20 during normal braking, the first and second orifices 19 and 20 are reduced by one orifice. The degree of squeezing can be set to be smaller than that of the above-described one, and it is possible to avoid as much as possible that clogging of chips and brake fluid in the manufacturing process from each orifice 19, 20, a filter, etc. The orifices 19 and 20 can be easily managed.
[0025]
In addition, the degree of restriction of the first orifice 19 is smaller than the degree of restriction of the second orifice 20, and a sufficiently high brake fluid pressure can be applied to the front wheel brake _BF that requires a relatively high pressure.
[0026]
FIG. 6 shows a second embodiment of the present invention, and parts corresponding to the first embodiment are given the same reference numerals.
[0027]
A first hydraulic pressure control valve means 24 provided between the front wheel brake hydraulic pressure path 5 and the output hydraulic pressure path 4 and the release path 10 is normally provided between the front wheel brake hydraulic pressure path 5 and the output hydraulic pressure path 4. The open type electromagnetic valve 25 and a normally closed type electromagnetic valve 26 provided between the front wheel brake hydraulic pressure path 5 and the release path 10 are configured. The rear wheel brake hydraulic pressure path 6, the branch hydraulic pressure path 7 and the release path 10 are configured. A second hydraulic pressure control valve means 27 provided between them is a normally open electromagnetic valve 28 provided between the rear wheel brake hydraulic pressure path 6 and the branch hydraulic pressure path 7, and the rear wheel brake hydraulic pressure path 6 and the release path 10. It comprises a normally closed electromagnetic valve 29 provided between them.
[0028]
According to the second embodiment, the same effect as that of the first embodiment can be obtained.
[0029]
Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above-described embodiments, and various design changes can be made without departing from the present invention described in the claims. Is possible.
[0030]
For example, in the above embodiment, when the brake fluid pressures of the front and rear wheel brakes B _F and B _R are both increased, the hydraulic pressure action state and the hydraulic pressure release state of the first and second hydraulic pressure control valve means are reversed. It has been controlled to a phase, as long as the brake fluid release path 10 to the pressure increase in the rear wheel brake B _R can be supplied to the pumping Gaité rear wheel brake B _R by the pump P, the first and second liquid It is allowed that the hydraulic pressure action state and the hydraulic pressure release state of the pressure control valve means are not completely opposite to each other but slightly shifted in opposite phases. The may also be reservoir release passage 10 is connected, if so, the front wheel and the rear wheel brake B _F, the first and second pressure control valve means when the pressure both increasing the brake fluid pressure of B _R displacement of the liquid pressure acting state and the hydraulic released state when the opposite phase becomes possible pressure increase the brake fluid pressure of the rear wheel brake B _R be relatively large.
[0031]
【The invention's effect】
As described above, according to the present invention, the brake fluid pressure of the front wheel brake is mainly increased by the output fluid pressure of the master cylinder, and the brake fluid pressure of the rear wheel brake is increased by the pump discharge fluid pressure, The capacity and discharge pressure of the pump can be set to such an extent that the brake fluid pressure of the rear wheel brake can be increased, and the pump and the motor that drives the pump are reduced in size so that the entire anti-lock brake control device is reduced in size It is possible to reduce the weight.
[Brief description of the drawings]
FIG. 1 is a circuit diagram showing a configuration of a vehicle antilock brake control device according to a first embodiment;
FIG. 2 is a diagram showing the operation timing of both solenoid valves and the change in brake pressure when the brake pressure is maintained, corresponding to each other.
FIG. 3 is a diagram showing the operation timing of both solenoid valves and the change in brake pressure when the front wheel brake pressure is increased and the rear wheel brake pressure is decreased.
FIG. 4 is a diagram showing the operation timing of both solenoid valves and the change in brake pressure when the front wheel brake pressure is reduced and the rear wheel brake pressure is increased.
FIG. 5 is a diagram showing the operation timing of both solenoid valves and the change in brake pressure when pressure is increased in both front and rear wheel brakes.
FIG. 6 is a circuit diagram showing a configuration of a vehicle antilock brake control device according to a second embodiment;
[Explanation of symbols]
2 ... Master cylinder 4 ... Output hydraulic pressure path 5 ... Front wheel brake hydraulic pressure path 6 ... Rear wheel brake hydraulic pressure path 7 ... Branch hydraulic pressure path 8 ... Suction port 10 ... Release path 11: first solenoid valve 12 as first fluid pressure control piece means ... second solenoid valve 15 as second fluid pressure control valve means ... first return path 16 ... first 2 recirculation path 17 ... 1st check valve 18 ... 2nd check valve 24 ... 1st hydraulic pressure control valve means 27 ... 2nd hydraulic pressure control valve means _BF ... Front wheel brake B _R · · · rear wheel brake C · · · control unit P · · · pump

Claims (1)

Output hydraulic pressure path (4) leading to the output port (3) of the master cylinder (2); Front wheel brake hydraulic pressure path (5) leading to the front wheel brake (B _F ); After leading to the rear wheel brake (B _R ) Wheel brake hydraulic pressure path (6); Branch hydraulic pressure path (7) branched from front wheel brake hydraulic pressure path (5); Brake hydraulic pressure released from front wheel and rear wheel brakes (B _F , B _R ) A release path (10) capable of guiding the same in common; a pump (P) in which the release path (10) is connected to the suction port (8); a front-wheel brake hydraulic pressure path (5) through an output hydraulic pressure path (4) The hydraulic pressure release state is connected to the release passage (10) but is disconnected from the release passage (10), and the hydraulic pressure is released from the front wheel brake hydraulic passage (5) to the release passage (10) but from the output hydraulic passage (4). The state can be switched between the front wheel brake hydraulic pressure path (5), the output hydraulic pressure path (4), and the release path (10). A first hydraulic pressure control valve means (11, 24) provided therebetween; a hydraulic pressure that allows the rear wheel brake hydraulic pressure passage (6) to communicate with the branch hydraulic pressure passage (7) but is disconnected from the release passage (10). The rear wheel brake hydraulic pressure path (6) can be switched between an operating state and a hydraulic pressure release state that allows the rear wheel brake hydraulic pressure path (6) to communicate with the release path (10) but is disconnected from the branch hydraulic pressure path (7). A second hydraulic pressure control valve means (12, 27) provided between the branch hydraulic pressure path (7) and the release path (10); a discharge port (13) of the pump (P) and an output hydraulic pressure path (4) A first return path (15) connecting between the first return path (15) and the first return path (15) allowing only the flow of brake fluid from the pump (P) to the output hydraulic pressure path (4) side. The first check valve (17); and only the flow of the brake fluid from the front wheel brake fluid pressure passage (5) to the rear wheel brake fluid pressure passage (6). A second check valve (18) provided in the branch hydraulic pressure path (7); a branch hydraulic pressure path between the second check valve (18) and the second hydraulic pressure control valve means (12, 27) (7) and the second recirculation path (16) connecting between the discharge port (13); and each operation of the first and second hydraulic pressure control valve means (11, 24; 12, 27) is controlled. And a control unit (C) for operating the pump (P) in the anti-lock brake control state.
When the control unit (C) increases the brake fluid pressure of the front and rear wheel brakes (B _F , B _R ) in the anti-lock brake control state, the control unit (C) first and second hydraulic control valve means (11, characterized in that that controls the operation of the 12, 27); 24; 12, 27) of the liquid pressure acting state and Ryoeki pressure control valve means so that fluid pressure released state is substantially opposite phase (11, 24 Anti-lock brake control device for vehicles.

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