JP2000193097A - Sealing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sealing device to improve sealability and enlarge the usable application range of the sealing device. SOLUTION: This sealing device seals a gap between a housing 2 and a shaft 3, which ate relatively rotatably assembled together concentrically to each other, and comprises a first seal member 5 mounted on the shaft 3 and having a flange part 4 situated on the atmosphere side A, and a second seal member 6 mounted on the housing 2 and having a metallic ring 8 and a seal lip part 10 making slide contact with the first seal member 5. The second member 6 has an abutment part 11 making abutment against the sealing fluid side O of the flange part 4 of the first seal member 5, and the abutment part suppresses deformation to the sealing fluid side O by a reinforcing part 8A arranged at the metallic ring 8 of the second seal member 6.

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 a shaft sealing portion of a tractor, a rice transplanter, or the like in which dust on the atmosphere side such as muddy water is severe.

[0002]

2. Description of the Related Art Conventionally, there is a sealing device as shown in FIG. 3, for example, which is used in a place where dust conditions on the atmospheric side such as muddy water are severe. That is, the sealing device 100 seals the space between the housing 101 and the shaft 102, which are assembled concentrically and relatively rotatably.
A sleeve portion 104 as a first seal member having a radially outward flange portion 103 on the atmosphere side A attached to the shaft 102 and an oil seal portion 105 as a second seal member attached to the housing 101 are flanged. Part 1
03 is assembled and integrated via a protective plate 106 as a protective member provided at a predetermined interval in the axial direction.

[0003] The sleeve portion 104 has a sleeve inner ring 107, and has a radially outward flange portion 103 on the atmosphere side A thereof.

The oil seal portion 105 has an oil seal inner ring 108 and a seal lip portion 109. The oil seal inner ring 108 is a cylindrical member having a radially outward outward flange 108A on the atmosphere side A and a radially inward flange 108B on the sealed fluid side O.

[0005] A seal lip portion 109 slidingly in contact with the outer peripheral surface of the cylindrical portion 107A of the sleeve inner ring 107 is fitted to the inner end of the inward flange portion 108B of the oil seal inner ring 108.
Is provided.

The seal lip portion 109 comprises a first wedge-shaped lip 110 extending from the inner end of the inward flange portion 108B to the sealed fluid side O, and a second wedge-shaped lip 111 extending to the atmosphere side A. .

The first lip 110 and the second lip 11
Garter springs 112 and 113 for applying a tightening force to the outer peripheral surface of the cylindrical portion 107A of the sleeve inner ring 107 are provided on the outer peripheral surface of the sleeve inner ring 107, respectively.

The protection plate 106 is connected to the flange 103
Is provided at a predetermined interval in the axial direction with respect to the outer peripheral portion of the protective plate 106.
It is crimped at 08D.

Further, the inner peripheral surface of the protection plate 106 has an inner peripheral bent portion 106A, which is bent toward the end surface of the flange portion 103 on the atmosphere side A.

On the other hand, a rubber-like elastic body 11 is provided on the inner peripheral surface of the sleeve inner ring 107 and the end face A on the atmosphere side of the flange portion 103.
4 is fixed. The rubber-like elastic body 114 on the atmosphere side A of the flange 103 is provided with the protective member 106 and the flange 1.
Tongue-shaped first and second rubber lips 115 and 116, which are third seal members provided between the first and second rubber pads 03, are provided at predetermined radial intervals.

The first and second rubber lips 115, 116
Extends toward the protection plate 106 and tilts inward in the radial direction, and the protection plate 1
No. 06 is formed to be in sliding contact with the end face on the sealed fluid side O.

Further, a tongue-shaped dust lip 117 is continuously provided on the rubber-like elastic body 114 near the root of the flange portion 103. The dust lip 117 extends to the atmosphere side A, is inclined outward in the radial direction, and is formed so as to slide on the inner peripheral surface of the inner peripheral bent portion 106A of the protective plate 106. Further, the rubber-like elastic body 114 facing the end face of the inner bent portion 106A of the protection plate 106 has a first rubber projection 118 protruding toward the end face. The first rubber protrusion 118 is provided between the sleeve 104 and the protection plate 106.
This is for positioning.

A second abutment against the outer peripheral end of the flange portion 103
The oil seal portion 105 has a rubber projection 119.
The second rubber projection 119 is for positioning the sleeve portion 104 and the oil seal portion 105.

A stopper 1 such as a bearing, for example, against which the sealed fluid-side O end 120 of the sleeve portion 104 abuts.
21. The stopper 121 has a sealing fluid side O
The end 120 is abutted and positioned, and the first and second rubber projections 118 and 119 and the stopper 121 prevent the sleeve 104 from moving in the thrust direction.

In the sealing device 100 having the above configuration, the dust lip 117 provided on the sleeve portion 104 prevents muddy water and the like from the atmospheric side A from entering the inside, and furthermore, the protective plate 106 and the flange portion The first and second rubber lips 115 and 116 between 103 prevent muddy water and the like from leaking into the sealed fluid side O.

[0016]

As a method for assembling the above-described prior art sealing device 100 between the housing 101 and the shaft 102, the sealing device 100 is mounted on the housing 101.
After that, there is a case where the shaft 102 is pressed into the sleeve portion 104 from the atmosphere side A and assembled. in this case,
Although the second rubber projection 119 is deformed by the press-fitting of the shaft 102 and the sleeve portion 104 cannot be positioned, the sleeve portion 104 is positioned by being abutted against the stopper 121.

However, when the stopper 121 is not used, the sleeve portion 104 is pushed into the sealed fluid side O by press fitting of the shaft 102, and the first and second rubber lips 115,
The sliding contact between the dust 116 and the dust lip 117 is reduced, and the original sealing performance cannot be exhibited.

Therefore, when the stopper 121 cannot be arranged, the sealing device 100 cannot be used.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the prior art, and an object of the present invention is to provide a sealing device capable of improving the sealing performance and expanding the applicable range of the sealing device. Is to provide.

[0020]

In order to achieve the above object, according to the present invention, there is provided a seal between a housing and a shaft which are mounted concentrically and rotatably relative to each other. A first seal member having a flange portion, a metal ring attached to the housing,
A second seal member having a seal lip portion slidingly contacting the first seal member, wherein the second seal member is a sealed fluid side of a flange portion of the first seal member. Has an abutting portion that abuts the
The abutting portion is characterized in that deformation to the sealed fluid side is suppressed by a reinforcing portion provided on a metal ring of the second seal member.

Therefore, even when the sealing device is assembled to the housing, and then the shaft is press-fitted into the first seal member from the atmosphere side, the first seal member is pushed into the sealed fluid by the press-fitting of the shaft. The first seal member can be positioned at a predetermined mounting position by preventing the abutting portion from being removed.

Therefore, the positioned butting portion is the first
In addition, even if a considerable force is applied to the abutting portion from the atmosphere side by press-fitting of the shaft, the reinforcing portion of the metal ring of the second sealing member can improve the sealing performance of the abutting portion. The rigidity is reinforced to prevent the first seal member from being displaced.

It is preferable that the abutting portion has a sliding portion made of a rubber-like elastic member having a plurality of annular projections which slide on the flange portion of the first seal member.

With this configuration, the plurality of annular projections of the sliding portion provided on the abutting portion are in sliding contact with the sealing fluid side of the flange portion of the first seal member, so that the sliding contact is made at one conventional location. Rather than improving the sealability, the abrasion resistance is improved without abrasion, and the seal durability is improved.

The metal ring of the second seal member is folded back on the sealed fluid side, and has a double cylindrical portion extending in the axial direction.
It is preferable that the reinforcing portion is continuous with the inner cylindrical portion.

Thus, the rubber-like elastic body can be fixed to the double cylindrical portion extending in the axial direction of the metal ring.
The seal between the housing and the second seal member can be sealed on the outer peripheral side, and the seal lip can be fixed on the inner peripheral side.

A protection member is provided on the atmosphere side at a predetermined axial distance from the flange portion of the first seal member and attached to the metal ring of the second seal member. Preferably, a sealing means for sealing a gap between the portion and the protection member is provided.

This makes it possible to further prevent dust such as muddy water from leaking to the sealed fluid side.

[0029]

Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. However, the dimensions of the components described in this embodiment,
The material, shape, relative arrangement, and the like are not intended to limit the scope of the present invention only to them unless otherwise specified.

FIG. 1A is a cross-sectional view showing a sealing device according to an embodiment, and FIG. 1B is a cross-sectional view showing a main portion of the sealing device of FIG. 1A.

In FIG. 1, reference numeral 1 denotes a sealing device, which is used in places where dust conditions such as muddy water on the atmosphere side A are severe, and seals between a housing 2 and a shaft 3 which are mounted concentrically and relatively rotatably. Is what you do.

The sealing device 1 has an atmosphere side A attached to the shaft 3.
A sleeve portion 5 which is a first seal member having a flange portion 4; an oil seal portion 6 which is a second seal member attached to the housing 2; A is provided with a protection plate 7 as a protection member provided in A, and the sleeve portion 5 and the oil seal portion 6 are assembled and integrated via the protection plate 7.

The sleeve section 5 has a sleeve inner ring 9. The sleeve inner ring 9 has a radially outward flange portion 4 on the atmosphere side A.

The oil seal portion 6 includes an oil seal inner ring 8 as a metal ring of the second seal member and a seal lip portion 10.
And an abutting portion 11.

The oil seal inner ring 8 has a crimping portion 8D for crimping the protection plate 7, a fixing portion 8C for positioning the protection plate 7 in contact therewith, and a double portion which is folded back on the sealing fluid side O and extends in the axial direction. It has a cylindrical portion 8B and an inward flange portion 8A as a reinforcing portion at the sealed fluid side O end.

The double cylindrical portion 8 of the oil seal inner ring 8
The rubber-like elastic body 12 is integrally baked and fixed to the inside, the outer peripheral surface, and the inward flange portion 8A of B. The outer peripheral surface side of the double cylindrical portion 8 </ b> B is a fitting portion with the housing 2.

A seal lip portion 10 is provided on the inner peripheral side of the folded double cylindrical portion 8B of the oil seal inner ring 8 in sliding contact with the outer peripheral surface of the cylindrical portion of the sleeve inner ring 9.

The seal lip portion 10 includes a first lip 13 having a wedge-shaped cross section extending toward the sealed fluid side O and a second lip 14 having a plurality of axially extending wedge-shaped sections extending toward the atmosphere side A. A garter spring 15 is provided on the outer periphery of the first lip 13 for applying a tightening force to the outer peripheral surface of the cylindrical portion of the sleeve inner ring 9.

The abutting portion 11 abuts against the flange portion 4 of the sleeve portion 5, and a plurality of annular projections 16 are provided on the abutting sliding portion. Also, the oil seal inner ring 8
8A reinforces the rigidity of the abutting portion 11.

The protective plate 7 is an annular member and its outer peripheral bent portion 7A is bent toward the sealed fluid side O, and its end is fixed to the fixed portion 8C of the oil seal inner ring 8 of the oil seal portion 6.
And is caulked to the caulked portion 8D of the inner ring 8 of the oil seal. The inner peripheral bent portion 7B of the inner periphery of the protective plate is bent toward the sealed fluid side O.

On the other hand, a rubber-like elastic body 17 is fixed to the inner peripheral surface of the sleeve inner ring 9 and the end face A on the atmosphere side of the flange portion 4. Rubber-like elastic body 17 on the atmosphere side A of flange portion 4
The first, second, and third tongue-shaped rubber lips 18, which are sealing means provided between the protection plate 7 and the flange portion 4,
Reference numerals 19 and 20 are provided at predetermined intervals in the radial direction.

The first, second, and third rubber lips 18,1
The first and second rubber lips 18 and 20 extend to the side of the protection plate 7, and the first rubber lip 18 slides on the outer bent portion 7A of the protection plate 7, and the second and third rubber lips 19 and 20 tilt inward in the radial direction. Is formed so as to be in sliding contact with the end face on the sealed fluid side O of the liquid.

A tongue-shaped dust lip 21 is provided continuously on the rubber-like elastic body 17 near the root of the flange portion 4. The dust lip 21 extends to the atmosphere side A, is inclined outward in the radial direction, and is formed so as to be in sliding contact with the inner peripheral surface of the inner peripheral bent portion 7B of the protective plate 7.

The sealing device 1 having the above-described structure removes dust such as muddy water that enters from the atmosphere side A from the dust lip 21,
Second and third rubber lips 18, 19 and 20, butting portion 1
First, the first and second lips 13 and 14 prevent entry into the sealed fluid side O.

Further, a plurality of rubber projections 1
Because of the provision of 6, the prevention of dust intrusion can be further enhanced.

Since the plurality of rubber projections 16 of the abutting portion 11 are in sliding contact with the sealing fluid side O of the flange portion 4, they do not wear as compared with the conventional sliding contact in one place, and the wear resistance is improved. Seal durability is improved.

As a method for assembling the sealing device 1 having the above structure between the housing 2 and the shaft 3, a case where the sealing device 1 is assembled to the housing 2 and then the shaft 3 is pressed into the sleeve portion 5 from the atmosphere side A and assembled. Even axis 3
The pressing portion 11 prevents the sleeve portion 5 from being pushed into the sealed fluid side O by the press-fitting, and the sleeve portion 5 can be positioned at a predetermined mounting position.

Further, the abutting portion 11 is formed by press-fitting the shaft 3.
Even if a considerable force is applied from the atmosphere side A, the inward flange portion 8A of the oil seal inner ring 8 reinforces the rigidity of the abutting portion 11, thereby preventing displacement.

Therefore, since the sealing device 1 can be used without the need for a stopper such as a bearing, the usable range of the sealing device 1 can be expanded.

In the sealing device 1 of the present embodiment, unlike the prior art, the outward flange portion of the oil seal inner ring that comes into contact with the housing 2 is not provided, and a portion having a diameter larger than the inner diameter of the housing is provided in the sealing device. Therefore, the usable range of the sealing device 1 can also be expanded.

In the present embodiment, the third rubber lip 20 is provided to provide further space for setting the rubber lip as the sealing means to further improve the sealing performance. May or may not be provided, and a fourth rubber lip or the like may be further provided.

FIG. 2 shows, as another example of the sealing device according to the present embodiment, a sealing device having a small space for setting a rubber lip. Thus, the first and second rubber lips 18, 1
The present invention can be applied to a case where only 9 is provided or a case where the rubber lip is further reduced.

[0053]

As described above, according to the present invention, the second sealing member has the abutting portion abutting on the sealing fluid side of the flange portion of the first sealing member, and the abutting portion is the second sealing member. When the deformation to the sealed fluid side is suppressed by the reinforcing portion provided on the metal ring, the sealing device is assembled to the housing, and then the shaft is pressed into the first seal member from the atmosphere side and assembled. Even if there is, the abutting portion can prevent the first seal member from being pushed into the sealed fluid side by press fitting of the shaft, and the first seal member can be positioned at a predetermined mounting position.

Therefore, the positioned abutting portion improves the sealing performance, and even if a considerable force is applied to the abutting portion from the atmosphere by press-fitting the shaft, the metal ring of the second seal member is reinforced. The part reinforces the rigidity of this abutting part, suppressing deformation to the sealed fluid side and preventing displacement, so that the sealing device can be used without the need for a stopper such as a bearing, and the use of the sealing device Possible applications can be expanded.

The abutting portion has a sliding portion made of a rubber-like elastic member having a plurality of annular protrusions which slide on the flange portion of the first seal member. Since the plurality of annular projections are in sliding contact with the sealing fluid side of the flange portion of the first seal member, the sealing performance is improved and the abrasion resistance is improved as compared with the conventional one in which sliding contact is made at one place. And the durability of the seal is improved.

The metal ring of the second seal member is folded back on the sealed fluid side and has a double cylindrical portion extending in the axial direction. When the reinforcing portion is continuous with the inner cylindrical portion, the double cylindrical metal ring is formed. Since the rubber-like elastic body can be fixed to the portion, the space between the housing and the second seal member can be sealed on the outer peripheral side, and the seal lip can be fixed on the inner peripheral side.

Attached to the metal ring of the second seal member,
By providing a protection member on the atmosphere side with a predetermined gap in the axial direction from the flange portion of the first seal member, and providing sealing means for sealing a gap between the flange portion of the first seal member and the protection member, It is possible to further prevent dust such as muddy water from leaking to the sealed fluid side.

[Brief description of the drawings]

FIG. 1A is a cross-sectional view showing a sealing device according to an embodiment, and FIG. 1B is a cross-sectional view of a main part showing an S region of FIG. 1A in an enlarged manner.

FIG. 2 is a sectional view showing another sealing device according to the embodiment.

FIG. 3 is a cross-sectional view showing a conventional sealing device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Sealing device 2 Housing 3 Shaft 4 Flange part 5 Sleeve part 6 Oil seal part 7 Protective plate 7A Outer bending part 7B Inner bending part 8 Oil seal inner ring 8A Inward flange part 8B Double cylindrical part 8C Fixed part 8D Part 9 Sleeve inner ring 10 Seal lip part 11 Abutment part 12 Rubber-like elastic body part 13 First lip 14 Second lip 15 Garter spring 16 Rubber protrusion 17 Rubber-like elastic body part 18 First rubber lip 19 Second rubber lip 20 Third Rubber lip 21 dust lip

Claims (4)

[Claims] A first seal member attached to the shaft, the first seal member having a flange portion on the atmosphere side, the first seal member being attached to the shaft, and being attached to the housing; In a sealing device having a metal ring and a second seal member having a seal lip portion that slides on the first seal member, the second seal member is a flange portion of the first seal member. Abutting portions abutting against the sealed fluid side, wherein the abutting portions are suppressed from being deformed toward the sealed fluid side by reinforcing portions provided on the metal ring of the second seal member. Sealing device. 2. The device according to claim 1, wherein the abutting portion includes a sliding portion made of a rubber-like elastic member having a plurality of annular protrusions that slide on the flange portion of the first seal member. Sealing device. 3. The metal ring of the second sealing member is folded back on the sealing fluid side, has a double cylindrical portion extending in the axial direction, and the reinforcing portion is connected to the atmosphere side of the inner cylindrical portion. The sealing device according to claim 1 or 2, wherein: 4. A first sealing member attached to a metal ring of the second sealing member and provided with a protection member on the atmosphere side at a predetermined axial distance from a flange portion of the first sealing member. 3. A sealing means for sealing a gap between said flange portion and said protection member.
The sealing device according to claim 1.