JP6960818B2 - Sealing device - Google Patents

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 has the function of contacting the outer peripheral surface of the inner ring of the bearing or the outer peripheral surface of the component fixed to the inner ring to seal the lubricant inside the bearing, and the two side lips contact the flange of the inner ring. Therefore, it has a function of sealing so that foreign matter such as water and dust does not enter the inside of the bearing from the outside.

Japanese Patent No. 3991200

With the miniaturization of machine parts, especially rolling bearings, it is preferable to miniaturize the sealing device as much as possible.

Therefore, the present invention provides a sealing device capable of further miniaturization.

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 has an inner rigid body portion and an outer elastic body portion that contacts the outer peripheral surface of the inner rigid body portion and covers the outer peripheral surface of the inner rigid body portion over the entire circumference , and the inner rigid body portion covers the inner peripheral surface. The inner peripheral surface of the inner rigid body portion is fitted with a cylindrical end portion of the outer member of the rolling bearing, and the inner peripheral surface of the inner rigid body portion is formed on the outer peripheral surface of the end portion. A cylindrical portion that comes into contact, an annular wall portion that extends inward in the radial direction from the tubular portion and faces the end surface of the end portion of the outer member, and an annular wall portion that extends inward in the radial direction of the annular wall portion. An inner annular portion located radially inside the outer member and at least one inner lip formed of an elastic body extending from the inner annular portion toward the inner member of the rolling bearing. When the of the tubular portion Ru extending from an outer elastic portion radially inwardly toward the end portion of the outer member, and an outer lip formed by the elastic body. A tapered surface or a curved surface whose diameter becomes smaller toward the annular wall portion is not formed at the end of the inner peripheral surface of the inner rigid body portion of the tubular portion. The outer elastic body portion of the tubular portion covers the inner rigid body portion of the tubular portion over the entire circumference and does not come into contact with the end portion of the outer member. The outer lip is separated from the inner rigid body portion of the tubular portion and contacts the entire circumference of the end portion of the outer member.

In this embodiment, the cylindrical end of the outer member of the rolling bearing is fitted into the inner peripheral surface of the rigid portion of the tubular portion, and most of the sealing device is arranged radially inside the tubular portion. There is. Therefore, even if the rolling bearing is miniaturized, it is easy to attach the sealing device to the outer member of the rolling bearing. Further, the outer lip made of an elastic material, extends toward the cylindrical end portion of the outer side member, Runode be contacted over the entire circumference of the end of the outer member, the rigid portion is protected from the external environment. Therefore, it is possible to suppress the progress of rust on the rigid body portion, and it is also possible to suppress foreign matter from entering the gap between the rigid body portion of the tubular portion and the end portion of the outer member of the rolling bearing. be.

At the end of the inner peripheral surface the rigid portion of the pre-Symbol cylindrical portion, the tapered surface or a curved surface diameter increases toward the annular wall portion is reduced it is formed, the outer lip, the cylindrical portion It is away from said inner rigid part of. Therefore , it is easy to fit the cylindrical end portion of the outer member of the rolling bearing into the inner peripheral surface of the inner rigid body portion of the tubular portion by the tapered surface or the curved surface. Further, since the outer lip is away from the inner rigid portion of the cylindrical portion, it is easy to the outer lip is elastically deformed against its inner rigid portion. Therefore, it is even easier to fit the cylindrical end of the outer member of the rolling bearing into the inner peripheral surface of the inner rigid body portion of the tubular portion.

It is a partial cross-sectional view of an example of a rolling bearing in which the sealing device according to a plurality of embodiments of the present invention is used. It is a partial cross-sectional view at the time of use of the sealing device which concerns on 1st Embodiment of this invention. It is a partially enlarged sectional view at the time of using the sealing device which concerns on 1st Embodiment. It is a partially enlarged sectional view at the time of using the sealing device which concerns on a comparative example. It is a partially enlarged sectional view at the time of non-use of the sealing device which concerns on 1st Embodiment. It is a partially enlarged sectional view at the time of non-use of the sealing device which concerns on a comparative example. It is a partial cross-sectional view at the time of use of the sealing device which concerns on 2nd Embodiment of this invention. It is a partial cross-sectional view at the time of use of the sealing device which concerns on 3rd Embodiment of this invention. It is a partial cross-sectional view at the time of use of the sealing device which concerns on 4th Embodiment of this invention. It is a partial cross-sectional view at the time of use of the sealing device which concerns on 5th Embodiment of this 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 a hub bearing for an automobile which is an example of a rolling bearing in which the sealing device according to the embodiment of the present invention is used. However, the application of the present invention is not limited to hub bearings, and the present invention can be applied to other rolling bearings. Further, in the following description, the hub bearing is a ball bearing, but 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. The present invention is also applicable. The present invention is also applicable to rolling bearings used in machines other than automobiles.

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

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

The 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 side portion with respect to the central axis Ax is shown. Although not shown in detail, the upper side of FIG. 1 is the outside (outboard side) where the wheels of the automobile are arranged, and the lower side is the inside (inboard side) where the differential gears and the like are arranged. The outside and the inside shown in FIG. 1 mean the outside and the inside 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 that projects radially outward from the outer ring 8. Wheels can be attached to the outboard side flange 18 by means of hub bolts 19.

A sealing device 20 for sealing the gap between the outer ring 8 and the hub 4 is arranged 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 arranged. By the action of these sealing devices 20 and 21, the outflow of grease, that is, the lubricant from the inside of the hub bearing 1 is prevented, and foreign matter (water (including muddy water or salt water)) from the outside to the inside of the hub bearing 1 is prevented. And the inflow of dust) is prevented. In FIG. 1, the arrow F shows an example of the direction of the flow of foreign matter from the outside.

The sealing device 20 is arranged 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 8A on the outboard side of the outer ring 8 of the hub bearing 1 and an outer peripheral surface 4A in the vicinity of the ball 10 of the hub 4 of the hub bearing 1. , The hub 4 is arranged in a space surrounded by a flange surface 4B extending outward from the outer peripheral surface 4A and an arc surface 4C connecting the outer peripheral surface 4A and the flange surface 4B. The flange surface 4B is the surface of the outboard side flange 18 on the inboard side. Although the sealing device 20 is annular, only the left side portion thereof is shown in FIG.

The sealing device 20 has an elastic body, for example, an elastic ring 22 made of an elastomer, and a rigid body for reinforcing the elastic ring 22, for example, a single reinforcing ring 24 made of metal. That is, the sealing device 20 has a double structure having an elastic ring 22 and a reinforcing ring 24. 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 tubular portion 26, an annular wall portion 28, an inner annular portion 30, a radial lip (inner lip) 32, two side lips (inner lips) 34 and 36, and an outer lip 37. Have.

The tubular portion 26 is a cylindrical portion centered on the central axis Ax (see FIG. 1). The tubular portion 26 has a cylindrical outer elastic body portion 26A that is a part of the elastic ring 22 and a cylindrical inner rigid body portion 26B that is a part of the reinforcing ring 24. The inner rigid body portion 26B is concentrically arranged inside the outer elastic body portion 26A, and the outer elastic body portion 26A contacts the outer peripheral surface of the inner rigid body portion 26B and covers the outer peripheral surface of the inner rigid body portion 26B over the entire circumference. cover. The inner rigid body portion 26B has an inner peripheral surface of the tubular portion 26, and the cylindrical end portion 8A of the outer ring 8 of the hub bearing 1 is fitted (that is, press-fitted) to the inner peripheral surface by a tightening method. , The inner peripheral surface comes into contact with the outer peripheral surface of the end portion 8A. In this way, the tubular portion 26 is fixed to the end portion 8A.

The annular wall portion 28 extends inward in the radial direction 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 a portion that is a part of the elastic ring 22 and a portion that is a part of the reinforcing ring 24, and the portion corresponding to the reinforcing ring 24 is opposed to the end surface of the end portion 8A of the outer ring 8. , Contact its end face.

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

Each of the radial lip 32 and the side lips 34 and 36 is a part of the elastic ring 22, is formed only from the elastic body, and is a thin plate-shaped annular ring extending from the portion corresponding to the elastic ring 22 of the inner annular portion 30. And each tip comes into contact with the hub 4. Since the hub 4 rotates while the sealing device 20 is attached to the fixed outer ring 8, the lips 32, 34, 36 slide with respect 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 4A in the vicinity of the ball 10 of the hub 4. The radial lip 32 extends inward in the radial direction and toward the inboard side, and mainly serves to prevent the outflow of the lubricant from the inside of the hub bearing 1.

The side lips 34 and 36 extend laterally (outboard side) and radially outward from the portion of the inner annular portion 30 corresponding to the elastic ring 22. 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 the inflow of foreign matter from the outside into the inside of the hub bearing 1. The side lip 36 has a backup function of blocking foreign matter that has slipped through the side lip 34 and has flowed in. Since the side lip 36 exists between the radial lip 32 and the side lip 34, it can also be called an intermediate lip.

The outer lip 37 extends radially inward from the outer elastic body portion 26A of the tubular portion 26 toward the end portion 8A of the outer ring 8 to protect the inner rigid body portion 26B of the tubular portion 26 over the entire circumference. The outer lip 37 is a part of the elastic ring 22 and is formed only from the elastic body. The outer lip 37 protects the inner rigid body portion 26B from the external environment, suppresses the progress of rust on the inner rigid body portion 26B, and also suppresses the progress of rust on the inner rigid body portion 26B and the end portion of the inner rigid body portion 26B of the tubular portion 26 and the outer ring 8 of the hub bearing 1. It suppresses foreign matter from entering the gap with 8A.

At the end of the inner peripheral surface of the inner rigid body portion 26B of the tubular portion 26, a tapered surface 26C whose diameter decreases toward the annular wall portion 28 is formed. The tapered surface 26C makes it easy to fit the cylindrical end 8A of the outer ring 8 of the hub bearing 1 into the inner peripheral surface of the inner rigid body portion 26B of the tubular portion 26. However, instead of the tapered surface 26C, a curved surface whose diameter becomes smaller toward the annular wall portion 28 may be formed.

Outer lip 37 is separated from the inner rigid portion 26B of the tubular portion 26. In particular, in this embodiment, the base end portion 37a of the outer lip 37 exists at a position away from the tip end portion 26Ba of the inner rigid body portion 26B.

FIG. 3 is an enlarged cross-sectional view showing details of the tubular portion 26 of the sealing device 20 according to this embodiment, which is attached to the end portion 8A of the outer ring 8. The outer lip 37 is not subjected to an external force when it is not in contact with the end portion 8A of the outer ring 8, and extends straight as shown by a virtual line. However, when the sealing device 20 is attached to the end portion 8A, the outer lip 37 comes into contact with the end portion 8A and receives a reaction force to be deformed as shown by a solid line. This amount of deformation, that is, the tightening allowance IN1, is shown in FIG.

FIG. 4 is an enlarged cross-sectional view showing the details of the tubular portion 26 of the sealing device of the comparative example, which is attached to the end portion 8A of the outer ring 8. In this comparative example, the tubular portion 26 has a double structure having an outer elastic body portion 26A and an inner rigid body portion 26B arranged inside the outer elastic body portion 26A. However, instead of the outer lip 37, a protrusion 40 is formed on the inner peripheral surface of the end portion of the outer elastic body portion 26A. The protrusion 40 is brought into contact with the outer ring 8 over the entire circumference of the end portion 8A. The tip portion 26Bb of the inner rigid body portion 26B is curved to reinforce the protrusion 40 and extends to the region of the protrusion 40, and the protrusion 40 is in contact with the curved portion of the inner rigid body portion 26B.

The protrusion 40 is not subjected to an external force when it is not in contact with the end portion 8A of the outer ring 8, and is protruding as shown by a virtual line. However, when the sealing device 20 is attached to the end portion 8A, the protrusion 40 comes into contact with the end portion 8A and receives a reaction force to be deformed so as to be in close contact with the outer peripheral surface of the end portion 8A. This amount of deformation, that is, the tightening allowance IN2 is shown in FIG.

As can be easily understood by comparing FIGS. 3 and 4, according to the sealing device 20 according to this embodiment, it is possible to obtain a tightening allowance IN1 larger than the tightening allowance IN2 of the sealing device of the comparative example. Therefore, the outer lip 37 of this embodiment can be reliably contacted over the entire circumference of the end portion 8A of the outer ring 8 and can suppress the invasion of foreign matter. In particular, even if the outer ring 8 is deformed or the sealing device 20 is eccentric to the outer ring 8, the outer lip 37 can be reliably contacted over the entire circumference of the end portion 8A of the outer ring 8.

Further, in the comparative example of FIG. 4, when the sealing device is attached to the end portion 8A of the outer ring 8, it is not easy to fit the end portion 8A into the tubular portion 26 so as to get over the protrusion 40. If the length of the protrusion 40 in the direction of the central axis Ax or the tightening allowance IN2 is reduced, it may be easier to fit the end portion 8A into the cylindrical portion 26, but the sealing performance of the protrusion 40 is improved. descend. On the other hand, when the sealing device 20 according to this embodiment is attached to the end portion 8A of the outer ring 8, the outer lip 37 is easily deformed even if it is long, so that the end portion 8A is attached to the tubular portion 26 of the sealing device 20. Easy to fit.

Further, in the comparative example of FIG. 4, after the sealing device is attached to the end portion 8A of the outer ring 8, the protrusion 40 receives a large reaction force from the end portion 8A, so that the inner rigid body portion 26B is deformed and the reinforcing ring 24 is formed. A gap may be formed between the surface and the end portion 8A, which may reduce the sealing performance. On the other hand, after the sealing device 20 according to this embodiment is attached to the end portion 8A of the outer ring 8, the outer lip 37 does not receive a large reaction force from the end portion 8A, so that there is little possibility that the sealing performance is deteriorated.

FIG. 5 is an enlarged cross-sectional view showing details of the tubular portion 26 of the sealing device 20 according to this embodiment, which is not attached to the end portion 8A of the outer ring 8. FIG. 6 is an enlarged cross-sectional view showing the details of the tubular portion 26 of the sealing device of the above comparative example, which is not attached to the end portion 8A of the outer ring 8.

The sealing device 20 according to this embodiment can be manufactured, for example, by press working or injection molding. That is, by arranging the reinforcing ring 24 in the mold and then molding the elastic ring 22 with the mold, it is possible to manufacture the sealing device 20 in which the reinforcing ring 24 and the elastic ring 22 are in close contact with each other. When the sealing device of the comparative example shown in FIG. 6 is manufactured by press working or injection molding, the curved portion of the inner rigid body portion 26B and the adjacent portion 41 of the protrusion 40 serve as the boundary surface between the mold and the elastic ring 22. In this case, it is difficult to spread the elastomer, which is the material of the elastic ring 22, in the mold to a necessary and sufficient extent. That is, burrs or sink marks of the elastomer may occur. If burrs of the elastomer are generated in the vicinity of the adjacent portion 41, burrs adhere to the inner peripheral surface of the inner rigid body portion 26B, and the outer ring 8 of the hub bearing 1 is attached to the inner peripheral surface of the inner rigid body portion 26B of the cylindrical portion 26. There is a risk of hindering the fitting of the cylindrical end 8A. On the other hand, if an elastomer sink mark occurs in the vicinity of the adjacent portion 41, the strength of the protrusion 40 may be insufficient.

On the other hand, in the case of the sealing device 20 according to the embodiment shown in FIG. 5, the cylindrical surface 38 between the base end portion 37a of the outer lip 37 and the tip end portion 26Ba of the inner rigid body portion 26B has a mold and elasticity. It becomes the boundary surface with the ring 22. Therefore, it is easy to spread the elastomer, which is the material of the elastic ring 22, in the mold to a necessary and sufficient extent. That is, it is possible to suppress the generation of burrs and sink marks of the elastomer. Even if burrs of the elastomer occur near the tip portion 26Ba of the inner rigid body portion 26B, burrs are unlikely to adhere to the inner peripheral surface of the inner rigid body portion 26B, so that the inside of the inner rigid body portion 26B of the tubular portion 26 It is easy to fit the cylindrical end 8A of the outer ring 8 of the hub bearing 1 on the peripheral surface.

As is clear from the above description, in this embodiment, the cylindrical end 8A of the outer ring 8 of the hub bearing 1 is fitted into the inner peripheral surface of the inner rigid body portion 26B of the tubular portion 26, and is a sealing device. Most of the 20 is arranged inside the tubular portion 26 in the radial direction. Therefore, even if the hub bearing 1 is miniaturized, the sealing device 20 can be easily attached to the outer ring 8 of the hub bearing 1.

On the other hand, when a part of the sealing device is fitted inside the end portion 8A of the outer ring 8, the inner lip (for example, radial lip 32) of the sealing device is sufficient so as to secure sufficient sealing performance of the sealing device. The inner diameter of the end portion 8A of the outer ring 8 must be increased in order to have a large size. If the inner diameter of the end portion 8A of the outer ring 8 is reduced in order to reduce the size of the hub bearing 1, there is a possibility that sufficient sealing performance of the sealing device cannot be ensured. In this embodiment, since the end portion 8A of the outer ring 8 is fitted into the inner peripheral surface of the inner rigid body portion 26B of the tubular portion 26, the end portion of the outer ring 8 is fitted while ensuring sufficient sealing performance of the sealing device. The inner diameter of 8A can be reduced, which can contribute to the miniaturization of the hub bearing 1.

Further, when a part of the sealing device is fitted inside the end portion 8A of the outer ring 8, a part of the reinforcing ring is brought into contact with the inner peripheral surface of the end portion 8A. In this case, it is usual to increase the length in the direction of the central axis Ax of the portion of the reinforcing ring in contact with the inner peripheral surface of the end portion 8A, and for this reason, the length in the direction of the central axis Ax of the sealing device. Becomes larger. Further, in order to secure the contact pressure with respect to the inner peripheral surface of the end portion 8A, the portion of the reinforcing ring press-fitted into the end portion 8A is usually formed into a bent shape, and for this purpose, the forming step of the reinforcing ring is performed. It gets complicated. In this embodiment, since the end portion 8A of the outer ring 8 is fitted into the inner peripheral surface of the inner rigid body portion 26B of the tubular portion 26, the length in the direction of the central axis Ax of the sealing device 20 can be reduced. .. Further, since the reinforcing ring 24 does not require a portion to be press-fitted into the end portion 8A, the shape of the reinforcing ring 24 can be simplified and the reinforcing ring can be easily formed.

Further, in this embodiment, since the outer lip 37 formed of the elastic body covers the inner rigid body portion 26B of the tubular portion 26 and extends toward the cylindrical end portion 8A of the outer ring 8, the inner rigid body portion 26B Is protected from the external environment. Therefore, it is possible to suppress the progress of rust on the inner rigid body portion 26B, and foreign matter enters the gap between the inner rigid body portion 26B of the tubular portion 26 and the end portion 8A of the outer ring 8 of the hub bearing 1. It is possible to suppress.

Further, in this embodiment, a tapered surface 26C whose diameter becomes smaller toward the annular wall portion 28 is formed at the end of the inner peripheral surface of the inner rigid body portion 26B of the tubular portion 26. The tapered surface 26C makes it easy to fit the cylindrical end 8A of the outer ring 8 of the hub bearing 1 into the inner peripheral surface of the inner rigid body portion 26B of the tubular portion 26. Further, since the outer lip 37 is separated from the inner rigid portion 26B of the tubular portion 26, it is easy to the outer lip 37 is elastically deformed against its inner rigid portion 26B. Therefore, it is easier to fit the cylindrical end 8A of the outer ring 8 of the hub bearing 1 into the inner peripheral surface of the inner rigid body portion 26B of the tubular portion 26.

Second Embodiment FIG. 7 is a partial cross-sectional view of the sealing device 20 according to the second embodiment of the present invention when used. In the drawings after FIG. 7, the same reference numerals are used to show the components common to the first embodiment, and these components will not be described in detail.

In this embodiment, the tip portion 26D of the inner rigid body portion 26B of the tubular portion 26 is formed as a flange. At the end of the inner peripheral surface of the inner rigid body portion 26B, a curved surface 26E whose diameter decreases toward the annular wall portion 28 is formed.

Outer lip 37 is separated from the inner rigid portion 26B of the tubular portion 26. In particular, in this embodiment, the base end portion 37a of the outer lip 37 exists at a position away from the tip end portion 26D of the inner rigid body portion 26B.

Also in this embodiment, even if the hub bearing 1 is miniaturized, the sealing device 20 can be easily attached to the outer ring 8 of the hub bearing 1. Further, this embodiment can also contribute to the miniaturization of the hub bearing 1 by reducing the inner diameter of the end portion 8A of the outer ring 8 while ensuring sufficient sealing performance of the sealing device. Further, since the outer lip 37 formed of the elastic body, it is possible to suppress the progress of rust on the inner rigid body portion 26B, and the inner rigid body portion 26B of the tubular portion 26 and the outer ring 8 of the hub bearing 1 It is possible to prevent foreign matter from entering the gap with the end portion 8A.

Further, in this embodiment, a curved surface 26E whose diameter becomes smaller toward the annular wall portion 28 is formed at the end of the inner peripheral surface of the inner rigid body portion 26B of the tubular portion 26. The curved surface 26E makes it easy to fit the cylindrical end 8A of the outer ring 8 of the hub bearing 1 into the inner peripheral surface of the inner rigid body portion 26B of the tubular portion 26. Further, since the outer lip 37 is separated from the inner rigid portion 26B of the tubular portion 26, it is easy to the outer lip 37 is elastically deformed against its inner rigid portion 26B. Therefore, it is easier to fit the cylindrical end 8A of the outer ring 8 of the hub bearing 1 into the inner peripheral surface of the inner rigid body portion 26B of the tubular portion 26.

Third Embodiment FIG. 8 is a partial cross-sectional view of the sealing device 20 according to the third embodiment of the present invention when used. In this embodiment, the base end portion 37a of the outer lip 37 is adjacent the distal end 26Ba of the inner rigid portion 26B, the outer lip 37 is separated from the inner rigid portion 26B of the cylindrical portion 26 .. Therefore, it is easy to elastically deform the outer lip 37 with respect to the inner rigid body portion 26B, and the cylindrical end portion 8A of the outer ring 8 of the hub bearing 1 is provided on the inner peripheral surface of the inner rigid body portion 26B of the tubular portion 26. Easy to fit.

In the case of the sealing device 20 according to this embodiment, the inner peripheral surface of the outer lip 37 is the boundary surface between the mold and the elastic ring 22. In this case as well, it is easy to spread the elastomer, which is the material of the elastic ring 22, in the mold to a necessary and sufficient extent. That is, it is possible to suppress the generation of burrs and sink marks of the elastomer. Even if burrs of the elastomer occur near the tip portion 26Ba of the inner rigid body portion 26B, burrs are unlikely to adhere to the inner peripheral surface of the inner rigid body portion 26B, so that the inside of the inner rigid body portion 26B of the tubular portion 26 It is easy to fit the cylindrical end 8A of the outer ring 8 of the hub bearing 1 on the peripheral surface.

Also in this embodiment, even if the hub bearing 1 is miniaturized, the sealing device 20 can be easily attached to the outer ring 8 of the hub bearing 1. Further, this embodiment can also contribute to the miniaturization of the hub bearing 1 by reducing the inner diameter of the end portion 8A of the outer ring 8 while ensuring sufficient sealing performance of the sealing device. Further, since the outer lip 37 formed of the elastic body, it is possible to suppress the progress of rust on the inner rigid body portion 26B, and the inner rigid body portion 26B of the tubular portion 26 and the outer ring 8 of the hub bearing 1 It is possible to prevent foreign matter from entering the gap with the end portion 8A.

Fourth Embodiment FIG. 9 is a partial cross-sectional view of the sealing device 20 according to the fourth embodiment of the present invention when used. In this embodiment, in addition to the outer lip 37, an additional outer lip 42 is provided.

The outer lip 42 extends radially inward from the outer elastic body portion 26A of the tubular portion 26 toward the end portion 8A of the outer ring 8 and surrounds the outer lip 37 over the entire circumference. The outer lip 37 is a part of the elastic ring 22 and is formed only from the elastic body. By providing the double outer lips 37 and 42 in this way, the inner rigid body portion 26B is protected from the external environment, the progress of rust on the inner rigid body portion 26B is more reliably suppressed, and the tubular portion 26 is provided. It is possible to more reliably suppress foreign matter from entering the gap between the inner rigid body portion 26B and the end portion 8A of the outer ring 8 of the hub bearing 1. The number of outer lips may be further increased.

Fifth Embodiment FIG. 10 is a partial cross-sectional view of the sealing device 21 according to the fifth embodiment of the present invention when used. The first to fourth embodiments relate to the sealing device 20 on the outboard side (see FIG. 1), while the fifth embodiment relates to the sealing device 21 on the inboard side.

In this embodiment, the end portion 8B of the outer ring 8 of the hub bearing 1 on the inboard side is formed in a cylindrical shape, and the cylindrical portion of the outer ring 8 is formed on the inner peripheral surface of the inner rigid body portion 26B of the tubular portion 26 of the sealing device 20. The shaped end portion 8B is fitted (that is, press-fitted) by a tightening method, and the inner peripheral surface contacts the outer peripheral surface of the end portion 8B. In this way, the tubular portion 26 is fixed to the end portion 8B.

A slinger, that is, a rotary seal member 44 is fixed to the inner ring 6 (inner member). The rotary seal member 44 has a cylindrical portion 46 into which the inner ring 6 is fitted (that is, press-fitted), and a disk portion 48 extending from an end portion of the cylindrical portion 46. The rotary seal member 44 is made of a rigid body, for example, metal. When the inner ring 6 is rotated, the rotation seal member 44 rotates together with the inner ring 6.

A part of the sealing device 21 is arranged in a space surrounded by a cylindrical end portion 8B on the inboard side of the outer ring 8 of the hub bearing 1 and a rotary sealing member 44. Although the sealing device 21 is annular, only the left side portion thereof is shown in FIG.

The tips of the radial lip 32 and the side lips 34, 36 of the sealing device 21 come into contact with the rotary sealing member 44. While the sealing device 21 is attached to the fixed outer ring 8, the inner ring 6 and the rotary seal member 44 rotate, so that the lips 32, 34, 36 slide with respect to the rotary seal member 44.

The radial lip 32 comes into contact with the cylindrical portion 46 of the rotary seal member 44. The radial lip 32 extends inward in the radial direction and toward the outboard side, and mainly serves to prevent the outflow of the lubricant from the inside of the hub bearing 1. The side lips 34 and 36 come into contact with the disk portion 48 of the rotary seal member 44. The side lips 34 and 36 mainly play a role of preventing the inflow of foreign matter from the outside into the inside of the hub bearing 1.

The outer lip 37 extends radially inward from the outer elastic body portion 26A of the tubular portion 26 toward the end portion 8B of the outer ring 8 to protect the inner rigid body portion 26B of the tubular portion 26 over the entire circumference.

Also in this embodiment, even if the hub bearing 1 is miniaturized, the sealing device 21 can be easily attached to the outer ring 8 of the hub bearing 1. Further, this embodiment can also contribute to the miniaturization of the hub bearing 1 by reducing the inner diameter of the end portion 8B of the outer ring 8 while ensuring sufficient sealing performance of the sealing device. Further, since the outer lip 37 formed of the elastic body, it is possible to suppress the progress of rust on the inner rigid body portion 26B, and the inner rigid body portion 26B of the tubular portion 26 and the outer ring 8 of the hub bearing 1 It is possible to prevent foreign matter from entering the gap with the end portion 8B.

Further, in this embodiment, a tapered surface 26C whose diameter becomes smaller toward the annular wall portion 28 is formed at the end of the inner peripheral surface of the inner rigid body portion 26B of the tubular portion 26. The tapered surface 26C makes it easy to fit the cylindrical end 8B of the outer ring 8 of the hub bearing 1 into the inner peripheral surface of the inner rigid body portion 26B of the tubular portion 26. Further, since the outer lip 37 is separated from the inner rigid portion 26B of the tubular portion 26, it is easy to the outer lip 37 is elastically deformed against its inner rigid portion 26B. Therefore, it is easier to fit the cylindrical end 8B of the outer ring 8 of the hub bearing 1 into the inner peripheral surface of the inner rigid body portion 26B of the tubular portion 26.

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 within the technical scope of the present invention. An example is possible.

For example, the shape and number of inner lips of the sealing devices 20 and 21 are not limited to those described above.

The above embodiments may be combined as long as they do not conflict with each other. For example, the features according to the second to fourth embodiments (FIGS. 7 to 9) may be applied to the sealing device 21 on the inboard side.

In the above embodiment, the hub 4 and the inner ring 6 which are inner members are rotating members, 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 Hub bearing (rolling bearing)
4 Hub (inner member)
6 Inner ring (inner member)
8 Outer ring (outer member)
8A, 8B Ends 10, 12 Balls 20, 21 Sealing device 22 Elastic ring 24 Reinforcing ring 26 Cylindrical part 26A Outer elastic body part 26B Inner rigid body part 26Ba Tip part 26C Tapered surface 28 Circular wall part 30 Inner annular part 32 Radial lip (Inner lip)
34,36 Side lip (inner lip)
37 Outer lip 37a Base end 42 Outer lip 44 Rotating seal member

Claims (1)

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 has an inner rigid body portion and an outer elastic body portion that contacts the outer peripheral surface of the inner rigid body portion and covers the outer peripheral surface of the inner rigid body portion over the entire circumference , and the inner rigid body portion has an inner peripheral surface. cage, the end cylindrical of the outer member of the rolling bearing on the inner circumferential surface of the inner rigid portion is fitted, the cylinder of the inner peripheral surface of the inner rigid portion contacts the outer peripheral surface of the end portion Rigid body and
An annular wall portion extending inward in the radial direction from the tubular portion and facing the end surface of the end portion of the outer member, and an annular wall portion.
An inner annular portion extending inward in the radial direction of the annular wall portion and arranged radially inward with respect to the end portion of the outer member.
At least one inner lip formed of an elastic body extending from the inner annular portion toward the inner member of the rolling bearing.
Wherein said tubular portion Ru extending from an outer elastic portion radially inwardly toward the end portion of the outer member, and an outer lip formed by the elastic body,
At the end of the inner peripheral surface of the inner rigid body portion of the tubular portion, a tapered surface or a curved surface whose diameter becomes smaller toward the annular wall portion is formed.
The outer elastic body portion of the tubular portion covers the inner rigid body portion of the tubular portion over the entire circumference and does not come into contact with the end portion of the outer member.
The outer lip is separated from the inner rigid body portion of the tubular portion and contacts the entire circumference of the end portion of the outer member.
A sealing device characterized by that.

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