JPH09324737A - Hydraulic machine shaft seal device - Google Patents

Abstract

(57) Abstract: A shaft sealing device for a hydraulic machine, which has an end face type shaft sealing structure, and a seal case constituting the shaft sealing device has stable followability for long-term use. The present invention provides a shaft sealing device capable of achieving stable sealing performance for a long period of time. SOLUTION: A porous member 9 having elasticity is arranged on the outer side of the seal case 4 and on the upper side of the O-ring 3 and on the inner side of the cover 11 so as to surround the gap on the inner side of the seal case 4. .

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an end face type ceramic shaft sealing device for preventing leakage of fluid from a main shaft portion of a hydraulic machine such as a water turbine and a pump.

[0002]

2. Description of the Related Art Generally, in a hydraulic machine such as a water turbine and a pump, as shown in FIG. 7, a casing 12 and a rotating member penetrating the casing 12 near an impeller (not shown) directly connected to a rotating shaft 1. A shaft sealing device is installed in order to prevent high-pressure muddy water from leaking from a gap formed with the shaft 1. Although there are various structures of the shaft seal device, an end face type shaft seal device is proposed in Japanese Utility Model Laid-Open No. 58-12678 and Japanese Patent Laid-Open No. 59-9367 for hydraulic machines. FIG. 7 shows JP-A-59
The shaft sealing device is disclosed in Japanese Patent Publication No. 9367. As shown in the figure, the shaft sealing device is located inside the casing 12 and the casing 12 that surrounds the outer periphery of the flange 8, and the seal case 4 that houses the seal ring 6, and the seal case 4
Attached to the cover 11 and provided on the surface facing the cover 11.
It is composed of a ring 3 and a coil spring 2 that presses the seal case 4.

In the shaft sealing device thus constructed, the high pressure fluid is sealed by the seal ring 6 pressed against the surface of the flange 8 and the O ring 3 attached to the seal case 4.

Water leaking in this structure flows in the direction of the arrow in the figure. The leaked water contains foreign matter that has passed through the gap between the sealing surfaces. Therefore, foreign matter enters and accumulates in the gap formed on the outer peripheral side of the seal case 4 above the O-ring and on the inner peripheral side of the cover 11. If not operated for a long period of time, accumulated foreign matter will dry and harden. Further, the facing surface of the O-ring 3 is also dried, the frictional force of the O-ring 3 increases during sliding, and the movement of the seal case 4 becomes poor.

[0005]

SUMMARY OF THE INVENTION Therefore, Japanese Patent Application Laid-Open No. 59-59
In the shaft sealing device as disclosed in Japanese Patent Publication No. 9367, the vertical movement of the seal case 4 is restricted by the dried deposit,
There is a drawback that the followability with respect to the movement of the main shaft 1 becomes poor and stable sealing performance cannot be obtained. Therefore, it is conceivable to install a closed container to prevent the entry of foreign matter, but if a closed container is attached to prevent the pressure from escaping, the O-ring 3
If the water is damaged and the high-pressure water leaks, the high-pressure water sprinkles on the upper surface of the seal case 4 and strongly presses the seal case 4, which may cause the seal ring to burn. On the other hand, in Japanese Unexamined Patent Publication No. 2-154869, a shielding plate is provided above the seal case 4 to prevent foreign matter from entering, but since foreign matter accumulates on the shielding plate, the accumulated foreign matter becomes an unbalanced weight. A moment force acts on the seal case 4, and the seal surface may be partially contacted and damaged.

An object of the present invention is to provide a shaft sealing device for a hydraulic machine, in which the seal case 4 constituting the shaft sealing device shows stable followability for long-term use, and stable sealing performance can be obtained for a long period of time. To provide.

[0007]

In order to achieve the above object, in the present invention, foreign matter is prevented from entering a gap formed on the outer peripheral side of the seal case above the O-ring and on the inner peripheral side of the cover. In addition, a means for holding the lubricating water was constructed.

That is, a case 5b having a flange 8 on a main shaft 1 and a seat ring 7 stored in the flange 8 is fixed, a pump casing 12a is attached so as to surround the main shaft 1 and the flange 8, and a pump casing 12a is formed. A cover 11 and a case 5a fitted with a seal ring 6 and a seal case 4 fitted with an O-ring 3 are arranged in a gap defined by the main shaft 1, and the seal ring 6 is pressed against the surface of the seat ring 7 to prevent fluid flow. This is an end face type shaft seal device that prevents leakage.
A shaft sealing device for a hydraulic machine, comprising a seal case 4 and an elastic porous member 9 arranged on the upper part of the cover 11 so as to surround a gap formed on the upper part of the cover 11 and on the inner peripheral side of the cover 11. .

In the shaft sealing device of the present invention, since the porous member 9 having elasticity fulfills the function of the filter, it is formed on the outer peripheral side of the seal case 4 on the upper side of the O-ring 3 and on the inner peripheral side of the cover 11. Foreign matter does not enter and accumulate in the gap. Further, since the porous member 9 having elasticity has water retention property,
It functions as lubricating water for the ring 3 and stable sliding is obtained. Therefore, the seal case 4 follows the movement of the flange 8 well, and stable sealing performance can be obtained for a long period of time. on the other hand,
Water is automatically supplied to the porous member 9 having elasticity when water leaks. Since the lubricating water once stored has a small evaporation area, it hardly evaporates and is retained for a long time. Therefore, stable performance for a long time can be obtained without supplying water from the outside.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. The shaft sealing device for a pump according to the embodiment of the present invention is
A pump shaft sealing device (hereinafter referred to as a ceramic shaft sealing device) in which a sealing material is made of ceramics, which is mounted on a drainage pump. That is, in the embodiment of the present invention, ceramics was used as the sealing material for the pump shaft sealing device, but the sealing material is not limited to ceramics.

FIG. 1 is a vertical sectional view of a shaft sealing device according to an embodiment of the present invention. In the figure, a shaft seal device 16 is a device for preventing fluid from leaking from a gap between the main shaft 1 and the pump casing 12a, and a flange 8 fixed to the main shaft 1 and a seat ring 7 housed and fixed on an upper surface of the flange 8. The case 5b is fixed, the seal ring 6 is pressed against the seat ring 7,
The seal ring 6 is housed in the case 5a so that it can be attached to and detached from the seal case 4, and is fixed by a bolt (not shown). A pump casing 12a is attached so as to surround the main shaft 1 and the flange 8, a cover 11 is attached to the pump casing 12a, and an O-ring 3 that seals a gap between the seal case 4 and the cover 11 is provided. Also,
A coil spring 2 is provided to press the seal ring 6 against the seat ring 7. And the seal case 4
A means for preventing foreign matter from entering the gap formed on the outer peripheral side of the O-ring 3 on the upper side of the O-ring 3 and on the inner peripheral side of the cover 11 and holding the lubricating water is constituted.

That is, the porous member 9 having elasticity is provided on the upper portion of the seal case 4 and the cover 11 so as to surround the gap formed on the outer peripheral side of the seal case 4 on the upper side of the O-ring 3 and on the inner peripheral side of the cover 11. I placed it. The lower surface of the porous member 9 having elasticity is closely fixed to the upper surface of the seal case 4 with an adhesive. The adhesive is preferably a room temperature curing type.
Here, the material of the seat ring 7 and the seal ring 6 is ceramics (silicon carbide).

In the shaft sealing device, when pumping water, the fluid passes from the outer peripheral side of the sealing surface to the inner peripheral side and leaks. Leaked fluid is spindle 1
The outer peripheral surface and the inner peripheral surface of the seal case 4 rise to reach the inner peripheral surface of the porous member 9 having elasticity. After that, it flows to the outer peripheral side on the upper surface of the positioning member 10 fixing the elastic porous member 9. Therefore, the sediment particles are also carried along with the leaked fluid, and the seal case 4
Foreign matter such as earth and sand does not accumulate in the gap formed on the outer peripheral side of the O-ring 3 and on the inner peripheral side of the cover 11. Since the porous member 9 having elasticity is easily deformed, the movement of the seal case 4 is not restricted at all, and stable movement can be obtained. When the pumping is completed, the water in the pump casing 12a falls, but is stored in the elastic porous member 9 during the pumping.

In the shaft sealing device of the present invention, since the porous member 9 having elasticity fulfills the function of the filter, it is formed on the outer peripheral side of the seal case 4 above the O-ring 3 and on the inner peripheral side of the cover 11. Foreign matter does not enter and accumulate in the gap. Moreover, since the porous member 9 having elasticity has water retention property, the pumped-up liquid stored therein functions as lubricating water for the O-ring 3, and stable sliding is obtained. In addition, it has been confirmed by experiments that the frictional force of the O-ring 3 is reduced by one digit when compared to the dry lubrication condition when the O-ring 3 is in the water lubrication state. Therefore, the seal case 4 follows the movement of the flange 8 well, and stable sealing performance can be obtained for a long period of time. On the other hand, the porous member 9 having elasticity is automatically supplied with water when water leaks. Since the lubricating water once stored has a small evaporation area, it hardly evaporates and is retained for a long time. Therefore, stable performance for a long time can be obtained without supplying water from the outside.

With the structure of the shaft sealing device as described above, since the porous member 9 having elasticity allows water to pass through well, even if the O-ring 3 is damaged and high-pressure water leaks out, the pressure is easily reduced and the seal case. 4 is not pressed by an abnormal force, and burnout is reliably prevented. In addition, the positioning member 10
Although foreign matter is deposited on the upper surface of the seal case 4, since it does not act as the pressing force of the seal case 4 at all, partial contact of the seal surface due to the moment force is eliminated and damage is surely prevented.

A second embodiment of the present invention will be described with reference to FIG. FIG. 2 is a vertical cross-sectional view of the shaft sealing device of this embodiment.
Although this embodiment is structurally almost the same as the first embodiment,
The difference is that in the present embodiment, lubricating grease 13 is filled in a gap formed on the outer peripheral side of the seal case 4 on the upper side of the O-ring 3 and the inner peripheral side of the cover 11, and further, the seal case 4 and the cover 11 are provided. That is, the porous member 9 having elasticity is arranged on the upper part of the. Here, since the grease 13 is used as the lubricant of the O-ring 3, the viscosity is higher than that of water and the frictional force can be reduced.

A third embodiment of the present invention will be described with reference to FIG. FIG. 3 is a vertical cross-sectional view of the shaft sealing device of this embodiment.
Although this embodiment is structurally almost the same as the second embodiment,
The difference is that in the present embodiment, lubricating grease 13 is filled in a gap formed on the outer peripheral side of the seal case 4 on the upper and lower sides of the O-ring 3 and on the inner peripheral side of the cover 11, and the upper part of the O-ring 3 is sealed. That is, the porous member 9 having elasticity is arranged on both the lower part and the lower part. With such a configuration, the lubricating action of the O-ring portion is improved, and the followability of the seal case is reliably maintained for a long time.

A fourth embodiment of the present invention will be described with reference to FIG. FIG. 4 is a vertical cross-sectional view of the shaft sealing device of this embodiment.
Although this embodiment is structurally almost the same as the first embodiment,
The difference is that in the present embodiment, the elasticity arranged in the upper part of the seal case 4 and the upper part of the cover 11 so as to surround the gap formed on the outer peripheral side of the seal case 4 on the upper side of the O-ring 3 and on the inner peripheral side of the cover 11. That is, the circumferential groove 14 is provided on the lower surface side of the porous member 9 that is provided.

With such a structure, the deformation force against the vertical movement of the seal case is effectively suppressed.

A fifth embodiment of the present invention will be described with reference to FIG. FIG. 5 is a vertical cross-sectional view of the shaft sealing device of this embodiment.
Although this embodiment is structurally almost the same as the second embodiment,
The difference is that in the present embodiment, the elasticity arranged in the upper part of the seal case 4 and the upper part of the cover 11 so as to surround the gap formed on the outer peripheral side of the seal case 4 on the upper side of the O-ring 3 and on the inner peripheral side of the cover 11. That is, the porous member 9 has a two-layer structure of coarse and dense 9a and 9b in the thickness direction.

As described above, the porous member has a two-layer structure of coarse and dense in the thickness direction, and the dense layer side is installed on the O-ring side,
Lubricating water can be collected on the O-ring side of the dense layer side, which has the effect of reducing evaporation loss.

A sixth embodiment of the present invention will be described with reference to FIG. FIG. 6 is a vertical cross-sectional view of the shaft sealing device of this embodiment.
Although this embodiment is structurally almost the same as the second embodiment,
The difference is that in the present embodiment, the elasticity arranged in the upper part of the seal case 4 and the upper part of the cover 11 so as to surround the gap formed on the outer peripheral side of the seal case 4 on the upper side of the O-ring 3 and on the inner peripheral side of the cover 11. Positioning member 1 for porous member 9
0a is a steel plate having innumerable holes 10b.

With this structure, the effect of supplying water to the porous member can be obtained, so that the water retaining function can be maintained for a long time, and the followability of the seal case 4 is stabilized.

An eighth embodiment of the present invention will be described with reference to FIG. FIG. 8 is a sectional view showing the configuration of a drainage pump equipped with the shaft sealing device of this embodiment. The drainage pump is a transmission 15
It is composed of a main shaft 1 driven via a blade, a blade 17 fixed to the lower end of the main shaft 1, and a shaft sealing device 16 mounted on the blade 17. The shaft sealing device 16 has substantially the same structural shape as that of the first embodiment.

Here, the construction of the drainage pump equipped with the shaft seal device of the present embodiment is shown in a sectional view, but the construction is almost the same in the case of a water turbine.

In the embodiment of the present invention, ceramics are used as the seal ring and the seat ring material, but both are made of a high hardness material such as cemented carbide, or one is made of a high hardness material such as cemented carbide. Even when a combination of cemented carbide and ceramics is used, the same effect can be obtained.

In the above description, the case of using ceramics as the sealing material of the shaft sealing device has been described (ceramic sealing material is most suitable, of course).
However, it is needless to say that the sealing material is not limited to the case where the sealing material is ceramics, and other materials may be used.

According to this embodiment, the following effects can be obtained.
That is, (1) since the elastic porous member functions as a filter, foreign matter is prevented from invading and accumulating in the gap formed on the outer peripheral side of the seal case on the upper side of the O-ring and on the inner peripheral side of the cover. Further, since the porous member has water retention property, it functions as lubricating water for the O-ring, and stable sliding can be obtained. Therefore, the followability of the seal case is improved, and stable sealing performance is exhibited for a long period of time.

(2) Since the porous member having elasticity allows water to pass through well, even if the O-ring is damaged and high-pressure water leaks, the pressure is not easily lowered and the seal case is not pressed by an abnormal force. Burnout of the seal ring can be reliably prevented.

(3) Foreign matter is deposited on the upper surface of the positioning member, but since it does not act as the pressing force of the seal case at all, it is possible to prevent uneven contact of the seal surface due to moment force.

[0031]

According to the present invention, since the seal case constituting the shaft sealing device exhibits good followability, stable sealing performance can be obtained for long-term use.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of a shaft sealing device for a hydraulic machine according to the present invention.

FIG. 2 is a sectional view showing a second embodiment of the shaft sealing device for a hydraulic machine according to the present invention.

FIG. 3 is a cross-sectional view showing a third embodiment of the shaft sealing device for a hydraulic machine of the present invention.

FIG. 4 is a sectional view showing a fourth embodiment of the shaft sealing device for a hydraulic machine according to the present invention.

FIG. 5 is a sectional view showing a fifth embodiment of the shaft sealing device for a hydraulic machine according to the present invention.

FIG. 6 is a sectional view showing a sixth embodiment of the shaft sealing device for a hydraulic machine of the present invention.

FIG. 7 is a cross-sectional view showing an embodiment of a conventional shaft sealing device for a hydraulic machine.

FIG. 8 is a cross-sectional view showing a drainage pump including a conventional drainage pump shaft sealing device.

[Explanation of symbols]

1 ... Spindle, 2 ... Coil spring, 3 ... O-ring, 4 ... Seal case, 5a, 5b ... Case, 6 ... Seal ring, 7 ...
Seat ring, 8 ... Flange, 9 ... Porous member, 10 ...
Positioning member, 12a ... Pump casing.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shigenobu Nagasawa 603 Kitsudachi-cho, Tsuchiura-shi, Ibaraki Hitate Works Tsuchiura Plant

Claims (8)

[Claims] 1. A main shaft has a flange, and a case in which a seat ring is stored is fixed to the flange, and a pump casing is attached so as to surround the main shaft and the flange. The pump casing and the main shaft are configured. An end face type shaft sealing device for arranging a cover, a case with a seal ring and a seal case with an O ring attached in a gap, and pressing the seal ring against the seat ring surface to prevent fluid leakage, A shaft seal for a hydraulic machine, comprising means for preventing foreign matter from entering a gap formed on the outer peripheral side of the seal case on the upper side of the O-ring and on the inner peripheral side of the cover to retain lubricating water. apparatus. 2. The means for preventing foreign matter from entering the gap formed on the outer peripheral side of the seal case on the outer peripheral side of the seal case and on the inner peripheral side of the cover, and holding the lubricating water. A shaft sealing device for a hydraulic machine, comprising a porous member having elasticity arranged above the seal case and the cover so as to surround a gap. 3. A main shaft has a flange, and a case in which a seat ring is stored is fixed to the flange, and a pump casing is attached so as to surround the main shaft and the flange. The pump casing and the main shaft are configured. An end face type shaft sealing device for arranging a cover, a case with a seal ring and a seal case with an O ring attached in a gap, and pressing the seal ring against the seat ring surface to prevent fluid leakage, A lubricant is put in a gap formed on the outer peripheral side of the seal case on the upper side of the O-ring and on the inner peripheral side of the cover, and the elastic porous material is arranged on the upper side of the seal case and the cover so as to surround the gap. A shaft sealing device for a hydraulic machine, which is configured by members. 4. A main shaft has a flange, and a case containing a seat ring is fixed to the flange, and a pump casing is attached so as to surround the main shaft and the flange. The pump casing and the main shaft are configured. An end face type shaft sealing device for arranging a cover, a case with a seal ring and a seal case with an O ring attached in a gap, and pressing the seal ring against the seat ring surface to prevent fluid leakage, A shaft sealing device for a hydraulic machine, wherein a porous member having elasticity is arranged so as to surround the O-ring on the outer peripheral side of the seal case and the inner peripheral side of the cover. 5. A shaft sealing device for a hydraulic machine according to claim 2, 3 or 4, wherein the elastic porous member has a coarse and dense two-layer structure. 6. The shaft sealing device for a hydraulic machine according to claim 2, 3 or 4, wherein a groove is provided in a circumferential direction on a lower surface side of the elastic porous member. 7. A drainage pump equipped with the shaft sealing device for a hydraulic machine according to claim 1, 2, 3, 4, 5 or 6. 8. A water turbine equipped with the shaft sealing device for a hydraulic machine according to any one of claims 1, 2, 3, 4, 5 and 6.