JPH08178120A - Ball valve - Google Patents

Abstract

PURPOSE: To provide a ball valve of one-piece structure preventing leakage of inside fluid from the circumference of a stem even when a handle is removed. CONSTITUTION: A stem hole 1c to insert a stem 2 into it and a packing chamber 1d are formed on a valve body 1, and the stem 2 to revolve the valve body 1 is provided. A packing 11 is arranged in the packing chamber 1d, a ground 12, a disc spring 13 and a pressure welding plate 9 are sequentially put on the stem 2, and they are firmly fastened by a first nut 7. Thereafter a handle 10 is provided on the stem 2, and it is fastened with a second nut 8. As fastening of the packing 11 and installation of the handle 10 are respectively carried out by different means, even when the handle 10 is removed, the first nut 7 is never loosened, and as the packing 11 is constantly made pressure contact with the packing chamber 1b, fluid leakage is never caused around the stem 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ball valve used for controlling the flow of water, oil, gas or the like in a pipe, and in particular, a packing provided by a nut or the like provided on a stem for rotating a valve body. The present invention relates to a so-called one-piece structure ball valve that presses against a valve body, in which the packing does not loosen and fluid inside the valve does not leak even if the handle is removed.

[0002]

2. Description of the Related Art Various types of ball valves are known, and a floating type ball valve 2 as shown in FIG.
0 is used. This type of ball valve 20 is generally referred to as a one-piece structure. The valve body 21 has a fluid inlet 21a and a fluid outlet 21b at both ends, and a stem hole 21c at the side portion thereof. A packing chamber 21 is provided around the stem hole 21c on the outer surface.
d is formed.

The valve body 21 is internally provided with a spherical valve element 23 sandwiched between a pair of seat rings 22, 22 and a stem 25 for rotating the valve element 23.
And a packing 26 is provided in a packing chamber 21d formed around the stem hole 21c. Stem 25
Has a collar portion 25a integrally formed at a position near the lower end portion, while a screw portion 25b for tightening the packing 26 is formed at the upper end portion. The reference numeral 24 indicates the valve body 2.
3 is an insert member for holding the valve body 21 at a fixed position.

A nut 27 is attached to the thread portion 25b of the stem 25.
Is screwed on, and the handle 27 is attached to the stem 2 with this nut 27.
It is fixed at 5. At this time, the tightening force of the nut 27 presses the disc spring 29 and the gland 30 against the back surface of the handle 28 in the direction of the valve body 21.
6 is compressed toward the valve body 21 and bulged in the centripetal direction, and the packing 26 is brought into close contact with the stem 25 to seal a slight gap between the stem hole 21c and the stem 25, thereby preventing fluid leakage around the stem 25. Configured to prevent.

[0005]

However, as can be seen from the above description, in the conventional one-piece ball valve 20 having the one-piece structure, the packing 26 is simply placed on the packing chamber 21d formed on the outer surface of the valve body 21. Since the pressure contact of the packing 26 to the valve body 21 is also used for mounting the handle 28, the ball valve 2
The handle 28 cannot be removed while the 0 is mounted on the pipe.

That is, in the conventional ball valve 20, when the nut 27 on which the handle 28 is mounted is loosened, the back surface of the handle 28 cannot press the disc spring 29 or the gland 30 and the packing 26 is unfastened. However, there is a problem that the fluid flowing in the ball valve 20 leaks from a slight gap between the stem hole 21c and the stem 25.

Further, the handle of the valve is often desired to be arbitrarily removed depending on the user's convenience, and it has been desired to develop a one-piece ball valve in which the handle can be freely attached and detached. The present invention has been developed in view of such problems of the conventional example, and an object of the present invention is to prevent fluid leakage due to unfastening of packing even if the handle is removed.
An object is to provide a one-piece ball valve in which the handle can be freely attached and detached.

[0008]

In order to solve the above-mentioned problems, a spherical valve body sandwiched by a pair of seat rings is installed in a valve body having a fluid inlet and outlet and a stem hole. At the same time, a stem for rotating the valve body is provided in the stem hole, and a packing chamber is formed around the stem hole on the outer surface of the valve body to arrange the packing, and the threaded portion formed on the stem is screwed. In the ball valve in which the handle is tightened with the nut and the packing is pressed against the valve body on the back side of the handle, the first nut and the second nut are screwed to the threaded portions formed on the stem, and the packing is performed with the first nut. The valve body was pressed against the valve body and the handle was attached to the stem with the second nut.

[0009]

In the ball valve of the present invention constructed as described above, the packing provided in the packing chamber is pressed against the valve body due to the tightening action of the first nut screwed to the stem, thereby achieving a good sealing property. Has been secured. At this time, since the handle provided on the stem is fixed by the second nut independent of the first nut, even if the second nut is loosened to remove the handle, the tightening force of the first nut is not affected. Since the packing can always be kept pressed against the valve body with an appropriate tightening pressure, the internal fluid of the valve body does not leak around the stem. The ball valve of the present invention has a simple structure, is easy to implement, and can be provided at a low cost.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the ball valve of the present invention will be described in detail with reference to the drawings. 1 and 2 show the ball valve of this embodiment. According to this, the fluid inlet 1a and the fluid outlet 1b are provided at both ends of the valve body 1, and the stem hole 1c through which the stem 2 is inserted is provided on the upper surface, and the stem hole 1c on the outer surface of the valve body 1 is A packing chamber 1d is formed around it. In the valve body 1, the flow path 4a held between the two seat rings 3 and 3 is provided.
The spherical valve body 4 having the above is internally mounted, and is held at an appropriate position by the insert member 5.

On the other hand, the stem 2 for rotating the valve body 4 is integrally formed with a collar portion 2a at a position near a lower end portion thereof.
A thrust washer 6 is provided on the top. Also, stem 2
A threaded portion 2b for screwing the first nut 7 and the second nut 8 is formed on the upper end of the stem 2, and the side surface of the stem 2 is used when a pressure contact plate 9 or a handle 10 to be described later is inserted. For positioning and prevention of idling, for example, two parallel surfaces are chamfered as shown in FIG. In addition,
This chamfer may be only one side.

A stem 2 incorporated in the valve body 1.
The packing 11 and the gland 12 are sequentially inserted into the packing chamber 1d, and then the disc spring 13 and the pressure contact plate 9 which are packing tightening means are inserted, and then the first nut 7 is inserted.
Is screwed onto the threaded portion 2b of the stem 2. In this case, the packing 11 is preferably made of, for example, carbon graphite, PTFE, or other airtight or watertight material so that good sealing characteristics can be obtained. Although only one packing 11 is illustrated in each drawing as an example, a plurality of packings 11 can be provided in the packing chamber 1d as needed.

In the present embodiment, the pressure contact plate 9 described above is
A stopper piece for restricting the rotation range of the valve body 4 is provided. This stopper piece corresponds to the stop piece 1e projecting in the vicinity of the stem hole 1c of the valve body 1, and is a fully closed stopper piece 9 for restricting the fully closed position of the valve body 4.
a and a full-open stopper piece 9b that regulates the full-open position. In the present embodiment, the turning range of the valve body 4 is 0 to 90 °. Further, a mounting hole 9c that is substantially similar to the cross-sectional shape of the stem 2 is bored in the center position of the pressure contact plate 9 to prevent the pressure contact plate 9 from idling.

Next, a handle 10 is provided on the stem 2.
Is attached. The handle 10 corresponds to the pressure contact plate 9 described above.
The through hole 10a having the same shape as the mounting hole 9c provided in the above is drilled, and the second nut 8 as the handle mounting means is screwed onto the threaded portion 2b of the stem 2 so as to be detachably mounted. In addition, the grip for opening and closing the handle 10 is provided with an insulation 10b made of vinyl resin or the like,
A display 10c indicating the opening / closing direction is written.

The handle 10 shown in the drawing is a conventional general-purpose product having a fully open position stopper 10e provided at the tip thereof, but in this embodiment, the pressure contact plate 9 is provided with stopper pieces 9a and 9b. Therefore, the fully opened position stopper 10e may be omitted. Further, the handle 10 may be detachably provided by a mounting means other than the second nut 8, for example, an appropriate fitting means (not shown). Further, the shape of the handle 10 is not limited to that shown in the figure, and various handles can be used.

FIG. 3 shows a second embodiment to which the present invention is applied. Since the basic structure of this embodiment is the same as that of the first embodiment, FIGS. 1 and 2 are used for details. Therefore, in this embodiment, constituent elements having the same functions as those of the first embodiment will be described using the same reference numerals.

In this embodiment, the stem 2 has packings 11,
The gland 12 is sequentially inserted, and the disc spring 13 and the flat washer 14 which are packing tightening means are inserted, and then the first nut 7 is screwed to the screw portion 2b of the stem 2. In this case, the flat washer 14 is to be installed if necessary.
It shall be arbitrarily provided depending on the implementation.

Next, a handle 10 is attached to the top of the stem 2.
Is attached. The same handle 10 as that shown in FIG. 1 is used as the handle 10, and is the second handle mounting means.
The nut 8 is detachably mounted by screwing it onto the threaded portion 2b of the stem 2. In this embodiment, the handle 1
0 also serves as a stopper that regulates the rotation range of the valve body 4.

That is, in the fully closed state of the valve body 4, the left side 10d of the handle 10 has the stop piece 1 of the valve body 1.
In addition, the full-opening stopper piece 10e provided at the tip of the handle 10 is configured to come into contact with the side surface 1f of the e and the other side surface 1g of the stop piece 1e when the valve body 4 is fully opened. In the present embodiment, the turning range of the handle 10 (valve body 4) is 0 to 90 °. in this case,
Since the handle 10 that restricts the rotation range of the valve body 4 is mounted on the first nut 7 that tightens the packing 11, the stop piece 1e protruding from the valve body 1 is the same as that of the first embodiment. It is necessary to form it a little longer than that.

In each of the above-mentioned embodiments, the one-piece floating ball valve is explained as an example. However, the packing chamber is formed on the outer surface of the valve body and the packing is tightened with the nut provided on the stem. If so, the present invention can be applied not only to the ball valve but also to valves and cocks having other shapes.

Next, the operation of this embodiment will be described. According to the above-described configuration, the pressure contact plate 9 (the flat washer 1 is fixed by tightening the first nut 7 screwed to the screw portion 2b of the stem 2).
4) presses the disc spring 13 against the metal gland 12, and the packing 11 provided in the packing chamber 1d is tightened.
As a result, the packing 11 is compressed in the packing chamber 1d of the valve body 1 and bulges in the centripetal direction to come into close contact with the stem 2 to seal a slight gap between the stem 2 and the stem hole 1c to seal this portion. Prevents fluid leakage from. In this case, since the collar washer 2a formed on the stem 2 is provided with the thrust washer 6, the first nut 7
The rotation of the stem 2 is not hindered by tightening.

On the other hand, the handle 10 is attached to the stem 2 with the second nut 8. In this embodiment, when the handle 10 is rotated in the S direction according to the opening / closing direction display 10c (S ← → O) written on the handle 10, the valve body 4 is fully closed, and conversely, the handle 12 is moved in the O direction. When rotated, the valve body 4 is fully opened.

As described above, the handle 10 has the second nut 8
Since it is attached to the stem 2, it can be easily attached and detached as required. Therefore, even if the handle 10 is removed from the stem 2 in order to prevent an erroneous operation or a mischievous operation, the first nut 7 does not loosen, and the packing 11 is still pressed against the inside of the packing chamber 1d to maintain a good sealing property. The fluid inside the valve does not leak from around the stem 2. Further, even if the handle 10 is accidentally stolen, fluid leakage does not occur.

At this time, in the fully closed state of the valve body 4, the fully closed stopper piece 9a of the press-contact plate 9 provided on the stem 2 contacts the side surface 1f of the stop piece 1e projectingly formed on the valve body 1 to It prevents the body 4 from being squeezed too much. Further, in the fully opened state of the valve body 4, the fully open stopper piece 9b of the pressure contact plate 9 comes into contact with the other side surface 1g of the stop portion piece 1e to prevent the valve body 4 from opening too much. Therefore, even when the handle 10 is removed, the rotatable range of the valve body 4 can be restricted,
It is possible to prevent troubles in fluid control due to excessive opening or throttling of the valve body 4.

In the ball valve of this embodiment, the parts used in the ball valve 20 of the conventional example shown in FIG. 5 can be used as they are, and since it has a simple structure, it can be easily implemented and is inexpensive. Can be provided to.

The third embodiment shown in FIG. 4 is a one-piece floating ball valve using a T-shaped handle 10. In the description of the present embodiment, members having the same configurations and operations as those of the above-described embodiments are designated by the same reference numerals, and the portions overlapping with the description of each of the above-mentioned embodiments are not described. Since the description of the parts is omitted, please refer to the above description of each embodiment for these parts.

In the ball valve of this embodiment, a plurality of, for example, two annular grooves 2d, 2d are formed in the stem 2 which is inserted through the stem hole 1c without forming the packing chamber 1d in the valve body 1 and providing the packing 11. Forming an annular groove 2d, 2d
The O-rings 15 and 15 which replace the packing 11 are provided respectively. In this case, the O-rings 15 and 15 can be made of various materials such as NBR and fluororubber. In this embodiment, for example, an O-ring 15 made of NBR is arranged in the lower annular groove 2d, and a fluorine rubber O-ring 15 is arranged in the upper annular groove 2d.

Further, in the ball valve of this embodiment, the T-shaped handle 10 is snap-fitted to be attachable to and detachable from the stem 2. This is the fitting groove 2 near the upper end of the stem 2.
On the other hand, the protrusion 10i is formed on the inner wall surface of the fitting hole 10h of the handle 10 so that the two 2c and 10i are fitted to each other. This handle 1
0 is integrally formed of plastic, for example. In this case, although not shown, the stem 2 is chamfered, and the fitting hole 10h of the handle 10 has a hole having substantially the same shape as the cross-sectional shape of the stem 2, Prevents 10 idle rotations.

Next, the operation of this embodiment will be described. According to the configuration described above, the O-rings 15, 15 provided in the annular grooves 2d, 2d of the stem 2 have an appropriate elastic force,
The O-rings 15, 15 are compressed into the annular grooves 2d, 2d of the stem 2 by the stem hole 1c formed in the valve body 1, and the elastic force of the O-rings 15, 15 causes the stem 2 and the stem hole 1
Stick to c. As a result, a slight gap generated between the stem 2 and the stem hole 1c is sealed to prevent fluid leakage from this portion. However, the O-ring 15,15
Since is a soft material having an appropriate elastic force, it does not hinder the rotation of the stem 2 while ensuring a good sealing property.

In this case, since the O-ring 15 is provided in double, the sealing property is very good, and the fluid flowing in the valve does not leak. Moreover, in this embodiment, the O-ring 15 made of fluororubber is arranged in the upper annular groove 2d,
Since the OBR ring 15 made of NBR is arranged in the lower annular groove 2d, it is possible to deal with control of all fluids and enhance the reliability of the ball valve. That is, NBR exhibits good sealing properties against various gases, and fluororubber has excellent chemical resistance and heat resistance. Further, since the work such as the retightening of the packing is not required at all due to its structure, the maintenance is easy.

Since the handle 10 of this embodiment is snap-fitted to the stem 2, it can be easily attached and detached as required. That is, when removing the handle 10, it can be easily removed by pulling the handle 10 upward. Also, when mounting the handle 10, the handle 1
It can be easily installed by aligning the 0 fitting hole 10h with the stem 2 and pushing it downward. Furthermore, since this embodiment has a simple structure, it can be easily implemented and can be provided at low cost.

[0032]

As is apparent from the above description, the ball valve of the present invention has the following excellent effects. That is, since the packing pressure contact means is provided separately from the handle mounting means, even if the second nut, which is the handle mounting means, is loosened in order to remove the handle,
There is no influence on the tightening force of the first nut, which is the pressure contacting means of the packing, and the packing can always be kept pressed against the valve body with an appropriate tightening pressure. The fluid inside the body will not leak.

As a result, the handle can be freely attached and detached as needed, and the packing does not loosen even if the handle is removed to prevent erroneous operation or tampering.
The fluid in the valve does not leak from around the stem of the ball valve. In addition, even if the handle is accidentally stolen, fluid leakage does not occur. Further, according to the present invention, since the components of the conventional ball valve can be used as they are, it is possible to provide an inexpensive product having a high commercial value.

[Brief description of drawings]

FIG. 1 is an exploded perspective view showing an embodiment of a ball valve of the present invention.

FIG. 2 is a vertical sectional view taken along the line AA of FIG.

FIG. 3 is a vertical sectional view showing a second embodiment of the ball valve of the present invention.

FIG. 4 is a vertical sectional view showing a third embodiment of the ball valve of the present invention.

FIG. 5 is a vertical cross-sectional view showing a conventional ball valve.

[Explanation of symbols]

 1 Valve Body 1a Inlet 1b Outlet 1c Stem Hole 1d Packing Chamber 2 Stem 2b Screw Part 3 Seat Ring 4 Valve Disc 7 First Nut 8 Second Nut 10 Handle 11 Packing

Claims (1)

[Claims] 1. A valve body having a fluid inlet, a fluid outlet, and a stem hole is provided with a spherical valve element sandwiched between a pair of seat rings, and a stem for rotating the valve element is provided in the stem hole. In addition, a packing chamber is formed around the stem hole on the outer surface of the valve body to arrange the packing, and the handle is tightened with the nut screwed to the thread formed on the stem, and the packing is fixed to the valve body. In a ball valve that presses, a first nut and a second nut are screwed onto the threaded portion formed on the stem,
A ball valve in which a packing is pressed against a valve body with a first nut and a handle is attached to a stem with a second nut.