JPH029145Y2 - - Google Patents

Description

[Detailed Description of the Invention] Purpose of the Invention (Field of Industrial Application) The present invention relates to a sealing structure for a sliding bush used in suspension arms of automobiles and the like.

(Prior Art) As shown in FIG. 4, an upper arm 51 constituting a suspension arm is formed with a branch arm 52 that is branched into two, and a tip of each branch arm 52 is inserted through the upper arm 51. A hole 53 is provided.

A shaft 54 for connecting to a body (not shown) is inserted into these insertion holes 53 via a bush 55, and after a retainer 61 is fitted to both ends of the shaft 54, It is screwed on.

As shown in FIG. 5, the conventional bushing 55 has a structure in which a back-up collar 58 is fixed to the inner circumferential surface of a cylindrical anti-vibration rubber material 57, and an outer cylinder 59 is fixed to the outer circumferential surface.

A synthetic resin insert 56 is provided between the bush 55 of this structure and the inner cylinder 63 on the shaft 54 in order to improve relative slidability in the circumferential direction.
is inserted.

Further, grease g is filled between the insert 56 and the shaft or bush in order to improve the slidability in the circumferential direction thereof. On the inner periphery of both ends of the backup collar 58,
An annular seal ring 60 whose outer circumferential surface is joined to the back-up collar 58 and whose inner circumferential edge is in contact with the shaft 54 is joined to seal the grease g between the shaft 54 and the bush 55 and to prevent foreign objects and Prevents water from entering.

The bush 55 having such a structure is the branch arm 5.
When assembled between the insertion hole 53 of No. 2 and the shaft 54, the slidability of the bush 55 in the circumferential direction is maintained well for a long period of time, but on the other hand, there are the following problems.

(Problems to be Solved by the Invention) In other words, if the surface pressure of the seal ring 60 against the shaft 54 is low, not only will the sealing performance deteriorate, but also foreign matter or water will easily enter between the shaft 54 and the bush 55 from the outside. .

In order to further improve the sealing performance of the seal ring 60, the seal ring 60 with respect to the shaft 54
If the surface pressure is increased, the grease g tends to break off between the shaft 54 and the seal ring 60.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a sliding bushing sealing mechanism that does not suffer from these problems.

Structure of the invention (Means for solving problems) In order to achieve the above-mentioned object, this invention includes a seal that protrudes from the seal ring and is pressed against the bush or shaft with a thick wall. an inner seal formed by a member; and an outer side formed by a protrusion that is formed integrally with the seal member, is thinner than the seal member, and is bent outward and pressed against the bush or shaft. The lubricant reservoir is formed between the two seal parts.

(Function) In the inner seal part on the inner side of the two seal parts formed on the outer periphery or the inner periphery of the seal ring, a thick seal member allows surface contact between the seal ring and the bush or shaft. A line contact is formed and leakage of lubricant or ingress of foreign objects etc. is prevented.

In the outer seal part on the outer side of the two seal parts, surface contact or line contact is formed between the seal ring and the bush or shaft by a thin protrusion, thereby preventing leakage of lubricant or intrusion of foreign objects, etc. .

Since a lubricant reservoir is formed between the two seal parts, lubricant accumulates in this lubricant reservoir.

Even if foreign matter should enter from the outer seal part, it will be prevented from entering the inner seal part and the lubricant film will be prevented from breaking.

(Example) Next, we will explain one embodiment of this invention.
As will be explained based on FIG. 3, the part to which this embodiment is applied is an insertion hole similar to the insertion hole of the conventional suspension arm shown in FIG.

As shown in FIG. 1, a flange 2 is welded and fixed on the outer periphery of a shaft 1, and a male thread 4 into which a nut 3 can be screwed is formed at the end of the shaft 1.

A cylindrical metal inner cylinder 5 is press-fitted into the shaft 1 from the male thread 4 side, and its end abuts against the side surface of the flange 2.

On the outer peripheral surface of the inner cylinder 5, from the flange 2 side, a hollow disc-shaped seal ring 6 and a polyacetal resin cylindrical insert 7 functioning as a sliding bearing are provided.
Seal rings 6 similar to those described above are successively fitted into the inner cylinder 5 so as to form concentric circles.

Note that although the inner cylinder 5 and the two seal rings 6 are in close contact, the inner cylinder 5 and the insert 7 are not in close contact with each other, and a slight clearance is formed between them.

A bush B configured as follows is fitted into the outer peripheral surface of the insert 7 so as to be concentric with the shaft 1.

That is, in the bush B, a cylindrical metal back-up collar 10 is joined to the inner peripheral surface of a cylindrical rubber member 9 made of anti-vibration rubber, and is supported on the inner surface of an insertion hole (not shown) of the upper arm. A cylindrical metal outer cylinder 11 is joined to the outer peripheral surface of the rubber member 9, and a washer-shaped metal back-up metal 12 whose periphery is bent is formed on two sides of the rubber member 9. They are joined with the curved ends facing outward.

A retainer 13 is placed against the seal ring 6 on the end side of the shaft 1, and a nut 3 is inserted from above.
is screwed down.

As shown in FIG. 2, the seal ring 6 is made of a metal hollow disk member 6a and a wear-resistant, set-resistant, and oil-resistant elastic material bonded to the outer peripheral surface of the hollow disk member 6a. For example, it is formed from a rubber seal member 6b.

Two seal parts that come into contact with the backup metal 12 are formed on the outer periphery _{of the seal member 6b, namely an inner seal part S 1 and an} outer seal part S ₂ . A lubricant reservoir 14 having a concave shape is formed.

In the inner seal portion _S1 , the circumferential surface of the seal ring 6 comes into line or surface contact with the inner surface of the back-up metal 12, similar to the seal portion in a conventional seal ring, so that a sealing action is exerted.

However, the outer seal portion _S2 is formed as follows.

As shown in FIG. 3, a protrusion 8 is formed on the outer circumferential surface of the seal member 6b near the outer side. The protrusion 8 extends outward in the radial direction and has a substantially lip-like cross-sectional shape and is thinner than the seal member 6b. ing.

When the seal ring 6 is attached to the side of the insert 7, the protrusion 8 is bent outward in the shaft axial direction, and both sides thereof become bend forming surfaces, and the bend on the insert 7 side is bent outward. The forming surface contacts the inner surface of the backup metal 12 to form an outer seal portion _S2 . And the protrusion 8
Metal 12 has increased resilience against bending.
It becomes a biasing force against Therefore, the lubricant G can be stored in the lubricant reservoir 14 by contacting the backup metal 12, and the sealing effect is further enhanced.

The seal structure employing the above configuration is assembled and formed in the following manner.

Press insert 7 into the inner peripheral surface of bush B,
Fill and apply lubricant G to its inner surface and both ends.
After that, the inner cylinder 5 is inserted, and the seal ring 6 is press-fitted into the inner cylinder 5 from both sides, and the bush B and the inner cylinder 5
An integrated object is assembled.

After this integral body is press-fitted between the insertion hole of the upper arm and the shaft 1 inserted into the insertion hole, the retainer 13 is applied to the end surface of the integral body.

Finally, when the nut 3 is screwed onto the male thread 4 of the shaft 1, the sealing structure of the sliding bush of this embodiment is formed.

This embodiment exhibits the following functions and effects.

When the bush B is twisted in the circumferential direction while the automobile is running, the insert 7 slides in the circumferential direction with respect to the inner cylinder 5. A room surrounded by the insert 7, the inner cylinder 5 and the two seal rings 6 contains lubricant G.
Since the insert 7 is filled with lubricant G, the slidability in the circumferential direction of the insert 7 in contact with the lubricant G is maintained well.

An inner seal portion S ₁ formed by contact between the seal ring 6 and the inner surface of the back-up metal 12
prevents the lubricant G filled in the chamber from leaking to the outside, and also prevents foreign matter, water, etc. from entering the chamber from the outside.

Since the inside of this inner seal portion _S1 is in contact with the lubricant G in the chamber, and the outside thereof is in contact with the lubricant G in the lubricant reservoir 14, film breakage of the inner seal portion _S1 is less likely to occur.

Since the lubricant reservoir 14 is formed in an annular shape on the circumferential surface of the seal member 6b of the seal ring 6,
The lubricant G filled therein performs a sealing action and backs up the sealing action of the inner seal portion _S1 .

In the outer seal portion _S2 , the thin protrusion 8 of the seal member 6b is urged against the inner surface of the back-up metal 12, so that the protrusion 8 follows the height change of the inner surface to make the surface pressure uniform. and contact the inner surface of the backup metal 12.

Therefore, the outer seal portion _S2 exhibits a sealing effect of preventing the lubricant G in the lubricant reservoir 14 from leaking to the outside, and a sealing effect of preventing foreign matter from entering the lubricant reservoir 14 from the outside. Furthermore, by forming the projection 8 with a thin wall, even if a force is applied to the projection 8, the projection 8 does not deform outward and the volume of the projection 8 itself does not change, so that the volume of the lubricant reservoir 14 is always kept constant. It is possible to reliably prevent this volume from becoming small and the film of the lubricant G to break, and to keep the surface pressure on the inner circumferential surface of the back-up metal 12 extremely small and uniform. As a result, wear resistance and durability can be significantly improved.

The present invention is not limited to the above embodiments, but
For example, it can be implemented in the following manner.

(1) The seal ring 6 can be joined to the backup metal 12 and a seal portion can be formed on the inner circumference of the seal ring 6. In this case as well, the same effects as in the embodiment described above are exhibited.

(2) Since the inner cylinder 5 is for press-fitting the bush B into the shaft 1, if the bush B can be attached to the shaft 1, the inner cylinder 5 can be omitted.

Therefore, the inner cylinder 5 after being press-fitted into the shaft 1
rotates or pivots together with the shaft 1, and has substantially the same function as the shaft 1 for the insert 7, so in this invention, the shaft 1 refers to the case where the inner cylinder 5 is provided and the case where it is not provided. shall mean both.

(3) A clearance can be formed between the insert 7 and the backup collar 10 without forming a clearance between the inner cylinder 5 and the insert 7.

(4) Grease is typically used as the lubricant G, but similar oils can also be used.

Effects of the Invention As detailed above, the present invention is such that the lubricant in the lubricant reservoir backs up the sealing action of the inner seal, and the outer seal absorbs the lubricant in the lubricant reservoir and, by extension, the lubricant from the inner seal. It seals to prevent lubricant from leaking to the outside and prevents foreign matter from entering the lubricant reservoir.Also, by making the protrusion that forms the outer seal part thin, the volume of the lubricant reservoir can be kept constant at all times. At the same time, it has the excellent effect of reducing surface pressure and significantly improving wear resistance and durability.
Therefore, in the seal mechanism of the present invention, the lubricant is retained between the bush and the shaft for a long period of time, and relative sliding in the circumferential direction between the two is performed smoothly. The riding comfort of an automobile or the like is maintained well.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of the embodiment, FIG. 2 is an enlarged view of the portion shown in FIG. FIG. 4 is an exploded perspective view of an upper arm to which the prior art is applied, and FIG. 5 is a longitudinal sectional view of the prior art. Shaft 1, insert 7, seal ring 6,
Seal member 6b, protrusion 8, lubricant reservoir 14, bush B, lubricant G, seal portions S ₁ and S ₂ .

Claims (1)

[Claims for Utility Model Registration] A synthetic resin insert 7 is inserted between the shaft 1 and the bush B, and a seal ring 6 for sealing a lubricant G between the shaft 1 and the bush B is located at both ends of the insert 7. In the seal structure of the sliding bush provided on the side, the seal ring 6 includes a thick seal member 6b that protrudes from the seal ring 6 and is pressed against the bush B or the shaft 1. Inner seal portion _S1 and this seal member 6b
The sealing member 6b is integrally formed with the sealing member 6b.
An outer seal part S2 is provided, which is formed by a protrusion 8 that is thinner than the above-described projection 8 and bent outward and pressed against the bush B or shaft ₁ , and between these two seal parts _S1 and _S2. A sliding bushing seal structure characterized in that a lubricant reservoir 14 is formed.