JPH088343Y2 - Bearing sealing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention mainly relates to a sealing device used for a bearing of a hub unit of an automobile.

<Prior Art> FIG. 2 shows a conventional sealing device used for a bearing of an automobile hub unit.

As shown in the figure, the conventional sealing device has a first ring body 21.
And a second ring body 22 and a seal member 23.

Each of the first ring body 21 and the second ring body 22 is formed of an annular plate having a substantially L-shaped cross section. The L-shaped inner surfaces of both ring bodies 21 and 22 face each other, and the first ring body 21 is the outer ring 24 of the bearing.
The second ring 22 is attached to the inner ring 25 of the bearing. The seal member 23 is baked and attached to the leading edge of the disc portion by using the first ring body 21 on the outer ring 24 side as a core metal.
The seal member 23 includes a pair of radial lips 23a, 23b that come into contact with the cylindrical surface of the L-shaped inner surface of the second annular body 22.
And a side lip 23c that contacts the disk surface. The second ring body 22 is located outside the first ring body 21 in the axial direction, and a labyrinth L is formed between the leading edge of the disc portion and the cylindrical portion of the first ring body 21. .

<Problems to be Solved by the Invention> A sealing device having the above-described configuration is provided with a labyrinth L and a sealing member.
The sliding contact of 23 prevents the intrusion of muddy water from the outside and the leakage of grease from the inside. There is a demand for this, and in view of the required performance, the conventional one has a problem in sealing performance.

First, in this type of sealing device, the space between the ring bodies 21 and 22 serves as a path for entering muddy water and serves as a path for leaking out grease or the like, but in the conventional case, this path is relatively short,
Intrusion and leakage are likely to occur.

Further, in the conventional sealing device, since the single sealing member 23 is used for sealing, it is easily affected by the pressure difference between the inside and the outside,
When the pressure difference between the inside and the outside is very large, the so-called “breathing phenomenon” of the seal member 23 causes the grease held by the lips 23a, 23b, 23c to be extruded or muddy water to be sucked in.

On the other hand, it is conceivable to lengthen the path formed between the annular members and increase the number of lips of the seal member, but simply lengthen the path or increase the number of lips. Only by increasing the number, the axial width of the entire sealing device becomes wide, which hinders mounting on the bearing.

The present invention has been made in view of the above problems, and an object of the present invention is to improve the sealing performance without increasing the axial width.

<Means for Solving the Problems> In order to achieve the above object, the present invention comprises first to third ring bodies and first and second seal members, and first and second ring members are provided. The two annular bodies have a substantially L-shaped cross section, and are attached to one raceway ring and the other raceway ring so that their L-shaped inner surfaces face each other, and the first and second seal members are respectively the first and second seal rings. And the second ring body is attached to the leading edge of the disc portion and contacts the other ring body, and the third ring body is positioned alternately with respect to the first and second ring bodies. So as to be attached to the bearing ring on the mounting side of the first ring body on the axially outer side of these ring bodies,
The bearing sealing device is configured to form a labyrinth between the ring body and the bearing ring on the mounting side.

<Operation> In the above-described configuration, first, the labyrinth on the outer diameter side of the third ring body prevents the entry of muddy water.

In addition, the first to third annular bodies are positioned in a disjoint relationship with each other along the axial direction, and a long meandering path is formed between them, so that the path prevents the intrusion of muddy water and the leakage of grease. Less likely to happen.

Further, since there are two seal members and the contact seals are formed at positions separated from each other, the space between the seal members acts as a pressure buffer, and the influence of the pressure difference between the inside and outside of the bearing is reduced.

Here, as compared with the length of the path between the ring bodies, the occupied width of the whole ring body is narrow, and each sealing member is mainly composed of a radial lip, and does not take a large space in the axial direction. The axial width of the entire device becomes narrow.

<Embodiment> Hereinafter, the present invention will be described in detail based on an embodiment shown in the drawings.

FIG. 1 is a sectional view of a sealing device according to an embodiment of the present invention, in which reference numeral 1 is an inner ring of a bearing, 2 is an outer ring of the bearing, and 3 is a ball.

The sealing device of this embodiment has a first bearing in order from the inside.
It has three ring bodies, a ring body 4, a second ring body 5, and a third ring body 6.

Of these, both the first and second ring bodies 4 and 5 serve as a core metal of the seal member, and have substantially L-shaped cross-sectional shapes, and the cylindrical portions 4a and 5a and the disc portion, respectively. It consists of 4b and 5b. The first ring body 4 is fitted to the inner ring 1 and the second ring body 5 is fitted to the outer ring 2 in such a manner that the L-shaped inner surfaces of both ring bodies 4 and 5 face each other.

First and second seal members 7 and 8 are attached to the first and second ring bodies 4 and 5 by baking. That is, the first seal member 7 is attached to the outer peripheral edge of the disc portion 4b of the first ring member 4.
A forked radial lip 7a, 7b that contacts the second ring-shaped cylindrical portion 5a is formed on the. In addition, the disk portion 5 of the second ring body 5
A second seal member 8 is attached to the inner peripheral edge of b, and the second seal member 8 is formed with bifurcated radial lips 8a and 8b that come into contact with the first annular body portion 4a.

The third ring body 6 is a slinger having a U-shaped cross section,
The labyrinth L is formed between the outer ring 2 and the outer ring 2 and is attached to the inner ring 1 on the axially outer side of the ring body 5 with the U-shaped inner surface facing outward.

In this way, the third ring body 6 is attached to the axially outer position of the inner ring 1, so that the first ring body 4, the second ring body 5, and the third ring body
The ring body 6 is juxtaposed in the axial direction in a gap-like manner, and a meandering path is formed between these ring bodies 4, 5, 6.

In the above structure, first, the labyrinth L between the outer diameter portion of the third ring body 6 and the outer ring 2 prevents the intrusion of muddy water. Further, even if the muddy water enters the inside of the third ring body 6, the muddy water that has invaded is accompanied by the labyrinth L as the inner ring 1 rotates.
Emitted from.

Further, since a long meandering path is formed between the first to third ring bodies 4, 5 and 6, this path makes it difficult for intrusion of muddy water and leakage of grease.

Further, since the first and second seal members 7 and 8 form a contact seal at positions separated from each other, there is a relatively large space between the seal members 7 and 8, and this space is inside and outside the bearing. It acts as a buffer against the pressure difference, and the influence of the pressure difference is reduced. That is, even if the pressure difference between the inside and outside of the bearing is large,
The space between both seal members 7 and 8 absorbs the pressure difference between the inside and outside, and as in the case of a single seal member, the grease may be pushed out or muddy water may be sucked in due to the "breathing phenomenon". Absent.

Further, since both seal members 7 and 8 are in contact with each other in opposite directions, even if the sealing performance of one seal member 8 (7) deteriorates as the inner ring 1 rotates, the other seal member 7 The sealing performance of (8) is improved and complements each other, and as a whole, a constant sealing performance independent of the rotation speed is obtained.

In the illustrated embodiment, each seal member 7, 8 is provided with only a radial lip, but one or both seal members 7, 8 are in contact with the disk portions 5b, 4b of the other ring members 5, 4. You may provide the side lip.

<Effect of the Invention> As described above, according to the present invention, the labyrinth on the outer diameter side of the third ring body, the meandering long path formed between the three ring bodies, and the two seals. The sliding contact of the members can surely prevent intrusion of muddy water and leakage of grease, and high sealing performance can be obtained.

In this case, since the ring bodies are arranged in a distorted shape, the axial width of the whole ring body is narrower than the length of the path between the ring bodies,
Further, since each seal member is mainly composed of a radial lip and does not take up a large space in the axial direction, the axial width of the entire device does not become wide, and it can be mounted in the narrow space similar to the conventional one. .

[Brief description of drawings]

FIG. 1 is a sectional view of a bearing sealing device according to an embodiment of the present invention, and FIG. 2 is a sectional view of a conventional example. 1 ... Inner ring, 2 ... Outer ring, 4 ... First ring body, 5 ... Second ring body, 6
... 3rd annular body, 7 ... 1st sealing member, 8 ... 2nd sealing member.

Claims (1)

[Scope of utility model registration request] 1. A first to a third ring body, and first and second ring bodies.
The first and second annuluses each have a substantially L-shaped cross section.
The die inner surfaces are attached to one raceway and the other raceway so as to face each other, and the first and second sealing members are respectively attached to the leading edges of the disc portions of the first and second annular bodies. Mounted on and in contact with the other annulus, the third annulus being axially outside the first annulus such that it is staggered relative to the first and second annulus. The bearing sealing device is attached to a ring on the mounting side of the ring body, and forms a labyrinth with the ring on the mounting side of the second ring body.