JPH082003Y2 - Two-system hydraulic braking system for automobiles - Google Patents

Description

[Detailed Description of the Invention] A. Purpose of the Invention (1) Field of Industrial Application The present invention relates to a two-system hydraulic braking system for an automobile, and more particularly, to a first and a first independent cylinders of a master cylinder. A pair of front and rear pistons that define two hydraulic chambers are accommodated, and the first and second pistons are provided on one side surface of the cylinder body.
First and second having first and second output ports of hydraulic chamber
Connecting bosses are projected, and a pair of ears protruding from one side of the housing of the rear wheel braking hydraulic control device that controls the input hydraulic pressure and outputs to the left and right rear wheel brakes are connected to these connecting bosses by union bolts. The first part is fixed to these ears.
1st and 2nd which introduce | transduce the output hydraulic pressure from a 2nd output port into the 1st and 2nd input hydraulic chamber of a rear wheel braking hydraulic control apparatus.
The present invention relates to the improvement of the one provided with each inflow port.

(2) Conventional technology Such a hydraulic braking device is already known, as disclosed, for example, in Japanese Utility Model Laid-Open No. 60-104361.

In the tandem type master cylinder in such a braking device, a stop bolt that receives the first piston at its tip is screwed to the side wall of the cylinder body in order to regulate the backward limit of the front piston.

(3) Problems to be Solved by the Invention By the way, the head of the stop bolt may be loosened when its head receives an impact force or a vibration from another object, and should be loosened and separated from the cylinder body. Then, not only the retracted position of the front piston becomes unstable, but also the hydraulic oil in the cylinder body leaks.

The present invention has been made in view of the above circumstances, and it is possible to easily prevent the collision of another object with the stop bolt and the detachment of the bolt from the cylinder body by using a rear wheel braking hydraulic control device. It is an object of the present invention to provide a two-system hydraulic braking system for an automobile.

B. Configuration of the Invention (1) Means for Solving the Problems In order to achieve the above object, the invention is a stop screwed to a side wall of a cylinder body to regulate a backward limit of a front piston of a master cylinder. A protective wall which is close to the head of the bolt and covers the head is integrally formed with the housing of the rear wheel braking hydraulic control device.

(2) Operation According to the above configuration, even if a tool or the like approaches the stop bolt during maintenance of the adjacent device, the protection wall can prevent the bolt from colliding with the stop bolt. If the stop bolt starts to slacken, the head of the bolt is restrained by the protective wall to prevent further slackening, and thus the detachment from the cylinder body is prevented.

The protective wall is installed at a fixed position at the same time when the protective wall is attached to the rear wheel braking hydraulic control device on the master cylinder.

(3) Embodiment One embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1, a negative pressure type booster 1 fixed to a dashboard (not shown) is installed in one corner of an automobile engine room Re, and a tandem type master cylinder 2 is installed on the front surface thereof.

The master cylinder 2 is provided with first and second connection bosses 3 ₁ and 3 ₂ arranged on the left side surface thereof in the front-rear direction, and the rear wheel braking hydraulic control device 6 is attached to these. The rear wheel braking hydraulic control device 6 has a third and a fourth connection bosses 3 ₃ , 3 arranged on the upper surface thereof in the front-rear direction.
₄ , 5th and 6th connection bosses 3 ₅ arranged in front and back on the left side,
3 includes a _6, third and fourth connecting boss 3 _3, 3 ₄ on the right and left front wheel brake Bfr, hydraulic conduits 5 ₁ contiguous respectively Bfl,
5 ₂ are respectively connected, also the fifth and sixth connecting boss 3 _5, 3
₆ left and right rear wheel brake Brl the hydraulic conduits 5 ₃ contiguous respectively to Brr, 5 ₄ are respectively connected.

As shown in FIGS. 2 and 4, in the cylinder hole 10a of the cylinder body 10 of the master cylinder 2, first and second hydraulic chambers 11 ₁ and 11 ₂ which are independent from each other are defined in the front and rear directions.
A pair of front and rear pistons 12 ₁ and 12 ₂ are slidably fitted.
These pistons 12 ₁ and 12 ₂ are biased in the backward direction by return springs 15 ₁ and 15 ₂ , respectively.

The retracting limit of the front piston 12 ₁ is restricted by supporting the piston 12 ₁ by the tip of a stop bolt 14 ₁ (see FIG. 5) screwed to the left side wall of the cylinder body 10. The retraction limit of the rear piston 12 _2, bearing 14 ₂ fixed to the rear end inner wall of the cylinder bore 10a is restricted by supporting the piston 12 _2. This rear piston 12 _2,
The output rod 1a of the booster 1 is connected to drive this.

Further, the on the left side surface of the cylinder body 10 which stop bolt 14 ₁ of the head is exposed, said first and second connecting bosses
3 ₁ and 3 ₂ are integrally projected, and the first connection boss 3 ₁ has a first output port 13 ₁ communicating with the first hydraulic chamber 11 ₁ and the second connection boss 3 _1.
3 ₂ The second output port 13 ₂ are respectively bored in communication with the second hydraulic chamber 11 _2.

Further, a cylindrical auxiliary oil reservoir 16 protruding from the upper surface of the cylinder body 10 is integrally formed at the front portion thereof. The auxiliary oil sump 16 is divided into first and second oil sump chambers 18 ₁ and 18 ₂ by a partition 17 that is integral with the cylinder body 10. The first oil reservoir chamber 18 ₁ is disposed near the front end portion of the front piston 12 _1, a relief port 19 ₁ and the supply port 20 ₁ for the first hydraulic chamber 11 ₁ is bored in the bottom wall thereof It

On the other hand, an oil passage 21 extending rearward from the second oil reservoir chamber 18 ₂ is formed on the upper wall of the cylinder body 10, and a relief port 19 ₂ for the second hydraulic chamber 11 ₂ is formed on the bottom wall of the oil passage 21. and supply port 20 ₂ is bored.

On the outer circumference of the auxiliary oil sump 16, a larger capacity than both oil sump chambers 18
A main oil sump 22 communicating with ₁ , 18 ₂ is fitted and connected. The main oil sump 22 is provided with a filter 23 for filtering hydraulic oil, and an oil level detection device 24 that operates when the level of the hydraulic oil storage level drops below a prescribed level L. This oil level detection device 24 is provided on a lower surface of a cap 25 of the main oil sump 22 and has a switch cylinder 26 that protrudes deeply into the main oil sump 22, and is housed in the switch cylinder 26 to have the specified level L position. The reed switch 27 and the annular float 29, which is fitted to the outer periphery of the switch cylinder 26 so as to be able to move up and down and has the magnet 28 embedded in the inner peripheral surface thereof. When the float 29 descends to the specified level L, Magnet 28
The reed switch 27 is adapted to be closed in response to the magnetism. The reed switch 27 is connected to an alarm device 30 such as a lamp that operates when the reed switch 27 is closed.

As shown in FIG. 3 and FIG. 4, the rear wheel braking hydraulic control device 6 includes a cylinder portion 32 parallel to the cylinder body 10.
And a housing 31 including a pair of front and rear ears 33 ₁ and 33 ₂ protruding from the lower surface of the cylinder portion 32.
The third and fourth connection bosses 3 ₃ and 3 ₄ are integrally formed on the upper surface of 2, and the fifth and sixth connection bosses 3 ₅ and 3 ₆ are integrally formed on the left side surface.

Both ears 33 _1, 33 _2, union bolt 3 that penetrates these
4,34 are oil-tightly fixed to the first and second connection bosses 3 ₁ , 3 ₂ , respectively.

On the seating surface of each ear portion 33 ₁ , 33 ₂ with respect to the head portion of the union bolt 34, a plurality of pin holes arranged at equal intervals along the periphery thereof.
55 is provided in one of these pin holes 55, and the detent pin 56 that abuts against the head side surface of the union bolt 34 is provided in any one of these pin holes 55.
Is driven. This prevents the union bolt 34 from loosening.

Each union bolt 34 has a corresponding first and second connection boss.
It has a T-shaped oil passage 35 and an annular groove 36 communicating with the output ports 13 ₁ and 13 ₂ of 3 ₁ and 3 ₂ , and the ear portions 33 ₁ and 33 ₂ have corresponding annular grooves 36 in the cylinder portion. First, which communicates with 32 cylinder holes 32a
The second inflow ports 37 ₁ and 37 ₂ are drilled, respectively.

The cylinder hole 32a of the cylinder part 32 is open at one end, and the open end is closed by a screw plug 38. The cylinder hole 32a has first and second pressure-receiving pistons 39 ₁ , 3 having the same diameter as each other.
9 ₂ is slidably fitted. Each pressure-receiving pistons 39 _1, 39 ₂ are small cylinder hole 40 ₁ of the same diameter, 40 ₂ formed with each other, these small cylinder hole 40 _1, 40 _2, the valve moves to mutually contact the back to each other The pistons 41 ₁ and 41 ₂ are slidably fitted together. Between the two pressure receiving piston 39 _1, 39 _2, via a spacer 42 _1, 42 _2, a common one pressure control spring 43 is mounted under compression. Each of the spacers 42 ₁ and 42 ₂ has a flange portion 42a that is sandwiched between the pressure receiving pistons 39 ₁ and 39 ₂ and the pressure adjusting spring 43 at its outer end, and faces the outer end surface of each flange portion 42a. Shoulders 41a are formed on the outer circumferences of the valve moving pistons 41 ₁ and 41 ₂ .

In both small cylinder holes 40 ₁ and 40 ₂ , the valve moving piston 4
1 _1, 41 by the outer end of the ₂ first and second input hydraulic pressure chamber 44 _1, 44 ₂
However, both pressure receiving pistons 3 are attached to both ends of the cylinder hole 32a.
9 _1, 39 ₂ outside the first and second output hydraulic chamber by end 45 _1, 45 ₂ are respectively defined, in the pressure-receiving pistons 39 _1, 39 each output hydraulic chamber 45 ₁ of _2, 45 ₂ side The pressure receiving area is the input hydraulic chamber 44 ₁ , 44 ₂
It is larger than the pressure receiving area on the side.

The end walls of the small cylinder holes 40 ₁ and 40 ₂ are provided with valve holes that connect the adjacent input and output hydraulic chambers 44 ₁ and 45 ₁ and 44 ₂ and 45 ₂ respectively.
47 ₁ and 47 ₂ are formed, and these valve holes 47 ₁ and 47 ₂ are valved.
The valve-opening rods 49 ₁ and 49 ₂ projecting from the outer ends of 48 ₁ and 48 ₂ can penetrate therethrough.

Valve springs 50 ₁ and 50 ₂ are compressed between the valves 48 ₁ and 48 ₂ and the valve moving pistons 41 ₁ and 41 ₂ , respectively, and normally the valve opening rods 49 _{1 of the} valves 48 ₁ and 48 ₂ are opened. , 49 _{2 contact} the end wall of the cylinder hole 32a and the inner end of the screw plug 38, respectively, and hold the valves 48 ₁ , 48 ₂ in the open position at the outer sliding limit of each pressure receiving piston 39 ₁ , 39 _2. It is supposed to do. And each pressure receiving piston 39 ₁ , 39
_{When 2} moves inward and the valves 48 ₁ and 48 ₂ are seated on the end walls of the small cylinder holes 40 ₁ and 40 ₂ , the valve holes 47 ₁ and 47 ₂ are closed.

Connectors 51 ₁ and 51 ₂ are integrally connected to the inner ends of the valves 48 ₁ and 48 ₂ , respectively. The inner ends of these connectors 51 ₁ , 51 ₂ are stoppers 52 provided on the outer ends of the pistons 41 ₁ , 41 ₂ when the valve moving pistons 41 ₁ , 41 ₂ move inward by a predetermined distance l _2. It is adapted to engage with ₁ , 52 ₂ . This distance l ₂ is larger than the distance l ₁ that the pressure receiving pistons 39 ₁ , 39 ₂ move from the valve opening position of the valves 48 ₁ , 48 _{2 to} the valve closing position, and this distance l ₁ and the valve moving pistons 41 ₁ , 41 ₂
Is set to be smaller than the sum of the distance l ₃ from the neutral position to the position where it comes into contact with the flange portion 42a of the spacers 42 ₁ and 42 ₂ . That is the _{l 1 <l 2 <l 1} + l 3.

A discharge hole 53 is provided in a side wall of an intermediate portion of the housing 31 which accommodates the pressure adjusting spring 43, and the discharge hole 53 is usually a rubber plug.
Blocked by 55. If the rubber plug 55, the pressure receiving pistons 39 ₁ and 39 ₂ and the seal members around the valve moving pistons 41 ₁ and 41 ₂ are damaged and the hydraulic oil leaks from the input hydraulic chambers 44 ₁ and 44 ₂ , the leaking operation is performed. The pressure of the oil ruptures or separates, and the rupture or separation causes the leaked hydraulic oil to flow out from the discharge hole 53, so that damage to the seal member is prevented from occurring in the main oil of the master cylinder 2. The oil pressure detecting device 24 can detect an abnormal decrease in the oil level in the reservoir 22.

The first and second input hydraulic chambers 44 ₁ and 44 ₂ have the first and second inflow ports 37 ₁ and 37 ₂ and the third and fourth connection bosses 3 ₃ and
3 ₄ The first and second outlet ports 46 drilled in _1, 46 ₂ and is communicated respectively. The first inflow port 37 ₁ and the first outflow port 46 ₁ and the second inflow port 37 ₂ and the second outflow port 46 ₂ are coaxially arranged so that they can be drilled by the same drilling tool. The first and second outflow ports 46 ₁ and 46 ₂ are connected to the third and fourth connection bosses 3 ₃ and 3 ₄ by the right and left front wheel brakes B.
The conduits 5 ₁ and 5 ₂ communicating with fr and Bfl are flare bolts 57 and
57 respectively connected.

The fifth and fifth output hydraulic chambers 45 ₁ and 45 ₂ have
And sixth connecting boss 3 _5, 3 ₆ the third and fourth outlet ports 46 ₃ are formed in, 46 ₄ lead. And the fifth and sixth connection bosses 3
_5, 3 _6, third and fourth outlet port 46 _3, 46 ₄ the left and right rear wheel brake Brl, conduit 5 _3, 5 ₄ for respectively communicating with Brr are connected by respective Fureyaboruto 58.

In FIGS. 3 and 5, the stop bolt of the master cylinder 2 is attached to the cylinder portion 32 of the housing 31.
Protection wall 59 covering the close to 14 ₁ of the head 62 are integrally formed.

Next, the operation of this embodiment will be described. When the master cylinder 2 is not operating, the first and second pressure receiving pistons 39 ₁ and 39 ₂ in the rear wheel braking hydraulic control device 6 are both pressure regulating springs 4.
It is pressed to the outer sliding limit shown in FIG. 3 by the set load of 3, and the valves 48 ₁ and 48 ₂ are opened, respectively, between the first and second input / output hydraulic chambers 44 ₁ and 45 ₁ and Both 44 ₂ and 45 ₂ are in communication with each other.

If you operate the booster 1 and drive the master cylinder 2 with its output rod 1a, both front and rear pistons 12
_The hydraulic pressure generated in the first and second hydraulic chambers 11 ₁ and 11 ₂ by the forward movement of ₁ and 12 ₂ is output from the first and second output ports 13 ₁ and 13 ₂ , and the first and second inflow ports 37 ₁ , 37 ₂ and is input to the first and second input hydraulic chambers 44 ₁ , 44 ₂ of the rear wheel braking hydraulic control device 6, respectively.

On the one hand, the hydraulic pressure input to the first and second input hydraulic chambers 44 ₁ and 44 ₂ passes through the input chambers 44 ₁ and 44 ₂ without passing, and the first and second outflow ports 46 ₁ and 46 ₂ and the hydraulic conduit 5 _1, 5 ₂ via a right, left front wheel brake Bfr, is transmitted to Bfl, to operate these.
On the other hand, the valve holes 47 ₁ and 47 ₂ and the first and second output hydraulic chambers 45 ₁ and 4
5 ₂ , 3rd and 4th outflow ports 46 ₃ and 46 ₄ and hydraulic conduits 5 ₃ and 5 ₄
To the left and right rear wheel brakes Brl and Brr.
Operate them.

Then, as the output hydraulic pressure of the master cylinder 2 rises,
The pressure in the first and second input / output hydraulic chambers 44 ₁ , 44 ₂ ; 45 ₁ , 45 ₂ also rises, but when the pressure reaches a certain value, the first and second pressure receiving pistons 39 ₁ , 39 ₂ The differential hydraulic pressure acting on each pressure receiving piston 39 ₁ , 39 ₂ becomes larger than the set load of the pressure adjusting spring 43 due to the difference in pressure receiving area between the inner and outer sides of the first and second pressure receiving pistons 39 ₁ , 39 ₂ . When the pressure adjusting springs 43 move inward while compressing each, and the moving distance reaches l ₁ , the valve
48 ₁ and 48 ₂ close the valve holes 47 ₁ and 47 ₂ . As a result, the output hydraulic chamber
The increase of the hydraulic pressure in 45 ₁ , 45 ₂ , that is, the braking hydraulic pressure of the rear wheel brakes Brl, Brr is stopped.

When the output hydraulic pressure of the master cylinder 2 further rises, the pressure in the input hydraulic chambers 44 ₁ and 44 ₂ rises, and the pressure receiving pistons 3
Push 9 ₁ and 39 ₂ outward. Therefore, the valves 48 ₁ , 48 ₂
Opens again and increases the pressure in the output hydraulic chambers 45 ₁ , 45 ₂ . When this pressure reaches a certain value, the first and second pressure receiving pistons 39 ₁ and 39 ₂ are actuated again, the valve holes 47 ₁ and 47 ₂ are closed, and the increase of the pressure is stopped. By repeating such an operation, the braking oil pressure of each rear wheel is the output oil pressure of the master cylinder 2 reduced at a constant ratio.

On the other hand, since the output hydraulic pressure of the master cylinder 2 directly passes through the input hydraulic chambers 44 ₁ and 44 ₂ and directly acts on the front wheel brakes Bfl and Bfr, the braking hydraulic pressure of the front wheels increases as the output hydraulic pressure of the master cylinder 2 increases. Increase rapidly. In this way, when braking strongly, the brakes Bfl and Bfr are strongly applied to the front wheels on the side where the vehicle body leans forward and the downward load increases.
For the rear wheel where the load decreases, the brake Brf,
Since Brr is actuated weakly, efficient braking can be performed.

Then, one of the strains of the braking hydraulic circuit, for example a hydraulic circuit of the second output port 13 ₂ side by failure, and the braking hydraulic pressure to the left front wheel brake Brl and the right rear wheel brake Brr no longer applied. If the booster 1 is operated at this time, only the output hydraulic pressure from the left and right first output ports 13 ₁ of the master cylinder 2 becomes effective.

Thus, according to the output hydraulic pressure from the first output port 13 ₁ , the pressure in the first input hydraulic chamber 44 ₁ rises, but the pressure in the second input hydraulic chamber 44 ₂ does not rise. Therefore, the valve moving pistons 41 ₁ and 41 ₂ are both rearward (to the right in FIG. 3).
To move the front valve moving piston 41 ₁ to the spacer 42 ₁
Abutting on the flange portion 42a of. Then, the valve moving piston 41 ₁ compresses the pressure adjusting spring 43 via the spacer 42 ₁ as the valve moving piston 41 ₁ moves.

As a result, the pressing force is not applied by the pressure control spring 43 to the first pressure receiving piston 39 _1, the pressure receiving piston 39 ₁
Are moved inward or backward by the differential pressure from the inside and outside.

When the valve moving piston 41 ₁ moves rearward by a predetermined distance l ₂ , the stopper 52 ₁ at its outer end engages with the inner end of the connector 51 ₁ and moves the valve 48 ₁ inward. Distance l ₂ is l ₁
Since it is set to be smaller than + l ₃ , the valve 48 ₁ is separated from the end wall of the small cylinder hole 40 ₁ during this period, and the valve open state is maintained.

Thus, in the valve moving piston 41 ₁ , the valve 48 ₁ , and the first pressure receiving piston 39 ₁ , the inner end of the spacer 42 ₁ is the other spacer.
To a position abutting the inner end of the 42 _2, it moves inward.

In the state where the valve moving piston 41 ₁ moves most inward and the inner ends of the spacers 42 ₁ and 42 ₂ are in contact with each other, the first
The inner end of the pressure receiving piston 39 ₁ also has a flange portion of the spacer 42 ₁ .
Although it has moved to a position where it abuts against 42a, at this time, since the stopper 52 ₁ is engaged with the inner end of the connector 51 ₁ , the valve 48 ₁ continues to open the valve hole 47 ₁ . Therefore, the output hydraulic pressure from the first output port 13 ₁ of the master cylinder 2 is directly transmitted to the first output hydraulic pressure chamber 45 ₁ , and the first output port 13 ₁
The rear wheels of this system will be braked with the same strength as the front wheels. That is, when one of the systems fails, the rear wheel braking hydraulic control device 6 operates without reducing the braking hydraulic pressure of the rear wheels. Therefore, the rear wheel braking hydraulic control device 6 has a bypass function. It has been granted.

If the master cylinder 2 is returned to the inoperative state to release the braking, the input hydraulic chambers 44 ₁ and 44 ₂ are decompressed accordingly,
The operation of the front wheel brakes Bfr, Bfr is immediately released.

On the other hand, when the pressure receiving pistons 39 ₁ and 39 ₂ are in the inward moving position and the valves 48 ₁ and 48 ₂ are closed at this time, the hydraulic pressure of the output hydraulic chambers 45 ₁ and 45 ₂ is the input hydraulic chamber 44 ₁ , 44 ₂ is relatively higher than the oil pressure of 44, 45 ₂ , but due to the pressure difference between the input and output hydraulic chambers 44 ₁ , 45 ₁ and 44 ₂ , 45 _{2, the} valves 48 ₁ , 48 ₂ are opened. The valve holes 47 ₁ and 47 ₂ are opened. As a result, the output hydraulic chamber 4
The pressure of 5 ₁ , 45 ₂ can also be reduced to release the operation of the rear wheel brakes Brl, Brr.

In such a two-system hydraulic braking device, the head 62 of the stop bolt 14 ₁ that restricts the retreat limit of the front piston 12 ₁ of the master cylinder 2 is covered by the protective wall 59 close to it, so that the engine when engine maintenance or the like in the room Re, tool or the like is also close to the stop bolt 14 ₁ can be prevented by the protection wall 59 to collide with the bolt 14 _1. Moreover also stop bolt 14 ₁ Should loosened due to vibration or the like, looseness over a certain amount of the bolt 14 ₁ by the protection wall 59, thus it is possible to prevent separation from the cylinder body 10.

Moreover, since the protection wall 59 is formed integrally with the housing 31 of the rear wheel braking hydraulic pressure control device 6, it is installed at a fixed position at the same time when the rear wheel braking hydraulic pressure control device 6 is mounted on the master cylinder 2. The mounting member dedicated to the protective wall 59 is unnecessary.

On the other hand, the first and second connection bosses 3 ₁ , 3 of the master cylinder 2
₂ , the union bolts 34, 34 for fixing the ears 33 ₁ , 33 ₂ of the rear wheel braking hydraulic control device 6, and the rear wheel braking hydraulic control device 6
The flare bolts 57 and 57 for connecting the left and right front wheel brake hydraulic conduits 5 ₁ and 5 ₂ to the third and fourth connection bosses 3 ₃ and 4 ₄ are to be installed separately from each other. The specified tightening torque can be easily applied to the bolts 34 and 57 individually.

The left and right front wheel brakes Bfl, Bfr are connected to the first and second inputs of the rear wheel braking hydraulic control device 6 through the first and second outflow ports 46 ₁ , 46 _{2 of} the third and fourth connection bosses 3 ₃ , 3 ₄ . Hydraulic chamber 44 ₁ ,
Because adapted to receive a 44 _second hydraulic, the formation of the third and fourth connecting boss 3 _3, 3 ₄ of the housing 31,
It is possible to freely select the forming position from a wide range around the first and second input hydraulic chambers 44 ₁ and 44 ₂ , and it is convenient that various piping forms of the hydraulic conduits 5 ₁ and 5 ₂ can be taken. .

C. Effect of the Invention As described above, according to the present invention, the protection is provided in the vicinity of the head of the stop bolt screwed to the side wall of the cylinder body to cover the front piston of the master cylinder in order to restrict the backward movement of the piston. Since the wall is formed integrally with the housing of the rear wheel braking hydraulic control device, it is possible to prevent the collision of the foreign matter with the stop bolt and the slackening and separation of the stop bolt by a certain amount or more. Moreover, since the protective wall is installed at a fixed position at the same time as the mounting of the rear wheel braking hydraulic control device to the master cylinder, a mounting member dedicated to the protective wall is not required and the structure is extremely simple.

[Brief description of drawings]

The drawings show an embodiment of the present invention. FIG. 1 is a plan view of a two-system hydraulic braking system for automobiles, and FIGS. 2, 3, and 4 are II-II lines of FIG. , III-III line and IV-IV line enlarged sectional view, FIG. 5 is a VV line sectional view of FIG. Bfl …… left front wheel brake, Bfr …… right front wheel brake, Brl
...... Left rear wheel brake, Brr …… Right rear wheel brake, 1 ……
Booster, 2 ... Master cylinder, 3 _{1 to} 3 ₆ ... 1st to 6th connection boss, 5 _{1 to} 5 ₄ ... Hydraulic conduit, 6 ... Rear wheel braking hydraulic control device, 10 ... Cylinder body, 11 ₁ , 11 ₂ …… First and second
Hydraulic chamber, 13 ₁ , 13 ₂ ...... First and second output ports, 14 ₁ ...... Stop bolt, 31 ...... Housing, 33 ₁ , 33 ₂ ...... Ear, 34
…… Union bolt, 37 ₁ , 37 ₂ …… First and second inflow ports, 44 ₁ , 44 ₂ …… First and second input hydraulic chambers, 45 ₁ , 45 ₂ …… First 1,
Second output hydraulic chamber, 46 _{1 to} 46 ₄ ... 1st to 4th outflow port,
57,58 …… Flare bolt, 59 …… Protection wall, 62 …… Head

Claims (1)

[Scope of utility model registration request] 1. A cylinder body (1) of a master cylinder (2).
0) inside the first and second hydraulic chambers (11 ₁ , 11 ₂ ) independent of each other
Accommodating a pair of front and rear pistons (12 ₁ , 12 ₂ ) that define
Further, the first and second parts are provided on one side surface of the cylinder body (10).
First and second output ports (13 ₁ , 1) of the hydraulic chamber (11 ₁ , 11 ₂ ).
3 first and second connecting bosses having ₂₎ (3 _1, 3 ₂₎ projecting, and these connection bosses (3 _1, 3 _2), the left and right rear wheel brake by controlling the input pressure (Brl. A pair of ears (33 ₁ , 33 ₂ ) projecting from one side of the housing (31) of the rear wheel braking hydraulic control device (6) for outputting to Brr) are fixed by union bolts (34), respectively. Part (33 ₁ , 33 ₂ ) has the first
And the output hydraulic pressure from the second output port (13 ₁ , 13 ₂ ) to the first and second input hydraulic chambers (44) of the rear wheel braking hydraulic pressure control device (6).
_1, 44 ₂₎ first and second inlet port for introducing the (37 _1, 37 ₂₎
In a two-system hydraulic braking device for an automobile, each of which is provided with a stop bolt (which is screwed to the side wall of the cylinder body (10) to restrict the retreat limit of the front piston (12 ₁ ) of the master cylinder (2). 14 ₁ ) close to the head (62) of the head (6
The rear wall braking hydraulic control device (6) is provided with a protective wall (59) that covers the 2).
A two-system hydraulic braking system for an automobile, characterized in that it is formed integrally with the housing (31).