JP6986922B2 - Sealing device - Google Patents

Description

The present invention relates to a sealing device that seals the inside of a rolling bearing.

Patent Document 1 discloses a sealing device that seals the inside of a rolling bearing suitable for use in a railway vehicle. The sealing device comprises an internal ring supported by a rotary mechanical element and an external ring comprising an elastomeric sealing body supported by a housing to be sealed. A plurality of lips extending toward the inner ring are formed on the seal body.

Japanese Unexamined Patent Publication No. 2015-224788

Rolling bearings of railroad vehicles or large vehicles such as trucks and buses are subject to heavy loads, large amounts of dust, and are subject to significant temperature changes. Especially around railway vehicles, there is a lot of iron powder generated by the wear of railways. As the rolling bearings are repaired, the sealing device needs to be replaced.

Therefore, the present invention provides a sealing device that can be easily removed.

The sealing device according to an aspect of the present invention is a sealing device that is arranged between a relatively rotating inner member and an outer member of a rolling bearing and seals a gap between the inner member and the outer member. It includes an annular inner seal member fixed to the inner member and an annular outer seal member fixed to the inner surface of the hole of the outer member and slidably contacting the inner seal member. The inner sealing member has a sleeve fixed to the inner member and a flange integrally connected to the end of the sleeve on the atmosphere side and extending radially to the outside of the sleeve. The outer seal member includes a rigid portion formed of a rigid material and an elastic portion formed of an elastic material fixed to the rigid portion. A seal lip that slidably contacts the sleeve of the inner sealing member is formed in the elastic portion, and a dust strip that slidably contacts the flange of the inner sealing member is formed in the elastic portion. Has been done. The rigid portion includes a cylindrical portion fitted into the inner surface of the hole of the outer member, an annular portion integrally connected to the end portion of the cylindrical portion on the atmosphere side and extending inward in the radial direction of the cylindrical portion. It is provided with a plurality of axially projecting portions protruding from the annular portion toward the atmosphere side in the axial direction of the outer sealing member.

In this embodiment, a plurality of axially projecting portions are provided on the rigid portion of the outer seal member so as to project in the axial direction. The rigid portion is provided with a cylindrical portion that is fitted into the inner surface of the hole of the outer member of the rolling bearing, and a plurality of axially protruding portions are used to apply a force inward in the radial direction to the outer seal member. Further, by compressing the elastic portion and thus the rigid portion of the outer seal member in the radial direction, the cylindrical portion of the rigid portion of the outer seal member can be partially separated from the inner surface of the hole of the outer member. After that, the outer seal member can be moved in the axial direction to pull out the outer seal member from the hole of the outer member of the rolling bearing. Once the cylindrical portion of the rigid portion of the outer seal member is partially separated from the inner surface of the hole of the outer member, the outer seal member is pulled out from the hole of the outer member of the rolling bearing by utilizing the elastic deformation of the outer seal member. Is easy. Therefore, the sealing device can be easily removed.

Preferably, the plurality of axially projecting portions have a shape in which a plurality of portions of the annular portion separated at angular intervals in the circumferential direction are bent, and the plurality of axial lines of the annular portion. The plurality of portions where the directional protrusions are not formed are continuous with the plurality of inner extension portions extending radially inward from the annular portion, and the axially protruding portions and the inner extension portions include the plurality of portions. The elastic portion is fixed.

In this case, not only a plurality of axially projecting portions partial rigidity portion is provided, a plurality of inner extension portions apart at angular intervals in the circumferential direction is provided in the rigid portion, the axial protrusion And the inner extension reinforces the elastic part. Therefore, the strength of the elastic portion provided with the seal lip and the dust strip is increased.

Preferably, the elastic portion comprises a cylindrical tubular wall portion extending toward the flange of the inner sealing member, and the plurality of axially projecting portions are embedded in the tubular wall portion. A gap is provided between the flange and the flange.

In this case, even if foreign matter from the outside tries to enter the sealing device, many foreign matter is repelled by the cylinder wall portion of the outer sealing member or the flange of the inner sealing member. Foreign matter that has passed through the gap between the cylinder wall portion and the flange reaches the dust strip, and by setting this gap small, the amount of foreign matter that reaches the dust strip can be reduced. Since the tubular wall portion is reinforced by a plurality of axially projecting portions embedded therein, it can withstand the force even if the force received from the foreign matter is strong.

Preferably, the elastic portion of the outer sealing member comprises an annular base disposed radially inward of the plurality of axially protruding portions and supported by the rigid portion, the dust strip from the base to the atmosphere. It has a proximal end portion extending laterally and radially inward, and a distal end portion extending laterally and radially outwardly from the proximal end portion, and the distal end portion is slidable on the flange of the inner sealing member. Contact.

In this case, the dust strip comprises a proximal end portion extending radially inward and a tip portion extending radially outward, the tip portion slidably contacting the flange of the inner sealing member. Therefore, even if the shaft inserted into the rolling bearing or the inner member of the rolling bearing is eccentric or has a low roundness, the dust strip will contact the flange with almost uniform force over the entire circumference. .. In this way, the sealing performance of the dust strip is ensured over the entire circumference. Further, since the tip portion of the dust strip exerts a force on the flange in the axial direction instead of the radial direction, it is possible to suppress an increase in torque applied to the shaft.

Preferably, the seal lip comprises a proximal end portion extending from the base portion to the atmosphere side and radially inward, and a tip portion extending from the proximal end portion to the bearing internal side and radially inward, said to be the seal. The tip portion of the lip slidably contacts the outer peripheral surface of the sleeve of the inner sealing member.

In this case, the seal lip has a bent shape with a base end portion extending toward the atmosphere and a tip portion extending toward the inner side of the bearing, and the tip portion is on the outer peripheral surface of the sleeve of the inner sealing member. Sliding contact. Since the seal lip has a bent shape, the seal lip is easily deformed. Therefore, even if the shaft inserted into the rolling bearing or the inner member of the rolling bearing is eccentric or has a low roundness, the seal lip contacts the flange with almost equal force over the entire circumference. .. In this way, the sealing performance of the seal lip is ensured over the entire circumference.

It is sectional drawing of the sealing apparatus which concerns on embodiment of this invention. It is a perspective view which shows the rigid body part of the sealing device of FIG. It is sectional drawing of the sealing device which removed the inner sealing member from a rolling bearing. It is sectional drawing of the outer seal member of the sealing device removed from a rolling bearing.

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

FIG. 1 shows an axle bearing of a railroad vehicle, which is an example of a rolling bearing 2 in which the sealing device 1 according to the embodiment of the present invention is used. However, the application of the present invention is not limited to bearings for railway vehicles, and the present invention can also be applied to bearings for axles of large automobiles such as trucks and buses. Further, the rolling bearing 2 shown in the figure is an RCT (Rotating End Cap Tapered Roller) bearing, but the application of the present invention is not limited to the RCT bearing and has an RCC (Rotating End Cap) having another type of rolling element. Cylindrical Roller) The present invention is also applicable to other rolling bearings such as bearings, ball bearings and needle bearings.

As shown in FIG. 1, the rolling bearing 2 includes an inner ring (inner member) 6 into which the axle 4 is inserted, an outer ring (outer member) 8 arranged outside the inner ring 6, and an inner ring 6 and an outer ring 8. It has a plurality of rollers 10 arranged in a row between them, and a cage 14 for holding the rollers 10 in a fixed position. While the outer ring 8 is fixed, the inner ring 6 rotates with the rotation of the axle 4. The cage 14 is fixed to the outer ring 8.

The sealing device 1 is arranged between the inner ring 6 and the outer ring 8 that rotate relatively, and seals the gap between the inner ring 6 and the outer ring 8. By the action of the sealing device 1, the outflow of grease, that is, the lubricant from the inside of the rolling bearing 2 is prevented or reduced, and foreign matter (including water (including muddy water or salt water)) and / or foreign matter (including muddy water or salt water) into the inside of the rolling bearing 2 from the outside. Or the inflow of dust (including iron powder) is prevented or reduced. In FIG. 1, the arrow D shows an example of the direction of the flow of foreign matter from the outside.

Although only the left side portion with respect to the axle 4 is shown in FIG. 1, the sealing device 1 and the rolling bearing 2 have a rotationally symmetric shape. The upper side of FIG. 1 is the bearing internal side B, and the lower side is the atmospheric side A. However, a sealing device similar to the sealing device 1 is provided on the opposite side of the sealing device 1 with the rolling bearing 2 interposed therebetween.

The sealing device 1 includes an annular inner sealing member 20 and an annular outer sealing member 30. The inner seal member 20 is fixed to the inner ring 6. The outer seal member 30 is fixed to the inner surface of the hole 8A of the outer ring 8, and the inner seal member 20 is slidably contacted with the outer seal member 30.

The inner seal member 20 is made of a rigid material, for example metal. The inner seal member 20 includes a sleeve 22 and a flange 24. The sleeve 22 is fixed to the inner ring 6. The fixing method may be, for example, a tight fit. The flange 24 is integrally connected to the end of the sleeve 22 on the atmosphere side and extends radially to the outside of the sleeve 22.

The outer sealing member 30 has a double structure including a rigid portion 32 formed of a rigid material such as metal and an elastic portion 34 formed of an elastic material such as an elastomer. The rigid portion 32 reinforces the elastic portion 34.

The rigid portion 32 has a cylindrical portion 36 fixed to the inner surface of the hole 8A of the outer ring 8, an annular portion 38, a plurality of axially projecting portions 40, and a plurality of inner extension portions 42.

The cylindrical portion 36 is fitted into the inner surface of the hole 8A of the outer ring 8 by tightening. The end portion 36a of the bearing inner side B of the cylindrical portion 36 is formed as a hook extending radially outward. A peripheral groove, that is, a recess 8B is formed in the hole 8A, and the end portion 36a of the cylindrical portion 36 is fitted into the recess 8B.

The annular portion 38 is integrally connected to the end of the cylindrical portion 36 on the atmospheric side A and extends radially inward of the cylindrical portion 36. The annular portion 38 extends in a plane perpendicular to the axial direction of the outer seal member 30.

The plurality of axially projecting portions 40 project from the annular portion 38 toward the atmosphere side A in the axial direction of the outer seal member 30. As shown in FIG. 2, the plurality of axially projecting portions 40 have a shape in which a plurality of portions of the annular portion 38 separated at angular intervals in the circumferential direction are bent. Further, the plurality of portions of the annular portion 38 in which the plurality of axially projecting portions 40 are not formed are continuous with the plurality of inner extension portions 42 extending inward in the radial direction from the annular portion 38. Preferably, the axially projecting portions 40 are arranged at equal intervals, and the inner extension portions 42 are also arranged at equal intervals, but these angular intervals may not be equal. In this embodiment, eight axial protrusions 40 and eight inner extension portions 42 are provided, but the number of axial protrusions 40 and the number of inner extension portions 42 are not limited to two or more. It's okay.

Returning to FIG. 1, the elastic portion 34 has an annular base portion 50 supported by the rigid portion 32, a seal lip 52, a dust strip 54, a radial protrusion 56, and a tubular wall portion 60.

The base portion 50 of the elastic portion 34 is an annular portion arranged radially inside the plurality of axially protruding portions 40 of the rigid portion 32, and is fixed to the plurality of inner extension portions 42 of the rigid portion 32. The entire plurality of inner extension portions 42 intermittently arranged in the circumferential direction are embedded in the annular base 50 that is continuous in the circumferential direction, and the inner extension portion 42 reinforces the base 50.

The seal lip 52 is a plate-shaped ring that extends from the base 50 and slidably contacts the outer peripheral surface of the sleeve 22 of the inner seal member 20. The seal lip 52 mainly has a function of preventing or reducing grease leakage from the bearing inner side B to the atmospheric side A. The seal lip 52 has a base end portion 52a extending from the base portion 50 to the atmosphere side A and radially inward, and a tip portion 52b extending from the base end portion 52a to the bearing inner side B and radially inward. The tip portion 52b is slidably in contact with the outer peripheral surface of the sleeve 22 of the inner sealing member 20 over the entire circumference. The thickness of the base end portion 52a is larger than the thickness of the tip end portion 52b.

The dust strip 54 is a plate-shaped ring extending from the base 50 and slidably contacting the side surface of the flange 24 of the inner sealing member 20 on the bearing inner side B side. The dust strip 54 mainly has a function of preventing or reducing the intrusion of foreign matter from the atmospheric side A to the bearing internal side B. The dust strip 54 has a base end portion 54a extending from the base portion 50 to the atmosphere side A and radially inward, and a tip portion 54b extending from the base end portion 54a to the atmosphere side A and radially outward. , The tip portion 54b slidably contacts the side surface of the flange 24 of the inner seal member 20 on the bearing inner side B side over the entire circumference. The thickness of the base end portion 54a is larger than the thickness of the tip end portion 54b.

The radial protrusion 56 projects inward in the radial direction from the inner edge of the base 50. The radial projection 56 has a trapezoidal cross section that is wide on the radial outside and narrow on the inside. The radial protrusion 56 does not come into contact with the inner sealing member 20, and a small annular gap 58 is provided between the radial protrusion 56 and the sleeve 22 of the inner sealing member 20. The gap 58 assists the sealing performance of the seal lip 52 by obstructing the flow of grease from the bearing internal side B to the atmospheric side A and reducing the amount of grease reaching the seal lip 52.

The tubular wall portion 60 is a cylindrical portion extending from the outer edge of the base portion 50 toward the flange 24 of the inner sealing member 20, and is fixed to a plurality of axially projecting portions 40 of the rigid portion 32. In the cylindrical cylindrical wall portion 60 that is continuous in the circumferential direction, the entire plurality of axially projecting portions 40 that are intermittently arranged in the circumferential direction are embedded, and the axially projecting portion 40 has the tubular wall portion 60. Reinforce.

In the elastic portion 34, not only the inner extension portion 42 of the rigid portion 32 but also a part of the annular portion 38 and the entire plurality of axially projecting portions 40 are embedded. Specifically, a part of the surface of the atmospheric side A of the annular portion 38 is covered with a part 62 of the elastic portion 34, and a part of the surface of the bearing inner side B of the annular portion 38 is a part of the elastic portion 34. The portion is covered with 64, and the axially protruding portion 40 is covered with the tubular wall portion 60 of the elastic portion 34. However, the annular portion 38 does not have to be covered with the elastic material.

A plurality of axially projecting portions 40 and a tubular wall portion 60 of the elastic portion 34 intermittently provided in the rigid portion 32 of the outer seal member 30 extend toward the flange 24 of the inner seal member 20. The cylinder wall portion 60 does not come into contact with the flange 24, and a gap 68 is provided between the cylinder wall portion 60 and the flange 24.

With the repair of the rolling bearing 2, it is necessary to replace the sealing device 1. The work of removing the sealing device 1 will be described with reference to FIGS. 3 and 4.

First, as shown in FIG. 3, the inner seal member 20 fixed to the inner ring 6 by tightening is pulled out from the inner ring 6. This work may be performed by the operator or by using a jig (not shown).

Next, as shown in FIG. 4, the elastic portion 34 and the rigid portion 32 of the outer seal member 30 are subjected to a force F inward in the radial direction to the outer seal member 30 by the operator's hand or a jig. By compressing in the radial direction, the cylindrical portion 36 of the rigid portion 32 of the outer sealing member 30 is partially separated from the inner surface of the hole 8A of the outer ring 8.

Further, by pulling the outer seal member 30 with the force S by the operator's hand or a jig, the outer seal member 30 is moved in the axial direction, and the outer seal member 30 is moved from the hole 8A of the outer ring 8 of the rolling bearing 2. Can be extracted. In this way, the sealing device 1 can be easily removed.

In this embodiment, the rigid portion 32 is provided with a cylindrical portion 36 that is fitted into the inner surface of the hole 8A of the outer ring 8 of the rolling bearing 2, and the end portion 36a of the cylindrical portion 36 is formed in the recess 8B of the hole 8A. It is fitted. However, the elastic portion 34 and the rigid portion 32 of the outer seal member 30 are compressed in the radial direction by applying a force F inward in the radial direction to the outer seal member 30 by using the plurality of axially projecting portions 40. As a result, the cylindrical portion 36 of the rigid portion 32 of the outer sealing member 30 can be partially separated from the inner surface of the hole 8A of the outer ring 8. After that, the outer seal member 30 can be moved in the axial direction, and the outer seal member 30 can be pulled out from the hole 8A of the outer ring 8 of the rolling bearing 2. Once the cylindrical portion 36 of the rigid portion 32 of the outer seal member 30 is partially separated from the inner surface of the hole 8A of the outer ring 8, the outer seal member 30 is rolled on the outer seal member 2 by utilizing the elastic deformation of the outer seal member 30. It is easy to pull out from the hole 8A of the outer ring 8. Therefore, the sealing device 1 can be easily removed.

In this embodiment, the plurality of axially projecting portions 40 have a shape in which a plurality of portions of the annular portion 38 of the rigid portion 32 that are separated from each other at angular intervals in the circumferential direction are bent, and the annular portion 38 has a shape. Of these, the plurality of points where the plurality of axially projecting portions 40 are not formed are continuous with the plurality of inner extension portions 42 extending inward in the radial direction from the annular portion 38. Thus, not only the rigid portion 32 a plurality of axial protrusions component 40 is provided, a plurality of inner extension portion 42 away at the corner intervals in the circumferential direction are provided in the rigid portion 32. These axially protruding portions 40 and the inner extension portions 42 reinforce the elastic portions 34. Therefore, the strength of the elastic portion 34 provided with the seal lip 52 and the dust strip 54 is increased.

In this embodiment, the elastic portion 34 includes a cylindrical tubular wall portion 60 extending toward the flange 24 of the inner sealing member 20, and a plurality of axially projecting portions 40 are embedded in the tubular wall portion 60. A gap 68 is provided between the wall portion 60 and the flange 24. Even if foreign matter from the outside tries to enter the sealing device 1, many foreign matter is repelled by the cylinder wall portion 60 of the outer sealing member 30 or the flange 24 of the inner sealing member 20. Foreign matter that has passed through the gap 68 between the cylinder wall portion 60 and the flange 24 reaches the dust strip 54, but by setting the gap 68 small, the amount of foreign matter that reaches the dust strip 54 can be reduced. .. Since the cylinder wall portion 60 is reinforced by a plurality of axially projecting portions 40 embedded therein, it can withstand the force even if the force received from the foreign matter is strong.

In this embodiment, the dust strip 54 comprises a proximal end portion 54a extending radially inward and a tip portion 54b extending radially outward, with the tip portion 54b sliding onto the flange 24 of the inner seal member 20. Contact as much as possible. Therefore, even if the axle 4 inserted into the rolling bearing 2 or the inner ring 6 of the rolling bearing 2 is eccentric or has a low roundness, the dust strip 54 is substantially uniform over the entire circumference with respect to the flange 24. Contact with force. In this way, the sealing performance of the dust strip 54 is ensured over the entire circumference. Further, since the tip portion 54b of the dust strip 54 exerts a force on the flange 24 not in the radial direction but in the axial direction, it is possible to suppress an increase in torque applied to the shaft.

In this embodiment, the seal lip 52 has a bent shape including a base end portion 52a extending toward the atmosphere side A and a tip portion 52b extending toward the bearing inner side B, and the tip portion 52b is an inner seal member. Slidably contacts the outer peripheral surface of the sleeve 22 of 20. Since the seal lip 52 has a bent shape, the seal lip 52 is easily deformed. Therefore, even if the axle 4 inserted into the rolling bearing 2 or the inner ring 6 of the rolling bearing 2 is eccentric or has a low roundness, the seal lip 52 is substantially uniform over the entire circumference with respect to the flange 24. Contact with force. In this way, the sealing performance of the seal lip 52 is ensured over the entire circumference.

Other Modifications Although the embodiments of the present invention have been described above, the above description does not limit the present invention, and various modifications including deletion, addition, and replacement of components are included in the technical scope of the present invention. An example is possible.

For example, the shape and number of lips of the sealing device are not limited to those described above.

In the above embodiment, the inner ring 6 which is an inner member is a rotating member, and the outer ring 8 which is an outer member is a stationary member. However, the present invention is not limited to the above embodiment, and can be applied to sealing a plurality of members that rotate relative to each other. For example, the inner member may be stationary and the outer member may rotate, or all of these members may rotate.

1 Sealing device 2 Rolling bearing 4 Axle 6 Inner ring (inner member)
8 Outer ring (outer member)
8A Hole 10 Roller 20 Inner seal member 30 Outer seal member 22 Sleeve 24 Flange 32 Rigid part 34 Elastic part 36 Cylindrical part 38 Circular part 40 Axial protruding part 42 Inner extension part 50 Base part 52 Seal lip 52a Base end part 52b Tip part 54 Dustrip 54a Base end 54b Tip 60 Cylinder wall 68 Gap

Claims (5)

A sealing device that is arranged between a relatively rotating inner member and an outer member of a rolling bearing and seals a gap between the inner member and the outer member.
An annular inner seal member fixed to the inner member and
It is provided with an annular outer seal member that is fixed to the inner surface of the hole of the outer member and is slidably contacted with the inner seal member.
The inner seal member is
The sleeve fixed to the inner member and
It has a flange that is integrally connected to the end of the sleeve on the atmosphere side and extends radially to the outside of the sleeve.
The inner seal member can be pulled out from the inner member toward the atmosphere.
The outer seal member is
Rigid parts formed from rigid materials and
It is provided with an elastic portion formed of an elastic material fixed to the rigid portion, and has an elastic portion.
A seal lip that slidably contacts the sleeve of the inner sealing member is formed on the elastic portion.
A dust strip that slidably contacts the flange of the inner sealing member is formed on the elastic portion.
The rigid part is
A cylindrical portion fitted into the inner surface of the hole of the outer member and
An annular portion that is integrally connected to the end of the cylindrical portion on the atmosphere side and extends inward in the radial direction of the cylindrical portion.
Wherein is disposed radially inward away from the cylindrical portion, toward the atmosphere side from the annular portion protrudes in the axial direction of the outer seal member, a plurality of axes spaced from each other at angular intervals in the circumferential direction With a directional protrusion ,
The outer seal member can be pulled out from the hole of the outer member toward the atmosphere.
A sealing device characterized by that. The plurality of axially projecting portions have a shape in which a plurality of portions of the annular portion separated at angular intervals in the circumferential direction are bent.
The plurality of portions of the annular portion in which the plurality of axially projecting portions are not formed are continuous with the plurality of inner extension portions extending radially inward from the annular portion.
The sealing device according to claim 1, wherein the elastic portion is fixed to the axially protruding portion and the inner extension portion. The elastic portion includes a cylindrical tubular wall portion extending toward the flange of the inner sealing member, and the plurality of axially projecting portions are embedded in the tubular wall portion, and the tubular wall portion and the flange. The sealing device according to claim 1 or 2, wherein a gap is provided between the two. The elastic portion of the outer sealing member comprises an annular base disposed radially inside the plurality of axially protruding portions and supported by the rigid portion.
The dust strip comprises a proximal end portion extending from the base portion to the atmosphere side and radially inward, and a tip portion extending from the proximal end portion to the atmosphere side and radially outward.
The sealing device according to any one of claims 1 to 3, wherein the tip portion slidably contacts the flange of the inner sealing member. The seal lip includes a proximal end portion extending from the base portion to the atmosphere side and radially inward, and a tip portion extending from the proximal end portion to the bearing internal side and radially inward.
The sealing device according to claim 4, wherein the tip portion of the seal lip is slidably in contact with the outer peripheral surface of the sleeve of the inner sealing member.

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