JPH0331619B2 - - Google Patents

Description

[Detailed Description of the Invention] A. Purpose of the Invention (1) Industrial Application Field The present invention is a vehicle braking system in which a dual master cylinder is used to configure two independent braking hydraulic circuits. Braking hydraulic control device in the device,
In particular, the present invention relates to a brake hydraulic pressure control device that supplies a hydraulic pressure lower than that of the front wheels as the rear wheel brake hydraulic pressure.

(2) Prior Art Conventionally, as shown in Fig. 1, braking devices for vehicles have been equipped with two types of braking devices:
Mutually independent first and second flow paths L ₁ and L ₂ extending from the output side of the dual master cylinder M are connected to the hydraulic operating parts of the rear wheel brakes Bf, Br' and Bf', Br, respectively. There is a format that does this. In this type of braking system, during heavy braking, each rear wheel brake hydraulic pressure is automatically reduced at a fixed ratio to the front wheel brake hydraulic pressure of the same system, and the load on the rear wheels is reduced by tilting the vehicle forward. In order to obtain efficient braking even when the vehicle is in use, a common brake hydraulic control device C is provided between the first and second flow paths L ₁ and L ₂ on the way to the rear wheel brakes Br and Br′. is known, and the device C includes a common housing interposed in the middle of the first and second flow paths, a pair of left and right pressure receiving pistons that slide into cylinder holes in the housing, and these pressure receiving pistons. A first and second input hydraulic chambers are connected to the upstream side of the first and second flow paths, and a first input hydraulic pressure chamber is connected to the downstream side of the first and second flow paths, and a first input hydraulic pressure chamber is connected to the downstream side of the first and second flow paths. and a second output hydraulic chamber, and the pressure receiving area of each output hydraulic chamber side of each pressure receiving piston is larger than the pressure receiving area of each input hydraulic chamber side,
Adjacent input and output hydraulic chambers are communicated via valves that open at the outward sliding limit of each of the pressure receiving pistons and close when they slide inward, and common pressure regulation is established between both the pressure receiving pistons. It has a structure with a compressed spring.

(3) Problems to be Solved by the Invention Incidentally, a coil spring is generally used as the pressure regulating spring, and even if there is some error in the length of the pressure regulating spring in the installed state, the pressure receiving piston The spring length is set sufficiently long and the spring constant is set as small as possible so that there is no large deviation in the timing at which the pressure reduction action starts. Nevertheless, in conventional brake hydraulic control devices, this long pressure regulating spring is compressed between the opposing inner ends of a pair of pressure receiving pistons, so the gap between both pressure receiving pistons becomes large, resulting in There is a drawback that the axial length of the device becomes long, making the device large.

In addition, in the above conventional device, if the space sandwiched between the inner ends of both pressure receiving pistons and housing the pressure regulating spring is made into a closed space to avoid intrusion of dust, etc., when the pressure receiving piston operates, the space in which the pressure regulating spring is housed is closed. Since there is a risk that smooth operation may not be possible due to air compression resistance within the piston, it is necessary to widen the gap between the two pressure receiving pistons in order to avoid such a problem, and the above-mentioned drawback becomes even more noticeable.

The present invention was proposed in view of the above circumstances, and it is possible to provide a coiled pressure regulating spring with a large length and diameter in order to set the spring constant as low as possible, and also to reduce the space between both pressure receiving pistons. The above-mentioned high-performance and compact braking hydraulic control system is capable of reducing the distance between both pressure receiving pistons to the necessary minimum while minimizing the air compression resistance in the space when the pressure receiving piston is operated even when the pressure receiving piston is operated as a closed space. The purpose is to provide equipment.

B. Structure of the Invention (1) Means for Solving the Problems In order to achieve the above object, the present invention provides a system for separately supplying the output hydraulic pressure of a dual master cylinder to the hydraulic operating parts of a pair of left and right rear wheel brakes. A common housing is interposed between the first and second flow paths, and the cylinder hole in the housing has an outer sliding limit by bringing the outer end surface into contact with the outer end wall of the cylinder hole. A pair of left and right pressure receiving pistons to be regulated are slidably fitted, and first and second input hydraulic pressure chambers are provided on the inner end sides of these pressure receiving pistons and respectively communicate upstream of the first and second flow paths. Also, on the outer edge side,
first and second channels that communicate separately downstream of both flow paths;
In addition to forming output hydraulic chambers, the pressure receiving area on the output hydraulic chamber side of each pressure receiving piston is made larger than the pressure receiving area on the input hydraulic chamber side, and the pressure receiving area of each pressure receiving piston is made to be larger than the pressure receiving area on the input hydraulic chamber side. Each adjacent input and output hydraulic chamber is communicated through a valve that opens when it comes into contact with the outer end wall of each cylinder hole and closes when the pressure receiving piston slides inward, and communicates between the two pressure receiving pistons. In a brake hydraulic pressure control device for a vehicle braking device, which has a common coiled pressure regulating spring compressed therebetween, the mating surface is positioned between a pair of cylinder holes into which the pair of pressure receiving pistons are respectively fitted. , the housing is composed of a pair of housing halves that are connected to each other, and a large-diameter hole extending across the housing halves and having a larger diameter than the cylinder hole is formed in both housing halves. On the other hand, shoulders facing the large diameter hole and facing each other are formed on the outer peripheries of the axially intermediate portions of the pair of pressure receiving pistons, so that an external A more closed spring chamber is defined, and in this spring chamber, the spring chamber is compressed between a pair of washers that abut on opposing surfaces of the shoulder portions, and is formed to have a larger diameter than the cylinder hole. A pressure regulating spring is housed therein, and each of the washers and the pressure regulating spring cooperates with the outer end wall of each cylinder hole to clamp each pressure receiving piston at the outer sliding limit of each of the pressure receiving pistons. A gap is provided between the inner end surface of the large-diameter hole and the corresponding large-diameter hole.

(2) Effect According to the above configuration, the pressure regulating spring can be given a large length and diameter without being restricted by the pair of pressure receiving pistons and their cylinder holes, and its spring constant can be set sufficiently low. , changes in the set load of the pressure regulating spring are kept small, and a stable pressure regulating function can always be obtained. On the other hand, the pair of pressure-receiving pistons can be arranged close to each other with a necessary minimum axial spacing without being interfered with by the pressure regulating spring.

In addition, by closing the spring chamber housing the pressure regulating spring from the outside, it is possible to suppress the intrusion of dust, etc. into the spring chamber, and furthermore, the effective volume of the spring chamber can be reduced by Since this can be sufficiently ensured by the special arrangement of the hole and the opposing shoulders, the compression resistance of the air in the spring chamber, which the pressure receiving piston experiences during its operation, is reduced.

In addition, especially at the outward sliding limit of each pressure receiving piston, a gap is set between each washer and the corresponding large diameter hole inner end surface, so between the outward sliding limit of the pressure receiving piston and the outward movement of the valve. The limits are regulated using the outer end wall of the cylinder hole as a common reference surface, and the opening/closing stroke of the valve can be set with high precision. Furthermore, the washer can be easily assembled by simply bringing it into contact with the pressure-receiving piston shoulder.

Furthermore, by dividing the housing into two as described above, it is possible to easily process the large diameter hole and assemble the pressure regulating spring therein.

(3) Embodiment Hereinafter, an embodiment of the present invention will be explained with reference to the drawings. The dual master cylinder M is configured in a tandem type as shown in FIG. A pair of front and rear pistons 2 ₁ and 2 ₂ serve as first and second output ports, respectively.
Pressure oil can be supplied from P ₁ and P ₂ to the first and second flow paths L ₁ and L ₂ . This pressure oil is led to the front wheel brakes Bf, Bf' and the brake hydraulic control device C.

The brake hydraulic control device C is configured symmetrically, and its housing is connected to a pair of left and right first and second housing halves 3 ₁ and 3 ₂ via flanges 4 ₁ and 4 ₂ to bolts 5 and nuts 6. are mutually joined by. Each housing half 3 ₁ , 3 ₂ has a cylinder hole 7 ₁ , 7 ₂ and a large diameter hole 8 ₁ , which has a larger diameter than the cylinder hole 7 1 , 7 2 .
8 ₂ are formed, and each cylinder hole 7 ₁ , 7 ₂
Pressure receiving pistons 9 ₁ and 9 ₂ having the same diameter are slidably fitted into the respective pressure receiving pistons 9 _{1 and} 9 2 .
9. The minimum distance necessary for the operation of each pressure receiving piston is provided between _{the two} . Each pressure receiving piston 9 ₁ , 9 ₂
Small cylinder holes 10 ₁ and 10 ₂ of the same diameter are formed in the small cylinder holes 10 ₁ and 10 ₂ , and valve moving pistons 11 1 and 11 2 whose back surfaces are in contact with each other slide into these small cylinder holes 10 ₁ and 10 ₂ , respectively. ing. Thus, the inner surfaces of the large diameter holes 8 ₁ and 8 ₂ and both pressure receiving pistons 9 ₁ ,
A spring chamber Cs that is closed from the outside is defined between the springs 9 and ₂ , and a pressure regulating spring 12 is housed in this spring chamber Cs as described below.

Both pressure receiving pistons 9 ₁ , facing the large diameter holes 8 ₁ , 8 ₂ ,
Opposing shoulders 31 ₁ , 31 ₂ are formed on the outer periphery of the axially intermediate portion of 9 ₂ , and these shoulders 31 ₁ , 3
A common relatively strong coiled pressure regulating spring ₁₂ is compressed between the two shoulder portions 31 ₁ and 31 ₂ through washers 32 ₁ and 32 ₁ that abut the opposing surfaces of the shoulder portions 31 1 and 31 2, respectively. This pressure regulating spring 12 is formed to have a larger diameter than the cylinder holes 7 ₁ , 7 ₂ and therefore the pressure receiving piston.
In this way, the pressure regulating spring 12 is housed in the spring chamber Cs and surrounds the opposing inner ends of the pressure receiving pistons 9 ₁ and 9 ₂ .

Further, between the two valve moving pistons 11 ₁ and 11 ₂ , shoulder portions 13 ₁ and 13 ₂ of each piston 11 ₁ and 11 ₂ are provided.
and the inner and outer shoulder portions 1 of the small cylinder holes 10 ₁ and 10 ₂
A relatively weak coil-shaped positioning spring 17 is compressed through washers 16 ₁ and 16 ₂ that can abut on _{4 1} and 14 ₂ and 15 1 and 15 ₂ , respectively.

The valve moving pistons 11 ₁ and 11 ₂ have first and second input hydraulic chambers 18 ₁ and 18 ₂ in both the small cylinder holes 10 ₁ and 10 ₂ through their respective outer ends. 7 ₁ and 7 ₂ have pressure receiving pistons 9
₁ and 9 ₂ , the first and second output hydraulic chambers 1
9 ₁ and 19 ₂ are respectively defined, and these first and second input hydraulic chambers 18 ₁ and 18 ₂ have an inflow port 2.
0 ₁ , 20 ₂ via the first and second flow paths L ₁ , L ₂
The upstream side of is also the first and second output hydraulic chambers 19 ₁ ,
19 ₂ is connected via outflow ports 21 ₁ and 21 ₂ so that the downstream sides of both channels L ₁ and L ₂ are always in communication with each other.

The end walls of the small cylinder holes 10 ₁ and 10 ₂ are provided between adjacent input and output hydraulic chambers 18 ₁ and 19 ₁ and between the adjacent input and output hydraulic chambers 18 1 and 18 ₂ , 1
Communication holes 22 ₁ , 22 ₂ are provided to communicate between the valve opening rods _{24 1} , ₂₄ , which project from the outer ends of the valves _{23 1 ,} 23 ₂ , respectively. ₂ can penetrate. Each valve 23 ₁ , 23 ₂ and valve moving piston 11 ₁ ,
Closing springs 25 ₁ and 25 ₂ are respectively compressed between the valves 11 ₂ and the opening rods 24 ₁ and 24 ₂ of the valves 23 ₁ and 23 ₂ are normally connected to the outer ends of the cylinder holes 7 ₁ and 7 ₂ . The valves 23 ₁ , 23 ₂ are held in the open position by the outward sliding limit of each pressure receiving piston 9 ₁ , 9 ₂ in contact with the wall. Therefore, each pressure receiving piston 9 ₁ ,
9 ₂ is a large-diameter washer 32 ₁ , 32 ₂ that receives the pressure regulating spring 12 in a state where the outer end thereof is in the above-mentioned outward sliding limit in contact with the outer end wall of the cylinder hole 7 ₁ , 7 ₂ . hole 8 ₁ ,
The dimensions are determined so that slight gaps s ₁ and s ₂ are created between the pressure regulating spring ₁₂ and the inner end surfaces of the cylinder holes 7 1 and 7 2, so that the pressure regulating spring 12 cooperates with the outer end walls of the cylinder holes 7 ₁ and 7 ₂ . The pressure receiving pistons 9 ₁ and 9 ₂ can be held between them.

The pressure receiving pistons 9 ₁ , 9 ₂ move inward and touch the end walls of the small cylinder holes 10 ₁ , 10 ₂ and the valves 23 ₁ , 23 _{2 .}
When they come into contact with each other, the communication holes 22 ₁ and 22 ₂ are closed.

Connectors 26 ₁ and 26 ₂ are attached to the inner ends of each valve 23 ₁ and 23 ₂ , respectively. The inner ends of these connectors 26 ₁ , 26 ₂ are connected to stoppers provided at the inner ends of the valve moving pistons 11 ₁ , 11 ₂ when the pistons 11 ₁ , 11 ₂ move inward by a predetermined distance l ₂ . 27 ₁ and 27 ₂ . This distance l ₂ is equal to the distance between the valves 23 ₁ ,
The distance l 1 that the pressure receiving pistons 9 ₁ , 9 ₂ move from the valve opening position to the valve closing position of 23 ₂ is greater than the distance l ₁ and the washers 16 1 , ₁₆ with respect to this distance l ₁ and the small cylinder holes 10 ₁ , 10 ₂ . ₂ is smaller than the sum of the possible distance l and ₃ . Note that the distance l ₃ is such that the valve moving pistons 11 ₁ and 11 ₂ are connected to the small cylinder holes 10 ₁ and 1
0 ₂ , these pistons 11 ₁ , 11
_2. Either one of the seal members 33 ₁ and 33 ₂ attached to the outer periphery is the corresponding small cylinder hole 10 ₁ or 10 ₂
It is stipulated not to deviate from this.

At the joint between the two housing halves 3 ₁ and 3 ₂ ,
A small hole 28 is provided to communicate the spring chamber Cs to the outside, and a seal ring 29 is provided inside this joint to prevent dust from entering from the outside. This seal ring 29 allows hydraulic oil etc. to flow from the inside to the outside, and seal members 30 ₁ , 30 ₂ between the pressure receiving pistons 9 ₁ , 9 ₂ and the cylinder holes ₇ 1 , 7 _{2 .} If the hydraulic oil leaks into the large-diameter holes 8 ₁ and 8 ₂ due to wear and damage, the hydraulic oil will flow out through the seal ring 29 and the small hole 28, and the failure will be solved by removing the oil in the reservoir of the master cylinder M. This makes it possible to detect abnormal surface deterioration.

Next, the operation of this embodiment will be explained.
When the master cylinder M is not in operation, both the left and right pressure receiving pistons 9 ₁ and 9 ₂ are pressed to the outward sliding limit shown in the figure by the spring force of the pressure regulating spring 12 and the positioning spring 17, and the valves 23 ₁ and 23 ₂ are The valves are open, respectively, and the first and second input and output hydraulic chambers 18 ₁ , 1
9 ₁ and 18 ₂ and 19 ₂ are in communication. Therefore, when the brake pedal 1 is operated here, the output hydraulic pressure of the master cylinder M is transmitted to each downstream of the first and second flow paths L ₁ and L ₂ , and
Rear wheel brakes Bf, Bf' and Br, Br' operate simultaneously.

Then, as the output oil pressure of the master cylinder M increases, the first and second input and output oil pressure chambers 18 ₁ , 19 ₁
The pressure inside the pressure receiving pistons 9 ₁ , 19 ₂ also rises, but when the pressure reaches a certain value, the difference in the pressure receiving areas between the inner and outer ends of the pressure receiving pistons 9 ₁ , 9 _{2 increases} .
The differential hydraulic pressure acting on the pressure regulating _{spring 12} and the positioning spring 17 becomes larger than the set load of the pressure regulating spring 12 and the positioning spring 17, and the pressure receiving pistons ₉₁ and ₉₂ slide inward while compressing the pressure regulating spring 12 and the positioning spring, respectively. do. on the other hand,
At this time, since substantially equal oil pressure is applied to the outer ends of each valve moving piston 11 ₁ , 11 ₂ , these pistons 11 ₁ , 11 ₂ do not move.
The valves 23 ₁ , 23 ₂ are pressed outward by the closing springs 25 ₁ , 25 ₂ to keep the valve opening rods 24 ₁ , 24 ₂ in contact with the end walls of the cylinder holes 7 ₁ , 7 ₂ .
Therefore, when each pressure receiving piston 9 ₁ , 9 ₂ moves inward by a distance l ₁ , the valves 23 ₁ , 23 ₂ close the communicating holes 22 ₁ , 22 ₂ . During this period, the braking oil pressure for the rear wheels does not increase.

When the output hydraulic pressure of the master cylinder M further increases, the pressure within the input hydraulic chambers 18 ₁ and 18 ₂ increases, pushing each pressure receiving piston 9 ₁ and 9 ₂ outward. Therefore, the valves 23 ₁ , 23 ₂ open again, increasing the pressure in the output hydraulic chambers 19 ₁ , 19 ₂ . When this pressure reaches a certain value, the pressure receiving pistons 9 ₁ and 9 ₂ operate again, and the communication holes 22 ₁ and 22 ₂ are closed.
Stop that pressure from increasing. By repeating these actions, the braking oil pressure for each rear wheel gradually increases.

On the other hand, since the output hydraulic pressure of the master cylinder M directly acts on the front wheel brakes Bf, Bf', the front wheel braking hydraulic pressure increases rapidly as the output hydraulic pressure of the master cylinder M increases. In this way, when braking is applied strongly, the front wheel brakes Bf and Bf' are applied more strongly to the front wheel on the side where the vehicle body leans forward and the downward load increases.
Rear brake for the rear wheel on the side where the load is reduced
Since Br and Br' are operated weakly, efficient braking can be performed without causing skids in each wheel.

By the way, the pressure regulating spring 12 surrounds the inner end portions of the pair of pressure receiving pistons 9 ₁ and 9 ₂ to form the spring chamber Cs.
Since the pressure-receiving pistons 9 ₁ , 9 ₂ and their cylinder holes 7 ₁ , 7 2 are not restricted by the pressure-receiving pistons 9 1 , 9 2 and their cylinder holes 7 1 , 7 ₂ , the pressure regulating spring 12 can be given a large length and diameter, and its spring constant can be increased. can be set sufficiently low. Further, both the pressure receiving pistons 9 ₁ and 9 ₂ can be disposed close to each other in the axial direction without being interfered with by the pressure regulating spring 12 in any way.

Next, one of the systems in the brake hydraulic circuit, for example the second flow path _L2 side, breaks down and the rear wheel brake
Suppose that braking hydraulic pressure is no longer applied to the hydraulic operating part of Br′. At this time, when the brake pedal 1 is operated, the output oil pressure of the master cylinder M is changed to the first flow path _L1.
The pressure in the first input hydraulic pressure chamber 18 ₁ increases, but the pressure in the second input hydraulic pressure chamber 18 ₂ does not increase. Therefore, both the valve moving pistons 11 ₁ and 11 ₂ move rightward in the figure, and the washer 16 ₁ engages with the inner shoulder 14 ₁ of the small cylinder hole 10 ₁ . Then, the valve moving piston 11 ₁ moves the pressure receiving piston 9 ₁ inward. When the valve moving piston ₁₁₁ moves by a predetermined distance _l2 ,
The stopper 27 ₁ at its outer end engages the inner end of the connector 26 ₁ and moves the valve 23 ₁ inwardly. Since the distance l ₂ is smaller than l ₁ +l ₃ , the valve 23 ₁ is separated from the end wall of the small cylinder hole 10 ₁ during this period and maintains its open state. In this way, the valve moving piston 11 ₁ , the pressure receiving piston 9 ₁ , and the valve 23 ₁ move inward to a position where the inner end of the pressure receiving piston 9 ₁ abuts the inner end of the other pressure receiving piston 9 ₂ .

When the pressure receiving pistons 9 ₁ and 9 ₂ are in contact with each other, the valve moving piston 11 ₁ is pressed inward by the hydraulic pressure in the first input hydraulic pressure chamber 18 ₁ .
Washer 16 ₁ is inside shoulder _{14 1} of small cylinder hole 10 1
The stopper 27 ₁ of the valve moving piston 11 ₁ remains engaged with the inner end of the connector 26 ₁ . Therefore, at this time, the valve 23 ₁ opens the communication hole 22 ₁ . As a result, the output hydraulic pressure of the master cylinder M is directly transmitted to the first output hydraulic chamber ₁₉₁ , and the front and rear brakes Bf' and Br of the first flow path _L1 operate with the same strength. That is, this brake hydraulic control device C is provided with a bypass function.

In addition, in the above embodiment, the valve moving pistons 11 ₁ and 11 ₂ are configured as separate bodies, but
If there is no problem with processing accuracy, these can be integrated.

C. Effects of the Invention As described above, according to the present invention, the housings are connected to each other so that the mating surfaces are located between the pair of cylinder holes into which the pair of pressure receiving pistons are respectively fitted. The two housing halves have a large diameter hole extending between them and having a larger diameter than the cylinder hole, and the above-mentioned hole is formed on the outer periphery of the axially intermediate portion of the pair of pressure receiving pistons. A spring chamber closed from the outside is defined between the inner surface of the large diameter hole and both pressure receiving pistons by forming shoulder portions facing each other and facing the large diameter hole. A pressure regulating spring, which is compressed between a pair of washers that abut on the opposing surfaces of both shoulders and has a diameter larger than that of the cylinder hole, is housed, so that the pressure regulating spring is compressed between the pair of washers that abut on the opposing surfaces of both shoulders, and is formed to have a larger diameter than the cylinder hole. It is possible to give the pressure regulating spring a large length and diameter without being constrained, and to set its spring constant sufficiently low, thereby suppressing changes in the set load of the pressure regulating spring and ensuring stable regulation at all times. It can perform pressure functions. On the other hand, the pair of pressure-receiving pistons can be placed close to each other with the minimum required axial distance without being interfered with by the pressure regulating spring, contributing to the compactness of the brake hydraulic control device. I can do it. In addition, by closing the spring chamber housing the pressure regulating spring from the outside, it is possible to suppress the intrusion of dust, etc. into the chamber, and the effective volume of the spring chamber is limited to the area facing the large diameter hole. Since sufficient space can be secured by the special provision of both shoulders, it is possible to effectively reduce the compression resistance of the air in the spring chamber that the pressure receiving piston receives when it operates, and this allows the pressure receiving piston to operate smoothly. I can do it.

In particular, at the outer sliding limit of each pressure receiving piston, each of the washers and the corresponding large diameter hole are Since a gap is provided between the inner end surface and the outer end wall of the cylinder hole, the outward sliding limit of the pressure receiving piston and the outward moving limit of the valve are regulated using the outer end wall of the cylinder hole as a common reference plane. , the opening and closing stroke of the valve can be set with high precision, and while achieving this effect, the washer can be assembled simply by abutting it against the pressure-receiving piston shoulder. The assembly workability of the device is good. Furthermore, even if the washer is not specially fixed to the pressure receiving piston in the axial direction, the spring force of the pressure regulating spring is usually used to reliably move the pressure receiving piston to a predetermined outward sliding limit where it comes into contact with the outer end wall of the cylinder hole. Since it can be retained, there is no practical problem.

Furthermore, since the housing is divided into two as described above and the large diameter hole is formed so as to span both halves of the housing, it is impossible to process the large diameter hole and assemble the pressure regulating spring therein. Coupled with the above-mentioned effect of improving assembly work efficiency by using washers, this can greatly contribute to improving the efficiency of assembly work of the device. Furthermore, since each housing half also serves as a cover for the large-diameter hole opening of the other housing half, there is no need for a dedicated cover for the opening, so as to increase the effective volume of the spring chamber as described above. Coupled with the effect that the formed pressure receiving piston shoulder also serves as a support means for the washer, this can greatly contribute to simplifying the structure as a whole.

[Brief explanation of drawings]

FIG. 1 is a system diagram showing an example of a braking device for a vehicle, and FIG. 2 is a longitudinal sectional plan view of essential parts showing an embodiment of the device of the present invention. Br, Br′...Rear wheel brake, C...Brake hydraulic control device, M...Master cylinder, _L1 , _L2 ...First and second flow paths, _s1 , _s2 ...Gap, 3 ₁ ,3 ₂ ...
First and second housing halves constituting the housing, 7 ₁ , 7 ₂ ... cylinder hole, 8 ₁ , 8 ₂ ... large diameter hole, 9 ₁ , 9 ₂ ... pressure receiving piston, 12 ... pressure regulating spring , 18 ₁ , 18 ₂ ...first and second input hydraulic chambers,
19 ₁ , 19 ₂ ...first and second output hydraulic chambers, 22
₁ , 22 ₂ ... communication hole, 23 ₁ , 23 ₂ ... valve,
31 ₁ , 31 ₂ ... shoulders of the pressure receiving pistons 9 ₁ , 9 ₂ , 32 ₁ , 32 ₂ ... washers.

Claims (1)

[Claims] 1. A common housing in the middle of the first and second flow paths L ₁ and L _{2 for separately supplying the output hydraulic pressure of the dual master cylinder M to the hydraulic operating parts of the pair of left and right rear wheel brakes Br and Br'} . 3 ₁ and 3 ₂ are interposed, and the cylinder holes 7 ₁ and 7 ₂ in the housings 3 ₁ and 3 ₂ have an outer sliding limit by bringing the outer end surface into contact with the outer end wall of the cylinder hole. _A pair of left and right pressure receiving pistons 9 ₁ , _{9 2} that are regulated are slidably fitted, and the first and second
The first and second input hydraulic chambers 18 ₁ and 18 ₂ are connected to the upstream side of the flow paths L ₁ and L ₂ separately, and are located on the outer end side.
A first channel that communicates with the downstream of both channels L ₁ and L ₂ separately.
and second output hydraulic chambers 19 ₁ , 19 _{2 ,} respectively, and the pressure receiving area of each output hydraulic chamber 19 ₁ , 19 ₂ side of each pressure receiving piston 9 ₁ , 9 ₂ is divided into each input hydraulic chamber 1 .
It is larger than the pressure receiving area on _the 8 ₁ , _{18 2} side, and the valve opening rod 24 ₁ ,
The valve opens by contacting the outer end wall of each cylinder hole 7 ₁ , 7 ₂ via 24 ₂ , and the pressure receiving piston 9
Valve 23 ₁ , ₂ that closes when sliding inward of ₁ , 9 2
3 ₂ to each adjacent input and output hydraulic chamber 18 ₁ ,
19 ₁ ; A coiled pressure regulating spring 12 communicating between 18 ₂ and 19 ₂ and common between both the pressure receiving pistons 9 ₁ and 9 ₂ ;
In the brake hydraulic control device for a vehicle braking device, the pair of pressure receiving pistons 9 are arranged in a compressed manner.
A pair of cylinder holes _{7 1} and 9 ₂ fit into each other, respectively.
The housing is composed of a pair of housing halves 3 ₁ , 3 ₂ that are joined together so that the mating surface is located between the housing halves ₃ 1 , 3 ₂ .
3 ₂ are formed with large diameter holes 8 ₁ , 8 ₂ extending across them and having _a larger diameter than the cylinder holes _{7 1 ,} 7 _{2 .} Shoulders 31 ₁ and 31 ₂ facing each other and facing the large diameter holes 8 ₁ and 8 ₂ are formed on the outer periphery of the axially intermediate portion, respectively, so that the inner surfaces of the large diameter holes 8 ₁ and 8 ₂ and both pressure receiving pistons are formed. A spring chamber closed from the outside between 9 ₁ and 9 ₂
Cs, and this spring chamber Cs has both shoulder portions 3.
The pressure regulating spring 12 is compressed between a pair of washers 32 ₁ and 32 ₂ that abut on opposing surfaces of the cylinder holes 7 ₁ and 7 ₂ , respectively, and is formed to have a larger diameter than the cylinder holes 7 1 _and 7 ₂ . At the outward sliding limit of each pressure receiving piston 9 ₁ , 9 ₂ , the pressure regulating spring 12 cooperates with the outer end wall of each cylinder hole 7 ₁ , 7 ₂ to move each pressure receiving piston 9 ₁ , 9 ₂ , each of the washers 32 ₁ ,
A braking hydraulic control device for a vehicle braking device, characterized in that gaps s ₁ and s ₂ are provided between the inner end surfaces of the large _- diameter holes 8 ₁ and 8 ₂ corresponding thereto.