JPH11108230A - Differential pressure control valve, inspection method for the same, regulating method for the same, and vehicular brake device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To control pressure with high accuracy by suppressing change of attraction in association with movement of a needle. SOLUTION: This differential pressure control valve 1 is provided with a plunger 3 driven by a solenoid 2, a sleeve 4 for holding the plunger 3 slidably, a control piston 6 moved in association with movement of the plunger 3, and a guide 7 for holding the control piston 6 slidably. A magnet short structure is formed in such a constitution that a cylindrical projection part 21 is arranged on a lower end surface 3a of the plunger 3 freely to push-press the control piston 6, and a cylindrical recessed part 22 is arranged on an upper end surface 7a of the guide 7 freely to fit to the projection part 21. At the time of not- current carrying of the solenoid 2, the projection part 21 and the recessed part 22 are partially overlapped with each other at a parallel side surface. When current-carrying of the solenoid 2, the plunger 3 is moved in an arrow A direction, and the control piston 6 is moved in the same direction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a differential pressure control valve which is arranged, for example, in a pipeline of a vehicle brake device of a vehicle and adjusts a differential pressure of a brake fluid pressure, and a vehicle brake device.

[0002]

2. Description of the Related Art Conventionally, in a vehicle brake system including a brake fluid pipe and a control valve for opening and closing the pipe, when a brake pedal is depressed, a predetermined value is determined in accordance with the amount of depression and the depressing force. The braking force is set so as to be obtained.

In this type of vehicle brake device,
Increase the depression force when depressing the brake pedal, and increase the master cylinder pressure, and thus the wheel cylinder pressure,
In order to improve the braking force, a brake booster such as a vacuum booster is used.

However, since a vacuum booster or the like has a large physique and may be difficult to be mounted on a vehicle, a technique for replacing the same has been proposed. For example, Japanese Patent Application Laid-Open No. 8-230634 discloses a vacuum booster in which, when performing anti-skid control or traction control, control of a return pump, a switching valve, and a suction valve is performed depending on a signal indicating operation of a brake pedal. A technique has been proposed to take over the function of.

[0005]

However, in order to directly control the pressure on the wheel cylinder side, a differential pressure control valve, which is an on-off type solenoid valve, is used as the switching valve. , The suction force of the mover (the force for attracting the mover to the stator side) greatly changes, so that there has been a problem that the differential pressure cannot be controlled stably.

That is, in the conventional differential pressure control valve, when the mover moves, the distance (plunger stroke) between the mover and the stator changes as shown by the broken line in FIG. It has the characteristic that the amount of magnetic flux between it and the child changes greatly, and the attraction force also changes greatly.

Therefore, in the conventional differential pressure control valve, if the flow rate changes for some reason, the position of the mover changes in order to maintain the change in the flow rate, so that the suction force greatly changes. . When the suction force changes, the differential pressure also changes, resulting in a problem that the brake fluid pressure such as the wheel cylinder pressure cannot be precisely controlled.

In the conventional differential pressure control valve, as shown by a broken line in FIG. 2A, a differential pressure does not occur when the current applied to the solenoid is less than a predetermined value. Since the differential pressure is generated, there is also a problem that precise control of the brake fluid pressure cannot be performed when the applied current is equal to or less than a predetermined value.

Since the relationship between the plunger stroke and the suction force is determined according to the applied current as shown by the broken line in FIG. 2B, for example, when the applied current is 2 A, the plunger stroke is PS1, and Is within the movable range (actual use range), the mover suddenly moves so that the plunger stroke becomes PS0, and the suction force increases at a stretch (for example, changes from 0 to K1).

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has a differential pressure control valve and a vehicle brake device capable of performing high-precision pressure control by suppressing a change in suction force accompanying movement of a mover. The purpose is to provide.

[0011]

[Means for Solving the Problems]

(1) According to the first aspect of the present invention, in a differential pressure control valve that is disposed in a brake fluid pipeline and adjusts a differential pressure of a brake fluid pressure, the differential pressure control valve penetrates a magnetic flux generated by a solenoid, A movable element that is moved by the magnetic force, and a stator that is arranged in the moving direction of the movable element and through which a magnetic flux from the solenoid penetrates, and a magnetic flux in the moving direction of the movable element and the stator that accompanies the movement of the movable element. It has a magnetic short structure that suppresses fluctuations in the amount.

The differential pressure control valve according to the present invention is capable of generating a suction force for moving the mover by flowing a current of a solenoid, and setting a differential pressure of the brake fluid pressure according to the suction force. In this type of differential pressure control valve, when the distance between the mover and the stator changes, the amount of magnetic flux in the moving direction of the mover changes. For example, when the mover and the stator approach each other, the amount of magnetic flux increases and suction occurs. Although the force increases, if the suction force changes in this way, a stable differential pressure cannot be generated, and the differential pressure cannot be adjusted when a low current is applied. Therefore, in the present invention, a magnetic short-circuit structure is provided that suppresses a change in the amount of magnetic flux in the moving direction even when the mover moves.

Accordingly, as shown by the solid line in FIG. 1, for example, in the actual use area of the mover (plunger), a flat characteristic is realized so that the suction force does not change so much. In other words, when the distance between the mover and stator is large,
The suction force does not decrease, and even if the interval is small, the suction force does not suddenly increase.
Even if only one of them is close to flat, there is an effect in the corresponding area).

As a result, it is possible to prevent a large change in the suction force due to the distance between the mover and the stator, so that a stable differential pressure can be generated regardless of the position of the mover, and precise brake control can be performed. Can be realized. Further, in the present invention, as shown by the solid line in FIG. 2, for example, even if the current value applied to the solenoid is changed, at each current value, the suction force does not change much in the actual use region of the mover. Therefore, the attraction force can be set according to the value of the applied current, so that there is an effect that the differential pressure can be precisely adjusted particularly when the applied current is small.

(2) In the second aspect of the present invention, the magnetic short structure has a structure in which the amount of magnetic flux in a direction different from the moving direction changes between the mover and the stator as the mover moves. It is. For example, when the mover approaches the stator, the amount of magnetic flux in the moving direction does not increase, but the amount of magnetic flux increases in the direction perpendicular to the moving direction.

In this case, for example, even if the amount of magnetic flux in the direction perpendicular to the moving direction increases, the force for moving the mover, that is, the attraction force does not increase. Therefore, regardless of the position of the mover,
The suction force and thus the differential pressure can be set. (3) In the invention according to claim 3, the magnetic short structure is a concave portion or a convex portion provided on the mover and the stator, which can be fitted to each other, and the fitted state changes when the mover moves. I do.

The concave portion and the convex portion may be provided on either the mover or the stator as long as they are fitted to each other. Therefore, when the mover moves, the fitted state changes. . In this case, the amount of magnetic flux increases when the mover and the stator approach each other, but when the fitting state is deeper, the direction of the magnetic flux is greater in the vertical direction than in the moving direction. Therefore, when the mover approaches and separates from the stator, the change in the amount of magnetic flux in the moving direction is small, so the change in the attraction force is small and the change in the differential pressure is also small.

(4) According to the fourth aspect of the present invention, the concave portion and the convex portion have surfaces parallel to the moving direction. The present invention specifically shows a fitting state based on the shapes of the concave portion and the convex portion, and when having a surface parallel to the moving direction, a magnetic flux in a direction perpendicular to the moving direction is easily generated. Therefore, even when the mover moves, the change in the suction force is small and the change in the differential pressure is also small.

(5) According to the fifth aspect of the present invention, the concave portion and the convex portion have surfaces oblique to the moving direction. The present invention specifically shows a fitting state according to the shape of the concave portion and the convex portion, as in the case of the fourth aspect. Magnetic flux is easily generated. In this case, the effect may be less than that of claim 4, but similarly, even when the mover moves,
The change in the suction force is small, and the change in the differential pressure is also small.

(6) According to the sixth aspect of the present invention, even when the differential pressure control valve is off, the mover and the stator have a region overlapping in the direction perpendicular to the moving direction of the mover. That is, even when the solenoid of the differential pressure control valve is not energized, the mover and the stator partially overlap. Therefore, even when the plunger stroke is large, the suction force does not decrease.

(7) According to the seventh aspect of the present invention, the magnetic short structure has a structure in which the amount of magnetic flux between the yoke of the solenoid and the mover changes when the mover moves. Specifically, when the mover moves in the direction of the stator, the amount of magnetic flux between the yoke and the mover decreases with the movement (in addition,
When moving in the opposite direction, the amount of magnetic flux increases). That is, for example, when the mover approaches the stator,
Although the amount of magnetic flux between the mover and the stator increases and the attractive force increases, in the present invention, the amount of magnetic flux between the yoke and the mover changes (in this case, decreases), so the attractive force is reduced. It does not increase so much and the change in differential pressure is small.

(8) In the invention of claim 8, the differential pressure control valve is driven by current control according to the magnitude of the current supplied to the solenoid. In the present invention, the suction force can be changed as shown by the solid line in FIG. 2B by increasing or decreasing the value of the current supplied to the solenoid, so that the differential pressure can be precisely adjusted.

(9) According to the ninth aspect of the invention, the differential pressure control valve is driven by on-off duty control of a current supplied to the solenoid. By performing the on-off duty control of the current supplied to the solenoid, the suction force can be changed in the same manner as the current control for increasing or decreasing the current value, so that the differential pressure can be precisely adjusted.

(10) According to the tenth aspect of the present invention, a pressure loss applying mechanism for applying a pressure loss (back pressure) is provided downstream of the differential pressure control valve. For example, the well-known traction control (TRC
Control), vehicle turning control (VSC control), and power assist brake control (PAB control), the upstream side (wheel cylinder side) of the differential pressure control valve is high pressure and the downstream side (master cylinder side) is low pressure. Sometimes, for example, when the brake pedal is returned, when the temperature is high and the water content in the brake fluid is high near the communication hole where the valve body is seated, bubbles are generated in the brake fluid (aeration). Is generated), and when this aeration occurs, the braking performance is reduced.

Therefore, in the present invention, the occurrence of aeration is prevented by providing a pressure loss adding mechanism for adding a pressure loss (back pressure) downstream of the differential pressure control valve. That is, when the brake fluid changes from a high pressure to a low pressure (atmospheric pressure) at once, a negative pressure is temporarily generated, and aeration is easily generated. In the present invention, such a sudden change in the pressure is reduced (the negative pressure is reduced). A back pressure is applied downstream of the differential pressure control valve for the purpose of preventing the occurrence). Thereby, a sudden change in pressure can be reduced and occurrence of aeration can be suppressed, so that high braking performance can be ensured.

(11) According to the eleventh aspect, the pressure loss applying mechanism is an orifice. The present invention relates to the above-mentioned claim 10.
In this embodiment, an orifice is employed as a pressure applying mechanism. That is, by arranging the orifice on the downstream side of the differential pressure control valve, back pressure can be added, so that aeration can be prevented.

(12) In the twelfth aspect of the invention, the pressure loss applying mechanism is an auxiliary valve body urged by urging means (for example, a spring). The present invention exemplifies the invention of claim 10, and employs an auxiliary valve body (so-called mechanical valve) urged by urging means as a pressure applying mechanism.
That is, by arranging the mechanical valve on the downstream side of the differential pressure control valve, the back pressure can be applied by the urging force of a spring or the like, so that the occurrence of aeration can be prevented.

(13) According to the thirteenth aspect of the present invention, there is provided a vibration suppressing mechanism for suppressing vibration in the vicinity of the seating position of the valve element operated by the operation of the mover. For example, the TRC
When performing control, VSC control, and PAB control, when the upstream side of the differential pressure control valve is at a high pressure and the downstream side is at a low pressure, for example, when the brake pedal is returned, the high speed flow of the brake fluid causes When the valve body vibrates (in the vicinity of the seating position), aeration may occur.

Therefore, in the present invention, a vibration suppressing mechanism for suppressing vibration near the seating position of the valve element is provided. Thereby, occurrence of aeration can be prevented, and braking performance can be ensured. (14) According to a fourteenth aspect of the present invention, the vibration suppressing mechanism connects the mover and the valve body integrally.

The present invention exemplifies the invention of the thirteenth aspect, and may employ a structure in which a mover and a valve body are integrally connected as a vibration suppressing mechanism. In other words, if the valve body is a single body, it is usually lightweight and thus easily vibrated. However, if the mover and the valve body are integrally connected, the size of the connection body becomes long and the weight becomes large, so that the vibration is reduced. It is unlikely to occur. Thereby, the occurrence of aeration can be prevented.

(15) According to the fifteenth aspect of the invention, the vibration suppressing mechanism is configured to slidably support the valve body by the cylindrical body into which the valve body is fitted. The present invention exemplifies the invention of the thirteenth aspect, and as the vibration suppressing mechanism, a configuration in which the valve body is slidably supported by a tubular body in which the valve body is fitted.

That is, if the valve body is slidably supported from the outside of the valve body by the cylindrical body, it is difficult to vibrate even if high-speed brake fluid is applied to the valve body. Thereby, the occurrence of aeration can be prevented. (16) In the invention of claim 16, a lateral force influence reduction mechanism is provided for reducing the influence of a lateral urging force on the mover due to the magnetic force of the solenoid.

Since the mover is a magnetic material, the mover moves in the valve opening or valve closing direction (axial direction) by the magnetic force of the solenoid. The magnetic force not only moves the mover in the axial direction, but also moves the valve in the axial direction. Also acts in the lateral direction. However, the force acting in the lateral direction is not always stable if there is an interval between the mover and the solenoid. Therefore, when the current applied to the solenoid is increased or decreased, a desired opening / closing valve operation is not necessarily performed, and as a result, there is a problem that a desired differential pressure cannot be realized by the differential pressure control valve. That is, the increase or decrease of the current may cause hysteresis in the settable differential pressure.

Therefore, in the present invention, the influence of the lateral force due to the magnetic force applied to the mover is reduced by the lateral force effect reducing mechanism.
As shown in the figure, if the current value applied to the solenoid is determined,
The predetermined differential pressure can be uniquely set.

(17) According to the seventeenth aspect, the lateral force effect reducing mechanism is configured to slidably support the mover outside the magnetic path of the magnetic flux generated by the solenoid. The present invention exemplifies the invention of claim 16, wherein the lateral force effect reduction mechanism is provided outside the magnetic path of the magnetic flux of the solenoid,
A configuration in which the mover is slidably supported can be adopted.

In other words, if the mover is supported outside the magnetic path of the solenoid, the influence of the magnetic force of the solenoid is small, so that it is less affected by the lateral force. As a result, the hysteresis described above is eliminated. Thus, a fixed relationship between the applied current and the differential pressure can be ensured.

(18) According to the eighteenth aspect of the invention, the mechanism for reducing the influence of lateral force has a structure in which a non-magnetic member is arranged around the mover and the non-magnetic member is slidably supported. The present invention exemplifies the invention of claim 16, and as the lateral force effect reducing mechanism, a configuration in which a non-magnetic member is arranged around the mover and the non-magnetic member is slidably supported can be adopted. .

That is, since the slidably supported member is a non-magnetic material, it is naturally less affected by the magnetic force of the solenoid, and therefore less affected by the lateral force. As a result, the above-mentioned hysteresis can be eliminated, and a fixed relationship between the applied current and the differential pressure can be ensured.

(19) According to the nineteenth aspect of the present invention, a pressure loss reducing structure for reducing pressure loss when the valve is opened is provided at the tip of the needle of the valve body operated by the operation of the mover. For example, FIG.
As shown in FIG. 6 (a), in the case of a conventional valve body having a sharp pointed needle tip, pressure loss is likely to occur when the valve is opened.

Therefore, in the present invention, since the pressure loss reducing structure is provided at the tip of the needle, the pressure loss at the time of opening the valve can be reduced. By reducing the pressure loss, there is an advantage that a response delay at the time of releasing the brake can be improved. (20) According to the twentieth aspect, the pressure loss reducing structure is configured to obtuse the needle tip.

The present invention exemplifies the nineteenth aspect of the present invention.
As shown in (c), a configuration is adopted in which the tip of the needle is made obtuse. Thereby, pressure loss at the time of valve opening can be reduced. (21) According to the twenty-first aspect, the pressure loss reducing structure is configured to cut the tip of the needle flat.

The present invention exemplifies the invention of claim 19, and has a pressure loss reducing structure as shown in FIG.
As shown in (b), a configuration is adopted in which the tip portion of the needle is cut flat (for example, cut perpendicular to the valve element and the axial direction). Thereby, pressure loss at the time of valve opening can be reduced.

(22) In the invention of claim 22, the pressure loss reducing structure is configured to smoothly curve the tip of the needle. The present invention exemplifies the invention of claim 19, and employs, as a pressure loss reducing structure, a structure in which the tip of the needle is smoothly curved (and thus has an obtuse angle) as shown in FIG. 26 (d), for example. doing. Thereby, pressure loss at the time of valve opening can be reduced.

(23) The invention according to claim 23 is the invention according to claims 1 to
22. The method for inspecting a differential pressure control valve according to any one of 22., comprising a movable element, a valve element operated by the operation of the movable element, a spring for urging the valve element, and a valve element guide. A step of arranging a solenoid and a sleeve to be used for inspection on the outer periphery of the mover with respect to the basic structure of the differential pressure control valve, and measuring the pressing force of the valve at the tip of the valve by the magnetic force of the inspection solenoid. Arranging measuring means (for example, a load cell) to perform
Energizing the inspection solenoid and measuring the pressing force of the valve body at that time by a measuring means.

In the present invention, in order to check the performance of the basic structure including the mover, the valve element, the spring, and the guide, an inspection solenoid and a sleeve are attached to the basic structure.
It actually works. Specifically, an electric current is applied to the solenoid, and the pressing force of the valve element operated by the magnetic force generated in the solenoid at that time is measured by the measuring means.

As a result, the relationship between the applied current and the pressing force of the valve element can be known, and various adjustments such as the inventions of claims 24 to 28 described later are made in accordance with the measurement results.
A differential pressure control valve having a desired solenoid attraction force characteristic can be obtained. (24) The invention of claim 24 is the adjustment method of the differential pressure control valve according to any one of claims 1 to 22, wherein a current supplied to the solenoid and a pressing force of the valve element by a magnetic force of the solenoid are: The offset load of the spring that urges the valve body in the direction opposite to the pressing force is adjusted so as to satisfy the predetermined relationship.

For example, according to the twenty-third aspect of the present invention, when the relationship between the applied current and the pressing force (load) of the valve element as shown in FIG. 29 (measured value indicated by the solid line in the figure) is obtained,
By adjusting the offset load of the spring (for example, the return spring), it is possible to match the desired suction force characteristic of the solenoid (shown by a broken line in the figure).

(25) The twenty-fifth aspect of the present invention is the first aspect of the present invention.
22. The method for adjusting a differential pressure control valve according to any one of claims 22 to 22, wherein a gradient of a solenoid attraction force characteristic is set so that a current supplied to the solenoid and a pressing force of a valve body by a magnetic force of the solenoid satisfy a predetermined relationship. To adjust.

For example, when the relationship between the applied current and the pressing force (load) of the valve element as shown in FIG. 30 (measured value shown by the solid line in the figure) is obtained by the invention of claim 23,
For example, by adjusting the state of the magnetic path, it is possible to obtain a suction force characteristic (shown by a broken line in the drawing) of the solenoid having a desired gradient.

(26) The invention according to claim 26 is characterized in that:
22. The method for adjusting a differential pressure control valve according to any one of 22., wherein the current applied to the solenoid and the pressing force of the valve element due to the magnetic force of the solenoid satisfy a predetermined relationship, in a direction opposite to the pressing force. The offset load of the spring for biasing the valve body is adjusted, and the gradient of the solenoid attraction force characteristic is adjusted.

The present invention is a combination of the twenty-fourth and twenty-fifth aspects of the present invention, whereby the offset force is adjusted to translate the attraction force characteristic of the solenoid in parallel as shown in FIG. In addition, by adjusting the state of the magnetic path to change the gradient of the attractive force characteristic, a desired attractive force characteristic can be realized.

(27) According to the twenty-seventh aspect, the adjustment of the offset load of the spring is performed by changing the thickness of the adjustment shim for changing the offset length of the spring. The present invention
It exemplifies the invention of claim 24 or 26,
The offset load of the spring is adjusted by changing the thickness of the adjustment shim that changes the offset length of the spring.

In other words, by pressing the adjustment shim between the spring and another member, the pressing force of the spring changes.
By changing the thickness of the adjustment shim, the offset load can be changed. (28) According to the twenty-eighth aspect, the offset load of the spring is adjusted by changing the engagement combination position of the ratchet for changing the offset length of the spring.

According to the present invention, the offset load of the spring is adjusted by changing the engagement combination position of the ratchet for changing the offset length of the spring. That is, by changing the relative distance between the spring and the other member by changing the engagement state of the ratchet mechanism in a stepwise manner, the pressing force of the spring changes, so that the combination of the ratchet engagement is changed. Thus, the offset load can be changed.

(29) According to the twenty-ninth aspect, the gradient of the solenoid attraction force characteristic is adjusted by changing the adjustment plate for changing the state of the magnetic path. The present invention exemplifies the invention of claim 25 or 26, wherein the gradient of the solenoid attraction force characteristic is adjusted by changing the adjustment plate that changes the state of the magnetic path.

For example, by changing the adjustment plate for changing the width of the path (magnetic path) through which the magnetic flux passes, the magnetic force can be adjusted without changing the applied current.
The gradient of the suction force characteristic of the solenoid can be changed. (30) In the invention of claim 30, the gradient of the solenoid attraction force characteristic is adjusted by changing the air gap between the mover and the stator to change the state of the magnetic path.

The present invention exemplifies the invention of the twenty-fifth or twenty-fifth aspect, wherein the solenoid attraction force characteristic is changed by changing the air gap between the mover and the stator which changes the state of the magnetic path. Adjust the gradient of For example, by changing the press-fit position of the valve seat, the air gap on the magnetic circuit can be adjusted, and the magnetic force can be adjusted without changing the applied current, whereby the gradient of the attraction force characteristic of the solenoid can be changed.

(31) According to the thirty-first aspect, at the time of vehicle braking, brake fluid pressure generating means (for example, a master cylinder)
When brake fluid pressure is generated at, this brake fluid pressure
The power is transmitted to a wheel braking force generating means (for example, a wheel cylinder) to generate a wheel braking force. Also, if necessary,
The brake fluid is moved from the brake fluid pressure generating means to the wheel braking force generating means by the brake fluid moving means (for example, a pump).

In this vehicle brake device, the differential pressure control valve according to any one of claims 1 to 22 is disposed in a pipeline between the brake fluid pressure generating means and the wheel braking force generating means. The brake fluid pressure on the side of the wheel braking force generating means divided by the differential pressure control valve can be increased.

That is, the brake fluid is moved toward the wheel braking force generating means by the brake fluid moving means in a state where the pipeline is divided by the differential pressure control valve, thereby increasing the brake fluid pressure on the wheel braking force generating means side. At the same time, the differential pressure of the brake fluid pressure between the brake fluid pressure generating means and the wheel braking force generating means can be adjusted by the differential pressure control valve.

(32) According to the thirty-second aspect of the present invention, a brake fluid pressure generating means (for example, a master cylinder) is provided during braking of the vehicle.
When brake fluid pressure is generated at, this brake fluid pressure
The power is transmitted to a wheel braking force generating means (for example, a wheel cylinder) to generate a wheel braking force.

In this vehicle brake device, the differential pressure control valve according to any one of claims 1 to 22 is disposed in a pipeline between the brake fluid pressure generating means and the wheel braking force generating means. The brake fluid pressure on the side of the wheel braking force generating means divided by the differential pressure control valve can be reduced.

That is, since the differential pressure control valve is capable of adjusting the differential pressure of the brake fluid pressure on both sides of the pipeline in which the differential pressure control valve is disposed, the wheel brake force generating means is controlled by the brake fluid pressure generating means. If the differential pressure control valve is connected so that the brake fluid pressure on the side becomes smaller, the brake fluid pressure on the wheel braking force generating means side can be reduced more than on the brake fluid pressure generating means side.

[0064]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of a differential pressure control valve and a vehicle brake device according to the present invention will be described below by way of example (embodiment).
This will be described in detail with reference to the drawings. (Example 1) a) First, a differential pressure control valve will be described.

As shown in FIG. 3, the differential pressure control valve 1 of this embodiment
Is an electromagnetic valve driven by energizing the solenoid 2. The differential pressure control valve 1 includes a mover (plunger) 3 driven by a solenoid 2 and a plunger 3.
A sleeve 4 that covers the outer periphery of the plunger 3 to slidably hold the plunger 3, a rod-shaped control piston 6 that is pressed and moves with the movement of the plunger 3, and slides the control piston 6 over the outer periphery of the control piston 6. And a guide 7 movably held.

Among these, the amount of magnetic flux (magnetic flux amount) indicated by a broken line in the figure changes in proportion to the magnitude of the applied current, and the magnetic flux penetrates the solenoid 2 so as to cover the outer periphery thereof. Yoke 8 is arranged. The sleeve 4
Is a non-magnetic stainless steel, and the plunger 3
In order to restrict the movement in the direction of arrow B to a predetermined amount, FIG.
Is closed at the upper end, and the lower end is fitted over the upper end of the guide 7.

The control piston 6 is a body valve (valve element) made of non-magnetic stainless steel, and is located at the large diameter portion 6a at the upper end, the small diameter portion 6b at the lower end, and further on the distal end side of the small diameter portion 6b. It is composed of a conical needle tip 6c. The needle tip 6c is connected to the guide 7
The communication hole 13 (which is a valve portion orifice) of the cylindrical valve seat 12 fitted inside the hollow portion 11 is closed to close the flow path of the brake fluid. The control piston 6 is urged by a spring 14 in the direction of arrow B (ie, the valve opening direction).

The guide 7 is a stator on the side where the plunger 3 is sucked. The hollow portion 11 in which the control piston 6 slides communicates with the pump 36 and the wheel cylinder 32 shown in FIG. 5 through the distal end communication hole 16 at the lower end thereof, and also communicates with the master cylinder 31 through the side communication hole 17.
Side (see FIG. 5).

In particular, in the present embodiment, as shown in FIG.
a has a cylindrical convex portion 21 capable of pressing the control piston 6.
Is provided, and a concave portion 22 is provided on the upper end surface 7a of the guide 7 so as to be fittable with the convex portion 21.

As shown in FIG. 4 (a), when the solenoid 2 is not energized, the lower end face 3a of the plunger 3 and the upper end face 7a of the guide 7 are set so as to keep a constant interval. In this case, the convex portion 21 and the concave portion 22 slightly overlap each other on their parallel side surfaces. The distance between the lower end surface 3a and the upper end surface 7a is the maximum value (PS1) of the plunger stroke, which is called a gap.

As shown in FIG. 4B, when the solenoid 2 is energized, the plunger 3 is moved downward (in the direction of arrow A;
(The valve closing direction) to move the control piston 6 in the same direction. As a result, the piston 6 is seated on the valve seat 12,
The movement of the plunger 3 in the direction of arrow A is set to stop. By this seating, the distance between the lower end surface 3a and the upper end surface 7a becomes the minimum value of the plunger stroke (PS0).

B) Next, a description will be given of a vehicle brake device using the differential pressure control valve 1 having the above-described configuration. still,
Here, the configuration of one of the four wheels will be described as an example. As shown in FIG. 5, the differential pressure control valve 1 of the present embodiment includes a master cylinder (M / C) 31 and a wheel cylinder (W / C).
C) is connected to a pipe line 33 which connects to the master cylinder 31 and the discharge side is set to the wheel cylinder 32 side. , A pump 36 is arranged. Note that a brake pedal 38 is connected to the master cylinder 31 via a brake booster 37 that boosts the pedaling force.

Therefore, in this vehicle brake device, the wheel cylinder pressure (W / C pressure) is reduced from the master cylinder pressure (M / C pressure) by operating the pump 36 while the differential pressure control valve 1 is operated. Can be increased. Although not shown, the vehicle brake device uses an electronic control unit (ECU) to detect various sensors, for example, a wheel speed sensor for detecting wheel speed, a vehicle speed sensor for detecting vehicle speed, and a master cylinder pressure. Master cylinder pressure sensor, wheel cylinder pressure sensor for detecting wheel cylinder pressure, negative pressure sensor for detecting negative pressure introduced into the brake booster 37, tread force sensor for detecting the tread force of the brake pedal 38, load of loaded luggage, etc. Various solenoid valves and pumps 3 based on signals from load sensors and the like that detect
By driving the actuators 6 and the like, various controls described later are executed.

C) Next, the basic operation of the differential pressure control valve 1 will be described. When the wheel cylinder pressure is increased from the master cylinder pressure, that is, when a differential pressure is generated between the master cylinder pressure and the wheel cylinder pressure, the pump 36 is operated as shown in FIG. The brake fluid is sent from the master cylinder 31 side to the wheel cylinder 32 side, and the solenoid 2 of the differential pressure control valve 1 is energized to operate the differential pressure control valve 1.

When the solenoid 2 is energized, the plunger 3 moves downward (in the direction of arrow A) in FIG. 5 against the urging force of the spring 14 by electromagnetic force (attraction force F). To sit down. When this seat is seated, the following equation (1) is established.

A (P ₂ −P ₁ ) = F (1) where A is the pressure receiving area of the communication hole of the valve seat P ₂ ; wheel cylinder pressure P ₁ ; master cylinder pressure Therefore, the solenoid 2 is energized and the pump is energized. By operating the wheel 36, the wheel cylinder pressure (P ₂ ) can be increased as in the following equation (2).

P ₂ = P ₁ + F / A (2) Further, as will be described in detail later, an attractive force is generated exactly in proportion to the current value (I) applied to the solenoid 2. Therefore, from the above equation (2), as shown in FIG. 6, the relationship between the master cylinder pressure and the wheel cylinder pressure can be adjusted by changing the current value, thereby changing the suction force.

Next, the reason why the suction force is generated in proportion to the value of the current supplied to the solenoid 2 will be described. Normally, the magnetic flux passing through the plunger 3 and the guide 7 changes as the plunger 3 moves. In other words, immediately after the solenoid 2 is energized, the plunger 3 and the guide 7 are slightly separated from each other, so that the amount of magnetic flux passing through the plunger 3 and the guide 7 is small, but thereafter, as the plunger 3 approaches the guide 7, The amount of magnetic flux passing through the plunger 3 and the guide 7 increases.

However, in the case of this embodiment, the plunger 3
And the guide 7 have a convex portion 21 and a concave portion 2 fitted to each other.
When the plunger 3 approaches the guide 7, the overlapping area on the parallel side surfaces of the convex portion 21 and the concave portion 22 increases since the plunger 2 is provided. Therefore, FIGS. 7 (a) to 7 (c)
Even when the plunger 3 approaches the guide 7, the amount of magnetic flux in the direction of movement of the plunger 3 (in the direction of arrow A) does not increase, and the amount of magnetic flux between the convex portions 21 and the concave portions 22 is increased. The amount of magnetic flux in the direction perpendicular to the moving direction (radial direction) increases.

That is, the change of the magnetic flux accompanying the movement of the plunger 3 is that the amount of magnetic flux in the radial direction only changes without changing the amount of magnetic flux in the moving direction. Therefore, even when the plunger 3 approaches the guide 7, the suction force for sucking the plunger 3 does not increase, and the plunger 3 is always sucked toward the guide 7 with a stable force. Therefore, the control piston 6 is urged downward with a constant force,
The differential pressure control valve 1 can always generate a constant differential pressure.

This is shown by the solid line in FIG. 1. In this embodiment, since the suction force does not change even if the plunger stroke changes, the relation that a certain master cylinder pressure always becomes a predetermined wheel cylinder pressure is obtained. Can be held. Further, since the suction force can be adjusted by the current value supplied to the solenoid 2, by adjusting the current value, the master cylinder pressure and the wheel pressure can be adjusted within a predetermined control range as shown in FIG. The relationship with the cylinder pressure can be set arbitrarily.

Further, as shown by the solid line in FIG. 2, even when the current value is low in the actual use area, the suction force can be set according to the current value, so that the differential pressure can be controlled even at a low current value. Can be performed precisely. d) Next, control processing in the vehicle brake device using the above-described differential pressure control valve 1 will be described with reference to the flowcharts of FIGS.

Here, the pressure amplification assist brake control (PAB) for increasing the braking force by increasing the wheel cylinder pressure from the master cylinder pressure will be described. First, in step 100 of FIG. 8, the brake pedal 38 is depressed, and a stop switch (not shown) is turned on (ON).
Is determined. Here, if the determination is affirmative, the process proceeds to step 110, while if the determination is negative, the process is temporarily terminated.

In step 110, it is determined whether or not the conditions for performing the pressure amplification assist brake control have been satisfied. If a positive determination is made here, the process proceeds to step 120,
On the other hand, if a negative determination is made, the present process is ended once. The determination conditions include, for example, whether the pedal stroke speed is equal to or greater than a predetermined value (XAmm / sec), whether the pedaling force change speed is equal to or greater than a predetermined value (XBkgf / sec), and the like.

In step 120, a pump motor (not shown) is turned on to operate the pump 36. In the following step 130, a target oil pressure is calculated from the pedaling force. In the following step 140, a current value to be applied to the differential pressure control valve 1 is calculated from the target oil pressure. Alternatively, a current value (or duty ratio) corresponding to the current value is calculated.

At step 150, the current applied to the solenoid 2 is controlled based on the calculated current value (or duty ratio) to drive the differential pressure control valve 1. In the following step 160, it is determined whether or not an end condition for ending this pressure amplification assist brake control has been satisfied. Here, if a positive determination is made, the process proceeds to step 170,
On the other hand, if a negative determination is made, the process returns to step 130. The determination conditions include, for example, whether the pedaling force reduction amount exceeds a predetermined value XC, whether the pedaling force falls below a predetermined value XD, and the like.

At step 170, the power supply to the solenoid 2 is turned off (OFF), and the operation of the differential pressure control valve 1 is stopped. Thereby, the differential pressure control valve 1 is completely opened. In the following step 180, the pump motor is turned off, the operation of the pump 36 is stopped, and the process is temporarily terminated.

Thus, the above control makes it possible to increase the wheel cylinder pressure above the master cylinder pressure to increase the braking force. Next, control when the brake booster 37 that boosts the depression force of the brake pedal 38 fails will be described.

First, the brake booster 37 is driven by the difference between the atmospheric chamber for introducing the atmosphere and the negative pressure chamber for introducing the negative pressure. In step 200, the pressure (internal pressure) of the negative pressure chamber is set to a predetermined value. It is determined whether the value exceeds the value (−XEmmHg). Here, if a positive determination is made, it is determined that the necessary internal pressure has not been obtained, that is, the brake booster 37 has failed, and the process proceeds to step 210. On the other hand, if a negative determination is made, the brake booster 37 is determined to be normal, and this process is once ended.

In step 210, the brake pedal 38
Is determined to determine whether or not the stop switch is turned on. Here, if an affirmative determination is made, the process proceeds to step 220, while if a negative determination is made, the present process is temporarily terminated. In step 220, the pump motor is turned on and the pump 3
Activate 6.

In the following step 230, the target oil pressure is calculated from the pedaling force. In the following step 240, a current value to be applied to the differential pressure control valve 1 is calculated from the target oil pressure. Or,
The duty ratio of the current corresponding to the current value is calculated.
In the following step 250, the current applied to the solenoid 2 is controlled based on the calculated current value (or duty ratio) to drive the differential pressure control valve 1.

In step S260, it is determined whether an ending condition for ending the control when the brake booster 37 has failed is satisfied. Here, if a positive determination is made, the process proceeds to step 270, while if a negative determination is made, the process returns to step 220. The determination condition includes, for example, whether or not the pedaling force is equal to or less than a predetermined value (XF).

In step 270, the power supply to the solenoid 2 is turned off, and the operation of the differential pressure control valve 1 is stopped. In the following step 280, the pump motor is turned off and the pump 3
The operation of Step 6 is stopped, and the process is temporarily terminated.

Therefore, when the brake booster 37 fails due to the above-described control, the wheel cylinder pressure is increased to be higher than the master cylinder pressure, so that the braking force is reduced in place of the boosting action using the differential pressure of the brake booster 37. Can be enhanced. Further, by using the above-described vehicle brake device, a high G
The control of the assisting, that is, the control of the boosting action can be performed in a region where the pedaling force is high and the assisting force of the brake booster 37 is used up.

Since the control of the high G assist is almost the same as the control shown in FIG. 8, the detailed explanation is omitted, but the control execution condition and the step 1 in step 110 of FIG.
60 control end conditions are different. That is, as the control execution condition, a condition such as whether the master cylinder pressure exceeds a predetermined value (XGbar) or whether the differential pressure in the brake booster 37 falls below a predetermined value (XHmmHg) can be adopted.

The control termination condition is whether the master cylinder pressure is lower than a predetermined value (XGbar) or the differential pressure in the brake booster 37 is lower than a predetermined value (XHmmH).
g) can be adopted. Like this
In the present embodiment, since the plunger 3 and the guide 7 are provided with a magnetic short-circuit structure including a convex portion 21 and a concave portion 22 which are fitted to each other, even when the solenoid 2 is energized and the plunger 3 is moved, the attraction force is increased. Does not change. Therefore, the differential pressure control valve 1 can precisely set the differential pressure from a low current value to a high current value according to the current value applied to the solenoid 2.

Further, since the differential pressure can be accurately set by the differential pressure control valve 1 as described above, in the vehicle brake device using the differential pressure control valve 1, the pressure amplification assist brake control and the loss of the brake booster 37 are performed. The control at the time of falling and the control of the high G assist can be suitably performed.

(Embodiment 2) Next, Embodiment 2 will be described, but the description of the same parts as in Embodiment 1 will be omitted or simplified. In the present embodiment, the differential pressure control valve of the first embodiment is applied to another vehicle brake device.

[0099] This vehicular brake device is a known anti-skid control (ABS) or traction control (TRC).
Control (VS) to control the vehicle behavior at the time of turning
This is a vehicle brake device capable of performing C).
As shown in FIG. 10, the vehicle brake device has a tandem-type master cylinder 41, and a brake pedal 43 is connected to the master cylinder 41 via a brake booster 42.

The master cylinder 41 is connected to a master reservoir 46, and is connected to a hydraulic control circuit 50 which is composed of two hydraulic systems of X piping (diagonal piping) and adjusts a brake hydraulic pressure. 50
Is composed of a first hydraulic pipe 51a and a second hydraulic pipe 51b.

In the hydraulic control circuit 50, a front right (FR) wheel cylinder 55 and a rear left (RL) wheel cylinder 56 are communicated via a first hydraulic pipe 51a. A wheel cylinder 57 for the right rear (RR) wheel and a wheel cylinder 58 for the front left (FL) wheel are communicated via the second hydraulic pipe 51b.

The first hydraulic piping 51a controls the well-known pressure increase control valve 61 and the pressure reduction control valve 65 for controlling the oil pressure of the wheel cylinder 55 of the FR wheel, and controls the oil pressure of the wheel cylinder 56 of the RL wheel. A pressure increase control valve 62 and a pressure reduction control valve 66 for controlling the oil pressure of the wheel cylinder 57 of the RR wheel are provided in the second hydraulic pipe 51b. A pressure increase control valve 64 and a pressure decrease control valve 68 for controlling the oil pressure of the wheel cylinder 58 of the FL wheel are provided.

Here, the first hydraulic piping 51a will be described. The master cylinder 41 is controlled by the pressure increase control valves 61 and 62.
A differential pressure control valve 71 similar to that of the first embodiment is disposed on the side. By the differential pressure control valve 71, the (SRC valve 74
When the hydraulic pump 78 is driven (in the open state), the hydraulic pressure on the hydraulic path 75a side can be made higher by an arbitrary pressure than the master cylinder 41 side.

Further, a reservoir 76 for temporarily storing the brake oil discharged from each of the pressure reducing control valves 65 and 66 and a hydraulic pump 78 for pumping the brake oil to the hydraulic path 75a are provided in the first hydraulic pipe 51a. Is provided. still,
A damper 87 that suppresses the pulsation of the internal hydraulic pressure is provided on the discharge path of the brake oil from the hydraulic pump 78.

The first hydraulic pipe 51a is provided with a hydraulic path 79a for directly supplying brake oil from the master cylinder 41 to the hydraulic pump 78 when pressurizing the wheel cylinder pressure. Is a cut valve (SRC) that opens and closes the hydraulic path 79a.
A valve 74 is provided.

On the other hand, the first hydraulic pipe 51b is
Similarly to the hydraulic pipe 51a, the pressure increase control valves 63 and 64, the pressure reduction control valves 67 and 68, the differential pressure control valve 72, the reservoir 77, the hydraulic pump 79, the damper 88, the SRC valve 75, and the like are provided at similar locations. ing. The two hydraulic pumps 78, 7
9 is configured to be connected to and driven by the electric pump motor 81.

B) Next, the control processing in this embodiment will be described with reference to the flowchart of FIG.
Here, the TRC control will be described. In step 300 of FIG. 11, the brake pedal 43 is depressed,
It is determined whether a stop switch (not shown) has been turned off. Here, if a positive determination is made, the process proceeds to step 310, while if a negative determination is made, the present process is temporarily terminated.

At step 310, the drive wheel speed Va
Is higher than the rolling wheel speed Vb, that is, whether the slip state is excessive. Here, if the determination is affirmative, the process proceeds to step 320, while if the determination is negative, the present process is temporarily terminated. In step 320, the pump motor 81 is turned on to operate the pumps 78 and 79.

In the following step 330, a solenoid (not shown) is energized to control the differential pressure control valves 71 and 72, the SRC valve 7
4,75 are driven. In the following step 340, the pressure increase control valves 61 to 64 and the pressure decrease control valves 65 to 68 are controlled,
The driving wheel speed Va is controlled.

In the following step 350, it is determined whether or not the drive wheel speed Va is equal to the rolling wheel speed Vb. Here, if a positive determination is made, the process proceeds to step 360,
On the other hand, if a negative determination is made, the routine proceeds to step 340. In step 360, the pump motor 81 is turned off, and the operations of the pumps 78 and 79 are stopped.

In the following step 370, the power supply to the solenoid is turned off, and the differential pressure control valves 71 and 72, the SRC valve 7
The operations of Steps 4 and 75 are stopped, and the present process is temporarily ended. As described above, in the present embodiment, since the differential pressure control valves 71 and 72 are used in the above-described vehicle brake device, various controls such as TRC control are performed by controlling the current applied to the solenoids of the differential pressure control valves 71 and 72. By adjusting, it can be performed precisely.

(Embodiment 3) Next, Embodiment 3 will be described, but the description of the same parts as in Embodiment 1 will be omitted or simplified. In this embodiment, the connection of the differential pressure control valve of the first embodiment is reversed to be disposed in the vehicle brake device, so that the brake fluid pressure on the front wheel side can be made higher than on the rear wheel side. .

A) As shown in FIG. 12, in the vehicle brake system of this embodiment, the differential pressure control valve 91 is disposed in a pipe 94 connecting the master cylinder 92 and the wheel cylinder 93 on the rear wheel side. The front-wheel-side wheel cylinder 94 is connected to a pipe 95 branched from the pipe 94.

In this embodiment, in particular, the front end communication hole 97 (high pressure side) of the differential pressure control valve 91 is connected to the master cylinder 92 side and the front wheel wheel cylinder 94 side, while the side communication of the differential pressure control valve 91 is performed. A hole 98 (low pressure side) is connected to the wheel cylinder 93 side of the rear wheel.

B) Next, the operation of the vehicle brake device will be described. When the solenoid (not shown) is energized to operate the differential pressure control valve 91, as shown in FIG. 13, the relationship between the master cylinder pressure and the wheel cylinder pressure on the rear wheel side is determined according to the current value applied to the solenoid. Is set.

Therefore, when the differential pressure control valve 91 is actuated when the brake pedal 99 is depressed, the master cylinder pressure is transmitted to the front wheel side wheel cylinder 94 as it is, as shown in FIG. The brake fluid pressure on the rear wheel side can be set arbitrarily lower than that on the rear side.

Therefore, for example, during braking, the so-called front-wheel leading lock (when the wheels are locked) can be realized by increasing the brake fluid pressure on the front wheels rather than the rear wheels, and the braking of the locked vehicle can be more stabilized. Can be done. Further, the difference between the brake fluid pressure on the rear wheel side and the brake fluid pressure on the front wheel side can be arbitrarily set according to the magnitude of the current applied to the solenoid. By setting the differential pressure, the front-rear braking force distribution can be set so that the maximum braking force of the vehicle can be exerted, thereby increasing the stability of the vehicle during braking and greatly improving the braking performance.

C) Next, control processing in the vehicle brake device will be described with reference to the flowchart of FIG. This control is a control for adjusting the braking force distribution. At step 400 in FIG. 14, the load amount of the vehicle is detected based on, for example, a signal from a load sensor.

In the following step 410, it is determined whether or not a brake switch (not shown) is turned on. If the determination is affirmative, the process proceeds to step 420, while if the determination is negative, the present process is temporarily terminated. In step 420, the pedaling force is detected based on the signal from the pedaling force sensor.

In step 430, a target oil pressure is calculated based on the pedaling force and the loaded state. In the following step 440, a current value (or a duty ratio thereof) to be applied to the solenoid of the differential pressure control valve 91 is calculated based on the target oil pressure and the pedaling force. In the following step 450, the differential pressure control valve 91 is driven based on the calculated current value (or its duty ratio).

In the following step 460, it is determined whether or not the brake switch is on. If the determination is affirmative, the process returns to step 410, while if the determination is negative, the process proceeds to step 470. In step 470, the solenoid is turned off, the driving of the differential pressure control valve 91 is stopped, and the process is once ended.

That is, with such control, excellent braking performance can be exhibited with a suitable distribution of braking force.
Further, by performing the braking force distribution in this manner, even when, for example, the load on the vehicle changes, the same braking force can be realized with the same pedaling force.

(Embodiment 4) Next, Embodiment 4 will be described, but the description of the same parts as in Embodiment 1 will be omitted or simplified. This embodiment differs from the first embodiment in the magnetic short-circuit structure of the differential pressure control valve.

As shown in FIG. 15A, in the differential pressure control valve 101 according to the present embodiment, the protrusion 104 at the lower end of the plunger 103 fitted inside the sleeve 102 has the inside of the plunger 103 and the guide 105. Control piston 10 fitted
A convex side tapered portion 104a is formed which is inclined from the moving direction (vertical direction in FIG. 6). On the other hand, a concave taper portion 108a parallel to the convex taper portion 104a is formed in the concave portion 108 at the upper end of the guide 105. Thereby, the magnetic short structure shown in the figure is formed.

In the differential pressure control valve 101 of this embodiment,
The amount of magnetic flux increases due to the downward movement of the plunger 103 in the figure, and the increase is the amount of magnetic flux between the convex taper portion 104a and the concave taper portion 108a, and the magnetic flux in the moving direction of the plunger 103. The amount does not increase much.

Accordingly, since the suction force does not increase due to the movement of the plunger 103, the differential pressure can be set precisely by the differential pressure control valve 101 as in the first embodiment. (Embodiment 5) Next, Embodiment 5 will be described, but the description of the same parts as in Embodiment 1 will be omitted or simplified.

This embodiment is different from the first embodiment in the magnetic short-circuit structure of the differential pressure control valve. As shown in FIG. 15B, in the differential pressure control valve 111 of the present embodiment, a cylindrical concave portion 114 is provided at the lower end of the plunger 113 fitted inside the sleeve 112, and the upper end of the guide 115 is provided at the upper end of the guide 115. Is provided with a cylindrical convex portion 116, and the convex portion 11
6, the control piston 117 is attached to the guide 115.
Is fitted inside. Thereby, the magnetic short structure shown in the figure is formed.

In the differential pressure control valve 111 of this embodiment,
The amount of magnetic flux increases due to the downward movement of the plunger 113 in the figure. The increase is the amount of magnetic flux between the concave portion 114 and the convex portion 116, and the amount of magnetic flux in the moving direction of the plunger 113 increases so much. Nothing.

Therefore, since the suction force does not increase due to the movement of the plunger 113, the differential pressure can be set precisely by the differential pressure control valve 111 as in the first embodiment. (Embodiment 6) Next, Embodiment 6 will be described, but the description of the same parts as in Embodiment 1 will be omitted or simplified.

This embodiment is different from the first embodiment in the magnetic short-circuit structure of the differential pressure control valve. As shown in FIG. 15C, in the differential pressure control valve 121 of this embodiment, the plunger 123 fitted inside the sleeve 122
24, the plunger 123 is provided at its lower end with a columnar projection 125 having a conical tip. On the other hand, the hollow portion 127 of the guide 126 is provided with a step 128 corresponding to the conical portion of the convex portion 125. Thereby, the magnetic short structure shown in the figure is formed.

In the differential pressure control valve 121 of this embodiment,
When the plunger 123 moves downward in the drawing, the amount of magnetic flux increases. The increase is the amount of magnetic flux between the tip of the convex portion 125 and the step 128, and the amount of magnetic flux in the moving direction of the plunger 123 is It does not increase much.

Therefore, since the suction force does not increase due to the movement of the plunger 123, the differential pressure can be set precisely by the differential pressure control valve 121, as in the first embodiment. (Embodiment 7) Next, Embodiment 7 will be described, but the description of the same parts as in Embodiment 1 will be omitted or simplified.

This embodiment is different from the first embodiment in the magnetic short-circuit structure of the differential pressure control valve. As shown in FIG. 15D, in the differential pressure control valve 131 of this embodiment, the lower end of the plunger 133 fitted inside the sleeve 132 is flat without any irregularities. On the other hand, the control piston 13
The upper end of the guide 135 in which 4 is fitted is also flat.

In particular, in the present embodiment, substantially the entire sleeve 132 is made of a magnetic material, but a non-magnetic material is annularly arranged at a part of the lower end side. That is, when the plunger 133 moves upward, the position of the lower end of the plunger 133 and the position of the lower end of the non-magnetic material are set to substantially the same position. Thereby, the magnetic short structure shown in the figure is formed.

In the differential pressure control valve 131 of this embodiment,
When the plunger 133 moves downward in the figure, the amount of magnetic flux increases. The amount of the increase is the amount of magnetic flux between the lower part of the plunger 133 and the lower part 132a of the magnetic material of the sleeve 132, and the moving direction of the plunger 133. Does not increase so much.

Therefore, since the suction force does not increase due to the movement of the plunger 133, the differential pressure can be set precisely by the differential pressure control valve 131, as in the first embodiment. (Eighth Embodiment) Next, an eighth embodiment will be described, but the description of the same parts as in the first embodiment will be omitted or simplified.

This embodiment is different from the first embodiment in the magnetic short-circuit structure of the differential pressure control valve. As shown in FIG. 16, in the differential pressure control valve 141 of this embodiment, a solenoid 144 is disposed outside a sleeve 143 in which the plunger 142 is fitted, and a yoke 145 is provided so as to cover the outer periphery of the solenoid 144. Are located.

In particular, in the present embodiment, the upper part of the yoke 145 and the upper part when the plunger 142 moves upward in the figure are set to be substantially the same. Thereby, the magnetic short structure shown in the figure is formed. In the differential pressure control valve 141 of the present embodiment, as shown in FIG. 17A, when the plunger is located in the upper part of the figure, the amount of magnetic flux passing through the yoke 145 and the plunger is large. As shown in FIG. 17B, when the plunger 142 moves downward in the figure, the yoke 145 and the plunger 1
42, the amount of magnetic flux passing therethrough decreases.

Therefore, the amount of magnetic flux between the plunger 142 and the guide 146 should normally increase when the plunger 142 moves downward in FIG. 16, but in the present embodiment, the amount of magnetic flux in FIG. As shown in ()), the amount of magnetic flux in the magnetic short-circuit structure decreases, so that the entire amount of magnetic flux indicated by the broken line in FIG. Therefore, since the suction force does not increase, the differential pressure can be accurately set by the differential pressure control valve 141, as in the first embodiment.

(Embodiment 9) Next, Embodiment 9 will be described, but the description of the same parts as in Embodiment 1 will be omitted or simplified. In this embodiment, an orifice is disposed downstream of the differential pressure control valve as a pressure loss adding mechanism for adding a pressure loss.

A) First, the configuration of the differential pressure control valve of this embodiment will be described. As shown in FIG. 18, the differential pressure control valve 151 of this embodiment has a magnetic short-circuit structure similar to that of the first embodiment, and also urges the plunger 152, which is a magnetic mover, and the plunger 152 by magnetic force. A solenoid 153, a control piston 154 as a valve body,
A guide 156 in which the control piston 154 is fitted, and a valve seat 1 on which the needle tip 155 of the control piston 154 is seated.
57, and a spring (return spring) 158 for urging the control piston 154 upward in the drawing against the urging force of the solenoid 153.

In particular, in this embodiment, the plunger 152 and the control piston 154 are integrally connected by a connecting pin 159. Therefore, both 152 and 154 always move up and down integrally. In this embodiment, the pump side (and the wheel cylinder side) and the control piston 15
4 is connected to the hollow portion 161 of the guide 156 by the main communication passage 163 having the upstream orifice 162. Moreover, the wheel cylinder side and the master cylinder side are connected via a check valve 164.

Further, the hollow portion 161 communicates with the master cylinder through the downstream communication passages 167 and 168. The downstream communication passages 167 and 168 communicate with the downstream side of the differential pressure control valve 151. To add pressure loss (back pressure) at
Downstream orifices 166, 169 are provided.

The flow path leading to the main communication path 163 and the downstream communication paths 167, 168 are provided in the filters 171, 17 respectively.
2 are arranged. The guide 156 is fixed to the housing 174, and a frame 176 forming a part of a magnetic path is arranged between the housing 174 and the solenoid 153. Therefore, the solenoid 15
The magnetic flux generated by 3 forms a magnetic path that penetrates the yoke 177 and the frame 176 as shown by a broken line in FIG.

Although the solenoid 153 of this embodiment is slightly different from the cylindrical shape of the first embodiment and is asymmetric at the left and right of the figure, its function is almost the same. b) Next, the operation and effect of the differential pressure control valve 151 of this embodiment will be described. In the differential pressure control valve 151 of the present embodiment, a downstream orifice 166 and a downstream orifice 166 are provided on the downstream side (master cylinder side).
169 are provided.

Therefore, for example, the TRC, VSC,
In the case of using a function such as PAB, when the brake pedal 43 is released, the differential pressure control valve 151 is used as a relief function of the pump upstream pressure (a function of releasing high pressure). Instead of immediately relieving to atmospheric pressure (master cylinder pressure), a slight back pressure is applied by the downstream orifices 166,169.

As a result, it is possible to suppress the occurrence of aeration that is likely to occur when the brake fluid changes from a high pressure to a low pressure, so that the braking performance can be reliably maintained. In this embodiment, since the plunger 152 and the control piston 154 are integrated, the control piston 154 does not easily vibrate when the high-pressure wheel cylinder pressure is relieved. Therefore, also from this point, there is an advantage that aeration can be prevented.

(Embodiment 10) Next, Embodiment 10 will be described, but the description of the same parts as in Embodiment 9 will be omitted or simplified. In the present embodiment, on the downstream side of the differential pressure control valve,
A one-way orifice provided with an auxiliary valve element is disposed as a pressure loss adding mechanism for adding a pressure loss.

As shown in FIG. 19, the differential pressure control valve 181 of this embodiment has a groove-shaped notch orifice 186 in a downstream communication passage 184 that communicates the hollow portion 183 of the guide 182 with the master cylinder. A one-way orifice 189 composed of a spherical auxiliary valve element 187 and an auxiliary spring 188 is provided.

The notch orifice 186 is normally open,
The auxiliary valve element 187 is always urged by the auxiliary spring 188 in the valve closing direction (arrow A). This auxiliary valve element 187
When the differential pressure (large on the wheel cylinder side) increases, the valve moves in the direction of arrow B to open the downstream communication passage 184.

When the pressure difference between the wheel cylinder side and the master cylinder side is large, the one-way orifice 189 is used to release the auxiliary valve element 1 when the brake pedal 43 is released.
Since 87 moves in the direction A in the figure to open the flow path greatly, the flow rate of the brake fluid can be ensured. Thus, a so-called drag feeling (a phenomenon in which the braking force does not become very weak even when the brake pedal 43 is released) can be prevented.

On the other hand, when the differential pressure is small,
87 does not move due to the urging force of the auxiliary spring 188,
It functions as a normal orifice, and can prevent aeration from occurring as in the ninth embodiment. In addition, since the amount of movement of the auxiliary valve element 187 (accordingly, its opening degree) varies depending on the magnitude of the differential pressure, in the case of a differential pressure in which the auxiliary valve element 187 moves slightly, an orifice corresponding to the differential pressure is used. It has the function of

In this embodiment, the one-way orifice 18
9, the inner diameter of the hollow portion 183 is reduced. (Embodiment 11) Next, Embodiment 11 will be described.
The description of the same parts as in the ninth embodiment is omitted or simplified.

In the present embodiment, the control piston
A control sleeve provided with an orifice is disposed as a pressure loss adding mechanism for adding a pressure loss. As shown in FIG. 20, in the differential pressure control valve 191 of the present embodiment, a cylindrical control sleeve 193 is integrally fixed to the outer periphery on the distal end side of the control piston 192, and the control sleeve 193 It covers the periphery of the middle diameter portion 192 a of the piston 192 and the spring 194. Further, a part of the tip of the control sleeve 193 is cut out in a strip shape, and a plurality of notches 196 are provided.

On the other hand, an annular projection 198 is provided on the upper surface of the valve seat 197 so as to cover the outer periphery of the tip of the control sleeve 193. The diameter of each member is set such that there is a slight gap between the inner peripheral surface of the annular convex portion 198 and the outer peripheral surface of the control sleeve 193.

Therefore, when the control piston 192 is raised, the main communication passage 201 and the downstream communication passage 202 are secured through the notch 196 of the control sleeve 193 so that a sufficient flow rate of the brake fluid can be secured. In addition, the flow path is open. On the other hand, when the control piston 192 is lowered, the inner peripheral surface of the annular projection 198 and the control sleeve 193
Since the gap with the outer peripheral surface of the
As in the ninth embodiment, a back pressure can be applied downstream of the differential pressure control valve 191. Thereby, the occurrence of aeration can be prevented.

In particular, in this embodiment, the brake pedal 43
Is returned, the control piston 192 rises and the flow rate of the brake fluid can be ensured, so that there is an advantage that the drag phenomenon is small and the responsiveness is good. In the present embodiment, the downstream orifice of the downstream communication passage unlike the ninth embodiment is not provided.

(Embodiment 12) Next, Embodiment 12 will be described, but the description of the same parts as in Embodiment 9 will be omitted or simplified. In this embodiment, a separate control sleeve or the like is disposed on the tip side of the control piston as a pressure loss applying mechanism for applying a pressure loss.

As shown in FIG. 21, the differential pressure control valve 211 of this embodiment has a cylindrical control sleeve 21 separate from the control piston 212 on the outer periphery of the control piston 212 on the tip side.
3 are slidably arranged. This control sleeve 2
13 is urged by a spring (auxiliary spring) 214 in the valve closing direction (downward in the figure). In addition, control sleeve 2
13 is provided with a cutout 216 that is partially cut out and functions as an orifice.

A stopper 217 is provided between the control sleeve 213 and the middle diameter portion 212a of the control piston 212. The stopper 217 is urged upward in the drawing by a spring (return spring) 218,
It is seated on the step portion 212b, and regulates the downward movement of the control sleeve 213.

On the other hand, on the upper surface of the valve seat 215, a spring 218 is provided.
An annular protrusion 219 is provided between the control sleeve 213 and the tip of the control sleeve 213. The outer periphery of the convex portion 219 is inclined, and the lower end of the control sleeve 213 is seated on this outer periphery. In the present embodiment, the solenoid 22
When power is supplied to the control valve 1, the control piston 212 descends.
At this time, the control sleeve 2 is pressed by the urging force of the spring 214.
13 also falls. Then, just before the control piston 212 is closed, the tip of the control sleeve 213 is seated on the outer periphery of the convex portion 219, and the orifice function is exhibited by the cutout portion 216. Thus, a back pressure can be applied downstream of the differential pressure control valve 211, so that aeration can be prevented.

Before the valve closing of the control piston 212, the tip of the control piston 212 is seated on the outer periphery of the convex portion 219,
The reason that the control piston 212 does not close is that the control piston 2
This is because the orifice function in the cutout portion 216 is ensured at the time of the pressure adjustment control in step S12.

On the other hand, when the solenoid 221 is de-energized, the control piston 212 and the control sleeve 213 rise by the urging force of the spring 218, so that the brake fluid flow path is sufficiently opened and the flow rate is secured. Function is lost. Thus, when the brake pedal 43 is returned, the sense of dragging of the brake is eliminated, and the responsiveness can be improved.

In this embodiment, the downstream orifice of the downstream communication passage is not provided unlike the ninth embodiment. Embodiment 13 Next, Embodiment 13 will be described.
The description of the same parts as in the ninth embodiment is omitted or simplified.

In this embodiment, a lateral force influence reduction mechanism for reducing the influence of the lateral force (side force) due to the magnetic force of the solenoid is provided. a) As shown in FIG. 22 (hatching omitted), in the differential pressure control valve 231 of the present embodiment, a concave portion (magnetic path escape portion) 233 for reducing the outer diameter of the plunger 232 is provided above the plunger 232. , Provided over the entire circumference. Further, recess 2
A protrusion 236 slidably supported by the sleeve 234 is provided above the plunger 232 over the entire circumference of the plunger 232. The position at which the convex portion 236 is formed depends on the solenoid 23
7 is a region where there is almost no magnetic flux generated, that is, outside the magnetic path. That is, the magnetic path by the magnetic flux generated by the solenoid 237 is located below the concave portion 233 as shown in the figure.

B) Next, the operation and effect of this embodiment will be described. A sleeve 23 is provided between the plunger 232 and a location where the magnetic flux is generated (the solenoid 237 and the yoke 238).
Due to the presence of 4, there is a distance (side gap) between the member generating the magnetic flux and the member receiving the urging force due to the magnetic flux. When a magnetic flux is generated, the plunger 232 receives not only the pressing force in the valve closing direction but also a biasing force in the lateral direction (lateral force = side force). However,
This lateral force is not always stable when the side gap exists, and therefore, when the current applied to the solenoid 237 increases or decreases, the lateral force varies between the upstream side and the downstream side of the differential pressure control valve 231. Sometimes there is no fixed pressure difference. That is, hysteresis occurs.

Therefore, in this embodiment, in order to reduce the influence of the lateral force due to the magnetic force of the solenoid 237, which is the cause of the hysteresis, the convex portion 236 of the plunger 232 is provided outside the magnetic path. The plunger 232 is supported by the sleeve 234 so as to slide.

Thus, as shown in FIG. 23, when a predetermined current is applied to the solenoid 232, the determined differential pressure Δ
P can be uniquely set. Specifically, for example, if the current value is A, the differential pressure set by the differential pressure control valve 231 can be set to {PA; PB.

Although not described in the ninth embodiment,
As shown in FIG. 18, an annular concave portion 152a is provided above the plunger 152, and a convex portion 152b similar to that of the present embodiment is provided above the concave portion 152a outside the magnetic path. The convex portion 152b also has a function of reducing the influence of the lateral force, as in the present embodiment.

(Embodiment 14) Embodiment 14 will now be described, but the description of the same parts as in Embodiment 9 will be omitted or simplified. In this embodiment, similarly to the thirteenth embodiment,
A lateral force influence reduction mechanism is provided to reduce the influence of the lateral force (side force) due to the magnetic force of the solenoid.

As shown in FIG. 24, the differential pressure control valve 241 of this embodiment has a plunger 2 above the plunger 242.
A notch 243 for reducing the outer diameter of 42 is provided over the entire circumference. Further, a non-magnetic ring 246 slidably supported by the sleeve 244 is provided at the lower end of the notch 243.
Is fitted outside.

In the case of this embodiment, the plunger 242
Since the non-magnetic ring 246 is positioned in the radial direction, the influence of the lateral force due to the magnetic force of the solenoid 247 can be reduced. As a result, it is possible to prevent the occurrence of hysteresis when the current applied to the solenoid 247 is increased or decreased, and it is possible to realize the preferable characteristics as shown in FIG.

(Embodiment 15) Next, Embodiment 15 will be described. The description of the same parts as in Embodiment 9 will be omitted or simplified. In this embodiment, as in the above-described embodiments 13 and 14, the lateral force (side force) caused by the magnetic force of the solenoid is used.
A lateral force effect reduction mechanism is provided to reduce the effect of the force.

As shown in FIG. 25, in the differential pressure control valve 251 of this embodiment, the relief diameter 253 is formed by decreasing the outer diameter of the plunger 252 upward. The escape portion 253 has a function of reliably providing a clearance between the sleeve 255 and an inclination caused by a clearance in the support portion 257 described later, and stabilizing the movement of the plunger 252.

Further, a plurality of grooves 256 through which brake fluid can pass in the axial direction are formed on the outer periphery of the valve body 254 integrally connected to the plunger 252. In addition, each groove 256
A support portion 257 projecting in the outer peripheral direction of the valve body 254 is formed along the axial direction.
Is supported by the guide 258 and slides, so that the valve body 254 can move in the vertical direction.

That is, in this embodiment, since the support portion 257 of the valve body 254 is slidably supported by the guide 258, the influence of the lateral force on the magnetic force of the solenoid 259 can be reduced, and the above-described hysteresis can be prevented. Can be eliminated. Further, since the supporting portion 257 of the valve element 254 is slidably supported by the guide 258, the generation of vibration near the seating position of the valve element 254 is prevented, similarly to the ninth embodiment, and aeration is achieved. Can be suppressed.

(Embodiment 16) Next, Embodiment 16 will be described, but the description of the same parts as in Embodiment 9 will be omitted or simplified. In this embodiment, the shape of the tip of the needle is devised so as to reduce the pressure loss when the valve is opened.

Conventionally, as shown in FIG. 26A, the tip of the needle has an acute angle, which causes a pressure loss when the valve is opened. Therefore, in this embodiment,
As shown in FIG. 26 (b), the tip of the needle tip 262 of the valve body 261 is flattened (perpendicular to the axial direction).
It is cut. Thereby, pressure loss at the time of valve opening can be reduced.

In another embodiment, as shown in FIG. 26 (c), the shape of the needle tip 272 of the valve body 271 is such that the tip is an obtuse cone. Thereby, pressure loss at the time of valve opening can be reduced. Further, in another embodiment, FIG.
6 (d), the needle tip 28 of the valve body 281
As the shape of No. 2, the tip is a smooth curve (substantially spherical) shape. Thereby, pressure loss at the time of valve opening can be reduced.

(Embodiment 17) Next, Embodiment 17 will be described. The present embodiment shows a method for inspecting a differential pressure control valve. Here, the differential pressure control valve of the ninth embodiment will be described as an example of a differential pressure control valve to be inspected.

As shown in FIG. 27, the inspection unit 30
In the differential pressure control valve before assembly, the plunger 152, the control piston 154, the spring 158, the valve seat 1
57, a guide 156 and the like are assembled. The inspection reference coil unit 302 is placed on the inspection unit 301 from the plunger 152 side (the upper side in the figure). The inspection reference coil unit 302 is a solenoid 1
53, a yoke 177, a frame 176, a sleeve 160 and the like for generating magnetic force.

Then, as shown in FIG. 28, the inspection unit 301 and the inspection reference coil unit 302 are combined, the power source 303 is connected to the solenoid 153, and the power source
03 and the ammeter 304 are arranged directly. On the other hand, the measuring device 306 is arranged in the main communication hole 163 on the master cylinder side (but without the filter 171). This measuring device 30
Reference numeral 6 denotes a shape in which the rod 308 is extended from the tip of the conical portion 307, and the upper end of the rod 308 is in contact with the lower end of the needle tip 165. Also, the measuring device 306
A load cell (not shown) is disposed below the load cell for measuring the pressing force applied to the measuring device 306, that is, the pressing force applied from the needle tip 165 to the rod 308.

In this configuration, for example, the solenoid 15
The load applied in this case is changed (the pressing force of the control piston 154 by the magnetic force of the solenoid 153).
From the relationship between the current and the load, it can be determined whether or not desired solenoid attraction force characteristics are obtained.

Embodiment 18 Next, Embodiment 18 will be described. This embodiment shows a method of adjusting a differential pressure control valve using an adjustment shim. Here, the differential pressure control valve of the ninth embodiment will be described as an example of a differential pressure control valve to be inspected.

For example, it is assumed that the measurement method (attraction force characteristic of the solenoid 153) indicated by the solid line in FIG. 29 is obtained by the inspection method described in the seventeenth embodiment. In this case, the target suction force characteristic is indicated by a broken line in FIG. The control piston 154 includes a spring (return spring) 158.
Urged in the valve opening direction by the solenoid 15
3 is zero, the load F is
An offset load of 8 (however, because the direction is in the opposite direction,-).

Therefore, shim adjustment is performed to change the measured suction force characteristic of the solid line to the target suction force characteristic of the broken line. In the shim adjustment, as shown in FIG. 30, the offset shim 401 is adjusted by displacing (arranging) the adjustment shim 401 between the spring 158 and the control piston 154. For example, by offsetting the adjustment shim 401, the offset load is reduced as shown in FIG.
As shown in FIG. 9, it is translated downward by Δt. As a result, the solid line attractive force characteristic can be changed to the broken line attractive force characteristic.

Since the offset load can be changed by changing the thickness of the adjustment shim, the suction force characteristic can be changed by moving the suction force characteristic to an arbitrary position in parallel.
The load F (or FA) corresponds to the differential pressure △ P (or △ PA) × the cross-sectional area S of the orifice 162 when the actual differential pressure control valve is used.

(Embodiment 19) Next, Embodiment 19 will be described. This embodiment shows another mode of the differential pressure control valve adjusting method using the adjustment shim shown in the eighteenth embodiment. Here, the differential pressure control valve to be inspected is the same as the ninth embodiment. A substantially similar differential pressure control valve will be described as an example.

In this case, the effect of the adjustment is the same as that of the eighteenth embodiment, and the offset load is adjusted by changing the set length of the return spring.
This embodiment is different from the eighteenth embodiment in that the adjustment is made possible in the post-process of assembling the valve seat and the sleeve after press fitting and welding.

That is, in the eighteenth embodiment, the adjustment shim is applied between the return spring and the stepped portion of the body valve (the receiving surface of the spring).
It is necessary to select an adjustment shim before assembling the valve seat or the sleeve, and it is not possible to cover the characteristic change due to the subsequent assembling.

Therefore, in this embodiment, as shown in FIGS. 31 and 32, the adjustment shim 501 is inserted between the return spring 503 and the valve seat 505 through a hole (insertion hole) 509 provided in the guide 507. It can be inserted from outside. The adjustment shim 501 has a front end side (left side in both figures) branched into two and a rear end side vertical (FIG. 31).
Is provided with a substantially U-shaped notch 513 so that the needle tip 511 of the control piston 510 can enter at the branching point. As a result, the lower end of the return spring 503 is
01 is received in contact with the upper surface of the light emitting device 01.

That is, in the present embodiment, in the post-process of assembling after the press-fitting and welding of the valve seat 505 and the sleeve 515, that is, in the final assembling process, it is possible to adjust the characteristics as the final valve configuration, and to achieve more accurate Good characteristic adjustment becomes possible. It is more preferable that the adjustment shim 501 be provided with a lock mechanism to prevent the adjustment shim 501 from coming off. This locking mechanism is shown in FIGS. 31 and 32.
The engaging portion 517 on the rear end side of the adjustment shim 501 and the guide 50
7 is a locking groove 519 in the insertion hole 509 of FIG.

(Embodiment 20) Next, Embodiment 20 will be described. This embodiment corresponds to the eighteenth and nineteenth embodiments.
This shows another mode of the offset load adjustment method for the differential pressure control valve similar to that described above. Here, as the differential pressure control valve to be inspected, a differential pressure control valve substantially similar to that of the ninth embodiment will be described as an example.

In this case, the effect of the adjustment is the same as that of the eighteenth embodiment and the nineteenth embodiment. The offset load is adjusted by changing the set length of the return spring. The characteristic adjustment in the post-assembly step similar to that in Example 19 is performed by means different from that in Example 19.

That is, in the eighteenth and nineteenth embodiments, the set load of the return spring is changed by the shim adjustment. However, in the present embodiment, the combination of the ratchet mechanism is changed to change the step load gradually. This is to change the set load of the return spring.

More specifically, as shown in FIG. 33, a disc-shaped ratchet 605 is arranged between the return spring 601 and the valve seat 603. This ratchet 605 has
As shown in FIG. 34, a spline-shaped outer peripheral tooth portion 605a and a ratchet-shaped lower tooth portion 605b are provided, and a claw portion 607 is provided on the valve seat 603 side facing the lower tooth portion 605b.
Is provided.

The combination of the engagement between the ratchet 605 and the claw portion 607 on the valve seat 603 side, that is, one of the combinations shown in FIG. The guide hole 611 provided in the guide 609 shown is hooked to the outer peripheral tooth portion 605a of the ratchet 605 by a driver or the like, and rotated.
It can be changed.

As a result, the ratchet 605 and the valve seat 60
The position of the return spring 601 can be adjusted as a result. Therefore, in the present embodiment, similarly to the nineteenth embodiment, in the final assembly process, the characteristics of the final valve configuration can be adjusted.
It is possible to perform more accurate characteristic adjustment. Further, there is an advantage that the configuration for adjustment is simple.

Embodiment 21 Next, Embodiment 21 will be described. This embodiment shows a method of adjusting a differential pressure control valve using an adjustment plate. Here, the differential pressure control valve of the ninth embodiment will be described as an example of a differential pressure control valve to be inspected.

For example, it is assumed that the measurement result (attraction force characteristic) shown by the solid line in FIG. 35 is obtained by the inspection method described in the seventeenth embodiment. In this case, the target suction force characteristic is indicated by a broken line in FIG. Therefore, in order to change the measured attractive force characteristic of the solid line to the target attractive force characteristic of the broken line, the magnetic aperture is adjusted.

The adjustment of the magnetic aperture means that, as shown in FIG. 30, the plurality of plate-shaped adjustment plates 402 constituting the frame 176 are exchanged to change the shape of the magnetic aperture section 403.
Thereby, the state of the magnetic path, that is, the magnetic flux passing through the frame 176 is adjusted to adjust the gradient of the attraction force characteristic.

It is to be noted that a ring-shaped adjusting plate 402 can be employed as the adjusting plate 402. By preparing and using a plurality of adjusting plates 402 in which only the portion constituting the magnetic aperture portion 403 is cut out, the selected adjusting plate 402 is used. , A frame 176. For example, when the adjustment plate 402 is changed to increase the size of the magnetic aperture 403 (particularly, the cross-sectional area in the vertical direction in the drawing), the magnetic path becomes smaller. As a result, even if the applied current is increased, the load hardly increases. That is, when the size of the magnetic throttle unit 403 is increased, the gradient of the attraction force characteristic is reduced.

Therefore, since the offset load is not changed, if the size of the magnetic throttle unit 403 is increased, as shown in FIG. 35, the gradient of the attraction force characteristic is reduced by Δα. As a result, the solid line attractive force characteristic can be changed to the broken line attractive force characteristic. Embodiment 22 Next, Embodiment 22 will be described.

The present embodiment shows a method of adjusting a differential pressure control valve by adjusting an air gap between a mover and a stator on a magnetic circuit. The differential pressure control valve according to the ninth embodiment will be described as an example. For example, it is assumed that the measurement method (attraction force characteristic) indicated by the solid line in FIG. 35 is obtained by the inspection method described in the seventeenth embodiment. in this case,
The target suction force characteristic is shown by a broken line in FIG.

Therefore, in the present embodiment, air gap adjustment is performed to change the measured suction force characteristic of the solid line to the target suction force characteristic of the broken line. This air gap adjustment is, as shown in FIG. 30, by adjusting the amount of press-fit of the valve seat 157 into the guide 156, so that the air gap between the mover (plunger 152) and the stator (guide 156) constituting the magnetic circuit is adjusted. Change the air gap of the
Thereby, the state of the magnetic path, that is, the magnetic flux passing through the air gap is adjusted to adjust the gradient of the attraction force characteristic.

For example, if the press-fit amount of the valve seat 157 is changed (increased) to increase the air gap when the valve is closed,
The generated magnetic force decreases. As a result, even if the applied current is increased, the load hardly increases. That is, when the air gap is increased, the gradient of the suction force characteristic is reduced.

Therefore, since the offset load is not changed, if the air gap is increased, as shown in FIG. 35, the gradient of the suction force characteristic decreases by Δα. As a result, the solid line attractive force characteristic can be changed to the broken line attractive force characteristic. Contrary to the above, when the air gap is reduced, the gradient of the suction force characteristic increases.

Embodiment 23 Next, Embodiment 23 will be described. In this embodiment, the offset load change by adjusting the set load of the return spring shown in the eighteenth embodiment and the suction force characteristic change by the air gap adjustment shown in the twenty-second embodiment are adjusted by adjusting the press-fit amount of the valve seat. The method of realizing at the same time is shown.

The difference between the structure and the effect of the twenty-second embodiment is that, as shown in FIG.
01 is changed to the guide 705 instead of the valve seat 703. Thus, by adjusting the press-fit amount of the valve seat 703 (the seat press-fit amount), the movable element (plunger 70) is adjusted.
7) and the air gap between the stator (guide 705) and the return spring 701 at the same time.
Can be changed (the valve-closing side at the time of adjustment).

Therefore, even in a region where the suction force changes little with respect to the air gap (the actual use region in FIG. 1) as shown in FIG.
The adjustment gain can be maintained. That is, in the actual use region of FIG. 1, even if the air gap is slightly changed, the change in the suction force is small and the effect of the adjustment is difficult to obtain, but in the present embodiment, the adjustment is accompanied by the change of the offset load. Adjustment effect is always ensured.

Further, in this embodiment, the configuration of the valve seat 703 can be simplified, and the hole drilling of the check valve 709 can be performed by the guide 7.
Since it is possible to concentrate on the 05 side, there is room in space, which is advantageous in manufacturing. (Embodiment 24) Next, Embodiment 24 will be described.

This embodiment shows a method of adjusting a differential pressure control valve using an adjustment shim and an adjustment plate. In this embodiment, the differential pressure control valve of the ninth embodiment is used as a differential pressure control valve to be inspected. Take for example. In the present embodiment, the adjustments of the eighteenth embodiment and the twenty-first embodiment are both performed.

For example, it is assumed that a measurement result (attraction force characteristic) indicated by a solid line in FIG. 37 is obtained by the inspection method described in the seventeenth embodiment. In this case, the target suction force characteristic is indicated by a broken line in FIG. Therefore, in order to change the measured attractive force characteristic of the solid line to the target attractive force characteristic of the broken line, the magnetic aperture adjustment and the shim adjustment are performed.

First, the gradient of the solid line attractive force characteristic is changed by adjusting the magnetic aperture to obtain the attractive force characteristic indicated by the one-dot chain line. Next, by the shim adjustment, the suction force characteristic indicated by the one-dot chain line is moved in parallel to obtain the suction force characteristic indicated by the broken line in the figure.

Thus, even if the suction force characteristic of the differential pressure control valve to be measured is greatly different from the target suction force characteristic, the target suction force characteristic can be easily adjusted by the magnetic throttle adjustment and the shim adjustment. It can be. In the adjustment of the magnetic aperture, an example was given in which the gradient of the attraction force characteristic was reduced.However, a reference magnetic aperture was set, and the gradient was reduced by enlarging the magnetic aperture to reduce the magnetic aperture. It can be reduced to increase the slope.

Similarly, with regard to shim adjustment, it is also possible to arrange an adjustment shim serving as a reference, increase the offset load by increasing the thickness of the adjustment shim, and translate the suction force characteristic downward in FIG. On the other hand, by reducing the thickness of the adjustment shim, the offset load can be reduced, and the suction force characteristic can be translated upward in FIG.

It is needless to say that the present invention is not limited to the above-described embodiments, and can be implemented in various modes without departing from the technical scope of the present invention. For example, the differential pressure control valves of the above-described embodiments are the same as those shown in FIGS.
2 can be used for the vehicle brake device.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing a relationship between a suction force and a plunger stroke by comparing the present invention with a conventional example.

FIGS. 2A and 2B show a comparison between the present invention and a conventional example. FIG. 2A is an explanatory diagram showing a relationship between a generated differential pressure and an applied current, and FIG. 2B is an explanatory diagram showing a relationship between a suction force and a plunger stroke. It is.

FIG. 3 is an explanatory diagram illustrating a structure of a differential pressure control valve according to the first embodiment.

FIG. 4 is an explanatory diagram showing an enlarged view of a magnetic short-circuit structure of the differential pressure control valve according to the first embodiment.

FIG. 5 is a schematic configuration diagram illustrating a vehicle brake device using the differential pressure control valve according to the first embodiment.

FIG. 6 is an explanatory diagram illustrating a relationship between a W / C pressure and an M / C pressure according to the first embodiment.

FIG. 7 is an explanatory diagram illustrating a change in magnetic flux in the magnetic short-circuit structure of the differential pressure control valve according to the first embodiment.

FIG. 8 is a flowchart illustrating pressure amplification assist brake control according to the first embodiment.

FIG. 9 is a flowchart illustrating control when the brake booster of the first embodiment fails.

FIG. 10 is a schematic configuration diagram illustrating a vehicle brake device according to a second embodiment.

FIG. 11 is a flowchart illustrating traction control according to the second embodiment.

FIG. 12 is a schematic configuration diagram illustrating a vehicle brake device according to a third embodiment.

FIG. 13 shows W / C pressure and M / C on the rear wheel side according to the third embodiment.
It is explanatory drawing which shows the relationship with pressure.

FIG. 14 is a flowchart showing control of braking force distribution according to the third embodiment.

15A and 15B show another embodiment, in which FIG. 15A is an explanatory view showing a magnetic short-circuit structure of the fourth embodiment, FIG. 15B is an explanatory view showing a magnetic short-circuit structure of the fifth embodiment, and FIG. It is explanatory drawing which shows a magnetic short structure, (d) is explanatory drawing which shows the magnetic short structure of Example 7. FIG.

FIG. 16 is an explanatory view showing a magnetic short-circuit structure according to an eighth embodiment.

FIG. 17 is an explanatory diagram showing a change in magnetic flux in the magnetic short-circuit structure according to the eighth embodiment.

FIG. 18 is an explanatory diagram showing a differential pressure control valve according to a ninth embodiment.

FIG. 19 is an explanatory diagram showing a differential pressure control valve according to a tenth embodiment.

FIG. 20 is an explanatory diagram showing a differential pressure control valve according to an eleventh embodiment.

FIG. 21 is an explanatory view showing a differential pressure control valve according to a twelfth embodiment.

FIG. 22 is an explanatory diagram showing a differential pressure control valve according to a thirteenth embodiment.

FIG. 23 is an explanatory diagram showing characteristics of a target differential pressure control valve.

FIG. 24 is an explanatory diagram showing a differential pressure control valve according to a fourteenth embodiment.

FIG. 25 is an explanatory view showing a differential pressure control valve according to a fifteenth embodiment.

26A and 26B show a needle tip, FIG. 26A is an explanatory view of a conventional needle tip, FIG. 26B is an explanatory view of a needle tip of Embodiment 16, and FIG. 26C is a needle tip of another embodiment. (D) is a needle tip portion of still another embodiment.

FIG. 27 is an explanatory view showing an inspection method of the differential pressure control valve according to the seventeenth embodiment.

FIG. 28 is an explanatory view showing an inspection method of the differential pressure control valve according to the seventeenth embodiment.

FIG. 29 is an explanatory view showing an adjusting method of the differential pressure control valve according to the eighteenth embodiment.

FIG. 30 is an explanatory diagram showing a configuration for changing a suction force characteristic.

FIG. 31 is an explanatory diagram showing a differential pressure control valve according to a nineteenth embodiment.

FIG. 32 is an explanatory diagram showing the vicinity of an adjustment shim used in the differential pressure control valve according to Embodiment 19, as viewed from the control piston side.

FIG. 33 is an explanatory diagram showing a differential pressure control valve according to a twentieth embodiment.

FIG. 34 shows a ratchet mechanism according to a twentieth embodiment;
(A) is a side view showing the ratchet, (b) is a bottom view showing the ratchet, and (c) is an explanatory view showing a state where the ratchet and the valve seat are expanded 360 ° to show an engagement relationship between the ratchet and the valve seat.

FIG. 35 is an explanatory diagram showing an adjusting method of the differential pressure control valve according to the twenty-first embodiment.

FIG. 36 is an explanatory diagram showing a differential pressure control valve according to Embodiment 23.

FIG. 37 is an explanatory diagram showing an adjusting method of the differential pressure control valve according to the embodiment 24.

[Explanation of symbols]

1,71,72,91,101,111,121,13
1,141,151,181,191,211,23
1,245,251 ... Differential pressure control valve 2,144,153,221,237,247,259
... Solenoids 3,103,113,123,133,142,15
2, 232, 242, 252, 707 ... plunger 4, 102, 122, 132, 160, 234, 24
4,515 ... Sleeve 6,106,117,134,154,192,21
2,254,261,271,281,510 ... control piston 7,105,115,126,135,146,15
6, 182, 258, 507, 609, 705: Guide 8, 145, 177, 238: Yoke 21, 104, 116, 125: Projected portion 22, 108, 114 (at the magnetic short portion) Recesses 31, 41, 92 ... master cylinders 32, 55, 56, 57, 58, 93, 94 ... wheel cylinders 36, 77, 79 ... pumps

 ──────────────────────────────────────────────────の Continuing from the front page (72) Takahiro Naganuma 1-1-1, Showa-cho, Kariya-shi, Aichi Prefecture Inside Denso Corporation (72) Inventor Hiroyuki Shinkai 1-1-1, Showa-cho, Kariya-shi, Aichi Prefecture Denso Corporation Inside

Claims (32)

[Claims] 1. A differential pressure control valve arranged in a brake fluid line for adjusting a differential pressure of a brake fluid pressure, wherein the differential pressure control valve penetrates a magnetic flux generated by a solenoid and moves by a magnetic force of the solenoid. And a stator arranged in the moving direction of the mover and through which the magnetic flux by the solenoid penetrates, and the magnetic flux in the moving direction of the mover and the stator accompanying the movement of the mover. A differential pressure control valve characterized by having a magnetic short-circuit structure for suppressing a change in amount. 2. The magnetic short-circuit structure according to claim 1, wherein a magnetic flux in a direction different from the moving direction changes between the mover and the stator as the mover moves. The differential pressure control valve according to claim 1, wherein: 3. The magnetic short structure is a concave or convex portion provided on the mover and the stator, which can be fitted to each other, and the fitted state changes when the mover moves. The differential pressure control valve according to claim 1, wherein: 4. The differential pressure control valve according to claim 3, wherein the concave portion and the convex portion have a surface parallel to the moving direction. 5. The differential pressure control valve according to claim 3, wherein the concave portion and the convex portion have surfaces oblique to the moving direction. 6. The apparatus according to claim 3, wherein even when the differential pressure control valve is off, the mover and the stator have a region overlapping in a direction perpendicular to a moving direction of the mover. 6. The differential pressure control valve according to any one of claims 5 to 5. 7. The magnetic short-circuit structure according to claim 1, wherein when the mover moves, the amount of magnetic flux between the yoke of the solenoid and the mover changes. The differential pressure control valve as described. 8. The differential pressure control valve according to claim 1, wherein the differential pressure control valve is driven by current control according to a magnitude of a current supplied to the solenoid. . 9. The differential pressure control valve according to claim 1, wherein the differential pressure control valve is driven by on-off duty control of a current supplied to the solenoid. 10. The differential pressure control valve according to claim 1, wherein a pressure loss adding mechanism for adding a pressure loss is provided downstream of the differential pressure control valve. 11. The differential pressure control valve according to claim 10, wherein the pressure loss adding mechanism is an orifice. 12. The differential pressure control valve according to claim 10, wherein the pressure loss adding mechanism is an auxiliary valve body biased by biasing means. 13. The differential pressure control according to claim 1, further comprising a vibration suppressing mechanism for suppressing vibration in the vicinity of a seating position of a valve body operated by the operation of the mover. valve. 14. The differential pressure control valve according to claim 13, wherein the vibration suppressing mechanism is configured to connect the mover and the valve body integrally. 15. The differential pressure according to claim 13, wherein the vibration suppressing mechanism is configured to slidably support the valve body by a tubular body into which the valve body is fitted. Control valve. 16. The difference according to claim 1, further comprising a lateral force influence reduction mechanism for reducing an influence of a lateral urging force on the mover due to a magnetic force of the solenoid. Pressure control valve. 17. The apparatus according to claim 16, wherein the lateral force effect reducing mechanism is configured to slidably support the mover outside a magnetic path of a magnetic flux generated by the solenoid. Differential pressure control valve. 18. The apparatus according to claim 16, wherein the lateral force effect reducing mechanism has a configuration in which a non-magnetic member is arranged around the mover, and the non-magnetic member is slidably supported.
2. The differential pressure control valve according to 1. 19. The valve according to claim 1, wherein a pressure loss reducing structure for reducing a pressure loss at the time of valve opening is provided at a tip end of a needle of a valve body operated by the operation of the mover. The differential pressure control valve as described. 20. The pressure loss reducing structure according to claim 19, wherein the needle tip has an obtuse angle.
2. The differential pressure control valve according to 1. 21. The differential pressure control valve according to claim 19, wherein the pressure loss reducing structure is configured to cut a needle tip portion flat. 22. The differential pressure control valve according to claim 19, wherein the pressure loss reducing structure is configured to smoothly curve a tip portion of the needle. 23. The method for inspecting a differential pressure control valve according to claim 1, wherein the movable element, a valve body operated by the operation of the movable element,
A step of arranging a solenoid and a sleeve used for inspection on the outer periphery of the mover, for a basic structure of a differential pressure control valve including a spring for urging the valve body and a guide for the valve body. A step of arranging, at the tip of the valve element, a measuring means for measuring the pressing force of the valve element by the magnetic force of the inspection solenoid; energizing the inspection solenoid, And a step of measuring by the measuring means. 24. The method for adjusting a differential pressure control valve according to claim 1, wherein a current supplied to the solenoid and a pressing force of the valve element by a magnetic force of the solenoid are set to a predetermined value. To satisfy the relationship
A method for adjusting a differential pressure control valve, comprising adjusting an offset load of a spring for urging the valve body in a direction opposite to the pressing force. 25. The method for adjusting a differential pressure control valve according to claim 1, wherein a current supplied to the solenoid and a pressing force of the valve element by a magnetic force of the solenoid are set to a predetermined value. To satisfy the relationship
A method for adjusting a differential pressure control valve, comprising adjusting a gradient of the solenoid suction force characteristic. 26. The method for adjusting a differential pressure control valve according to claim 1, wherein a current applied to the solenoid and a pressing force of the valve element by a magnetic force of the solenoid are set to a predetermined value. To satisfy the relationship
A method for adjusting a differential pressure control valve, comprising adjusting an offset load of a spring for urging the valve body in a direction opposite to the pressing force, and adjusting a gradient of the solenoid attraction force characteristic. 27. Adjustment of the offset load of the spring,
The method for adjusting a differential pressure control valve according to claim 24, wherein the adjustment is performed by changing a thickness of an adjustment shim that changes an offset length of the spring. 28. Adjustment of the offset load of the spring,
27. The adjusting method of the differential pressure control valve according to claim 24, wherein the adjusting is performed by changing an engagement combination position of a ratchet for changing an offset length of the spring. 29. The method according to claim 25, wherein the gradient of the solenoid attraction force characteristic is adjusted by changing an adjustment plate for changing a state of a magnetic path.
3. The method for adjusting a differential pressure control valve according to 1. 30. The method according to claim 25, wherein the gradient of the solenoid attraction force characteristic is adjusted by changing an amount of an air gap between the mover and the stator to change a state of a magnetic path. Or the adjusting method of the differential pressure control valve according to 26. 31. A brake fluid pressure generating means for generating a brake fluid pressure at the time of vehicle braking, a wheel braking force generating means for receiving a brake fluid pressure from the brake fluid pressure generating means and generating a wheel braking force, A brake fluid moving means for moving the brake fluid from a brake fluid pressure generating means side to the wheel braking force generating means side, wherein the brake fluid pressure generating means and the wheel braking force generating means side In the pipeline between and, the differential pressure control valve according to any one of claims 1 to 22 is disposed, and when the brake fluid moving means is operated, the differential pressure control valve is divided by the differential pressure control valve. A brake device for a vehicle, wherein a brake fluid pressure on a wheel braking force generating means side can be increased. 32. A brake fluid pressure generating means for generating a brake fluid pressure at the time of vehicle braking, and a wheel braking force generating means for receiving a brake fluid pressure from the brake fluid pressure generating means and generating a wheel braking force. A vehicle brake device comprising: a differential pressure control valve according to any one of Claims 1 to 22, disposed in a pipeline between the brake fluid pressure generating means and the wheel braking force generating means; A brake device for a vehicle, wherein the brake fluid pressure on the side of the wheel braking force generating means divided by the differential pressure control valve can be reduced.