JPH07149220A - Brake hydraulic pressure control device of vehicle - Google Patents

Abstract

PURPOSE:To sufficiently improve brake hydraulic pressure control precision at the time of traction control by furnishing a cut valve interposed between a first electromagnetic opening and closing valve and an output hydraulic pressure chamber. CONSTITUTION:At the time of normal braking by way of stepping on a brake pedal 3, output hydraulic pressure of a master cylinder M works on a wheel brake BFL for a left front wheel through a constantly opened type electromagnetic valve 6FL a cut valve 28, an output hydraulic pressure chamber 34 of a hydraulic pressure transmission means 27 and a hydraulic pressure passage 8FL. In a brake hydraulic pressure control device, since hydraulic pressure in correspondence with quantity of energizing electricity of a linear solenoid 53 is outputted from an output port 50 of a linear solenoid valve 26 and exerted on the wheel brake BFL for the front left wheel through the hydraulic pressure transmission means 27 by controlling the quantity of the energizing electricity of the linear solenoid 53 at the time of carrying out traction control, it is possible to improve hydraulic pressure control precision at the time of the traction control.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a master cylinder provided with a first reservoir and a first electromagnetic opening / closing valve provided between wheel brakes mounted on driving wheels, and a second reservoir and the wheel brakes. And a hydraulic pump having a suction port connected to the second reservoir and a discharge port connected to the master cylinder, and antilock control and traction control are possible. A brake fluid pressure control device for a vehicle.

[0002]

2. Description of the Related Art Conventionally, such an apparatus has been used, for example, as an actual flat opening 5.
It is already known from Japanese Patent Publication No. 56712.

[0003]

The above-mentioned prior art is provided with a pump exclusively for traction control, and in traction control, the hydraulic pressure applied to the wheel brakes of the drive wheels is controlled by the operation control of the traction control pump. It is difficult to say that the brake fluid pressure control accuracy during traction control is sufficient.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a vehicle brake fluid pressure control device capable of sufficiently improving the accuracy of brake fluid pressure control during traction control. To do.

[0005]

To achieve the above object, the present invention provides a master cylinder having a first reservoir and a first electromagnetic on-off valve interposed between wheel brakes mounted on driving wheels. , A second electromagnetic on-off valve interposed between the second reservoir and the wheel brake, and a hydraulic pump having a suction port connected to the second reservoir and a discharge port connected to the master cylinder. In a brake fluid pressure control device for a vehicle, a third electromagnetic opening / closing valve provided between a fluid pressure pump and a master cylinder, and first and second solenoid valves.
A fourth electromagnetic on-off valve provided between the reservoirs, an accumulator connected between the hydraulic pump and the third electromagnetic on-off valve via a check valve, and the hydraulic pressure of the accumulator to the energizing quantity of the linear solenoid. A linear solenoid valve that can be adjusted and output accordingly, and a free piston that has both ends facing the input hydraulic chamber that communicates with the output port of the linear solenoid valve and the output hydraulic chamber that communicates with the wheel brakes can slide on the cylinder body. The fitted hydraulic pressure transmission mechanism and the free piston to the side that reduces the volume of the output hydraulic chamber while maintaining the valve open state when the free piston is at the position where the volume of the input hydraulic chamber is minimized. When the piston moves, the valve can be closed except when the hydraulic pressure from the first electromagnetic opening / closing valve is greater than the hydraulic pressure in the output hydraulic chamber by a predetermined value or more. Characterized in that it comprises a cut valve which is interposed between the power hydraulic pressure chamber.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a brake fluid pressure control device for a front-wheel drive vehicle will be described below with reference to the drawings.

First, referring to FIG. 1, a tandem master cylinder M includes a first reservoir R ₁ and a brake pedal 3.
It is equipped with a pair of output ports 1 and 2 that output a braking fluid pressure according to the depression of the vehicle. The left front wheel, which is a driving wheel, has a left front wheel brake B _FL , and the right front wheel, which is a driving wheel, has a right wheel. A front wheel wheel brake B _FR , a left rear wheel which is a driven wheel, a left rear wheel wheel brake B _RL , and a right rear wheel which is a driven wheel are mounted a right rear wheel wheel brake B _RR .

[0008] hydraulic passage 4 ₁ connected to one output port 1 of the master cylinder M is normally open electromagnetic valves 6 _FL is first solenoid valve is connected to the normally open electromagnetic valve 6 _FL is Check valve 7 _FL is connected in parallel. Further, traction control hydraulic pressure switching means 9 _FL is provided between the hydraulic pressure passage 8 _FL connected to the left front wheel brake B _FL and the normally open solenoid valve 6 _FL, and the hydraulic pressure passage 8 _FL is It is connected to the second reservoir R ₂₁ via a normally closed solenoid valve 10 _FL and a check valve 11 _FL which are second solenoid opening / closing valves.

The hydraulic passage 4 ₁ is a normally open solenoid valve 6 _RR.
And a hydraulic circuit 8 _RR connected to the right rear wheel wheel brake B _RR via a parallel circuit including the check valve 7 _RR ,
The hydraulic passage 8 _RR is connected to the second reservoir R ₂₁ via a normally closed solenoid valve 10 _RR and a check valve 11 _RR .

The suction port of the hydraulic pump 13 ₁ is connected to the second reservoir R ₂₁ via the suction valve 12 _1, and the discharge port of the hydraulic pump 13 ₁ is the discharge valve 14 ₁ The solenoid valve is connected to the fluid pressure passage 4 ₁ via a normally open solenoid valve 15 ₁ which is a 3 solenoid on-off valve, a damper chamber 16 ₁ and an orifice 17 ₁ .

[0011] hydraulic passage 4 ₂ connected to one output port 2 in the master cylinder M is normally open electromagnetic valve 6 _FR is the first solenoid valve is connected to the normally open electromagnetic valve 6 _FR is Check valve 7 _FR is connected in parallel. Further, a traction control hydraulic pressure switching means 9 _FR is provided between the hydraulic pressure passage 8 _FR connected to the front right wheel wheel brake B _FR and the normally open solenoid valve 6 _FR, and the hydraulic pressure passage 8 _FR is It is connected to the second reservoir R ₂₂ via a normally closed solenoid valve 10 _FR and a check valve 11 _FR which are second solenoid opening / closing valves.

The hydraulic passage 4 ₂ is a normally open solenoid valve 6 _RL.
And a hydraulic circuit 8 _RL connected to the left rear wheel wheel brake B _RL via a parallel circuit including the check valve 7 _RL ,
The hydraulic passage 8 _RL is connected to the second reservoir R ₂₂ via a normally closed solenoid valve 10 _RL and a check valve 11 _RL .

The suction port of the hydraulic pump 13 ₂ is connected to the second reservoir R ₂₂ via the suction valve 12 _2, and the discharge port of the hydraulic pump 13 ₂ is the discharge valve 14 ₂ It is connected to the hydraulic pressure passage 4 ₂ via a normally open solenoid valve 15 ₂ which is a 3 solenoid on-off valve, a damper chamber 16 ₂ and an orifice 17 ₂ .

Both hydraulic pumps 13 ₁ and 13 ₂ are driven by a common motor 18. In addition, the second reservoirs R ₂₁ , R
₂₂ is commonly connected to the release passage 20 via the one-way valves 19 ₁ and 19 ₂ , and a fourth electromagnetic opening / closing is provided between the release passage 21 communicating with the first reservoir R ₁ and the release passage 20. A normally closed solenoid valve 22 which is a valve is provided.

Discharge valve 14 ₁ and normally open solenoid valve 15
₁ and the discharge valve 14 ₂ and the normally open solenoid valve 15 ₂
The check valves 23 _FL and 23 _FR are connected in common to the accumulator 24.
A pressure sensor 25 for detecting the hydraulic pressure of the accumulator 24 and controlling the accumulated pressure value is connected to the.

In such a brake fluid pressure control device, during normal braking in which each wheel is not likely to be locked, the normally open solenoid valves 6 _{FL to} 6 _RL are demagnetized and opened. The normally closed solenoid valves 10 _FL to 10 _RL are closed in a demagnetized state, and the traction control hydraulic pressure switching means 9 _FL and 9 _FR are normally open solenoid valves 6 _FL and 6 _FR. And the fluid pressure lines 8 _FL and 8 _FR are in communication with each other. Therefore, the braking fluid pressure output from one output port 1 of the master cylinder M acts on the left front wheel brake B _FL via the _normally open solenoid valve 6 _FL, and at the same time via the normally open solenoid valve 6 _RR. The braking fluid pressure acting on the right rear wheel wheel brake B _RR and output from the other output port 2 of the master cylinder M is _supplied to the right front wheel wheel brake B via the _normally open solenoid valve 6 _FL.
It acts on _FR and also acts on the left rear wheel wheel brake B _RL via the _normally open solenoid valve 6 _RL .

At the time of anti-lock control when the wheel is about to enter the locked state during braking, the normally open solenoid valve corresponding to the wheel that is about to enter the locked state among the normally open solenoid valves 6 _{FL to} 6 _RL. The normally closed solenoid valves corresponding to the above wheels among the normally closed solenoid valves 10 _FL to 10 _RL are excited and opened. Then, a part of the braking fluid pressure is released to the second reservoirs R ₂₁ and R ₂₂ and reduced in pressure. When the braking fluid pressure is maintained, the normally open solenoid valves 6 _{FL to} 6 _RL are excited and closed, and the normally closed solenoid valves 10 _FL to 10 _RL are demagnetized and held in the closed state. Well, when increasing the brake fluid pressure, normally open solenoid valves 6 _{FL to} 6
_RL is demagnetized to open the valve and the normally closed solenoid valve 10 _FL ~ 1
It suffices to demagnetize 0 _RL and keep it closed. Further, during traction control, the traction control hydraulic pressure switching means 9 _FL , 9 _FR shuts off between the normally open solenoid valves 6 _FL , 6 _FR and the hydraulic pressure passages 8 _FL , 8 _FR, and the linear solenoid valve 2
The hydraulic pressure from 6 is indirectly applied to the hydraulic pressure passages 8 _FL and 8 _FR , and by controlling the output hydraulic pressure of the linear solenoid valve 26, the wheel brakes B _FL and B _FR for the left front wheel and the right front wheel are obtained. The hydraulic pressure adjusted to can be applied.

By the way, the hydraulic circuit corresponding to the left front wheel wheel brake B _FL and the hydraulic circuit corresponding to the right front wheel wheel brake B _FR have basically the same configuration. Only the hydraulic circuit corresponding to the front wheel brake B _FL will be described.

In FIG. 2, the traction control hydraulic pressure switching means 9 _FL includes a hydraulic pressure transmission mechanism 27 for indirectly acting the output hydraulic pressure of the linear solenoid valve 26 on the wheel brake B _FL for the left front wheel, and a hydraulic pressure passage. 8 _FL and the normally open solenoid valve 6 _FL are provided with a cut valve 28 that can be shut off.

The hydraulic pressure transmission mechanism 27 is provided between the cylinder body 31 whose both ends are closed, and the input hydraulic chamber 33 formed between one end wall 31a of the cylinder body 31 and the other end wall 31b of the cylinder body 31. The free piston 32 slidably fitted into the cylinder body 31 with both ends facing the output hydraulic chamber 34 formed in the above, and the free piston 32 is urged to the side where the volume of the input hydraulic chamber 33 is reduced. And a return spring 35 that exerts a spring force to be housed in the output hydraulic chamber 34. The input hole 3 communicating with the input hydraulic chamber 33 is provided at one end of the cylinder body 31.
6 is provided, an output hole 37 communicating with the output hydraulic chamber 34 is provided at the other end side of the cylinder body 31, and a hydraulic pressure passage 38 communicating with the output port 50 of the linear solenoid valve 26 is connected to the input hole 36. The hydraulic passage 8 _FL connected to the front left wheel brake B _FL is connected to the output hole 37.

The cut valve 28 is connected to the _normally open solenoid valve 6 _FL and is provided with a valve hole 39 provided at the center of the other end wall 31b of the cylinder body 31, and the output hydraulic pressure by making the valve hole 39 openable and closable. A valve body 40 housed in the chamber 34 and a valve spring 41 for urging the valve body 40 in the valve closing direction are provided.

In the output hydraulic chamber 34, a dish-shaped retainer 42 that abuts the inner surface of the other end wall 31b of the cylinder body 31 and a dish-shaped retainer 43 that abuts the free piston 32 are housed and returned. The spring 35 is contracted between the retainers 42 and 43.

The valve element 40 is fixedly housed in the retainer 42 by being fixedly mounted on the front end portion (upper end portion in FIG. 2) of the valve shaft 44 that movably penetrates the center portion of the retainer 42. A regulating flange portion 44a is provided near the front end to regulate the movement of the valve shaft 44, that is, the valve body 40, in a direction away from the valve hole 39 by engaging with the inner surface of the retainer 42. Thus, the valve spring 41 is set to have a smaller spring load than the return spring 35, and the inner surface of the retainer 42 and the valve shaft 44 are set.
It is contracted between the front end of and.

The free piston 32 is provided with a bottomed accommodating recess 45 coaxial with the valve shaft 44 and opening toward the output hydraulic pressure chamber 34 side, and a valve penetrating the center of the retainer 43 movably. The rear end of the shaft 44 is movably inserted into the storage recess 45. At the rear end of the valve shaft 44, the retainer 4
By being engaged with 3, there is provided a restricting flange portion 44b for restricting the movement of the valve shaft 44, that is, the valve body 40 toward the valve hole 39.

According to such a traction control hydraulic pressure switching means 9 _FL , the hydraulic pressure from the linear solenoid valve 26 does not act on the input hydraulic chamber 33, and the free piston 32 of the hydraulic pressure transmitting means 27 inputs it. In the state where the hydraulic chamber 33 is in a position where the volume of the hydraulic chamber 33 is minimized (the state shown in FIG. 2), the regulating collar portion 44b
The valve shaft 40 engaged with the retainer 43 moves the valve body 40 to a position where the valve hole 39 is opened against the spring force of the valve spring 41, and the cut valve 28 is opened. Further, in response to the hydraulic pressure acting on the input hydraulic chamber 33, the hydraulic pressure transmitting means 27
When the free piston 32 is moved to the side that reduces the volume of the output hydraulic chamber 34, the retainer 43 is released from the engagement of the restricting flange portion 44b, so that the valve shaft 44 is driven by the spring force of the valve spring 41. The valve body 40 can be moved to a position where the valve hole 39 is closed, and the cut valve 28 can be closed by the spring force of the valve spring 41. However, in this state, from the normally open solenoid valve 6 _FL side to the output hydraulic chamber 3
When a hydraulic pressure higher than the hydraulic pressure of 4 by a predetermined value or more acts on the valve hole 39, the valve body 40 can move to the position where the valve hole 39 is opened against the spring force of the valve spring 41, and the cut is performed. The valve 28 can be opened.

The linear solenoid valve 26 includes an input port 48 connected to the accumulator 24 and a first reservoir R.
Release port 49 leading to ₁ and hydraulic pressure transmission means 27
Housing 51 having an output port 50 communicating with the input hydraulic chamber 33 via the hydraulic passage 38, a spool 52 slidably fitted in the housing 51, and a housing for axially pressing the spool 52. And a linear solenoid 53 attached to 51.

The drive rod 54 of the linear solenoid 53 is coaxially brought into contact with the rear end of the spool 52, and the housing 5
An output chamber 55 that faces the front end surface of the spool 52 is formed in the inside 1. Moreover, the output chamber 55 communicates with the output port 50, and the return spring 56 that biases the spool 52 toward the linear solenoid 53 is housed in the output chamber 55. Therefore, the spool 52 always comes into contact with the drive rod 54 by the spring force of the return spring 56.

The housing 51 is provided with a cylinder hole 57 into which the spool 52 is slidably fitted. Further, an annular recess 58 that is in constant communication with the output chamber 55 is provided on the outer surface of the spool 52, and the spool 52 has an annular recess 58.
To the release port 49 to release the hydraulic pressure of the output chamber 55, and the forward position to communicate the annular recess 58 with the input port 48 to communicate the output chamber 55 with the input port 48. The switching is performed in accordance with the axial position change due to the magnitude relationship between the thrust of the linear solenoid 53 acting on the end and the hydraulic pressure of the output chamber 55 acting on the axial front end. Further, at the front end of the spool 52, the housing 51
A regulation flange 60 is provided which abuts a step portion 59 provided on the inner surface of the spool and regulates the backward limit of the spool 52.

By the way, the linear solenoid 53 generates a thrust force according to the amount of urging electricity, and the hydraulic pressure of the output chamber 55, that is, the hydraulic pressure output from the output port 50, is urged by the linear solenoid 53. It can be arbitrarily adjusted by controlling the amount of electricity.

[0030] now be described with respect to the left front wheel brake B _FL for the operation of this embodiment, when accumulates the hydraulic pressure accumulator 24, the normally open electromagnetic valves 6 _FL and as shown in Figure 2 The normally closed solenoid valve 10 _FL is kept demagnetized, but the normally open solenoid valve 15 ₁ is excited and closed, and the normally closed solenoid valve 22 is excited and opened. Operate the hydraulic pump 13 ₁ .
Then, the first reservoir R provided in the master cylinder M
Hydraulic fluid from ₁ is supplied to the accumulator 24 by a hydraulic pump 13 _1, predetermined hydraulic pressure is accumulated in the accumulator 24 by the hydraulic pump 13 ₁ to a predetermined hydraulic pressure by the pressure sensor 25 is driven It will be. At this time, since the linear solenoid 53 of the linear solenoid valve 26 is deenergized and the hydraulic pressure is not output from the output port 50, the free piston 32 of the hydraulic pressure transmitting means 27 minimizes the volume of the input hydraulic chamber 33. The cut valve 28 is in the open state.

In this state, during normal braking with the brake pedal 3 depressed, the output hydraulic pressure of the master cylinder M is the normally open solenoid valve 6 _FL , the cut valve 28, and the output hydraulic pressure chamber of the hydraulic pressure transmitting means 27. It acts on the wheel brake B _FL for the left front wheel via the hydraulic pressure passage 34 and the hydraulic pressure passage 8 _FL .

At the time of the above braking, the wheel brake for the left front wheel
B_FLLeft front wheel as soon as you are about to lock
Brake B_FLWhen reducing the braking fluid pressure of
Normally open solenoid valve 6_FLExcited to close the valve, normally closed
Solenoid valve 10_FLThe normally open solenoid valve 15₁To
Demagnetized and opened, normally closed solenoid valve 22 was demagnetized and closed
In this state, the motor 18 drives the hydraulic pump 13₁To activate
Meru. Then, wheel brake B for the left front wheel_FLOf hydraulic fluid
Part of the second reservoir R_{twenty one}And the braking fluid pressure is reduced.
To be done. The second reservoir R_{twenty one}The hydraulic fluid that was released to
Hydraulic pump 13 ₁To normally open solenoid valve 15₁, Damper room 1
6₁And orifice 17₁Through the normally open solenoid valve 6_FLof
It is returned to the upstream side. Therefore, the second reservoir R_{twenty one}Escape to
Brake pedal in master cylinder M
The depression amount of 3 does not increase, and the brake pedal 3
By causing some kickback to
That the vehicle driver is in progress.
You can Moreover, the hydraulic pump 13₁Actuation sent from
Liquid pulsation is in the damper chamber 16₁And orifice 17₁Work of
Pulsation is transmitted to the brake pedal 3
There is no such thing. The pressure sensor 25 detects a predetermined pressure
Motor 18, that is, hydraulic pump 13₁But
It cannot be activated.

In order to maintain the braking fluid pressure of the wheel brake B _FL for the left front wheel during such antilock control, the normally closed solenoid valve 10 _FL may be demagnetized and closed as shown in FIG. When the braking fluid pressure of the front wheel brake B _FL for the left front wheel is further increased, as shown in FIG. 5, the normally open solenoid valve 6 _FL is demagnetized to open and the normally closed solenoid valve 10 _FL is demagnetized. And close the valve. Then, the hydraulic pressure from the master cylinder M acts on the left front wheel brake B _FL , and the braking hydraulic pressure is increased. At this time, the pedal stroke of the brake pedal 3 is abnormally increased by the initial set pressure (for example, gas pressure) of the accumulator 24 even if the accumulator 24 is not sufficiently accumulated with hydraulic pressure due to a failure of the pressure sensor 25 or the like. There is no.

When the traction control is executed when the left drive wheel is likely to slip excessively during vehicle acceleration in the non-brake operation state, the normally open solenoid valve 15 ₁ is excited as shown in FIG. Then, the normally closed solenoid valve 22 is excited to open the valve, so that the accumulator 24, the hydraulic pump 13 ₁ and the master cylinder M are shut off from each other, and the first and second reservoirs R ₁ are closed. ，
Put R ₂₁ in communication. When the linear solenoid 53 of the linear solenoid valve 26 is electrically energized in this state, the output port 50 of the linear solenoid valve 26 outputs a hydraulic pressure corresponding to the energizing amount of the linear solenoid 53. The hydraulic pressure from the output port 50 acts on the input hydraulic chamber 33 of the hydraulic pressure transmission means 27. As a result, the free piston 32 operates in a direction to decrease the volume of the output hydraulic chamber 34, the cut valve 28 is closed accordingly, and the hydraulic pressure increased by the decrease in the volume of the output hydraulic chamber 34 is applied to the left front wheel. It will act on the wheel brake B _FL .

Even when the traction control is executed, the hydraulic pump 13 ₁ is operated in response to the hydraulic pressure detected by the pressure sensor 25, and a constant hydraulic pressure is constantly accumulated in the accumulator 24.

In such a brake fluid pressure control device, when the traction control is executed, the linear solenoid 5
By controlling the energizing amount of the linear solenoid 53, the hydraulic pressure corresponding to the energizing amount of the linear solenoid 53 is output from the output port 50 of the linear solenoid valve 26, and the hydraulic pressure transmitting means 2
Since it acts on the wheel brake B _FL for the front left wheel via 7, it is possible to improve the hydraulic pressure control accuracy during traction control.

Further, when the brake operation is performed during execution of the traction control, the normally open solenoid valve 6 which is in the valve open state.
_When the hydraulic pressure from _FL exceeds a predetermined value, the cut valve 28 is opened, and the hydraulic pressure from the master cylinder M can be applied to the left front wheel brake _BFL .

By the way, in this embodiment, a single linear solenoid valve 26 is provided corresponding to the wheel brakes B _FL , B _FR for the left front wheel and the right front wheel, and traction control for both the left and right front wheels is performed. It is executed at the same time.

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

For example, when the left and right rear wheels are driving wheels, the linear solenoid valve 26,
The hydraulic pressure transmission mechanism 27 and the cut valve 28 may be provided, and the linear solenoid valve 26 is provided corresponding to the wheel brakes for the left and right drive wheels to control the traction of the left and right drive wheels. It is also possible to execute them individually.

[0041]

As described above, according to the present invention, during the traction control, the free piston is driven and cut by the output hydraulic pressure of the linear solenoid valve that outputs the hydraulic pressure according to the energizing amount of the linear solenoid. By closing the valve and indirectly applying the output hydraulic pressure of the linear solenoid valve, the hydraulic pressure of high precision is applied to the wheel brakes, and it is possible to improve the brake hydraulic pressure control accuracy during traction control. When the brake operation is performed during the execution of the control, the cut valve can be opened to apply the braking hydraulic pressure associated with the brake operation to the wheel brakes.

[Brief description of drawings]

FIG. 1 is an overall hydraulic circuit diagram of a brake hydraulic pressure control device for a vehicle.

FIG. 2 is a hydraulic circuit diagram related to the left front wheel brake when accumulator pressure is accumulated.

FIG. 3 is a hydraulic circuit diagram corresponding to FIG. 2 during depressurization during antilock control.

FIG. 4 is a diagram of FIG. 2 when a hydraulic pressure is maintained during antilock control.
It is a hydraulic circuit diagram corresponding to.

FIG. 5 is a diagram when the hydraulic pressure is increased during anti-lock control.
It is a hydraulic circuit diagram corresponding to.

FIG. 6 is a hydraulic circuit diagram corresponding to FIG. 2 during traction control.

[Explanation of symbols]

6 _FL , 6 _FR ... Normally open solenoid valve as first solenoid on-off valve 10 _FL , 10 _FR ... Normally closed solenoid valve as second solenoid on / off valve 13 ₁ , 13 ₂ ... Hydraulic pressure Pumps 15 ₁ , 15 ₂ ... Normally open solenoid valve as third solenoid on-off valve 22 ... Normally closed solenoid valve as fourth solenoid on-off valve 23 _FL , 23 _FR ... Check valve 24 ... -Accumulator 26 ... Linear solenoid valve 27 ... Hydraulic pressure transmission mechanism 28 ... Cut valve 31 ... Cylinder body 32 ... Free piston 33 ... Input hydraulic chamber 34 ... Output hydraulic pressure chamber 50 ... output port 53 ... linear solenoid B _FL, B _FR ... wheel brakes M ... master cylinder R ₁ ... first reservoir R _21, R ₂₂ ... second reservoir

Claims (1)

[Claims] 1. A first solenoid opening / closing valve (6 _FL ) provided between a master cylinder (M) having a _first reservoir (R ₁ ) and wheel brakes (B _FL , B _FR ) mounted on driving wheels. , 6 _FR ) and the second reservoir (R ₂₁ , R ₂₂ ) and the second brake provided between the wheel brakes (B _FL , B _FR ).
Electromagnetic on-off valves (10 _FL , 10 _FR ) and second reservoir (R
₂₁ and R ₂₂ ) having a suction port connected thereto and a discharge port connected to the master cylinder (M) (1)
3 _1, 13 ₂₎ and the brake fluid pressure control apparatus for a vehicle comprising a hydraulic pump (13 _1, 13 ₂₎ and the master cylinder (M) third electromagnetic on-off valve which is provided between (1
5 ₁ , 15 ₂ ) and the first and second reservoirs (R ₁ ; R
_21, R ₂₂₎ fourth solenoid valve which is interposed between the (22),
Check valve (23 _FL , 23 _FR ) between the hydraulic pump (13 ₁ , 13 ₂ ) and the third solenoid on-off valve (15 ₁ , 15 ₂ ).
And a hydraulic pressure of the accumulator (24) connected to the linear solenoid (53).
Of the linear solenoid valve (26) capable of adjusting and outputting according to the amount of urging electricity of the wheel, the input hydraulic chamber (33) communicating with the output port (50) of the linear solenoid valve (26), and the wheel brake (B _FL , B _FR ) leading to the output hydraulic chamber (3
4) a hydraulic pressure transmission mechanism (27) in which a free piston (32) facing both ends is slidably fitted to a cylinder body (31), and the free piston (32) is an input hydraulic chamber (33). When the free piston (32) is moved to the side where the volume of the output hydraulic chamber (34) is decreased, the first solenoid valve (6 _{FL) is held.} , 6 _FR ) output hydraulic pressure chamber (34)
A cut provided between the first electromagnetic opening / closing valve (6 _FL , 6 _FR ) and the output hydraulic chamber (34) that can be closed except when the hydraulic pressure is larger than a predetermined value by a predetermined value or more. Valve (2
8) A brake fluid pressure control device for a vehicle, comprising: