JP3526712B2 - Load response type brake hydraulic control valve - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a load responsive brake hydraulic pressure control valve used for controlling brake hydraulic pressure of automobiles, motorcycles and the like, and more particularly to a casing, and an input chamber communicating with an output port of a master cylinder. A valve piston that forms an output chamber that communicates with the wheel brakes and controls opening and closing between the two chambers so that the hydraulic pressure in the input chamber is proportionally reduced and transmitted to the output chamber, and the depressurizing action starting point of this valve piston The pressure regulating spring that biases the pressure regulating spring in a fixed direction and the nut plate that supports the pressure regulating spring on the side opposite to the valve piston are housed, and the load detection shaft that is screwed into this nut plate is rotated on the casing. It is freely and axially immovably supported, and the load detection shaft is rotated forward and backward in order to move the nut plate forward and backward relative to the pressure adjusting spring according to the increase or decrease of the vehicle load. About.

[0002]

2. Description of the Related Art Such a load responsive brake hydraulic control valve is already known, as disclosed, for example, in Japanese Utility Model Publication No. 31578/1989.

[0003]

Conventionally, in such a load responsive brake hydraulic control valve, it has not been considered to adjust the set load of the pressure regulating spring to a constant value. After that, the starting point of the depressurizing action of the valve piston with respect to the loaded weight often varies.

The present invention has been made in view of the above circumstances, and the load responsive brake hydraulic pressure is such that the set load of the pressure adjusting spring can be easily and surely adjusted before mounting on the vehicle. The purpose is to provide a control valve.

[0005]

In order to achieve the above object, the present invention provides a casing with an input chamber communicating with an output port of a master cylinder and an output chamber communicating with a wheel brake. The valve piston that controls the opening and closing between the two chambers so that the hydraulic pressure in the chamber is proportionally reduced and transmitted to the output chamber, and the pressure adjustment that biases this in a certain direction to determine the decompression action start point of this valve piston. A spring and a nut plate that supports a pressure adjusting spring on the side opposite to the valve piston are housed, and a load detection shaft that is screwed into this nut plate is supported by the casing so that it can rotate but cannot move in the axial direction. In the load-responsive brake hydraulic control valve, the nut plate can be rotated in the casing in the load response type brake hydraulic control valve in which the load detection shaft is rotated forward and backward to move the nut plate forward and backward with respect to the pressure adjustment spring according to the increase and decrease of weight. A cylindrical fixing chamber is formed therein, and an adjusting fixing plate that is axially displaceably connected to the nut plate through a connecting means is rotatably fitted to the cylindrical chamber, while the casing is loaded at a predetermined position. The first feature is that provisional fixing means for temporarily fixing the detection shaft and fixing means for fixing the adjustment fixing plate at an arbitrary rotational position are provided.

When the load-responsive brake hydraulic control valve is assembled, the set load of the pressure-adjusting spring is fixed by rotating the nut plate while the load detecting shaft is fixed to the casing at the predetermined position by the temporary fixing means. It can be adjusted precisely. Further, after the adjustment, the adjustment fixing plate is fixed to the casing by the fixing means, so that the rotation of the nut plate can be prevented and the axial displacement thereof can be allowed. Then, if the temporary fixing means is removed when the brake hydraulic pressure control valve is mounted on the vehicle, an appropriate load corresponding to the loaded weight of the vehicle can be applied to the pressure adjusting spring.

According to the present invention, in addition to the above features, the connecting means is provided with a connecting pin which is erected on one of the nut plate and the adjusting and fixing plate and extends parallel to the load detecting shaft, and is provided on the other of the connecting pins. A second feature is that the connecting pin is configured with a pin hole into which the connecting pin is slidably fitted.

Thus, when the adjusting and fixing plate is fixed, the rotation of the nut plate can be prevented through the connecting pin, and its axial displacement can be allowed.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The embodiments of the present invention will be described below based on the embodiments of the present invention shown in the accompanying drawings.

First, the first aspect of the present invention shown in FIGS.
Examples will be described. Fig. 2 shows the brake system of an automobile
Indicates. In the figure, M is a brake pedal 1.
It is a tandem type master cylinder that is driven by its first output port.
Red P₁To the first oil passage L₁Left front wheel brake through Bfl
Of the wheel cylinder of the second output port P₂To
Second oil passage L₂Right front wheel brake through Bfr wheel
Each cylinder is connected. First oil passage L₁And the second
Oil passage L₂Third oil passage L branched from₃And the fourth oil
Road L_FourAre piped crossing each other left and right, and the third oil passage
L₃The wheel cylinder of the right rear wheel brake Brr is
4th oil passage L_FourLeft rear wheel brake Brl wheel series
Are connected to each other. And the third oil passage L₃And the
4 oil passage L _FourThe load of the present invention to intervene during each of the
A responsive brake hydraulic control valve V is provided.

The casing 3 of the brake hydraulic control valve V
Are opposite flanges 3₁a, 3 ₂each has a
First and second casing halves 3₁, 3₂It consists of
And their flange 3₁a, 3₂a is a plurality of bolts 2
Joined by 0. At that time, the first casing half 3₁
The circular positioning recess 21 formed on the joint end surface of
2 casing half 3₂Circular position formed on the joint end face of
The locating tubular portion 22 is fitted via the seal member 24.

The first casing 3 is provided with a first pressure reducing valve 2 ₁ and a second pressure reducing valve 2 ₂ which respectively intervene in the third oil passage L ₃ and the fourth oil passage L ₄ , and the second casing half body. 3 ₂
A pressure adjusting spring 25 that determines the pressure reducing action starting point of the pressure reducing valves 2 ₁ , 2 ₂ is provided in the.

Since the structures of the first and second pressure reducing valves 2 ₁ and 2 ₂ are the same, only the structure of the first pressure reducing valve 2 ₁ will be described with reference to FIG.

The first casing half 3 ₁ is provided with inlet / outlet ports 4 and 5 and inlet / outlet chambers 6 and 7 connected to these inlet / outlet ports 4 and 5, respectively. 3 upstream of the oil passage L ₃ (in the second pressure reducing valve 2 ₂ , the fourth
The upstream side of the oil passage L ₄ ) is connected, and the downstream side of the oil passage L ₃ (the downstream side of the fourth oil passage L ₄ in the second pressure reducing valve 2 ₂ ) is connected to the outlet port 5.

Each of the input and output chambers 6 and 7 has a cylindrical shape. The output chamber 7 is formed to have a smaller diameter than the input chamber 6, and one end of the input chamber 6 is provided with an annular step portion 8 therebetween. It is arranged so as to be coaxial.

The first casing half 3 ₁ is further provided with a large-diameter mounting hole 26 that opens to the bottom surface of the positioning recess 21 while the input chamber 6 is also connected to the outer end via an annular step. The guide member 9 is fitted thereinto via the seal member 23.

A valve seat member 11 formed of an elastic material such as rubber is mounted in the input chamber 6 so as to abut the annular step portion 8. This valve seat member 11 is provided with a valve hole 12 that is smaller in diameter than the output chamber 7 and that communicates between the output chambers 6 and 7 in the center thereof, and has an annular array on the end face facing the input chamber 6. A plurality of protrusions 13 are formed. Further, on the outer periphery of the valve seat member 11, a one-way seal lip 14 is formed which extends in the direction opposite to the annular step portion 8 and is in close contact with the inner peripheral surface of the input chamber 6.

Enter in cooperation with the valve seat member 11,
A valve piston 15 that connects and disconnects the output chambers 6 and 8 is inserted, and is arranged over the output chambers 6 and 7. That is, the valve piston 15 includes a valve rod 16 and a neck portion 1 having a small diameter at one end thereof.
7 and a piston-like valve portion 18 that is integrally connected via a valve body 7. The neck 17 is loosely penetrated into the valve hole 12 of the valve seat member 11, and the valve rod 16 is arranged in the input chamber 6. The guide member 9 is slidably supported by the guide member 9 via the seal member 10, and the valve portion 18 is disposed in the output chamber 7. The valve hole 12 can be opened / closed by separating / seating the valve portion 18 from / on the valve seat member 11. The valve portion 18 is provided with a through hole 19 that communicates between the front and rear end surfaces thereof.

In this way, the first and second pressure reducing valves 2 ₁ ,
2 ₂ are configured, and the guide members 9, 9 have a common holding plate 27 held by the positioning tubular portion 22 in the positioning recess 21 and the first casing half 3
The detachment from the mounting holes 26, 26 of ₁ is prevented.

Each valve rod 1 of the first and second pressure reducing valves 2 ₁ and 2 ₂
6 extends the end to the second casing half 3 in ₂ through the guide member 9 and the press plate 27. This second
Casing half 3 ₂ is a cylindrical chamber 28 having a bottom, in the center of the bottom wall, the load detecting shaft 29 therethrough is rotatably supported through a bush 30 and the seal member 31 It The load detection shaft 29 has a portion projecting into the cylindrical chamber 28 as an adjusting screw portion 29a, and a flange 29b that abuts the bottom surface of the cylindrical chamber 28 is formed at the base end thereof.

In the cylindrical chamber 28, an adjusting and fixing plate 32, which is in contact with the bottom surface thereof and is rotatably fitted to the inner peripheral surface thereof,
A nut plate 33 screwed into the adjusting screw portion 29a, a pressing plate 34 slidably fitted into the inner surface of the cylindrical chamber 28 while contacting the ends of the valve rods 16 of the pressure reducing valves 2 ₁ , 2 ₂ . The pressing plate 34 is inserted between the nut plate 33 and the pressing plate 34 so that the valve plate 1
A plurality of (two in the illustrated example) pressure regulating springs 25 that urge toward 6 are housed. The adjustment fixing plate 32 has a connecting pin 50.
Is erected parallel to the load detecting shaft 29, and the connecting pin 50 is slidably fitted in the pin hole 51 of the nut plate 33 to allow axial displacement of the nut plate 33. A connecting means 35 for connecting the fixed plate 32 and the nut plate 33 to each other in the rotational direction is configured.

A retainer 36 is interposed between the nut plate 33 and each pressure adjusting spring 25. The retainer 36 has a cylindrical portion 36 a arranged in the corresponding pressure adjusting spring 25, and an auxiliary spring 52 that biases the retainer 36 toward the pressure adjusting spring 25 is housed inside the tubular portion 36 a. The set load and spring constant of the auxiliary spring 52 are set to be much smaller than that of the pressure adjusting spring 25.

A lever 37 is fixed by a nut 38 to the outer end portion of the load detecting shaft 29 protruding outside the cylindrical chamber 28. Through the lever 37, the load detecting shaft 29 is temporarily operated from the time of assembling the brake hydraulic pressure control valve V to the time of mounting it on the vehicle.
A temporary fixing means 39 is provided for fixing the casing 3 to the casing 3 at a predetermined position. The temporary fixing means 39, locking hole 40 bored in the predetermined positions of the second casing half 3 ₂ of the bottom wall
And a temporary fixing screw 41 that penetrates the lever 37 and is screwed into the fixing hole 40.

_On the peripheral wall of the second casing half 32, a portion adjacent to a part of the peripheral surface of the adjusting and fixing plate 32 is provided with a thin wall 42a.
Therefore, the concave portion 42 is formed, and the adjustment fixing plate 32 is fixed to the casing 3 by caulking 43 the thin wall 42 a thereof with respect to the adjustment fixing plate 32. This constitutes the fixing means 44 of the adjusting and fixing plate 32.

[0025] The second peripheral wall of the casing half 3 ₂ is formed with a pair of mounting bosses 45, by using these, as shown in FIG. 1, the brake hydraulic pressure control valve V is an automobile frame 46 Mounted on. Then, the lever 37 is provided with a suspension arm 48 for the rear wheel Wr via a link 47.
Is linked and linked to.

When the load detection shaft 29 rotates in the direction of arrow 49 through the link 47 and the lever 37 as the suspension arm 48 swings upward due to an increase in the weight of the vehicle, the adjusting screw is moved. The portion 29a pushes the nut plate 33 into the pressing plate 3
4 is increased to increase the load of the pressure adjusting spring 25, and conversely, when the load detecting shaft 29 rotates in the direction opposite to the arrow 49 with the downward swing of the suspension arm 48, the adjusting screw portion thereof is formed. 29a retracts the nut plate 33 to the side opposite to the pressing plate 34 to reduce the set load of the pressure adjusting spring 25.

Next, the operation of this embodiment will be described.

In assembling the brake hydraulic pressure control valve V, first, the first and second pressure reducing valves 2 are attached to the first casing half 3 ₁ .
₁ and 2 ₂ and the holding plate 27 are attached.

On the other hand, the second casing half 3 ₂ has the structure shown in FIG.
The load detecting shaft 29 is mounted as shown in FIG. 2 and the lever 37 is attached to the load detecting shaft 29, and the lever 37 is fixed to a fixed position of the casing 3 by a temporary fixing screw 41. Then, the adjustment fixing plate 32 having the connecting pin 50 is fitted to the bottom of the cylindrical chamber 28 of the second casing 3, and the nut plate 33 is screwed onto the threaded portion 29a of the load detecting shaft 29 while the nut plate 33 is removed from the nut plate 33. 2 Adjusting the distance to the upper end surface of the casing 3 to a predetermined value d, and caulking the thin wall 42a of the recess 42 to caulk 43 the adjustment fixing plate 32 to keep the state.
Fixed to. At this time, the nut plate 33 and the adjustment fixing plate 3
2. Between the nut plate 33 and the flange 29b of the load detecting shaft 29, a sufficient space is secured to allow the load detecting shaft 29 to rotate in the direction opposite to the arrow 49. After that, the auxiliary spring 52, the retainer 36, and the pressure adjusting spring 25, which have been appropriately dimensioned, are placed on the nut plate 33, and the pressing plate 34 is fitted into the cylindrical chamber 28, and then the first and second casings 3 ₁ , 3 ₂ are bolted together. Thus, the set load of the pressure adjusting spring 25 is set to a predetermined value corresponding to the standard load weight of the vehicle, and the pressure reducing action starting points A (see FIG. 5) of the pressure reducing valves 2 ₁ , 2 ₂ are accurately determined.

According to the caulking 43 of the thin wall 42a,
The adjustment fixing plate 32 can be reliably fixed while ensuring the airtightness of the cylindrical chamber 28.

Brake oil pressure control valve V thus constructed
In (1), the lever 37 is fixed at a fixed position of the casing 3 by the temporary fixing screw 41 until it is mounted on the automobile. Therefore, it is possible to prevent the set load of the pressure regulating spring 25 from being deviated due to the blind motion of the load detection shaft 29 during the handling such as transportation.

Finally, the brake hydraulic control valve V is mounted on the frame 46 of the automobile, the temporary fixing screw 41 is removed, the lever 37 is connected, and the link 47 is connected to the suspension arm 48 of the rear wheel Wr.
To connect. When the suspension arm 48 swings upward due to an increase in the weight of the vehicle, the load detecting shaft 29 rotates in the direction of arrow 49 to move the nut plate 33 forward to the pressing plate 34 side. The load of the spring 25 can be increased, and conversely, when the suspension arm 48 swings downward due to the reduction of the vehicle load, the load detection shaft 29 rotates in the direction opposite to the arrow 49 and the nut plate. Since 33 is retracted to the side opposite to the pressing plate 34, the set load of the pressure adjusting spring 25 can be reduced.

When the master cylinder M is operated by depressing the brake pedal 1, the output hydraulic pressure from the first output port P ₁ is directly supplied to the left front wheel brake Bfl via the first oil passage L ₁ and the third hydraulic pressure is applied. It is supplied to the right rear wheel brake Brr via the oil passage L ₃ , that is, via the first pressure reducing valve 2 ₁ . Further, the output oil pressure from the second output port P ₂ is directly supplied to the right front wheel brake Bfr via the second oil passage L ₂ and also via the fourth oil passage L ₄ , that is, via the second pressure reducing valve 2 _2. It is supplied to the left rear wheel brake Brl.

Here, the first and second pressure reducing valves 2 ₁ and 2 ₂ operate as follows. At the beginning of the operation of the master cylinder M, the first and second pressure reducing valves 2 ₁ , 2 ₂ are in the open state, so that the first and second output ports P ₁ , P _{2 are connected} to the first and second pressure reducing valves 2 ₁ , 2. The hydraulic pressure supplied to each of the 2 ₂ input chambers 6 is directly transmitted to each of the output chambers 7 through each of the valve holes 12. When the oil pressure in the input chamber 6 increases to a predetermined value, the valve piston 15
3, the downward valve closing force (valve rod 16
Of the diameter D ₁ supported by the guide member 9 and multiplied by the hydraulic pressure of the output chambers 6 and 7).
The valve piston 15 is moved in the valve closing direction by overcoming the set load of 5, and the valve portion 18 is seated on the valve seat member 11 to close the valve hole 12, thereby shutting off the inlet and output chambers 6, 7.

The valve portion 18 and the valve seat member 11 are
Effective seal diameter is D₂Then, the effective system
Diameter D₂The hydraulic pressure of the output chamber 7 is multiplied by the area of the circle whose diameter is
The applied pressing force becomes the valve closing force of the valve piston 15, and
Diameter D₁And D₂(D₁<D₂) Input area 6
The pressing force multiplied by the oil pressure is the valve opening force of the valve piston 15.
Become. Therefore, after that, the oil pressure in the input chamber 6 further increases.
Then, the valve opening force due to the hydraulic pressure in the input chamber 6 is changed to the hydraulic pressure in the output chamber 7.
Valve closing direction by overcoming the valve closing force
Back to separate the valve portion 18 from the valve seat member 11.
Then, the two chambers 6 and 7 are electrically connected again. As a result, input
The increased hydraulic pressure in chamber 6 is supplied to output chamber 7,
When the valve closing force exceeds the valve opening force, the valve piston 15
Close the valve and shut off between both chambers 6 and 7. After that, the same operation
By repeating at high speed, the first and second pressure reducing valves 2₁，
Two₂Is the first and second ports P of the master cylinder M.₁，
P ₂The output hydraulic pressure of the
It can be supplied to Brr and Brl. Moreover, the above
As described above, the load of the pressure regulating spring 25 increases or decreases the loaded weight of the vehicle.
The left and right rear wheel brakes Br are adjusted to increase or decrease according to
As shown in FIG. 5, the decompression starting points of r and Brl are from A
It changes to B and C, and the left and right rear wheel brakes Brr and Brl
Can be operated efficiently.

By the way, in order to make the brake hydraulic pressure control valve V compact, the swing of the suspension arm 48 is greatly reduced and transmitted to the nut plate 33.
The spring constant of the spring 25 is set to be relatively large in order to change the load of the pressure regulating spring 25 as desired in accordance with the relatively small displacement of 3. Therefore, when the vehicle is traveling on a rough road, the suspension arm 48 may be violently bounced by the left and right rear wheels.
Is greatly oscillated downward, the opposite arrow 4 of the load detection shaft 29
The nut plate 33 may be largely retracted by the rotation in the 9 directions, and the nut plate 33 and the pressure adjusting spring 25 may be separated from each other. In such a case, the set load and the spring constant of the spring constant should be set so as to fill the gap. The smaller auxiliary spring 52 can be extended to apply the minimum necessary load to the pressure adjusting spring 25. Therefore, even during braking in that state, as shown in FIG.
Since the rear wheel brake hydraulic pressure is not reduced until the predetermined minimum depressurizing action starting point D is reached, the left and right rear wheel brakes Br are
It is possible to secure good responsiveness of l and Brr.

Next, when the depression force on the brake pedal 1 is released to return the master cylinder M to the inoperative state, the left and right front wheel brakes Bfl and Bfr are immediately released from the braking hydraulic pressure. On the other hand, in each of the pressure reducing valves 2 ₁ and 2 ₂ , the one-way seal lip 14 of the valve seat member 11 is radially inward due to the pressure difference between the input and output chambers 6 and 7 caused by the decrease in the hydraulic pressure of the input chamber 6. Since it bends to form a gap with the inner peripheral surface of the input chamber 6, hydraulic pressure moves from the output chamber 7 side to the input chamber 6 through the gap. As a result, when the output chamber 7 approaches the pressure of the input chamber 6, the valve piston 15 opens with the elastic force of the pressure adjusting spring 25. Thus, the left and right rear wheel brakes B
rl and Brr are also released from the braking hydraulic pressure.

The oil passage of one of the first output port P _{1 and} the second output port P ₂ of the master cylinder M, for example, the fourth
Assuming that a failure has occurred in the oil passage L ₄ , hydraulic pressure is generated only in the first and third oil passages L ₁ and L ₃ during braking in this case, and only the first pressure reducing valve 2 ₁ operates. since it becomes, more joined to one of the valve piston 15 (2 in the illustrated example four) of pressure control spring 25 set load all the first pressure reducing valve 2 _1, the first pressure reducing valve 2 ₁ of vacuum action starting point Will be much later than normal. Therefore, the pressure reduction of the hydraulic pressure of the right rear wheel brake Brr, which operates normally, can be suppressed as much as possible, and the shortage of the braking force due to the above failure can be compensated.

6 and 7 show a second embodiment of the present invention. The casing 3 of the load responsive brake hydraulic control valve V is equipped with the first and second pressure reducing valves 2 ₁ and 2 ₂ and has a casing body 3 a having a cylindrical chamber 28 whose lower surface is open, and the cylindrical chamber 28. A lid 3b joined by a bolt 53 to the casing body 3a to close the open surface.
And a load detecting shaft 29 at the center of the lid 3b.
Is installed. A thin annular wall 54 is integrally projectingly provided on the lower surface of the adjusting and fixing plate 32 that is rotatably fitted in the cylindrical chamber 28, and a circular pedestal 55 that is relatively rotatably fitted is fitted to the inner periphery of the annular wall 54. It is integrally formed on the upper surface of the body 3b. By crimping the annular wall 54 to the pedestal 55,
The adjustment fixing plate 32 is fixed. In addition, the first and second pressure reducing valve 2 _1, 2 _2, the guide member 9 is secured by a clip 56 to the casing body 3a.
Since other configurations are the same as those in the previous embodiment, in the figure, portions corresponding to those in the previous embodiment are designated by the same reference numerals, and description thereof will be omitted.

When the brake hydraulic control valve V is assembled, the load detecting shaft 29 is temporarily fixed to the means 3 as shown in FIG.
In the state of being fixed to a predetermined position of the lid body 3b by 9, the distance h between the lid body 3a and the load detecting shaft 29 is adjusted to a predetermined value while rotating the nut plate 33, and then the adjustment fixing plate is made by the caulking 43 described above. 32 is fixed, so that when the brake hydraulic control valve V is completely assembled, a set load corresponding to the standard load weight of the vehicle can be accurately applied to the pressure adjusting spring 25 when the brake hydraulic control valve V is completely assembled. it can.

The present invention is not limited to the above embodiments, and various design changes can be made without departing from the scope of the invention. For example, the load responsive brake hydraulic pressure control valve V may be individually configured for each of the first and second pressure reducing valves 2 ₁ , 2 ₂ .

[0042]

As described above, according to the first aspect of the present invention, the casing is provided with the cylindrical chamber for rotatably accommodating the nut plate, and the nut plate is connected to the nut plate through the connecting means. The adjustment fixing plate, which is connected so that it can be displaced in the axial direction, is rotatably fitted, while the temporary fixing means for temporarily fixing the load detection shaft to the casing at the predetermined position and the adjustment fixing plate are set at arbitrary rotation positions. When the load response type brake hydraulic control valve is assembled, the nut plate is rotated to fix the pressure adjusting spring while the load detecting shaft is fixed to the casing at the predetermined position by the temporary fixing means. Precisely adjust the set load of the pressure adjusting spring, and after adjusting, fix the adjusting fixing plate to the casing by the fixing means to ensure that the pressure adjusting spring has the proper set load until the brake hydraulic control valve is mounted on the vehicle. After mounting on the vehicle, it is possible to apply an appropriate load to the pressure regulating spring corresponding to the loaded weight of the vehicle, and thus contribute to stabilizing the braking characteristics of vehicles of the same vehicle type. You can

According to the second aspect of the present invention, the connecting means is provided with a connecting pin which is erected on one of the nut plate and the adjusting and fixing plate and extends parallel to the load detecting shaft, and is provided on the other of them. Since this connecting pin is configured with the pin hole into which it can be slidably fitted, the rotation of the nut plate can be prevented and the axial displacement thereof can be allowed with a simple structure.

[Brief description of drawings]

FIG. 1 is a rear view of a main part of an automobile equipped with a load-responsive brake hydraulic control valve according to a first embodiment of the present invention.

FIG. 2 is a brake hydraulic circuit diagram of an automobile equipped with the brake hydraulic control valve.

FIG. 3 is an enlarged sectional view of an essential part of the brake hydraulic pressure control valve.

FIG. 4 is an explanatory diagram when adjusting a set load of a pressure adjusting spring in the brake hydraulic pressure control valve.

FIG. 5 is a characteristic diagram of the brake hydraulic pressure control valve.

FIG. 6 is a brake hydraulic circuit diagram similar to FIG. 2, showing a second embodiment of the present invention.

FIG. 7 is an explanatory view when adjusting the set load of the pressure adjusting spring in the brake hydraulic pressure control valve.

[Explanation of symbols]

Brl ··· wheel brake (left rear wheel brake) Brr ··· wheel brake (right rear wheel brake) P ₁ ···· output port (first output port) P ₂ ···· output port (the second output Port) M ... Master cylinder V ... Load response type brake hydraulic control valve 3 ... Casing 6 ... Input chamber 7 ... Output chamber 15 ...・ Valve piston 25 ・ ・ ・ ・ Pressure adjusting spring 28 ・ ・ ・ ・ ・ ・ Cylinder chamber 29 ・ ・ ・ ・ Load detection shaft 32 ・ ・ ・ ・ Adjustment fixing plate 33 ・ ・ ・ ・ ・ ・ Nut plate 35 ・ ・ ・ ・ ・ ・ Connecting means 39 ・... Temporary fixing means 44 ...

Claims (2)

(57) [Claims] 1. A casing (3) having an input chamber (6) communicating with output ports (P ₁ , P ₂ ) of a master cylinder (M) and an output chamber (7) communicating with wheel brakes (Brl, Brr). ), And a valve piston (15) for controlling opening / closing between both chambers (6, 7) so that the hydraulic pressure in the input chamber (6) is proportionally reduced and transmitted to the output chamber (7).
And a pressure adjusting spring (25) for urging the valve piston (15) in a certain direction so as to determine the starting point of the pressure reducing action of the valve piston (15).
On the side opposite to the valve piston (15)
5) and a nut plate (33) for supporting the load plate, and a load detection shaft (29) screwed to the nut plate (33) is rotatably and axially immovably supported by the casing (3). Load detecting shaft (29) for advancing and retracting the nut plate (33) with respect to the pressure adjusting spring (25) according to the increase or decrease of the loaded weight of
In a load-responsive brake hydraulic control valve configured to rotate normally and reversely, a cylindrical chamber (28) that rotatably accommodates a nut plate (33) is formed in a casing (3), and this cylindrical chamber (2
An adjustable fixing plate (32), which is connected to the nut plate (33) via a connecting means (35) so as to be displaceable in the axial direction, is rotatably fitted in 8), while the casing (3) is in a predetermined position relative thereto. And a temporary fixing means (39) for temporarily fixing the load detecting shaft (29) and a fixing means (44) for fixing the adjustment fixing plate (32) at an arbitrary rotational position. , Load response type brake hydraulic control valve. 2. The connection according to claim 1, wherein the connecting means (35) is erected on one of the nut plate (33) and the adjusting and fixing plate (32) and extends parallel to the load detecting shaft (29). A load responsive brake hydraulic control valve comprising a pin (50) and a pin hole (51) formed in the other of the pins and into which the connecting pin (50) is slidably fitted. .