JP2002195418A - Sealing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sealing device having a structure rarely causing a problem in a caulking process at assembling and capable of stably sealing and fixing a fit section. SOLUTION: A step section 2b is formed on the atmosphere side O on the outer peripheral end face of a metal ring 2 to form a closed space together with the end section 204a of an outer tube 204 bent to the inner side and pressed to the atmosphere side O of the metal ring 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sealing device which is fitted and fixed inside a tubular member by an end of the tubular member which is bent inward, and securely seals the sealing device with the tubular member. Related to technology.

[0002]

2. Description of the Related Art As a conventional sealing device of this type, there is, for example, a reciprocating sealing device 100 provided at a shaft sealing portion of a gas-filled type hydraulic shock absorber 200 shown in FIG.

The hydraulic shock absorber 200 includes a rod 201 reciprocating in an inner cylinder 203, a piston 202 provided on the rod 201, a sealed fluid L200 above and below the piston 202, and a valve 202a provided on the piston 202. This generates a damping force in the reciprocating stroke of the rod 201.

[0004] An outer cylinder 204 constituting a reservoir chamber 207 is disposed outside the inner cylinder 203, and the gas chamber G200 and a part of the sealed fluid L200 are sealed in the reservoir chamber 207. A communication passage 208 connecting the reservoir chamber 207 and the piston lower chamber 206 is provided at a lower end of the communication path 208.

Reference numeral 102 denotes a rod guide, which is a communication passage 10 for returning the sealed fluid L200 and gas G200 flowing out of the upper piston chamber 205 through the clearance 209 between the rod 201 and the rod guide 102 to the reservoir chamber 207.
3 are provided.

On the other hand, the sealing device 100 is mounted on the above-described hydraulic shock absorber 200 and includes a seal portion 101 for sealing the sliding surface of the rod 201. The swage is fixed.

FIG. 4A is an enlarged sectional view of a main part for explaining the sealing device 100. As shown in FIG.

The sealing device 100 includes a main lip 101a made of a rubber-like elastic body and a dust lip 101 at its inner diameter.
b is provided.

Reference numeral 100a denotes a metal ring, and an annular fitting lip portion 100 made of the same rubber-like elastic material as the seal portion 101 fitted on the inner diameter side of the outer cylinder 204 on the sealing side of the outer diameter portion.
b is provided so as to protrude outside the end 100c of the metal ring 100a.

FIG. 4B is a view for explaining a caulking process performed when the sealing device 100 is fixed to the shaft sealing portion of the hydraulic shock absorber 200.

In the caulking process, the sealing device 100 is
4, the end 204a of the outer cylinder 204 is bent in the direction of arrow C by pressing against an unillustrated caulking jig while rotating relative thereto. And metal ring 1
00a is given a compressive force in the axial direction (arrow D) to seal and fix.

[0012]

However, in the case of the prior art as described above, the sealing device 100 moves during the caulking process, or the opposite side of the sealing device 100 with which the caulking jig comes into contact is once inclined. Phenomenon such as lifting up or returning to the original position.

Although this is considered to be a problem in the working method of the caulking process, as in the sealing device 100 of FIG. 4A, the lip portion 100 is fitted to the outer peripheral end surface of the end portion 100c.
If there is a thin rubber surrounding part 100d following b,
There is a possibility that the rubber surrounding portion 100d may be moved or compressed during the caulking process and may be damaged.

In order to solve this problem, the present applicant has proposed a sealing device 150 shown in FIG. 5, which will be described below.

As shown in FIG. 5, the sealing device 150 is in contact with a main lip 153 made of a rubber-like elastic material, a dust lip 154, and a rod guide (not shown) on the inner diameter of a flat washer-shaped metal ring 152 so as to be reversed. A seal 151 having a lip 155 functioning as a stop valve is provided. The main lip 153 is urged inward by a spring ring 156 in order to apply a tightening force when abutting on the surface of a rod (not shown).

A chamfered portion 152b having an R-shaped cross section depressed inward is provided at a corner on the sealing side M of the outer peripheral end surface 152a of the metal ring 152. Further, the corner 152c on the sealing side M of the chamfered portion 152b has a round shape (having a round shape on the outside).

On the sealing side M of the outer diameter portion of the metal ring 152, an annular fitting seal portion 157 made of the same rubber-like elastic material as the seal portion S is integrally provided. The fitting seal portion 157 projects outward from the outer peripheral end surface 152a of the metal ring 152, abuts against the inner peripheral surface of a tubular member (not shown, such as the outer cylinder 204 in FIG. 3), and forms the metallic ring 152 and the cylindrical member. The gap between the members can be sealed.

The outer edge 157a of the fitting surface of the fitting seal portion 157 with the metal ring 152 is formed into a chamfered portion 152.
b, and the rubber is not generated on the outer diameter side (upper side in the figure).

The caulking process is the same as the process shown in FIG. 4 described above. However, since no rubber is generated on the outer peripheral end surface 152a, the sealing device 150 is moved or the sealing device 150 is moved.
Even when the opposite side of the caulking jig floats up and returns to its original position, the surroundings of the rubber and the fitting seal portion 157 do not occur at all.

The rounded chamfered portion 1
The corner portion 152c of the sealing side M of the sealing member 52b prevents cracking and peeling inside the fitting seal portion 157 that has been bent and deformed.

However, such a sealing device 150
In this case, it is difficult to deal with the equipment because the production equipment is special, and the production capacity is limited.

If the rubber stopper of the fitting seal 157, that is, the chamfered part 152b of the metal ring 152 or the part of the mold on which the rubber is stopped is slightly damaged, the rubber may leak.

The present invention has been made to solve the above-mentioned problems of the prior art, and an object of the present invention is to provide a structure which does not easily cause a problem in a caulking step at the time of assembling. An object of the present invention is to provide a sealing device capable of performing stable sealing and fixing.

[0024]

In order to achieve the above object, according to the present invention, there is provided a reinforcing ring which is fitted inside a cylindrical member, and which is disposed at an inner diameter portion of the reinforcing ring and has a cylindrical shape. A sealing portion that is in sliding contact with a shaft inserted into the member, and protrudes outward from an outer peripheral end surface of the reinforcing ring on a sealing side of an outer diameter portion of the reinforcing ring, and abuts on an inner peripheral surface of the tubular member. And a fitting seal portion for sealing a gap between the reinforcing ring and the cylindrical member. The cylindrical member is bent inward by pressing an end of the cylindrical member bent inward against a non-sealing side of the reinforcing ring. In a sealing device fixed to a member, a closed space is formed on an anti-sealing side of an outer peripheral end surface of the reinforcing ring together with an end of the cylindrical member that is bent inward and pressed against the anti-sealing side of the reinforcing ring. A space forming part is provided.

According to this configuration, in the caulking process at the time of assembling, even if the rubber surrounding portion is moved or compressed during the caulking process and is damaged, rubber burrs caused by the damage can be stored in the closed space. Rubber burrs can be prevented from being released to the non-sealing side.

It is also preferable that the closed space forming portion is a step portion provided at a corner on the non-sealing side of the outer peripheral end surface of the reinforcing ring.

[0027]

Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. However, the dimensions of the components described in this embodiment,
The material, shape, and relative arrangement thereof should be appropriately changed depending on the configuration of the apparatus to which the invention is applied and various conditions, and are not intended to limit the scope of the invention to the following embodiments. Note that the same components as those described in the section of the related art are denoted by the same reference numerals, and description thereof will be omitted.

FIG. 1 is a cross-sectional configuration explanatory view for explaining an embodiment of a sealing device 1 to which the present invention is applied.

The sealing device 1 is fixed to, for example, a shaft sealing portion of a gas-sealed hydraulic shock absorber, and is used as a sealing fluid sealed inside the hydraulic shock absorber, similarly to the sealing device described in the section of the prior art. The oil or gas is sealed so as not to leak from the gap on the surface of the rod as the reciprocating shaft.

The configuration of the hydraulic shock absorber can be the same as that of the hydraulic shock absorber 200 shown in FIG. 3, and for the outline, refer to FIG. 3 and the description of the prior art. It can be grasped.

The sealing device 1 includes a seal portion S having a main lip 3 made of a rubber-like elastic body and a dust lip 4 on the inner diameter portion of a flat washer-shaped metal ring 2 as a reinforcing ring.

The main lip 3 has a two-stage lip and is formed with a screw which exerts a pump effect. Thereby, the behavior of the lip is stabilized, and the sealing property is improved. As the screw, a screw groove, a screw thread, a slit shape or the like can be selected and adopted according to the purpose of use. The main lip 3 is urged in the inner diameter direction by a spring ring 5 that supplements a tension force when the main lip 3 comes into contact with the surface of a rod (not shown). The dust lip 4 is also urged in the inner diameter direction by a spring ring 6 that supplements the tension force.

Further, the sealing side M of the outer peripheral end face 2a of the metal ring 2
Has a round shape (having a round shape on the outside).

On the sealing side M of the outer diameter portion of the metal ring 2, an annular fitting seal portion 7 made of the same rubber-like elastic material as the seal portion S is integrally provided.

The fitting seal portion 7 protrudes outward from the outer peripheral end surface 2a of the metal ring 2 and contacts the inner peripheral surface of a tubular member (not shown) (such as the outer cylinder 204 in FIG. 3) to form a metal. The gap between the ring 2 and the cylindrical member can be sealed.

An annular step 2b is provided at a corner of the outer peripheral end surface 2a of the metal ring 2 on the atmosphere side O.

The step portion 2b forms a closed space as a closed space forming portion together with the end portion 204a of the outer cylinder 204 as a crimped cylindrical member in a crimping step described later.

FIG. 2 is a view for explaining a caulking step performed when the sealing device 1 is fixed to the shaft sealing portion of the hydraulic shock absorber. In the figure, reference numeral 204 denotes an outer cylinder, and 204a denotes an end of the outer cylinder 204.

In the caulking step, after the sealing device 1 is assembled inside the outer cylinder 204, the end portion 204a of the outer cylinder 204 is pressed against the caulking jig (not shown) while rotating relatively to bend in the direction of arrow A. Then, an axial compressive force (arrow B) is applied to the metal ring 2 to seal and fix.

At this time, the end 204a of the outer cylinder 204 is in pressure contact with the atmosphere side O end face 2d of the metal ring 2, and is closed together with the stepped portion 2b provided on the atmosphere side O of the outer circumference end face 2a of the metal ring 2. A space 8 is formed.

When such a caulking process is performed, the sealing device 1 moves during the caulking process, or the sealing device 1 comes into contact with the caulking jig, such that the sealing device 1 is lifted so as to be inclined once and returned to the original position. Symptoms may occur.

When such a phenomenon occurs, in the sealing device 1, if a thin rubber wrap 7a following the seal portion 7 is fitted on the outer peripheral end surface 2a, the rubber wrap 7a may be removed during the caulking process. Can be moved or compressed and damaged.

However, in this embodiment, a step 2b is provided on the atmosphere side O of the outer peripheral end face 2a of the metal ring 2,
Further, the closed space 8 is formed by the step portion 2b and the end portion 204a of the outer cylinder 204, so that the rubber surrounding portion 7a
Even if is moved or compressed during the caulking process and is damaged,
Before the rubber burrs come out to the atmosphere side O during the caulking process, rubber burrs can be accumulated in the stepped portion 2b, and after the caulking process, the rubber burrs can be accumulated in the closed space 8, so that the rubber burrs are accumulated on the atmosphere side O. It is possible to prevent release.

Therefore, the sealing device 1 is
It is possible to prevent the contamination after being incorporated into 0.

Here, the step 2b provided on the metal ring 2
May be appropriately set in accordance with the amount of rubber in the rubber circling portion 7a. Further, if a closed space is formed with the end portion 204a of the outer cylinder 204, the size of the step portion as in the present embodiment may be reduced. The present invention is not limited to this, and may be a stepped portion or a concave portion.

The outer peripheral end surface 2a of the metal ring 2 has a sealing side M
Since the corner portion 2c has a round shape, it is possible to prevent cracks and peeling from occurring inside the fitting seal portion 7 that has been bent and deformed, and to prevent the sealing performance of the fitting seal portion 7 from deteriorating. And reliability and durability can be improved.

[0047]

As described above, according to the present invention,
Rubber burrs generated by the caulking process during assembly can be prevented from being released to the non-sealing side, improving assemblability and sealing performance, reliability, quality and durability at the fitting part of the sealing device. Can be improved.

[Brief description of the drawings]

FIG. 1 is a cross-sectional configuration explanatory view of a sealing device according to an embodiment of the present invention.

FIG. 2 is a view for explaining a caulking step of the sealing device.

FIG. 3 is a diagram of a conventional gas-filled type hydraulic shock absorber.

FIG. 4 is a view showing a conventional sealing device.

FIG. 5 is a view showing a conventional sealing device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Sealing device 2 Metal ring (reinforcement ring) 2a Outer peripheral end surface 2b Step part 2c Corner part 2d End surface 3 Main lip 4 Dustrip 5,6 Spring ring 7 Fitting seal part 7a Rubber surrounding part 7a 8 Closed space 200 Hydraulic shock absorber M Sealed side O Atmospheric side S Seal part

Claims (2)

[Claims] 1. A reinforcing ring fitted inside a cylindrical member, a seal portion disposed on an inner diameter portion of the reinforcing ring and slidably in contact with a shaft inserted through the cylindrical member, and an outer portion of the reinforcing ring. On the sealing side of the diameter portion, a fitting seal portion that projects beyond the outer peripheral end surface of the reinforcing ring and abuts against the inner peripheral surface of the cylindrical member to seal a gap between the reinforcing ring and the cylindrical member. A sealing device fixed to the cylindrical member by pressing an end of the cylindrical member bent inward against the non-sealing side of the reinforcing ring; anti-sealing of an outer peripheral end surface of the reinforcing ring. A sealing device, comprising: a closed space forming part which is bent inward and forms a closed space together with an end of the cylindrical member which is pressed against the non-sealing side of the reinforcing ring. 2. The sealing device according to claim 1, wherein the closed space forming portion is a step portion provided at a corner of the outer peripheral end surface of the reinforcing ring on a side opposite to the sealing side.