JP2022048883A - Sealing device - Google Patents

Abstract

To provide a sealing device which is high in protection performance from water to a sealing object.SOLUTION: A sealing device 20 for sealing a clearance between an inside member 4 and an outside member 8 of a rolling bearing 1 comprises: an attachment part 28 attached to the outside member of the rolling bearing; an inside circular disc part 30 arranged inside the attachment part in a radial direction; a grease slip 36 extending toward a cylinder portion of the inside member from the inside circular disc part; an inside side lip 40 extending toward a first flange face 4B of the inside member from the inside circular disc part; and an outside side lip 42 extending toward a second flange face 4C of the inside member from a position at the outside of the inside circular disc part. A ratio of the outside side lip with respect to a length of the outside side lip is higher than a ratio of a thickness of the inside side lip with respect to a length of the inside side lip, and a fastening margin of the outside side lip with respect to the second flange face is smaller than a fastening margin of the inside side lip with respect to the first flange face.SELECTED DRAWING: Figure 2

Description

The present invention relates to a sealing device.

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 is adapted to be secured to the outer ring of the hub bearing and has multiple lips extending towards the hub of the hub bearing. These lips have a grease lip that seals the lubricant (grease) inside the bearing, and a plurality of dust strips that prevent foreign substances such as water and dust from entering the inside of the bearing from the outside.

Japanese Patent No. 5778238

This type of sealing device may be used in watery environments (including muddy or salt water). For example, the case where a car runs with the lower part of the wheel submerged in water. In such a case, it is required to enhance the function of protecting water from entering the inside of the sealed object (for example, a bearing).

Therefore, the present invention provides a sealing device having high protection performance from water to a sealing target.

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. The inner member has a cylindrical portion, a first flange surface arranged radially outside the cylindrical portion, and a second flange surface arranged radially outside the first flange surface. Have. The sealing device includes a mounting portion attached to the outer member of the rolling bearing, an inner annular portion arranged radially inward from the mounting portion, and the inner member of the rolling bearing from the inner annular portion. A grease lip formed of an elastic material extending toward the cylindrical portion and an inner side lip formed of an elastic material extending from the inner ring portion toward the first flange surface of the inner member of the rolling bearing. And an outer side lip formed of an elastic material extending from a position outside the inner ring portion toward the second flange surface of the inner member of the rolling bearing. The inner side lip has a tip that slidably contacts the first flange surface, and the outer side lip has a tip that slidably contacts the second flange surface. The ratio of the thickness of the outer side lip to the length of the outer side lip is greater than the ratio of the thickness of the inner side lip to the length of the inner side lip. The tightening allowance of the outer side lip with respect to the second flange surface is smaller than the tightening allowance of the inner side lip with respect to the first flange surface.

In this embodiment, the tip of the inner side lip contacts the first flange surface of the inner member, and the tip of the outer side lip contacts the second flange surface of the inner member. Since the ratio of the thickness of the outer side lip to the length of the outer side lip is large, the outer side lip is not easily deformed. Therefore, even if a large water pressure is applied from the outside, it is difficult for water to pass between the outer side lip and the second flange surface, and the sealing device has high protection performance from water to the sealing target. On the other hand, since the tightening allowance of the outer side lip with respect to the second flange surface is small, the torque given to the inner member by the outer side lip is small. Further, since this tightening allowance is small, even if water passes between the outer side lip and the second flange surface, on the contrary, water is likely to be discharged through between the outer side lip and the second flange surface.

It is a partial cross-sectional view of an example of a rolling bearing in which the sealing device which concerns on embodiment of this invention is used. It is a partial cross-sectional view of the sealing device which concerns on embodiment of this invention. It is a partial cross-sectional view of the sealing device of the comparative example. It is a partial cross-sectional view of the sealing device of another comparative example. It is a partial cross-sectional view of the sealing device which concerns on other embodiment of this invention.

Hereinafter, various embodiments according to the present invention will be described with reference to the accompanying drawings. Drawing scales are not always accurate and some features may be exaggerated or omitted.

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 the hub bearing, 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 includes a hub (inner member) 4 having a hole 2 into which an axle (not shown) is inserted, an inner ring 6 attached to the hub 4, and an outer ring (outside) arranged outside the hub 4. (Member) 8, a plurality of balls 10 arranged in a row between the hub 4 and the outer ring 8, and a plurality of balls 12 arranged in a row between the inner ring 6 and the outer ring 8, and these balls are determined. It has a plurality of cages 14, 15 for holding in position.

While the outer ring 8 is fixed, the hub 4 and the inner ring 6 rotate with the rotation of the axle.

The common central axis Ax of the axle 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 projecting 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 for sealing 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 (including 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 cylindrical end 8A of the fixed outer ring 8 on the outboard side, and seals the gap between the hub 4 and the outer ring 8. Stop.

As shown in FIG. 2, the hub 4 of the hub bearing 1 has a cylindrical portion in the vicinity of the ball 10, and the cylindrical portion has an outer peripheral surface 4A. This cylindrical portion is surrounded by an outer ring 8.

The hub 4 further has a first flange surface 4B extending radially outward from the outer peripheral surface 4A and a second flange surface 4C extending radially outward from the first flange surface 4B. The first flange surface 4B has a flat surface 4B1 perpendicular to the central axis Ax of the hub bearing 1 and an arc surface 4B2 connecting the flat surface 4B1 and the outer peripheral surface 4A of the cylindrical portion. The arcuate surface 4B2 faces the end surface of the end portion 8A of the outer ring 8.

The second flange surface 4C has a flat surface 4C1 perpendicular to the central axis Ax of the hub bearing 1 and a curved surface 4C2 connecting the flat surface 4C1 and the flat surface 4B1 of the first flange surface 4B. An inclined surface may be provided instead of the curved surface 4C2. The second flange surface 4C is the surface of the outboard side flange 18 on the inboard side.

The sealing device 20 is attached to the cylindrical end 8A on the outboard side of the outer ring 8 of the hub bearing 1 and slidably contacts the hub 4. Although the sealing device 20 is annular, only the left side portion thereof is shown in FIG.

The sealing device 20 is a composite structure having an elastic ring 24 and a rigid ring 26. The elastic ring 24 is made of an elastic material, for example, an elastomer. The rigid ring 26 is made of a rigid body material, for example metal, to reinforce the elastic ring 24. A part of the rigid ring 26 is embedded in the elastic ring 24 and is in close contact with the elastic ring 24.

The sealing device 20 has a cylindrical portion 28, an inner annular portion 30, an outer annular portion 32, an outer cylindrical portion 34, and lips 36, 38, 40, 42.

The cylindrical portion 28 (mounting portion) is fitted (that is, press-fitted) to the end portion 8A of the outer ring 8 by a tightening method. The cylindrical portion 28 is composed of a portion having a U-shaped cross section of the rigid ring 26 and a portion of the elastic ring 24 embedded in this portion.

The inner annulus portion 30 extends radially inward from the cylindrical portion 28. The inner ring portion 30 is composed of a portion of the rigid ring 26 and a portion of the elastic ring 24.

The outer annulus portion 32 extends radially outward from the cylindrical portion 28 and comes into contact with the end face of the end portion 8A of the outer ring 8. The outer annulus portion 32 is composed of a portion of the rigid ring 26 and a portion of the elastic ring 24 arranged on both sides of this portion. The portion of the elastic ring 24 disposed between the portion of the rigid ring 26 and the end 8A prevents the rigid ring 26 from being exposed to water.

The outer cylindrical portion 34 extends from the outer edge of the outer annular portion 32 and surrounds the cylindrical portion 28. The outer cylindrical portion 34 is composed of a portion of the elastic ring 24, and is brought into contact with the outer peripheral surface of the end portion 8A of the outer ring 8. The outer cylindrical portion 34 is not always necessary.

Each of the lips 36, 38, 40, 42 is a thin annulus formed only of elastic material. The tips of the lips 36, 38, 40, 42 come 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 36, 38, 40, 42 slide with respect to the hub 4. In the figure, the shapes of the lips 36, 38, 40, and 42 elastically deformed in contact with the hub 4 are shown by virtual lines. The initial shapes of the lips 36, 38, 40, and 42 before deformation are shown by solid lines.

The lip 36, called a grease lip or radial lip, extends from the innermost edge of the inner annulus 30. The tip of the grease lip 36 comes into contact with the outer peripheral surface 4A of the cylindrical portion in the vicinity of the ball 10 of the hub 4. The grease lip 36 extends inward in the radial direction and toward the inboard side, and mainly reduces or prevents the outflow of the lubricant (grease that is a lubricant such as the ball 10 of the hub bearing 1) from the inside of the hub bearing 1. Take a role.

The lips 38 and 40 extend laterally (outboard side) from the inner annulus portion 30 and outward in the radial direction. The lip 40 is called a side lip or an axial lip. The tip of the lip 40 comes into contact with the flat surface 4B1 of the first flange surface 4B of the hub 4. The lip 38 is called an intermediate lip. The tip of the lip 38 comes into contact with the arcuate surface 4B2 of the first flange surface 4B. The intermediate lip 38 can also be called a side lip. The lips 38 and 40 mainly play a role of preventing the inflow of foreign matter from the outside into the inside of the hub bearing 1. The intermediate lip 38 has a backup function of blocking foreign matter that has slipped through the side lip 40 and has flowed in.

The lip 42 extends laterally (outboard side) and radially outward from the outer annulus 32. The lip 42 is called the outer side lip. The tip of the outer side lip 42 contacts the flat surface 4C1 of the second flange surface 4C of the hub 4. However, the tip of the outer side lip 42 may come into contact with the curved surface 4C2 of the second flange surface 4C. The outer side lip 42 mainly serves to prevent the inflow of foreign matter from the outside into the inside of the hub bearing 1.

The lips 38 and 40 can be referred to as inner side lips with respect to the outer side lips 42.

FIG. 3 shows a sealing device of a comparative example. In this comparative example, the tip of the outer side lip 42 does not contact the hub 4. Therefore, an annular gap 44 is provided between the tip of the outer side lip 42 and the second flange surface 4C. Since the gap 44 is small, it is difficult for external foreign matter to pass through the gap 44. However, for example, when the automobile runs with the lower part of the wheel submerged in water, the water passes through the gap 44. In such a case, when the water further gets over the inner side lips 40, 38 and the grease lip 36, the water reaches the space inside the bearing.

Compared to the comparative example of FIG. 3, according to the sealing device 20 according to the embodiment, the tips of the inner side lips 38 and 40 come into contact with the first flange surface 4B of the hub 4, and the tips of the outer side lips 42 further come into contact with each other. It contacts the second flange surface 4C of the hub 4. Since the number of lips that come into contact with the hub 4 is large, it is difficult for water to reach the space inside the bearing in the embodiment.

In the embodiment, the outer side lip 42 is formed so as not to be easily deformed (to have high rigidity). Specifically, the ratio T1 / L1 of the thickness T1 of the outer side lip 42 to the length L1 of the outer side lip 42 is that of the inner side lip 40 arranged on the outermost radial side among the inner side lips 38 and 40. It is larger than the ratio (T2 / L2) of the thickness T2 of the inner side lip 40 to the length L2. As described above, since the ratio T1 / L1 of the thickness T1 of the outer side lip 42 to the length L1 of the outer side lip 42 is large, the outer side lip 42 is not easily deformed. Therefore, even if a large water pressure is applied from the outside, it is difficult for water to pass between the outer side lip 42 and the second flange surface 4C, and the sealing device 20 has high protection performance from water to the sealing target. As used herein, the term "lip thickness" refers to the thickness of the central portion in the length direction of the lip. Therefore, when the lip is tapered as shown, the "lip thickness" is between the thickness of the tip and the thickness of the base.

On the other hand, the tightening allowance I1 for the second flange surface 4C of the outer side lip 42 is the tightening allowance I2 for the first flange surface 4B of the inner side lip 40 arranged on the outermost radial direction among the inner side lips 38 and 40. Smaller. Here, the tightening margin I1 of the outer side lip 42 is the position of the tip of the outer side lip 42 when the outer side lip 42 does not come into contact with the second flange surface 4C, and the outer side lip 42 is the second flange surface 4C. It is a difference in the direction of the central axis Ax of the hub bearing 1 at the position of the tip of the outer side lip 42 when it comes into contact with. The tightening margin I2 of the inner side lip 40 is the position of the tip of the inner side lip 40 when the inner side lip 40 does not contact the first flange surface 4B, and the inner side lip 40 comes into contact with the first flange surface 4B. It is a difference in the direction of the central axis Ax of the hub bearing 1 at the position of the tip of the inner side lip 40 at the time.

As described above, since the tightening allowance I1 of the outer side lip 42 with respect to the second flange surface 4C is small, the torque given to the hub 4 by the outer side lip 42 is small. Further, since the tightening allowance I1 is small, even if water passes between the outer side lip 42 and the second flange surface 4C, conversely, water is discharged through between the outer side lip 42 and the second flange surface 4C. Easy to do.

Further, when the inner side lips 38 and 40 and the outer side lips are not in contact with the hub 4, the tips of the inner side lips 40 and the outer side lips 42 arranged on the outermost radial side of the inner side lips 38 and 40 The distance D of the tip along the radial direction of the sealing device 20 is 4.5 mm or more. By sufficiently increasing the distance D in this way, even when the inner side lips 38 and 40 and the outer side lip 42 come into contact with the hub 4, the distance between the tip of the inner side lip 40 and the tip of the outer side lip 42 is large. Therefore, even if the outer water passes between the outer side lip 42 and the second flange surface 4C, the time until the water reaches the inner side lip 40 can be lengthened. However, in order to avoid an increase in the size of the device 20, the distance D is preferably 8.5 mm or less.

Further, since the distance D between the tips of the inner side lips 38 and 40 and the tips of the outer side lips 42 is large, the portion 46 between the inner side lips 40 and the outer side lips 42 is pushed to press the sealing device 20 to the outer ring of the hub bearing 1. It is easy to attach to 8. The portion 46 is an inner portion of the outer side lip 42 of the outer annulus portion 32 and overlaps the end surface of the end portion 8A of the outer ring 8. When the sealing device 20 is attached to the outer ring 8, the portion 46 is pushed to move the sealing device 20 along the central axis Ax. If the distance D is large, the portion 46 is wide, so that the work is easy.

FIG. 4 shows a sealing device of a comparative example. In this comparative example, the ratio T1 / L1 of the thickness T1 of the outer side lip 42 to the length L1 of the outer side lip 42 is that of the inner side lip 40 arranged on the outermost radial side among the inner side lips 38 and 40. It is smaller than the ratio (T2 / L2) of the thickness T2 of the inner side lip 40 to the length L2. As described above, since the ratio T1 / L1 of the thickness T1 of the outer side lip 42 to the length L1 of the outer side lip 42 is small, the outer side lip 42 is easily deformed. Therefore, when a large water pressure is applied from the outside, water easily passes between the outer side lip 42 and the second flange surface 4C.

In the comparative example, the tip of the outer side lip 42 comes into contact with the first flange surface 4B as well as the tip of the inner side lip 40, not with the second flange surface 4C.

In the comparative example, the distance D is smaller than 4.5 mm. Therefore, after the external water passes between the outer side lip 42 and the first flange surface 4B, the time until the water reaches the inner side lip 40 is short. Further, the outer side lip 42 overlaps the portion 48 of the outer annulus portion 32 that overlaps the end surface of the end portion 8A of the outer ring 8, and it is difficult to push this portion 48 to attach the sealing device 20 to the outer ring 8. be.

The embodiment can solve the problem of the comparative example.

FIG. 5 shows a sealing device 50 according to another embodiment of the present invention. The sealing device 50 has a different attachment method to the outer ring 8 from the above-described embodiment. Hereinafter, the difference between the embodiment of FIG. 2 and the embodiment of FIG. 5 will be described.

The sealing device 50 has a cylindrical portion 52, an annular portion 54, an inner annular portion 56, and lips 36, 38, 40, 42.

The end portion 8A of the outer ring 8 is fitted (that is, press-fitted) into the cylindrical portion 52 (mounting portion) by a tightening method. The cylindrical portion 52 is composed of a portion having a U-shaped cross section of the rigid ring 26, a portion of the elastic ring 24 embedded in the rigid portion, and a portion of the elastic ring 24 surrounding the rigid portion. The portion of the elastic ring 24 surrounding the rigid portion prevents the rigid ring 26 from being exposed to water.

The annular portion 54 extends radially inward from the cylindrical portion 52. The annular portion 54 is composed of a portion of the rigid ring 26 and a portion of the elastic ring 24. The portion of the rigid ring 26 comes into surface contact with the end surface of the end portion 8A of the outer ring 8.

The inner annular portion 56 extends radially inward from the annular portion 54. The inner ring portion 56 is composed of a portion of the rigid ring 26 and a portion of the elastic ring 24.

The grease lip 36 extends from the innermost edge of the inner annulus 56. The inner side lips 38 and 40 extend laterally (outboard side) and radially outward from the inner annulus 56. The outer side lip 42 extends laterally (outboard side) from the annular portion 54 and outward in the radial direction.

According to the sealing device 50 according to the embodiment, the tips of the inner side lips 38 and 40 come into contact with the first flange surface 4B of the hub 4, and the tips of the outer side lips 42 further contact the second flange surface 4C of the hub 4. Contact. Since the number of lips that come into contact with the hub 4 is large, it is difficult for water to reach the space inside the bearing in the embodiment.

The ratio T1 / L1 of the thickness T1 of the outer side lip 42 to the length L1 of the outer side lip 42 is the inner side of the inner side lips 38, 40 arranged on the outermost side in the radial direction with respect to the length L2 of the inner side lip 40. It is larger than the ratio of the thickness T2 of the side lip 40 (T2 / L2). As described above, since the ratio T1 / L1 of the thickness T1 of the outer side lip 42 to the length L1 of the outer side lip 42 is large, the outer side lip 42 is not easily deformed. Therefore, even if a large water pressure is applied from the outside, it is difficult for water to pass between the outer side lip 42 and the second flange surface 4C, and the sealing device 50 has high protection performance from water to the sealing target.

Since the tightening allowance I1 with respect to the second flange surface 4C of the outer side lip 42 is small, the torque given to the hub 4 by the outer side lip 42 is small. Further, since the tightening allowance I1 is small, even if water passes between the outer side lip 42 and the second flange surface 4C, conversely, water is discharged through between the outer side lip 42 and the second flange surface 4C. Easy to do.

Further, when the inner side lips 38 and 40 and the outer side lips are not in contact with the hub 4, the tips of the inner side lips 40 and the outer side lips 42 arranged on the outermost radial side of the inner side lips 38 and 40 The distance D of the tip along the radial direction of the sealing device 50 is 4.5 mm or more. By sufficiently increasing the distance D in this way, even when the inner side lips 38 and 40 and the outer side lip 42 come into contact with the hub 4, the distance between the tip of the inner side lip 40 and the tip of the outer side lip 42 is large. Therefore, even if the outer water passes between the outer side lip 42 and the second flange surface 4C, the time until the water reaches the inner side lip 40 can be lengthened. However, the distance D is preferably 8.5 mm or less in order to avoid increasing the size of the device 50.

Further, since the distance D between the tips of the inner side lips 38 and 40 and the tips of the outer side lips 42 is large, the portion 58 between the inner side lips 40 and the outer side lips 42 is pushed to press the sealing device 50 to the outer ring of the hub bearing 1. It is easy to attach to 8. The portion 58 is an inner portion of the outer side lip 42 of the annular portion 54 and overlaps the end surface of the end portion 8A of the outer ring 8. When the sealing device 50 is attached to the outer ring 8, the portion 58 is pushed to move the sealing device 50 along the central axis Ax. If the distance D is large, the portion 58 is wide, so that the work is easy.

Although the present invention has been illustrated and described above with reference to preferred embodiments of the present invention, those skilled in the art can change the form and details without departing from the scope of the invention described in the claims. It will be understood that there is. Such changes, modifications and modifications should be included within the scope of the invention.

In each of the above embodiments, the sealing device has two inner side lips 38, 40, but may have a single inner side lip.

Alternatively, three or more inner side lips may be provided. The ratio of the thickness T1 of the outer side lip 42 to the length L1 of the outer side lip 42. It is preferably larger than the ratio of the thickness of the inner side lips arranged on the outer side in the direction. The tightening allowance I1 of the outer side lip 42 with respect to the second flange surface 4C is smaller than the tightening allowance of the inner side lip arranged on the outermost radial side of the three or more inner side lips with respect to the first flange surface 4B. Is preferable. Sealing device for the tip of the inner side lip and the tip of the outer side lip 42, located on the outermost radial side of the three or more inner side lips, if the inner and outer side lips are not in contact with the hub 4. The distance along the radial direction is preferably in the range of 4.5 to 8.5 mm.

Aspects of the invention are also described in the numbered clauses below.

Clause 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.
The inner member has a cylindrical portion, a first flange surface arranged radially outside the cylindrical portion, and a second flange surface arranged radially outside the first flange surface. Cylinder,
The sealing device is
A mounting portion mounted on the outer member of the rolling bearing, and a mounting portion.
An inner annulus portion arranged radially inside from the mounting portion,
A grease lip formed of an elastic material extending from the inner ring portion toward the cylindrical portion of the inner member of the rolling bearing.
An inner side lip formed of an elastic material extending from the inner ring portion toward the first flange surface of the inner member of the rolling bearing.
It comprises an outer side lip formed of an elastic material extending from an outer position of the inner annulus towards the second flange surface of the inner member of the rolling bearing.
The inner side lip has a tip that slidably contacts the first flange surface.
The outer side lip has a tip that slidably contacts the second flange surface.
The ratio of the thickness of the outer side lip to the length of the outer side lip is larger than the ratio of the thickness of the inner side lip to the length of the inner side lip.
A sealing device characterized in that the tightening allowance of the outer side lip with respect to the second flange surface is smaller than the tightening allowance of the inner side lip with respect to the first flange surface.

Clause 2. When the inner side lip and the outer side lip are not in contact with the inner member, the distance between the tip of the inner side lip and the tip of the outer side lip along the radial direction of the sealing device is 4.5 mm or more. The sealing device according to Clause 1, characterized in that it is.

According to this clause, the distance between the tip of the inner side lip and the tip of the outer side lip is large, so even if the outer water passes between the outer side lip and the second flange surface, the water will reach the inner side lip. The time to reach can be lengthened. Further, since the distance between the tip of the inner side lip and the tip of the outer side lip is large, it is easy to push the portion between the inner side lip and the outer side lip to attach the sealing device to the outer member of the rolling bearing.

Clause 3. It comprises a plurality of inner side lips formed of an elastic material extending from the inner annulus towards the first flange surface of the inner member of the rolling bearing.
Each of the inner side lips has a tip that slidably contacts the first flange surface.
The ratio of the thickness of the outer side lip to the length of the outer side lip is the ratio of the thickness of the outermost inner side lip to the length of the innermost side lip arranged radially outer. Larger,
1. Sealing device.

Clause 4. When the inner side lip and the outer side lip are not in contact with the inner member, the tip of the inner side lip and the tip of the outer side lip arranged on the outermost radial side are along the radial direction of the sealing device. The sealing device according to Article 3, wherein the distance is 4.5 mm or more.

1 Hub bearing (rolling bearing)
2 holes 4 hubs (inner member)
4A Outer peripheral surface of the cylindrical part 4B First flange surface 4C Second flange surface 8 Outer ring (outer member)
8A End 20 Sealing device 28 Cylindrical part (mounting part)
36 Grease lip 38,40 Inner side lip 42 Outer side lip 50 Sealing device 52 Cylindrical part (mounting part)

Claims (4)

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.
The inner member has a cylindrical portion, a first flange surface arranged radially outside the cylindrical portion, and a second flange surface arranged radially outside the first flange surface. Cylinder,
The sealing device is
A mounting portion mounted on the outer member of the rolling bearing, and a mounting portion.
An inner annulus portion arranged radially inside from the mounting portion,
A grease lip formed of an elastic material extending from the inner ring portion toward the cylindrical portion of the inner member of the rolling bearing.
An inner side lip formed of an elastic material extending from the inner ring portion toward the first flange surface of the inner member of the rolling bearing.
It comprises an outer side lip formed of an elastic material extending from an outer position of the inner annulus towards the second flange surface of the inner member of the rolling bearing.
The inner side lip has a tip that slidably contacts the first flange surface.
The outer side lip has a tip that slidably contacts the second flange surface.
The ratio of the thickness of the outer side lip to the length of the outer side lip is larger than the ratio of the thickness of the inner side lip to the length of the inner side lip.
A sealing device characterized in that the tightening allowance of the outer side lip with respect to the second flange surface is smaller than the tightening allowance of the inner side lip with respect to the first flange surface. When the inner side lip and the outer side lip are not in contact with the inner member, the distance between the tip of the inner side lip and the tip of the outer side lip along the radial direction of the sealing device is 4.5 mm or more. The sealing device according to claim 1, wherein the sealing device is characterized by the above. It comprises a plurality of inner side lips formed of an elastic material extending from the inner annulus towards the first flange surface of the inner member of the rolling bearing.
Each of the inner side lips has a tip that slidably contacts the first flange surface.
The ratio of the thickness of the outer side lip to the length of the outer side lip is the ratio of the thickness of the outermost inner side lip to the length of the innermost side lip arranged radially outer. Larger,
The first aspect of claim 1, wherein the tightening allowance of the outer side lip with respect to the second flange surface is smaller than the tightening allowance of the inner side lip arranged on the outermost side in the radial direction with respect to the first flange surface. Sealing device. When the inner side lip and the outer side lip are not in contact with the inner member, the tip of the inner side lip and the tip of the outer side lip arranged on the outermost radial side are along the radial direction of the sealing device. The sealing device according to claim 3, wherein the distance is 4.5 mm or more.

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