JPH0443664Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to a flow rate regulating valve connected to a fluid piping path.

[Prior Art] A flow rate adjustment valve is connected to a fluid piping path such as a water supply piping in order to adjust the flow rate of fluid flowing therein. Conventionally, various types of valves suitable for various conditions such as internal fluid pressure and flow velocity have been provided as valves for adjusting the flow rate. In particular, when the pressure difference between the inflow side and the outflow side is large and the opening/closing mechanism of the valve body, which seals the inside of the valve body, is subjected to a high load due to the high pressure on the inflow side, the pressure-receiving surface of the valve body A valve is used that is equipped with a mechanism that introduces fluid on the inflow side to the back surface of the valve body to apply pressure to both sides of the valve body, thereby reducing the force applied to the valve body opening/closing means.

As a conventionally known valve having the above-mentioned mechanism, for example, a valve shown in Japanese Patent Application Laid-Open No. 60-205083 has been provided, and this valve will be explained below with reference to FIG. 5.

In FIG. 5, reference numeral 1 indicates the valve body. This valve body 1 consists of a body 2 and a lid 3, which are firmly fixed to each other by bolts (not shown). The body 2 has a first piping port 2a on its side.
A second piping port 2b is formed therein, and a cylindrical leg portion 4 is formed on the lower surface. The inside of the body 2 has a first flow path 6a that communicates with the first pipe port 2a on the lower side and the second pipe port 2b on the upper side by means of a valve seat 5 provided near the center thereof. It is divided into upper and lower parts, such as a second flow path 6b. Further, a partition wall 7 is provided on the upper surface of the body 2, and the inner surface of the lid 3 fixed to the upper surface of the partition wall 7 and the upper surface of the partition wall 7 form the second flow path 6b in the upper part of the valve body 1. A pressure equalization chamber 8 is defined. A through hole 9 and a guide hole 10 are provided in a straight line in the valve seat 5 and the partition wall 7, and a shaft portion 11a of a valve body 11 is slidably fitted into the guide hole 10. This valve body 11 changes the gap between the lower surface 11c of a disc-shaped flange 11b provided at its tip and the valve seat 5 by moving the valve body 11 in the axial direction, so that the fluid passing through the through hole 9 The purpose is to change the flow rate of
The outer periphery of the lower surface 11c of the flange 11b is formed into a shape that can be brought into close contact with the valve seat 5 so as to completely block off the first flow path 2a and the second flow path 2b. There is. In addition, the shaft portion 11
The outer diameter D ₂ of a is the same as the inner diameter D ₁ of the through hole 9, and an internal space 12a that is open toward the pressure equalization chamber 8 is formed therein. The inner space 1 of the shaft portion 11a is provided on the lower surface of the valve body 11.
A plurality of small holes 12b are provided which communicate with the pressure introducing path 12 which connects the first flow path 2a and the pressure equalizing chamber 8 with the small holes 12b and the internal space 12a.
The pressure introduction path 12 introduces the fluid in the first flow path 2a into the pressure equalization chamber 8, so that the first flow path 2a and the pressure equalization chamber 8 are maintained at the same pressure. ing. Further, the upper part of the guide hole 10 of the partition wall 7 into which the shaft portion 11a is fitted is provided to prevent the fluid in the pressure equalization chamber 8 from leaking into the second flow path 2b through the small gap in the fitting part. To prevent this, an annular seal 13a is attached by a mounting member 13b.

On the other hand, above the valve body 11, the valve body 11
A valve rod 14 for moving the valve in the axial direction is provided with its axis aligned with the axis of the valve body 11. That is, the through hole 9 is formed at the top of the lid 3.
The shaft portion 14a is slidably inserted into the sealing material 15 provided in line with the guide hole 10, and the tip portion 14b is inserted into the upper surface 11d of the flange 11b.
It is firmly fixed at the center by a bolt (not shown), so that it can move coaxially with the valve body 11. Further, the other end (not shown) of the valve stem 14 is extended to the outside of the valve body 1 and connected to a drive device (not shown) that moves the valve stem 14 in the axial direction.

A thin cylindrical port member 16 that is open towards the first flow path 2a is fixed to the lower surface 11c of the flange 11b. It is designed to be able to move in the axial direction. This port member 16 has V-shaped ports 16b provided at several locations on its wall surface 16a, and the through hole 9
This is to regulate the flow of fluid passing through the valve body 11 and to alleviate the impact caused by changes in flow rate due to movement of the valve body 11.

In the valve having the above configuration, for example, the first
A fluid with a pressure p ₁ per unit area is flowing from the flow path 2a toward the second flow path 2b, and this
If we consider that the pressure p ₂ per unit area of the second flow path 2b is sufficiently small compared to p ₁ and its influence can be ignored, then the force that tries to push the valve body 11 upward
As for F ₁ , since D ₁ =D ₂ , it can be considered that the pressure p ₁ acts on an area equal to the cross-sectional area d of the shaft portion 14a of the valve stem 14, and F ₁ =p ₁ ·πd ² /4. Therefore, if the weight of the valve body 11 is W, and the diameter d of the shaft portion 14a is determined so that F ₁ =W, the force required to move the valve stem 14 in the axial direction is equal to 13a
It only needs to be large enough to overcome the sliding resistance of sliding parts such as the sealing material 15 and the sealing material 15, and the load on the drive device can be reduced.

[Problems to be solved by the invention] By the way, the above-mentioned conventional valve has the following problems.

That is, when moving the valve body 11 in the axial direction, the valve body 11 is guided by the guide hole 10, the valve stem 14 is guided by the sealing material 15, and the port member 16 fixed to the valve body 11 is guided by the through hole 9. You will be guided.
However, since these drive devices, valve body 11, valve stem 14, and port member 16 are fixed together,
In order to reduce the load on the drive device, that is, to move the valve body 11 smoothly, these drive device, valve stem 14, valve body 11, and port member 16 are required.
It is required that the axes of each of the constituent elements of the through hole 9 and the guide hole 10 coincide completely. Therefore, when assembling a valve with the above configuration,
The axes of each component had to be perfectly matched during assembly, but this was extremely difficult and some misalignment had to be tolerated. That is, taking the case of fixing the valve body 11 and the valve stem 14 as an example, since the valve body 1 has a sealed structure, the valve body 1 must be fixed before fixing the lid 3 to the body 2 and sealing the inside. 11 must be housed inside the body 2, and the valve stem 14 must also be fixed to the valve body 11 before the valve body 11 is assembled to the body 2, so the axes of both cannot be aligned. It is. In other words, if the valve body 11 and the valve stem 14 are fitted into the guide hole 10 and the sealing material 15 and then fixed, it is easy to align their axes, but in reality,
Since both have to be fixed without any such guide reference, it is extremely difficult to fix them with their axes aligned.

As described above, in the conventional valve described above, alignment of the axes of each component is extremely difficult, and conventionally it has been necessary to accept a certain degree of misalignment of the axes. Therefore, the purpose of reducing the operating force of the valve stem 14 was offset by the increase in sliding resistance, and the effect could not be fully exerted. This also caused the following problems.

That is, if the valve body 11 is moved with the axes of each component incompletely aligned, uneven wear will occur on each guide portion, and particularly on the sliding portions of the annular sealing member 13a and the sealing member 15 made of an elastic material. Significant uneven wear occurs and the sealing function deteriorates, eventually creating gaps in the sliding parts and causing fluid leaks.

This idea was developed against this background, and in a valve equipped with a valve stem operating force reduction mechanism, the valve stem operating force increases even if the axes of each component are not perfectly aligned. It is an object of the present invention to provide a valve that does not cause fluid leakage due to uneven wear.

[Means for Solving the Problems] In order to solve the above problems, this invention has a structure in which the inside of the valve body, which has the first and second piping ports formed on the side surface, is connected to the valve body with the first piping port on the lower side. a valve seat that is divided into a first flow path leading to the second flow path and a second flow path leading to the second piping port on the upper side; a partition wall that creates a pressure equalization chamber partitioned from the flow path;
a through hole provided in the valve seat so that the flow path and the second flow path communicate with each other; a guide hole provided in the partition wall so as to be located in line with the through hole;
The valve body, whose shaft portion is slidably fitted into the guide hole and whose tip portion is shaped so as to be able to come into close contact with the valve seat, communicates with the first flow path and the pressure equalization chamber. It is slidably inserted into a pressure introduction passage provided by penetrating the valve body, and a sealing material on the upper part of the valve body provided in a straight line with the through hole and the guide hole, and the tip thereof In the valve, the tip of the valve stem is connected to the valve body with a gap provided in the radial direction.

[Function] According to the above configuration, even if the axes of the guide hole and the sealing material do not completely match, the radial clearance provided at the tip of the valve stem allows the valve body and the valve stem to move radially, respectively. The valve body moves independently and enters the guide hole.
The valve stems fit into the sealing material and slide smoothly on the same axis.

[Embodiments] Hereinafter, embodiments of the present invention will be described with reference to FIGS. 1 to 4.

In FIG. 1, reference numeral 17 is the valve body. The valve body 17 consists of a body 18 and a lid 19 that are firmly fixed to each other with bolts (not shown). The body 18 has a first piping port 20a and a second piping port 20b formed on its side surface, and further has a cylindrical leg portion 21 formed at its lower part. The interior of the body 18 has a valve seat 22 provided near its center, which allows a first flow path 23a on the lower side to communicate with the first pipe port 20a and a second flow path 23a on the upper side to communicate with the second pipe port 20b. The flow path 23b is divided into upper and lower sections. In addition, the fuselage 18
A partition wall 24 is provided on the upper surface of the partition wall 24.
The second flow path 2 is formed in the upper part of the valve body 17 by the inner surface of the lid 19 fixed to the upper surface and the upper surface of the partition wall 24.
A pressure equalization chamber 25 partitioned off from 3b is defined. The fitting hole 2 provided in the valve seat 22 is
2a has a through hole 26a as shown in FIG. 2A.
A cylindrical sleeve 26 is fitted therein. Further, the fitting hole 2 provided in the partition wall 24
4a includes a cylinder member 2 as shown in FIG. 2B.
7 is fitted in the cylinder member 27, and a guide hole 27a is provided in this cylinder member 27 so as to be positioned in line with the through hole 26a of the sleeve 26.

As shown in FIG. 1, a shaft portion 28a of a valve body 28 is slidably fitted into the guide hole 27a. This valve body 28 is provided in order to change the amount of clearance with the valve seat 22 by moving it in the axial direction, thereby changing the flow rate of fluid passing through the through hole 26a. It is formed by fitting and welding a circular partition plate 28b to the upper end of the inner peripheral surface of the shaft portion 28a, which is made of a body, and welding a disk-shaped flange 28c against the lower end surface. Note that the outer diameter D ₂ of the shaft portion 28a is set to be the same as the inner diameter D ₁ of the through hole 26a. Further, as shown in FIG. 2A, an annular groove 28e having a rectangular cross section is formed in the outer peripheral portion of the lower surface 28d of the flange 28c, and an O-ring 29 is mounted in this annular groove 28e. This is the lower surface 28d and the upper surface 2 of the sleeve 26.
6b (hereinafter, this case will be referred to as the closed state of the flow path), this is provided to ensure that this part is in close contact and to prevent fluid leakage. .

Further, as shown in FIG. 1, the upper end surface 28f of the shaft portion 28a is set to be at the same height as the upper surface 27a of the cylinder member 27 when the flow path is closed. A pressure equalization chamber sealing plate (hereinafter abbreviated as sealing plate) 30 having a shape is fixed. This sealing plate 30 is provided so that the pressure equalizing chamber 25 is reliably sealed from the second flow path 23b when the flow path is closed. As shown in FIG. 2B, an annular groove 30b with a rectangular cross section is formed in the lower surface 30a, and an O-ring 31 is attached to this annular groove 30b. Further, as shown in FIG. 2A, a mounting hole 28g is provided on the lower surface 28d of the flange 28c, located coaxially with the shaft portion 28a.
As shown in FIG. 1, a thin cylindrical port member 33 that is open toward the first flow path 23a is fitted into the attachment hole 28g, and the through hole 26a of the sleeve 26 is fitted into the mounting hole 28g. The valve body 28 is guided by the valve body 28 so that it can move in the axial direction together with the valve body 28. This port member 33 has ports 33b formed in a combination of an inverted V shape and a square at several locations on its wall surface 33a.
This is for regulating the flow of fluid passing through a and alleviating the impact caused by changes in flow rate due to movement of the valve body 28.

The valve body 28 is provided with a pressure introduction path 34 that connects the first flow path 23a and the pressure equalization chamber 25 to maintain them at the same pressure. This pressure introduction path 34
are the inner circumferential surface of the shaft portion 28a and the partition plate 28b.
and an intermediate portion 34a defined by the flange 28c.
and an inflow hole 3 provided through the flange 28c.
4b, and a plurality of outflow holes 34 provided in a portion of the partition plate 28b inside the inner circumferential surface of the sealing plate 30.
It consists of c.

On the other hand, the through hole 26 is located at the top of the lid 19.
A sealing member 35 is provided in line with the guide hole 27a and the guide hole 27a, and a valve rod 36 for moving the valve body 28 is inserted into the sealing member 35 so as to be slidable in the axial direction. There is. The tip of the valve stem 36 is loosely connected to the valve body 28, and this connected portion will be described in detail below with reference to FIG. 3.

As shown in FIG. 3, the tip end 36a of the valve rod 36 is inserted into a communication hole 37a formed on the axis of the connection plate 37, and the end surface thereof is inserted into the locking hole 37b of the connection plate 37. The inserted locking bolt 38 is screwed in. Since the through hole 37a is set to be larger than the shaft diameter of the valve stem 36 and smaller than the outer diameter of the large diameter portion 38a of the locking bolt 38, the shoulder portion 38 of the locking bolt 38
c is the bottom surface 37 of the locking hole 37b of the connection plate 37
c, and the valve stem 36 is connected to the connection plate 37. The connecting plate 37 is fixed to the center of the upper surface of the partition plate 28b by bolts 39, and therefore the valve rod 36 is connected to the valve body 28 via the connecting plate 37. Since the inner diameter and depth of the locking hole 37b are set larger than the outer diameter and width of the large diameter portion 38a of the locking bolt 38, the valve stem 36
is connected to the valve body 28 with gaps provided in the radial and axial directions of its tip 36a.

The other end of the valve rod 36 extends upwardly outside the valve body 17 through the sealing member 35, as shown in FIG. There is. This drive device 40 is
It is provided to open and close the valve body 28 at a remote location isolated from the piping route to which the valve body 17 is connected.

In the valve having the above configuration, for example, the first
A fluid with a pressure p ₁ per unit area is flowing from the flow path 23a toward the second flow path 23b,
Compared to this p ₁ , the pressure p ₂ per unit area of the second flow path 23b is sufficiently small, and the force F ₁ which tries to push up the valve body 28 at the pipe port is considered to be negligible. Considering this, when the flow path is closed, the wall surface 3 of the port member 33
Since pressure p ₁ is applied to the lower surface of 3a, the upper and lower surfaces of flange 28c, the lower surface of partition plate 28b, and the upper surface of sealing plate 30, F ₁ =π·p ₁ (D ₁ ² −D ₃ ² )/4.

When the flow path is open, in addition to the case where the flow path is closed, pressure p ₁ is also applied to the outer peripheral edge of the lower surface of the sealing plate 30, so F ₁ =π・p ₁ (D ₁ ² −D ₃ ² + (D ₃ ² - D ₂ ² ))/4 = π・p ₁ (D ₁ ² - D ₂ ² )/4, and from D ₁ = D ₂ , F ₁ = 0, and the valve body 2
8 will not be affected by the pressure _p1 .

Even in the case where the flow path is closed, considering that the pressure p ₁ actually acts upward on the portion of the lower surface of the sealing plate 30 outside the O-ring 31, it can be assumed that F ₁ =0. Therefore, the force required to move the valve stem 36 in the axial direction is the weight of all components that cooperate with the valve body 28 plus the sliding resistance of sliding parts such as the sealing material 30. It gets better with size.

By the way, in the valve of this embodiment, the axes of the through hole 26a and the guide hole 27a and the sealing material 35 are
Even if the axes of the valve stem 36 and the guide hole 27a do not coincide with each other, since a radial gap is provided in the tip 36a of the valve stem 36, the valve body 28 is aligned on the axes of the through hole 26a and the guide hole 27a. The rods 36 each move on the axis of the seal 35 and are slidable exactly coaxially relative to the respective guide. Therefore, the problem that each component provided to reduce the operating force of the valve stem 36 cannot fully perform its function due to an increase in sliding resistance due to misalignment of the axes is resolved, and the problem that There is no need to worry about fluid leaks.

Next, another embodiment of the present invention will be described using FIG. 4. Note that explanations of the same components as in the above embodiment will be omitted.

In this embodiment, the connecting portion between the valve body 28 and the valve stem 36 is changed. As shown in FIG. 4, a small diameter portion 36b is provided at the tip of the valve stem 36, and this small diameter portion 36b is inserted into a mounting hole 28i provided at the center of the partition plate 28b. Note that this attachment hole 28i is formed to have a larger diameter than the small diameter portion 36b of the valve stem 36. A male thread 36c is formed at the tip of the small diameter portion 36b so that its raised position is located below the lower surface of the partition plate 28b, and by screwing a nut 41 into this male thread 36c and tightening the valve stem. 36
and the valve body 22 are connected. As a result, a gap is created between the inner circumferential surface of the attachment hole 28i and the outer circumferential surface of the small diameter portion 36b of the valve stem 36, and the axes of the through hole 26a and guide hole 27a and the sealing material 35 do not match, as in the above embodiment. can be absorbed.

In this embodiment, a so-called commercial product may be used as the nut 41 that connects the valve body 22 and the valve stem 36, so there is no need to manufacture a part corresponding to the connection plate 37 of the above embodiment. Therefore, the present invention can be easily implemented and has the advantage of being inexpensive.

In each of the above embodiments, the pressure equalizing chamber 25 and the valve body 2
The sealing with the shaft portion 28a of the valve stem 28a is not done with an outer circumferential seal that is always airtight like the annular sealing member 13a of the conventional example described above, but is made with a face seal that is airtight only when the flow path is closed. The special effect was that the resistance was lower.

[Effects of the invention] As explained above, this invention provides a gap in the radial direction at the connecting portion between the tip of the valve stem and the valve body. Therefore, the valve body and valve stem can move independently in the radial direction, so even if the axes of the guide hole and the sealing material do not match perfectly, the valve body moves into the guide hole, and the valve stem moves into the sealing material. It adapts to each other and can slide smoothly on its axis. Therefore, even if the axes of the components provided to reduce the valve stem operating force do not match perfectly, the valve stem operating force will not increase, and uneven wear will not occur, so fluid leakage will not occur. It never happens.

[Brief explanation of the drawing]

Figures 1 to 3 show an embodiment of the present invention, where Figure 1 is a sectional view of the valve body, Figure 2 is a partially enlarged sectional view of the valve body, and A is an enlarged view of the lower part of the valve body. sectional view, B is an enlarged sectional view of the upper part of the valve body, FIG. 3 is an enlarged sectional view of the connection part between the valve body and the valve stem, and FIG. 4 is the connection part between the valve body and the valve stem in another embodiment of the present invention. and FIG. 5 is a sectional view of a conventional valve. 17... Valve body, 20a... First piping port, 2
0b...Second piping port, 22...Valve seat, 23a...
...First channel, 23b... Second channel, 24...
Partition wall, 25... pressure equalization chamber, 26a... through hole, 27
a... Guide hole, 28... Valve body, 28a... Shaft portion,
34...Pressure introduction path, 35...Sealing material, 36...
Valve stem, 37...connection plate.

Claims (1)

[Scope of utility model registration request] The interior of the valve body, which has first and second piping ports formed on its side, is connected to a first piping port whose lower side communicates with the first piping port.
a valve seat that is divided so that the upper side becomes a second flow path leading to the second piping port; A partition wall that creates a partitioned pressure equalization chamber, a through hole provided in the valve seat so that the first flow path and the second flow path communicate with each other, and a through hole located in a straight line with the through hole. a guide hole provided in the partition wall, a valve body whose shaft portion is slidably fitted into the guide hole, and whose distal end portion is formed in a shape that allows close contact with the valve seat; A pressure introduction path is provided through the valve body so that the flow path and the pressure equalization chamber communicate with each other, and a sealing material on the upper part of the valve body is provided in a straight line with the through hole and the guide hole. A valve comprising a valve stem that can be inserted into the valve body and whose tip end is connected to the valve body, wherein the tip end of the valve stem is
A valve characterized in that the valve is connected to the valve body with a gap provided in the radial direction.