JPH1120661A - Hydraulic brake device for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To restrain fluctuation of fluid pressure supplied for boosting to secure excellent braking operation feeling in a hydraulic brake device for a vehicle provided with a hydraulic booster means. SOLUTION: In this device, a control piston 30 exposing its rear side to a pressure chamber R4 and forming a regulator chamber R6 in its front side is liquid-tightly and freely slidably stored in the front of a master piston 20 inside a cylinder body 1, being arranged to interlocking to the master piston 20. Provided are a boost pressure poppet valve mechanism 60 interlocking to the control piston 30 to communicate or block a sub-hydraulic source 40 to a power chamber R1, a pressure reducing spool valve mechanism 50 interlocking to the control piston to communicate or block the power chamber to a reservoir 4, and a unidirectional valve means (a check valve 80) allowing only a flow of brake fluid supplied from the boost pressure poppet valve mechanism 60 to the power chamber.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic brake device for supplying brake hydraulic pressure to a wheel cylinder of a vehicle wheel, and more particularly to a vehicle hydraulic brake device provided with a hydraulic booster.

[0002]

2. Description of the Related Art Various types of hydraulic brake devices for automobiles are known, and a device provided with a hydraulic booster is disclosed in U.S. Pat. No. 3,928,970. . The publication discloses a master cylinder using the pressure of a pressurized fluid source, having a piston slidably housed in a cylinder bore, and forming a pressure chamber connected to a brake hydraulic circuit in front of the piston. A master cylinder device is disclosed in which a power chamber connected to a source of pressurized fluid is formed at the rear and a valve device for controlling supply of fluid from the source of pressurized fluid is disclosed. It is an object of the publication to provide a master cylinder having a source of pressurized fluid in which a piston is directly driven by a brake pedal operation, but does not require an inlet or an inlet seal that moves in a pressurized state. A first pressure chamber is formed between the first piston and the second piston and connected to a hydraulic circuit, and a second pressure chamber is formed in front of the second piston to form a first piston. , And an introduction valve for introducing the output hydraulic pressure of the pressurized fluid source into the second pressure chamber, and a discharge valve connecting the second pressure chamber to the reservoir. There has been proposed a master cylinder device configured to be driven in accordance with the operation of a piston.

In GB 2170874A, a servo chamber is formed on the back of the first piston, and a servo chamber is provided to the servo chamber from a source of pressurized fluid. Servo pressurization master cylinder devices configured to supply pressurized fluid via a valve have been proposed. In the device described in this publication, a spool valve is arranged vertically or parallel to a master cylinder.

[0004]

In the apparatus described in the above publication, the pressurized fluid after pressure adjustment through a valve device is supplied to a power chamber (servo chamber). I have. As for the pressure adjusting operation as a so-called regulator, the balance between the regulator hydraulic pressure and the master cylinder hydraulic pressure applied to the front and rear of the control piston is adjusted by a valve device. In such a device, the output hydraulic pressure of the regulator is used not only for boost drive but also for various brake hydraulic pressure controls such as anti-skid control.

However, in the above master cylinder device, the regulator hydraulic pressure fluctuates when subjected to brake hydraulic pressure control, so that the hydraulic pressure in the power chamber also fluctuates according to the fluctuation of the regulator hydraulic pressure. Further, the pressure pulsation also causes the pedal effort of the brake pedal to fluctuate, which may impair the brake operation feeling of the vehicle driver.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a vehicle hydraulic brake device having a hydraulic booster, which suppresses fluctuations in hydraulic pressure for boosting and ensures a good brake operation feeling. .

[0007]

In order to achieve the above object, a vehicle hydraulic brake device according to the present invention comprises a reservoir for storing brake fluid, and a master piston slidably and slidably in a cylinder body. A pressure chamber is formed in front of the master piston and a power chamber is formed behind the master piston. Brake fluid in the reservoir is introduced into the pressure chamber, and a brake is applied from the pressure chamber in accordance with sliding of the master piston. At least one master cylinder that outputs hydraulic pressure, an auxiliary hydraulic pressure source that boosts the brake fluid in the reservoir to a predetermined pressure and outputs power hydraulic pressure, and a front of the master piston in the cylinder body. A control piston, which is slidably housed in a liquid-tight manner and is arranged so as to interlock with the master piston, and a control piston having a rear portion exposed to the pressure chamber; and the auxiliary hydraulic pressure interlocked with the control piston. Valve means for communicating or shutting off the power chamber with the power chamber, pressure reducing valve means for communicating or shutting off the power chamber with the reservoir in conjunction with the control piston, and a brake supplied from the pressure increasing valve means to the power chamber. One-way valve means permitting only the flow of liquid, and one end of the one-way valve means is connected to the pressure-intensifying valve means side, and the brake fluid pressure output from the pressure-increasing valve means is changed according to the driving state of the vehicle. And a hydraulic pressure control means provided to a wheel cylinder of each wheel.

In the above-mentioned hydraulic brake device for a vehicle, the one-way valve means is provided in an opening to the power chamber in a hydraulic passage connecting the pressure-intensifying valve means to the power chamber. It can be composed of a valve.

Further, in the hydraulic brake system for a vehicle, the master cylinder, the control piston, the pressure reducing valve means and the pressure increasing valve means are disposed coaxially in the cylinder body, and are provided in front of the control piston. A regulator chamber may be formed between the pressure reducing valve means and the power chamber communicating with the reservoir via the regulator chamber when the pressure reducing valve means communicates.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a hydraulic brake device according to an embodiment of the present invention. A master cylinder MC and a regulator RG are formed in a cylinder body 1. The master cylinder MC of this embodiment has two pressure chambers R.
A so-called diagonal pipe is constituted by a tandem master cylinder on which R2 and R4 are formed. That is, when a pedaling force is applied to a brake pedal 2 which is a brake operating member provided on the rear side of the vehicle (the right side in FIG. 1), the pedaling force is transmitted as a brake operating force via a push rod 3 and the master is accordingly actuated. Two pressure chambers R2, R of cylinder MC
The output brake fluid pressure from the wheel cylinders Wfr and Wr of the front right and rear left wheels FR and RL, respectively, of the vehicle
l, and output to the wheel cylinders Wfl, Wrr of the front left and rear right wheels FL, RR. At this time, a regulator hydraulic pressure is output from the regulator RG in accordance with the operation of the brake pedal 2, and the master cylinder MC is assisted in accordance with the operation of the regulator RG as described later.

The cylinder body 1 has holes 1 having different inner diameters.
a, 1b, 1c and the like are formed with stepped holes, in which master pistons 10, 20 and control piston 30 are formed.
Is housed, and a pressure chamber R is provided between the master pistons 10 and 20.
2, the master piston 20 and the control piston 30
And a pressure chamber R4 is formed. The rear end of the hole 1a communicates with a power chamber R1 having a larger inner diameter. The smallest hole 1b and the larger hole 1
Both ends of the control piston 30 are slidably fitted in both liquid-tight manners.

As shown in the enlarged view of FIG. 2, the master piston 10 has a land portion 11 formed on an outer surface of a front end portion thereof, and an annular seal member 12 and an annular seal member 13 having a cup-shaped cross section. The master piston 20 is mounted so as to be slidably fitted to the hole 1 a in a liquid-tight manner, with the front end face facing the rear end face of the master piston 20. Therefore, the sealing member 1
The power chamber R1 and the pressure chamber R2 are separated by 2 and 13. The main body 14 of the master piston 10 is supported by a cylindrical sleeve 15. This sleeve 15
An annular groove is formed on the inner surface and the outer surface, and an annular groove is also formed on the inner surface separated from the inner surface by a predetermined distance in the axial direction. Each of these grooves has an annular sealing member 16,
17 and an annular seal member 18 having a cup-shaped cross section are accommodated, and the sealing performance with respect to the power chamber R1 is ensured. Further, a concave portion 10a is formed in the axial direction from the distal end surface of the master piston 10, and a retainer 1 is formed at the distal end portion.
9 is mounted.

A land portion 21 is formed at the rear end of the outer periphery of the master piston 20, and a land portion 22 having the same diameter as the land portion 21 is formed on the front side at a predetermined distance in the axial direction. The land portions 21 and 22 are provided with annular sealing members 23 and 24 each having a cup-shaped cross section, and are slidably fitted in the hole 1a in a liquid-tight manner. Also,
Recesses 20a, 2 in the axial direction from both ends of master piston 20
0b is formed, and a hole 20c is formed in the radial direction of the master piston 20, and the bottom thereof communicates with the recess 20a through the communication hole 20d. The annular liquid supply chamber R3 formed between the lands 21 and 22 communicates with the reservoir 4 via the port 1e, and the liquid supply chamber R3 is connected to the pressure chamber R2 via the hole 20c, the communication hole 20d and the recess 20a. Can communicate with Further, a retainer 2 is provided at the tip of the master piston 20.
9 is mounted.

A retainer 25 is mounted on the rear end side of the master piston 20, and a valve body 26 is locked to the retainer 25 so that the valve body 26
In the direction of the master piston 10 is restricted.
An elastic member such as rubber is attached to the tip of the valve body 26, and is configured to abut on the communication hole 20d to seal it. A rod 27 is integrally formed on the other end side of the valve body 26, and a locking portion 28 is formed at a rear end of the rod 27. The locking portion 28 is movably arranged in the recess 10a, and the retainer 1
9, the movement in the direction of the master piston 20 is restricted. And, the retainer 1 of the master piston 10
The spring 5 is stretched between the retainer 9 and the retainer 25 of the master piston 20, and is urged in a direction separating the two. The retracted position of the master piston 20 is regulated by a locking pin 7 fixed to the cylinder body 1.

As shown in FIG. 3 on an enlarged scale, a large-diameter land 31 is formed at the rear end of the outer periphery of the control piston 30 and a small-diameter land is formed at a predetermined distance in the axial direction on the front side. A land portion 32 is formed, and an annular seal member 33 having a cup-shaped cross section is disposed on the land portion 31 so as to be slidably fitted in the hole 1a in a liquid-tight manner, and the land portion 32 slides in the hole 1b. They are freely fitted. Thus, the pressure chamber R4 and the liquid supply chamber R5 are separated by the seal member 33, and the liquid supply chamber R5 and a regulator chamber R6 described later are separated by the seal member.
Are separated. That is, the liquid supply chamber R5 is formed between the seal member 33 and the seal member 34, and the liquid supply chamber R5 is connected to the reservoir 4 through the port 1t.

The control piston 30 has a recess 30a and a stepped recess 30b at both ends in the axial direction, and a communication hole 30c penetrating in the radial direction. The communication hole 30c communicates with the bottom of the recess 30a via the communication hole 30d. A retainer 35 is mounted on the rear end side of the control piston 30, and a valve body 36 having the same configuration as the above-described valve body 26 is locked to the retainer 35, thereby restricting the movement of the valve body 36 in the direction of the master piston 10. . A rod 37 is formed integrally with the other end of the valve body 36, and a locking portion 38 is formed at the rear end. The locking portion 38 is movably disposed in the recess 20b, and engages with the retainer 29. Control piston 30 stopped
Movement in the direction is regulated. On the other hand, control piston 3
In the bottom of the stepped concave portion 30b, a spool 53 described later is provided.
The rear end is held. Also, the master piston 20
The spring 6 is stretched between the retainer 29 of the control piston 30 and the retainer 35 of the control piston 30, and is urged in a direction separating the two.

As shown in FIG. 1, a regulator RG is formed in front of the cylinder body 1, and an auxiliary hydraulic pressure source 40 is connected to the regulator RG, and its output power hydraulic pressure is appropriately controlled, for example, as shown in FIG. The regulator hydraulic pressure is output to the hydraulic pressure control device PC indicated by a two-dot chain line in FIG. The hydraulic pressure control device PC includes, for example, a solenoid valve, a controller, and the like for performing anti-skid control and the like, and is configured such that the regulator hydraulic pressure supplied to the wheel cylinder Wfr and the like is appropriately controlled according to the driving state of the vehicle. Have been. The auxiliary hydraulic pressure source 40 includes a hydraulic pump 42 driven by an electric motor 41. The input side is connected to the reservoir 4 and the output side is connected to the accumulator 43. The regulator RG is connected to the accumulator 43 via the port 1p.
Is configured to be supplied with power hydraulic pressure.

As shown in FIG. 3, the regulator RG has a stepped cylindrical body sleeve 51 fitted in a stepped hole 1c communicating with the hole 1b. A plurality of annular grooves are formed on the outer periphery of the sleeve 51, and an annular seal member is fitted to each. In addition, communication holes 51e and 51f are formed between the adjacent seal members in the radial direction of the sleeve 51, and the hollow portions of the sleeve 51 are connected to the port 1s and the hydraulic path P1 via these holes. . A regulator chamber R6 is formed between the rear end surface of the sleeve 51 and the front end surface of the control piston 30, and is connected to the power chamber R1 (FIGS. 1 and 2) via a hydraulic pressure path P2. Holes 51a, 51b, 51 are formed in the hollow portion of the sleeve 51.
The inside of the hole 51b having the smallest diameter is a drain chamber R7 that communicates with the reservoir 4 via the communication hole 51e and the port 1s.

A sleeve 52 is further housed in the hole 51a, and a stepped hole 52a is formed in a hollow portion thereof, and a communication hole 52b communicating with the regulator chamber R6 is formed in a radial direction orthogonal to the hole. Have been. A spool 53 is slidably received in the stepped hole 52 a of the sleeve 52. A plunger 54 is accommodated in the hole 51b. A base 54a of the plunger 54 is slidably supported by the hole 51b. A rear end face of the plunger 54 is disposed so that a distal end face of the spool 53 of the spool valve mechanism 50 abuts. I have.

A cylindrical elastic member 70 made of rubber, for example, is fitted into the hole 51c. The plunger 54 extends through the hole 51c and the tip of the plunger 54 extends into the poppet valve mechanism 60. . An annular transmission member 71 is interposed between the base portion 54a of the plunger 54 and the elastic member 70, and an annular concave portion is formed on the surface of the elastic member 70 opposite to the surface in contact with the transmission member 71. . Further, a plate 72 is disposed on the front end surface of the elastic member 70, and is configured so that the hydraulic pressure is uniformly applied to the entire surface of the elastic member 70. A power output chamber R8 is formed between the elastic member 70 in the hole 51c and the poppet valve mechanism 60, and communicates with the hydraulic pressure path P1 via the communication hole 51f of the sleeve 51. This hydraulic path P1 is connected to the power chamber R as shown in FIG.
1 and the power chamber R1 is connected to the regulator chamber R6 via a hydraulic path P2. In other words, the power output chamber R8, the hydraulic pressure path P1, the power chamber R1, the hydraulic pressure path P2, and the regulator chamber R6 constitute a pressure regulation chamber.

As shown in FIGS. 1 and 2, a check valve 80, which is a one-way valve of the present invention, is provided at a connection portion of the hydraulic passage P1 to the power chamber R1. This check valve 80
A valve seat 82 is formed at the bottom of a bottomed cylindrical case 81, a ball valve 83 is housed in the case 81, and a spring 84
Thus, the ball valve 83 is configured to be urged in a direction of sitting on the valve seat 82. The one-way valve is not limited to the check valve 80, and another valve device may be used.
The hydraulic pressure control device PC is connected to the hydraulic pressure passage P1 between the power output chamber R8 and the check valve 80 as shown by a two-dot chain line in FIG. On the other hand, a pressure sensor (not shown) used for brake fluid pressure control by the fluid pressure control device PC is disposed downstream of the check valve 80.

The spool valve mechanism 50 constitutes the pressure reducing valve means of the present invention, and has a stepped cylindrical spool 53 as shown in an enlarged view in FIG. 4, and a plurality of labyrinth grooves are formed in a large diameter portion thereof. ing. A retainer 54 is supported at an intermediate portion of the spool 53, and the retainer 54 is supported within the stepped recess 30 b of the control piston 30. And
A spring 55 is provided between the retainer 54 and the sleeve 52.
And the spool 53 is urged to abut the bottom surface of the stepped recess 30b of the control piston 30.

In the fitting portion of the spool 53 to the sleeve 52, the communication hole 52b is always open to the regulator chamber R6, and communicates with the drain chamber R7 at the initial position of the spool 53. The flow path area is limited by the large diameter portion, and the communication hole 52b is finally shielded. As shown in FIG. 3, the drain chamber R7 is provided with the communication hole 51e of the sleeve 51 and the port 1
s is connected to the reservoir 4 (FIG. 1). Therefore, at the initial position of the spool 53, the inside of the regulator chamber R6 also communicates with the reservoir 4, and is filled with the brake fluid at atmospheric pressure. Note that the pressure reducing valve means is not limited to the spool valve mechanism 50, and may be another mode, and may be arranged not in the regulator RG but in the vicinity of, for example, the power chamber R1.

The poppet valve mechanism 60 constitutes the pressure increasing valve means of the present invention, and is constructed as shown in FIG.
The sleeve 61 is a cylindrical body having a bottom and has a hollow portion 61a formed in the axial direction and a radial communication hole 61 communicating with the hollow portion 61a.
b is formed, and a sleeve 61 is formed in parallel with the hollow portion 61a.
The communication hole 61c which penetrates is formed. A communication hole 61d is formed in the center of the bottom of the sleeve 61 in the axial direction, and a valve seat 61e is formed on the hollow portion 61a side. A plurality of annular grooves are formed on the outer periphery of the sleeve 61, and annular seal members are respectively fitted therein, and a communication hole 61b is formed between adjacent seal members, and a hollow is formed through the communication hole 61b. The portion 61a is connected to the port 1p shown in FIGS.

In the hollow portion 61a of the sleeve 61, a valve member 63, a retainer 64, a spring 65 and a filter 66 are provided.
Is accommodated, and a stepped cylindrical sleeve 62 is provided in the hollow portion 61a.
When the small diameter portion is fitted, the hollow portion 61a of the sleeve 61
A power input chamber R9 is formed therein. The power input chamber R9 can communicate with the power output chamber R8 (FIG. 3) through the communication hole 61d. A hole 62a is formed in the sleeve 62 in the axial direction.
Are formed, and a communication hole 62b is formed in a radial direction orthogonal to the hole 62a. The valve member 63 has a valve body 63a formed at the tip, and a large-diameter portion 63 through a flange portion 63b.
c, a stepped cylindrical body including a middle diameter portion 63d and a small diameter portion 63e is formed, and the middle diameter portion 63d is slidably supported by the hole 62a of the sleeve 62. The opening area of the hole 62a is set to be substantially equal to the seat area of the valve body 63a on the valve seat 61e.

The valve member 63 is housed in the hollow portion 61a of the sleeve 61 together with the filter 66. When the spring 65 is stretched between the flange 63b of the valve member 63 and the retainer 64, the valve body 63a is moved to the valve seat. It is urged in the direction of sitting on 61e. In this state, the middle diameter portion 63d of the valve member 63
The small-diameter portion of the sleeve 62 is fitted into the hollow portion 61a of the sleeve 61 so as to be supported by a. At this time, a gap 62c is formed between the front end face of the sleeve 61 and the rear end face of the sleeve 62, and the hole 62a is formed in the communication hole 62b and the gap 6b.
Through the communication hole 2c and the communication hole 61c of the sleeve 61, it communicates with the power output chamber R8, that is, the top surface side of the valve body 63a of the valve member 63 seated on the valve seat 61e. As a result, substantially equal pressure is applied to the valve member 63 from both ends in the axial direction, so that the load on the valve member 63 is extremely small. Although the plunger 54 is disposed so as to face the valve body 63a of the valve member 63, a slight clearance is formed between the valve body 63a and the tip of the plunger 54 at the initial position shown in FIG.

In the initial position shown in FIGS. 1 and 3, the inside of the regulator chamber R6 is provided with the communication hole 52 of the sleeve 52.
a, 52b, the communication hole 51e of the sleeve 51, and the port 1s, which communicate with the reservoir 4 and are at atmospheric pressure. When the control piston 30 moves forward, the spool 53 moves forward. Sleeve 5 as shown
The second communication hole 52b is blocked by the outer peripheral surface of the spool 53, and the valve member 63 of the poppet valve mechanism 60 opens instead, as shown in FIG. Thereby, the power hydraulic pressure of the auxiliary hydraulic pressure source 40 is first supplied to the power chamber R1 via the hydraulic pressure path P1 and the check valve 80, and further supplied to the regulator chamber R6 via the hydraulic pressure path P2. The pressure in the room is increased. When the force of the regulator hydraulic pressure applied to the front land portion 32 of the control piston 30 exceeds the force of the master cylinder hydraulic pressure applied to the rear land portion 31, the control piston 30 moves rearward and the valve member of the poppet valve mechanism 60. Since the valve 63 is closed and the spool 53 of the spool valve mechanism 50 is opened, the pressure in the regulator chamber R6 (and the power chamber R1, the power output chamber R8, and the hydraulic paths P1, P2) is reduced.
By repeating such operations, the pressure in the same chamber is adjusted to a predetermined regulator hydraulic pressure.

Next, the overall operation of the hydraulic brake device having the above configuration will be described. FIGS. 1 to 3 show a state in which the brake pedal 2 is not operated. From this state, the brake pedal 2 is operated, and the master piston 10 is moved forward (to the left in FIG. 1) via the push rod 3. When pressed, the valve body 26 comes into contact with the master piston 20 and the valve body 26
The communication hole 20d is closed by the elastic member of the pressure chamber R.
The communication between the liquid supply chamber R3 and the liquid supply chamber R3 is interrupted, and a closed state is established. Further, the valve body 36 comes into contact with the control piston 30, and the communication hole 30d is closed by the elastic member of the valve body 36, so that the pressure chamber R4
The communication between the liquid supply chamber R5 and the liquid supply chamber R5 is interrupted, and a closed state is established. Thus, the communication between the pressure chamber R2 and the liquid supply chamber R3 and the pressure chamber R
When the master piston 10 is driven by the operating force of the brake pedal 2 in a state where the communication between the master piston 10 and the liquid supply chamber R5 is interrupted, the master pistons 10 and 20 are connected via the spring 5 to the master piston 20 and the control piston. Since 30 is held in the state shown in FIGS. 2 and 3 via the spring 6, respectively, they advance together.

Accordingly, the communication hole 52b is closed by the spool 53 supported by the control piston 30, and the communication with the reservoir 4 is cut off. At the same time, the power hydraulic pressure of the auxiliary hydraulic pressure source 40 is supplied to the power chamber R1 via the check valve 80 and the hydraulic pressure path P1. As a result, the master pistons 10 and 20 advance, and the pressure chambers R2 and R4 are further compressed.
Master cylinder hydraulic pressure is output from ports 1x and 1y. At this time, since the seal diameter of the land portion 31 of the control piston 30 is larger than the seal diameter of the land portion 32, the control is performed such that a regulator hydraulic pressure that is higher than the master cylinder hydraulic pressure is generated as the control piston 30 moves. Thus,
In response to the operation of the brake pedal 2, the movement of the master piston 10 is assisted by the power hydraulic pressure (that is, the regulator hydraulic pressure) supplied from the power output chamber R8 to the power chamber R1 via the hydraulic pressure path P1. .

During this time, the force applied to the control piston 30 by the regulator hydraulic pressure in the regulator chamber R6 is:
If the force applied to the control piston 30 by the master cylinder hydraulic pressure in the pressure chambers R2 and R4 is larger than the force applied to the control piston 30, the spool 53 of the spool valve mechanism 50 opens and the poppet valve mechanism 60
The control piston 30 moves in the direction in which the valve member 63 of (3) closes, and the pressure in the regulator chamber R6 is reduced. When the relationship of the force applied to the control piston 30 is reversed, the control piston 30 moves in the direction in which the spool 53 of the spool valve mechanism 50 closes and the valve member 63 of the poppet valve mechanism 60 opens.
Moves, and the pressure inside the regulator chamber R6 is increased. The regulator hydraulic pressure is adjusted to a pressure higher than the master cylinder hydraulic pressure by a predetermined value or more by repeating the movement of the control piston 30 and the accompanying opening and closing operations of the spool valve mechanism 50 and the poppet valve mechanism 60.

Specifically, the force by the regulator hydraulic pressure applied to the pressure receiving area of the small diameter land portion 32 of the control piston 30 and the force by the master cylinder hydraulic pressure applied to the pressure receiving area of the large diameter land portion 31 Is controlled to be equal to or higher than the master cylinder hydraulic pressure by a predetermined value or more, and a regulator hydraulic pressure that is substantially proportional to the master cylinder hydraulic pressure is output. Brake fluid pressure characteristics are obtained. Further, when the elastic member 70 is deformed by the power hydraulic pressure in the power output chamber R8, the elastic member 70 comes into contact with the transmission member 71, and the valve member 63 is pressed in a direction in which the valve member 63 is seated on the valve seat 61e. Is pressed in the direction in which the opening area to the communication hole 52b increases. As a result, the regulator hydraulic pressure is reduced, and a second brake hydraulic pressure characteristic having a pressure increasing gradient that is gentler than the pressure increasing gradient of the first brake hydraulic pressure characteristic between the brake pedal input and the master cylinder hydraulic pressure is obtained. Can be

According to the hydraulic brake system of the present embodiment, the regulator hydraulic pressure is supplied to the wheel cylinders Wfr and the like under the control of the hydraulic pressure control device PC according to the operating condition of the vehicle. Brake fluid pressure control is performed. For example, when performing anti-skid control or the like, a solenoid valve (not shown) in the hydraulic pressure control device PC is controlled to open and close according to the braking state of the vehicle, so that the wheel cylinders are prevented from locking the wheels FR and the like. The regulator hydraulic pressure supplied to Wfr and the like is controlled. At this time, the check valve 80 allows the flow of the brake fluid from the poppet valve mechanism 60 to the power chamber R1, and prevents the flow in the reverse direction. Therefore, even when the brake fluid is consumed under the control of the fluid pressure control device PC and the pressure is instantaneously reduced, the check valve 8
With 0, the pressure in the power chamber R1 can be maintained. Thereby, the pressure fluctuation in the power chamber R1 can be suppressed, and the pulsation to the brake pedal 2 can be suppressed, and a good brake operation feeling can be secured.

In general, a pressure sensor (not shown) is arranged to monitor the operation state of the brake pedal 2, but in this embodiment, the check valve 80 is connected to the hydraulic passage P1.
Since the pressure fluctuation in the power chamber R1 is suppressed, if the pressure sensor is disposed downstream of the check valve 80, noise in the output of the pressure sensor will also be reduced. Less, and therefore better control accuracy is obtained.

[0034]

Since the present invention is configured as described above, the following effects can be obtained. That is, in the vehicle hydraulic brake device according to the first aspect, the control piston whose rear portion is exposed to the pressure chamber is slidably housed in front of the master piston in the cylinder body in a liquid-tight manner, and is interlocked with the master piston. Pressure increasing valve means for communicating or shutting off the auxiliary hydraulic pressure source to or from the power chamber in conjunction with the control piston; pressure reducing valve means for communicating or shutting off the power chamber with the reservoir in conjunction with the control piston; One-way valve means for allowing only the flow of the brake fluid supplied from the pressure valve means to the power chamber is provided, and one end of the one-way valve means is connected to the pressure increasing valve means side, and the brake fluid pressure output from the pressure increasing valve means is provided. Is provided to the wheel cylinders of the respective wheels in accordance with the driving state of the vehicle, so that the brake fluid is consumed when the hydraulic pressure control means is operated and the pressure is instantaneously reduced. Even if it is possible to maintain the pressure of the power chamber by a one-way valve means. Thus, pressure fluctuations in the power chamber can be suppressed, and pulsation to the brake operation member can be suppressed, and a good brake operation feeling can be secured. In particular, when performing various brake fluid pressure controls by the fluid pressure control means, if a pressure sensor is disposed to monitor the state of the brake operating member, the pressure fluctuation in the power chamber is suppressed by the one-way valve means. Therefore, noise in the output of the pressure sensor is small, and thus good control accuracy can be obtained.

According to a second aspect of the present invention, the one-way valve means is provided in a hydraulic passage connecting the pressure-intensifying valve means to a power chamber.
If the check valve is provided at the opening to the power chamber, the check valve can be easily assembled with a simple structure, so that an inexpensive device can be obtained.

In the hydraulic brake device according to the third aspect, the master cylinder, the control piston, the pressure reducing valve means and the pressure increasing valve means are disposed coaxially in the cylinder body, and the front of the control piston and the pressure reducing valve means are provided. Since the regulator chamber is formed between the pressure chamber and the pressure chamber, the power chamber communicates with the reservoir through the regulator chamber when the pressure reducing valve means communicates, so that the hydraulic brake device is reduced in size.

[Brief description of the drawings]

FIG. 1 is a sectional view of a vehicle hydraulic brake device according to an embodiment of the present invention.

FIG. 2 is an enlarged sectional view showing a master cylinder portion in the vehicle hydraulic brake device according to one embodiment of the present invention.

FIG. 3 is an enlarged sectional view showing a regulator portion in the vehicle hydraulic brake device according to one embodiment of the present invention.

FIG. 4 is an enlarged sectional view showing a spool valve mechanism in the vehicle hydraulic brake device according to one embodiment of the present invention.

FIG. 5 is an enlarged sectional view showing a poppet valve mechanism in the vehicle hydraulic brake device according to one embodiment of the present invention.

FIG. 6 is an enlarged sectional view showing an operation state of a spool valve mechanism according to the embodiment of the present invention.

FIG. 7 is an enlarged sectional view showing an operating state of the poppet valve mechanism according to the embodiment of the present invention.

[Explanation of symbols]

Reference Signs List 1 cylinder body, 2 brake pedal, 4 reservoir 10, 20 master piston, 30 control piston 40 auxiliary hydraulic pressure source 50 spool valve mechanism, 60 poppet valve mechanism 70 elastic member, 80 check valve MC master cylinder, RG regulator R1 power chamber , R2, R4 Pressure chamber R3, R5 Liquid supply chamber R6 Regulator chamber, R7 Drain chamber R8 Power input chamber, R9 Power output chamber P1, P2 Hydraulic pressure passage

Claims (3)

[Claims] A reservoir for storing brake fluid, a master piston slidably housed in a cylinder body in a fluid-tight manner, a pressure chamber formed in front of the master piston, and a power chamber formed rearward of the master piston. At least one master cylinder for introducing brake fluid in the reservoir into the pressure chamber and outputting brake fluid pressure from the pressure chamber in response to sliding of the master piston, and applying a predetermined pressure to the brake fluid in the reservoir; An auxiliary hydraulic pressure source that outputs power hydraulic pressure by increasing the pressure in the cylinder body, and is disposed in the cylinder body so as to be slidably accommodated in front of the master piston in a liquid-tight manner and interlocked with the master piston. A control piston exposed to the pressure chamber, pressure-intensifying valve means for communicating or shutting off the auxiliary hydraulic pressure source to or from the power chamber in conjunction with the control piston; Pressure-reducing valve means for communicating or shutting off the power chamber with the reservoir, one-way valve means for permitting only the flow of brake fluid supplied from the pressure-increasing valve means to the power chamber, and the pressure increasing means for the one-way valve means. One end connected to the pressure valve means side, and a hydraulic pressure control means for applying brake fluid pressure output from the pressure intensifying valve means to the wheel cylinders of each wheel according to the driving state of the vehicle. Hydraulic brake device for vehicles. 2. The method according to claim 1, wherein the one-way valve means is a check valve provided at an opening to the power chamber in a hydraulic passage connecting the pressure increasing valve means to the power chamber. Item 4. The vehicle hydraulic brake device according to Item 1. 3. The system according to claim 1, wherein said master cylinder, said control piston, said pressure reducing valve means and said pressure increasing valve means are coaxially disposed within said cylinder body, and a regulator is provided between the front of said control piston and said pressure reducing valve means. 2. The hydraulic brake device for a vehicle according to claim 1, wherein a chamber is formed, and the power chamber communicates with the reservoir via the regulator chamber when the pressure reducing valve means communicates.