JPS5916598Y2 - Shaft sealing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a shaft sealing device used in fluid equipment such as valves and pumps, and more particularly to a shaft sealing device for a rotating shaft that is loaded with a packing to seal fluid.

Conventional shaft sealing devices for rotating shafts use packing such as gland packing made of braided fibers impregnated with lubricant to seal the shaft of fluid equipment, that is, the space between the casing of the equipment and the shaft. There is one that is loaded into the holder and tightened with a packing holder.

The packing used in such a shaft sealing device is usually loaded into the shaft sealing part of a fluid device by winding multiple packings of one type or a long set of packing multiple times along the shaft. .

There are various types of gaskets used in this shaft sealing device depending on the purpose of use, and they also have the following drawbacks.

■ Packing made mainly of high-grade asbestos is used as the packing for high-temperature valves, but it is difficult to absorb the stress relaxation caused by dedication at high temperatures.

■ Packings with high plasticity, such as lead foil packings or graphite packings, have poor restoring elasticity required for the packing.

■ Packings with a large thermal expansion coefficient, such as fluororesin packings or packings impregnated with fluororesin, have large thermal expansion at high temperatures and large thermal contractions at low temperatures, which have an undesirable effect on sealing properties.

Therefore, the present invention solves the above-mentioned conventional drawbacks at once by combining a conventional packing and a special elastic body, and creates a shaft sealing device for a rotating shaft that properly maintains and compensates for the sealing performance. This is what we are trying to provide.

That is, the present invention provides a shaft sealing device that seals fluid by sequentially loading and arranging a plurality of gaskets into the shaft sealing portion of a fluid device.
By replacing at least one of the plurality of packings to be loaded with an elastic body mainly composed of a fine metal wire entangled structure, the plurality of packings and the elastic body mainly consisting of a fine metal wire entangled structure can be replaced. The gist of this invention is a shaft sealing device for a rotating shaft which is arranged in combination.

Hereinafter, one embodiment of the present invention will be described in detail based on the drawings.

FIG. 1 shows an example of a shaft sealing device for a rotating shaft according to the present invention, in which 1 is a shaft, particularly the rotating shaft, 2 is a device casing, and a device loaded between the shaft 1 and the device casing 2. A conventional packing 3 and an elastic body 4 are used in combination, and are tightened with a packing presser 5.

FIG. 2 is an enlarged sectional view of the elastic body 4 shown in FIG. 1.

Further, FIGS. 3 and 4 are sectional views of elastic bodies 4' and 4'' showing other embodiments of the elastic body 4.

These elastic bodies 4, 4' consist of metal fine wire intertwined structures 6, 6', coatings 7, 7', and surface treatment films 8, 8', or, like the elastic body 4'', metal fine wires are used. It consists only of intertwined structures 6''.

These intertwined metal wire structures 6, 6' and 6'' are intertwined structures (me
ntal mesh) is placed in a mold and compression molded into the desired shape.

Therefore, by changing the compression molding conditions, the elastic force of the metal fine wire entangled structures 6, 6', 6'' itself can be strengthened or weakened.

In other words, if only the metal fine wire entangled structures 6, 6' are used as elastic bodies in combination with various conventional packings 3, the desired elastic force can be provided according to the characteristics of the conventional packings 3. , an extremely excellent shaft sealing device can be obtained.

Furthermore, in order to make the elastic body itself function as a packing, it can be braided with asbestos yarn, organic fiber, etc., or wrapped with lead foil, etc., so as to surround the intertwined metal wire structures 6, 6'. Covering bodies 7, 7' are formed.

Furthermore, if necessary, a surface treatment film 8, 8' such as an anti-friction agent may be provided on the coatings 7, 7'.

By using the elastic bodies 4, 4', and 4'' constructed in this manner in combination with the conventional packing 3 as shown in FIG. 1, an extremely excellent shaft sealing function was achieved as follows.

■ With packing made mainly of high-grade asbestos, stress relaxation occurs due to the hard work of the packing materials at high temperatures, and it was necessary to increase the frame size to absorb this stress. I was able to make up for it with my body.

■ Packaging with high plasticity has poor restoring elasticity,
Particularly when applied to rotating shafts, handling was difficult.

However, the elastic body can provide restoring elastic force, making handling easier.

There was also a problem with followability when the shaft runout was large, but
This problem was solved by combining it with an elastic body.

■ With a packing having a large coefficient of thermal expansion, phenomena such as extremely excessive packing surface pressure due to thermal expansion at high temperatures or increased fluid leakage from the packing due to thermal contraction at low temperatures can be eliminated at once.

As described above, the shaft sealing device for a rotating shaft according to the present invention can exhibit an excellent shaft sealing function, and can also eliminate the fatal drawbacks of the conventional shaft sealing device.

That is, in the field where this type of shaft sealing device is assembled, conventionally, the worker who handles the shaft sealing device requires a certain level of skill, and it has been impossible to eliminate differences in the performance of the shaft sealing device due to individual differences.

This is due to subtle effects such as how the packing is loaded onto the device and how tightly the packing is tightened.

However, the present invention eliminates and compensates for these drawbacks by creating a shaft sealing device that combines a conventional packing and an elastic body mainly composed of a fine metal wire intertwined structure.

In other words, it was possible to eliminate differences in the performance of the shaft sealing device due to individual differences, and also to eliminate the need for work by skilled workers.

Furthermore, even more important than what has been mentioned above, the structure of the present invention is capable of relieving the stress generated in multiple loaded packings, although the stress may vary in degree. This is a simple solution to the fatal drawback common to shaft seal devices.

In other words, in such a shaft sealing device, a plurality of loaded packings contact the outer circumferential surface of the rotating shaft and the inner circumferential wall of the equipment casing and press against the fluid pressure to be sealed, thereby sealing the fluid. ing.

Therefore, it is essential to maintain a predetermined stress generated in multiple packings, but when used for dynamic parts such as rotational movement, stress relaxation of the packings may occur due to the various causes mentioned above. The present invention also has the advantage of being able to eliminate such drawbacks.

As described in detail above, the present invention eliminates and compensates for the drawbacks of the conventional technology, and also facilitates handling, making a great contribution to industry.

[Brief explanation of the drawing]

Figure 1 is a schematic sectional view of the shaft sealing device according to the present invention, Figure 2 is an enlarged sectional view of the elastic body shown in Figure 1, and Figures 3 and 4 are the same as shown in Figure 1. FIG. 7 is an enlarged sectional view showing another aspect of the elastic body. 1... shaft, 2... equipment casing, 3
...Patsukin, 4, 4', 4"...
・Elastic body, 5... Packing presser, 6, 6',
6″...Metal fine wire entangled structure, 7,7′...
...Covering body, 8゜8' ...Surface treatment film.

Claims (1)

[Scope of utility model registration request] In a shaft sealing device that seals fluid by sequentially loading and disposing a plurality of packings into the shaft sealing part of a fluid device, one of the plurality of packings loaded has an elastic structure mainly composed of a metal wire entangled structure. A shaft sealing device for a rotating shaft in which a plurality of packings and an elastic body mainly composed of a fine metal wire entangled structure are arranged in combination.