JPS5842698Y2 - Valve stem locking mechanism - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a valve stem locking mechanism for needle valves and other valves.

Conventionally, in two-dollar valves, plate valves, plug valves, and other valves that are installed in locations with a lot of vibration, for example, the valve stem may rotate naturally due to vibration.

If the valve stem were to rotate, the preset valve opening would change and the flow rate would fluctuate, potentially causing a major accident.

For this reason, conventional valves were not equipped with a special valve stem locking mechanism, so it was common practice to forcefully tighten the seal retainer, such as a seal retainer nut, to force the seal against the valve stem. was.

By doing so, it is possible to prevent the valve stem from rotating naturally due to vibration or the like.

However, with the above method, the gasket remains firmly attached to the valve stem, so when opening/closing the valve, the rotation of the valve stem becomes extremely heavy, making it difficult to operate the valve easily. .

Furthermore, although it is not a valve, a technique disclosed in Japanese Utility Model Publication No. 13-7389, for example, is known as a means for fixing a telescopic tube.

In this method, a notch (split groove) is cut at the tip of the outer tube, and a male screw is carved on the outer surface of the outer tube, and a nut with a tapered female screw is screwed into the male screw of the elastic tip. The inner tube inserted into the outer tube is clamped and fixed by tightening the same nut.

In other words, the distal end of the outer tube is deformed so as to be constricted, and the inner surface of the innermost tip comes into contact with and clamps the inner tube.

However, in this configuration, there is very little contact between the inner tube and the outer tube, so if the nut is tightened loosely, the clamping force will be small, and if it is tightened too tightly, the innermost tip of the outer tube will be damaged. There was a high risk that the rubber would dig into the outer surface of the inner tube and cause damage to the inner tube or breakage of the elastic tip end of the outer tube.

In other words, there was a problem in that the clamping force of the nut varied drastically depending on how tightly the nut was tightened.

Therefore, such a fixing means could not be used as a valve stem locking mechanism.

This is because valves installed in areas with a lot of vibration are subjected to continuous and complex vibrations, so the valve stem must be locked securely, and the valve stem must not be damaged. It is from.

The valve stem moves up and down each time the valve is opened and closed, and is always in sliding contact with the packing inside the stuffing box, so if the valve stem gets scratched, the sealing effect will deteriorate and the packing can also be damaged. This is because it will be put away.

This invention was devised in order to solve the problem of sloping.The purpose of this invention is to be able to securely and easily fix the valve stem in any position, and to prevent damage to the valve stem. To provide a valve stem locking mechanism for a valve which is compact and has a relatively simple structure, without having to attach a seal, and which can be used by partially improving a packing presser body.

The present invention forms a recess in which a female screw 9 having a diameter larger than that of the valve rod 2 is screwed in the upper part of the valve stem insertion hole 10, and the diameter of the female screw 9 is gradually reduced downward on the bottom surface of the recess to form the valve rod insertion hole. 10 is formed, and the valve stem 2 is inserted through the valve cover body 1.
A male screw 12 is screwed onto the outer periphery of the cylinder portion in which the valve stem insertion hole 13 is formed, and a bundle 7 is provided above the seal holder 5, and the diameter of the lower part of the valve stem insertion hole 13 is enlarged. A grip ring housing vagina is formed, and an inclined surface S is formed on the upper surface of the grip ring housing vagina, the diameter of which decreases upward in sequence and continues to the valve rod insertion hole 13, through which the valve rod 2 is inserted and A locking nut T screwed onto the female screw 9 of the presser body; a single groove 11 extending from the upper end to the lower end is formed on the peripheral wall of the cylinder, and the upper end surface thereof conforms to the inclined surface S of the locking nut 7. The valve stem 2 is inserted through the valve stem 2 to accommodate the grip ring of the locking nut 7. The basic structure of the invention is a grip ring 8 that can be inserted into and can be expanded or contracted in diameter.

Moreover, since the structure is as described above, the packing presser body 5
By tightening the locking nut 7 screwed into the female thread 9 of the valve stem 2, the grip ring 8 inserted into the valve stem 2 is deformed into a reduced diameter state without any force, and the valve stem 2 is firmly held on its entire inner circumferential surface. be grasped.

As a result, the valve stem will not be damaged at all, and the valve stem can be extremely firmly fixed in a desired position without replacing the grip ring.

Hereinafter, the structure, operation, and effects of the present invention will be explained with reference to drawings showing examples.

FIG. 1 is a longitudinal sectional front view showing a valve stem locking mechanism of a valve according to an embodiment of the present invention.

The figure shows a part of a needle valve, etc. A valve box (not shown) is attached below the valve cover body 1, and a valve body (not shown) provided in the valve body is attached to the lower end of the valve stem 2. (not shown) is fixed.

On the other hand, a bundle (not shown) is attached to the upper end of the valve stem 2, and the valve body is moved up and down by rotating the bundle.

Normally, a valve rod 2 is loosely fitted in the vertical direction inside the valve cover body 1.

A female thread is provided inside the lower part, and a matching male thread is carved into the valve stem 2, so that the valve stem 2 moves up and down while spiraling as the bundle rotates. It has become.

A gasket accommodating vagina is formed inside the upper part of the valve cover body 1 from its upper end, and a gasket 3 is housed in this vagina to seal between the valve cover body 1 and the valve stem 2. A packing retainer 4 is provided on the top, and this is provided with a valve stem insertion hole in the vertical direction, and is fitted onto the valve stem 2 to press down the seal 3 from above.

The seal presser 4 is further pushed in from above by a seal presser nut 5, which is a seal presser.

In this embodiment, a so-called packing holding nut 5 that is screwed onto a male screw formed on the upper outer periphery of the valve cover body 1 is used as the packing holding body, but the valve cover body 1 (or It goes without saying that a flange-type packing retainer that is fixed to the valve body may also be used.

Another lock nut 6 is first screwed into the male screw of the valve cover body 1, and by bringing this into contact with the seal retainer nut 5, the seal retainer nut 5 is fixed to the valve cover body 1. .

The configuration described above does not differ from a normal valve.

Next, the main parts of the present invention will be explained.

The valve stem locking mechanism of the present invention is characterized in that a part of the packing holding body, for example, the packing holding nut 5, is improved and a locking nut 7 and a gripping ring 8 are provided.

In this example, the packing retainer nut 5 has a concave portion coaxial with the valve stem insertion hole 10 and having a larger diameter than the valve stem insertion hole 10 formed in the upper part of the nut body as shown in FIG. In addition, the bottom surface of the recess is provided with an inclined surface T that gradually decreases in diameter as it goes downward and continues to the valve stem insertion hole 10.

The lower part of the packing nut 5 is a recessed part with a female screw, and the upper surface thereof is flat, and the upper surface of the packing holding nut 4 comes into contact with this and is pressed downward when the nut 5 is screwed in. become.

The locking nut 7 consists of a short cylindrical part in which a valve stem insertion hole 13 is formed and a bundle fixed to the upper part of the short cylindrical part, and a male screw threaded onto the female screw 9 above the packing nut 5 is provided on the outer periphery of the cylindrical part. A screw 12 is provided.

The lower part of the valve stem insertion hole 13 is expanded in diameter over a certain length from its lower end, thereby forming a grip ring receiving vagina having a diameter larger than that of the valve stem 2.

Further, on the innermost lower surface of the grip ring receiving vagina, an inclined surface S is formed which decreases in diameter as it goes upward and continues to the valve rod insertion hole 13.

The grip ring 8 is housed in the grip ring housing vagina of the locking nut 7, and has a cylindrical shape.

And on the peripheral wall, there is a groove 1 running from the top to the bottom.
1 has been cut out, forming a so-called side ring shape.

The upper end surface of the grip ring 8 is provided with an inclined surface S of the locking nut 7.
An inclined surface S' corresponding to the inclined surface S' is formed on the lower end surface, and an inclined surface T' corresponding to the inclined surface T of the packing retaining nut 5 is formed on the lower end surface.

The inner surface of the grip ring 8 is a smooth surface, and the grooves 11 are not limited to the diagonal direction as shown in FIGS. 2 and 3, but may be provided in the vertical direction.

The grip ring 8 can expand and contract in diameter due to the presence of the groove 11.

Since the present invention has such a configuration, the operation will be explained next.

When the bundle of the locking nut 7 is grasped and rotated to tighten it, the slope S of the locking nut I and the slope T of the seal retaining nut 5 come close to each other, and the grip ring 8 interposed between them approaches each other. Inclined surfaces S' corresponding to the inclined surfaces S and T, respectively, are provided on the upper and lower end surfaces.

Since it is provided with T' and the split groove 11, it is deformed into a reduced diameter state.

Then, since the valve stem 2 exists within this area, it is grasped strongly and in a wide area.

Therefore, the valve stem 2 is strongly fixed in that position and will not rotate naturally due to vibrations or the like.

Of course, the grip ring 8 is attached to the packing retainer nut 5 via the inclined surface.
Since it is firmly fixed by the locking nut 7, it will not rotate.

Since the present invention has the above-mentioned structure, the valve stem of the valve can be securely and easily fixed at the desired position, and even if it is used in a place where vibrations and shocks are often applied, the opening degree of the valve can be maintained. Appropriate flow rate can be maintained without fluctuation.

Since the inner surface of the grip ring is a cylindrical smooth surface, it uniformly contacts the outer peripheral surface of the valve stem and does not damage the valve stem.

Since the gripping ring has a groove provided on its outer circumferential wall to impart elastic force in the radial direction, it can withstand repeated use, and there is no need to replace it every time the valve is opened or closed.

In particular, if the groove is cut diagonally, it will not get caught on the outer peripheral surface of the valve stem and can be gripped smoothly.

Since the present invention utilizes a partially modified packing nut, the structure can be made compact and simple, and it can be easily applied to existing valves.

The present invention has excellent practical effects as described above.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional front view showing a valve stem locking mechanism of a valve according to an embodiment of the present invention, FIG. 2 is a plan view of a grip ring, and FIG.
FIG. 1 is the valve cover body, 2 is the valve stem, 3 is the seal, 4 is the seal holder, 5 is the seal holder nut, 7 is the locking nut, 8
is a grip ring, 9 is a female screw, 10 is a valve stem insertion hole, 11 is a split groove, 12 is a male screw, 13 is a valve stem insertion hole, T, T', S, S
' is a slope.

Claims (1)

[Scope of utility model registration request] A recess into which a female screw 9 having a diameter larger than that of the valve rod 2 is screwed is formed in the upper part of the valve stem insertion hole 10, and the diameter of the female screw 9, which is larger than that of the valve stem 2, is screwed into the bottom of the recess, and the diameter is gradually reduced downward to form the valve stem insertion hole No. 10 ζ. A gasket retainer is formed by forming a continuous inclined surface T, and is fixed to the valve cover body 1 through which the valve rod 2 is inserted; and a male screw 12 is screwed into the outer periphery of the cylindrical portion in which the valve rod insertion hole 13 is formed. A handle 7 is provided above the valve stem insertion hole 13, and the lower part of the valve stem insertion hole 13 is expanded in diameter to form a grip ring housing vagina, and the valve stem is inserted into the upper surface of the grip ring housing vagina by sequentially reducing the diameter upward. a locking nut 7 formed with an inclined surface S continuing to the hole 13, through which the valve stem 2 is inserted and screwed onto the female thread 9 of the packing retainer; A groove 11 is formed, and an inclined surface S matching the inclined surface S of the locking nut 7 is formed on the upper end surface of the groove 11.
', and an inclined surface T' that matches the inclined surface T of the packing presser is formed on the lower end surface, and the valve stem 2 is inserted into the holding ring housing vagina of the locking nut 7. A valve stem locking mechanism consisting of a grip ring 8 whose diameter can be expanded or contracted.