JPH09309427A - Brake device for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent an excessive increase of the brake liquid pressure as well as to increase the brake liquid pressure generated by a specific brake liquid pressure generating source so as to secure a high braking force, in the braking time of a vehicle. SOLUTION: A relative pressure releif valve 17 is provided in parallel to a pump 15. When the brake liquid pressure in a pipe line between a proportional control valve 13 and the pump 15 is made larger a-specific value than the brake liquid pressure in a pipe line between a reservoir 20 and the pump 15, that is, when the brake liquid pressure at the second piping position A2 is made a specific value or more than the brake liquid pressure at the first piping position A1, the relative pressure relief valve 17 is opened, and lets the brake liquid in the second piping position A2 escape to the first piping position A1, so as to reduce the brak liquid pressure in the second piping position A2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a brake device for a vehicle, and more particularly to a master cylinder pressure generated by a master cylinder or the like when it is desired to obtain a higher braking force on a high μ road or the like. The invention also relates to a brake device capable of exerting a high brake fluid pressure on a wheel cylinder and exhibiting a high braking force.

[0002]

2. Description of the Related Art As a brake device for increasing a brake fluid pressure applied to a wheel cylinder in order to obtain an optimum braking force, for example, there is an automobile brake pressure increasing device disclosed in Japanese Patent Laid-Open No. 7-89432. it can. In this brake device, by increasing the boosting action of the brake pressure booster in a panic braking situation where the occupant hesitates to step on the pedal with the maximum force, the wheel cylinder pressure applied to the wheel cylinder at a normal pedal depression force is increased. It realizes a large wheel cylinder pressure and secures a high braking force.

[0003]

However, as described above, when an abnormality occurs in the means for increasing the wheel cylinder pressure larger than the wheel cylinder pressure when the pedal is normally depressed, the brake fluid pressure becomes excessive. It may increase and adversely affect the braking device.

For example, when a pump is used as a means for increasing the wheel cylinder pressure and the pump driving signal is abnormal and the pump is operated more than necessary, the brake fluid pressure in the pipe line exceeds the pressure resistance. There is a problem that the number of brakes increases and adversely affects the brake piping and the brake system.

In view of this, the present invention amplifies the brake fluid pressure generated by a predetermined brake fluid pressure generation source during braking of the vehicle to secure a high braking force and can prevent an excessive increase in the brake fluid pressure. An object of the present invention is to provide a vehicle brake device.

[0006]

According to a first aspect of the present invention for solving the above-mentioned problems, a predetermined amount of brake fluid is generated by the pressure intensifying means to generate the first brake fluid pressure in the first conduit. It is possible to decrease and increase the brake fluid pressure applied to the braking force generating means to the second brake fluid pressure by using this predetermined amount of brake fluid. That is, since the increase in the first brake hydraulic pressure is suppressed, the load for generating the first brake hydraulic pressure is reduced, and the increased second brake hydraulic pressure is applied to the braking force generating means, It is possible to secure a sufficient braking force (while preventing the reaction force from being generated by the first brake hydraulic pressure).

Particularly, in the present invention, the brake fluid pressure in the second pipeline can be suppressed to the pressure resistance of the second pipeline or less by the restraining means. Therefore, due to excessive brake fluid pressure,
It is possible to prevent adverse effects on various equipment such as brake piping, seals, and brake devices. Further, in the present invention, since the brake fluid pressure does not excessively increase, there is an advantage that the rating for the brake fluid pressure can be kept low.

According to the second aspect of the present invention, a means for inhibiting the execution of the pressure amplifying means can be adopted as the suppressing means. For example, when the pressure amplifying means is a pump, there is a means for prohibiting the output of the drive signal to the pump when the brake fluid pressure in the second conduit reaches a predetermined brake fluid pressure.

In the third aspect of the invention, the suppressing means may be means for releasing the pressure in the second conduit. That is, a means for releasing the brake fluid in the second pipeline to reduce the brake fluid pressure so that the brake fluid pressure in the second pipeline does not exceed the pressure resistance.

In the invention of claim 4, as the suppressing means,
Relative pressure relief valves and / or absolute pressure relief valves may be mentioned. Of these, the relative pressure relief valve opens, for example, when the brake fluid pressure in the second pipeline becomes higher than the brake fluid pressure in the first pipeline by a certain value or more, and the relative pressure relief valve in the second pipeline is opened. By letting the brake fluid escape to the first pipeline, the brake fluid pressure in the second pipeline can be reduced. When a relative pressure relief valve is used, there is little risk of external leakage, so it is highly reliable and suitable for feeling.

The absolute pressure relief valve is opened when a predetermined pressure is reached so that the brake fluid pressure in the second pipeline does not exceed the pressure resistance, and the brake fluid pressure in the second pipeline is opened. Can be reduced. When the absolute pressure relief valve is used, there is an advantage that the brake fluid pressure can be reliably set to a predetermined fluid pressure or less, which is excellent in safety.

According to the invention of claim 5, the pressure amplifying means sucks the brake fluid having the first brake fluid pressure and discharges it to the wheel braking force generating means side, the first brake fluid pressure and the second brake fluid pressure. Holding means for holding a pressure difference between the brake fluid pressure and the brake fluid pressure, and a control valve provided on the suction side of the pump for shutting off and communicating the flow of the brake fluid to the suction side of the pump. Prohibits the control valve from communicating.

That is, when the brake fluid pressure is increased from the first brake fluid pressure to the second brake fluid pressure, the control valve is opened (for example, from the master cylinder) to allow the flow of the brake fluid to the suction side of the pump. The brake fluid is discharged to the wheel braking force generating means side by operating the pump, and the increased brake fluid pressure is held by the holding means. If the brake fluid pressure increased due to pressure increase becomes excessive, the control valve is closed to prohibit the flow of brake fluid to the suction side of the pump, and the brake fluid pressure may increase excessively. Prevent.

As a result, as described in claim 1, it is possible to prevent the adverse effects of excessive brake fluid pressure on the brake pipes, seals and various devices such as the brake device. Further, the rating for the brake fluid pressure can be kept low. In the invention of claim 6, the suppressing means prohibits the control valve from communicating with each other, and
Prohibit pump operation.

This makes it possible to prevent the brake fluid pressure from increasing excessively more effectively.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, preferred embodiments of a vehicle brake device of the present invention will be described in detail with reference to the drawings by taking examples (embodiments). (Embodiment 1) This embodiment is based on the basic configuration of the brake device.
It is a combination of an anti-skid control system, and here, in a front-wheel drive four-wheel vehicle, an X-piping vehicle provided with each piping system of right front wheel-left rear wheel, left front wheel and right rear wheel is according to the invention. An example in which the vehicle brake device is applied will be described.

A) First, the basic structure of the brake device will be described with reference to the brake piping model diagram shown in FIG. In FIG. 1, a brake pedal 1 that is depressed by an occupant when applying a braking force to a vehicle is connected to a booster device 3, and a pedaling force and a pedal stroke applied to the brake pedal 1 are transmitted to the booster device 3. It

The booster 3 has at least two chambers, a first chamber and a second chamber. For example, the first chamber is the atmospheric pressure chamber and the second chamber is the second chamber.
The chamber can be a negative pressure chamber, and the negative pressure in the negative pressure chamber is
For example, an engine intake manifold negative pressure or a vacuum pump negative pressure is used. This booster 3
Then, the pedal depression force or pedal stroke of the occupant is directly boosted by the pressure difference between the atmospheric pressure chamber and the negative pressure chamber, and is transmitted to the master cylinder 5.

The master cylinder 5 is for applying the brake fluid pressure boosted by the booster 3 to the entire brake pipe as will be described later.
The master cylinder 5 is provided with its own master reservoir 7 for supplying brake fluid and storing excess brake fluid in the master cylinder 5.

The master cylinder pressure PU generated in the master cylinder 5 is arranged in the master cylinder 5 and the right front wheel FR and applies a braking force to the first wheel cylinder (W / C) 8 and the master wheel. Cylinder 5 and left rear wheel RL
Is transmitted to the brake fluid in the first piping system A that is connected to the second wheel cylinder 9 that is disposed in the second wheel cylinder 9 and applies a braking force to this wheel. Similarly, the master cylinder pressure PU is also transmitted to a second piping system that connects the master cylinder 5 and each wheel cylinder arranged on the left front wheel and the right rear wheel.
Since a configuration similar to that of the piping system A can be adopted, it will not be described in detail.

The first piping system A is composed of two parts divided by the pressure amplifying means 10 arranged in the first piping system A. That is, the first piping system A includes a first pipe line portion A1 that receives the master cylinder pressure PU between the master cylinder 5 and the pressure amplifying means 10, and the pressure amplifying means 10 to the wheel cylinders 8 and 9. And a second conduit portion A2 in between.

The pressure amplifying means 10 is a power brake for performing so-called brake assist, and when the master cylinder pressure PU is generated in the first piping system A when the brake pedal 1 is depressed, the first piping is generated. The brake fluid in the passage portion A1 is moved to the second pipeline portion A2, and the pressure in the second pipeline portion A2 is maintained at the second brake fluid pressure PL.

In this embodiment, the pressure amplifying means 10 is
It is composed of a proportional control valve (PV) 13 and a pump 15. In the configuration of the first piping system A, the first
Is formed between the proportional control valve 13 and the pump 15 and the master cylinder 5, and the second conduit portion A2 of
Is formed between each wheel cylinder 8, 9 and the proportional control valve 13 and the pump 15.

The pump 15 is connected to the first piping system A in parallel with the proportional control valve 13, and when the master cylinder pressure PU is generated, the pump 15 sucks the brake fluid from the first conduit portion A1 to generate the second hydraulic fluid. Discharge to the conduit portion A2. Proportional control valve 13
In the second brake in which the brake fluid in the first pipeline portion A1 is moved to the second pipeline portion A2 by the pump 15, the brake fluid pressure in the second pipeline portion A2 is larger than the master cylinder pressure PU. When the liquid pressure becomes PL, this differential pressure (PL
-PU) is retained.

The proportional control valve 13 is provided in the first wheel cylinder 8 in order to prevent the rear wheel side from entering the locked state before the front wheel side as much as possible when a load movement or the like occurs during vehicle braking. This is similar to the well-known proportional control valve 13 'that reduces the brake fluid pressure applied to the second wheel cylinder 9, but the connection direction is opposite to the normal direction.

Thus, the pump 15 and the proportional control valve 13
The pressure amplifying means 10 provided with the first master cylinder pressure PU becomes a predetermined master cylinder pressure PU when the brake pedal 1 is depressed.
The brake fluid in the first pipeline portion A1 is moved to the second pipeline portion A2 to reduce the brake fluid pressure (that is, the master cylinder pressure PU) in the first pipeline portion A1 and at the same time to the second pipeline portion A1. The pressure difference is amplified by maintaining the differential pressure between the amplified second brake fluid pressure PL and the master cylinder pressure PU in the portion A2 by the proportional control valve 13. Then, the second brake fluid pressure PL, which is higher than the master cylinder pressure PU, is applied to the wheel cylinders 8 and 9 to ensure a high braking force.

Particularly, in this embodiment, the relative pressure relief valve 17 is arranged in parallel with the pump 15. This relative pressure relief valve 17 is provided when the brake fluid pressure in the pipeline between the proportional control valve 13 and the pump 15 is larger than the brake fluid pressure in the pipeline between the reservoir 20 and the pump 15 by a predetermined value or more. That is, when the brake fluid pressure in the second piping portion A2 becomes larger than the brake fluid pressure in the first piping portion A1 by a predetermined value or more, the valve is opened to release the brake fluid in the second piping portion A to the second portion. The brake fluid pressure in the second piping portion A2 is reduced by letting it escape to the piping portion A1.

As a result, the brake fluid pressure in the second piping portion A2 does not rise above the brake fluid pressure in the first piping portion A1 by a certain level (that is, a predetermined differential pressure or more).・
Next, the function of the proportional control valve 13 will be described. In this embodiment, as shown in FIG. 2A, the proportional control valve 13 is reversely connected. This proportional control valve 13 normally has an action of transmitting the original pressure of the brake fluid to the downstream side with a predetermined damping ratio when the brake fluid flows in the positive direction (arrow Y1 direction). Therefore, when the proportional control valve 13 is reversely connected, when the brake fluid flows in the positive direction with respect to the proportional control valve 13, the second pipeline portion A2 side becomes the above-mentioned source pressure, and the first pipeline portion A1. Side is the downstream side.

Therefore, as shown in FIG. 2 (b), the second brake fluid pressure PL in the second pipeline portion A2 is changed from the straight state to the second brake fluid pressure PL in the second pipeline portion A2 by the pump 15. When the break point pressure P1 set in the proportional control valve 15 becomes equal to or higher than the brake fluid amount as the brake fluid amount increases, the second brake fluid pressure PL in the second pipeline portion A2 is a slope of a straight line. It is transmitted to the first conduit portion A1 according to (that is, a predetermined damping ratio). Therefore, with reference to the master cylinder pressure PU in the first conduit portion A1, the proportional control valve 1
Due to 3, the second brake hydraulic pressure PL increased by the discharge of the pump 15 is held in an amplified state due to the reciprocal of the above-described predetermined damping ratio.

On the other hand, when the brake fluid flows in the opposite direction (the direction of arrow Y2) to the proportional control valve 13, the same brake fluid pressure as the original pressure is exerted on the downstream side without damping the brake fluid pressure. Communicate to. In this case, the source pressure side of the proportional control valve 13 is the first conduit portion A1 side, and the downstream side is the second conduit portion A2 side.

B) Next, the anti-skid control system will be described. The anti-skid control system 30 added to the basic configuration of the brake device described above has the following configuration. First, in the second conduit portion A2,
A first pressure increase control valve 31 for controlling an increase in brake fluid pressure to the first wheel cylinder 8 and a second pressure increase control for controlling an increase in brake fluid pressure to the second wheel cylinder 9. And a valve 32. These first and second pressure increase control valves 31 and 32 are constituted by two-position valves (solenoid valves) capable of controlling the communication / cutoff state. When the two-position valve is controlled to be in the communicating state, the master cylinder pressure PU or the brake fluid pressure due to the discharge of the brake fluid from the pump 15 can be applied to each wheel cylinder 4, 5. During normal braking where anti-skid control is not executed, these first and second pressure increase control valves 3
1, 32 are always controlled to be in communication with each other.

Further, the above-mentioned first and second pressure increase control valves 3
The first pressure reducing control valve 3 is provided in the pipe line connecting the second pipe line portion A2 between the wheel cylinders 1 and 32 and the wheel cylinders 8 and 9 and the second reservoir hole 26 of the reservoir 20 described later.
3 and a second pressure reducing control valve 34 are provided respectively. These first and second pressure reducing control valves 33 and 34 are always closed in the normal braking state.

The communication / cutoff control of the first and second pressure reducing control valves 33 and 34 is performed when the antiskid control is started and the first and second pressure increasing control valves 31 and 32 are turned off. To be executed. That is, the first and second pressure reducing control valves 33,
When 34 is switched off, the current wheel cylinder pressure in the corresponding wheel cylinder is maintained.

When the locked state of the wheels is detected,
The first and second pressure reducing control valves 33 and 34 are brought into communication with each other,
The wheel cylinder pressure of the corresponding wheel cylinder is reduced. At this time, the first and second pressure reducing control valves 33, 3
4, the brake fluid applied to the wheel cylinder passes through the second reservoir hole 26, and is accommodated in the reservoir chamber 27. As a result, each wheel cylinder pressure can be reduced.

When the wheel lock tendency is subsided and it is desired to increase the wheel cylinder pressure, the reservoir chamber 27
The brake fluid stored inside is used to increase the wheel cylinder pressure. That is, the brake fluid is sucked from the second reservoir hole 26 by the pump 15, and the brake fluid pressure is applied to the wheel cylinders 8 and 9 through the first and second pressure increase control valves 31 and 32 which are in the communication state. .

The structure of the reservoir 20 will be described below. A reservoir 20 is connected between the first conduit portion A1 and the pump 15 suction side of the brake fluid. The reservoir 20 has a first reservoir hole 25 that is connected between the master cylinder 5 and the proportional control valve 13 and receives a flow of the brake fluid from a pipe having a pressure equivalent to the master cylinder pressure PU. A ball valve 21 is arranged inside the reservoir 20 from the reservoir hole 25. The ball valve 2 is provided below the ball valve 21.
A rod 23 having a predetermined stroke is provided for moving 1 up and down. In the reservoir chamber 27,
Equipped with a rod 24 and a piston 24 which moves,
The piston 24 slides downward when the brake fluid flows from the second reservoir hole 26, and stores the brake fluid in the reservoir chamber 27. It should be noted that the piston 20 is inserted into the reservoir 20 in a direction to push out the brake fluid in the reservoir chamber 27.
A spring 28 for urging 4 is built in.

When the brake fluid is stored in this way, the piston 24 moves downward. Along with this, the rod 23 also moves downward, and the ball valve 21 contacts the valve seat 22. Therefore, when the brake fluid is stored in the reservoir chamber 27 for more than the stroke of the rod 23,
The ball valve 21 and the valve seat 22 block the flow of the brake fluid between the suction side of the pump 15 and the first conduit portion A1. The ball valve 21, the rod 23 and the valve seat 2
2 has the same effect in the normal brake state before the anti-skid control is executed.

Further, when the brake fluid in the reservoir chamber 27 is consumed by the suction of the pump 15 at the time of increasing the pressure in the anti-study control, the piston 24 moves upward, and the rod 23 causes the ball valve to move accordingly. 21 is moved to the upper side. Therefore, the ball valve 21 separates from the valve seat 22, and the suction side of the pump 15 and the first conduit portion A1 communicate with each other. Then, when communicating in this way, the pump 15 sucks the brake fluid from the first conduit portion A1,
The above-described operation of the pressure amplification means 10 is performed to increase the wheel cylinder pressure.

The anti-skid control described above and the control for moving the brake fluid from the master cylinder 5 side to the wheel cylinders 8 and 9 to increase the braking force are performed by an electronic control unit (ECU) not shown. This ECU
Is configured as a microcomputer including a well-known CPU, ROM, RAM, input / output unit, bus line, and the like.

C) As described above, in this embodiment, the structure in which the anti-skid control system is incorporated in the basic structure of the above-described brake device is adopted, and the relative pressure relief valve 17 is arranged in parallel with the pump 15. . Therefore, the brake fluid pressure in the second piping portion A2 is equal to that in the first piping portion A1.
If the brake fluid pressure exceeds the specified value,
By opening the relative pressure relief valve 17, the brake fluid in the second piping portion A2 can be released to the first piping portion A1, and the brake fluid pressure in the second piping portion A2 can be reduced. .

When the brake fluid pressure in the second piping portion A2 is reduced through the relative pressure relief valve 17, the relative pressure relief valve 17 immediately after the reduction of the brake fluid pressure, the first piping portion A1. , But the piston 24 of the reservoir 20 is pushed downward and the ball valve 21 blocks the first piping portion A1 from the suction port of the pump 15. When,
Since the brake fluid pressure is released by the spring 28 into the reservoir chamber 27 having only a few atmospheres, the relative pressure relief valve 17 has a function close to that of the absolute pressure relief valve.

This state is illustrated in FIG. 3. For example, when the relative pressure relief valve 17 is not provided, the brake fluid pressure (wheel cylinder pressure PL) in the second piping portion A2 is the same as the straight line in FIG. Since the brake fluid pressure rapidly increases, the brake fluid pressure rapidly approaches the pressure resistance of the second piping portion A2 as shown by the alternate long and short dash line. However, in the case where the relative pressure relief valve 17 is provided as in the present embodiment, the relative pressure relief valve 17 is used when the differential pressure ΔP between the wheel cylinder pressure PL and the master cylinder pressure PU exceeds a predetermined value. When opened, the brake fluid is allowed to escape from the high pressure side (second pipeline portion A2) to the low pressure side (second pipeline portion A1), and as shown by the straight line in FIG. 3, the wheel cylinder pressure PL and the master cylinder pressure PU Differential pressure with △ P
Is adjusted so that is below a predetermined value.

As described above, when the brake fluid pressure in the second piping portion A2 is reduced and the ball valve 21 shuts off the first piping portion A1 from the suction port of the pump 15. The relative pressure relief valve 17 functions as an absolute pressure relief valve, as shown by the straight line in FIG.

As a result, the degree of increase in the wheel cylinder pressure PL becomes gentle, so that the wheel cylinder pressure PL is increased.
Becomes difficult to reach the pressure resistance of the pipeline. Accordingly, by using the standard relative pressure relief valve 17 that opens with a differential pressure that does not normally reach, it is possible to substantially prevent the brake fluid pressure in the pipeline from becoming higher than the withstand pressure. for that reason,
This has the effect of increasing the durability of the braking device and reducing its failure.

Further, in this embodiment, since the excessive pressure resistance performance is not required, it is possible to suppress the pressure resistance equipment, and there is an advantage that it contributes to the cost reduction. Furthermore, since the structure that makes it difficult for the brake fluid pressure to reach the pressure resistance of the pipeline is not in the use of a sensor or the like but in the circuit configuration itself, it is not affected by a failure of the sensor or the like and is extremely safe. is there. (Embodiment 2) Next, Embodiment 2 will be described, but the description of the same portions as those in Embodiment 1 will be simplified.

In this embodiment, as in the first embodiment, the basic structure of the brake device is combined with the anti-skid control system. However, not only the relative pressure relief valve but also the absolute pressure relief valve is used. The point is characteristic. First, the basic configuration of the brake device will be described based on the brake piping model diagram shown in FIG.

In FIG. 4, the brake pedal 101 is
The master cylinder 10 is connected to the booster 103.
5 includes a master reservoir 107. The master cylinder pressure PU corresponds to the first and second wheel cylinders 108,
It is transmitted to the brake fluid in the first piping system A reaching 109. Similarly, the master cylinder pressure PU is also transmitted to the second piping system, but since the same configuration as the first piping system A can be adopted, it will not be described in detail.

The first piping system A is pressure amplification means 110.
It consists of two parts divided by. That is,
The first piping system A includes a first pipeline portion A1 that receives the master cylinder pressure PU between the master cylinder 105 and the pressure amplifying means 110, and a portion between the pressure amplifying means 110 and the wheel cylinders 108 and 109. It has the 2nd conduit part A2.

The pressure amplifying means 110 is the brake pedal 1
When 01 is depressed and the master cylinder pressure PU is generated in the first piping system A, the brake fluid in the first piping portion A1 is moved to the second piping portion A2 to The pressure of the pipeline portion A2 is maintained at the second brake fluid pressure PL. In this embodiment, the pressure amplification means 110 is composed of a proportional control valve (PV) 113 and a pump 115.

The pump 115 is connected to the first piping system A in parallel with the proportional control valve 113, and the master cylinder pressure PU
When the above occurs, the brake fluid is sucked from the first pipeline portion A1 and discharged to the second pipeline portion A2. The proportional control valve 113 is reversely connected to the first piping system A, and the pump 115 causes the brake fluid in the first conduit portion A1 to flow in the second direction.
When the brake fluid pressure in the second pipeline portion A2 becomes the second brake fluid pressure PL larger than the master cylinder pressure PU, this differential pressure (PL-PU)
Acts to hold.

The anti-skid control system 130 is provided with the first and second pressure increasing control valves 123 and 125, the first and second pressure reducing control valves 127 and 129, and the reservoir 120. The description is omitted because it is the same as in Example 1. Particularly in this embodiment, the relative pressure relief valve 133 is arranged in parallel with the proportional control valve 113. The relative pressure relief valve 133 includes a proportional control valve 113 and a pump 11.
5 is greater than the brake fluid pressure in the pipe between the proportional control valve 113 and the master cylinder 105 by a predetermined value or more, that is, the second pipe portion A.
When the brake fluid pressure of 2 is greater than the brake fluid pressure of the first piping portion A1 by a predetermined value or more, the valve is opened to allow the brake fluid in the second piping portion A2 to escape to the first piping portion A1. , The brake fluid pressure in the second piping portion A2 is reduced.

As a result, the brake fluid pressure in the second piping portion A2 does not rise above the brake fluid pressure in the first piping portion A1 by a predetermined value or more. An absolute pressure relief valve 135 is provided in addition to the relative pressure relief valve 133. The absolute pressure relief valve 135 is provided in a pipeline connecting the proportional control valve 113 and the pump 115 and the master reservoir 107, and brake fluid in the pipeline between the proportional control valve 113 and the pump 115. When the pressure exceeds the brake fluid pressure in the master reservoir 107 by a predetermined value or more, that is, the brake fluid pressure in the second piping portion A2 is the brake fluid pressure in the master reservoir 107 (approximately atmospheric pressure).
When it becomes larger than a predetermined value, the valve is opened to allow the brake fluid in the second piping portion A to escape to the master reservoir 107 to reduce the brake fluid pressure in the second piping portion A2.

As a result, the brake fluid pressure in the second piping portion A2 does not rise above a predetermined absolute pressure (pressure from atmospheric pressure) beyond a certain level. Thus, in this embodiment,
Since the relative pressure relief valve 133 and the absolute pressure relief valve 135 described above are provided, the safety is higher than that of the first embodiment.

This state is illustrated in FIG. 5. For example, when the relative pressure relief valve 133 is provided but the absolute pressure relief valve 135 is not provided, as shown by the straight line in FIG. The hydraulic pressure (wheel cylinder pressure PL) rapidly increases, then gradually changes at the break point pressure P2, gradually approaches the pressure resistance of the pipeline, and if the state continues as it is, it is indicated by the one-dot chain line. Withstand voltage will be reached. However, in the case where the absolute pressure relief valve 135 is provided as in the present embodiment, even if the wheel cylinder pressure PL increases like a straight line, when the absolute pressure is reached at the break point pressure P3, the absolute pressure relief valve 135. Opens to let the brake fluid escape from the high pressure side to the low pressure side, and as shown by the straight line in FIG. 5, adjust the brake fluid pressure in the pipeline so that it does not exceed the pressure resistance.

As a result, since the wheel cylinder pressure PL does not exceed the pressure resistance, it is possible to prevent the brake device from being adversely affected by the excessive increase of the brake fluid pressure. That is, there is a remarkable advantage that the brake fluid pressure can be surely prevented from being excessively increased as compared with the case where only the relative pressure relief valve 133 is used. (Third Embodiment) Next, a third embodiment will be described, but the description of the same parts as in the first embodiment will be simplified.

In this embodiment, as in the first embodiment, the basic structure of the brake device is combined with an anti-skid control system, but instead of the relative pressure relief valve, the operation of the pump is controlled. It is characterized by adopting. a) First, the configuration of the brake device will be described based on the brake piping model diagram shown in FIG.

In FIG. 6, the brake pedal 201 is
The master cylinder 20 is connected to the booster 203.
5 includes a master reservoir 207. The master cylinder pressure PU is equal to the first and second wheel cylinders 208,
It is transmitted to the brake fluid in the first piping system A reaching 209. Similarly, the master cylinder pressure PU is also transmitted to the second piping system, but since the same configuration as the first piping system A can be adopted, it will not be described in detail.

The first piping system A is pressure amplification means 210.
It consists of two parts divided by. That is,
The first piping system A includes a first pipe line portion A1 that receives the master cylinder pressure PU between the master cylinder 205 and the pressure amplifying means 210, and between the pressure amplifying means 210 and each wheel cylinder 208, 3209. It has the 2nd conduit part A2.

The pressure amplifying means 210 is the brake pedal 2
When 01 is depressed and the master cylinder pressure PU is generated in the first piping system A, the brake fluid in the first piping portion A1 is moved to the second piping portion A2 to The pressure of the pipeline portion A2 is maintained at the second brake fluid pressure PL. In this embodiment, the pressure amplifying means 210 is composed of a proportional control valve (PV) 213 and a pump 215.

The pump 215 is connected to the first piping system A in parallel with the proportional control valve 213, and has a master cylinder pressure PU.
When the above occurs, the brake fluid is sucked from the first pipeline portion A1 and discharged to the second pipeline portion A2. Like the first embodiment, the proportional control valve 213 is reversely connected to the first piping system A, and the pump 215 moves the brake fluid in the first conduit portion A1 to the second conduit portion A2. hand,
When the brake fluid pressure in the second pipeline portion A2 becomes the second brake fluid pressure PL which is larger than the master cylinder pressure PU,
This serves to hold this differential pressure (PL-PU).

The anti-skid control system 220 is provided with the first and second pressure increasing control valves 223 and 225, the first and second pressure reducing control valves 227 and 229, and the reservoir 230. The description is omitted because it is the same as in Example 1. Particularly in the present embodiment, a pressure sensor 231 is provided between the proportional control valve 213 and the master cylinder 205 in order to detect the brake fluid pressure in the first conduit portion A1. And the signal to this pressure sensor 231 is
The control signal is sent to the ECU 235 and a control signal is sent from the ECU 235 to the pump 215.

The ECU 235, as shown in FIG. 7, is a well-known CPU 235a, ROM 235b, RAM 235.
c, an input / output unit 235d, a bus line 235e, and the like. The input / output unit 235d, in addition to the pressure sensor 231, detects a pedal stroke sensor 237 that detects the amount of depression of the brake pedal 201, and detects deceleration acceleration of the vehicle. The G sensor 239, the brake switch 241 for detecting the depression of the brake pedal 201, etc. are connected, and the pump 215, the first and second pressure increasing control valves 223, 225, and the first and second Pressure reducing control valves 227, 22
9 are connected.

The information on the brake fluid pressure obtained by the pressure sensor 231 is for the first pipeline portion A1, but the brake fluid pressure for the first pipeline portion A1 and the information for the second pipeline portion A1. Since there is a predetermined proportional relationship with the brake fluid pressure, the value detected by the pressure sensor 231 is converted into the pressure of the second pipeline portion A2 by a map or the like to brake the second pipeline portion A2. The hydraulic pressure can be calculated. Alternatively, because of the above-described proportional relationship, the brake fluid pressure in the first conduit portion A1 can be used as it is as a value indicating the brake fluid pressure in the second conduit portion A2.

B) Next, the control processing performed by the ECU 235 of this embodiment will be described with reference to the flowchart of FIG. In addition, the ignition is turned on (O
In case of N), it is started. In steps 100 to S130 of FIG. 8 (hereinafter referred to as S), a condition for permitting pressure amplification by the pump 215 (a pressure increasing means execution condition) is calculated.

That is, in S100, the pedal stroke amount Pp is obtained based on the signal from the pedal stroke sensor 237. In subsequent S110, the pedal stroke change amount ΔPP is calculated from the pedal stroke amount PP obtained in S100.

In subsequent S120, the signal from the G sensor 239 is read and the deceleration acceleration ΔVB of the vehicle is calculated.
Then, in subsequent S130, the brake fluid pressure BP in the first pipeline portion A1 is obtained based on the signal from the pressure sensor 231.

In the subsequent S140, the brake pedal 201
Whether or not the pedal is depressed is determined by whether or not the brake switch 241 is on. If an affirmative decision is made here, S
If the determination is negative, the process returns to S100. In S150, the above S100, S110, S120
It is determined whether or not at least one of the values calculated in step 1 is satisfied. That is, each value of the pressure increasing means execution conditions that has already been calculated is compared with a predetermined reference value to determine whether or not even one of the pressure increasing means execution conditions satisfies the reference value. Here, if an affirmative determination is made, the operation proceeds to S160, while if a negative determination is made, the operation returns to S100.

At S160, the detected first conduit portion A
It is determined whether the brake fluid pressure BP of 1 exceeds a predetermined reference value KBP. Note that, here, the brake fluid pressure BP of the first pipeline portion A1 is not converted to the brake fluid pressure of the second pipeline portion A2, but the brake fluid pressure of the second pipeline portion A2 changes to that of the pipeline. The reference value KBP of the brake fluid pressure BP of the first conduit portion A1 is set so that the pressure resistance is not exceeded. Here, if an affirmative decision is made, the operation proceeds to S170, whereas if a negative decision is made, the operation proceeds to S180.

In S170, since the pressure increase is permitted, the pump 215 is driven to increase the brake fluid pressure in the second conduit portion A2. Further, in S180, since the pressure increase is prohibited, the driving of the pump 215 is stopped to prohibit the increase of the brake fluid pressure in the second pipeline portion A2, and S100
Return to

As described above, in this embodiment, even when the brake pedal 201 is depressed, none of the predetermined pressure increasing means execution conditions is satisfied, or (the second conduit portion A2 When the brake fluid pressure BP of the first pipeline portion A1 exceeds the reference value KBP, the driving of the pump 215 is prohibited, so the brake fluid pressure of the second pipeline portion A2 is prohibited. However, it is possible to prevent the pressure from exceeding the pressure resistance of the pipeline due to excessive increase.

In this embodiment, the pressure sensor is arranged in the first conduit portion A1, but the pressure sensor may be arranged in the second conduit portion. In this case, since the brake fluid pressure in the second conduit portion A2 can be directly detected, there is an advantage that appropriate processing can be performed based on the more accurate brake fluid pressure and the calculation processing can be reduced. (Fourth Embodiment) Next, a fourth embodiment will be described.

The present embodiment is greatly different from the first embodiment in that an anti-skid control system is not provided.
The description of the same parts as those in the first embodiment will be simplified or omitted. As shown in FIG. 9, in the present embodiment, the proportional control valve 305 similar to that in the first embodiment is reversely connected to the conduit A extending from the master cylinder 300 to the wheel cylinders 301 and 303.

A pump 307 is arranged in parallel with the proportional control valve 305. This pump 307 pumps the brake fluid from the first pipeline portion A1 to the second pipeline portion A2, so that the brake fluid of the second pipeline portion A2 is greater than the brake fluid pressure of the first pipeline portion A1. It increases the pressure.

Further, a relative pressure relief valve 309 is arranged in parallel with the proportional control valve 305. The relative pressure relief valve 309 is opened when the brake fluid pressure in the second pipeline portion A2 becomes equal to or more than a predetermined value than the brake fluid pressure in the first pipeline portion A1 to release the brake fluid at a high pressure. It escapes from the side (the second conduit portion A1) to the low pressure side (the first conduit portion A1).

Therefore, also in the case of the present embodiment, as in the case of the above-described first embodiment, the brake fluid pressure in the second pipeline portion A2 is the first.
It is possible to prevent the brake fluid pressure in the second pipeline portion A1 from increasing by a predetermined value or more, and thereby to prevent the brake fluid pressure in the second pipeline portion A2 from excessively increasing. (Fifth Embodiment) Next, a fifth embodiment will be described.

The present embodiment is largely different in that an electromagnetic valve is used instead of the proportional control valve of the fourth embodiment and that an absolute pressure relief valve is used instead of a relative pressure relief valve. The description of the same parts as those in the fourth embodiment will be simplified or omitted. As shown in FIG. 10, in this embodiment, the master cylinder 400
In the conduit A from the wheel cylinders 401 and 403, not a proportional control valve, but an electromagnetic valve 405 controlled to open / close two positions is provided.

A pump 407 is arranged in parallel with the solenoid valve 405. The pump 407 pumps the brake fluid from the first pipeline portion A1 to the second pipeline portion A2, so that the brake fluid in the second pipeline portion A2 is greater than the brake fluid pressure in the first pipeline portion A1. It increases the pressure.

Further, the solenoid valve 405 and the wheel cylinder 4
01, 403 between the pipeline (second pipeline portion A2) and the master reservoir 409, the absolute pressure relief valve 41
1 is provided. This absolute pressure relief valve 411
The brake fluid pressure in the second conduit portion A2 is a predetermined value (absolute pressure)
In the above case, the valve is opened to allow the brake fluid to escape from the high pressure side to the low pressure side (master reservoir 409 side; atmospheric pressure).

Therefore, also in the case of the present embodiment, as in the case of using the absolute pressure relief valve of the second embodiment, the brake fluid pressure in the second conduit portion A2 increases more than the pressure resistance of the conduit. This has the advantage that it can be reliably prevented. (Sixth Embodiment) Next, a sixth embodiment will be described, but the description of the same parts as those in the third embodiment will be simplified.

This embodiment is provided with a booster and pressure amplifying means composed of a pump or the like for performing brake assist, and as in the third embodiment, the operation of the pump is controlled according to the brake fluid pressure. Although it controls, a master cylinder cut valve is used instead of the proportional control valve,
It is characterized by using a reservoir cut valve. a) First, the configuration of the brake device will be described based on the brake piping model diagram shown in FIG.

In FIG. 11, the brake pedal 501
Is connected to the booster 503, and the master cylinder 505 includes a master reservoir 507. The master cylinder pressure PU corresponds to the first and second wheel cylinders 50.
It is transmitted to the brake fluid in the first piping system A reaching 8,509. Similarly, the master cylinder pressure PU is also transmitted to the second piping system B, but since a configuration similar to that of the first piping system A can be adopted, it will not be described in detail here.

The first piping system A includes pressure amplification means 510.
It consists of two parts divided by. That is,
The first piping system A includes a first pipe line portion A1 that receives the master cylinder pressure PU between the master cylinder 505 and the pressure amplifying means 510 and between the pressure amplifying means 510 and each wheel cylinder 508, 509. It has the 2nd conduit part A2.

The pressure amplifying means 510 is composed of a master cylinder cut valve (SMC valve) 511, a reservoir cut valve (SRC valve) 513, and a pump 515.
When the master cylinder pressure PU is generated in the pipe system A, the brake fluid in the first pipeline portion A1 is moved to the second pipeline portion A2, and the pressure in the second pipeline portion A2 is increased. The second
The brake fluid pressure PL is maintained at.

The pump 515 is connected to the first piping system A in parallel with the SMC valve 511, and when the master cylinder pressure PU is generated, the brake fluid is sucked from the first conduit portion A1 to generate a first brake fluid. It is discharged to the second conduit portion A2. S
The MC valve 511 is a solenoid valve arranged in a conduit extending from the master cylinder 505 to both wheel cylinders 508 and 509, and is in a communication state when it is off, and a shutoff state when it is on. The SMC valve 511 is provided with a check valve 511a in order to prevent the brake fluid pressure in the second conduit portion A2 from becoming excessively large even in the shutoff state. A check valve 512 is separately provided in parallel with the SMC valve 511 to prevent the master cylinder pressure PU from becoming excessive.

In this SMC valve 511, the pump 515 moves the brake fluid in the first conduit portion A1 to the second conduit portion A2, so that the brake fluid pressure in the second conduit portion A2 becomes the master cylinder pressure. When the second brake fluid pressure PL is greater than PU, the pressure difference (PL-PU) is retained.

The SRC valve 513 is connected to the master cylinder 505.
To a suction side of the pump 515, the solenoid valve is placed in a shutoff state when turned off and in a communication state when turned on. Further, this brake device is provided with well-known first and second pressure increase control valves 523, 525, first and second pressure reduction control valves 527, 529, a reservoir 530, an accumulator 532, etc., and an SMC valve 511.
Between the master cylinder 505 and the master cylinder 505.
In order to detect the brake fluid pressure of 1, the pressure sensor 531
Is provided.

B) Next, an electrical configuration for controlling the brake device will be described. As shown in FIG. 12, the ECU 535 that controls the brake device includes a well-known CPU 535a,
ROM535b, RAM535c, input / output unit 535d,
The bus line 535e is provided.

In addition to the pressure sensor 531, the input / output section 535d of the ECU 535 has a brake pedal 50.
A pedal stroke sensor 537 for detecting the depression amount of 1;
The G sensor 539 for detecting the deceleration acceleration of the vehicle, the brake switch 541 for detecting the depression of the brake pedal 501, etc. are connected, and the SMC valve 5 is connected.
11, SRC valve 513, pump 515 (specifically, pump motor 516 driving pump 515; see FIG. 11),
The first and second pressure increase control valves 523, 525, the first and second pressure reduction control valves 527, 529, etc. are connected.

Although the information on the brake fluid pressure obtained by the pressure sensor 531 is for the first pipeline portion A1, the brake fluid pressure for the first pipeline portion A1 and the information for the second pipeline portion A1 are not included. Since there is a predetermined proportional relationship with the brake fluid pressure, the value detected by the pressure sensor 531 is converted into the pressure of the second pipeline portion A2 by a map or the like, and the brake of the second pipeline portion A2 is calculated. The hydraulic pressure can be calculated. Alternatively, because of the above-described proportional relationship, the brake fluid pressure in the first conduit portion A1 can be used as it is as a value indicating the brake fluid pressure in the second conduit portion A2.

C) Next, the control process performed by the ECU 535 of this embodiment will be described with reference to the flowchart of FIG. It should be noted that this process is started when the ignition is on. In S200 to S230 of FIG. 13, a condition for allowing pressure amplification by the pump 515 (condition for executing pressure increasing means) is calculated.

That is, in S200, the pedal stroke amount Pp is obtained based on the signal from the pedal stroke sensor 537. In subsequent S210, the pedal stroke change amount ΔPP is calculated from the pedal stroke amount PP obtained in S200.

In subsequent S220, the signal from the G sensor 539 is read and the deceleration acceleration ΔVB of the vehicle is calculated.
Then, in subsequent S230, the brake fluid pressure BP in the first pipeline portion A1 is obtained based on the signal from the pressure sensor 531.

In the following S240, the brake pedal 501
Whether or not the pedal is depressed is determined by whether or not the brake switch 541 is on. If an affirmative decision is made here, S
If the determination is negative, the process returns to S200. In S250, the S200, S210, S220
It is determined whether or not at least one of the values calculated in step 1 is satisfied. That is, each value of the pressure increasing means execution conditions that has already been calculated is compared with a predetermined reference value to determine whether or not even one of the pressure increasing means execution conditions satisfies the reference value. Here, if an affirmative determination is made, the operation proceeds to S260, while if a negative determination is made, the operation returns to S200.

At S260, the detected first conduit portion A
It is determined whether the brake fluid pressure BP of 1 exceeds a predetermined reference value KBP. Note that, here, the brake fluid pressure BP of the first pipeline portion A1 is not converted to the brake fluid pressure of the second pipeline portion A2, but the brake fluid pressure of the second pipeline portion A2 changes to that of the pipeline. The reference value KBP of the brake fluid pressure BP of the first conduit portion A1 is set so that the pressure resistance is not exceeded. Here, if an affirmative judgment is made, the routine proceeds to S270, while if a negative judgment is made, the routine proceeds to S280.

In S270, since the pressure increase is permitted, the pressure amplifying means 510 is driven to increase the brake fluid pressure in the second pipe line portion A2. Specifically, SMC valve 5
11 is turned on to be in the cutoff state, and the SRC valve 51
3 is turned on to establish communication, and pump motor 5
16 is turned on to operate the pump 515.

Further, since the pressure increase is prohibited in S280, the increase of the brake fluid pressure in the second conduit portion A2 is prohibited, and the process returns to S200. Specifically, the SMC valve 511
Remains in the on-off state, the SRC valve 513 is turned off to bring it into the shut-off state, and the pump motor 516 is turned off to stop the pump 515.

As described above, in this embodiment, even when the brake pedal 501 is stepped on, none of the predetermined pressure boosting means execution conditions is satisfied, or (the second pipeline portion A2 If the brake fluid pressure BP of the first pipeline portion A1 exceeds the reference value KBP, it is prohibited to increase the brake fluid pressure, so that the brake of the second pipeline portion A2 is performed. It is possible to prevent the hydraulic pressure from excessively increasing and exceeding the pressure resistance of the pipeline.

In this embodiment, the pressure sensor is arranged at the first conduit portion A1, but the pressure sensor may be arranged at the second conduit portion. In this case, since the brake fluid pressure in the second conduit portion A2 can be directly detected, there is an advantage that appropriate processing can be performed based on the more accurate brake fluid pressure and the calculation processing can be reduced.

Further, instead of the process of S280, only the SRC valve 513 may be turned off while the pump 515 is kept operating. This also has the advantage that the brake fluid pressure can be stopped from increasing, and particularly when the pressure increasing is restarted, the response is excellent. The present invention is not limited to the above embodiments, but can be modified in various ways as follows.

(1) For example, in the first embodiment, the pressure amplifying means 10 is composed of the pump 15 and the proportional control valve 13, but the invention is not limited to this, and as shown in FIG.
The first piping system A may have a simple configuration in which the pumps 15 are connected in series. (2) Also, for example, in the first embodiment, the proportional control valve 13
Instead of, the following configurations can be adopted.

As shown in FIG. 15A, the proportional control valve 1
Instead of 3, the solenoid valve 600 controlled to the 2 position, that is,
A solenoid valve 600 having a port 600a having a differential pressure valve and a port 600b realizing a communication state may be used.
A check valve 610 is connected in parallel to the solenoid valve 600.

Further, as shown in FIG. 15B, a throttle 700 may be used instead of the proportional control valve 13. (3) Further, in the first embodiment, the amplification of the brake fluid amount for the second conduit portion A2 by the pressure amplification means 10 is performed for both the right front wheel FR and the left rear wheel RL. However, the amplification of the brake fluid amount by the pressure amplifying means 10 may be performed only on the left and right front wheels. That is, since load movement occurs during vehicle braking, it may not be possible to expect much securing of braking force on the left and right rear wheels. Also,
If a large amount of load movement occurs, a wheel slip may easily occur when a large braking force is applied to the rear wheels. Therefore, in such a case, if the pressure amplification is performed only on the left and right front wheels, the braking force can be efficiently obtained.

(4) Furthermore, in each of the above-mentioned embodiments, the brake fluid pressure is generated by the brake fluid pressure generating means by the master cylinder pressure being generated in the master cylinder by the pedal operation of the occupant. However, the present invention may be applied to, for example, an automatic brake in which the inter-vehicle distance becomes equal to or less than a predetermined distance and the brakes are actuated regardless of how the occupant depresses the brake pedal. At this time, instead of the brake pedal and the master cylinder, a pump for automatic braking or the like may be provided as the brake fluid pressure generating means in the present invention. Even in this case, if the pressure amplifying means according to the present invention is provided, it is possible to reduce the load of generating the first brake hydraulic pressure in the pump or the like that constitutes the brake hydraulic pressure generating means.

(5) Further, if the second brake fluid pressure can be increased by the pressure amplifying means as in the present invention,
It is possible to reduce the capacity of the booster configured in the above-mentioned embodiment to reduce the size, or it is possible to discontinue. That is, even if the booster does not increase the master cylinder pressure, the burden on the pedal effort of the occupant can be sufficiently reduced and a high braking force can be secured.

(6) Further, in the embodiment shown in FIG. 4 in which the inside of the reservoir in the anti-skid control is used as the flow path of the brake fluid in the pressure amplifying means, for example, the area of the piston in the reservoir and the rod (extending from the piston) By appropriately setting the flow passage area around the, the set pressure of the spring, the suction capacity of the pump, etc., and the ball valve is closed when the pressure generated in the master cylinder becomes a predetermined value or more, The effect in the above embodiment can be achieved by only mechanical components.

(7) In the above embodiment, the present invention is applied to the front-wheel-drive X-piping vehicle, but the present invention can be carried out without being limited to the driving system and the piping system. It is also applicable to a vehicle or the like having front and rear pipes of front wheel-left front wheel and right rear wheel-left rear wheel.

[Brief description of drawings]

FIG. 1 is a brake piping model diagram showing a first embodiment.

2A and 2B show a proportional control valve of Example 1, where FIG. 2A is an explanatory diagram thereof and FIG.

FIG. 3 is a graph showing a change in brake fluid pressure according to the first embodiment.

FIG. 4 is a brake piping model diagram showing a second embodiment.

FIG. 5 is a graph showing changes in brake fluid pressure according to the second embodiment.

FIG. 6 is a brake piping model diagram showing a third embodiment.

FIG. 7 is a block diagram showing an electrical configuration of a third embodiment.

FIG. 8 is a flowchart illustrating a control process according to a third embodiment.

FIG. 9 is a brake piping model diagram showing a fourth embodiment.

FIG. 10 is a brake piping model diagram showing a fifth embodiment.

FIG. 11 is a brake piping model diagram showing a sixth embodiment.

FIG. 12 is a block diagram showing an electrical configuration of a sixth embodiment.

FIG. 13 is a flowchart showing a control process of the sixth embodiment.

FIG. 14 is an explanatory diagram showing another example of the pressure amplification means.

FIG. 15 is an explanatory diagram showing another example in which the proportional control valve is replaced.

[Explanation of symbols]

1, 101, 201, 501 ... Brake pedal 3, 103, 203, 503 ... Booster device 5, 105, 205, 300, 400, 505 ... Master cylinder 8, 108, 208, 301, 401, 508 ... First Wheel cylinder 9,109,209,303,403,509 ... Second wheel cylinder 10,110,210,510 ... Pressure amplification means 13,113,213,305 ... Proportional control valve 15,115,215,307,407 , 515 ... Pump 17, 133, 309 ... Relative pressure relief valve 135, 411 ... Absolute pressure relief valve A ... First piping system A1 ... First pipeline part A2 ... Second pipeline part 20, 130, 230 , 530 ... Reservoir 231, 531 ... Pressure sensor 235, 535 ... ECU 405, 600 ... Solenoid valve 511 ... Master Ttobarubu (SMC valve) 513 ... reservoir cut valve (SRC valve) 700 ... stop

Claims (6)

[Claims] 1. A brake fluid pressure generation unit having a generation source that generates a first brake fluid pressure to apply a braking force to a vehicle, a braking force generation unit that generates a braking force on wheels, and the brake fluid pressure generation. A first conduit for communicating the means with the braking force generating means, wherein the first brake fluid pressure is generated in the first conduit when the first brake fluid pressure is generated. The brake fluid amount for generating the brake fluid pressure is reduced by a predetermined amount, and the brake fluid pressure applied to the braking force generating means is changed to a second amount by using the brake fluid amount for the predetermined amount of reduction.
Pressure amplifying means for increasing the brake fluid pressure to the braking force generating means and transmitting the braking fluid pressure to the braking force generating means;
A brake device for a vehicle, comprising: a suppressing unit configured to suppress the brake fluid pressure in the pipeline to a pressure resistance of the second pipeline or less. 2. The suppressing means is means for prohibiting the execution of the pressure amplifying means.
The vehicle brake device according to any one of the preceding claims. 3. The control means according to claim 1, wherein the suppressing means is means for releasing the pressure in the second pipeline.
The vehicle brake device according to any one of the preceding claims. 4. The vehicle brake system according to claim 3, wherein the suppressing means is a relative pressure relief valve and / or an absolute pressure relief valve. 5. The pump for amplifying the pressure, wherein the pressure amplifying means sucks the brake fluid having the first brake fluid pressure and discharges the brake fluid to the wheel braking force generating means side, the first brake fluid pressure and the second brake fluid pressure. A holding means for holding a pressure difference between the pump and a brake fluid pressure; and a control valve provided on the suction side of the pump for blocking and communicating the flow of the brake fluid to the suction side of the pump, The vehicle brake device according to claim 1, wherein the suppressing unit prohibits the control valve from communicating with each other. 6. The vehicle brake device according to claim 5, wherein the suppressing means prohibits the control valve from communicating with each other and prohibits the operation of the pump.