JPH11119837A - Valve disk guide structure for pressure reducing valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a valve disk guide structure for pressure reducing valve without causing any valve leakage for a long term by enabling a valve disk to displace from a valve shaft for a long term even if the valve shaft slants or decenters. SOLUTION: The valve shaft 14 separately formed by way of a joint material 13 formed separately at a lower part of a valve 12 is arranged. The valve disk 12 and the joint material 13 are jointed with an almost hemisphere surface 15 and an almost conical surface 16, and the joint material 13 and the valve shaft 14 are jointed with an almost hemisphere surface 17 and an almost conical surface 18. A lower part of the valve shaft 14 is freely slidably engaged with a valve shaft guide 21. The valve disk 12 energizes a valve opening 4 with a coil spring 23 through the valve shaft 14 and the joint material 13.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressure reducing valve used in a fluid system, and more particularly to a valve guide structure in which a valve is seated at a valve opening.

[0002] A pressure reducing valve applies a pressure on an outlet side to one surface side of a pressure responsive member formed of a diaphragm, a bellows or the like, and applies an elastic force of a pressure setting means formed of a coil spring or the like to another surface. By balancing the two loads, the pressure responsive member is displaced to open and close the valve body, and supply of high-pressure fluid on the inlet side is stopped, thereby maintaining the outlet side in a predetermined reduced pressure state. It is widely used in fluid systems such as steam.

The pressure reducing valve reduces the pressure of the high-pressure inlet fluid and supplies the fluid to the outlet. When the valve body does not close the valve port when the valve is closed, the fluid is originally supplied to the outlet. The high-pressure inlet side fluid that should not be leaked, so that the outlet side of the pressure reducing valve becomes the same high pressure state as the inlet side, so-called cutoff pressure increase, and various devices connected to the outlet side are damaged. And the like.

[0004]

2. Description of the Related Art Conventionally, Japanese Patent Application Laid-Open No. 5-113
No. 827 discloses a valve guide structure. This is because, by providing a separately formed valve shaft at the bottom of the valve body and joining them with a substantially hemispherical surface and a substantially conical surface, the valve body can be valved even if the valve shaft is inclined or eccentric. It is completely displaced to the mouth and can be completely closed.

[0005]

SUMMARY OF THE INVENTION In the above prior art,
Although leakage can be reliably prevented in the early stage of use, there is a problem that valve leakage occurs as the use period elapses. This is because foreign matter such as dust and scale bites into the joint formed by the substantially hemispherical surface and the substantially conical surface formed on the valve body and the valve stem.
This is because the valve body cannot be displaced with respect to the valve shaft.

Accordingly, a technical problem of the present invention is to provide a valve which can be displaced with respect to a valve shaft for a long period of time even if the valve shaft is tilted or eccentric, so that a pressure reduction which does not cause valve leakage for a long period. An object of the present invention is to provide a valve body guiding structure for a valve.

[0007]

Means for Solving the Problems The technical means of the present invention taken to solve the above technical problem is to form an inlet, a valve port and an outlet by valve casing, and to face the valve port. A valve body is disposed, a pressure responsive member cooperating with the valve body is provided, an outlet side pressure is applied to one surface of the pressure responsive member, and a setting force of a pressure setting means is applied to the other surface, and an outlet side is provided. When the pressure falls below a predetermined value, the pressure responsive member is displaced to open the valve body and supply the high pressure fluid on the inlet side to the outlet side to recover the pressure on the outlet side, and the pressure on the outlet side becomes the predetermined value. When the valve recovers to the value, the valve body closes, and in the pressure reducing valve that maintains the outlet side in a desired reduced pressure state, the valve shaft formed separately through a joining member formed separately under the valve body. The valve body and the joining member are joined by a substantially hemispherical surface and a substantially conical surface, and the joining member and the valve shaft are joined by approximately half. Surface and a substantially conical surface, the valve shaft is slidably fitted to a valve shaft guide formed in a valve casing, and the valve shaft or the valve body is urged in the valve opening direction by a spring. It is in the valve guide structure of the pressure reducing valve.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A valve body is elastically urged in the valve opening direction directly by a spring or via a valve shaft. If there is no operation of a pressure responsive member, the valve body is actuated by the force of the spring and the fluid pressure on the inlet side. It is in contact with the valve face. When the pressure on the outlet side becomes lower than the value set by the pressure setting means, the pressure responsive member is displaced to open the valve body. Then, when the pressure on the secondary side reaches the set value, the pressure responsive member is displaced to the original position, and the valve body closes the valve port with the spring and the fluid pressure.

The valve element and the joining member are joined by a substantially hemispherical surface and a substantially conical surface, and the joining member and the valve shaft are joined by a substantially hemispherical surface and a substantially conical surface. The joint member is displaceable with respect to the valve shaft. Therefore, even if the valve shaft is tilted or eccentric, the valve body is displaced integrally with the joint member with respect to the valve shaft, or displaces with respect to the joint member to completely close the valve port.

[0010] Even if foreign matter is caught in one joint between the valve member and the joint member or between the joint member and the valve shaft due to long-term use, the valve member can be displaced with respect to the valve shaft by the other joint portion. Yes, close the valve port for a long time to prevent valve leakage.

[0011]

An embodiment showing a specific example of the above technical means will be described (see FIG. 1). FIG. 1 shows a main part of a valve portion of the pressure reducing valve. An inlet portion 2 communicating with an inlet (not shown) by a valve casing 1, an outlet portion 3 communicating with an outlet, and a valve port 4
To form The valve port 4 is provided at the center where the valve seat 5 is screwed to the valve casing 1. A disc-shaped valve body 12 is arranged facing the valve port 4. The lower end surface of the valve seat 5 and the upper end surface of the valve element 12 are used as a seal surface.

A valve shaft 14 is disposed below the valve body 12 via a joining member 13. The joining member 13 is spherical and has an upper semi-spherical surface 15 joined to a substantially conical surface 16 formed below the valve body 12, and a lower semi-spherical surface 17 joined to a substantially conical surface 18 formed above the valve rod 14. I do. The valve shaft 14 has a cylindrical portion 19 at the upper end.
The valve body 12 is housed inside through a minute gap 20. The lower portion of the valve shaft 14 is slidably disposed in a guide hole 22 of a valve shaft guide 21 attached to the valve casing 1.
A coil spring 23 is provided between the valve shaft guide 21 and the valve shaft 14 to urge the valve body 12 in the direction of the valve port 4 via the valve shaft 14 and the joining member 13.

A piston 6 is mounted on the cylinder above the outlet 3.
7. A piston ring 8 and a tension ring 9 are attached to the piston 6, and a lower part of the piston 6 has a substantially hemispherical shape 10 and an operation rod 11 is extended. Operation stick 1
The lower end of 1 is formed in a spherical shape and is in contact with the center of the sealing surface of the valve element 12. A communication hole 24 that connects the upper surface and the lower surface of the piston 6 is formed in the center of the piston 6.

Next, the operation of the above embodiment will be described. When the balance between the setting force of the pressure setting means, which is applied to the pressure responsive section (not shown), and the pressure at the outlet section 3 is lost, that is, when the pressure at the outlet section 3 falls below a predetermined value, The responsive member is displaced to open a pilot valve (not shown) to supply the high-pressure fluid at the inlet 2 to the upper surface of the piston 6. The piston 6 is displaced downward by the high-pressure fluid, and the valve body 12 is also displaced downward to open the valve port 4.
The high pressure fluid of the inlet 2 is supplied to the outlet 3 to recover the pressure. In this case, the valve body 12 is a cylindrical portion 19 of the valve shaft 14.
Even if the flow of the flowing fluid is strong due to being surrounded by, there is no large inclination.

When the outlet 3 reaches a predetermined pressure, the pressure responsive section returns to its original position, the pilot valve closes, the supply of high-pressure fluid to the upper surface of the piston 6 is stopped, and the pressure on the upper surface of the piston 6 communicates. By being discharged from the hole 24, the valve element 1
2 and the valve shaft 14 are in close contact with the seal surface of the valve seat 5 due to the pressure difference between the coil spring 23 and the inlet / outlet. In this case, the valve body 12 is not greatly inclined by the cylindrical portion 19 of the valve shaft 14,
Almost the entire surface is seated on the valve seat 5 at the same time,
There is no impact seating with one end as a fulcrum, and there is no uneven wear.

The valve shaft 14 has a guide hole 22 of a valve shaft guide 21.
The valve body 12 and the joining member 13 are joined by the substantially conical surface 16 and the substantially hemispherical surface 15, and the joining member 13 and the valve shaft 14 are substantially Since the hemispherical surface 17 and the substantially conical surface 18 are joined, the valve body 12 absorbs the inclination and eccentricity of the valve shaft 14 and securely adheres to the seal surface of the valve seat 5 to prevent leakage. I do. Further, even if foreign matter is caught in one joint between the valve body 12 and the joint member 13 or between the joint member 13 and the valve shaft 14 due to long-term use, the valve body 12 is moved relative to the valve shaft 14 by the other joint. It is possible to prevent leakage for a long time.

In the above embodiment, the valve body 12 has a substantially conical surface, and the joining member 13 has a substantially hemispherical surface. Further, the substantially conical surface is formed on the valve shaft 14 and the substantially hemispherical surface is formed on the joining member 13, but the conical surface may be formed similarly.

[0018]

According to the present invention, the valve element and the joining member are joined by a substantially hemispherical surface and a substantially conical surface, and the joining member and the valve shaft are joined by a substantially hemispherical surface and a substantially conical surface. Even if it is eccentric, it is displaced with respect to the valve shaft integrally with the joining member,
Alternatively, it can be displaced with respect to the joining member. Therefore, even if a foreign object bites into one joint between the valve body and the joint member or between the joint member and the valve shaft due to long-term use,
The valve body can be displaced with respect to the valve shaft by the other joint, and the valve port can be completely closed for a long time to prevent valve leakage.

[Brief description of the drawings]

FIG. 1 is a partial sectional view of an embodiment of a valve body guiding structure of a pressure reducing valve according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Valve casing 2 Inlet part 3 Outlet part 4 Valve port 5 Valve seat 6 Piston 12 Valve body 13 Joining member 14 Valve shaft 15 Substantially semispherical surface 16 Substantially conical surface 17 Substantially semispherical surface 18 Substantially conical surface 21 Valve shaft guide 23 Coil spring

Claims (1)

[Claims] An inlet, a valve port, and an outlet are formed by valve casing, a valve body is disposed opposite the valve port, and a pressure responsive member cooperating with the valve body is provided. When the pressure on the outlet side is applied to one surface and the setting force of the pressure setting means is applied to the other surface, and the pressure on the outlet side falls below a predetermined value, the pressure responsive member is displaced to open the valve body and open the inlet. A high-pressure fluid is supplied to the outlet side to recover the pressure on the outlet side, and when the pressure on the outlet side recovers to a predetermined value, the valve body closes, so that the outlet side is maintained at a desired reduced pressure state. In the valve, a separately formed valve shaft is provided through a separately formed joining member below the valve body, and the valve body and the joining member are joined by a substantially hemispherical surface and a substantially conical surface. The valve shaft is joined by a substantially hemispherical surface and a substantially conical surface, and the valve shaft is slidable on a valve shaft guide formed in a valve casing. And a valve body guiding structure of the pressure reducing valve in which the valve shaft or the valve body is urged toward the valve opening by a spring.