JP2711596B2 - Control valve - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control valve for closing and controlling the flow of various fluids in a pipeline, and more particularly to a control valve which requires a small operating force to operate the control valve and has a small valve leakage. About. The control valve is used to control the flow of various fluids. Particularly when the fluid pressure is high, the pressure difference acting on the primary side and the secondary side of the valve member increases, A very large operating force is required to operate the valve member.

[0002]

2. Description of the Related Art Conventionally, a so-called cage valve as disclosed in Japanese Patent Publication No. 2-18470 has been used.
This is a case consisting of a cylindrical peripheral wall and a valve plug in the valve chamber.
A window for passing fluid and a plurality of valve seats are provided on the peripheral wall, a seating portion corresponding to the valve seat is provided on the valve plug, and a through hole communicating the upper and lower sides of the valve plug is provided. Then, the valve plug is slid up and down to change the opening area of the fluid passage window to control the flow. The pressure difference acting in the up and down operation direction acts almost equally on the top and bottom of the valve plug by the through hole of the valve plug, and is canceled out, and hardly acts on the valve plug. Is what you can do.

[0003]

SUMMARY OF THE INVENTION In the above prior art,
There has been a problem that valve leakage cannot be completely eliminated when the valve is closed. This is because valve seats are formed on the upper and lower portions of the cylindrical peripheral wall, respectively, and the upper and lower two valve seats must be simultaneously sealed by a plurality of seating portions provided on an integral valve plug. This is because it requires extremely high processing accuracy and is practically difficult.

Further, when a high-pressure fluid passes through, especially when the valve opening degree is small, the valve seat and the seating portion are throttled and high-speed fluid flows down, causing erosion damage. There is also a problem that the airtightness is reduced and the valve leakage is further promoted.

Accordingly, a technical problem of the present invention is that, even when controlling a high-pressure fluid, the operating force for operating the valve section is small, and the valve does not require high machining accuracy for a long period of time. The goal is to obtain a leak-free control valve.

[0006]

In order to solve the above-mentioned technical problems, the technical means of the present invention is to form an inlet, a valve chamber and an outlet in a valve casing, and to define the inlet and the outlet in the valve chamber. A cylindrical valve member and a disc-shaped valve seat member are disposed to face each other, and a fixed wall is disposed inside the cylindrical valve member to form a pressure chamber.
Forming and communicating the pressure chamber with the inlet to the valve member
With a communication hole, the disk-shaped valve seat member
And a plurality of through holes communicating with the outlet.
A plurality of sub-valves are arranged to face the through holes, and the plurality of sub-valves are
The cylindrical valve members cooperate with each other to delay the opening of the valve members .
Sub-valve is opened, a plurality of auxiliary valve is closed prior to the closing of the valve member.

[0007]

The operation of the above technical means is as follows.
By forming the pressure chamber for receiving the inlet pressure in the valve member, the pressure difference between the inlet side and the outlet side acting on the valve member is offset, and the valve member can be operated with a small operating force. Also, by providing a sub-valve that opens after the valve member is opened and closes before the valve member closes, the sub-valve is closed even when the valve member is slightly opened. The high-speed fluid does not flow down the valve member, causing no erosion damage. Even when the valve member goes from opening to closing, the sub-valve closes before closing the valve member. As a result, the flow path of the valve member is not restricted, and
No John damage occurs.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment showing a specific example of the above technical means will be described. First embodiment (see FIG. 1). An inlet 2, a valve chamber 3 and an outlet 4 are formed by a valve casing 1.
The valve seat member 5 is attached to the valve casing 1 in the valve chamber 3.
The valve seat member 5 has a substantially disk shape and is provided with a plurality of through holes 6 communicating the inlet 2 and the outlet 4. An inverted cylindrical valve member 7 is arranged above the valve seat member 5. The lower end 8 of the valve member 7 faces the valve seat member 5 to form a seal surface. Section T inside the valve member 7
A lower wall 9 is provided with a female screw 10 provided on the valve seat member 5. The upper portion of the fixed wall 9 has a disk shape and is in contact with the inner periphery of the valve member 7 via the seal member 11. A pressure chamber 12 is formed by the upper surface of the fixed wall 9 and the inner peripheral surface of the valve member 7, and a communication hole 13 that communicates the pressure chamber 12 with the inlet 2 side.
Are provided. A step portion is provided below the valve member 7 so that the sub-valve 1
5 is attached with a snap ring 16. The sub-valve 15 is composed of a plurality of rod-shaped members, and the lower part of the rod-shaped member slides in a through hole 6 formed in the valve seat member 5. An operation rod 17 for operating the valve member 7 from outside is attached to an upper portion of the valve member 7.

When the valve member 7 is closed (as shown in FIG. 1) and the operating rod 17 is pulled upward to open the valve, the pressure in the valve closing direction of the valve member 7 due to the high pressure fluid on the inlet 2 side. A part of the high pressure fluid on the inlet 2 side is offset by reaching the pressure chamber 12 through the through hole 13, and the valve member 7 can be opened with a small operating force.

When the valve member 7 is opened by the operating rod 17 in a small amount, since the lower end of the rod-shaped member of the sub-valve 15 is still inside the through hole 6, the flow of the fluid from the inlet 2 to the outlet 4 is small. The flow velocity of the fluid passing between the lower end 8 of the valve member 7 and the valve seat member 5 is low, so that there is no erosion damage.

When the valve member 7 is further moved upward, the rod-shaped member of the sub-valve 15 is completely separated from the through-hole 6 and a large amount of fluid at the inlet 2 flows down. In this case, the valve member 7 and the valve seat member 5
Since the distance between them is large, the flow path is not narrowed, and erosion due to the high-speed flow does not occur.

Second Embodiment (See FIG. 2) In this embodiment, the same members as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted. Seat below fixed wall 9
The seal holding plate 20 is arranged via the sealing member 11 and
The seal member 11 is attached by being urged upward by a coil spring 21 provided between the seal member 11 and the seal member 11. Seal member 11 and holding plate 2
The contact surface 22 with the taper 0 is tapered so that the pressure in the pressure chamber 12 is hardly released even when the seal member 11 is worn. Sub valve 1
The lower end of 5 is formed flat, and when the valve member 7 is displaced upward by a predetermined amount, the snap ring 16 comes into contact with the upper flange portion 23 of the sub-valve 15, and the sub-valve 15 opens the through hole 6.

[0013]

The present invention has the following specific effects. According to the present invention as described above, by canceling the pressure difference between the inlet side and the outlet side acting on the valve member by the pressure chamber provided in the valve member, the high differential pressure does not act on the valve member, Therefore, the valve member can be operated with a small operation force.

Further, by providing a sub-valve which opens after the valve member is opened and closes prior to closing the valve member, high speed fluid does not flow down the valve member and erosion damage is prevented. It does not occur. Therefore, the sealing property between the valve and the valve seat can be maintained for a long time in the initial high state,
No valve leakage occurs.

[Brief description of the drawings]

FIG. 1 is a sectional view of a main part of an embodiment of a control valve of the present invention.

FIG. 2 is a sectional view of a main part of another embodiment of the control valve of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Valve casing 2 Inlet 4 Outlet 5 Valve seat member 6 Through hole 7 Valve member 9 Fixed wall 12 Pressure chamber 13 Communication hole 15 Secondary valve

Claims (1)

(57) [Claims] An inlet, a valve chamber, and an outlet are formed by a valve casing, and a cylindrical valve member and a disc that define the inlet and the outlet in the valve chamber.
The valve seat members are arranged facing each other and the inside of the cylindrical valve member is
A pressure chamber is formed by disposing a fixed wall on the
Smell provided with a communication hole communicating the pressure chamber with the inlet
And a plurality of through holes communicating the inlet and the outlet with the disc-shaped valve seat member.
A through hole is provided, and a plurality of sub-valves are opposed to the plurality of through holes.
Was placed, with a delay in the opening of the plurality of secondary valves and a cylindrical valve member cooperate to <br/> valve member opens a plurality of auxiliary valve, a plurality prior to closing of the valve member tone <br/> Fushiben sub valve of which is characterized in that closed.