WO2018117100A1 - Sealing device - Google Patents

Abstract

[Problem] To provide a sealing device which is capable of further reducing infiltration of foreign matter into an internal space of an apparatus. [Solution] A sealing device for sealing, in an internal space of an apparatus, a lubricant for said internal space of the apparatus is provided with: a first seal member which is fixed to an inner member among two members which rotate relative to each other; and a second seal member which is fixed to the inner surface of a hole in an outer member among the two members which rotate relative to each other, said second seal member being in contact with the first seal member such that the first seal member is capable of sliding. The second seal member is provided with: an outer cylindrical body which is fixed in the hole; and a lip part which is in contact with the first seal member so as to be capable of sliding. The first seal member is provided with: a sleeve which is fixed to a rotational shaft; and a flange which is integrally connected to an atmosphere-side end of the sleeve, and which extends radially outward. An outer cylindrical part having the same centre as the hole is formed on the outer edge of the flange. Annular protrusions which are capable of sliding on the inner circumferential surface of the outer cylindrical body of the second seal member, and which are in contact with and seal the whole circumference of the inner circumferential surface of the outer cylindrical body are formed on the outer circumferential surface of the outer cylindrical part.

Description

Sealing device

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

Conventionally, as a sealing device of this type, for example, as described in Patent Document 1, one of two relatively rotating members, for example, a rotary seal member called a slinger fixed to a rotating shaft, and two members rotating relatively On the other hand, for example, a sealing structure having a fixed seal member fixed to an inner surface of a shaft hole of a housing is known. Such a sealing device is used to seal a lubricant, for example grease, in the interior space of the device. The rotary seal member is provided with a flange, and this flange prevents or reduces intrusion of mud and dust from the atmosphere side into the internal space of the equipment. For example, a railway vehicle carriage, a sintered pallet carriage, a construction machine, a truck Such sealing devices are used in equipment used in mud or dusty environments such as trunnion suspensions, agricultural machinery.

Japanese Patent No. 4979744

For devices having this type of sealing device, it is desirable to reduce as much as possible the entry of foreign matter such as mud, muddy water or dust into the internal space of the device.

Therefore, an object of the present invention is to provide a sealing device that can further reduce the intrusion of foreign matter into the internal space of the device.

In order to solve the above-described problems, a sealing device according to the present invention includes a first seal member fixed to an inner member of two relatively rotating members, and a hole in an outer member of the two relatively rotating members. And a second seal member that is slidably contacted with the first seal member, and seals the lubricant in the device internal space to the device internal space, The seal member 2 includes an outer cylindrical body fixed to the hole and a lip portion that slidably contacts the first seal member, and the first seal member includes the inner seal member. A sleeve fixed to the member, and a flange that is integrally connected to an end portion on the atmosphere side of the sleeve and radially spreads outside the sleeve, and an outer edge of the flange is concentric with the hole. An outer cylindrical portion is formed, and the outer cylindrical portion An annular protrusion is formed on the peripheral surface so as to be slidable on the inner peripheral surface of the outer cylindrical body of the second seal member and hermetically contact the entire inner peripheral surface of the outer cylindrical body. It is characterized by being.

In this sealing device, an annular protrusion slidable on the outer peripheral surface of the outer cylindrical portion formed on the outer edge of the flange of the first seal member and on the inner peripheral surface of the outer cylindrical body of the second seal member. Is formed, and the protrusion is in sealing contact with the inner peripheral surface of the outer cylindrical body over the entire periphery. Therefore, the gap between the first seal member and the second seal member is closed on the atmosphere side of the sealing device.

In the sealing device according to an aspect of the present invention, the protrusion is formed to form a plurality of ridges in a direction parallel to the axial direction of the hole. Thus, the presence of a plurality of ridges in the direction parallel to the axial direction of the hole prevents foreign substances from entering from the atmosphere in a plurality of stages.

In the sealing device according to the aspect of the present invention, the outer cylindrical portion of the first seal member extends from the outer end edge of the flange toward the atmosphere side, and the plurality of bulges are formed from the atmosphere side. It has a smaller diameter toward the inner space of the device. In this configuration, the bulge having a large diameter on the atmosphere side is first pressed against the inner peripheral surface of the outer cylindrical body of the second seal member with a strong force. When the ridge is worn, another ridge having a small diameter on the device internal space side is pressed with a strong force. Thus, the sealing device has a long life despite local wear.

In the sealing device according to one aspect of the present invention, a plurality of separate annular protrusions are disposed on the outer cylindrical portion of the first seal member so as to be spaced from each other in a direction parallel to the axial direction of the hole. Has been. In this configuration, it is possible to easily provide a plurality of ridges in a direction parallel to the axial direction of the hole, rather than forming one protrusion in a spiral shape.

In the present invention, a slidable protrusion is formed on the outer peripheral surface of the outer cylindrical portion formed on the outer edge of the flange of the first seal member on the inner peripheral surface of the outer cylindrical body of the second seal member. The protrusion is in sealing contact with the inner peripheral surface of the outer cylindrical body over the entire circumference. Therefore, on the atmosphere side of the sealing device, the gap between the first seal member and the second seal member is closed, and the entry of foreign matter from the atmosphere side into the device internal space can be further reduced.

It is sectional drawing of the sealing device which concerns on embodiment of this invention. It is sectional drawing of the rotation sealing member of the sealing device of FIG. It is sectional drawing of the fixed sealing member of the sealing device of FIG. It is sectional drawing to which some rotation seal members were expanded.

Embodiments according to the present invention will be described below with reference to the accompanying drawings.
FIG. 1 is a diagram according to an embodiment of the present invention, and shows a sealing device used in an apparatus having two members that rotate relative to each other. In this specification, the term “rotation” includes not only a motion exceeding 360 ° but also a motion rotating within a range of less than 360 °, and further including a motion rotating in one direction and the reverse direction within a range of less than 360 °. .

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

The sealing device 1 is an assembly that is a combination of a rotary seal member 8 called a slinger that is fixed to the rotary shaft 4 and rotates integrally with the rotary shaft 4, and a fixed seal member 10 that is fixed to the shaft hole 6. The rotary seal member 8 and the fixed seal member 10 cooperate to seal the lubricant in the device internal space S. The rotary seal member 8 is fitted to the fixed seal member 10. When a large force is applied along the axial direction of the sealing device 1, the fitting is released and can be removed.

The rotary seal member 8 has a sleeve 12 fixed to the rotary shaft 4 and a flange 14 that is integrally connected to the end of the sleeve 12 on the atmosphere A side and radially spreads outside thereof. The method of fixing the rotating shaft 4 and the sleeve 12 is not limited, but may be an interference fit, for example. The rotary seal member 8 has a double structure, and includes an elastic ring 16 formed of an elastic body, for example, an elastomer, 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 is a part of the elastic ring 16 and is fixed to the outer periphery of the inner cylindrical part 16 a that is a part of the inner cylindrical part 16 a that is in close contact with the rotating shaft 4 and a reinforcing ring 18. The outer cylindrical portion 18a. The flange 14 is a part of the elastic ring 16 and is disposed on the atmosphere A side, and the flange 14 is a part of the reinforcing ring 18 and is disposed on the equipment internal space S side and is fixed to the elastic flange part 16b. And a rigid flange portion 18b.

As shown in FIG. 3, the fixed seal member 10 also has a double structure, and includes an elastic ring 20 formed of an elastic body, for example, an elastomer, and a rigid body that reinforces the elastic ring 20, for example, a metal reinforcing ring 22. Have. Most of the reinforcing ring 22 is embedded in the elastic ring 20 and is in close contact with the elastic ring 20.

As shown in FIG. 1, the reinforcing ring 22 of the fixed seal member 10 includes a cylindrical portion 22a disposed concentrically with the shaft hole 6, and an L-shaped bent portion 22b disposed radially inward of the cylindrical portion 22a. And a disc-shaped connecting portion 22c for connecting the cylindrical portion 22a and the bent portion 22b. The reinforcing ring 22 of the fixed seal member 10 further includes a large-diameter cylindrical portion 22d concentrically arranged in the shaft hole 6 and having a larger diameter than the cylindrical portion 22a, and a truncated cone connecting the cylindrical portion 22a and the large-diameter cylindrical portion 22d. And a connecting portion 22e having a contour. The large-diameter cylindrical portion 22d is disposed closer to the atmosphere A than the cylindrical portion 22a.

The elastic ring 20 of the fixed seal member 10 has an outer cylindrical portion 20a disposed outside the cylindrical portion 22a. The outer cylindrical portion 20 a is an outer seal portion that is fixed to the shaft hole 6. The fixing method is not limited, but may be an interference fit, for example. The reinforcing ring 22 applies a force toward the outer side in the radial direction to the outer cylindrical portion 20 a of the elastic ring 20, and firmly presses the outer cylindrical portion 20 a 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 that is fixed to the shaft hole 6.

The elastic ring 20 of the fixed seal member 10 has an inner cylindrical portion 20b concentric with the outer cylindrical portion 20a. A garter spring 30 for compressing the inner cylindrical portion 20b radially inward is wound around the inner cylindrical portion 20b. A receiving groove 32 (see FIG. 3) for receiving the garter spring 30 is formed in the inner cylindrical portion 20b.

The inner cylindrical portion 20b of the elastic ring 20 of the fixed seal member 10 has a seal lip portion 36, a dust lip portion 38, and a dust lip portion 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 portion 36 is in sealing contact with the outer peripheral surface of the sleeve 12 of the rotary seal member 8 to prevent or reduce fluid leakage from the device internal space S to the atmosphere A side. 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 seal lip portion 36. The garter spring 30 applies a force for pressing the seal lip portion 36 against the rotating shaft 4 to the seal lip portion 36. FIG. 1 shows a state in which the seal lip portion 36 and other lip portions are pressed and deformed against the rotary seal member 8, and FIG. 3 shows a state in which these lip portions 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 strip portions 38 and 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 is the dust strip portions 38 and 40. Slide against.

Furthermore, the elastic ring 20 of the fixed seal member 10 has a dust lip 42. The dust lip portion 42 extends from the vicinity of the inner cylindrical portion 20b to the atmosphere A side, bends, and further extends obliquely outward in the radial direction and toward the atmosphere A side. The tip of the dust strip portion 42 contacts the rigid flange portion 18b of the flange 14 of the rotary seal member 8, and when the rotary seal member 8 rotates with the rotary shaft 4, the rigid flange portion 18b slides against the dust strip portion 42. Move.

The dust strips 38, 40, and 42 mainly play a role of preventing entry of foreign matters (mud, muddy water, and dust) from the atmosphere A side to the equipment internal space S side. However, the dust lip portions 38, 40, 42 may prevent the lubricant from flowing out from the device internal space S side to the atmosphere A side.

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

A plurality (five in this embodiment) of protrusions 46 are formed on the outer peripheral surface of the outer cylindrical portion 44. These protrusions 46 are arranged on the outer cylindrical portion 44 at intervals in a direction parallel to the axial direction of the shaft hole 6. These protrusions 46 protrude radially outward from the outer peripheral surface of the outer cylindrical portion 44, and each protrusion 46 has an annular shape that is continuous in the circumferential direction. As shown in FIG. 2, each protrusion 46 has a substantially semicircular outline when not elastically deformed. However, the outline of the protrusion 46 is not limited to the illustration, and has various outlines. Also good.

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

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

In order to reduce the entry of foreign matter from the atmosphere A side into the device internal space S, a protective cover may be provided on the atmosphere A side further than the sealing device 1. However, since this sealing device 1 has a high characteristic of preventing the entry of foreign matter, it is not necessary to provide such a protective cover.

The protrusion 46 is formed to form a plurality of ridges in a direction parallel to the axial direction of the shaft hole 6 (that is, in the cross section shown in FIGS. 1 and 2). In this embodiment, each protrusion 46 corresponds to a bump. In this embodiment, the plurality of ridges exhibits a waveform. The presence of a plurality of ridges in a direction parallel to the axial direction of the shaft hole 6 prevents foreign matter from entering from the atmosphere A side in a plurality of stages.

FIG. 4 is an enlarged cross-sectional view of a part of the rotary seal member 8 of the sealing device 1 of FIG. In FIG. 4, hatching is omitted. 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 includes a plurality of annular protrusions 46 (indicated by 46a to 46e in FIG. 4). ) Has a smaller diameter from the atmosphere A side toward the device internal space S side. That is, the protrusion 46a closest to the atmosphere A has the largest diameter Da even when it is in contact with the inner peripheral surface of the large-diameter cylindrical portion 22d of the outer cylindrical body 26 of the fixed seal member 10. The protrusion 46b that is second on the atmosphere A side has the second largest diameter Db. The third protrusion 46c on the atmosphere A side has the third largest diameter Dc. The protrusion 46d that is fourth on the atmosphere A side has the fourth largest diameter Dd. The protrusion 46e closest to the device internal space S has the smallest diameter De.

In this configuration, the projection 46a having the largest 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 seal member 10 with a strong force. When the projection 46a is worn, another projection 46b having the next largest 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. When the protrusion 46b is worn, another protrusion 46c having the next largest diameter Dc 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. When the projection 46c is worn, another projection 46d having the next largest diameter Dd on the device internal space S side is pressed with a strong force against the inner peripheral surface of the large-diameter cylindrical portion 22d. When the projection 46d is worn, another projection 46e having the next largest diameter De 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. Therefore, even if there is local wear, the sealing device 1 has a long life. In other words, it is possible to prevent foreign matter from entering for a long 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 protrusions 46 have a smaller diameter from the atmosphere A side toward the device internal space S side. In order to ensure this, in a state where the rotary seal member 8 is not combined with the fixed seal member 10 (FIG. 2), the outer cylindrical portion 44, particularly the outer peripheral surface thereof, It extends obliquely outward in the radial direction. In a state where the rotary seal member 8 and the fixed seal member 10 are combined (FIG. 1), the projection 46 having the largest diameter on the atmosphere A side is regulated by the large-diameter cylindrical portion 22d of the fixed seal member 10, and the outer cylindrical portion. 44, in particular, the inclination angle of the outer peripheral surface with respect to the axis of the shaft hole 6 is small. However, since the outer cylindrical portion 44 was originally slanted, the plurality of protrusions 46 remained from the atmosphere A side even after elastic deformation. Having a smaller diameter toward the S side is maintained.

As a modification, even when one protrusion is formed in a spiral shape, the raised portion that contacts the inner peripheral surface of the large-diameter cylindrical portion 22d can be changed with local wear. However, in this embodiment, a plurality of separate annular protrusions 46 are disposed on the outer cylindrical portion 44 of the rotary seal member 8 at intervals from each other in a direction parallel to the axial direction of the shaft hole 6. It is possible to easily provide a plurality of ridges in a direction parallel to the axial direction of the shaft hole 6 as compared with the case where one protrusion 46 is formed in a spiral shape.

As described above, in the sealing device 1, various measures are taken to prevent or reduce the entry of foreign matter from the atmosphere A side into the equipment internal space S. Therefore, the sealing device 1 is a mud or dusty environment such as a railcar bogie, a sintered pallet bogie, a construction machine, a truck trunnion suspension, and an agricultural machine (cultivator, tractor, rice transplanter, etc.). Even in the equipment used in the above, the sealing function is suitably exhibited. However, the application of the sealing device 1 is not limited to such a device, and may be another device.

Lubricant is disposed in the space 50 (see FIG. 1) between the seal lip portion 36 and the dust lip portion 38, the space 52 between the dust lip portions 38, 40, and the space 54 between the dust lip portions 40, 42. May be. In this case, the wear resistance of these lip portions is improved.

Other Modifications Although the embodiment of the present invention has been described above, the above description is not intended to limit the present invention, and various modifications including deletion, addition, and replacement of components are included in the technical scope of the present invention. Can be considered.
For example, the shape and number of the lip portions of the fixed seal member 10 are not limited to those described above.

Further, the number of the protrusions 46 is not limited to the embodiment.
In the said embodiment, the axis | shaft 4 is a rotating shaft and the housing which has the axial 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, the shaft 4 (and the seal member 8) may be stationary, the housing (and the seal member 10) may rotate around it, and the shaft 4 and the housing may also rotate.

A Atmosphere S Equipment internal space 1 Sealing device 4 Rotating shaft (inner member)
5 Housing (outside member)
6 Shaft hole (hole)
8 Rotating seal member (first seal member)
10 Fixed seal member (second seal member)
12 Sleeve 14 Flange 16 Elastic ring 16a Inner cylindrical part 16b Elastic flange part 18 Reinforcement ring 18a Outer cylindrical part 18b Rigid flange part 20 Elastic ring 20a Outer cylindrical part 20b Inner cylindrical part 22 Reinforcement ring 22a Cylindrical part 22b Bending part 22c Connection part 22d Large-diameter cylindrical portion 22e Connecting portion 26 Outer cylindrical body 30 Garter spring 32 Receiving groove 36 Seal lip portion 38, 40, 42 Dustrip portion 44 Outer cylindrical portion 46 Projection 50, 52, 54 Space

Claims (4)

A first seal member fixed to an inner member of the two members that rotate relative to each other;
A second seal member fixed to the inner surface of the hole of the outer member of the two members that rotate relative to each other, and the first seal member slidably contacted with the second seal member;
A sealing device that seals the lubricant in the internal space of the device to the internal space of the device,
The second seal member is
An outer cylindrical body fixed to the hole;
A lip portion slidably contacting the first seal member;
The first seal member is
A sleeve fixed to the inner member;
A flange that is integrally connected to the end of the sleeve on the atmosphere side and radially spreads outside the sleeve;
An outer cylindrical portion concentric with the hole is formed on an outer edge of the flange, and an outer peripheral surface of the outer cylindrical portion slides on an inner peripheral surface of the outer cylindrical body of the second seal member. An annular projection is formed, which is movable and has an annular protrusion that is in sealing contact with the inner circumferential surface of the outer cylindrical body over the entire circumference. The sealing device according to claim 1, wherein the protrusion is formed to form a plurality of ridges in a direction parallel to the axial direction of the hole. The outer cylindrical portion of the first seal member extends from the outer end edge of the flange toward the atmosphere side,
The sealing device according to claim 2, wherein the plurality of bulges have a diameter that decreases from the atmosphere side toward the device internal space side. The plurality of separate annular protrusions are disposed on the outer cylindrical portion of the first seal member and spaced from each other in a direction parallel to the axial direction of the hole. Or the sealing device of 3.

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