JPH11115715A - Brake hydraulic control device for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sufficient brake force without interrupting the brake hydraulic pressure control of a driving wheel brake after eliminating means to detect brake operation when a brake is operated under a condition that the driving wheel brake is operated during the brake is not operated. SOLUTION: In this brake hydraulic control device for a vehicle, first hydraulic pressure passages 4A, 4B normally communicated with a master cylinder M are connected to driven wheel brakes BRR, BRL through normally opened type solenoid valves 7A, 7B for driven wheels, second hydraulic pressure passages 12A, 12B which are disconnected from the master cylinder M according to control of hydraulic pressure in a control pressure chamber by control pressure controlling means 44A, 44B and also can obtain hydraulic pressure in compliance with the hydraulic pressure in the control pressure chamber, are connected to driving wheel brakes BFL, BFR through normally owning type solenoid valves 14A, 14B for driving wheels, and the control pressure chamber is connected to a second reservoir 43 through relieve valves 48A, 48B.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressure adjusting means for a driven wheel brake capable of adjusting a brake fluid pressure of a driven wheel brake, and a pressure adjusting means for a drive wheel brake capable of adjusting a brake fluid pressure of a driven wheel brake. A pressurizing pump that discharges when the drive wheel brake is operated at least in a non-braking operation state, and a control pressure chamber and a pressurizing chamber connected to a discharge port of the pressurizing pump, both ends of which are exposed and pressurized. A pressurizing piston which is slidably fitted to the housing by being spring-biased to the side which increases the volume of the chamber, and a side which is provided between the master cylinder and the pressurizing chamber and reduces the volume of the pressurizing chamber. And a cut valve operable to close the valve in response to the movement of the pressurizing piston to the vehicle, and to a brake fluid pressure control device for a vehicle capable of applying brake fluid pressure in the pressurizing chamber to drive wheel brakes.

[0002]

2. Description of the Related Art Conventionally, such a brake fluid pressure control device has
For example, Japanese Utility Model Laid-Open No. 5-84551 and Japanese Unexamined Patent Publication No.
It is already known from, for example, US Pat.

[0003]

However, in the prior art, the pressure adjusting means for the driven wheel brake and the pressure adjusting means for the drive wheel brake are commonly connected to the pressurizing chamber, so that the driving wheel is not operated when the brake is not operated. When executing traction control that exerts the braking force with the brake,
The cut valve is closed by the movement of the pressurizing piston, and the brake fluid pressure increased as the volume of the pressurizing chamber is reduced acts on the driven wheel and the drive wheel brake pressure-adjusting means, respectively. The brake pressure adjusting means is in a state of disconnecting the space between the pressurizing chamber and the driven wheel brake. Therefore, even if the brake operation is performed during the traction control, the output hydraulic pressure of the master cylinder does not act on the driven wheel brake, and only the cut valve is opened by overcoming the hydraulic pressure of the control pressure chamber. Even if the brake operation is performed strongly so that the hydraulic pressure is output from the master cylinder, the pressure adjusting means for the drive wheel brakes maintains and reduces the brake fluid pressure of the drive wheel brake by applying a pressure between the pressurizing chamber and the drive wheel brake. , The brake pressure associated with the brake operation does not act on the drive wheel brakes. Therefore, even if the brake operation is performed during the traction control, a sufficient braking force cannot be obtained.

Therefore, it is conceivable to open the cut valve in accordance with the brake operation during execution of the traction control, and to operate the pressure adjusting means for the driven wheel brake so as to communicate between the pressurizing chamber and the driven wheel brake. However, a switch or a sensor for detecting a brake operation is required, and traction control is interrupted.

Japanese Patent Application Laid-Open No. 6-1226 discloses a check valve that opens in accordance with the output hydraulic pressure of a master cylinder to release the hydraulic pressure in the control pressure chamber to a reservoir. The configuration provided in is also disclosed,
According to such a configuration, the means for detecting the brake operation is not required, and the cut valve can be opened according to the brake operation during the traction control, but also in this case, the traction control is interrupted. I will.

The present invention has been made in view of the above circumstances, and eliminates the need for a means for detecting a brake operation during a brake operation in a state where the drive wheel brake is operated during a non-brake operation. It is an object of the present invention to provide a vehicle brake fluid pressure control device capable of obtaining a sufficient braking force without interrupting brake fluid pressure control of a wheel brake.

[0007]

SUMMARY OF THE INVENTION In order to achieve the above object, the invention according to claim 1 comprises a pressure adjusting means for a driven wheel brake capable of adjusting a brake fluid pressure of a driven wheel brake, and a brake for a drive wheel brake. Pressure adjusting means for a drive wheel brake capable of adjusting a hydraulic pressure, a pressurizing pump which discharges when at least a brake is applied to the drive wheel brake in a non-braking operation state, and a control connected to a discharge port of the pressurizing pump A pressurizing piston which is slidably fitted to the housing by being spring-biased to the pressure chamber and the pressurizing chamber with both ends facing and increasing the volume of the pressurizing chamber, and between the master cylinder and the pressurizing chamber. And a cut valve that closes in response to the movement of the pressurizing piston to the side that reduces the volume of the pressurizing chamber, so that the brake fluid pressure in the pressurizing chamber can act on the drive wheel brake. car In the brake fluid pressure control apparatus,
A control pressure control means for controlling a control pressure in the control pressure chamber by controlling a control pressure action from the pressurizing pump to the control pressure chamber and a control pressure release from the control pressure chamber; Has a normally-open solenoid valve for driven wheels that is provided between the first hydraulic pressure path and the driven wheel brake that always communicates with the master cylinder, and that can be closed only during anti-lock brake control of the driven wheel brakes. The drive wheel brake pressure adjusting means is provided between the second hydraulic pressure path and the drive wheel brake which are always in communication with the pressurizing chamber. A normally open solenoid valve for driving wheels that can be closed only during antilock brake control, a first reservoir,
A normally-closed solenoid valve provided between the drive wheel brake and the first reservoir, and a common motor for driving the brake fluid pressure of the drive wheel brakes regardless of whether the brake is operated or not operated. And a return pump capable of supplying the brake fluid of the first reservoir to the second hydraulic path, wherein the control pressure chamber is connected to the second reservoir via a relief valve.

According to such a configuration, when the drive wheel brake is operated during the non-braking operation,
By controlling the discharge pressure of the pressurizing pump that performs discharge by the control pressure control means to act on the control pressure chamber, the pressurizing piston moves, the cut valve closes, and the pressure increases as the volume of the pressurizing chamber decreases. The applied brake fluid pressure is output to the second fluid pressure passage. At this time, the normally-open solenoid valve for the driven wheel and the normally-open solenoid valve for the drive wheel are in the open state, and the hydraulic pressure in the pressurizing chamber according to the control pressure in the control pressure chamber acts on the drive wheel brake. That is, the brake of the drive wheel brake can be operated during the non-brake operation. When a brake operation is performed in such a driving wheel brake operating state at the time of the non-braking operation, the hydraulic pressure output from the master cylinder is transmitted from the first hydraulic pressure path via the normally-open solenoid valve for a driven wheel that is opened. Acting on the driven wheel brake side, the braking force corresponding to the brake operation can be exerted by the driven wheel brake.
Also, when a strong brake operation is performed so that the hydraulic pressure in the control pressure chamber overcomes the hydraulic pressure of the control pressure chamber to open the cut valve and the master cylinder outputs the hydraulic pressure, the output hydraulic pressure of the master cylinder is reduced to the second hydraulic pressure path. Can act on the drive wheel brake through the normally open solenoid valve for the drive wheel in the open state from
Therefore, even when the driving wheel brake is operated during the non-braking operation, a sufficient braking force accompanying the braking operation can be obtained, and a means for detecting the braking operation during such a braking operation is unnecessary. ,
The brake pressure control of the drive wheel brake is not interrupted by the brake operation. In addition, since the control pressure of the control pressure chamber is controlled by the control pressure control means, the control pressure chamber may be in a closed state, in which case, the anti-lock brake control of the drive wheel brake is performed. When the normally open solenoid valve for drive wheels is closed, the output of the return pump increases the hydraulic pressure in the pressurizing chamber, and the pressurizing piston may be pushed back to the control pressure chamber side. Although there is a possibility that the control pressure chamber is in an abnormally high pressure state, the control pressure chamber is not in an abnormally high pressure state because the relief valve is connected to the control pressure chamber.

According to a second aspect of the present invention, in addition to the configuration of the first aspect of the present invention, the control pressure control means is provided between the pressurizing pump and the control pressure chamber, and between the control pressure chamber and the second reservoir. Even though the pressurizing pump driven by the common motor with the return pump is operated by the anti-lock brake control at the time of the brake operation by being constituted by the normally-open type solenoid valve provided between them, Since the two normally open solenoid valves constituting the control pressure control means are in the open state, the load on the motor can be reduced.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The embodiments of the present invention will be described below based on one embodiment of the present invention shown in the accompanying drawings.

FIGS. 1 and 2 show an embodiment of the present invention. FIG. 1 is a view showing a configuration of a brake fluid pressure control device, and FIG. 2 is a longitudinal sectional view showing a configuration of a control actuator.

First, in FIG. 1, left and right driving wheel brakes B _FL and B _FL are provided on left and right front wheels which are driving wheels in a front wheel driving vehicle.
_FR is mounted, and left and right driven wheel brakes B _RL and B _RR are mounted on the left and right rear wheels, and the wheel brakes B _FL , B _FR , B _RL and B _RR are, for example, disc brakes. It is.

A pair of output ports 2A and 2B provided in a tandem type master cylinder M provided with a reservoir R outputs a brake fluid pressure corresponding to the depression operation of the brake pedal 3, and one of the output ports 2A is connected to one output port 2A. Is connected to the first hydraulic pressure passage 4A, and the other output port 2B is connected to the first hydraulic pressure passage 4B. Thus, one first hydraulic passage 4
A is connected to the right driven wheel brake B _RR via the driven wheel brake pressure regulating means 5A and the proportional pressure reducing valve 6A, other first fluid pressure passage 4B are tuning driven wheel brake pressure means 5B and proportional pressure reducing It is connected to the left driven wheel brake B _RL via a valve 6B.

The driven wheel brake pressure adjusting means 5A corresponding to the right driven wheel brake B _RR includes a driven wheel normally open solenoid valve 7A provided between the first hydraulic pressure path 4A and the proportional pressure reducing valve 6A.
The normally closed solenoid valve 8A for the driven wheel provided between the first reservoir 10A different from the reservoir R attached to the master cylinder M and the proportional pressure reducing valve 6A, and the first hydraulic pressure passage 4A from the proportional pressure reducing valve 6A side. Check valve 9 connected in parallel to the normally open solenoid valve 7A for the driven wheel while allowing the brake fluid to flow to the side
A.

Further left driven wheel brake B _RL driven wheel brake pressure regulating means 5B corresponding to the first fluid pressure passage 4B and the proportional pressure reducing valve 6B normally open electromagnetic valve driven wheel is provided between 7B
A normally closed solenoid valve 8B for a driven wheel provided between a first reservoir 10B different from the reservoir R attached to the master cylinder M and the proportional pressure reducing valve 6B, and a first hydraulic pressure from the proportional pressure reducing valve 6B side. A check valve 9B is connected in parallel to the normally open solenoid valve 7B for the driven wheel while allowing the flow of the brake fluid to the road 4B side.

In addition, normally-open solenoid valves 7A, 7B for driven wheels
Can be closed only during the anti-lock brake control of the driven wheel brakes B _RR and B _RL. The normally closed solenoid valves 8A and 8B for the driven wheel can be closed by the anti-lock brake control of the driven wheel brakes B _RR and B _RL. The valve can be opened only at the time.

Such pressure adjusting means 5 for driven wheel brakes
According to A and 5B, when the brake pedal is depressed, the normally closed solenoid valves 8A and 8B for the driven wheels are operated.
When the solenoid valves 7A and 7B for the driven wheels are opened when the valve is closed, the hydraulic pressure of each output port 2A and 2B is reduced by the proportional pressure reducing valves 6A and 6B, and the driven wheel brakes B _RR and B B _RL
And the normally open solenoid valve 7 for the driven wheel.
When both A and 7B and the normally closed solenoid valves 8A and 8B for the driven wheels are closed, the brake fluid pressure of the driven wheel brakes B _RR and B _RL can be maintained, and the normally opened solenoid valves for the driven wheels 7
Normally closed solenoid valves 8A, 8 for driven wheels with A, 7B closed
By opening B, the brake fluid pressure of the driven wheel brakes B _RR and B _RL can be reduced.

The first hydraulic passages 4A and 4B are connected to the second hydraulic passage 12 via control actuators 11A and 11B, respectively.
A, 12B are individually connected to each other, and each of the second hydraulic pressure paths 12A, 12B is
A and 13B are respectively connected to left and right drive wheel brakes B _FL and B _FR .

The driving wheel brake pressure adjusting means 13A corresponding to the left driving wheel brake B _FL includes a first reservoir 10A which is common to the driven wheel brake pressure adjusting means 5A, a second hydraulic pressure passage 12A and a left driving means. A normally open solenoid valve for drive wheels 14A provided between the wheel brakes B _FL and the first reservoir 10A
A normally closed solenoid valve for driving wheels 15A provided between the left driving wheel brake _BFL and a left driving wheel brake BFL; a return pump 16A capable of pumping brake fluid from the first reservoir 10A;
A and a return pump 1 connected to the discharge port of the pump A
A throttle 18A provided between the discharge port 6A and the second hydraulic passage 12A, and a second hydraulic passage 1 from the left drive wheel brake _BFL side.
A check valve 19A is connected in parallel with the normally open solenoid valve for drive wheel 14A to allow the flow of brake fluid to the 2A side. The normally open solenoid valve for drive wheel 14A is connected to the drive wheel brake B _FL. when the anti-lock brake control only are those capable of closing, drive wheel normally closed solenoid valve 15A is capable opened only when antilock brake control of the drive wheel brake B _FL.

Such drive wheel brake pressure adjusting means 13A
According to the above, when the brake operation is performed by depressing the brake pedal 3 when the first output port 2A of the master cylinder M is in communication with the second hydraulic path 12A, the output hydraulic pressure of the first output port 2A is reduced. It can be applied to the left driving wheel brake B _FL, and at the time of brake pressure adjustment when the left front wheel is about to enter a locked state during such a brake operation,
When the return pump 16A is operated, the normally open solenoid valve 14A for the drive wheel is closed and the normally closed solenoid valve 15A for the drive wheel is opened, so that the left drive wheel brake B
A part of the brake fluid pressure of the _FL is released to the first reservoir 10A and the pressure is reduced. When the brake fluid pressure is maintained, the normally open solenoid valve 14A for drive wheels and the normally closed solenoid valve 15A for drive wheels may be maintained in the closed state. When increasing the brake fluid pressure, Normally open solenoid valve for drive wheels 14
A may be opened and the normally closed solenoid valve for drive wheels 15A may be closed.

The brake fluid released to the first reservoir 10A is returned from the return pump 16A to the upstream side of the drive wheel normally open solenoid valve 14A via the damper 17A and the throttle 18A. Therefore, the depression amount of the brake pedal 3 in the master cylinder M does not increase by the amount released to the first reservoir 10A, and the pulsation of the brake fluid sent from the return pump 16A is attenuated by the functions of the damper 17A and the throttle 18A. , The brake pedal 3
No pulsation is transmitted to

The drive wheel brake pressure adjusting means 13B corresponding to the right drive wheel brake B _FR is provided with a driven wheel brake pressure adjuster 5B in the same manner as the above-mentioned right drive wheel brake pressure adjuster 13A.
Between and the first reservoir 10B common, and the second liquid pressure passage 12B and the right drive wheel brake B _FR normally open electromagnetic valve drive wheels provided between 14B, the first reservoir 10B and the right drive wheel brake B _RL Normally closed solenoid valve 1 for drive wheels
5B, a return pump 16B capable of pumping the brake fluid of the first reservoir 10B, a damper 17B connected to a discharge port of the return pump 16B, and a discharge port of the return pump 16B and the second hydraulic path 12B. An aperture 18B provided;
Right drive wheel brake B Normally open type solenoid valve 14B for drive wheels by allowing the flow of brake fluid from _FR side to second hydraulic path 12B side.
The return pump 16B is driven by a motor 20 common to the return pump 16A of the driving wheel brake pressure adjusting means 13A on the left driving wheel brake _BFL side.

In FIG. 2, the control actuator 11A
A pressurizing chamber 24 is formed between a housing 23 having an input port 22 at one end wall communicating with the first hydraulic pressure passage 4A on one end wall, and a control pressure between the housing 23 and the other end wall. A pressurizing piston 26 which forms a chamber 25 and is slidably fitted to the housing 23; a return spring 27 which exerts a spring force in a direction to reduce the volume of the control pressure chamber 25; The valve closing operation is performed in response to the movement of the pressurizing piston 26 to the side of reducing the volume, and the input port 22 and the pressurizing chamber 24 are operated.
And a cut valve 28 for shutting off the air pressure, and an output port 29 communicating with the second hydraulic pressure passage 12A is provided on a side portion of the housing 23.
Is provided so as to always communicate with the pressure chamber 24 regardless of the axial position of the pressure piston 26.

The housing 23 comprises a housing main body 30 having a bottomed storage hole 32 with one end closed, and a bottomed cylindrical body 31 fitted and fixed to the other end opening of the storage hole 32. The input port 22 is opened at the center of one end of the storage hole 32 so that the housing main body 30 is closed.
The pressurizing piston 26 is slidably fitted to the housing main body 30 and the bottomed cylindrical body 31 so as to form the control pressure chamber 25 with the closed end of the bottomed cylindrical body 31. .

The cut valve 28 is formed in a cap shape having a flange portion 33 a in contact with one end wall of the housing 23 on the open end side, and is housed in the pressurizing chamber 24.
And the valve body 34 housed in the valve box 33 so that the input port 22 can be closed, and the valve body 34 is housed in the valve box 33 by exerting a spring force for urging the valve body 34 in a direction to close the input port 22. And a spring force of the valve spring 35 is set smaller than a spring force of the return spring 27.

The valve element 34 is provided at one end of a stem 36 which is coaxial with the pressurizing piston 26.
Movably penetrates a through hole 37 provided in the valve box 33. Thus, the valve spring 35 includes the stem 36 and the valve housing 33.
It is provided between them.

On the other hand, the enlarged diameter portion 36a provided at the other end of the stem 36 is inserted into a bottomed guide hole 38 provided in the pressurizing piston 26 so as to open to the pressurizing chamber 24 side. The closed end of the guide hole 38 and the space between the stem 36 are added between the inner surface of the guide hole 38 and the outer surface of the enlarged diameter portion 36 a in accordance with the axial movement of the stem 36 relative to the pressurizing piston 26. A gap is formed so that the pressure is not reduced. On the surface of the pressure piston 26 facing the pressure chamber 24, a ring-shaped regulating plate 39 capable of engaging the inner peripheral edge with the enlarged diameter portion 36a of the stem 36 is fixed by caulking. The coil-shaped return spring 27 is provided between the valve housing 33 and the flange portion 33a. Due to the spring force of the return spring 27, the pressurizing piston 26 is urged to reduce the volume of the pressurizing chamber 24, the regulating plate 39 is substantially fixed to the pressurizing piston 26, and the valve box 33 is moved. It is substantially fixed to one end wall of the housing 23. The valve box 33 has a plurality of communication holes 40 through which the inside of the valve box 33 communicates with the pressurizing chamber 24.
... are provided.

According to the control actuator 11A, the pressurizing piston 26 operates in the axial direction according to the control of the hydraulic pressure in the control pressure chamber 25, and the pressurizing piston 26 reduces the volume of the pressurizing chamber 24. When you move forward in the direction of reduction,
The regulation of the stem 36 by the regulating plate 39 is released, and the stem 36, that is, the valve body 34 is operated forward, whereby the cut valve 28 is closed so that the input port 22 is closed, and the input port 22 and the pressurizing chamber are closed. 24, that is, between the first hydraulic pressure passage 4A and the second hydraulic pressure passage 12A connected to the first output port 2A of the master cylinder M. Further, the hydraulic pressure in the pressurizing chamber 24 increases in accordance with the volume reduction of the pressurizing chamber 24 by the pressurizing piston 26, and the increased hydraulic pressure acts on the second hydraulic pressure passage 12A.

The hydraulic pressure in the control pressure chamber 25 is controlled by the control pressure control means 4 from the pressurizing pump 42 to the control pressure chamber 25 and the control pressure release from the control pressure chamber 25 to the second reservoir 43.
4A, and is controlled by adjusting the pressure with the pressure adjusting means 4A.
B is driven by a common motor 20 with the return pumps 16A and 16B of B. The motor 20 controls the brake fluid pressure of the driving wheel brakes B _FL and B _FR regardless of the brake operation and the non-brake operation. Is controlled to operate. The second reservoir 43 is independent of the reservoir R attached to the master cylinder M and the first reservoirs 10A and 10B. Further, a pressure regulating valve 47 is provided between the discharge port of the pressure pump 42 and the second reservoir 43, and the discharge pressure of the pressure pump 42 is regulated by the pressure regulating valve 47 to be substantially constant.

The control pressure control means 44 A
Of the control pressure chamber 2 of the discharge port and the control actuator 11A
5 and a normally open solenoid valve 46A provided between the control pressure chamber 25 and the second reservoir 43, and the control pressure chamber 25 of the control actuator 11A. Is connected to the second reservoir 43 via a relief valve 48A.

The first hydraulic passage 4B and the second hydraulic passage 12
The control actuator 11B provided between B and B is configured similarly to the control actuator 11A, and the control pressure control means 44B for controlling the control pressure of the control actuator 11B is controlled similarly to the control pressure control means 44A. A normally open solenoid valve 45B provided between a control pressure chamber (not shown) of the actuator 11B and the pressurizing pump 42;
It comprises a control pressure chamber of the control actuator 11B and a normally open solenoid valve 46B provided between the second reservoir 43. The control pressure chamber of the control actuator 11B is connected to the second reservoir 43 via a relief valve 48B.

Next, the operation of this embodiment will be described.
And drive wheel brake B during non-brake operation_FL, B_FRThe
When the rake is activated, the discharge pressure of the pressure pump 42
Is controlled by the control pressure control means 44A, 44B to control the control.
Act on the control pressure chamber 25 of the heaters 11A and 11B.
You. Then, the control actuators 11A and 11B
Pressurizing piston 26 reduces the volume of pressurizing chamber 24
Direction, the cut valve 28 closes and the pressurizing chamber
The brake fluid pressure increased due to the volume decrease
It is output to the hydraulic passages 12A and 12B. At this time, for the driven wheel
Normally Open Type Solenoid Valves 7A and 7B and Normally Open Type Solenoid Valve 1 for Drive Wheels
4A and 14B are in a valve-open state while being demagnetized.
The hydraulic pressure of the pressurizing chamber 24 is driven according to the control pressure of the control pressure chamber 25
Wheel brake B _FL, B_FRNon-breaking
Drive wheel brake B during key operation_FL, B_FRActivate the brake
Can be closed. Thus, the drive wheels during non-brake operation
Braking is used to eliminate excessive slip of the drive wheels
For traction control and vehicle behavior stabilization control.
It is something to be done.

As described above, when the brake operation is performed by depressing the brake pedal 3 during the brake operation of the drive wheel brakes B _FL and B _FR in the non-brake operation state, the master cylinder M moves to the first hydraulic pressure passages 4A and 4B. The output hydraulic pressure is
The brakes act on the driven wheel brakes B _RR and B _RL via the normally-open solenoid valves 7A and 7B for the driven wheels in the opened state, and apply the braking force according to the brake operation to the driven wheel brakes B _RR and B _RR .
It can be demonstrated with _RL .

When the brake operation is performed so strongly that the master cylinder M outputs a hydraulic pressure sufficient to open the cut valve 28 by overcoming the hydraulic pressure in the control pressure chamber 25, the output hydraulic pressure of the master cylinder M To the second hydraulic passage 12
A, 12B normally open solenoid valve 14 for the drive wheels in the open state
A, 14B and through the driving wheel brake B _FL, B can be allowed to act on the _FR, thus even when the drive wheel brake B _FL during non brake operation, the B _FR are allowed braking, accompanied sufficient braking operation A good braking force can be obtained. Further, at the time of such a brake operation, means for detecting the brake operation is unnecessary, and the brake fluid pressure control of the drive wheel brakes B _FL and B _FR is not interrupted by the brake operation.

Incidentally, the control actuators 11A, 1
The control pressure of the control pressure chamber 25 in 1B is controlled by the control pressure control means 4
Since control is performed by 4A and 44B, the control pressure chamber 25 may be in a closed state. That is, the anti-lock brake control of the drive wheel brakes B _FL and B _FR during the traction control, or the drive wheel brakes B _FL and B B during the behavior stabilization control.
_{When the normally} open solenoid valves 14A and 14B for the drive wheels are closed to execute the anti-lock brake control of the _FR ,
The output of the return pumps 16A and 16B may increase the fluid pressure in the pressurizing chamber 24 and push the pressurizing piston 26 back to the control pressure chamber 25, thereby causing the control pressure chamber 25 to be in an abnormally high pressure state. There is. However, since the relief valves 48A and 48B are connected to the control pressure chamber 25, the control pressure chamber 25 does not enter an abnormally high pressure state.

Further, the control pressure control means 44A, 44B
Normally-open solenoid valves 45A, 45B; 46A, 46B provided between the pressurizing pump 42 and the control pressure chamber 25 and between the control pressure chamber 25 and the second reservoir 43, respectively. The return pumps 16A, 16B The normally open solenoid valves 45A, 45B; 46A, 4 despite the fact that the pressurizing pump 42 driven by the common motor 20 performs the discharge operation also during the antilock brake control during the brake operation.
Since the valve 6B is open, the load on the motor 20 can be reduced.

Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above embodiments, and various design changes can be made without departing from the present invention described in the appended claims. It is possible to do.

[0038]

As described above, according to the first aspect of the present invention, the hydraulic pressure output from the master cylinder is applied to the driven wheels during the braking operation in a state where the driving wheel brake is operated during the non-braking operation. When the brake operation can be applied to the brake side and the brake pressure is strong enough to open the cut valve from the master cylinder, the output hydraulic pressure of the master cylinder should be applied to the drive wheel brake. A sufficient braking force can be obtained, and a means for detecting the brake operation during such a brake operation is unnecessary, and the brake fluid pressure control of the drive wheel brake is not interrupted by the brake operation. . In addition, the control pressure chamber can be prevented from being in an abnormally high pressure state.

According to the second aspect of the invention, the load on the motor can be reduced during the antilock brake control during the brake operation.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a brake fluid pressure control device.

FIG. 2 is a longitudinal sectional view showing a configuration of a control actuator.

[Explanation of symbols]

4A, 4B: first hydraulic pressure path 5A, 5B: pressure adjusting means for driven wheel brake 7A, 7B: normally open solenoid valve for driven wheel 10A, 10B: first reservoir 12A, 12B ··· Second hydraulic pressure path 13A, 13B ··· Pressure regulating means for driving wheel brakes 14A, 14B ··· Normally open solenoid valve for driving wheel 15A, 15B ··· Normally closed solenoid valve 16A, 16B ..Return pump 20 ... Motor 23 ... Housing 24 ... Pressure chamber 25 ... Control pressure chamber 26 ... Pressurizing piston 28 ... Cut valve 42 ... Pressure pump 43 ..Second reservoirs 44A, 44B: control pressure control means 48A, 48B: relief valves 45A, 45B, 46A, 46B: normally open solenoid valves B _FL , B _FR: drive wheel brakes B _RL, B _RR ··· driven wheel brake M ··· Masutashi Sunda

Claims (2)

[Claims] A pressure adjusting means for a driven wheel brake capable of adjusting a brake fluid pressure of a driven wheel brake (B _RR , B _RL ).
5B) and drive wheel brake pressure adjusting means (13A, 1) capable of adjusting the brake fluid pressure of the drive wheel brakes (B _FL , B _FR ).
3B), a pressurizing pump (42) that discharges when the drive wheel brakes (B _FL , B _FR ) are braked at least in a non-braking operation state, and the pressurizing pump (42)
Both ends of the control pressure chamber (25) and the pressurizing chamber (24) connected to the discharge port of the pressure chamber are exposed, and the spring is biased toward the side that increases the volume of the pressurizing chamber (24) and slides on the housing (23). A pressurizing piston (26), which is movably fitted, is provided between the master cylinder (M) and the pressurizing chamber (24), and is pressurized to a side that reduces the volume of the pressurizing chamber (24). A cut valve (28) that operates to close in response to the movement of the piston (26), and that the brake fluid pressure in the pressurizing chamber (24) can act on the drive wheel brakes (B _FL , B _FR ). In the brake fluid pressure control device, the pressure pump (4
The control pressure action from the control pressure chamber (25) to the control pressure chamber (25) and the control pressure release from the control pressure chamber (25) are adjusted to control the control pressure chamber (2).
Control pressure control means (44A, 44A) for controlling the control pressure of 5)
B) and the pressure adjusting means for driven wheel brakes (5A, 5A).
B) is a first hydraulic pressure path (4A, 4B) which always communicates with the master cylinder (M) and a driven wheel brake (B _RR ,
B _RL ) and a driven wheel brake (B _RR ,
Adjusting the brake fluid pressure of the driven wheel brake (B _RR, B _RL) have B _RL) of the anti-lock brake control during only driven wheel normally open electromagnetic valve capable of closing the (7A, 7B) The driving wheel brake pressure adjusting means (13
A, 13B) is a second communication which is always in communication with the pressure chamber (24).
A drive wheel that is provided between the hydraulic pressure paths (12A, 12B) and the drive wheel brakes (B _FL , B _FR ) and that can be closed only during anti-lock brake control of the drive wheel brakes (B _FL , B _FR ) Normally open solenoid valve (14A, 14
B), the first reservoirs (10A, 10B), the drive wheel brakes (B _FL , B _FR ) and the first reservoirs (10A, 1B).
0B) Normally closed solenoid valve (15A, 15B)
When controlling the brake fluid pressure of the drive wheel brakes (B _FL , B _FR ) irrespective of the brake operation and the non-brake operation, a motor (2) common to the pressure pump (42) is used.
0) and return pumps (16A, 16B) capable of supplying the brake fluid of the first reservoirs (10A, 10B) to the second hydraulic pressure paths (12A, 12B), and the control pressure chamber (25). Is the second through the relief valve (48A, 48B)
A brake fluid pressure control device for a vehicle, which is connected to a reservoir (43). 2. The control pressure control means (44A, 44B).
Are normally open solenoid valves (45A, 45B; 4) provided between the pressurizing pump (42) and the control pressure chamber (25) and between the control pressure chamber (25) and the second reservoir (43), respectively.
6A, 46B).
6. A brake fluid pressure control device for a vehicle according to claim 1.