JP2019019927A - Sealing device - Google Patents

Abstract

To provide a sealing device which is high in stability when laminated in a plurality of pieces.SOLUTION: A sealing device is arranged between an inside member and an outside member of a rolling bearing which relatively rotate, and seals a clearance between the inside member and the outside member. The sealing member comprises: a cylindrical part into which a cylindrical end part of the outside member is fit; an annular wall part extending to the inside from the cylindrical part in a radial direction; an inside annular part extending to the inside of the annular wall part in the radial direction; at least one lip extending toward the inside member from the inside annular part; and an auxiliary lip which is arranged outside in the radial direction rather than the cylindrical part, extends to a direction opposite to the cylindrical part, and extends toward a flange which is hung out to the outside in the radial direction rather than the outside member out of the inside member of the rolling bearing. The cylindrical part has a base end face continuous to the annular wall part, and a tip face located at a side opposite to the annular wall part. The base end face and the tip face intersect with a center axial line of the cylindrical part, and are parallel with each other. The inside annular part does not protrude from the tip face of the cylindrical part in a direction parallel with the center axial line.SELECTED DRAWING: Figure 4

Description

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

  Rolling bearings, such as ball bearings, are well known and are used, for example, in automobile hubs. As a sealing device for sealing the inside of a rolling bearing, there is one described in Patent Document 1. The sealing device includes an annular body fixed to the outer ring of the rolling bearing, a radial lip extending radially inward from the annular body, and two side lips extending laterally from the annular body. The radial lip is in contact with the outer peripheral surface of the inner ring of the bearing or the outer peripheral surface of a part fixed to the inner ring, and has a function of sealing the lubricant inside the bearing, and the two side lips are in contact with the flange of the inner ring. Thus, it has a function of sealing so that foreign matters such as water and dust do not enter the inside of the bearing from the outside.

Japanese Patent No. 3991200

  In a manufacturing process, a conveyance process, or an installation process, when a large number of sealing devices are stacked, it is desirable that stability be high.

  Therefore, the present invention provides a sealing device that can be stably stacked.

  A sealing device according to an aspect of the present invention is a sealing device that is disposed 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. A cylindrical shape having an inner peripheral surface having a central axis, the cylindrical end portion of the outer member of the rolling bearing being fitted into the inner peripheral surface, and contacting the outer peripheral surface of the end portion An annular wall portion that extends radially inward from the cylindrical portion, is opposed to an end surface of the end portion of the outer member, extends radially inward of the annular wall portion, and the outer member An inner annular portion disposed radially inward of the end portion, at least one lip extending from the inner annular portion toward the inner member of the rolling bearing, and radially outward of the cylindrical portion. Arranged and extends in a direction opposite to the cylindrical portion. An auxiliary lip extending toward a flange projecting radially outward from the outer member of the inner member of the rolling bearing, and the cylindrical portion includes a base end surface connected to the annular wall portion, and A distal end surface on the opposite side of the annular wall portion, wherein the proximal end surface and the distal end surface are orthogonal to the central axis and parallel to each other, and the inner annular portion is parallel to the central axis. In any direction does not protrude from the tip surface of the cylindrical portion.

  In this aspect, the cylindrical part of the sealing device has a base end face and a tip end face that are parallel to each other. Accordingly, it is possible to stably stack a large number of sealing devices by placing the distal end surface of the cylindrical portion of the sealing device on the proximal end surface of the cylindrical portion of another sealing device of the same type. In said aspect, the cylindrical edge part of the outer member of a rolling bearing is inserted in the cylindrical part of a sealing device. For this reason, the cylindrical part of the sealing device can be formed to have a certain size, which contributes to the stable stacking of the sealing device. Further, the inner annular portion interposed between the cylindrical portion and the lip does not protrude outward from the tip surface of the cylindrical portion in a direction parallel to the axis of the rolling bearing. Therefore, when a plurality of sealing devices are stacked, the inner annular portion does not come into contact with other sealing devices, and stability when the sealing devices are stacked can be improved. Further, the auxiliary lip can repel foreign substances such as water (including muddy water or salt water) and dust coming from the outside.

  Preferably, the sealing device includes an elastic ring formed of an elastic body and a reinforcing ring formed of a rigid body that reinforces the elastic ring, and the cylindrical portion is concentric formed of the reinforcing ring. The two cylinders overlap in the radial direction. In this case, since the cylindrical portion has two concentric radial cylinders formed of reinforcing rings, a large width of the cylindrical portion can be ensured. For this reason, it is possible to provide the front end surface of a large area in a cylindrical part, and can further improve the stability of the stacked sealing device.

  Preferably, the annular wall portion has an outer surface on the side opposite to the end portion of the outer member, and a convex portion protruding from the base end surface of the cylindrical portion is formed on the outer surface. Has been. In this case, since the convex part which protrudes rather than a base end surface is provided in the inner side of the base end surface on which the tip end face of other sealing devices is mounted, the movement of the stacked sealing devices in the radial direction ( That is, horizontal movement) is suppressed. Therefore, the stability of the stacked sealing devices can be further enhanced.

  The diameter of the portion where the auxiliary lip and the base end surface of the tubular portion intersect is equal to or greater than the outer diameter of the distal end surface of the tubular portion, and the difference between the diameter and the outer diameter is less than 1.5 mm. Good. In this case, the distal end surface of the cylindrical portion of the sealing device can be brought into contact with the proximal end surface inside the auxiliary lip of another sealing device of the same type, and the stability of the stacked sealing devices is further enhanced. be able to.

It is a fragmentary sectional view of an example of the rolling bearing in which the sealing device concerning a plurality of embodiments of the present invention is used. It is a fragmentary sectional view at the time of use of the sealing device concerning a 1st embodiment of the present invention. It is sectional drawing at the time of non-use of the sealing device which concerns on 1st Embodiment. It is a fragmentary sectional view at the time of stacking of the sealing device concerning a 1st embodiment. It is a fragmentary sectional view at the time of use of the sealing device concerning a comparative example. It is a fragmentary sectional view at the time of stacking of the sealing device concerning a 2nd embodiment of the present invention. It is a fragmentary sectional view at the time of stacking of the sealing device concerning a 3rd embodiment of the present invention.

Hereinafter, a plurality of embodiments according to the present invention will be described with reference to the accompanying drawings.
1st Embodiment FIG. 1: shows the hub bearing for motor vehicles which is an example of the rolling bearing in which the sealing device which concerns on embodiment of this invention is used. However, the application of the present invention is not limited to the hub bearing, and the present invention can also be applied to other rolling bearings. In the following description, the hub bearing is a ball bearing. However, the application of the present invention is not limited to the ball bearing, and other rolling bearings such as roller bearings and needle bearings having other types of rolling elements. In addition, the present invention is applicable. The present invention is also applicable to rolling bearings used in machines other than automobiles.

  The hub bearing 1 is disposed outside a hub (inner member) 4 having a hole 2 into which a spindle (not shown) is inserted, an inner ring (inner member) 6 attached to the hub 4, and an outer side thereof. An outer ring (outer member) 8, a plurality of balls 10 arranged in a row between the hub 4 and the outer ring 8, a plurality of balls 12 arranged in a row between the inner ring 6 and the outer ring 8, and And a plurality of cages 14 and 15 for holding the balls in place.

  While the outer ring 8 is fixed, the hub 4 and the inner ring 6 rotate as the spindle rotates.

  A common central axis Ax of the spindle and the hub bearing 1 extends in the vertical direction of FIG. In FIG. 1, only the left portion with respect to the central axis Ax is shown. Although not shown in detail, the upper side of FIG. 1 is the outer side (outboard side) where the wheels of the automobile are arranged, and the lower side is the inner side (inboard side) where the differential gears are arranged. The outer side and the inner side shown in FIG. 1 mean the outer side and the inner side in the radial direction, respectively.

  The outer ring 8 of the hub bearing 1 is fixed to the hub knuckle 16. The hub 4 has an outboard side flange 18 projecting outward in the radial direction from the outer ring 8. A wheel can be attached to the outboard flange 18 by a hub bolt 19.

  A sealing device 20 that seals the gap between the outer ring 8 and the hub 4 is disposed near the end of the outer ring 8 on the outboard side, and inside the end of the outer ring 8 on the inboard side. A sealing device 21 that seals the gap between the outer ring 8 and the inner ring 6 is disposed. The action of the sealing devices 20 and 22 prevents the grease, that is, the lubricant from flowing out from the inside of the hub bearing 1 and prevents foreign matter (water (including muddy water or salt water) from entering the inside of the hub bearing 1 from the outside. And dust) are prevented. In FIG. 1, an arrow F indicates an example of the direction of foreign matter flow from the outside.

  The sealing device 20 is disposed between the rotating hub 4 of the hub bearing 1 and the fixed outer ring 8. The gap between the hub 4 and the outer ring 8 is sealed. As shown in FIG. 2, a part of the sealing device 20 includes a cylindrical end portion 8 </ b> A on the outboard side of the outer ring 8 of the hub bearing 1, and an outer peripheral surface 4 </ b> A near the ball 10 of the hub 4 of the hub bearing 1. The hub 4 is disposed in a space surrounded by a flange surface 4B that extends outward from the outer peripheral surface 4A of the hub 4 and an arcuate surface 4C that connects the outer peripheral surface 4A and the flange surface 4B. The flange surface 4B is a surface on the inboard side of the outboard side flange 18. Although the sealing device 20 has an annular shape, only the left side portion is shown in FIG.

  The sealing device 20 includes an elastic ring 22 formed of an elastic body, for example, an elastomer, and a rigid body that reinforces the elastic ring 22, for example, a single reinforcing ring 24 made of metal. A part of the reinforcing ring 24 is embedded in the elastic ring 22, and is in close contact with the elastic ring 22.

  The sealing device 20 includes a cylindrical portion 26, an outer edge portion 27, an annular wall portion 28, an inner annular portion 30, a radial lip 32, two side lips 34 and 36, and an auxiliary lip 37.

  The cylindrical portion 26 is a cylindrical portion centered on the central axis Ax (see FIGS. 1 and 3), and the cylindrical end portion 8A of the outer ring 8 is fitted into the inner peripheral surface thereof. The cylindrical portion 26 is fixed to the end portion 8A. The fixing method is not limited, but may be an interference fit, for example. That is, the end portion 8A may be press-fitted into the cylindrical portion 26.

  The cylindrical portion 26 includes an elastic ring 22 and a reinforcing ring 24, and includes two concentric cylinders 24 </ b> A and 24 </ b> B formed by the reinforcing ring 24. These cylinders 24 </ b> A and 24 </ b> B overlap in the radial direction, and their end portions are connected by a connecting portion 24 </ b> C that is a part of the reinforcing ring 24. The small-diameter cylinder 24B has the inner peripheral surface of the cylindrical portion 26, and comes into contact with the outer peripheral surface of the end portion 8A in an interference fit. Further, the elastic ring 22 constituting the cylindrical portion 26 has a thick portion 22A around the connection portion 24C of the reinforcing ring 24. The thick portion 22A has an inner diameter smaller than the inner diameter of the cylinder 24B, constitutes the inner peripheral surface of the cylindrical portion 26, and comes into contact with the outer peripheral surface of the end portion 8A of the outer ring 8 in an interference fit state.

  The outer edge portion 27 extends outward in the radial direction from the tubular portion 26 and is orthogonal to the central axis Ax of the hub bearing 1. The outer edge portion 27 is also composed of an elastic ring 22 and a reinforcing ring 24.

  The annular wall portion 28 extends radially inward from the tubular portion 26 and is orthogonal to the central axis Ax of the hub bearing 1. The annular wall portion 28 is also composed of the elastic ring 22 and the reinforcing ring 24, and a portion corresponding to the reinforcing ring 24 is opposed to the end surface of the end portion 8 </ b> A of the outer ring 8 and is in contact with the end surface.

  The inner annular portion 30 extends inward in the radial direction of the annular wall portion 28 and is disposed radially inward from the end portion 8A of the outer ring 8. In this embodiment, the inner annular portion 30 extends obliquely from the annular wall portion 28 radially inward and toward the inboard side, and further toward the radially inner side so as to be orthogonal to the central axis Ax of the hub bearing 1. It extends. The inner annular portion 30 is also composed of an elastic ring 22 and a reinforcing ring 24.

  The radial lip 32 and the side lips 34, 36 are formed only from an elastic body, and are thin plate-like rings extending from a portion corresponding to the elastic ring 22 of the inner annular portion 30, and their respective tips are attached to the hub 4. Contact. While the sealing device 20 is attached to the fixed outer ring 8, the hub 4 rotates, so that the lips 32, 34, 36 slide relative to the hub 4.

  The radial lip 32 extends from the innermost edge of the inner annular portion 30 and contacts the outer peripheral surface 4 </ b> A in the vicinity of the ball 10 of the hub 4. The radial lip 32 extends radially inward and toward the inboard side, and plays a role of mainly preventing the lubricant from flowing out from the inside of the hub bearing 1.

  The side lips 34 and 36 extend from the portion corresponding to the elastic ring 22 of the inner annular portion 30 to the side (outboard side) and radially outward. The side lip 34 contacts the flange surface 4B of the hub 4, and the side lip 36 contacts the flange surface 4B or the arc surface 4C. The side lips 34 and 36 mainly play a role of preventing foreign substances from flowing into the hub bearing 1 from the outside. The side lip 36 has a backup function that prevents foreign matter that has flowed through the side lip 34. Since the side lip 36 exists between the radial lip 32 and the side lip 34, it can also be called an intermediate lip.

  In FIG. 3, the radial lip 32 and the side lips 34 and 36 when the sealing device 20 is not disposed on the hub bearing 1 are shown. At this time, the radial lip 32 and the side lips 34, 36 are not subjected to external force and are in a straight state. However, as shown in FIG. 2, when the sealing device 20 is disposed on the hub bearing 1, these lips contact the hub 4 and are deformed by receiving a reaction force.

  The auxiliary lip 37 is formed only of an elastic body, is disposed radially outward from the tubular portion 26, and extends in the direction opposite to the tubular portion 26 (outboard side). The auxiliary lip 37 extends toward the recess 4 </ b> D formed in the outboard side flange 18 of the hub 4. The recessed portion 4D is a portion recessed from the flange surface 4B. The auxiliary lip 37 can bounce off foreign matters coming from the outside and minimize foreign matters reaching the side lip 34.

  In this embodiment, the auxiliary lip 37 does not contact the recess 4D of the outboard flange 18, and an annular and labyrinth-like gap 4E is provided between the tip edge of the auxiliary lip 37 and the recess 4D. However, the auxiliary lip 37 may contact the recess 4D and slide relative to the recess 4D.

  The cylindrical portion 26 of the sealing device 20 has a proximal end surface 38 that is continuous with the annular wall portion 28, and a distal end surface 40 that is on the opposite side of the annular wall portion 28. The proximal end surface 38 and the distal end surface 40 are orthogonal to the central axis Ax of the hub bearing 1 and are parallel to each other.

  In this embodiment, a convex portion 29 protruding from the base end surface 38 of the tubular portion 26 is formed on the outer surface 28A on the outboard side of the annular wall portion 28 (the surface on the side opposite to the end portion 8A of the outer ring 8). ing. The convex portion 29 has a flat surface, and a step is provided between the flat surface and the base end surface 38 of the tubular portion 26.

  FIG. 4 shows a state in which a plurality of sealing devices 20 are stacked on the table St. In a manufacturing process, a conveyance process, or an installation process, when a large number of sealing devices 20 are stacked, it is desirable that the stability be high. In this embodiment, the cylindrical portion 26 of the sealing device 20 has a proximal end surface 38 and a distal end surface 40 which are orthogonal to the central axis Ax of the hub bearing 1 (that is, the central axis of the sealing device 20) and parallel to each other. Accordingly, a large number of sealing devices 20 can be stably stacked so that the distal end surface 40 of the cylindrical portion 26 of the sealing device 20 is placed on the proximal end surface 38 of the cylindrical portion 26 of another sealing device 20 of the same type. Is possible.

  In this embodiment, the cylindrical end portion 8 </ b> A of the outer ring 8 of the hub bearing 1 is fitted into the cylindrical portion 26 of the sealing device 20. For this reason, the cylindrical part 26 of the sealing device 20 can be formed to have a certain size. That is, it is possible to increase the area of the base end surface 38 and the front end surface 40 of the cylindrical portion 26. This improves the stability when the sealing device 20 is stacked.

  FIG. 5 shows a state in use of the sealing device 60 according to the comparative example. In the sealing device 60, the cylindrical portion 66 is fitted into the cylindrical end portion 8 </ b> A of the outer ring 8, contrary to the embodiment. Therefore, the cylindrical portion 66 of the comparative example has a smaller diameter than the cylindrical portion 26 of the embodiment. When stacking a plurality of sealing devices 60, the lower end of the cylindrical portion 66 is placed on the flat surface 68 of another sealing device 60. In this case, the diameter of the cylindrical portion 66 itself is small, and the contact area between the sealing devices 60 must be reduced. Compared with the sealing device 60 of the comparative example, the sealing device 20 of the embodiment can be stably stacked.

  In the comparative example of FIG. 5, the cylindrical portion 66 is fitted into the cylindrical end portion 8 </ b> A of the outer ring 8, so that the lips 32, 34, and 36 have such a length as to perform their functions. The distance L between the outer peripheral surface 4A of the hub 4 and the outer ring 8 must be long to some extent. However, in this embodiment, the cylindrical end portion 8 </ b> A of the outer ring 8 of the hub bearing 1 is fitted into the cylindrical portion 26 of the sealing device 20. Therefore, as shown in FIG. 2, even when the distance L between the outer peripheral surface 4A of the hub 4 and the outer ring 8 is small, the lips 32, 34, and 36 are designed to have such a length that they can perform their respective functions. Is easy.

  In this embodiment, the inner annular portion 30 interposed between the tubular portion 26 and the lips 32, 34, 36 includes an outer surface 28 </ b> A on the outboard side of the annular wall portion 28, and a distal end surface 40 of the tubular portion 26. Exists in the space between, and does not protrude outside that space. That is, the inner annular portion 30 does not protrude outward from the distal end surface 40 of the tubular portion 26 in a direction parallel to the central axis Ax of the hub bearing 1. Therefore, when a plurality of sealing devices 20 are stacked, the inner annular portion 30 does not come into contact with other sealing devices, and the stability when the sealing devices 20 are stacked can be improved. On the other hand, if the inner annular portion 30 has a portion protruding downward in the figure from the tip surface 40, the portion of the other sealing device 20 (for example, the portion directly below the sealing device 20 (for example, The side lip 34 or the inner annular portion 30) may come into contact, and stability during stacking may be hindered.

  The length, orientation, and position of each of the lips 32, 34, 36 are designed so that the lips 32, 34, 36 do not contact the other sealing device 20. In short, when a plurality of sealing devices 20 are stacked, the distal end surface 40 of the cylindrical portion 26 of the sealing device 20 and the base end surface 38 of the cylindrical portion 26 of the other sealing device 20 are in contact with each other, and the other portions are in contact with each other. Not to be considered.

  Grease G may be applied to the radially inner surfaces 32A, 34A, 36A of the lips 32, 34, 36. In this case, considering the thickness of the grease G so that the grease G on the surfaces 32A, 34A, and 36A does not contact the other sealing device 20, the length, direction, and position of each of the lips 32, 34, and 36 are considered. Is preferably designed.

  In this embodiment, since the cylindrical part 26 has two concentric cylinders 24A and 24B which are formed by the reinforcing ring 24 and overlap in the radial direction, a large width W of the cylindrical part 26 can be secured. For this reason, it is possible to provide the front end surface 40 of a large area in the cylindrical part 26, and can further improve the stability of the sealing device 20 stacked.

  In this embodiment, the outer wall 28A on the outboard side of the annular wall portion 28 (the surface opposite to the end portion 8A of the outer ring 8) has a convex portion 29 that protrudes from the base end surface 38 of the cylindrical portion 26. Is formed. Since the convex part 29 which protrudes rather than the base end surface 38 is provided in the radial inside of the base end surface 38 on which the front end surface 40 of the other sealing device 20 is placed, the radial movement of the stacked sealing devices 20 is performed. (That is, horizontal movement) is suppressed. Therefore, the stability of the stacked sealing devices 20 can be further improved. Even if a large number of sealing devices 20 are stacked, there is little risk of the stacking being lost. When the plurality of sealing devices 20 are stacked, it is preferable to design the dimensions of the convex portions 29 so that the convex portions 29 do not come into contact with other sealing devices 20 (particularly the thick portion 22A of the cylindrical portion 26).

  Further, in this embodiment, the auxiliary lip 37 can rebound foreign matters coming from the outside (in FIG. 2, an example of the direction of foreign matter flow from the outside is indicated by an arrow F). Therefore, foreign matter that reaches the side lip 34 can be minimized.

  In this embodiment, the diameter D1 of the portion where the auxiliary lip 37 and the base end surface 38 of the tubular portion 26 intersect is equal to or larger than the outer diameter D2 of the distal end surface 40 of the tubular portion 26. Accordingly, the distal end surface 40 of the cylindrical portion 26 of the sealing device 20 can be brought into contact with the proximal end surface 38 inside the auxiliary lip 37 of another sealing device 20 of the same type, and the stability of the stacked sealing devices 20 can be stabilized. The sex can be further enhanced.

2nd Embodiment FIG. 6: is a fragmentary sectional view at the time of stacking of the sealing device 20 which concerns on 2nd Embodiment of this invention. In the drawings subsequent to FIG. 6, the same reference numerals are used to indicate the same components as those in the first embodiment, and the components will not be described in detail.

  In this embodiment, the base end surface 38 is flush with the outer surface 28A on the outboard side of the annular wall portion 28 (the surface opposite to the end portion 8A of the outer ring 8). That is, the convex portion 29 of the first embodiment is not provided.

  A diameter D1 of a portion where the auxiliary lip 37 and the base end surface 38 of the tubular portion 26 intersect is equal to or larger than the outer diameter D2 of the distal end surface 40 of the tubular portion 26. Therefore, the distal end surface 40 of the cylindrical portion 26 of the sealing device 20 can be brought into contact with the proximal end surface 38 inside the auxiliary lip 37 of another sealing device 20 of the same type, and the convex portion 29 is not provided. However, to some extent, movement of the stacked sealing devices 20 in the radial direction (that is, movement in the horizontal direction) is suppressed.

  As shown in FIG. 2, when the sealing device 20 is attached to the hub bearing 1, the end portion 8 </ b> A of the outer ring 8 of the hub bearing 1 is fitted into the cylindrical portion 26. At this time, the annular wall portion 28 receives an external force from, for example, an attachment jig, and the inner surface of the annular wall portion 28 is brought into contact with the end surface of the end portion 8 </ b> A of the outer ring 8. If the annular wall portion 28 is provided with the convex portion 29 having a large thickness, it may be difficult to apply an external force to the annular wall portion 28. However, when the convex portion 29 is not provided on the annular wall portion 28 as in the second embodiment, it becomes easy to attach the sealing device 20 to the outer ring 8 by applying an external force to the annular wall portion 28. .

3rd Embodiment FIG. 7: is a fragmentary sectional view at the time of stacking of the sealing device 20 which concerns on 3rd Embodiment of this invention.

  This embodiment is a modification of the second embodiment, and the diameter D1 of the portion where the auxiliary lip 37 and the base end surface 38 of the tubular portion 26 intersect is substantially equal to the outer diameter D2 of the distal end surface 40 of the tubular portion 26. Therefore, even if the convex portion 29 is not provided, there is almost no radial movement (that is, horizontal movement) of the stacked sealing devices 20. Even if a large number of sealing devices 20 are stacked, there is little risk of the stacking being lost. For this purpose, preferably the difference between the diameter D1 and the outer diameter D2 is less than 1.5 mm.

  However, this embodiment may be modified to provide the convex portion 29 on the annular wall portion 28.

Other Modifications Embodiments of the present invention have been described above. However, 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. Examples are possible.

  The shape and number of lips (including auxiliary lips) of the sealing device 20 are not limited to those described above.

  In the above embodiment, the hub 4 that is an inner member is a stationary member, and the outer ring 8 that is an outer member is a rotating 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 rotate and the outer member may be stationary, or all of these members may rotate.

1 Hub bearing (rolling bearing)
Ax Center axis 2 Hole 4 Hub (inner member)
8 Outer ring (outer member)
8A End 10, 12 Ball 18 Outboard flange 20 Sealing device 22 Elastic ring 22A Thick part 24 Reinforcement ring 24A, 24B Cylinder 24C Connection part 26 Cylindrical part 27 Outer edge part 28 Annular wall part 28A Outer surface 29 Convex part 30 Inside Annular portion 32 Radial lips 34, 36 Side lip 37 Auxiliary lip 38 Base end surface 40 Front end surface

Claims (4)

A sealing device that is disposed 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,
A cylindrical portion having an inner peripheral surface having a central axis, the cylindrical end portion of the outer member of the rolling bearing being fitted into the inner peripheral surface, and a cylindrical portion contacting the outer peripheral surface of the end portion;
An annular wall portion that extends radially inward from the tubular portion and is opposed to an end face of the end portion of the outer member;
An inner annular portion extending radially inward of the annular wall and disposed radially inward of the end of the outer member;
At least one lip extending from the inner annular portion toward the inner member of the rolling bearing;
It is arranged on the outer side in the radial direction than the cylindrical part, extends in the direction opposite to the cylindrical part, and toward the flange that protrudes radially outward from the outer member among the inner members of the rolling bearing. An auxiliary lip that extends,
The cylindrical portion has a base end surface connected to the annular wall portion and a front end surface on the opposite side of the annular wall portion, and the base end surface and the front end surface are orthogonal to the central axis. Parallel to each other,
The sealing device according to claim 1, wherein the inner annular portion does not protrude from the distal end surface of the cylindrical portion in a direction parallel to the central axis. An elastic ring formed of an elastic body and a reinforcing ring formed of a rigid body that reinforces the elastic ring;
2. The sealing device according to claim 1, wherein the cylindrical portion includes two concentric cylinders formed by the reinforcing ring, and the two cylinders overlap in a radial direction.   The annular wall portion has an outer surface that is opposite to the end portion of the outer member, and a convex portion that protrudes from the base end surface of the cylindrical portion is formed on the outer surface. The sealing device according to claim 1 or 2, characterized by the above.   The diameter of the portion where the auxiliary lip and the base end surface of the cylindrical portion intersect is equal to or greater than the outer diameter of the distal end surface of the cylindrical portion, and the difference between the diameter and the outer diameter is less than 1.5 mm. The sealing device according to any one of claims 1 to 3, wherein:

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