JPH0626577A - Shaft seal device - Google Patents

Abstract

PURPOSE:To maintain good sealing capacity for a long team without entailing those of one-sided wear and local wear even if deflection occurs to a turning shaft. CONSTITUTION:In a shaft sealing device provided with a stuffing box 51, gland packing 52 and packing gland 54, an angle adjuster plate 67 is shaped like a wedge so as to conform a center line of this shaft seal device 50 with a center line of a turning shaft 21 and is installed between a tank body 11 and the stuffing box 51.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shaft sealing device for sealing fluid leakage at a rotary shaft penetrating portion of a tank body, and more particularly,
The present invention relates to a shaft sealing device which is useful when a bearing has a long distance and a rotating shaft is bent due to its weight.

[0002]

2. Description of the Related Art FIG. 3 shows a conventional shaft seal device. Rotating shaft 2
The stuffing box 51 is attached to the tank end plate 11 through which 1 passes.
Is fixed, and the gland packing 52 and the packing spacing piece 53 are filled between the shaft sleeve 22 of the rotary shaft 21 and the stuffing box 51, and the packing retainer 54 is tightened with the pressing bolt 55 to put the gland packing 52 in the space. Push in and seal off fluid leaks.

[0003]

The conventional shaft sealing device is as described above. However, when the bearing spacing for supporting the rotary shaft 21 is long and the weight applied to the rotary shaft 21 is large, the rotary shaft 21 bends. Causes stuffing box 5
1. The packing retainer 54 and the shaft sleeve 22 suffer from uneven wear and local wear due to partial contact, which reduces the sealing ability and shortens the life of the shaft sealing device.

The present invention has been made in order to solve the above problems, and even when the rotating shaft is bent, uneven wear and local wear do not occur and a good sealing ability is maintained for a long period of time. The purpose is to obtain the device.

[0005]

A shaft sealing device according to the present invention includes a stuffing box fixed to a tank body, a gland packing filled between the stuffing box and a rotary shaft, and a gland packing pushed in. In a shaft sealing device including a packing retainer, an angle adjusting plate formed in a wedge shape so that the center line of the shaft sealing device coincides with the center line of the rotating shaft is sandwiched between the tank body and the stuffing box. I wore it. An angle adjusting plate formed in a wedge shape so that the center line of the shaft sealing device coincides with the center line of the rotating shaft is sandwiched between the tank body and the stuffing box, and the end face of the packing retainer is attached. An annular body having a concave portion formed in the inner diameter is fixedly attached to the annular body, and an elastic seal ring that elastically comes into close contact with the annular body and the rotating shaft is inserted into the concave portion of the annular body.

[0006]

Since the angle adjusting plate according to the present invention has a wedge shape, the relative angle of the stuffing box with respect to the tank body is adjusted so that the center line of the shaft sealing device is centered on the rotating shaft even if the rotating shaft is bent. Match the line. As a result, uneven contact is eliminated, and uneven wear and local wear are prevented. In addition, a ring body having a recess formed in the inner diameter is fixed to the end face of the packing holder of the shaft sealing device, and an elastic seal ring that elastically comes into close contact with the ring body and the rotating shaft is inserted into the recess of the ring body. Then, even if there is a change in the rotating shaft, the elastic seal ring elastically deforms following the change and closes the ring body and the rotating shaft to seal the fluid leakage. As a result, the sealing ability of this shaft sealing device is further improved.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows a shaft sealing device according to an embodiment of the present invention. The shaft sealing device shown in FIG. 1 is a shaft sealing device provided in the kneader (acetylating machine) shown in FIG. The kneader shown in FIG. 4 is an apparatus for producing a tobacco filter raw material by stirring and mixing pulp and organic acid. Figure 4
Reference numeral 10 denotes a tank body of the stirrer, which is provided with a rotary shaft 21 penetrating both tank body end plates 11 of the tank body 10, and a stirring blade 96 is attached to the rotary shaft 21 in the tank body 10. ing. Reference numeral 91 denotes a motor, and the motor 91 includes a V-belt pulley 92, a speed reducer 93, and a shaft coupling 94 to rotate the rotary shaft 2
1 is rotationally driven. The rotary shaft 21 is supported by a free side bearing 31 and a drive side bearing 32, and a shaft sealing device 50 is provided at a position where the rotary shaft 21 penetrates both tank body end plates 11, respectively. Sealing the leak. The structure of this shaft sealing device 50 is shown in FIG.

In FIG. 1, 11 is a tank end plate, and 21 is a rotating shaft. The rotating shaft 21 penetrates through a hole formed in the tank end plate 11, and a shaft sealing device 50 that seals fluid leakage is provided in this penetrating portion where the rotating rotating shaft 21 penetrates. A shaft sleeve 22 is externally fitted and fixed to a portion of the rotary shaft 21 which penetrates the tank body end plate 11 and the shaft sealing device 50 by means such as shrink fitting. The shaft sleeve 22 is made of a corrosion-resistant material and is formed into a perfect circular cylindrical shape and has a smooth outer surface in order to maintain a good shaft sealing function.

In FIG. 1, main components of the shaft sealing device 50 are a stuffing box 51 fixed to the tank end plate 11 with a plurality of mounting bolts 58, and a space between the stuffing box 51 and the shaft sleeve 22. It is composed of a gland packing 52 and a packing gap piece 53 to be filled in, a packing presser 54 for pushing the gland packing 52 and the packing gap piece 53, and a plurality of push-in bolts 55 for tightening the packing presser 54. The stuffing box 51 has a cylindrical shape, and on the side where the stuffing box 51 is fixed to the tank body end plate 11, the tank body end plate 1 is attached.
1 and an inward flange 51b for receiving the gland packing 52 and the packing spacing piece 53, and an outward flange 51c for mounting the push-in bolt 55 at the outer end portion.
Are formed. The cylindrical inner diameter of the stuffing box 51 is an inner diameter with which the gland packing 52 and the packing gap piece 53 should be inserted between the stuffing box 51 and the outer diameter of the shaft sleeve 22, and is formed smoothly. Gland packing 52
Is made of a flexible material such as fiber or rubber. The packing retainer 54 has a cylindrical shape, and a flange 54c is provided on the outer end.
Are formed. The packing pressing member 54 has a cylindrical inner diameter that is fitted onto the shaft sleeve 22 and an outer diameter that is fitted into the stuffing box 51. Push bolt 5
Reference numeral 5 is for screwing the packing retainer 54 by screwing it into the screw hole of the outer end flange 51c of the stuffing box 51 through the hole of the flange 54c of the packing retainer 54, and in FIG. It is composed of a push-in nut 551 and a lock nut 552. Reference numeral 56 is an O-ring that seals between the stuffing box 51 and the packing retainer 54.

In FIG. 1, an angle adjusting plate 67 is inserted and sandwiched between the mounting flange 51a of the stuffing box 51 of this shaft sealing device and the tank body end plate 11.
The angle adjusting plate 67 is a disc with a hole having a diameter larger than the cylindrical outer diameter of the portion of the stuffing box 51 in contact with the tank body end plate 11, and the front and back surfaces of the disc are not parallel. It is flat and wedge-shaped. The wedge-shaped angle between the non-parallel planes of the front surface and the back surface of the angle adjusting plate 67 is determined as follows. That is, the rotary shaft 21 of the kneader shown in FIG. 4 is supported by the free side bearing 31 and the drive side bearing 32, but the distance between the free side bearing 31 and the drive side bearing 32 is long, and the rotary shaft 21 is sturdy and heavy. Stirring blade 96
Since a large bending moment is applied to the rotary shaft 21, the rotary shaft 21 bends as shown in an exaggerated manner in FIG. The curvature and inclination of the flexure of the rotary shaft 21 can be calculated by the basic formula of material mechanics. If the bending curvature is negligible, the conventional shaft sealing device will not cause any problem, but in some devices such as the kneader shown in FIG. 4, the bending curvature of the rotary shaft 21 is too large to be ignored. The shaft sealing device has a problem that uneven wear and local wear occur due to partial contact. Therefore, the tilt angle of the rotary shaft 21 at the position of the shaft sealing device 50 caused by the bending of the rotary shaft 21 is calculated by the basic formula of material mechanics,
As shown in an exaggerated manner in FIG. 2, an angle adjusting plate 67 formed in a wedge shape by setting an angle between both non-parallel planes of the front surface and the back surface to an angle equal to the inclination angle is provided with the tank body end plate 11 and the stack. The center line of the shaft sealing device 50 is fixed to the rotary shaft 21 by sandwiching it between the fing box 51 and the mounting flange 51a.
It is designed to match the center line of.

In addition, reference numeral 69 is an O-ring, which has a structure for sealing between the tank body end plate 11 and the angle adjusting plate 67 in the figure, but the angle adjusting plate 67 and the stuffing box 5 are further provided.
The O-ring that seals between 1 and 1 may be inserted, and the hole diameter of the angle adjusting plate 67 may be increased so that the O-ring 69 seals between the tank body end plate 11 and the stuffing box 51. Good.

The tilt angle of the rotating shaft 21 at the position of the shaft sealing device 50 due to the bending and bending of the rotating shaft 21 can be calculated as follows by the basic formula of material mechanics. i = ∫ (M / EI) dx + c Here, i is the inclination angle (radian) of the rotating shaft 21, M is the bending moment applied to the rotating shaft 21, E is the longitudinal elastic modulus of the rotating shaft 21, and I is the rotating shaft 21. Second moment of area, x
Is the coordinate of the rotary shaft 21 in the axial direction, and c is the tilt angle of the rotary shaft 21 at the integration start point. The integration range is from the nearby bearing to the shaft seal device,
[∫ (M / EI) dx] is calculated, the inclination angle c of the bearing is calculated, and it is calculated as c- [∫ (M / EI) dx], or if it is bilaterally symmetric, the shaft is sealed from the center. It may be obtained by integrating up to the device and setting c = 0.

In the embodiment shown in FIG. 1, the packing retainer 54
A first-arrival ring body 71 and a second-strand ring body 72 are fixed to the end surface of the with a plurality of mounting bolts 78. A concave portion is formed on the inner diameter surface of the rear ring body 72 on the front ring body 71 side.
And a groove-shaped recess is formed between them and. An O-ring 76 is fitted between the packing retainer 54 and the first-arrival ring 71, and an O-ring 77 is fitted between the first-limb ring 71 and the trailing-ring body 72. An elastic V-shaped seal ring 73 is provided in a groove-shaped recess formed in the inner diameters of the first-arrival ring body 71 and the second-strand ring body 72.
And the tightening band 74 is inserted. The elastic V-shaped seal ring 73 is made of synthetic rubber or the like and has a V-shaped cross section. The lower end of the V-shaped cross section elastically comes into close contact with the rotating shaft 21, and the upper ends of the V-shaped groove are groove-shaped recesses. It is formed so as to be elastically intimately contacted with the first-arriving ring body 71 and the second-ring body 72 which form both side surfaces (end surfaces) of the. The tightening band 74 is formed so that the elastic V-shaped seal ring 73 is tightened with an appropriate force to ensure a close contact.

Next, the operation of this shaft seal device will be described. As shown in FIG. 1, the stuffing box 51 is attached to the tank body end plate 11 with the angle adjusting plate 67 interposed therebetween, and the gland packing 52 is provided in the cylindrical space between the stuffing box 51 and the shaft sleeve 22 of the rotary shaft 21. And the packing gap piece 53, and then the packing presser 54, and insert the presser bolt 55 into the screw hole of the flange 51c of the stuffing box 51 by inserting the presser bolt 55 into the screw hole of the flange 51c of the stuffing box 51. The nut 551 is screwed in, the packing retainer 54 is pushed into the stuffing box 51, the gland packing 52 is pressed, and the gland packing 52 is attached to the shaft sleeve 2.
The outer surface of 2 and the inner surface of the stuffing box 51 are brought into close contact with each other. However, it is assumed that the pushing force is too strong and there is no problem such as generation of large frictional heat as the rotary shaft 21 rotates. After tightening the push-in nut 551, the lock nut 552 is screwed in to prevent loosening. As a result, the gland packing 52 fills the space between the stuffing box 51 and the shaft sleeve 22, and the rotary shaft 21 rotates, causing a radial direction between the outer surface of the shaft sleeve 22 and the inner surface of the stuffing box 51. Even if there is a slight variation in the distance between the two, it closely fits the surface of the shaft sleeve 22 and seals the leakage of fluid passing therethrough.

However, as described with exaggeratedly shown in FIG. 2, when the bearing spacing of the rotating shaft 21 is long and the rotating shaft 21 is bent due to its weight, the stuffing box 51 in FIG. When attached to the end plate 11 at a right angle,
The center line of the shaft sealing device 50 does not coincide with the center line of the rotating shaft 21, the shaft sealing device 50 is unevenly contacted, the stuffing box 51 and the packing retainer 54 are unevenly worn, and the shaft sleeve 22 is locally worn. Occurs and leakage easily occurs. Therefore, as means for matching the center line of the shaft sealing device 50 with the center line of the rotating shaft 21, an angle adjusting plate 67 having a front surface and a back surface which are non-parallel planes is provided between the tank body end plate 11 and the stuffing box 51. It is sandwiched between them. If the angle of the non-parallel plane of the angle adjusting plate 67 is set to the inclination angle at the position of the shaft sealing device due to the bending of the rotary shaft 21 described above, the angle adjusting plate 67 is sandwiched to form the shaft sealing device 5.
The center line of 0 can be matched with the center line of the rotating shaft 21. By mounting the shaft seal device 50 so that the center line of the shaft seal device 50 coincides with the center line of the rotary shaft 21 in this manner, uneven wear occurs in the stuffing box 51 and the packing retainer 54, or local wear occurs in the shaft sleeve 22. Is prevented. Thereby, a good shaft sealing function can be maintained for a long period of time.

As shown in FIG. 1, when the first-arrival ring 71 and the second-strand ring 72 are attached and the elastic V-shaped seal ring 73 and the tightening band 74 are fitted into the groove-shaped recesses, the elastic V-shaped seal is formed. The bottom of the V-shaped cross section of the ring 73 elastically comes into close contact with the rotating shaft 21, and the upper end portions on both sides of the V-shaped cross section of the elastic V-shaped seal ring 73 are the end faces of the first-attached ring body 71 and the rear-attached ring body 72 ( Since the rotation shaft 21 elastically comes into close contact with the groove-shaped side surface), even if the rotating shaft 21 slightly fluctuates in the radial direction due to fluctuations in the stirring reaction force, etc., the fluid leakage is sealed and the gland packing 52 has the above-mentioned sealing function. Together, they further improve the fluid leakage sealing performance of this shaft sealing device.

In FIG. 1, the shaft sleeve 22 is provided in a range facing the stuffing box 51, the gland packing 52, and the packing retainer 54.
It is desirable to extend and provide to the range facing the 1, 72 and the elastic V-shaped seal ring 73.

[0018]

As described above, according to the present invention, since the angle adjusting plates are sandwiched and the center line of the shaft sealing device is aligned with the center line of the relevant portion of the rotary shaft, uneven wear and local wear are caused. Can be prevented and good shaft sealing performance can be maintained for a long period of time. Further, if an elastic V-shaped seal ring is attached, the shaft sealing performance can be further improved.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a shaft sealing device according to an embodiment of the present invention.

FIG. 2 is an exaggeratedly expressed longitudinal sectional view of a shaft sealing device according to an embodiment of the present invention.

FIG. 3 is a vertical sectional view of a conventional shaft sealing device.

FIG. 4 is a side vertical sectional view of a stirring device to which the shaft sealing device according to the present invention is applied.

[Explanation of symbols]

10: tank body, 11: tank body end plate, 21: rotating shaft, 2
2: Shaft sleeve, 31: Free side bearing, 32: Drive side bearing, 50: Shaft sealing device, 51: Stuffing box,
52: Gland packing, 54: Packing retainer, 5
5: Push-in bolt, 67: Angle adjusting plate, 71, 72: Ring body, 73: Elastic V-shaped seal ring, 74: Tightening band.

Claims (2)

[Claims] 1. A shaft sealing device comprising a stuffing box fixed to a tank body, a gland packing filled between the stuffing box and a rotary shaft, and a gland packing for pushing the gland packing. A shaft sealing device, wherein an angle adjusting plate formed in a wedge shape so that a center line of the device coincides with a center line of the rotating shaft is sandwiched between the tank body and the stuffing box. 2. A shaft sealing device comprising a stuffing box fixed to a tank body, a gland packing filled between the stuffing box and a rotating shaft, and a gland packing for pushing the gland packing. An angle adjusting plate formed in a wedge shape so that the center line of the device coincides with the center line of the rotating shaft is sandwiched between the tank body and the stuffing box, and an inner diameter portion is formed on an end surface of the packing retainer. A shaft sealing device, wherein a ring body having a concave portion is fixed, and an elastic seal ring that elastically comes into close contact with the ring body and the rotary shaft is inserted into the concave portion of the ring body.