JP2567347Y2 - Ball 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 ball valve having a function of reducing the pressure on the downstream side to atmospheric pressure when the valve is closed.

[0002]

BACKGROUND OF THE INVENTION During closing a conventional example of a ball valve downstream pressure is stepped down to atmospheric pressure, shown in the longitudinal sectional view of FIG. FIG. 3 shows the valve closed state, in which the through hole 21a of the ball 21 is perpendicular to the flow direction of the valve 22, and the ball 21 is in a sealed state with the upstream seat 23 to close the flow. doing. The downstream seat 24 is also sealed with the ball 21, but the through hole 21 b formed in the ball 21 communicates the downstream side 22 a of the valve 22 with the body space 25 a of the body 25, The space 25a communicates with the outside through a through hole 25b provided in the body 25. Therefore, in the valve closed state shown in FIG. 3 , the pressure on the downstream side 22a drops to the atmospheric pressure.

Other means for communicating the downstream side 22a of the valve 22 with the body space 25a include providing a groove in the surface of the ball 21, providing a through hole through the back side of the seat 24 in the cap 26, Ball 21 of seat 24
There is a means for providing a groove on the contact surface with the contact.

[0004]

In the above-mentioned conventional ball valve, it is difficult to provide a hole in the ball or cap, and if a groove or hole is provided in the ball, the ball is repeatedly rotated.
There is a problem that the sheet is easily damaged by the work , and if the groove is provided in the sheet, the sheet becomes weak, becomes expensive, and has a short life. Ball valve of the present invention is, above
It was developed in view of the above-mentioned issues.
It is not necessary to provide a hole in the ball or cap,
It is not necessary to provide a groove in the seat
High durability that can be easily formed by simply changing
Ball valve .

[0005]

Means for Solving the Problems To achieve the above object,
Therefore, the present invention provides a ball having a through hole inside the body.
A ball valve rotatably provided via a pair of annular sheets
The body space between the pair of annular sheets and the outside
A communicating hole is formed in a part of the body, and the annular ring on the downstream side is formed.
The inside diameter of the ball in contact with the ball is D, and the ball
Assuming that the length in the through hole direction is L and the relationship between the two is D> L
In both cases, when the ball is in the fully closed position,
Form a gap between the inner diameter and both ends of the ball in the through hole direction.
And the downstream side communicates with the body space .

[0006]

The ball valve of the present invention is constructed as described above.
Therefore, when the valve is fully open, the ball
Contacting the upstream sheet and the downstream sheet in a sealed state
ing. For this reason, the fluid flows through the ball through hole from the upstream side.
Flows to the downstream side through the
It does not leak to the outside from the provided through hole. in this case,
The pressure in the body space is at atmospheric pressure by the through hole
However, the pressure upstream and downstream of the valve is
Has become.

Next, when the valve is fully closed, the ball
It comes into contact with the annular sheet on the upstream side and becomes hermetically sealed.
Does not flow into the body space. At the same time, with the ball
Unsealed due to gap between downstream annular sheet
To prevent the downstream fluid from flowing into the body space.
Then, the downstream side and the body space have the same pressure. Body
The space is at atmospheric pressure because it communicates with the outside through through holes.
The pressure on the downstream side also drops to atmospheric pressure.

For this reason, when the ball valve is closed,
Reach the goal of downstream pressure dropping to atmospheric pressure
However, at the same time, the body space is always kept at
Is particularly problematic in general ball valves.
No abnormal pressure rise in the body space
No damage will occur.

In the fully closed state, the ball and the ring
As a means to create a gap between
The inner diameter of the ring-shaped sheet in contact with the ball is determined by the direction of the ball
Larger than the length of
An arcuate gap between the end face and the inner edge of the downstream annular sheet
Is a very simple and easy way to
From the shape of the valve, except to provide a hole in the body
Just replace the downstream annular sheet with one with a larger inside diameter
It is possible to make the ball valve of the present invention very economically.
Can be.

[0010]

FIG. 1 shows an embodiment of a ball valve according to the present invention.
Explanation will be given based on the plane. Fig. 1 shows the ball valve of the present invention.
FIG. 2 is a longitudinal sectional view showing one embodiment of FIG.
Is a ball valve, 2 is a ball having a through hole 2a, 3 and
And 4 are the upstream and downstream annular seats, 5 and 6 are
And 6 is also called a cap. FIG. 1 shows the ball valve 1
This shows a state in which the valve is in an open state, and the ball 2 is on the upstream
Between the annular sheet 3 and the annular sheet 4 on the downstream side.
Both seats 3 and 4 and ball 2 are sealed.
And the lever handle 8 through the stem 7 Rotation
The valve 1 is opened and closed. A pair of ring-shaped body 5
Between the ports 3 and 4, there is provided a through hole 5a communicating with the outside.
You.

The ball 2 of the annular seat 4 on the downstream side is
The contacting inner diameter D is the length L of the ball 2 in the direction of the through hole 2a.
Ball 2 is rotated and fully closed
When the state is reached, the end face 2b of the ball 2 in the direction of the through hole 2a
And a gap A between the inner side of the downstream annular sheet 4 and the inner edge of the downstream annular sheet 4
Is generated. In the arc shown by the two-dot chain line in FIG.
The two arcs are the full arc for ball 2 shown in the figure.
The relative position of the downstream annular sheet 4 in the closed state is shown.
The inner and outer edge lines drawn for
The state where A occurs is shown. The right two arcs
Are the lines on the inner and outer edges of the similar upstream annular sheet 3.
There is a transparent space between the annular sheet 3 and the ball 2 on the upstream side.
No gap is generated, indicating that the device is in a sealed state. FIG.
Is an arc indicated by a two-dot chain line in FIG. 1 as described above.
Of the two left-handed arcs is indicated by a solid line.
The ball 2 having the through hole 2a is indicated by a dashed line.
You. That is, in the figure, the ball in the fully closed state is
When the transparent space A is formed when viewed from the front of the
FIG.

Next, the embodiment of the present invention shown in FIGS. 1 and 2 will be described.
The operation of the example will be described. First, FIGS. 1 and 2
As shown in the figure, when the ball valve 1 is in the fully open state,
Means that the ball 2 has an upstream annular seat 3 and a downstream annular seat
It is in sealing contact with the sheet 4. Therefore, the fluid
Is downstream from the upstream side 1a through the through hole 2a of the ball 2.
Flows to the side 1b, between the two sheets 3 and 4 in the bodies 5 and 6
Hole 5a formed in the body 5 by flowing into the body space 5b
Does not leak to the outside. In this case, the body space
The pressure of 5b is set to the atmospheric pressure by the through hole 5a.
However, the pressure of the upstream side 1a and the downstream side 1b is
Has become.

Next, when the valve 1 is fully closed,
2 comes into contact with the upstream annular sheet 3 to be in a sealed state.
Therefore, the fluid on the upstream side 1a does not flow into the body space 5b.
No. At the same time, between the ball 2 and the annular sheet 4 on the downstream side
In order that the unsealed caused the gap A, the downstream side 1b
Fluid flows into the body space 5b, etc.
b and the body space have the same pressure. The body space 5b
It communicates with the outside through the through hole 5a, and the pressure on the downstream side 1b
Also drops to atmospheric pressure.

Therefore, when the ball valve 1 is closed,
To reduce the pressure of the downstream side 1b to atmospheric pressure
But at the same time, the body space 5b is
Because it is always kept at atmospheric pressure, general ball valves
Abnormal pressure rise in the body space 5b
And no damage is caused by this.

In the fully closed state, the ball 2 and the downstream annular shape
As means for generating a gap A between the sheet 4 and
As in the embodiment shown in FIG.
The inner diameter D in contact with the ball 2 is the length of the ball 2 in the direction of the through hole 2a.
L and the through hole 2a of the ball 2 in the fully closed state
The end face 2b, which is an opening, and the inner edge of the downstream annular sheet 4;
It is very easy to create a bow-shaped gap A between
It is a simple and easy method.
5 except that a through hole 5a is provided.
It is only necessary to replace the gate 4 with one with a large inner diameter.
The ball valve 1 of the present invention can be produced economically.

[0016]

[Effect of the invention] The ball valve of the invention is described in detail above.
As described above, simply closing the valve stops the fluid flow.
At the same time as reducing the downstream pressure to atmospheric pressure.
Can be. When the valve is opened, the fluid is
Flows from the outlet to the downstream side. Moreover, compared to conventional methods
And very simple structure, easy to manufacture and economical
Not only is the target, but also
Also there is no danger of damage to the ring-shaped sheet, and it has excellent durability
ing. Also, because the body space is always open to the outside
In addition, the body space is not abnormally boosted,
No damage will occur.

[Brief description of the drawings]

FIG. 1 shows a fully open state of a ball valve according to an embodiment of the present invention.
It is a longitudinal cross-sectional view of a state .

FIG. 2 shows the fully closed state of FIG . 1 and is annular from the downstream side.
FIG. 4 is an explanatory diagram illustrating a relationship between a seat and a fully closed ball .

FIG. 3 is a longitudinal sectional view showing an example of a conventional ball valve.

[Explanation of symbols]

Reference Signs List 1 ball valve 2 ball 2a through hole 2b end face in ball through hole direction 3, 4- ring seat 5, 6 body 5a through hole A clearance D inner diameter in contact with ball of downstream seat L length in ball through hole direction

Claims (1)

(57) [Scope of request for utility model registration] 1. A ball having a through hole inside a body.
A ball valve rotatably provided via a pair of annular sheets
The body space between the pair of annular sheets and the outside
A communicating hole is formed in a part of the body, and the annular ring on the downstream side is formed.
The inside diameter of the ball in contact with the ball is D, and the ball
Assuming that the length in the through hole direction is L and the relationship between the two is D> L
In both cases, when the ball is in the fully closed position,
Form a gap between the inner diameter and both ends of the ball in the through hole direction.
A ball valve, wherein the downstream side communicates with the body space .