JPH10159983A - Sealing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve durability of a lip, reduce damage of the lip, and maintain sealing performance over a long period of time by forming one seal member of a resinous seal ring having a slidingly movable surface to contact with a mating member, and forming the other seal member of a seal lip composed of a rubber-like elastic body. SOLUTION: A cross-sectional almost U-shaped reinforcing ring 13 whose inside is put in an opening condition, is formed by joining of first and second reinforcing rings 11 and 12. An inside area of the reinforcing ring 13 functions as a holding chamber H to hold a resinous seal ring 14 as a first seal member. The seal ring 14 is a cross-sectional rectangular shape, and has a slidingly movable surface 14a having a parallel part whose inner peripheral surface is brought into contact with an outer peripheral surface of a roller shaft 2a in a sealed condition. An annular rubber ring 15 composed of a rubber-like elastic body as an energizing member to impart energizing force to generate tensile force of the slidingly movable surface 14a of the seal ring 14 to the seal ring 14, is arranged on the outer peripheral side in the holding chamber H, and energizes the seal ring 14 on the inner peripheral side in the diametrically contracting direction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sealing device used for, for example, a dust seal for a bearing of a roll for a continuous casting machine.

[0002]

2. Description of the Related Art As a conventional sealing device of this type, for example, the one shown in FIG. 3 is known. That is,
The sealing device 100 is used to prevent foreign matter (hereinafter referred to as dust) such as dust and cooling water from entering the bearing 102 of the roll shaft 101a of the roll 101 for a continuous casting machine from the roll body 101b side. The infiltration of foreign matter from the open side 107 is double-sealed by two seal members 104 and 105 arranged in the axial direction.

In order to prevent the seal lips 104a and 105a of each of the seal members 104 and 105 from being damaged by lubrication of the sliding surfaces of the lips and foreign matter,
After the lubrication of the bearing 102 is performed on the liquid lubricant 106, such as grease or oil, supplied from the back side of the first seal member 104 (left side in the figure) along the path indicated by the arrow A101. It is supplied to each seal member to lubricate the sliding surfaces of the seal lips 104a and 105a,
In addition, dust entering between contact surfaces with the roll shaft 101a was discharged in the direction of arrow A102.

[0004] A seal member 203 shown in FIG. 4 includes a continuous casting machine roll 201 similar to the continuous casting machine roll 101.
Roller 2 for continuous casting machine on bearing 202 provided at the end of
01 is used to prevent dust from entering from the end 201a side.

[0005] The sealing member 203 includes a main lip 203a made of a rubber-like elastic member and a main lip 203a.
Is provided integrally with a dust lip 203b disposed outside of the device. Then, similarly to FIG. 3, the liquid lubricant 106 such as grease or oil supplied to the bearing 202 is
After the lubrication of the bearing 202 is performed, the lubricant is supplied from the back side (the right side in the figure) of the seal member 203 along the path of the arrow A201 to lubricate the sliding surfaces of the main lip 203a and the dust lip 203b. Dust entering between contact surfaces with the portion 201a was discharged in the direction of arrow A202.

[0006]

However, any of the sealing devices according to the prior art described above requires a liquid lubricant 106.
Depending on the viscosity characteristics (depending on the viscosity characteristics, a phenomenon occurs in which the viscosity becomes high at low temperatures and the flow becomes difficult), the amount of lubrication, etc., may affect the sealed state and the dust discharging property.

[0007] Therefore, when the dust discharging property is reduced and foreign substances cannot be sufficiently washed away, residual dust is generated in the vicinity of the outer seal lip 105a and dust lip 203b, and the outer seal lip 105a and dust lip 105a 203b may be damaged, and dust may enter the space 108 between the seal members 104 and 105 and the lip 203c.

The dust penetrating into the space 108 and between the lips 203c bites into the sliding surface of the lip, causing early wear of the sealing lip and the sliding surface of the shaft, thereby deteriorating the sealing performance. And the like may occur, causing a problem of bearing damage due to rust, deterioration of rotation accuracy, and the like.

Further, in order to improve the lubrication of the seal member and the dust discharging property, a liquid lubricant 1 supplied to the bearing is provided.
It is conceivable to increase the supply pressure or the supply amount of the seal lip in this case, but in this case, since the seal lip is a rubber-like elastic member and has low rigidity, it is difficult to adjust the lip valve opening amount by pressurization, and the Consideration must be given to the problem of increased consumption of the agent 106 and the danger of dust ingress when the lip is opened.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the prior art.
By improving the durability of the lip and improving the lubricant holding capacity and reducing the consumption of lubricant, it is possible to reduce the breakage of the lip of the sealing device and maintain the sealing performance for a long time. To provide a sealing device.

[0011]

In order to achieve the above object, the present invention seals between two members which are concentrically and relatively rotatably assembled with each other. An annular fixing portion fixed to the member of
A sealing device including a first seal member and a second seal member on the dust side, which are slidably and sealingly contacted with the other member and are disposed on the seal side to which the lubricant is supplied;
The first seal member is a resin seal ring having a sliding surface that comes into contact with a mating member, and the second seal member is a seal lip made of a rubber-like elastic body. .

[0012] According to this, dust intrusion is prevented by the second seal member, and even if dust invades from the second seal member to the first seal member, the first seal member slides on the sliding surface. The seal is made of a resin and at the same time has a high lip rigidity, so that dust does not easily enter the sliding surface and is not easily scratched by dust, so that the sealing performance of the first seal member is maintained. And durability can be improved. Then, with respect to the change in the supply pressure of the lubricant supplied from the sealing side, the change in the opening amount of the sliding surface due to the rigidity of the first seal member is small, and the amount of the lubricant is stable. Excessive consumption of lubricant can be suppressed.

The annular fixing portion includes an axial portion fitted to one member, and two radial portions extending from both ends of the axial portion so as to approach the other member. A region surrounded by the axial portion and the two radial portions is a holding chamber for the resin-made seal ring, and the holding chamber is configured to generate a tightening force on the other member of the resin-made seal ring. It is also preferable to provide an annular urging member made of a rubber-like elastic body that applies an urging force.

According to this, the axial position of the resin seal ring is determined by the two radial portions forming the holding chamber, and the annular biasing member made of a rubber-like elastic member slides on the other member. A surface tension is generated to form a uniform and stable sealing contact in the annular direction. The annular biasing member can prevent the lubricant supplied from the sealed side in the holding chamber from passing through the dust side from other than the sliding surface.

It is also preferable that a sliding groove is provided on the sliding surface of the resin seal ring so as to discharge a small amount of lubricant supplied from the sealing side to the dust side.

This sliding groove makes it possible to reliably supply lubricant to the sliding surface of the seal ring, and to constantly supply new lubricant to the sliding surface at a predetermined ratio, and to supply the lubricant to the sliding surface. Since the retained lubricant is discharged, the sliding surface can be kept clean, and the durability of the seal ring can be improved.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION

(Embodiment 1) Hereinafter, a first embodiment of the present invention will be described with reference to FIG. FIG. 1A shows an example of a sealing device 1 according to a first embodiment of the present invention, and FIG. In FIG. 1 (b), a sealing device 1 to which the present invention is applied is in sliding contact with a roll shaft 2a of a roll 2 of a continuous casting machine or the like, similarly to the sealing device described in the section of the prior art. A case in which dust is prevented from entering the bearing 3 from the dust-side space D will be described as an example (the opposite side of the dust-side space D is referred to as a sealed-side space M).

The sealing device 1 comprises a fixed seal housing 4 as one of two members which are assembled concentrically and relatively rotatably with each other, and a rotating roll shaft 2a as the other member. And is fitted and fixed to the inner peripheral surface of a cylindrical mounting cap 4b fixed to the opening end surface 4a of the seal housing 4 with bolts 4c or the like.

The sealing device 1 includes a first reinforcing ring 11 having a substantially L-shaped cross section and having an axial portion 11a and a radial direction 11b protruding inward from one end of the axial portion 11a. The reinforcing ring 11 is integrally provided with a fitting portion 11c of a rubber-like elastic body and a dust lip 11d as a second sealing member.

The axial portion 11 of the first reinforcing ring 11
A second reinforcing ring 12 is fitted inside a. The second reinforcing ring 12 has a substantially L-shaped cross section including an axial portion 12a and a radial direction 12b protruding inward from one end of the axial portion 12a, so that the radial direction 11b is separated from the radial direction 12b. After the axial portion 12a is fitted inside the axial portion 11a of the reinforcing ring 11, the end portion 11e of the axial portion 11a of the reinforcing ring 11 is bent inward to be fixed by caulking.

Accordingly, the first and second reinforcing rings 11, 12
Will form a reinforcement ring 13 having a substantially U-shaped cross section with the inside open. And this reinforcement ring 1
The inner region of 3 functions as a holding chamber H that holds a resin seal ring 14 as a first seal member.

The seal ring 14 has a rectangular cross section.
A sliding surface 14a having a parallel portion for sealingly contacting the inner peripheral surface with the outer peripheral surface of the roll shaft 2a is provided.

As the material of the seal ring 14, a resin material having a small sliding resistance and excellent abrasion resistance to dust is selected. For example, a fluorine-based resin such as PTFE (tetrafluoroethylene resin) can be used.
The resin material such as PTFE may be filled with various fillers such as glass fiber, graphite, and carbon fiber depending on the use. Of course, not only these resin materials but also various other materials can be selected.

The sliding surface 14a of the seal ring 14
The urging force for generating the tension of the seal ring 1
An annular rubber ring 15 made of a rubber-like elastic body as an urging member to be provided to 4 is disposed on the outer peripheral side in the holding chamber H,
The seal ring 14 on the inner peripheral side is urged in a direction to reduce the diameter. The rubber ring 15 and the seal ring 14 may have a configuration in which separate members are fitted, or a configuration in which they are integrally joined by bonding or the like.

The rubber ring 15 and the seal ring 14 are assembled into the holding chamber H by inserting the rubber ring 15 and the seal ring 14 inside the second reinforcing ring 12 before fitting the first reinforcing ring 11 and the second reinforcing ring 12 together. It is possible to adopt a method of arranging and assembling, or a method of fitting the first reinforcing ring 11 and the second reinforcing ring 12 and then bending each of them to deform the shape, and assembling into the holding chamber H. is there.

A portion of the seal housing 4 holding the bearing 3 is provided with an oil supply hole 4d, and a lubricant L such as grease is supplied to the bearing 3 at a predetermined pressure. After lubricating the bearing 3, the lubricant L is supplied to the sealing device 1 along the path indicated by the arrow A1.

Next, the operation of the sealing device 1 will be described.
The dust lip 11d prevents dust from entering from the dust side space D. Even if dust enters from the dust lip 11d to the seal ring 14, the lubricant L is retained on the sliding surface 14a of the seal ring 14. At the same time
Since it is made of a resin such as PTFE, the lip rigidity is high and dust hardly penetrates into the sliding surface 14a, and it is hard to be damaged by the dust. Therefore, the sealing performance of the seal ring 14 can be maintained and the durability can be enhanced.

A change in the supply pressure of the lubricant L supplied from the sealing side space M due to a change in the pressure in the sealing side space M or the like causes the sliding surface 14 due to the rigidity of the seal ring 14 to change.
Since the change in the opening amount of “a” is small and the communication amount of the lubricant L is stable, excessive consumption of the lubricant L can be suppressed.

The axial position of the seal ring 14 is determined by the holding chamber H, and the rubber ring 15 uniformly generates a tightening force of the sliding surface 14a against the roll shaft 2a in the annular direction to form a stable sealed contact state. I do. And
The rubber ring 15 can prevent the lubricant L supplied from the sealed space M in the holding chamber H from flowing into the dust-side space D from other than the sliding surface 14a.

Here, the reinforcing ring 13 includes two reinforcing rings 1.
Although the holding chamber H is formed by combining the elements 1 and 12, the holding chamber H may have an integral configuration having a U-shaped cross section.

(Embodiment 2) FIG. 2 is a view for explaining a second embodiment of the present invention. This sealing device 21
The basic configuration is the same as that of the first embodiment, and the same components are denoted by the same reference numerals. The characteristic part of the sealing device 21 is the sliding surface 1 of the seal ring 14.
4a is provided with a sliding groove 22 that enables a small amount of the lubricant L supplied from the sealed space M to be discharged to the dust space D.

In this embodiment, the sliding groove 22 is
Although it is an iris pattern, it is not limited to this form, and may be a pattern extending obliquely in an annular direction or a spiral pattern.

The operation of the sealing device 21 is such that the sliding groove 22 reliably lubricates the sliding surface 14a, and a new lubricant L is always supplied to the sliding surface 14a at a predetermined ratio. Since the lubricant L held on the moving surface 14a is discharged, the sliding surface 14a can be constantly maintained in a clean state, and the wear of the seal ring 14 and the roll shaft 2a can be reduced. It is possible to maintain stable sealing performance of the sealing device 21 for a long time.

[0034]

As described above, according to the present invention,
Dust intrusion is prevented by the second seal member, and even if dust invades from the second seal member to the first seal member, the first seal member retains the lubricant on the sliding surface and simultaneously Since it is made of a resin seal ring, the lip rigidity is high and dust hardly penetrates into the sliding surface, and the dust is hardly scratched.
It is possible to maintain the sealing performance of the sealing member and enhance the durability.

With respect to the change in the supply pressure of the lubricant supplied from the sealing side, the change in the opening amount of the sliding surface due to the rigidity of the first seal member is small, and the amount of the lubricant passing through is stable. As a result, excessive consumption of the lubricant can be suppressed, so that breakage of the lip of the sealing device can be reduced and the sealing performance can be maintained for a long period of time.

By providing an annular biasing member in the holding chamber, the axial position of the resin seal ring is determined by the two radial portions forming the holding chamber, and the annular attaching member made of rubber-like elastic material is provided. The biasing member generates a tightening force of the sliding surface against the other member to form a uniform and stable sealing contact state in the annular direction. And the annular urging member is
The lubricant supplied from the sealed side in the holding chamber can be prevented from penetrating to the dust side from other than the sliding surface.

By providing a sliding groove on the sliding surface of the resin-made seal ring, it is possible to reliably supply the lubricant to the sliding surface of the seal ring, and to always supply a new lubricant at a predetermined ratio. Since the lubricant is supplied to the sliding surface and the lubricant held on the sliding surface is discharged, the sliding surface can be kept clean and the durability of the seal ring can be improved.

[Brief description of the drawings]

FIG. 1 is a sectional configuration explanatory view of a sealing device according to a first embodiment of the present invention.

FIG. 2 is an explanatory view of a sectional configuration of a sealing device according to a second embodiment of the present invention.

FIG. 3 is an explanatory view of a cross-sectional configuration of a conventional sealing device.

FIG. 4 is an explanatory view of a cross-sectional configuration of a conventional sealing device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Sealing device 2 Roll 2a Roll shaft 3 Bearing 4 Seal housing 4a Open end face 4b Mounting cap 4c Bolt 4d Oil supply hole 11 First reinforcing ring 11a Axial part 11b Radial part 11c Fitting part 11d Dustrip 11e End part 12th 2 Reinforcement ring 12a Axial portion 12b Radial portion 13 Reinforcement ring 14 Seal ring (first seal member) 14a Sliding surface 15 Rubber ring (biasing member) D Dust side space H Holding chamber M Seal side space L Lubrication Agent

Claims (3)

[Claims] 1. A seal for sealing between two members that are assembled concentrically with each other so as to be relatively rotatable, wherein an annular fixing portion fixed to one member of the two members that rotate relative to each other and a sliding member with respect to the other member. A sealing device movably in sealing contact with a first sealing member and a second sealing member on the dust side which are disposed on a sealing side to which a lubricant is supplied, wherein the first sealing member comprises: A sealing ring made of resin having a sliding surface that comes into contact with a mating member, wherein the second sealing member is a sealing lip made of a rubber-like elastic body. The annular fixing portion includes an axial portion fitted to one member, and two radial portions extending from both ends of the axial portion so as to approach the other member. A region surrounded by the axial portion and the two radial portions is defined as a holding chamber for the resin seal ring, and the holding chamber is configured to generate a tightening force on the other member of the resin seal ring. The sealing device according to claim 1, further comprising an annular urging member made of a rubber-like elastic body that applies an urging force. 3. A sliding surface of the resin seal ring,
The sealing device according to claim 1, further comprising a sliding groove that enables a small amount of lubricant supplied from the sealing side to be discharged to the dust side.