JPS6321784Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to a sealing device for a rolling bearing.

The functions of the sealing device for rolling bearings are to prevent the infiltration of fluids (water, steam, other fluids, etc.) and solids (foreign objects, dirt, etc.) from the outside into the bearing, and to prevent the intrusion of solids (foreign objects, dirt, etc.) from the inside of the bearing to the outside. The purpose is to prevent the encapsulated lubricant from leaking out.

Conventionally, various types of sealing devices described below have been put into practical use for the purpose of satisfying this function, but each of them has its own drawbacks.

The disadvantages are: (1) Rubber or other sliding material contacts the sliding surface (contact type seal) ◎ Poor sealing performance due to small sliding area.

◎ Since the sliding material is soft, it is difficult to secure a sealed surface and it is difficult to withstand high pressure differences.

◎ If the sliding material wears out, the sealing performance will deteriorate.

(2) Seals that seal up to the labyrinth gap (non-contact type seal) ◎ Due to the gap, sealing performance for solids and liquids is poor.

◎ The effect of preventing lubricant from flowing out from inside the bearing is extremely small.

(3) Items that use magnetic fluid (magnetic fluid seal) ◎ Difficult to seal high pressure spills.

◎ Effective sealing cannot be achieved depending on the compatibility of the magnetic fluid with the external fluid or solid.

etc., and there is still no product with sufficient sealing performance.

The purpose of this invention is to provide a sealing device for a rolling bearing that solves the above-mentioned drawbacks.

This device is a sealing device for a rolling bearing having a pair of bearing rings, in which a sliding surface is formed on one bearing ring, a driven ring is provided opposite the sliding surface, and the driven ring is connected directly or indirectly. a sealing portion which is fixed to an elastic member fixed to the other bearing ring and which causes the driven ring to elastically slide into contact with the sliding surface for sealing; and a support plate fixing the elastic member. An auxiliary sealing part whose inner periphery or outer periphery is close to or in sliding contact with the one raceway ring and which is located outside of the sealing part and assists the sealing part, or an inner periphery or outer periphery of the elastic member itself The sealing device for a rolling bearing includes an auxiliary sealing part that is in close or sliding contact with one of the bearing rings, is located outside the sealing part, and assists the sealing part.

Next, this invention will be described in detail with reference to an embodiment shown in the drawings.

The one in FIG. 1 is the first embodiment of this invention.
Outer ring 1 (raceway ring), inner ring 2 (raceway ring), rolling elements 3,
The bearing element consisting of the retainer 4 is the same as a normal ball bearing except for the parts related to the sealing device. A stepped portion 21 is provided at the outer peripheral end of the inner ring 2, and a sliding surface 101, which is a surface parallel to the side surface of the bearing, is formed.A stepped portion 11 is provided at the inner peripheral end of the outer ring 1, Part 1
The outer periphery of the support plate 71 is fixed in the inside of the support plate 1 by a snap spring 8. On the inner side of the support plate 71, which constitutes a sealing of the first part of the bearing by means of this fixing means, there is provided one end of a bellows-shaped spring 6, which is an elastic member extending inwardly. is stuck. A driven ring 5 is fixed to the other end of the spring 6. The driven ring 5 consists of an auxiliary member 52 having an L-shaped cross section and a sliding member 51. The inner side surface of the sliding member 51 faces the sliding surface 101, and the spring 6
The surface 1 that is ejected by the slider and comes into sliding contact with the sliding surface 101
02. Therefore, sliding surface 101 and surface 1
02, the second portion of the bearing is sealed, and furthermore, the inner periphery of the support plate 71 is extended until close to the stepped portion 21, and in the adjacent portion, the second portion of the bearing is sealed. A third part sealing aids in the part sealing. In the drawings, only the sealing device on the right side of the bearing is designated by reference numerals, but the same sealing device is also installed on the left side in this embodiment.

Next, FIG. 2 shows a second embodiment of this invention.

The bearing element consisting of the outer ring 1, the inner ring 2, the rolling elements 3, and the retainer 4 is the same as a normal cylindrical roller bearing except for the parts related to the sealing device. A stepped portion 11 is provided on the inner circumferential end surface of the outer ring 1, and a sliding surface 101 that is a surface parallel to the bearing side surface is formed. A stepped portion 21 is formed at the outer peripheral end of the inner ring 2, and an annular elastic member 6 made of rubber or the like is disposed within the stepped portion 21, the inner peripheral portion of which is fixed by its own elastic force. . Note that the reference numeral 72 is a reinforcing member of the elastic member 6. Therefore, the fixing of the inner peripheral portion of the elastic member 6 constitutes the sealing of the first portion of the bearing. A sliding ring 5 is fixed to the outer periphery of the elastic member 6. The driven ring 5 is composed of an auxiliary member 52 having an L-shaped cross section and a sliding member 51, and the inner side surface of the sliding member 51 faces the sliding surface 101 and is resiliently pushed by the elastic member 6. A surface 102 comes into sliding contact with a sliding surface 101 . Therefore, the sliding contact between the sliding surface 101 and the surface 102 constitutes a sealing of the second portion of the bearing. Further, a lip 9 is formed extending radially outward from the outer circumferential portion of the elastic member 6, and the tip of the lip 9 is connected to the stepped portion 11.
(in a conventional contact type seal structure) to form a sealing portion to assist in sealing the second portion.

Next, FIG. 3 shows a third embodiment of this invention.

The bearing element consisting of an outer ring 1, an inner ring 2, rolling elements 3, and cage 4 is the same as a normal tapered roller bearing except for the parts related to the sealing device. In this embodiment as well, sealing devices are installed on both sides of the bearing. but,
The difference between the right side and the left side in the figure is that the sliding surfaces formed on the outer ring and inner ring or the attached members are the outer ring and inner ring reversed, so the sealing device on the right side only is marked with the symbol. A stepped portion 21 is provided at the right end of the outer circumference of the inner ring 2, and the side surface of the stepped portion 21 is a surface that slopes outward in the radial direction and then inward. In this embodiment, a stepped portion 11 is provided at the right end of the inner circumference of the outer ring 1, and the sliding surface 101 is constituted by the inclined surface and a portion of the outer circumferential surface on the inclined surface side of the stepped portion 21. , the outer periphery of the support plate 71 is fixed within the stepped portion 11 by a snap spring 8. Furthermore, the gap between the wall of the stepped portion and the outer periphery of the snap spring 8 is filled with a packing 10. Therefore, the fixing and the packing 10 constitute a seal for the first portion of the bearing. One end of a bellows-shaped spring 6, which is an elastic member extending inward, is fixed to the inner end surface of the support plate 71. A driven ring 5 is fixed to the other end of the spring 6. The driven ring 5 has an inner side surface and an inner peripheral surface 102 facing the sliding surface 101, and the surface 102 is plated or the like suitable for preventing sliding contact and leakage.
The driven ring 5 is biased by a spring 6 so that the driven ring 5 slides against the sliding surface and forms a seal for the second part of the bearing. In addition, in this embodiment, the support plate 7
A lip 9 made of rubber or the like is fixed to the inner periphery of the step 21, and the tip of the lip 9 slides on the outer periphery of the stepped portion 21 to form a sealing portion to assist in sealing the second portion.

Next, FIG. 4 shows a fourth embodiment of this invention. The bearing element consisting of an outer ring 1, an inner ring 2, rolling elements 3, and cage 4 is the same as a normal ball bearing except for the parts related to the sealing device. A sliding surface 101 is formed at one outer circumferential end of the inner ring 2 and has an inclined sliding surface 101 that becomes smaller in diameter toward the side surface of the bearing. Furthermore, the outer peripheral end of the inner ring 2 is a cylindrical surface that continues to the sliding surface 101. A step 11 is provided at one inner peripheral end of the outer ring 1, and a support plate 7 having a U-shaped cross section is provided within the step 11.
An elastic member 20 that also serves as a gasket is attached to the outer periphery of 1. This mounting therefore constitutes a sealing of the first part of the bearing. One end of a bellows-shaped spring 6, which is an elastic member, is fixed to the opposite surface of the support plate 71 to the surface to which the elastic member 20 is fixed. The spring 6 extends toward the inner ring 2 and has a driven ring 5 fixed to its other end.
The driven ring 5 has a surface 102 facing the sliding surface 101.
The sliding surface 101 is elasticized by the spring 6 and
It is in sliding contact with the This sliding contact thus constitutes a sealing of the second part of the bearing. Furthermore, there is a slight gap between the inner circumferential surface of the support plate 71 and the cylindrical surface of the end of the inner ring, forming a non-contact sealing portion that assists in sealing the second portion.

In the above embodiments, the sliding surface 101 and the sliding surface 102 of the driven ring 5 are a combination of materials suitable for sliding contact and leak prevention, and each surface is coated with adhesive, thermal spraying, plating, or plating to the base material. It may be formed by a method such as Examples of materials include carbon, steel, cemented carbide, and ceramic. Furthermore, each surface is suitably well-finished and has small surface roughness and waviness, and the shape and dimensions are appropriately selected to be effective in suppressing leakage.

As explained above, the sealing device of this invention is
In particular, the sealing structure of the second portion of the bearing is made of an elastic member, so that the pressure on the sliding surface can be set to an appropriate value, and the width of the sliding surface can be appropriately increased;
Furthermore, since the present invention includes an auxiliary sealing portion that assists in sealing the second portion, the rolling bearing sealing device has significantly superior sealing performance compared to conventional devices.

[Brief description of the drawings]

1, 2, 3, and 4 are longitudinal sectional views of each embodiment of this invention, in which reference numeral 5 denotes a driven ring, and 6
1 is an elastic member, 101 is a sliding surface, and 102 is a surface that comes into sliding contact with the sliding surface.

Claims (1)

[Scope of utility model registration request] In a sealing device for a rolling bearing having a pair of bearing rings, a sliding surface formed on one bearing ring, a driven ring having a surface in sliding contact with the sliding surface, and a sliding surface formed on the other bearing ring, directly or indirectly. a sealing portion that is fixed and includes an elastic member that is fixed to the side opposite to the fixed portion of the driven ring, the surface of the driven ring elastically slidingly contacts the sliding surface; and the elastic member A sealing device for a rolling bearing, comprising: an auxiliary sealing portion in which an inner circumference or an outer circumferential edge of a support plate for fixing itself or the elastic member is close to or in sliding contact with the one raceway ring.