JPH08258690A - Brake device of vehicle - Google Patents

Abstract

PURPOSE: To make compensation of leakage at the second solenoid valve connected between wheel brakes and the first solenoid valve, enhance the feeling in the brake operation, and establish a brake control at the time of non-braking operation simply using a lesser number of component items. CONSTITUTION: Relief valves 181 , 182 are furnished on relief paths 161 , 162 which generate a condition where connection parts 141 , 142 of returning hydraulic pressure paths 81 , 82 to the main liquid pressure paths 41 , 42 are connected to a reservoir R in the condition that control valves 171 , 172 shut a master cylinder M from the connection parts 141 , 142 of the returning liquid pressure paths, and the routes between pumps 101 , 102 and the second solenoid valves 91 , 92 of the returning liquid pressure paths 81 , 82 are connected to the reservoir R through normally closed solenoid valves 201 , 202 .

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a main hydraulic passage connected to an output port of a master cylinder equipped with a reservoir.
The first solenoid valve is connected to the wheel brake via the first solenoid valve that is open when the brake fluid pressure is not controlled, and the second solenoid valve that is closed when the brake fluid pressure is not controlled and the second solenoid valve that is closed. The present invention relates to a brake device for a vehicle, in which a return pump is provided in a return hydraulic passage whose one end is connected between wheel brakes and the other end is connected to a main hydraulic passage.

[0002]

2. Description of the Related Art Conventionally, such a brake device is already known, for example, from Japanese Utility Model Laid-Open No. 3-13268.

[0003]

In the above-mentioned conventional brake device, the wheel is operated by switching the excitation / demagnetization of the normally open solenoid valve which is the first solenoid valve and the normally closed solenoid valve which is the second solenoid valve during braking operation. The brake fluid pressure acting on the brake is controllable, and antilock brake control is performed when there is a possibility of wheel lock. However, between the second electromagnetic valve and the return pump in the return hydraulic pressure path, the difference between the amount of hydraulic fluid recirculated by the return pump and the amount of hydraulic fluid flowing out of the wheel brake due to the opening of the second electromagnetic valve is absorbed. A separate reservoir is needed in addition to the reservoir attached to the master cylinder. Further, when the second solenoid valve leaks when the first and second solenoid valves are in a non-controlled state, that is, when the brake fluid pressure is not controlled and the second solenoid valve leaks, the hydraulic pressure of the wheel brake is stored between the second solenoid valve and the return pump. Flows to. Moreover, depending on the opening / closing operation of the second solenoid valve, kickback occurs in the brake pedal connected to the master cylinder, or the brake pedal is inserted, so that the brake operation feeling is inferior.

By the way, in the above-mentioned conventional brake device, the brake fluid pressure can be controlled when the brake is operated, but in addition to that, the fluid pressure is applied to the wheel brakes when the brake is not operated to perform traction control or automatic control. There is a desire to perform brake control, and in responding to such demand, it is desirable to avoid complicating the configuration.

The present invention has been made in view of such circumstances, and aims to improve the compensation and the brake operation feeling when a leakage occurs in the second solenoid valve, and to have a simple construction with a small number of parts. An object of the present invention is to provide a vehicle brake device that enables brake control during non-brake operation.

[0006]

In order to achieve the above object, according to the present invention, a main hydraulic passage connected to an output port of a master cylinder having a reservoir is set to an open state when the brake hydraulic pressure is not controlled. Is connected to the wheel brake via the first solenoid valve, and one end is connected between the first solenoid valve and the wheel brake via the second solenoid valve that is closed when the brake fluid pressure is not controlled. In a vehicle brake device in which a return pump is provided in the return hydraulic passage whose end is connected to the main hydraulic passage, the main hydraulic pressure is provided between the connection portion of the return hydraulic passage to the main hydraulic passage and the master cylinder. The passage is provided with a control valve that is normally in communication with the master cylinder and the connecting portion, which can be shut off.
A relief valve is provided in a relief passage that connects the connection portion to the reservoir when at least the control valve shuts off the connection between the master cylinder and the connection portion, and the relief valve is provided between the second solenoid valve and the return pump in the return hydraulic passage. Is connected to the reservoir via a normally closed solenoid valve.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

1 to 3 show an embodiment of the present invention. FIG. 1 is a vehicle brake hydraulic circuit diagram, FIG. 2 is a sectional view of a modulator, and FIG. 3 is a pressure reducing characteristic diagram of the modulator. .

First, in FIG. 1, a brake operating force input from a brake pedal 1 is amplified by a negative pressure booster 2 and input to a tandem type master cylinder M, and a pair of output ports 3 ₁ provided in the master cylinder M. , the brake fluid pressure according to 3 ₂ to the brake operating force is outputted.

[0010] the main liquid passage 4 to one output port 3 _1
1 is connected, and this main hydraulic passage 4 ₁ is connected to the right rear wheel brake B _RR via a normally open solenoid valve 6 ₁ as a first solenoid valve, and also via a modulator 5 _1. Connected to left front wheel brake B _FL . A main hydraulic passage 4 ₂ is connected to the other output port 3 ₂ , and this main hydraulic passage 4 ₂ is a normally open solenoid valve 6 as a first solenoid valve.
It is connected to the left rear wheel brake B _RL via ₂ and
Is connected to the right front wheel brake B _FR through the modulator 5 _2.

Double normally open solenoid valve 6₁, 6₂On the right rear wheel
Rake B_RRAnd left rear wheel brake B _RLOf hydraulic fluid from the side
Check valve 7 that allows only distribution₁, 7₂Connected in parallel
Is done. Also, normally open solenoid valve 6₁And right rear wheel brake B
_RRAnd normally open solenoid valve 6₂And left rear wheel brake
B_RLBetween them is a normally closed solenoid valve 9 as a second solenoid valve.₁, 9
₂Return hydraulic line 8 via₁, 8₂One end of is connected
And the return hydraulic line 8₁, 8₂The other end of the main hydraulic line
4₁, 4₂Connected to. Moreover, each return hydraulic passage 8₁, 8
₂The return pump 10₁, 10₂And return pump 10
₁, 10₂Check that allows only the working fluid to flow from the side
Ku valve 11₁, 11₂Is a normally closed solenoid valve 9₁, 9₂Side
It is provided in order. Double return pump 10₁, 10₂Is
The return pump 1 is driven by a common motor 12.
0₁, 10₂And check valve 11₁, 11₂Back in between
Hydraulic path 8₁, 8₂Damper 13₁, 13₂Is connected
It

Return hydraulic pressure passage 8 to the main hydraulic pressure passages 4 ₁ and 4 ₂ .
Connection parts 14 ₁ and 14 _{2 of 1} and 8 ₂ and a normally open solenoid valve 6 ₁ ,
The main hydraulic pressure line 4 ₁ between the 6 _2, 4 ₂ and return fluid pressure passage _81, 82 normally closed solenoid valve 9 ₁ in _2, 9 ₂ and return between the pump 10 _1, 10 ₂ between Is a check valve 15 ₁ ,
Check valves 1 connected through 15 ₂
5 ₁ and 15 ₂ allow only the flow of the hydraulic fluid from the return hydraulic pressure passages 8 ₁ and 8 ₂ side toward the main hydraulic pressure passages 4 ₁ and 4 ₂ .

A reservoir R is attached to the master cylinder M, and the reservoir R has relief paths 16 ₁ , 16.
₂ is connected. Thus were the main liquid passage 4 _1, 4 return fluid pressure passage _81, the 8 _second connection portion 14 ₁ to _2, 14 _2, the 3-port 2-position solenoid switching valve 17 _1, 17 ₂ as a control valve , Is normally in communication with the output ports 3 ₁ , 3 ₂ of the master cylinder M, but the 3-port 2-position solenoid switching valve 1
The excitation of 7 ₁ and 17 ₂ cuts off the connection with the output ports 3 ₁ and 3 ₂ and switches the communication to the relief paths 16 ₁ and 16 ₂ . That is, the 3-port 2-position electromagnetic switching valves 17 ₁ and 17 ₂ are connected to the connecting portion 1 in the demagnetized state.
4 ₁ , 14 ₂ are output ports 3 ₁ , 3 of the master cylinder M
₂ but is in a state of being cut off from the relief paths 16 ₁ and 16 ₂ and being excited, the connecting portions 14 ₁ and
14 ₂ to switching operation to the output port 3 _1, 3 ₂ relief passage 16 ₁ and disconnected from, 16 ₂ to communication with the master cylinder M.

Relief path 16₁, 16₂On relief valve
18₁, 18₂Are provided respectively.
Leaf valve 18₁, 18₂Is a 3-port 2-position solenoid switching valve
17 ₁, 17₂Is the connection part 14₁, 14₂The relief road 1
6₁, 16₂When in the state of being connected to
4₁, 14₂Open when the hydraulic pressure on the side exceeds a specified value
Then, the connection part 14₁, 14₂Reservoir from the side
It works to let R escape.

In the return hydraulic pressure passages 8 ₁ and 8 ₂ , suction passages 19 ₁ and 19 ₂ connected to the reservoir R are connected between the normally closed solenoid valves 9 ₁ and 9 ₂ and the return pumps 10 ₁ and 10 _2. And these suction paths 19 ₁ , 19 ₂
Are provided with normally closed solenoid valves 20 ₁ and 20 ₂ , respectively.

The modulators 5 ₁ and 5 ₂ have the same structure. Hereinafter, only the structure of the modulator 5 ₁ will be described in detail with reference to FIG. 2, and the detailed description of the structure of the modulator 5 ₂ will be omitted. To do.

In FIG. 2, the modulator 5 ₁ comprises a pressure reducing control valve 22 and a linear solenoid 23.

In the housing 24 of the decompression control valve 22, an output chamber 25, a release chamber 27 with a partition wall 26 interposed between the output chamber 25, and a sliding member having one end connected to the release chamber 27. A hole 28 and a working chamber 29 having a diameter larger than that of the sliding hole 28, one end of which is coaxially connected to the other end of the sliding hole 28 and the other end of which is open, are provided. The provided linear solenoid 23 is attached to the housing 24 such that the drive rod 23a is coaxially arranged in the working chamber 29 and the outer end of the working chamber 29 is closed.

A spool valve element 30, one end of which faces the release chamber 27, is slidably fitted into the slide hole 28, and the open chamber 2 is opened.
A return spring 31 is contracted between one end of the spool valve element 30 and the partition wall 26 within the valve 7. The spring force of the return spring 31 causes the spool valve element 30 to move the other end to the drive rod 2.
It is urged so as to always come into contact with 3a.

A reaction force pin 32 having a diameter smaller than that of the spool valve body 30 is penetrated through the partition wall 26 in a liquid-tight and slidable manner, and one end of the reaction force pin 32 facing the output chamber 25 and the housing. A spring 33, which exerts a weak spring force to the extent that the other end of the reaction force pin 32 is always in contact with one end of the spool valve body 30, is contracted between the spring 33 and 24.

The sliding hole 28 is provided with a first annular recess 34 on the release chamber 27 side and a second annular recess 35 on the working chamber 29 side at an axial interval. Recess 3
A communication passage 36 is provided in the housing 24, one end of which is opened at the inner surface of the slide hole 28 between the No. 4 and 35, and the other end of the communication passage 36 is communicated with the output chamber 25. Further, the spool valve body 30 is provided with an annular groove 37, which communicates the second annular recess 35 with the communication passage 36 when the spool valve body 30 is in the retracted position as shown in FIG. However, the first annular recess 34 is blocked from the communication passage 36, and when the spool valve body 30 advances, the first annular recess 34 is communicated with the communication passage 36, but the second annular recess 35 is blocked from the communication passage 36.

In the housing 24, the return hydraulic passage 8 is communicated with the release chamber 27 and the first annular recess 34, respectively.
_1, 8 and ₂ of the first and second release port 38 and 39 are communicated with the common one end, an input port 40 which communicates with the main liquid passage 4 _1, 4 ₂ with communicating with the second annular recess 35
And an output port 41 leading to the output chamber 25 and leading to the left and right front wheel brakes B _FL and B _FR .

The linear solenoid 23 applies an axial thrust corresponding to the applied current from the drive rod 23a to the spool valve body 30, and the spool valve body 30 is connected to the communicating path by the axial thrust from the linear solenoid 23. 36, that is, the output chamber 25, is pressed in the direction of communicating with the first annular recess 34, that is, the second release port 39. On the other hand, the spool valve body 30 is provided with a spring force that opposes the axial thrust by the return spring 31, and the hydraulic pressure of the output chamber 25 acts on the reaction force pin 32 to cause the reaction force from the reaction force pin 32. A force will be exerted against the axial thrust. In this way, the spool valve body 30
Communicates the output chamber 25, that is, the output port 41, with the second annular recess 35, that is, the input port 40, so that the thrust of the linear solenoid 23 and the spring force of the return spring 31 and the reaction force from the reaction force pin 32 are balanced. The retracted position to
It moves in the sliding hole 28 between the forward position where the output port 41 communicates with the input port 40, and as a result, the hydraulic pressure input from the input port 40 is applied to the linear solenoid 23 as shown in FIG. The liquid pressure reduced in accordance with the increase in the amount is output from the output port 41.

Such a modulator 5₁, 5₂Then
First annular recess of the second annular recess 35 in the pressure reducing control valve 22
The edge of the portion 34 side and the linear groove 23 side of the annular groove 37
The edge means the first solenoid valve 22._I1, 22_I2Make up. sand
The left and right front wheel brake B_FL, B_FRBrake fluid pressure
When the linear solenoid 23 is not controlled,
Sometimes, the main hydraulic line 4₁, 4₂Second ring leading to
-Shaped recess 35 is communicated with the communication passage 36 through the annular groove 37.
The first solenoid valve 22_I1, 22_I2Is in the valve open state,
The path 36 is on the left via the output chamber 25 and the output port 41.
And right front wheel brake B_FL, B_FRBe communicated to. Decompression
The second annular recess 3 of the first annular recess 34 in the control valve 22.
The 5th side edge and the linear solenoid 23 of the annular groove 37 are opposite to each other.
The opposite edge means the second solenoid valve 22._O1, 22_O2Make up
It Ie left and right front wheel brake B_FL, B_FRBlur
The linear solenoid 23 turns off when the hydraulic pressure is not controlled.
When in the magnetic state, the return hydraulic pressure passage 8₁, 8₂At one end of
The first annular recess 34 that communicates with the annular groove 37 is blocked from the first annular recess 37.
2 Solenoid valve 22_O1, 22_O2Is closed and the return hydraulic line
8₁, 8₂One end of the first solenoid valve 22_I1, 22_I2And left
And right front wheel brake B _FL, B_FRSecond solenoid valve 22 between
_O1, 22_O2Will be connected via.

Referring again to FIG. 1, the modulator 5₁, 5
₂Output ports 41, 41 of the left front wheel brake B_FLAnd
And right front wheel brake B_FREach connected to
Allows only working fluid to flow from the output ports 41, 41
Check valve 42₁, 42 ₂Through main hydraulic line 4
₁, 4₂Connection part 14₁, 14₂And normally open solenoid valve 6
₁, 6₂Connected in between.

Next, the operation of this embodiment will be described. During normal braking without the antilock brake control and the braking force distribution control, the motor 12, that is, the return pumps 10 ₁ and 10 ₂ are stopped and the normally open type. The solenoid valves 6 ₁ and 6 ₂ are demagnetized and are in the open state, and the normally closed solenoid valves 9 ₁ and 9 ₂ are demagnetized and are in the open state, and the 3-port 2-position solenoid switching valves 17 ₁ and 17 ₂ are The output ports 3 ₁ , 3 ₂ are demagnetized to communicate with the main hydraulic paths 4 ₁ , 4 ₂ , and the normally closed solenoid valves 20 ₁ , 20 ₂ are demagnetized and are in a closed state. Further, no current is applied to the linear solenoids 23 of the modulators 5 ₁ and 5 ₂ , the first solenoid valves 22 _I1 and 22 _I2 are in the open state, and the second solenoid valve 2
₂₀₁ and 22 _O2 are closed. When the brake pedal 1 is operated in this state, the hydraulic pressure output from the output ports 3 ₁ and 3 _{2 of the} master cylinder M is transferred from the main hydraulic pressure passages 4 ₁ and 4 ₂ to the normally open solenoid valves 6 ₁ and 6 2. together acting respectively on the right rear wheel brake B _RR and a left rear wheel brake B _RL via _2, modulator 5 _1, 5 ₂ of the first solenoid valve 2
It acts on left front wheel brake B _FL and right front wheel brake B _FR via 2 _I1 and 22 _I2 , respectively.

When the normally closed solenoid valves 9 ₁ , 9 ₂ or the second solenoid valves 22 _O1 , 22 _O2 leak during such normal braking, the normally closed solenoid valves 20 ₁ , 20 ₂ are demagnetized / demagnetized. Since the valve is closed, the leaked hydraulic fluid does not flow to the reservoir R.

Next, the braking force distribution control or
When executing the chillock brake control, the normally closed type
Solenoid valve 20₁, 20₂By energizing and opening the valve
Sushi pump 10₁, 10₂When communicating with the reservoir R
Monomotor 12 or return pump 10₁, 10₂Made
3 port 2-position solenoid switching valve 17₁, 1
7₂The output port 3 of the master cylinder M₁,
Three₂And the connecting portion 14 ₁, 14₂Cut off the space. This state
State, modulator 5₁, 5₂Linear solenoid 23
By individually controlling the current applied to the return pump
10₁, 10₂Output hydraulic pressure of modulator 5₁, 5₂so
Adjust each one, then left front wheel B_FLAnd right front wheel blur
Key B_FRIt is possible to control each brake pressure individually.
It Also, normally open solenoid valve 6₁And normally closed solenoid valve 9₁Encouragement of
Switching between depressurization, holding and boosting by controlling magnetism and demagnetization
Rear right wheel brake B_RRCan control the brake pressure of
Yes, normally open solenoid valve 6₂And normally closed solenoid valve 9₂Excitation of
・ Switching between decompression, holding and boosting by controlling demagnetization
Left rear wheel brake B_RLIt is possible to control the brake pressure of
Wear. At this time, the return pump 10₁, 10₂Pulse to the discharge pressure of
Damper 13 even if there is movement₁, 13₂In that discharge pulse
The movement is damped.

Such braking force distribution control or
When the lock lock brake control is executed, the connecting portion 14₁, 1
4₂Relief valve 18 when the hydraulic pressure of₁,
18 ₂When the valve is opened, excess hydraulic fluid is stored in the reservoir R
Returned to.

Also, braking force distribution control or anti-lock
At the end of the brake control, modulator 5₁, 5
₂The current application to the linear solenoid 23 of
Modulator 5₁, 5₂Input port 4 at
No hydraulic pressure difference between 0 and output port 41
3 port 2 position solenoid switching valve 17₁, 17₂Disappears
Is magnetized, which results in the connection 14₁, 14₂Is Master Siri
Output port 3 of the M ₁, 3₂Be communicated to. Accordingly
Master cylinder M output fluid pressure and left front wheel brake B_FL
And right front wheel brake B_FRIs the same as the fluid pressure of
, Kickback of the brake pedal 1 may occur,
The brake pedal 1 will not get in. Well
Right rear wheel brake B_RRAnd left rear wheel brake B_RLRegarding
Normally open solenoid valve 6₁, 6₂And normally closed solenoid valve
9₁, 9₂It is difficult to control fine pressure by
Port 2 position solenoid switching valve 17₁, 17₂Normally open after excitation
Type solenoid valve 6₁, 6₂Is demagnetized, opened and normally closed
Solenoid valve 9₁, 9₂Is demagnetized and closed. Do this
And the output hydraulic pressure of the master cylinder M and the left front wheel brake B
_FLAnd right front wheel brake B_FRThere is a slight difference with the hydraulic pressure of
The kickback and entry of the brake pedal 1
It occurs, but the right rear wheel brake B_RRAnd left rear wheel brake B
_RLSince the cylinder volume of is small, the brake pedal 1 key
Small back and intrusion, no problem
Yes. In addition, 3 port 2 position solenoid switching valve 17₁, 17 ₂Encouraged
When magnetized, the return pump 10₁, 10₂Stop working
Normally closed solenoid valve 20₁, 20₂Is degaussed
The valve is closed.

At the end of braking, the right rear wheel brake B _RR
And the hydraulic fluid on the left rear wheel brake B _RL side is the check valve 7
The hydraulic fluids on the left front wheel brake B _FL and the right front wheel brake B _FR side are returned to the master cylinder M side by ₁ and 7 ₂ , and are returned to the master cylinder M side by the check valves 42 ₁ and 42 ₂ . In addition, the normally closed solenoid valve 9 in the return hydraulic lines 8 ₁ , 8 _2
1 , 9 ₂ and between the second solenoid valves 22 _O1 and 22 _O2 and the return pumps 10 ₁ and 10 ₂ , and the suction passage 19 ₁ ,
19 normally closed solenoid valve 20 ₁ in the _2, 20 ₂ and the return hydraulic pressure passage _81, the hydraulic fluid between 8 _2, the check valve 15 _1, 1
By 5 ₂ is returned to the master cylinder M side.

Further, the 3-port 2-position electromagnetic switching valve 17 ₁ , 1
7 ₂ remains demagnetized, that is, the output ports 3 ₁ , 3 _{2 of the} master cylinder M remain in communication with the connection parts 14 ₁ , 14 ₂ and the return pumps 10 ₁ , 10 ₂ are stopped, and the modulator 5 The anti-lock brake control of the left front wheel brake B _FL and the right front wheel brake B _FR is performed by the hydraulic control by ₁ , 5 ₂ , and the normally open solenoid valves 6 ₁ , 6 ₂ and the normally closed solenoid valves 9 ₁ , 9 ₂ are operated. It is also possible to perform antilock brake control of the right rear wheel brake B _RR and the left rear wheel brake B _RL by the excitation / demagnetization switching control.

Perform brake operation by the brake pedal 1.
Detects the possibility of a collision with a vehicle ahead without touching
Always perform automatic brake control with
Closed solenoid valve 20₁, 20₂Is excited and the valve is opened.
Return pump 10₁, 10₂Communicates with reservoir R
With return pump 10₁, 10₂To activate
3 port 2 position solenoid switching valve 17₁, 17₂Is excited
Output port 3 of master cylinder M₁, 3₂And connection
Part 14₁, 14₂The space is cut off. In this state,
Lator 5₁, 5₂Applied to the linear solenoid 23
By controlling the return pump 10₁, 10₂Out of
Hydraulic pressure is modulator 5₁, 5₂Respectively adjusted with
Front left wheel brake B_FLAnd right front wheel brake B_FRDesired by
The braking force can be exerted. At this time, the right rear wheel
Key B_RRAnd left rear wheel brake B _RLAlso in the normally open type
Solenoid valve 6₁, 6₂And normally closed solenoid valve 9₁, 9₂Excitation of
・ Provides desired braking force by controlling demagnetization
It is possible to

In addition, the traction of the drive wheels in the non-brake operation state
The above automatic brake control
Return pump 10 as well₁, 10₂Reservoir R
It is operated in the state of communicating with the
Position solenoid switching valve 17₁, 17 ₂Master cylinder M
Output port 3₁, 3₂And the connecting portion 14₁, 14₂while
Shut off. When the left and right front wheels are the driving wheels
Normally open solenoid valve 6₁, 6₂Is excited and closed
Modulator 5₁, 5₂The hydraulic pressure controlled by
Key B_FLAnd right front wheel brake B_FRTo act on
This makes it possible to brake the left and right drive wheels.
It When the left and right rear wheels are the driving wheels, the linear
Modulator 5 with maximum applied current to Renoid 23
₁, 5₂Shut off, and the normally open solenoid valve 6₁, 6
₂And normally closed solenoid valve 9₁, 9₂Excitation / demagnetization switching control
The hydraulic pressure adjusted by the controller is the right rear wheel brake B._RRand
Left rear wheel brake B_RLOn the left,
The right drive wheel can be braked.

To end the brake control during non-brake operation, the normally open solenoid valves 6 ₁ , 6 ₂ ,
Normally closed solenoid valves 9 ₁ , 9 ₂ , 3-port 2-position solenoid switching valve 1
7 _1, 17 ₂ and the normally closed electromagnetic valves 20 _1, 20 ₂ back motor 12 i.e. while all demagnetized pump 10 _1, 10 ₂ may be stopped.

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, a 3-port 2-position solenoid switching valve 1
Instead of 7 ₁ , 17 ₂ , a normally open solenoid valve may be provided between the output ports 3 ₁ , 3 _{2 of the} master cylinder M and the connection parts 14 ₁ , 14 ₂ , and in that case, the relief valve 18
_The relief channels 16 ₁ , 16 ₂ with ₁ , 18 ₂ are connected to the connection parts 14 ₁ , 14 ₂ .

[0038]

As described above, according to the present invention, between the connection portion of the return hydraulic pressure passage to the main hydraulic pressure passage and the master cylinder, the main hydraulic pressure passage is provided between the master cylinder and the connection portion. A control valve is provided that is normally open so that it can be shut off. At least when the control valve shuts off the connection between the master cylinder and the connecting portion, the connecting portion is connected to the reservoir. With a simple configuration in which a valve is provided and the second solenoid valve and the return pump in the return hydraulic line are connected to the reservoir via a normally closed solenoid valve, traction control and automatic brake control during non-brake operation can be performed. It becomes possible to do it. Further, even if there is a leak in the second solenoid valve between the wheel brake and the return hydraulic passage, it can be compensated by the normally closed solenoid valve, and a reservoir is provided between the second solenoid valve in the return hydraulic passage and the return pump. It is not necessary to provide it, and it is not necessary to provide a hydraulic pressure source for performing the above-mentioned traction control or automatic brake control, so that the number of parts can be reduced. Furthermore, it is possible to improve the feel of brake operation by avoiding kickback and brake pedal entry as much as possible during brake operation.

[Brief description of drawings]

FIG. 1 is a brake hydraulic circuit diagram of a vehicle.

FIG. 2 is a cross-sectional view of a modulator.

FIG. 3 is a pressure reduction characteristic diagram of a modulator.

[Explanation of symbols]

4 ₁ , 4 ₂ ... Main hydraulic passage 6 ₁ , 6 ₂ ... Normally open type solenoid valve as _first solenoid valve 8 ₁ , 8 ₂ ... Return hydraulic passage 9 ₁ , 9 ₂ ... -Normally closed solenoid valve as second solenoid valve 10 ₁ , 10 ₂ ... Return pump 14 ₁ , 14 ₂ ... Connection portion 16 ₁ , 16 ₂ ... Relief path 17 ₁ , 17 ₂ ... 3-port 2-position solenoid directional control valve 18 ₁ , 18 ₂ ... Relief valve 20 ₁ , 20 ₂ ... Normally closed solenoid valve 22 _I1 , 22 _I2 ... First solenoid valve 22 _O1 , 22 _O2・ ・ ・ Second solenoid valve B _FL・ ・ ・ Left front wheel brake as wheel brake B _FR・ ・ ・ Right front wheel brake as wheel brake B _RL・ ・ ・ Left rear wheel brake as wheel brake B _RR・ ・ ・Right rear wheel brake as a wheel brake M ... Master cylinder R ... Reservoir

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Wataru Saito 1-4-1 Chuo, Wako-shi, Saitama, Ltd. Honda R & D Co., Ltd.

Claims (1)

[Claims] 1. A master cylinder comprising a reservoir (R)
(M) output port (3₁, 3₂) Connected to the main
Hydraulic path (4₁, 4₂), When the brake fluid pressure is not controlled
The first solenoid valve (22_I1, 22_I2, 6₁, 6
₂) Via the wheel brake (B_FL, B_FR, B_RR, B_RL)
Is closed and the valve is closed when the brake fluid pressure is not controlled.
Second solenoid valve (22_O1, 22_O2, 9₁, 9₂) Through
Then the first solenoid valve (22_I1, 22_I2, 6₁, 6₂)and
Wheel brake (B_FL, B_FR, B _RR, B_RL) One end touches
The main hydraulic passage (4₁, 4₂) To
Return hydraulic line connected (8₁, 8₂), Return pump
(10₁, 10₂) Is provided in the vehicle brake device
In the main hydraulic line (4₁, 4₂) Return hydraulic line to
(8₁, 8₂) Connection part (14₁, 14₂) And Masashi
Main fluid pressure path (4₁, 4₂) To
Is the master cylinder (M) and the connecting portion (14₁,
14₂) It is possible to cut off the space between
Control valve (17)₁, 17₂) Is provided and at least
The control valve (17₁, 17₂) Is the master cylinder (M)
And the connection part (14₁, 14₂) Between
Then, the connection part (14₁, 14₂) To the reservoir (R)
Relief path (16 connected)₁, 16₂)
Leaf valve (18₁, 18₂) Is provided and the return hydraulic line
(8₁, 8₂) Second solenoid valve (22_O1, 22_O2, 9₁,
9₂) And return pump (10 ₁, 10₂) Is normally closed
Type solenoid valve (20₁, 20₂) To the reservoir (R)
A vehicle braking device characterized by being connected.