CN110073131B

CN110073131B - Sealing device

Info

Publication number: CN110073131B
Application number: CN201780077016.4A
Authority: CN
Inventors: 菊地健一
Original assignee: Nok Corp
Current assignee: Nok Corp
Priority date: 2016-12-21
Filing date: 2017-12-19
Publication date: 2020-09-22
Anticipated expiration: 2037-12-19
Also published as: JP7065037B2; CN110073131A; WO2018117100A1; JPWO2018117100A1

Abstract

Provided is a sealing device capable of further reducing the intrusion of foreign matter into the internal space of an apparatus. A sealing device for sealing lubricant in an internal space of a device in the internal space of the device is provided with: a 1 st sealing member fixed to an inner member of two members that relatively rotate; and a 2 nd sealing member fixed to an inner surface of the hole of the outer member of the two members rotating relative to each other, slidably contacting the 1 st sealing member. The 2 nd sealing member includes an outer cylindrical body fixed to the hole, and a lip portion slidably contacting the 1 st sealing member. The 1 st seal member includes a sleeve fixed to the rotary shaft, and a flange integrally connected to an atmosphere-side end portion of the sleeve and radially extending outward thereof. The outer end edge of the flange is formed with an outer cylindrical portion concentric with the hole. The outer peripheral surface of the outer cylindrical portion is formed with an annular projection which is slidable on the inner peripheral surface of the outer cylindrical body of the 2 nd seal member and is in sealing contact with the inner peripheral surface of the outer cylindrical body over the entire circumference.

Description

Sealing device

Technical Field

The present invention relates to a sealing device for an apparatus having two members that rotate relative to each other.

Background

Conventionally, as such a sealing device, for example, as described in patent document 1, there is known a sealing structure including: one of two members fixed to relative rotation, for example, a rotary seal member called a slinger fixed to a rotary shaft; and a stationary seal member fixed to the other of the two members that rotate relative to each other, for example, to an inner surface of a shaft hole of the housing. Such sealing devices are used for sealing lubricant, for example grease, in the interior of the apparatus. Since the rotary seal member is provided with a flange that prevents or reduces intrusion of mud and dust into the interior space of the equipment from the atmosphere, such a seal device is used in equipment used in an environment where mud and dust are abundant, such as a bogie of a railway vehicle, a pallet frame of a sintering machine, a construction machine, a counter balance suspension of a truck, and an agricultural machine.

Documents of the prior art

Patent document

Patent document 1: japanese patent No. 4978074

Disclosure of Invention

Technical problem to be solved by the invention

In a device provided with such a sealing device, it is desirable to reduce the intrusion of foreign matter such as mud, muddy water, or dust into the internal space of the device as much as possible.

Accordingly, an object of the present invention is to provide a sealing device capable of further reducing intrusion of foreign matter into an internal space of an apparatus.

Means for solving the technical problem

In order to solve the above problem, a sealing device according to the present invention includes: a 1 st sealing member fixed to an inner member of two members that relatively rotate; and a 2 nd sealing member fixed to an inner face of the hole of the outer member of the two members that relatively rotate, slidably contacting the 1 st sealing member; the sealing device seals lubricant in an internal space of an apparatus in the internal space of the apparatus, wherein the 2 nd sealing member includes an outer cylindrical body fixed to the hole and a lip portion slidably contacting the 1 st sealing member, the 1 st sealing member includes a sleeve fixed to the inner member and a flange integrally connected to an atmosphere-side end portion of the sleeve and radially expanding outward, an outer cylindrical portion concentric with the hole is formed at an outer end edge of the flange, and an annular protrusion is formed on an outer circumferential surface of the outer cylindrical portion, the annular protrusion being slidable on an inner circumferential surface of the outer cylindrical body of the 2 nd sealing member and sealingly contacting an entire circumference of the inner circumferential surface of the outer cylindrical body.

In this sealing device, an annular projection is formed on the outer peripheral surface of an outer cylindrical portion formed at the outer end edge of a flange of a 1 st seal member so as to be slidable on the inner peripheral surface of an outer cylindrical body of a 2 nd seal member, and the projection is in sealing contact with the entire inner peripheral surface of the outer cylindrical body. Therefore, on the atmosphere side of the sealing device, the gap between the 1 st seal member and the 2 nd seal member is closed.

In the sealing device of one aspect of the present invention, the protrusion is formed as a plurality of ridges in a direction parallel to the axial direction of the hole. In this way, the plurality of ridges are present in the direction parallel to the axial direction of the hole, and thereby the plurality of steps prevent the entry of foreign matter from the atmosphere side.

In the sealing device according to one aspect of the present invention, the outer cylindrical portion of the 1 st sealing member extends from the outer end edge of the flange toward the atmosphere, and the plurality of ridges have a diameter that decreases from the atmosphere toward the device internal space. In this structure, the bulge having a large diameter on the atmosphere side is first pressed against the inner circumferential surface of the outer cylindrical body of the 2 nd sealing member by a strong force. When the bulge is worn, other bulges having a small diameter on the side of the inner space of the device are pressed by a strong force. Thus, the seal has a long life even if there is local wear.

In the sealing device according to one aspect of the present invention, the plurality of different annular protrusions are disposed at intervals from each other in the outer cylindrical portion of the first sealing member 1 in a direction parallel to the axial direction of the hole. In this structure, a plurality of ridges can be easily provided in a direction parallel to the axial direction of the hole, as compared with a case where one protrusion is formed spirally.

Effects of the invention

In the present invention, a projection slidable on the inner peripheral surface of the outer cylindrical body of the 2 nd seal member is formed on the outer peripheral surface of the outer cylindrical portion formed at the outer end edge of the flange of the 1 st seal member, and the projection is in sealing contact with the entire periphery of the inner peripheral surface of the outer cylindrical body. Therefore, the gap between the 1 st seal member and the 2 nd seal member is closed on the atmosphere side of the sealing device, and intrusion of foreign matter into the apparatus internal space from the atmosphere side can be further reduced.

Drawings

FIG. 1 is a cross-sectional view of a sealing device according to an embodiment of the present invention;

FIG. 2 is a cross-sectional view of a rotating seal member of the sealing device of FIG. 1;

FIG. 3 is a cross-sectional view of a stationary seal member of the seal of FIG. 1;

fig. 4 is a partially enlarged sectional view of the rotary seal member.

Detailed Description

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

Fig. 1 is a view of an embodiment of the present invention, showing a sealing device for an apparatus having two members that rotate relative to each other. In the present specification, "rotation" means not only a rotational motion of 360 ° or more but also a rotational motion in a range of less than 360 °, and also includes a rotational motion in one direction and in the opposite direction in a range of less than 360 °.

The sealing device 1 seals between a rotating shaft (radially inner member) 4 and an inner surface of a shaft hole 6 of a housing (radially outer member) 5 into which the rotating shaft 4 is inserted, and prevents or reduces leakage of a fluid from an apparatus internal space S to the atmosphere a. The rotary shaft 4 has a cylindrical shape, the shaft hole 6 has a circular cross section, and the seal device 1 has a substantially annular shape, and only the left side portion of the shaft hole 6 and the seal device 1 is shown in fig. 1.

The seal device 1 is an assembly of a rotary seal member 8, called a slinger, fixed to the rotary shaft 4 and rotating integrally with the rotary shaft 4, and a stationary seal member 10 fixed to the shaft hole 6. The rotary seal member 8 seals lubricant in the apparatus interior space S in cooperation with the stationary seal member 10. The rotary seal member 8 is fitted to the fixed seal member 10, and when a large force is applied in the axial direction of the seal device 1, the fitting can be released and removed.

The rotary seal member 8 includes: a sleeve 12 fixed to the rotary shaft 4; and a flange 14 integrally connected to an end portion of the sleeve 12 on the atmosphere a side and radially extending outward therefrom. The fixing manner of the rotating shaft 4 and the sleeve 12 is not limited, and may be, for example, an interference fit. The rotary seal member 8 has a double structure, and includes: the elastic body is, for example, an elastic ring 16 formed of an elastic body, and a rigid body, for example, a metal reinforcing ring 18, which is in close contact with the elastic ring 16 and reinforces the elastic ring 16.

As shown in fig. 2, the sleeve 12 includes: an inner cylindrical portion 16a which is a part of the elastic ring 16 and which is in close contact with the rotary shaft 4; and an outer cylindrical portion 18a which is a part of the reinforcing ring 18 and is fixed to the outer periphery of the inner cylindrical portion 16 a. The flange 14 includes: an elastic flange portion 16b which is a part of the elastic ring 16 and is disposed on the atmosphere a side; and a rigid flange part 18b which is a part of the reinforcing ring 18, is disposed on the equipment internal space S side, and is fixed to the elastic flange part 16 b.

As shown in fig. 3, the fixed seal member 10 also has a double structure including: an elastomer, such as an elastomeric ring 20; and a rigid body for reinforcing the elastic ring 20, such as a metal reinforcing ring 22. Most of the reinforcing ring 22 is embedded in the elastic ring 20 and closely attached to the elastic ring 20.

As shown in fig. 1, the reinforcing ring 22 for fixing the sealing member 10 includes: a cylindrical portion 22a concentrically arranged in the shaft hole 6; an L-shaped curved portion 22b disposed radially inward of the cylindrical portion 22 a; and a circular plate-shaped connecting portion 22c connecting the cylindrical portion 22a and the curved portion 22 b. The reinforcing ring 22 for fixing the sealing member 10 further includes: a large-diameter cylindrical portion 22d having a larger diameter than the cylindrical portion 22a concentrically arranged in the shaft hole 6; and a connecting portion 22e connecting the cylindrical portion 22a and the large-diameter cylindrical portion 22d, and having a truncated cone-shaped contour. The large-diameter cylindrical portion 22d is disposed on the atmosphere a side of the cylindrical portion 22 a.

The elastic ring 20 for fixing the seal member 10 includes an outer cylindrical portion 20a disposed outside the cylindrical portion 22 a. The outer cylindrical portion 20a is an outer seal portion fixed to the shaft hole 6. The fixing method is not limited, and may be an interference fit, for example. The reinforcing ring 22 applies a radially outward force to the outer cylindrical portion 20a of the elastic ring 20, and strongly presses the outer cylindrical portion 20a against the shaft hole 6.

The outer cylindrical portion 20a of the elastic ring 20, and the cylindrical portion 22a, the connecting portion 22e, and the large-diameter cylindrical portion 22d of the reinforcing ring 22 constitute an outer cylindrical body 26 fixed to the shaft hole 6.

The elastic ring 20 that fixes the seal member 10 includes an inner cylindrical portion 20b concentric with the outer cylindrical portion 20 a. Around the inner cylindrical portion 20b, a garter spring 30 for compressing the inner cylindrical portion 20b radially inward is wound. The inner cylindrical portion 20b is formed with a receiving groove 32 (refer to fig. 3) that receives the chucking spring 30.

The inner cylindrical portion 20b of the elastic ring 20 that fixes the seal member 10 includes: a sealing lip 36, a dust lip 38, and a dust lip 40. The seal lip portion 36 is an annular protrusion that protrudes inward from the inner cylindrical portion 20b and is continuous in the circumferential direction. The seal lip 36 is in sealing contact with the outer peripheral surface of the sleeve 12 of the rotary seal member 8, and prevents or reduces leakage of fluid from the apparatus internal space S to the atmosphere a side. When the rotary seal member 8 rotates simultaneously with the rotary shaft 4, the outer peripheral surface of the sleeve 12 slides against the seal lip 36. The garter spring 30 applies a force to the seal lip 36 to press the seal lip 36 against the rotary shaft 4. Fig. 1 shows a state in which the seal lip 36 and other lips are pressed toward the rotary seal member 8 and deformed, and fig. 3 shows a state in which these lips are not elastically deformed.

The

dust lip portions

38 and 40 extend obliquely from the inner cylindrical portion 20b toward the atmosphere a and radially inward. The tips of the

dust lips

38, 40 are in sealing contact with the outer peripheral surface of the sleeve 12 of the rotary seal member 8, and when the rotary seal member 8 rotates together with the rotary shaft 4, the outer peripheral surface of the sleeve 12 slides with respect to the

dust lips

38, 40.

The elastic ring 20 for fixing the seal member 10 includes a dust lip 42. The dust lip 42 extends from the vicinity of the inner cylindrical portion 20b toward the atmosphere a, curves, and further extends obliquely outward in the radial direction and toward the atmosphere a. The tip of the dust lip 42 contacts the rigid flange 18b of the flange 14 of the rotary seal member 8, and when the rotary seal member 8 rotates together with the rotary shaft 4, the rigid flange 18b slides with respect to the dust lip 42.

The dust-

proof lips

38, 40, and 42 mainly function to prevent foreign matters (mud, muddy water, and dust) from entering the equipment internal space S from the atmosphere a. The

dust lip portions

38, 40, 42 also prevent the lubricant from flowing out from the equipment internal space S to the atmosphere a side.

In this embodiment, the outer end edge of the rigid flange portion 18b of the flange 14 of the rotary seal member 8 is formed with an outer cylindrical portion 44 concentric with the shaft hole 6. The outer cylindrical portion 44 extends from the outer end edge of the flange 14 toward the atmosphere a.

A plurality of (5 in this embodiment) protrusions 46 are formed on the outer peripheral surface of the outer cylindrical portion 44. These protrusions 46 are arranged at intervals from each other in the outer cylindrical portion 44 in a direction parallel to the axial direction of the shaft hole 6. These projections 46 project radially outward from the outer circumferential surface of the outer cylindrical portion 44, and each projection 46 is formed in a circumferentially continuous ring shape. As shown in fig. 2, each protrusion 46 has a substantially semicircular contour in a state in which it is not elastically deformed, but the contour of the protrusion 46 is not limited to the illustrated contour, and may have various contours.

As shown in fig. 1, at least 1 of these projections 46 is slidable on the inner peripheral surface of the large-diameter cylindrical portion 22d of the outer cylindrical body 26 of the fixed sealing member 10, and is in sealing contact with the entire circumference of the inner peripheral surface of the large-diameter cylindrical portion 22 d. The other projections 46 may not contact the inner peripheral surface of the large-diameter cylindrical portion 22 d.

In this sealing device 1, an annular projection 46 slidable on the inner peripheral surface of the large-diameter cylindrical portion 22d of the outer cylindrical body 26 of the fixed sealing member 10 is formed on the outer peripheral surface of the outer cylindrical portion 44 formed at the outer end edge of the flange 14 of the rotary sealing member 8, and the projection 46 is in sealing contact with the entire inner peripheral surface of the large-diameter cylindrical portion 22d of the outer cylindrical body 26. Therefore, the gap between the rotary seal member 8 and the fixed seal member 10 is closed on the atmosphere a side of the seal device 1, and intrusion of foreign matter into the apparatus internal space S from the atmosphere a side can be reduced.

In order to reduce the intrusion of foreign matter into the apparatus internal space S from the atmosphere a side, a protective cover may be attached to the atmosphere a side of the sealing device 1. However, since the sealing device 1 has high characteristics of preventing the intrusion of foreign matter, such a protective cover may not be provided.

The projections 46 are formed as a plurality of ridges in a direction parallel to the axial direction of the shaft hole 6 (i.e., in the cross-section shown in fig. 1 and 2). In this embodiment, each protrusion 46 corresponds to a bump. In this embodiment, the plurality of ridges are wave-shaped. Since the plurality of ridges are present in the direction parallel to the axial direction of the shaft hole 6, the plurality of steps prevent foreign matter from entering from the atmosphere a side.

Fig. 4 is an enlarged partial cross-sectional view of the rotary seal member 8 of the sealing device 1 of fig. 1. Hatching is omitted in fig. 4. As shown in fig. 4, the outer cylindrical portion 44 of the rotary seal member 8 extends from the outer end edge of the flange 14 toward the atmosphere a, and a plurality of annular projections 46 (indicated by 46a to 46e in fig. 4) have a diameter that decreases from the atmosphere a toward the device internal space S. That is, the projection 46a on the side closest to the atmosphere a has the largest diameter Da even in a state of being in contact with the inner peripheral surface of the large-diameter cylindrical portion 22d of the outer cylindrical body 26 of the fixed sealing member 10. The atmosphere a side 2 nd projection 46b has the 2 nd largest diameter Db. The atmosphere a side 3 rd projection 46c has the 3 rd major diameter Dc. The atmosphere a side 4 th projection 46d has the 4 th major diameter Dd. The projection 46e closest to the apparatus internal space S side has the smallest diameter De.

In this structure, the projection 46a having the maximum diameter Da on the atmosphere a side is first pressed against the inner peripheral surface of the large-diameter cylindrical portion 22d of the outer cylindrical body 26 of the fixed sealing member 10 by a strong force. If the projection 46a is worn, the other projection 46b having the next larger diameter Db on the device internal space S side is pressed against the inner peripheral surface of the large diameter cylindrical portion 22d with a strong force. If the projection 46b is worn, the other projection 46c having the next larger diameter Dc on the side of the device internal space S is pressed against the inner peripheral surface of the larger diameter cylindrical portion 22d by a strong force. If the projection 46c is worn, the other projection 46d having the next larger diameter Dd on the device internal space S side is pressed against the inner peripheral surface of the large diameter cylindrical portion 22d with a strong force. If the projection 46d is worn, the other projection 46e having the next larger diameter De on the side of the device internal space S is pressed against the inner peripheral surface of the large diameter cylindrical portion 22d with a strong force. Therefore, the sealing device 1 has a long life even if there is partial wear. That is, the intrusion of foreign matter can be prevented for a long period of time.

In this embodiment, in a state where the rotary seal member 8 and the fixed seal member 10 are combined (fig. 1), the plurality of projections 46 have a diameter that becomes smaller from the atmosphere a side toward the device internal space S side. In order to reliably form this structure, the outer cylindrical portion 44, particularly the outer circumferential surface thereof, extends obliquely from the outer end edge of the flange 14 toward the atmosphere a and radially outward in a state where the rotary seal member 8 is not combined with the fixed seal member 10 (fig. 2). In a state (fig. 1) in which the rotary seal member 8 and the fixed seal member 10 are combined, the projection 46 having the maximum diameter on the atmosphere a side is restricted by the large-diameter cylindrical portion 22d of the fixed seal member 10, and the inclination angle of the outer cylindrical portion 44, particularly the outer peripheral surface thereof, with respect to the axis of the shaft hole 6 is made small, but since the outer cylindrical portion 44 is originally inclined, a configuration in which the plurality of projections 46 have a smaller diameter from the atmosphere a side to the device internal space S side can be maintained even after elastic deformation.

As a modification, in the case where one projection is formed spirally, a raised portion that contacts the inner peripheral surface of the large-diameter cylindrical portion 22d may be changed by local friction. However, in this embodiment, since the plurality of different annular protrusions 46 are disposed at intervals in the outer cylindrical portion 44 of the rotary seal member 8 in the direction parallel to the axial direction of the shaft hole 6, a plurality of ridges can be easily provided in the direction parallel to the axial direction of the shaft hole 6, as compared with a case where one protrusion 46 is formed spirally.

As described above, various measures for preventing or reducing the intrusion of foreign matter into the apparatus internal space S from the atmosphere a side are implemented in the sealing device 1. Therefore, the sealing device 1 can exhibit a good sealing function even in equipment used in an environment with a large amount of mud or dust, such as a bogie of a railway vehicle, a pallet frame of a sintering machine, a construction machine, a balance suspension of a truck, and an agricultural machine (a cultivator, a tractor, a rice transplanter, etc.), for example. However, the use of the sealing device 1 is not limited to this type of apparatus, and may be applied to other apparatuses.

The space 50 between the seal lip 36 and the dust lip 38 (see fig. 1), the space 52 between the

dust lips

38, 40, and the space 54 between the

dust lips

40, 42 may also be provided with a lubricant. In this case, the wear resistance of these lips will be improved.

Other variants

While the embodiments of the present invention have been described above, the above description is not intended to limit the present invention, and various modifications including deletion, addition, and substitution of constituent elements are conceivable within the technical scope of the present invention.

For example, the shape and number of the lips for fixing the seal member 10 are not limited to the above.

The number of the projections 46 is not limited to the embodiment.

In the above embodiment, the shaft 4 is a rotating shaft, and the housing provided with the shaft hole 6 is a stationary member. However, the present invention is not limited to the above embodiment, and can be applied to sealing between two members that rotate relative to each other. For example, it is also possible that the shaft 4 (and the sealing member 8) is stationary, the housing (and the sealing member 10) rotates around it, or both the shaft 4 and the housing rotate.

Description of the symbols

A-atmosphere, S-apparatus inner space, 1-seal, 4-rotation axis (inner member), 5-housing (outer member), 6-shaft hole (hole), 8-rotation seal member (1 st seal member), 10-stationary seal member (2 nd seal member), 12-sleeve, 14-flange, 16-elastic ring, 16 a-inner cylindrical portion, 16 b-elastic flange portion, 18-reinforcing ring, 18 a-outer cylindrical portion, 18 b-rigid flange portion, 20-elastic ring, 20 a-outer cylindrical portion, 20 b-inner cylindrical portion, 22-reinforcing ring, 22 a-cylindrical portion, 22 b-curved portion, 22 c-connecting portion, 22 d-large diameter cylindrical portion, 22 e-connecting part, 26-outer cylinder, 30-garter spring, 32-receiving groove, 36-sealing lip, 38, 40, 42-dust lip, 44-outer cylinder, 46-protrusion, 50, 52, 54-space

Claims

1. A sealing device is provided with: a 1 st sealing member fixed to an inner member of two members that relatively rotate; and a 2 nd sealing member fixed to an inner face of the hole of the outer member of the two members that relatively rotate, slidably contacting the 1 st sealing member; the sealing device seals lubricant in the interior space of the apparatus, characterized in that,

the 2 nd sealing member includes an outer cylindrical body fixed to the hole and a lip portion slidably contacting the 1 st sealing member,

the 1 st seal member includes a sleeve fixed to the inner member, and a flange integrally connected to an atmosphere-side end portion of the sleeve and radially extending outward thereof,

an outer end edge of the flange is formed with an outer cylindrical portion concentric with the hole, an outer circumferential surface of the outer cylindrical portion being formed with an annular projection slidable on an inner circumferential surface of the outer cylindrical body of the 2 nd seal member and in sealing contact with the inner circumferential surface of the outer cylindrical body over an entire circumference thereof,

the protrusion is formed as a plurality of ridges in a direction parallel to the axial direction of the hole,

the outer cylindrical portion of the 1 st seal member extends to the atmosphere side from the outer end edge of the flange,

the plurality of ridges have a diameter that becomes smaller and smaller from the atmospheric side toward the device internal space side.

2. The sealing device according to claim 1, wherein a plurality of different annular protrusions are arranged at intervals from each other in a direction parallel to an axial direction of the hole in the outer cylindrical portion of the 1 st sealing member.