JPH11311349A - Hydraulic relief valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent vibration of a valve element without requiring high degree processing precision. SOLUTION: This hydraulic relief valve 1 provides a guide body 21 on a protruded part 24 of a valve seat member 19 on which a poppet valve element 20 is seated free to slide. Additionally, a shaft part 30 of the poppet valve element 20 is fitted in a sliding hole 35 of the guide goby 21 and integrated with it. In this constitution, the poppet valve element 20 is free to be separated and seated by the guide body 21 and held on a side to approach the valve seat member 19.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic relief valve for controlling water pressure by using water as a working fluid.

[0002]

2. Description of the Related Art As a conventional hydraulic relief valve, there is a balanced piston type as shown in FIG. The hydraulic pressure relief valve 51 of FIG. 6 passes the operating water of the high pressure port 53 from the intermediate chamber A through the valve member 52 of the main valve PB to the poppet valve element 5.
4 Then, when the working water becomes equal to or higher than the predetermined pressure, the poppet valve element 54 separates from the valve seat member 55 and opens the pilot valve CB. Then, the valve member 52 of the main valve PB is caused to flow out from the space between the poppet valve element 54 and the valve seat member 55 to the low-pressure port 57 through the passage 56 so that the valve member 52 of the main valve PB is opposed to the valve spring 58 by the water pressure on the high-pressure port side. Then, the main valve PB is opened. This hydraulic relief valve 5
1 adopts a structure in which a shaft portion 60 extending to the upper end of the back pressure chamber B is slidably guided by an annular member 61 in order to prevent the poppet valve body 54 from being vibrated by hydraulic water jetted into the back pressure chamber B. ing.

[0003]

In the conventional hydraulic relief valve, it is necessary to form a gap between the shaft portion 60 of the poppet valve body 54 and the annular member 61 to allow sliding. Accordingly, when the shaft portion 60 of the poppet valve element 21 is guided by the annular member 61 separated from the valve seat member 55, the vibration width due to the gap becomes large on the side where the poppet valve element 54 sits on the valve seat member 55. With this configuration, when the pilot valve CB is opened, the poppet valve element 54 that receives the operating water ejected from the valve seat member is greatly vibrated, and the tip of the poppet valve element 54 comes into contact with the valve seat member 55 and Abnormal noise may occur. In order to prevent this vibration, it is necessary to manage the gap between the shaft portion 60 of the poppet valve element 54 and the annular member 61, and these members 60 and 61 also require high processing accuracy, which leads to an increase in manufacturing cost. .

An object of the present invention is to prevent vibration of a valve body without requiring high processing accuracy.

[0005]

In the hydraulic relief valve according to the present invention, the valve body seated on the valve seat member is slidably held on the valve seat member by a guide body.

The guide body is slidably provided on a cylindrical projection of the valve seat member. The projection is preferably formed coaxially with the valve seat on which the valve element is seated (claim 3).

[0007] The guide body is formed in a bottomed cylindrical shape, and a circular convex portion is formed in the valve seat member. Then, the cylindrical portion of the guide body is slidably fitted into the convex portion, and the valve body is integrally held by the sliding hole of the bottom plate. In addition, a communication hole communicating the guide body and the low-pressure port is formed in the guide body.

The communication hole may be formed in a bottom plate of the guide body (Claim 5), or may be formed from the bottom plate of the guide body to the cylindrical portion (Claim 6). The communication hole is
It is preferable to form a plurality at equal intervals around the bottom sliding hole.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A hydraulic relief valve according to an embodiment of the present invention will be described below with reference to the drawings.

A hydraulic relief valve 1 shown in FIG. 1 includes a main valve PB for controlling the hydraulic pressure (flow rate) of working water from a high pressure passage to a low pressure passage (not shown), and a pilot valve CB for adjusting the opening and closing of the main valve PB. A high-precision processing accuracy by holding the poppet valve element 20 of the main valve CB slidably on the valve seat member 19 by the guide element 22. No, valve seat member 1
This prevents vibration of the poppet valve body 20 due to the hydraulic water spouted from the nozzle 9.

The valve main body 2 of the main valve PB has a bottomed valve hole 3 opening at one end, in which a valve seat sheet material 4, a valve member 5, a socket 6, and a valve spring 7 are provided. Is stored. On the outer periphery of the valve body 2, a high-pressure port 8 opening to the bottom 3 a of the valve hole 3 and a low-pressure port 9 opening to the inner periphery of the valve hole 3 are formed. Each of the ports 8, 9 is communicated with each other through the valve hole 3, and is connected to each of the high-pressure passage and the low-pressure passage.

The valve seat 4 in the valve body 2 has a flanged annular shape and is located between the high-pressure port 8 and the low-pressure port 9. Further, a valve seat 11 is formed in the valve seat material 4 at an inner peripheral end protruding toward the low pressure port 9 side. Thus, the operating water from the high pressure port 8 flows out to the low pressure port 9 through the valve seat 4.

The valve member 5 in the valve body 2 is seated on the valve seat 11 from the low pressure port 9 side, and the main valve PB is joined with the valve seat sheet material 4.
Is composed. Inside the valve member 5, a stepped passage 13 including a throttle hole 12 opening into the valve seat material 4 is formed. The stepped passage 13 is enlarged in diameter on the opening side of the valve body 2 and penetrates the valve member 5, and the valve member 5 is pressed against the valve seat 11 by the valve spring 7 stretched in the enlarged diameter hole ( Urging). The valve member 5 is slidably held by the socket 6. Incidentally, the valve member 5 is formed of SUS630 JIS symbol), and a hard layer is formed by a precipitation hardening treatment (heat treatment or the like).

The socket 6 for holding the valve member 5 is formed in a cylindrical shape and slidably holds the valve member 5 on the inner periphery.
The socket 6 is inserted from the opening side of the valve body 2 and extends to the valve seat 4 while forming a gap passage 14 with the inner periphery of the valve hole 3. The distal end side of the socket 6 is enlarged in diameter and fitted into the inner periphery of the valve hole 3 and the outer periphery of the valve seat 4 via a sealing member (such as an O-ring) to position the valve seat 4 in the axial direction. doing. A plurality of through-holes 6a are formed at the tip end of the socket 6 to communicate the valve seat 4 with the low-pressure port 9, and the operating water flows out of the valve seat 4 to the low-pressure port 9 through each through-hole 6a. . Then, the socket 6 is connected to the valve body 1 of the pilot valve CB on the opening side of the valve body 2.
5 is connected. The socket 6 is made of SUS630, and is subjected to hard chrome plating after the precipitation hardening process.

The valve body 15 of the pilot valve CB is formed by screwing two blocks 16 and 17 together with a sealing member (such as an O-ring) interposed therebetween. The block 16 is connected to the opening side of the valve body 2 via the sealing member. It is screw-connected by screwing inside. The valve hole 3 of the valve body 2 is provided inside the valve body 15.
A valve hole 18 penetrating through the blocks 16 and 17 is formed in the valve hole 18, and the valve seat member 19 of the pilot valve CB, the poppet valve body 20, the guide body 21 and the valve spring 2
2 etc. are arranged.

The valve seat member 19 in the valve body 15 is positioned between the socket 6 screwed into the block 16 and the projection 23 of the block 16. Thus, the valve seat member 15 defines an intermediate chamber A and a back pressure chamber B on the valve member 5 side and the block 17 side of the main valve PB. Also, the valve seat member 19
Is formed with a columnar projection 24 projecting toward the back pressure chamber B side with a gap between the inner circumferences of the block 17. Inside the valve seat member 19, a throttle hole 25 opening into the intermediate chamber A,
Valve seat hole 26 whose diameter is enlarged and which opens into back pressure chamber B at the end of convex portion 24
Are continuously formed. At the open end of the valve seat hole 26, a valve seat 27 coaxial with the projection 24 is formed. The valve seat member 19 receives the valve spring 7 on the intermediate chamber A side and the valve spring 7 is stretched. The back pressure chamber B communicates with the low pressure port 9 through a passage 28 and a gap passage 13 formed on the inner periphery of the block 16.

The poppet valve body 20 in the valve body 15 is seated on the valve seat 27 from the back pressure chamber B side, and forms a pilot valve CB with the valve seat member 19. The poppet valve element 20 includes a block 17 from a conical valve portion 29 seated on a valve seat 27.
A shaft portion 30 protruding to the side is formed. The valve body 15 is slidably held by the guide body 21, and a valve spring 22 is stretched between the guide body 21 and the spacer 31.
To be pressed (biased) against the valve seat 27. The spring force of the valve spring 22 rotates the adjustment bolt 32 screwed into the valve hole 18 from the tip of the block 17, and the spacer 3 in the adjustment bolt 32.
It is adjusted by moving back and forth by 1.

As shown in FIG. 2, the guide body 21 has a bottom plate 34 for closing one end of the cylindrical member 33. A sliding hole 35 coaxial with the cylindrical member 33 is formed in the bottom plate 34. Have been. In the bottom plate 33 of the guide body 21, a plurality of communication holes 36 are formed at equal intervals around the sliding hole 35 and penetrate into and out of the cylindrical member 33 (see FIG. 2). The guide body 21 is disposed so as to cover the poppet valve 20 from the opening side of the cylindrical member 33, and the sliding hole 35 is fitted into the shaft 30 of the poppet valve 20 and abuts on the valve 29. . The cylindrical member 33 of the guide body 21 is slidably fitted on the outer periphery of the projection 24 with a gap from the inner periphery of the block 16.

With this configuration, the cylindrical member 33 of the guide body 21
The sliding hole 35, the convex portion 24 of the valve seat member 19, and the valve seat 27 are arranged substantially coaxially, and the space inside the guide body 21 communicates with the low pressure port 9 through each communication hole 36.
Further, the poppet valve body 20 is slidably held by the guide body 21 on the valve seat member 19 side which is the shortest distance from the valve seat member 19. Further, the poppet valve body 20
When the valve is closed, the guide member 21 that slides on the outer periphery of the convex portion 24 of the valve seat member 19 guides the portion near the valve seat member 19.
Even if it vibrates upon receiving the working water jetted to the back pressure chamber B side through 6, the vibration range is small, so that the valve seat member 19 is hardly hit.

Next, the operation of the hydraulic relief valve 1 will be described. For convenience of explanation, the hydraulic relief valve 1 is in the state shown in FIG. 1 and the main valve PB and the pilot valve CB are closed.

The hydraulic pressure of the working water from the high-pressure port 8 passes through the throttle hole 12 of the valve member 5 and the stepped passage 13 to the intermediate chamber A
Will be introduced. The hydraulic pressure of the working water introduced into the intermediate chamber A is
Further, it acts on the poppet valve body 20 through the throttle hole 25 and the valve seat hole 26 of the valve seat member 19. Then, when the working water becomes equal to or higher than a predetermined pressure, the poppet valve body 20 causes the valve spring 2
The pilot valve CB is opened by separating from the valve seat 27 against the valve seat 2. At this time, since the poppet valve body 20 is separated from the valve seat 27 while being guided by the valve seat member 19 by the guide body 21 sliding on the outer periphery of the convex portion 24, the poppet valve body 20 passes through the valve seat hole 26 from the intermediate chamber A. The vibration range is small even when receiving the working water spouting into the guide body 21.

When the pilot valve CB is opened and the working water is ejected from the valve seat hole 26 of the valve seat member 19 into the guide body 21 through the space between the poppet valve bodies 20, the communication holes 36 are formed at equal intervals in the bottom plate 34. Therefore, the operating water ejected from the valve seat hole 26 of the valve seat member 19 is supplied to the bottom plate 3 between the communication holes 36.
4 acts substantially uniformly, and reduces the inclined sliding of the guide body 21, thereby preventing the projections 24 of the cylindrical member 32 from being twisted.

The operating water flowing out into the back pressure chamber B passes through the passage 2
8, flows into the low pressure port 9 through the gap passage 14. When the working water flows into the low pressure port 9 from the back pressure chamber B, a pressure difference is generated between the intermediate chamber A side and the high pressure port 8 side, and the valve member 5 of the main valve PB is caused by the water pressure on the high pressure port 8 side to operate the valve spring 7. , The main valve PB is opened.

When the main valve PB is opened, the high-pressure port 8 and the low-pressure port 9 communicate with each other through the through holes 6a of the socket 6, so that the hydraulic water flows from the high-pressure port 8 to the valve seat 4 and the valve member 5. To the low pressure port 9. When the working water is continuously discharged to the low pressure port 9 and the water pressure falls below a predetermined pressure, the poppet valve body 20 is seated on the valve seat 27 by the valve spring 22 against the water pressure applied through the throttle hole 12 or the like. Then, the pilot valve CB is closed.

As a result, the pressure of the high pressure port 8 acting on the valve member 5 and the pressure of the back pressure chamber B become equal, and the valve member 5 is seated on the valve seat 11 by the valve spring 7 and the pilot valve C
B is closed. When the water pressure of the intermediate chamber A becomes equal to or higher than the predetermined pressure again, the above operation is repeated to control the water pressure of the working water of the high pressure port 8.

In the hydraulic relief valve 1 of the present invention, the poppet valve element 20 of the pilot valve CB is slidably held by the guide member 21 toward the valve seat member 19, and is separated from and seated on the valve seat member 19. Therefore, the poppet valve body 20 can be guided by the valve seat member 19 approaching. Accordingly, since the vibration width can be reduced by setting the axial length of the poppet valve body 20 to the minimum length, the processing accuracy of the members 19, 20, and 21 is not particularly increased only by considering the vibration width. The vibration of the poppet valve body 20 can be effectively suppressed.

FIG. 3 shows a modification of the hydraulic relief valve 1. In the hydraulic relief valve 1 of FIG. 3, the shape of each communication hole 36 of the guide body 21 is changed. Each communication hole 36
As shown in FIG. 4, four openings are formed at equal intervals around a sliding hole 35 of the bottom plate 34, and the cylindrical member 3 is continuously connected to the opening.
3, and the opening area is increased.
With this configuration, the valve seat member 21 is opened when the pilot valve CB is opened.
The hydraulic water spouted from the valve seat hole 26 flows out into the back pressure chamber B from each of the communication holes 36 whose opening is enlarged. Therefore, it is possible to reduce the influence of the ejection working water on the poppet valve body 20.

In the hydraulic relief valve 1 according to the present invention, the guide body 21 and the poppet valve body 20 are formed separately, but the invention is not limited to this. May be integrally formed.

Further, as shown in FIG. 5, the guide member 21 may be arranged in the valve seat member 19, and the port valve member 20 may be slid together with the guide member 21. In FIG. 5, the guide body 21 is formed in a disc shape having communication holes 36 at equal intervals, and is slidably disposed in the valve seat hole 26 of the valve seat member 19. Further, the guide body 21 is integrated with the shaft portion 30 of the poppet valve 20 seated on the valve seat member 19, and receives the valve spring 22 to move the poppet valve 20 to the valve seat 2.
7 is pressed (biased). Reference numeral 38 denotes a through hole formed in the convex portion 24 of the valve seat member 19, and the valve seat hole 26 and the back pressure chamber B
And communicate with. In this configuration, since the poppet valve body 20 is held by the guide body 21 and the valve seat member 19 at the close positions, the guide body 21 and the valve seat hole 26 are separated from the pressure chamber A through the throttle 25 and the valve seat hole 26. The vibration range can be reduced even when receiving the working water jetted into the space defined by the above.

The hydraulic relief valve 1 of the present invention comprises a guide body 21 provided on a poppet valve body 20 of a balance piston type relief valve.
Is applied, but the present invention can also be applied to a valve member 5 of the main valve PB or a direct acting relief valve operated only by the main valve PB.

[0031]

According to the hydraulic relief valve of the present invention, the valve body seated on the valve seat member is slidably held on the valve seat member side by the guide body. Accordingly, when the valve body is held by the valve seat member located at a position close to the valve body, the vibration width of the valve body due to the operating water ejected from the valve seat member can be suppressed to a small extent. Therefore,
The vibration of the valve body can be suppressed without particularly increasing the processing accuracy of the guide body, the valve seat member, and the like that hold the valve body.

A guide body is slidably provided on a cylindrical projection and is integrated with the valve body. Thus, by forming the columnar projection projecting from the valve seat member, the sliding surface of the projection on which the guide body slides can be easily processed.

It is formed substantially coaxially with the valve seat on which the convex portion and the valve element are seated. As a result, the convex portion and the valve seat can be simultaneously processed, and the manufacturing cost can be reduced.

The guide body is formed in a cylindrical shape with a bottom, and a circular convex portion is formed in the valve seat member. Then, the cylindrical portion of the guide body is slidably fitted into the convex portion, and the valve body is integrally held by the sliding hole of the bottom plate. Further, a communication hole for communicating the guide body and the low pressure port is formed in the guide body. Accordingly, the guide body can be provided substantially coaxially with the valve seat member, so that the mutual axes of the valve body and the valve seat of the valve seat body can be easily adjusted.

When the communication hole is formed in the bottom plate of the guide body, the working water ejected from the valve seat member can flow out from the communication hole of the bottom plate directly into the low pressure port, and the influence of the reflected flow of the working water reflected by the bottom plate can be prevented. Feeding to the body can be reduced. In particular, when the communication hole is formed from the bottom plate of the guide body to the cylindrical portion and the opening is enlarged, the effect of the operating water ejected from the valve seat member on the valve body can be effectively reduced, and each communication hole is formed. It becomes remarkable by forming a plurality.

If a plurality of communication holes are formed at equal intervals around the bottom sliding hole, the working fluid ejected from the valve seat member can act on the bottom between the communication holes substantially uniformly, so that the guide body is formed. Of the valve seat member can be reduced, and the valve seat member can be slid smoothly without stiffness.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a hydraulic relief valve.

FIG. 2 is an enlarged view showing a guide member of the hydraulic relief valve of FIG.

FIG. 3 is a sectional view showing a modification of the hydraulic relief valve.

FIG. 4 is an enlarged view showing a guide member of the hydraulic relief valve of FIG.

FIG. 5 is an enlarged view showing a modified example of the guide member of the hydraulic relief valve shown in FIGS. 1 and 3.

FIG. 6 is a sectional view showing a conventional hydraulic relief valve.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Hydraulic relief valve 8 High pressure port 9 Low pressure port 15 Valve body 19 Valve seat member 20 Poppet valve element 21 Guide member 22 Valve spring 24 Convex part 33 Cylindrical material 34 Bottom plate 35 Sliding hole 36 Communication hole

Claims (7)

[Claims] A valve body having a valve hole in which a high-pressure port and a low-pressure port are opened; a valve seat member disposed in the valve hole between the high-pressure port and the low-pressure port; In a hydraulic relief valve including a valve body seated on the valve seat member and a valve spring for urging the valve body against the valve seat member, a guide body engaged with the valve seat member and the valve body A hydraulic relief valve, wherein the guide body holds the valve body so that the valve body can be separated from and seated on the valve seat member in the axial direction of the valve body. 2. The hydraulic relief valve according to claim 1, wherein a convex portion is formed on the valve seat member, and the guide body is slidably provided on the convex portion. 3. The hydraulic relief valve according to claim 2, wherein the convex portion is formed coaxially with a valve seat on which the valve element is seated. 4. The guide body is formed in a bottomed cylindrical shape having a bottom portion closing one end of a cylindrical portion, and has a sliding hole coaxially formed in the cylindrical portion at the bottom portion. The valve seat member has a circular convex portion formed coaxially with a valve seat on which the valve body is seated. The cylindrical portion of the guide body is slidably fitted into the convex portion, The valve body is inserted into a sliding hole in a bottom part, and a space between the guide body and the valve seat member is connected to the low-pressure port by a communication hole formed in the guide body. Item 2. A hydraulic relief valve according to Item 1. 5. The hydraulic relief valve according to claim 4, wherein the communication hole of the guide body is formed in the bottom. 6. The hydraulic relief valve according to claim 4, wherein the communication hole of the guide body is formed from the bottom portion to the cylindrical portion. 7. The hydraulic relief valve according to claim 4, wherein a plurality of communication holes of the guide body are formed at equal intervals around the sliding hole.