JPH051742Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) This invention relates to a sealing device suitable for use in, for example, a vertical pump.

(Prior Art) FIG. 3 shows a mechanical seal 100 as a conventional sealing device of this type. A rotating shaft 104 is inserted into the shaft hole 102 of the seal cover 101 . A seat ring 105 is fixed to the inner periphery of the seal cover 101. In addition, the rotation axis 1
The collar 10 is attached to the sleeve 106 fitted to the sleeve 04.
7. Spring 107a, compression ring 10
8. A driven ring 109 is attached. In this way, the driven ring 109, which rotates integrally with the rotating shaft 104, and the seat ring 105 are brought into close contact to form a shaft sealing portion A.

On the other hand, on the end surface side of the seal cover 101, a dust seal means 110 is provided to prevent dust such as dust and dirt from the outside 103 from entering the vicinity of the shaft seal portion A. This dust seal means 110 is
A ring-shaped seal member 114 includes a collar 112 fixed in a predetermined position on the sleeve 106 by a set screw 111, and a lip portion that slides on a plate 113 assembled to the end face of the seal cover 101.
It is composed of.

Note that 115 connects the sleeve 106 to the rotating shaft 104.
Retaining rings 116 and 117 are flushing holes and quenching holes formed in the seal cover 101.

Mechanical seal 10 configured as above
0 is attached to the device main body 101a in the following manner.

A collar 107, a spring 107a, a compression ring 108, and a driven ring 109 are attached to the sleeve 106 outside the device body 101a, while the seat ring 1 is attached to the seal cover 101.
Attach 05. Then, move the mechanical seal assembly on the sleeve 106 side and the seal cover 101 side to the device main body 101a side, and tighten the nut 118.
After tightening and positioning the sleeve 106 side assembly with respect to the rotating shaft 104, the retaining ring 115 is fixed by the set screw 115a. At this point, the seat ring 105 and the driven ring 109 are brought into close contact with each other under a predetermined pressure to form a shaft sealing portion A.

Thereafter, the collar 112 is slid along the sleeve 106, and the position is adjusted so that the lip portion of the seal member 114 comes into close contact with the plate 113 with a predetermined pressure, and the set screw 111 is tightened to complete fixing of the dust seal means 110. do.

(Problems to be Solved by the Invention) However, the above conventional example has the following problems.

The dust seal means 110 must be accurately positioned with respect to the seal cover 101, which is troublesome.

When the rotating shaft 104 rotates, the seal member 11
4 slides against the plate 113 and wears out,
Not only is the durability poor, but the abrasion powder may enter the shaft seal portion A, which may reduce the sealing performance of the shaft seal portion A.

To position the dust seal means 110,
Space must be secured for movement in the axial direction, which increases the size of the entire device.

When replacing the seal member 114, it must be pulled out from the shaft end side of the rotating shaft 104.
Work efficiency is poor.

This idea is to solve the above problem,
To provide a sealing device capable of preventing dust from entering a shaft sealing part without positioning a seal cover after fixing it to a device body, and equipped with dust sealing means having excellent durability. Another object of the present invention is to provide a sealing device that does not require space for movement in the axial direction, has a small size as a whole, and is equipped with a dust sealing means that can be replaced easily and quickly.

(Means for Solving the Problems) In order to achieve the above object, this invention provides a shaft that maintains fluid tightness between a seal cover fixed to the device body and a rotating shaft inserted into the shaft hole of this seal cover. In a sealing device in which a dust sealing means is provided on an end face side of a seal cover in order to form a sealing part and prevent dust outside the seal cover from entering the shaft sealing part, the dust sealing means is attached to the seal cover side. A split-shaped rotary seal member attached to the rotating shaft side so as not to come into contact with the fixed seal member in order to form a minute flow path between the split-shaped fixed seal member and the opposing surface of the fixed seal member. It is composed of the following.

(Function) In this invention based on the above configuration, a split fixed seal member and a split rotary seal member exist outside the seal cover in a non-contact state. A microchannel is formed between the opposing surfaces of the stationary seal member and the rotary seal member, which communicates the outside of the seal cover with the shaft seal portion.

(Example) Next, this invention will be explained based on an example shown in FIGS. 1 and 2.

Figure 1 shows mechanical seal 1 as a sealing device.
shows. A rotary shaft 6 is disposed in a main body 3a of a device such as a pump, extending from a shaft hole 4 of a seal cover 3 that is tightened and fixed with a nut 2 to an outside 5 thereof. On the inner periphery of the seal cover 3, a movable ring 7 that is movable in the axial direction is held by a drive pin 7a and is pressed by a spring 8 toward the device main body 3a. Reference numeral 9 denotes a driven ring made of carbon fixed to the end face of the movable ring 7. In addition,
3b and 3c are injection holes and extraction holes for circulating fluid.

The sleeve 10 fitted onto the rotating shaft 6 and fixed by the set screw 6a also includes a collar 12 fixed by the set screw 11, an auxiliary ring 14 connected to the collar 12 via a dowel pin 13, and a collar 12 fixed by the set screw 11. A fixed seat ring 15 is attached to the end face of the auxiliary ring 14. In this way, the seat ring 15, which rotates integrally with the rotating shaft 6 via the sleeve 10, collar 12, and auxiliary ring 14, and the aforementioned driven ring 9 are brought into close contact to form a shaft sealing portion E. . In addition, 16, 17, 18 are O
It's a ring.

On the other hand, a dust sealing means 19 is provided on the end surface side of the seal cover 3 to prevent dust such as dust and dirt from the outside 5 from entering the shaft sealing portion E side. This dust sealing means 19 includes a fixed sealing member 20 made of resin and a rotary sealing member 2 made of resin.
1. The fixed seal member 20 and the rotary seal member 21 are formed into a split shape that can be divided into two parts as shown in FIG. It is installed. The stationary seal member 20 and the rotary seal member 21 can be easily processed into split shapes by forming them into predetermined dimensions and shapes and then cutting them with a cutting tool. Further, the rotary seal member 21 is fixed by a screw member 25 to the outer periphery of an annular holder 24 fixed to the sleeve 10 by a set screw 23. Therefore, when the step portion 26 of the holder 24 comes into contact with the end surface of the sleeve 10, the rotary seal member 21
is designed to stop at a position close to the fixed seal member 20.

The fixed seal member 20 and the rotating seal member 21
is in a non-contact state, and a minute flow path F bent in a predetermined shape is formed between the opposing surfaces and between the seal cover 3 and the seal cover 3 . The outside 5 of the seal cover 3 and the shaft sealing portion E in the shaft hole 4 communicate with each other through this flow path F.

In FIG. 2, reference numeral 27 indicates an insertion hole provided in the rotary seal member 21, into which the screw member 25 is inserted.

In the mechanical seal 1 configured as described above, the shaft sealing portion E seals the sealing fluid sealed inside the device main body 3a. Also,
A dust sealing means 1 is provided on the outside 5 of the seal cover 3.
Since the flow path F is formed by the passage 9, dust such as dust and dirt does not easily enter the shaft sealing portion E.

On the other hand, a minute flow path F is formed by the fixed seal member 20 and the rotary seal member 21 attached via the holder 24. Therefore, there is no need to position the dust seal means 19 after the rotary seal member 21 is attached, and no space in the axial direction is required for positioning, so the entire device can be downsized.

In addition, the rotating seal member 21 and the fixed seal member 2
Since it is not in contact with 0, the rotating shaft 6
There is no wear of both during rotation, which not only improves the product life but also eliminates the risk of abrasion powder entering the shaft sealing portion E side and degrading the sealing performance. Furthermore, in the above embodiment, since the stationary seal member 20 and the rotary seal member 21 are both made of resin, even if they come into contact, sparks will not be generated or seizure will occur due to overheating. There is no need to worry.

When replacing the dust seal means 19, the screw member 25 is pulled out from the holder 24, the rotary seal member 21 is divided and removed, and the fixed seal member 20 is divided from the mounting groove 22 of the seal cover 3. All you have to do is remove it and install a new fixed seal member and a new rotary seal member.

Therefore, there is no need to move the dust seal means 19 to the end of the rotating shaft 6, and it can be replaced easily and quickly.

In this embodiment, a single mechanical seal having one shaft sealing portion in the shaft hole 4 has been described, but the present invention may also be applied to a double mechanical seal having two shaft sealing portions.

Furthermore, although the description has been made regarding a mechanical seal in which the sleeve 10 is fitted onto the rotating shaft 6, the present invention is also applicable to a mechanical seal without a sleeve.

Furthermore, although we have described a mechanical seal in which the seat ring rotates integrally with the rotating shaft and the driven ring does not rotate, there is also a configuration in which the driven ring rotates integrally with the rotating shaft and the seat ring does not rotate. may be adopted.

(Effect of the invention) Since this invention is constructed as described above, when the seal cover is fixed to the main body of the device,
A minute flow path for preventing dust intrusion is formed outside the seal cover by a fixed seal member and a rotating seal member in a non-contact state. Therefore, there is no need to position the dust sealing means after mounting it on the device body, and no axial space is required for positioning, so the entire device can be downsized.

In addition, since the rotating seal member and the stationary seal member are not in contact with each other, there is no wear on them while the rotating shaft is rotating, which can extend the product life, and at the same time, abrasion powder can enter the shaft seal side. There is no risk that the sealing performance will deteriorate.

Furthermore, since the fixed seal member and the rotary seal member constituting the dust seal means can be separated, various excellent effects such as easy and quick replacement can be achieved.

[Brief explanation of the drawing]

FIG. 1 is a front sectional view showing an example in which this invention is applied to a mechanical seal, FIG. 2 is an exploded perspective view of the dust seal means of this invention, and FIG. 3 is a front sectional view showing a conventional example. Explanation of symbols, 1... Mechanical seal (sealing device), 3... Seal cover, 4... Shaft hole, 5...
Exterior of seal cover, 6...Rotating shaft, 19...Dust sealing means, 20... Fixed sealing member, 21
... Rotating seal member, E ... Shaft sealing part, F ... Channel.

Claims (1)

[Utility Model Claims] A shaft seal is formed to maintain a fluid-tight seal between the seal cover fixed to the device body and the rotating shaft inserted into the shaft hole of the seal cover, and in order to prevent dust from outside the seal cover from entering the shaft seal,
In a sealing device in which a dust seal means is provided on the end face side of a seal cover, the dust seal means is provided on a split-type stationary seal member attached to the seal cover side, and a minute flow path is formed between the opposing surfaces of the stationary seal member,
A sealing device comprising a split-type rotating seal member attached to the rotating shaft side so as not to come into contact with the fixed seal member.