JP4465739B2 - Sealing device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a sealing device used for, for example, a shaft seal portion of various devices.
[0002]
[Prior art]
Conventionally, as this type of sealing device, for example, there is a device as shown in FIG. As shown in FIG. 5, the sealing device 100 is roughly divided into a rubber-like elastic seal portion 102, a fixing portion 104 fixed to the housing 115, and a bellows portion 103 interposed between the two portions. Is composed of.
[0003]
Furthermore, the seal part 102 is configured by a seal lip 102A that contacts the shaft 111 and seals oil or the like on the sealing target side S, and a bumper part 102B.
[0004]
If the shaft 111 is not eccentric at all and does not swing, the bumper portion 102B is sealed by the seal lip 102A without contacting the shaft 111.
[0005]
On the other hand, during the eccentric and swing motion of the shaft 111, the bumper portion 102B receives a force directly from the shaft 111, transmits the force to the bellows portion 103, and the bellows portion 103 bends so that most of the shaft 111 is bent. It is configured to absorb displacement.
[0006]
That is, the bumper portion 102B is for transmitting the force due to the inclination of the shaft 111 to the bellows portion 103 so that the contact state of the seal lip 102A with the shaft 111 does not change when the shaft 111 is inclined.
[0007]
As a result, the relative positional relationship of the shaft 111 as viewed from the seal portion 102 is mainly a swing motion around the bumper portion 102B other than the portion absorbed by the bellows portion 103 as described above. Also in this case, the seal lip 102A follows the shaft 111 and can cope with a relatively large eccentric motion or swing motion.
[0008]
[Problems to be solved by the invention]
However, in the case of the prior art as described above, the seal portion 102 is generally integrally molded from rubber, and the bumper portion 102B is made of rubber having relatively low rigidity like the other seal lips 102A. Therefore, at the time of high eccentricity, the seal lip 102A could not follow the shaft 111, and the sealing performance was deteriorated.
[0009]
In other words, when the eccentricity is high, the contact portion in the circumferential direction of the bumper portion 102B that is strongly in contact with the shaft 111 is deformed, so that the portion of the bumper portion 102B opposite to the deforming contact portion in the circumferential direction is deformed. This is because a gap is formed between the shaft 111 and the seal lip 102A supported by the bumper portion 102B as a root and the shaft 111 without being able to follow the eccentricity.
[0010]
The present invention has been made in order to solve the above-described problems of the prior art. The object of the present invention is to improve the sealing performance of the seal lip by suppressing the deformation of the bumper portion when it is eccentric. To provide an apparatus.
[0011]
[Means for Solving the Problems]
In order to achieve the above object, the present invention seals an annular gap between two members which are assembled concentrically and relatively movable together, and is fixed to one of the two members. A fixed portion, a seal portion that slidably seals with the other member of the two members, and a seal portion that is provided between the seal portion and the fixed portion, and causes the seal portion to follow the eccentricity of the other member. A sealing lip made of a rubber-like elastic body that is slidably in sealing contact with the other member, and continuously provided on the atmosphere side of the sealing lip, the sealing device and a bumper part is made of a rubber-like elastic body to convey the force received by the eccentric of the other member in the bellows portion, said bumper portion reinforces the bumper portion, the ring is provided with a rigid The phosphorus It is characterized by having a fitting portion to be fitted on the outer peripheral surface of the bumper portion, and a suppressing dust lip of the dust from the atmosphere side to thereby reach the sealing lip.
[0012]
Therefore, since the bumper portion can be reinforced and strengthened, the deformation of the bumper portion can be suppressed even when the eccentricity is high, and as a result, the sealing lip can be prevented from becoming intimate and the sealing performance can be improved. .
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Exemplary embodiments of the present invention will be described in detail below with reference to the drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the components described in this embodiment are not intended to limit the scope of the present invention only to those unless otherwise specified. Absent.
[0016]
( Reference Example ) FIG. 1 is a view showing a sealing device according to a reference example .
[0017]
In FIG. 1, a sealing device 1 seals an annular gap between a housing 15 as two members assembled so as to be relatively movable with each other and a shaft 11 inserted into the housing 15 at a shaft sealing portion as in the prior art. To do.
[0018]
The sealing device 1 generally includes a seal portion 2 having a seal lip 2A in sealing contact with the shaft 11, a fixing portion 4 fitted and fixed to the inner periphery of the housing 15, and a wave shape interposed between the two portions. The bellows part 3 is provided.
[0019]
The fixing portion 4 includes a reinforcing ring 7 that prevents deformation of the fixing portion 4, and a rubber-like elastic body 6 that is integrally baked and fixed to the reinforcing ring 7.
[0020]
The reinforcing ring 7 is a cylindrical member having a cylindrical portion 71 and an inward flange portion 72 extending in the inner diameter direction at the atmosphere side A end portion of the cylindrical portion 71. The rubber-like elastic body 6 is integrally baked and fixed continuously to the atmosphere side A end surface of the inward flange portion 72 of the reinforcing ring 7, the outer peripheral surface of the cylindrical portion 71, and the sealing target side S end surface.
[0021]
In the fixing portion 4, the cylindrical portion 71 of the reinforcing ring 7 is fitted and fixed to the inner peripheral surface of the housing 2 via the rubber-like elastic body 6.
[0022]
On the other hand, a bellows portion 3 made of a rubber-like elastic body is provided at the inner end of the inward flange portion 72 of the reinforcing ring 7, and a seal portion 2 is provided at the inner end of the bellows portion 3.
[0023]
When the shaft 11 is decentered or swung, the bellows portion 3 is directly transmitted with the tilting force of the shaft 11 from the bumper portion 2B of the seal portion 2, and most of the shaft 11 is bent by the force. The displacement is absorbed and the relative displacement relationship with respect to the shape of the seal portion 2 and the shaft 11 is maintained.
[0024]
The seal portion 2 has a rubber-like elastic seal lip 2A that is in slidable sealing contact with the outer peripheral surface of the shaft 11, and a rubber-like rubber having a substantially rectangular cross section provided continuously on the atmosphere side A of the seal lip 2A. And a bumper portion 2B made of an elastic body.
[0025]
The seal lip 2 </ b> A extends along the outer peripheral surface of the shaft 11 to the sealing target side S, has a wedge-shaped cross section, and has a sliding surface in which the lip end portion is slidably in sealing contact with the outer peripheral surface of the shaft 11. Form. And the oil etc. of the sealing object side S are sealed and the leak to the atmosphere side A is prevented.
[0026]
A garter spring 8 is provided on the outer peripheral side of the seal lip 2A. The garter spring 8 applies a pressing force to the shaft 11 at the lip end of the seal lip 2A.
[0027]
The bumper part 2B receives the tilting force of the shaft 11 by the bumper part 2B and transmits the force directly to the bellows part 3 when the shaft 11 is eccentric or swung. As a result, when the shaft 11 is inclined, a large biased force is not applied to the seal lip 2A, and the shaft 11 is always contacted with substantially the same contact force, and the contact state of the seal lip 2A with the shaft 11 does not change. I am doing so.
[0028]
Here, an annular groove 8 is provided on the outer peripheral surface of the bumper portion 2B, and a ring 9 as a reinforcing means is fitted into the annular groove 8.
[0029]
The ring 9 is an annular ring made of a material having rigidity such as metal or resin, and the bumper portion 2B is designed to suppress deformation of the rubber-like elastic body caused by a force caused by the inclination of the shaft 11 at the time of high eccentricity. Reinforced and reinforced to increase rigidity.
[0030]
Therefore, in the sealing device 1 having the above configuration, the bumper portion 2B can be reinforced and strengthened by the rigid ring 9 into which the bumper portion 2B is fitted, and even when the shaft 11 is highly eccentric, deformation of the bumper portion 2B can be suppressed. It is possible to improve the sealing performance by preventing the seal lip 2A from coming into close contact.
[0031]
That is, since the bumper portion 2B is strengthened when the shaft 11 is highly eccentric, the shaft 11 swings around the bumper portion 2B, and there is no gap between the shaft 11 and the bumper portion 2B. The followability of the shaft 11 of the seal lip 2A having 2B as a base is improved, and the sealing performance is also improved. Further, since the ring 9 is configured to be fitted into the annular groove 8 on the outer peripheral surface of the bumper portion 2B, the sealing device 1 is first integrally formed with a rubber-like elastic body, and then the ring 9 manufactured separately is attached to the annular groove. 8 and can be easily attached.
[0032]
In addition, as above-mentioned, the ring 9 should just enter with the rigidity which strengthens the bumper part 2B, and a material is not restricted to a metal or resin. Not only the material but also the method of attaching the ring 9 is not only a method of fitting in the annular groove 8, but also, for example, by a method such as integral molding with a rubber-like elastic body, baking or bonding to the bumper part 2B, etc. It can also be installed.
[0033]
Moreover, even if the ring 9 is partly cut and becomes an annular shape after mounting, the same effect as in the present reference example can be obtained.
[0034]
To (an embodiment of the present invention) FIGS. 3 and 4, a configuration in which dust lip 9c is provided in the ring 9 having a rigid below. Here, only the ring 9 which is a characteristic part will be described, and the other configurations are the same as those in the above-described reference example, and thus the same reference numerals are given and description thereof is omitted.
[0035]
As shown in FIGS. 3 and 4 , the ring 9 of the present embodiment includes a ring body 9a that is annular on the atmosphere side A of the bumper portion 2B, and an outer peripheral surface of the bumper portion 2B from the ring body 9a. And a plurality of fitting portions 9b to be fitted, and a dust lip 9c provided at the inner end of the ring body 9a.
[0036]
Even if it does in this way, the effect similar to a reference example can be acquired. Moreover, it is possible to exhibit better sealing performance without causing dust to reach the seal lip 2A .
[0037]
【The invention's effect】
As described above, according to the present invention, the bumper portion is provided with a rigid ring that reinforces the bumper portion. It is possible to prevent the loss and improve the sealing performance. Further, dust can be prevented from reaching the seal lip by the dust lip provided on the ring.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a sealing device according to a reference example .
FIG. 2 is an explanatory view showing a ring according to a reference example .
3 is a cross-sectional view showing a sealing device according to an embodiment of the present invention.
4 is an explanatory view showing a ring according to an embodiment of the present invention.
FIG. 5 is a cross-sectional view showing a conventional sealing device.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Sealing device 2 Seal part 2A Seal lip 2B Bumper part 3 Bellow part 4 Fixing part 6 Rubber-like elastic body 7 Reinforcement ring 71 Cylindrical part 72 Inward flange part 8 Garter spring 9 Ring (reinforcing means)
9a Ring body 9b Insertion part 9c Dustrip 11 Shaft 15 Housing

Claims (1)

It seals the annular gap between two members that are assembled concentrically and relatively movably.
A fixing portion fixed to one of the two members;
A seal portion that slidably comes into contact with the other member of the two members;
A bellows portion provided between the seal portion and the fixed portion for causing the seal portion to follow the eccentricity of the other member;
The seal portion is continuously provided on the atmosphere side of the seal lip, which is slidably sealed with the other member, and the force received by the eccentricity of the other member. In a sealing device having a bumper portion made of a rubber-like elastic body that conveys to the bellows portion,
Wherein the bumper portion, to reinforce the bumper portion and the ring is provided with a rigid,
The ring includes a fitting portion fitted into the outer peripheral surface of the bumper portion, and a dust lip that suppresses dust from the atmosphere from reaching the seal lip .

Images