JPH0533829Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Field of Industrial Application) The present invention relates to a shaft sealing device for a valve in which a drive mechanism is directly mounted on the shaft mounting part of a valve body. This invention relates to an improvement in a shaft sealing device that can easily retighten a gland packing attached to a shaft mounting part of a valve or the like.

(Prior Art) For example, a conventional shaft seal device in which a drive mechanism is directly mounted on a ball valve is as shown in FIG.
A hollow rectangular bracket 3 having openings for insertion of tools on both sides is screwed onto the mounting flange 2 of the valve body 1 with bolts, nuts, etc., and a drive mechanism 4 is fixed on the upper part of the rectangular bracket 3. The drive shaft 4a of the drive mechanism 4 and the stem 5 of the valve are connected by a connector 6, while a gland flange 7 into which the stem 5 is fitted is arranged inside the bracket 3, and the gland flange 7 and the valve body are connected. Two left and right bolts 8 are inserted between the flanges 2 of 1, respectively, and tightened with nuts 9.

Then, by inserting a tool through the opening of the bracket 3 and tightening the nuts 9 screwed onto each bolt 8, the gland flange 7 is tightened.
The gland packing 10 attached to the stem 5 can be further tightened by lowering the gland in a straight line.

(Problem to be solved by the invention) However, in the conventional shaft seal device described above, two left and right bolts 8 are screwed between the gland flange 7 and the mounting flange 2 of the valve body 1. Since the gland packing 10 is retightened by individually tightening the nuts 9 against the two bolts 8, the gland flange 7 itself naturally becomes larger in the left and right direction. The bracket 3 in which the gland flange 7 is placed also becomes larger accordingly, and ultimately the shaft sealing device itself becomes unnecessarily large, which is a major problem that goes against the current demands for miniaturization. At the same time, there is a problem in that the number of parts required for retightening inevitably increases.

In addition, when retightening the gland packing 10, the nuts 9 must be tightened individually for the left and right bolts 8, which not only requires the tightening work twice, but also requires equal tightening on the left and right sides to ensure uniformity. Since proper retightening cannot be obtained, the conventional method also has the problem that the retightening work is very complicated.

(Means for Solving the Problems) Therefore, the present invention was developed to effectively solve the problems of the conventional shaft sealing device, and the present invention has been developed to effectively solve the problems of the conventional shaft seal device. A storage chamber for storing the gland packing is formed inside the storage chamber, and a threaded surface is formed above the inner wall defining this storage chamber, and a screw surface of the storage chamber is formed on the outer peripheral surface of the lower part of the gland externally fitted on the stem. In addition to forming a threaded portion that engages with the surface, an operating flange that can be rotated is formed on the top of the gland, and the gland can be retightened by rotating the gland via this operating flange. Further, the lower surface of the bracket formed in a cross-sectional shape is placed on the upper surface of the flange provided at the upper end of the shafting part of the body, and the flange and the bracket are connected with bolts and nuts. Fix the drive mechanism placed on the top surface with the bolts mentioned above, position the operating flange of the gland mentioned above in the horizontal opening of the bracket, insert tools through this opening, and rotate the operating flange. configured so that it is possible.

(Function) Although the present invention uses a bracket as in the past, the bracket of the present invention has a cross-sectional shape placed on the flange and fixed with bolts. There is no bottom part of the bracket, which makes it more compact.Moreover, the gland disposed inside the bracket has a threaded part on the lower part that threads into the threaded surface of the storage chamber, and an operating collar part on the upper part that can be rotated. Since it is arranged inside the bracket in a state where it is formed and screwed into the threaded surface of the shaft mounting part, it is much smaller than the conventional bolts and nuts that require it. This can greatly contribute to miniaturization and miniaturization of the entire device.

Moreover, with the present invention, the gland packing inside the storage chamber can always be retightened reliably by simply rotating the gland itself using the operating flange of the gland, which greatly simplifies the retightening work. At the same time, the number of parts can be reduced compared to the conventional method.

(Examples) Hereinafter, the present invention will be described in detail based on illustrative examples. Incidentally, the shaft sealing device according to each embodiment is applied to a ball valve, but is not limited to this, and the shaft sealing device according to each embodiment is applied to a 90° or 180° stem.
Needless to say, it can be easily applied to various valves that open and close with the rotation of the motor.

First, the shaft sealing device of the first embodiment will be explained.
As shown in the figure, a bracket 14 having openings 14a for inserting tools on both sides and having a gland (to be described later) arranged inside is integrally molded onto the shaft mounting portion 13 of the stem 12 provided on the valve body 11. The structure is such that a drive mechanism 17 having a built-in motor (not shown) or the like can be directly mounted on the upper part of the bracket 14 via bolts 15 and nuts 16.

In this embodiment, the shaft mounting portion 13
A storage chamber 19 for storing the gland packing 18 is formed inside the gland 2 , and a female screw surface 20 is formed on the inner wall defining the storage chamber 19 .
A male screw portion 2 screwed into the female screw surface 20 at the lower part of 1.
2, and a polygonal operating flange 23 that can be rotated is integrally formed on the upper part of the flange 2.
The structure is such that the gland packing 18 can be tightened simply by rotating the gland 21 inside the bracket 14 via the connector 3.

In addition, the reference numeral 24 in the figure indicates the stem 12 and the drive mechanism 17.
In this embodiment, the stem 12 and the connector 24 are jointed with the uneven shape provided at each end, as shown in the figure. The present invention is not limited to this, and it is also possible to configure both 12 and 24 to be integrated and directly connected to the drive shaft of the drive mechanism 17 depending on the implementation. or,
Reference numeral 25 is a washer disposed on the lower surface of the gland packing 18, and 26 is a ring interposed between the connector 14 and the drive shaft of the drive mechanism 17.

Therefore, in the shaft sealing device of the first embodiment, as shown in FIGS. 2 and 3, the washer 25 and the gland are placed in the storage chamber 19 formed in the shaft mounting portion 13 of the stem 12. At the same time as storing the packing 18, insert the lower male screw part 22 of the gland 21 into the storage chamber 1.
After screwing into the female screw surface 20 of 9 and disposing the gland 21 inside the bracket 14, the stem 12 and the drive shaft of the drive mechanism 17 are connected via the connector 24, and the drive mechanism 17 is connected to the bolt. 15. If it is screwed onto the bracket 14 via the nut 16, the drive mechanism 17 will be directly mounted on the bracket 14.

In such a situation, if it becomes necessary to retighten the gland packing 18, insert the tip of a tool such as a spanner into the inside of the bracket 14 through the opening 14a, and tighten the tip of the tool. When the operating flange 23 of the gland 21 is rotated, the gland 21 rotates and descends due to the screw engagement between the female threaded surface 20 of the shaft mounting part 13 and its own male threaded part 22, and is installed in the storage chamber 19. Since the gland packing 18 that has been tightened is pressed, the gland packing 18 can be further tightened.

Moreover, such retightening work has to be done on both the left and right sides as in the past.
The gland packing 18 can be retightened by simply rotating the gland 21 without having to tighten the nuts individually against the main bolts. This not only simplifies the work, but also ensures uniform retightening at all times. It will be guaranteed.

Next, the shaft sealing device according to the second embodiment will be explained. The second embodiment is based on the above-mentioned first embodiment, but the differences are as shown in Fig. 4. The integrally molded bracket of the first embodiment is formed into a U-shaped cross section, and the lower surface of the bracket 14 is placed on the upper surface of the flange 27, making it a split type. When mounting the drive mechanism 17 on the upper surface of the bracket 14, the bracket 14 is connected to the flange 27 via bolts 15 and nuts 16, and the other configurations are the same as in the first embodiment. is exactly the same.

Therefore, in this second embodiment as well, not only can the drive mechanism 17 be directly mounted on the shaft mounting part 13 via the bracket 14, but also the gland packing 18 needs to be tightened more. In such a case, an opening 14a is provided inside the bracket 14.
When the tip of a tool is inserted and the gland 21 is rotated with the tip of the tool, the gland 21 connects with the female threaded surface 20 of the shaft mounting part 13 and its own male threaded part 22.
By screwing together, it descends while rotating and opens into storage chamber 1.
Since the gland packing 18 in the inner part 9 is pressed, the gland packing 18 can be further tightened.

Further, the split type bracket 14 of this embodiment has the advantage that it can be easily applied to existing valves having a mounting flange 27.

(Effects of the invention) As described above, the present invention has the following effects.

The gland itself is not only much smaller than conventional glands, but because the bottom surface of the bracket is in contact with the top surface of the flange, the height and width of the bracket opening can be kept compact to the minimum necessary size. This can greatly contribute to the miniaturization of the bracket and the overall device.

Furthermore, with the present invention, the gland packing inside the storage chamber can always be retightened reliably by simply rotating the gland itself using the operating flange of the gland, which greatly simplifies the retightening work. At the same time, it also offers the advantage of reducing the number of parts compared to the conventional method.

[Brief explanation of the drawing]

Fig. 1 is an exploded perspective view showing a ball valve with a drive mechanism equipped with a shaft sealing device according to a first embodiment of the present invention, Fig. 2 is a cross-sectional view showing the same assembled state, and Fig. 3 is a half-section of the same essential part. 4 is an exploded perspective view showing a ball valve with a drive mechanism equipped with a shaft sealing device according to a second embodiment, and FIG. 5 is a half-cut sectional view of a main part of a conventional ball valve with a drive mechanism. be. 11...Valve body, 12...Stem, 13
... shaft mounting part, 14 ... bracket, 14a ... insertion opening, 17 ... drive mechanism, 18 ... gland packing, 19 ... storage chamber, 20 ... female thread surface,
21...Gland, 22...Screw part, 23...Operation collar part (operation part).

Claims (1)

[Scope of utility model registration request] A storage chamber for storing the gland packing is formed inside the shaft mounting portion of the stem provided in the valve body, and a threaded surface is formed above the inner wall defining this storage chamber. A threaded portion that engages with the threaded surface of the storage chamber is formed on the outer circumferential surface of the lower part of the gland, and an operating collar portion that can be rotated is formed on the upper portion of the gland, and the gland is rotated through this operating collar portion. By moving the gland, the gland packing can be retightened.Furthermore, the lower surface of the bracket formed in a cross-sectional shape is placed on the upper surface of the flange provided at the upper end of the shafting part of the body, and the flange and bracket are tightened. At the same time, the drive mechanism placed on the top surface of the bracket is fixed with the bolts mentioned above, and the operation flange of the gland mentioned above is positioned in the horizontal opening of the bracket, and the operating flange of the gland mentioned above is placed in the opening in the horizontal direction of the bracket. A valve shaft sealing device characterized in that the operating flange is configured to be rotatable by inserting tools.