JP2014001803A - Sealing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sealing device in which infiltration of water in a fitting part of a sleeve member can be prevented, life of a bearing can be prolonged, the problem of dropping or moving the sleeve member does not occur, adverse influences upon a seal lip caused by deformation in fitting the sleeve member are suppressed and thermal influences upon the seal lip are reduced.SOLUTION: The sealing device comprises: a housing; a shaft member; a sleeve member which is fitted and fixed to an outer peripheral surface of the shaft member; and a seal member which is fitted and fixed to an inner peripheral surface of the housing and slides with the sleeve member for sealing. In the sealing device, the sleeve member includes a second cylindrical part which is concentrically returned from one end in an axial direction inside of a first cylindrical part while keeping a fixed interval with an inner peripheral surface of the first cylindrical part. The second cylindrical part is fitted and fixed to the outer peripheral surface of the shaft member and in a distal end portion outside of the second cylindrical part, a gasket member made of an elastic material is provided while being sealed in contact with the shaft member.

Description

  The present invention relates to a sealing device, and more particularly to a sealing device used in a rotational speed sensor built-in bearing device that detects the rotational speed of a wheel of an automobile or the like.

Conventionally, a sealing device shown in FIG. 4 is known.
That is, in the wheel bearing in which the seal member 400 is provided between the shaft member 200 that rotates via the rolling element and the housing 100, an encoder 350 integrated with the sealing device has been proposed.

The seal member 400 is present on the inner side Y (left side in the drawing) of the sleeve member 300 having an L-shaped cross section, and radially outward from the cylindrical portion 310 of the sleeve member 300 and one axial end of the cylindrical portion 310. A sealing lip 410 is provided in elastic contact with the extending flange portion 340.
The cylindrical portion 310 of the sleeve member 300 is fitted and fixed to the outer peripheral surface of the shaft member 200.
In addition, an encoder 350 made of an elastic member mixed with magnetic powder is integrally provided on the outer side X (right side in the drawing) of the flange portion 340.

However, although the cylindrical portion 310 of the sleeve member 300 is fitted and fixed to the outer peripheral surface of the shaft member 200, a small amount of water may enter the bearing inside Y side from the fitting portion.
When such water intrusion occurs, rust is generated in the sleeve member 300 or the like, which is a metal material present on the inner Y side, causing a problem that premature wear of the seal lip 410 occurs.
In addition, the internal grease deteriorated and the bearing life was reduced.

  Further, in order to increase the fitting force of the sleeve member 300, it is necessary to push the sleeve member 300 into the outer peripheral surface of the shaft member 200 with a strong force, so that the sleeve member 300 is deformed and is in good contact with the seal lip 410. There was a danger that could not be obtained.

  Furthermore, the cylindrical portion 310 of the sleeve member 300 on which the seal lip 410 seals and slides is directly fitted and fixed to the outer peripheral surface of the shaft member 200, so that the sliding heat of the seal lip 410 is dissipated to the outside X. Not only is this difficult, but the heat on the shaft member 2 side is directly transmitted to the cylindrical portion 310, which causes a problem that the seal lip 410 is quickly deteriorated by heat.

A sealing device shown in FIG. 5 has been proposed as a countermeasure plan for the above-described prior art. (Patent Document 1)
A significant difference from the sealing device shown in FIG. 4 is that a gasket member 330 that integrally extends from an encoder 350 made of an elastic member mixed with magnetic powder provided on the outer side X of the flange portion 340 is integrally provided. The gasket member 330 is in elastic contact with the outer peripheral surface of the shaft member 200.

  Certainly, the provision of the gasket member 330 eliminates the possibility of a small amount of water entering the Y side of the bearing from the fitting portion of the cylindrical portion 310. However, the sleeve member 300 is deformed, and the seal lip 410 is excellent. The danger that the contact state cannot be obtained and the sliding heat of the seal lip 410 are not easily dissipated to the outside X, but the heat on the shaft member 2 side is directly transmitted to the cylindrical portion 310, so the seal lip 410 is heated quickly. The problem of deteriorating could not be solved.

Furthermore, a sealing device shown in FIG. 6 has been proposed as a countermeasure for the prior art.
A significant difference from the sealing device shown in FIG. 4 is that an elastic material coating layer 360 is provided on the inner peripheral surface of the cylindrical portion 310 of the sleeve member 300, and the cylindrical portion 310 and the outer peripheral surface of the shaft member are fitted to each other. A proposal has been made to eliminate the problem that a small amount of water enters the Y side of the bearing from the portion.

  However, when the coating layer 360 made of an elastic material is formed, the fitting force is insufficient, and there is a possibility that the sleeve member 300 is detached or moved to the inner side Y (inside the bearing) of the sleeve member 300.

JP 2007-187319 A

  Therefore, in view of the above-described situation, the present invention can prevent water from entering the fitting portion of the sleeve member, improve the bearing life, prevent the sleeve member from coming off and moving, and fit the sleeve member. An object of the present invention is to provide a sealing device that suppresses adverse effects on the seal lip due to deformation at the time of joining and reduces the thermal influence on the seal lip.

  In order to achieve the above object, according to the present invention, a housing, a shaft member that rotates while being inserted into the inner peripheral side of the housing, and an L-shaped cross section that is fitted and fixed to the outer peripheral surface of the shaft member And a sealing member having a sealing lip portion made of an elastic material that is fitted and fixed to the inner peripheral surface of the housing and slidingly slides on the sleeve member. A second cylindrical portion that is concentrically folded from an inner axial end of the first cylindrical portion with a constant gap from the inner peripheral surface of the first cylindrical portion; The second cylindrical portion is fitted and fixed to the outer peripheral surface of the shaft member, and a gasket member made of an elastic material that is in sealing contact with the shaft member is provided at the outer end portion of the second cylindrical portion. It is characterized by that.

The present invention has the following effects.
According to the sealing device of the first aspect of the present invention, the sleeve member has a certain gap from the inner circumferential surface of the first cylindrical portion from one end in the axial direction inside the first cylindrical portion. The second cylindrical portion is concentrically folded, the second cylindrical portion is fitted and fixed to the outer peripheral surface of the shaft member, and the shaft member is attached to the outer end portion of the second cylindrical portion. Since the gasket member made of an elastic material that is in sealing contact with the sleeve is provided, water can be prevented from entering the fitting portion of the sleeve member, the bearing life can be improved, and the sleeve member can be detached or moved. In addition, an adverse effect on the seal lip portion due to deformation when the sleeve member is fitted can be suppressed, and a thermal influence on the seal lip portion can be reduced.
According to the sealing device of the second aspect of the present invention, the outer front end portion of the second cylindrical portion is bent radially inward and abuts on the first annular step provided on the shaft member, Since the gasket member is configured to be in contact with the outer peripheral surface of the first annular stepped portion, the sleeve member can be accurately positioned, so that good sealing performance can be maintained.

Furthermore, according to the sealing device of the invention described in claim 3, since the elastic material encoder mixed with magnetic powder is integrally formed on the outer side of the flange portion extending radially outward of the sleeve member, It is useful as a wheel sealing device for rotation detection.
Further, according to the sealing device of the invention described in claim 4, since the encoder and the gasket member are integrally formed of an elastic material mixed with magnetic powder, molding is easy.

  Furthermore, according to the sealing device of the invention described in claim 5, since the second cylindrical portion is configured to be fitted and fixed to the outer peripheral surface of the second annular step provided on the shaft member, the sleeve As a result of accurate positioning of the members, good sealing performance can be maintained.

The longitudinal cross-sectional view of the sealing device which concerns on the 1st aspect of this invention. The longitudinal cross-sectional view of the sealing device which concerns on the 2nd aspect of this invention. The longitudinal cross-sectional view of the sealing device which concerns on the 3rd aspect of this invention. The longitudinal cross-sectional view of the sealing device which concerns on a prior art. The longitudinal cross-sectional view of the other sealing device which concerns on a prior art. The longitudinal cross-sectional view of the further another sealing device which concerns on a prior art.

Hereinafter, the best mode for carrying out the present invention will be described.
A first mode for carrying out the present invention will be described with reference to FIG.

  As shown in FIG. 1, the first aspect of the sealing device according to the present invention is a housing 1 corresponding to an outer ring, and a shaft member 2 corresponding to an inner ring that rotates while being inserted into the inner peripheral side of the housing 1. A sleeve member 3 having an L-shaped cross section that is fitted and fixed to the outer peripheral surface of the shaft member 2, and a sealing lip made of an elastic material that is fitted and fixed to the inner peripheral surface of the housing 1 and that slides hermetically with the sleeve member 3 It is comprised from the sealing member 4 provided with the part 41. FIG.

  The sleeve member 3 is concentric with an inner peripheral surface of the first cylindrical portion 31 and a constant gap D from one axial end of the inner side Y (left side in the drawing) of the first cylindrical portion 31. It has the 2nd cylindrical part 32 folded in the shape.

  That is, the axial component of the sleeve member 3 having an L-shaped cross section is fitted to the outer peripheral surface of the shaft member 2 and the first cylindrical portion 31 that is located on the radially outer side and slides in a sealed manner with the seal lip portion 41. A two-layer structure of the second cylindrical portion 32 to be fixed is formed.

  With such a configuration, it is possible to prevent water from entering the fitting portion of the sleeve member 3, improve the bearing life, prevent the sleeve member 3 from coming off and moving, and fit the sleeve member 3. The adverse effect on the seal lip portion 41 due to the deformation at the time of joining can be suppressed, and the thermal influence on the seal lip portion 41 can be reduced.

Further, the second cylindrical portion 32 is integrally provided with a gasket member 33 made of an elastic material that is in sealing contact with the shaft member 2 at the distal end portion 321 of the outer side X (right side in the drawing).
The distal end portion 321 is bent radially inward and comes into contact with the first annular step portion 21 provided on the shaft member 2, and the gasket member 33 comes into contact with the outer peripheral surface of the first annular step portion 21. ing.

  For this reason, the tip portion 321 and the first annular step portion 21 come into contact with each other to determine the axial positions of the shaft member 2 and the sleeve member 3, so that the sleeve member 3 can be accurately positioned in the axial direction. Can maintain high sealing performance.

Further, the second cylindrical portion 32 is fitted and fixed to the outer peripheral surface of the second annular step portion 22 having a larger diameter on the inner side Y than the first annular step portion 21 provided on the shaft member 2. Yes.
Since the U-shaped bent portion 311 connecting the second cylindrical portion 32 and the first cylindrical portion 31 is in contact with the second annular step portion 22, the sleeve member 3. As a result of further improved positioning in the axial direction, better sealing performance can be exhibited.

In addition, the sealing member 4 includes a flange portion 422 that extends inward in the radial direction of the reinforcing ring 42, in which a cylindrical portion 421 of a reinforcing ring 42 made of a metal material having an L-shaped cross section is fitted and fixed to the inner peripheral surface of the housing 1. The seal lip portion 41 made of a rubber-like elastic material is integrally formed.
The seal lip portion 41 is in elastic contact with the end surface seal lip portion 41 that is in elastic contact with the inner side Y of the flange portion 34 that extends outward in the radial direction of the sleeve member 3 and the outer peripheral surface of the first cylindrical portion 31. The radial seal lip portion 41 is provided.

  As a result, the end face seal lip portion 41 prevents intrusion of muddy water and earth and sand from the outer side X into the inner side Y, and the radial seal lip portion 41 prevents leakage of lubricant such as grease from the inner side Y to the outer side X. Give me.

Next, a second mode for carrying out the invention will be described with reference to FIG.
The difference from the first embodiment described above is that an elastic material encoder 35 mixed with magnetic powder is integrally formed on the outer side X of the flange portion 34 extending radially outward of the sleeve member 3. is there.

  Because of such a configuration, it is useful as a wheel sealing device for detecting rotation, which detects the rotation state of the rotating wheel (shaft member 2) relative to the stationary wheel (housing 1).

Next, a third mode for carrying out the invention will be described with reference to FIG.
The difference from the second aspect described above is that the encoder 35 and the gasket member 33 are integrally formed of an elastic material mixed with magnetic powder.

Thus, since the encoder 35 and the gasket member 33 are integrally formed of an elastic material mixed with magnetic powder, molding is easy.
Even if the second cylindrical portion 32 is deformed when fitted and fixed to the outer peripheral surface of the second annular step portion 22 of the shaft member 2, the second cylindrical portion 32 and the first cylindrical portion 32 are The elastic material layer existing between the cylindrical portion 31 absorbs this deformation and does not adversely affect the first cylindrical portion 31.

  It is suitably used as a sealing device used in a rotation speed sensor built-in bearing device that detects the rotation speed of a wheel of an automobile or the like.

DESCRIPTION OF SYMBOLS 1 Housing 2 Shaft member 3 Sleeve member 4 Seal member 21 1st cyclic | annular step part 22 2nd cyclic | annular step part 31 1st cylindrical part 32 2nd cylindrical part 33 Gasket member 41 Seal lip part 42 Reinforcement ring 311U Shaped bent portion 321 Axial tip 421 cylindrical portion 422 flange portion

Claims (5)

A housing (1), a shaft member (2) rotating in a state inserted in the inner peripheral side of the housing (1), and an L-shaped cross section fitted and fixed to the outer peripheral surface of the shaft member (2) A seal member (4) provided with a sleeve member (3) and an elastic seal lip portion (41) fitted and fixed to the inner peripheral surface of the housing (1) and slidingly sliding with the sleeve member (3) In a sealing device comprising:
The sleeve member (3) has a constant gap (D) from the inner peripheral surface of the first cylindrical portion (31) from one axial end on the inner side (Y) of the first cylindrical portion (31). And the second cylindrical portion (32) folded concentrically, and the second cylindrical portion (32) is fitted and fixed to the outer peripheral surface of the shaft member (2). An elastic material gasket member (33) in sealing contact with the shaft member (2) is provided at the outer end (X) of the second cylindrical portion (32). Sealing device.   The distal end portion (321) is bent radially inward and abuts on a first annular step (21) provided on the shaft member (2), and the gasket member (33) is in the first annular shape. The sealing device according to claim 1, wherein the sealing device is in contact with the outer peripheral surface of the stepped portion (21).   The elastic encoder (35) mixed with magnetic powder is integrally formed on the outer side (X) of the flange portion (34) extending radially outward of the sleeve member (3). 3. The sealing device according to 1 or 2.   The sealing device according to any one of claims 1 to 3, wherein the encoder (35) and the gasket member (33) are integrally formed of an elastic material mixed with magnetic powder.   The second cylindrical portion (32) is fitted and fixed to an outer peripheral surface of a second annular step portion (22) provided on the shaft member (2). The sealing device according to any one of the above.

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