JP2003090440A - Sealing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sealing device not losing a screw pump function from the initial use to the life end thereof. SOLUTION: In a sealing device 2 including a seal lip made of rubber like elastic body, a brush shaped fin 50 having one end connected by two metal rings 20, 30 is wrapped inside of the seal lip in such a manner that another end of the brush shaped fin 50 exists adjacent to a surface layer of a sliding surface 12. A part surrounding the fin relatively projects due to structural effect of the brush shaped fin 50 to form screw shaped projection. The function as a screw pump is maintained by the screw shaped projection.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sealing device provided with a rubber-like elastic seal lip, and more particularly to a seal lip having a thread portion such as a thread groove on a sliding surface thereof.

[0002]

2. Description of the Related Art A conventional oil seal with a screw of this type is
At the time of vulcanization molding of the seal lip, it was molded by transferring the uneven screw pattern formed on the mold.

[0003]

However, in the conventional oil seal with a screw, the screw exhibits its effect in the initial stage of use, but the screw portion (uneven shape) is also worn along with the wear of the seal lip. , The screw pump effect is lost during use, leading to a decrease in sealing performance.

The present invention has been made to solve the above-mentioned problems of the prior art, and the purpose thereof is to:
Another object of the present invention is to provide a sealing device in which a seal lip is provided with a screw portion that does not lose the screw pump effect until the life of the seal itself, instead of the conventional uneven screw portion.

[0005]

To achieve the above object, in a sealing device of the present invention, a reinforcing ring and a seal lip made of a rubber-like elastic body that slides on the surface of a relatively rotating mating member are provided. And a brush-like fin connected to the reinforcing ring is included in a seal lip, and a high-rigidity screw-shaped region having higher rigidity than other portions is formed on the surface of the seal lip during rotation. Characterize.

[0006] As a result, normally, in the sealing device,
Due to the fluid pressure present on the sliding surface between the seal lip and the mating member, the vicinity of the sliding surface is deformed, but in the present invention, due to the structural material effect of the brush-shaped fins present in the seal lip portion, Since the brush-shaped fin peripheral region has higher rigidity and is less likely to be deformed than other portions, the fin peripheral region relatively projects to form a protrusion in the screw-shaped high-rigidity region. Then, the sealing device can be provided with a function as a screw pump by the screw-shaped protrusions.

The brush-shaped fins connected to the reinforcing ring may extend from the reinforcing ring inside the sealing device toward the surface layer of the sliding surface of the sealing device.

As a result, an area having different rigidity (brush-shaped fin peripheral area) is provided from the surface layer of the sliding surface to the inside in the thickness direction, and even if the seal lip is worn, the screw-shaped area having different rigidity slides. It appears on the moving surface and it is possible to maintain the screw pump effect on the seal lip from the beginning of use to the end of its life.

The reinforcing ring, the brush-like fins sandwiched and fixed by the reinforcing ring, and the rubber-like elastic body may be integrally molded.

By doing so, the material inflow from the dust lip side (B inflow method) is taken into consideration in the direction of the brush fins.
By using this together with the ring-shaped nozzle, material saving can be achieved.
Further, since the brush-shaped fins as the screw-shaped structural material are present in advance, it is not necessary to consider the change in the behavior of the material flow, which may be affected by the die-transfer screw.

The screw-shaped high-rigidity region may be formed in the shape of the reinforcing ring or in the shape of the brush-shaped fin sandwiched and fixed by the reinforcing ring.

Thus, by changing the shape of the brush-like fins or the shape of the reinforcing ring, it is possible to optimize the shape (range, distribution) of the screw-shaped high rigidity region.

As described above, in the present invention, by "inclusion of the brush-shaped fin", the brush-shaped fin plays a role of a structural material for supporting the screw-shaped high rigidity region, and further in the thickness direction of the sliding surface. And can be formed thick.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be exemplarily described in detail below with reference to the drawings. However, the dimensions of the components described in this embodiment,
Unless otherwise specified, the material, the shape, the relative arrangement, and the like are not intended to limit the scope of the present invention thereto.

The configuration of the sealing device according to this embodiment will be described with reference to FIG. FIG. 1 is a half sectional view showing a sealing device according to an embodiment of the present invention.

The oil seal 2 shown in FIG. 1 is a sealing device for an inner peripheral seal that slides between itself and the shaft. Oil seal 2
The main material is a rubber-like elastic body and is vulcanized and molded.

When the oil seal 2 is classified according to its shape, an outer peripheral cylindrical fitting portion 4 which is thickly inserted and fixed in a housing hole, a plate portion 6 extending inward from an atmosphere side end portion of the cylindrical fitting portion 4,
The seal lip portion inside the plate portion 6 is divided into two,
One is a main lip 8 that is formed by obliquely bending to the sealed fluid side, and a dust lip 10 that extends obliquely to the atmosphere side, and a metallic reinforcing ring 20 that is inserted inside the oil seal 2, 21, a spring 40 attached to the main lip 8, and a brush-like fin 50 sandwiched by metal rings.

The main lip 8 is a basic lip having a function of sealing a sealing fluid having a pressure and leaking along the rotating shaft. And village and dust lip 10
Main lip 8 is sand particles, dust, muddy water from the atmosphere side.
Has a supplementary function of preventing the leakage of the sealing fluid by invading the sliding surface of the seal.

The auxiliary rings 20 and 30 are formed by pressing a metal plate and have a substantially L-shaped cross section. The outer peripheral cylindrical portions 22 and 32 and the cylindrical portions 22 and 32 on the atmosphere side. It is composed of flange portions 24 and 34 extending inward from the end portions. The reinforcing rings 20 and 30 are inserted into the tubular fitting portion 4 and the plate portion 6 of the oil seal 2 during vulcanization molding. The function of the reinforcing rings 20 and 30 is to reinforce the oil seal 2 to increase its rigidity and to fix the brush-like fins.

The spring 40 tightens the tip of the main lip 8 on the rotary shaft to improve the contact followability of the lip with respect to the vibration during rotation, and also to prevent the leakage of the sealing fluid due to the vibration of the rotary shaft. There is.

The main lip 8 is in contact with the rotating shaft at a sliding surface 12 having a certain width.

FIG. 2 shows an example of making a metal ring with brush-like fins.

As shown in FIG. 2, (a) a linear brush made of resin or metal collected on the base side is prepared,
(B) The base side of the brush is rolled up and bonded in a ring shape. Next, (c) the brush ring is tilted inward, the brush is directed toward the center of the ring, and the tilted brush ring is sandwiched between two metal rings from above and below and fixed by sandwiching between the two rings from above and below. (Fixing method as found in Teflon® rotary seals).

Needless to say, the orientation of the brush-like fins needs to be related to the rotation direction of the rotary shaft in order to exert the screw pump action, but in the present invention, the fins are arranged toward the center point rather than in a specific left and right direction. There is. This is because the fins follow the rotation direction and change directions due to the frictional force with the shaft, so that the fins can exhibit the performance as both rotary seals.

The bristle length of the brush was adjusted in advance so as to reach the vicinity of the surface of the seal lip sliding surface 12.

Usually, in the oil seal, the vicinity of the sliding surface is deformed by the fluid pressure present on the sliding surface between the seal lip and the mating member. In the present invention, due to the structural material effect of the brush-shaped fins present in the seal lip portion, the brush-shaped fin peripheral region has higher rigidity and is less likely to be deformed than other portions, so that the fin-shaped peripheral region is relatively protruded. To form a screw-shaped protrusion. The oil seal can have a function as a screw pump by the rod-shaped projection.

By providing the regions having different rigidity (brush-shaped fin peripheral regions) from the surface layer of the sliding surface to the inside in the thickness direction, the screw-shaped regions having different rigidity are worn even if the seal lip is worn. Appearing like a sliding surface, it is possible to maintain the screw pump effect on the seal lip from the beginning of use to the end of its life.

In particular, the material inflow (B inflow method) from the dust lip side is suitable in consideration of the direction of the brush-like fins, and the material can be saved by using it together with the ring-shaped nozzle.
Further, since the brush-like fins as the screw-like structural material are present in advance, it is not necessary to consider the change in the behavior of the material flow which may be affected by the die-transfer screw.

Further, by changing the shape of the brush-shaped fins or the shape of the metal ring, it is possible to optimize the shape (range, distribution) of the screw-shaped high rigidity region.

FIG. 3 is a view showing another example of the brush-shaped fin according to the present embodiment. In this case, the shape of the portion of the upper and lower two metal rings sandwiching the brush is press-formed into a sine curve shape, so that the brush fin shape also has a sine curve.

As a result, the range of the screw-shaped high rigidity portion can be distributed in a sine curve shape. As a result, even with a conventional product in which a sine curve shaped screw is transferred to a seal lip called a wave lip, a seal capable of exerting a screw pump function can be achieved regardless of wear of the sliding surface.

As described above, in the present invention, by "inclusion of the brush-shaped fins", the brush-shaped fins serve as a structural material that supports the screw-shaped high rigidity region, and further in the thickness direction of the sliding surface. And can be formed thick.

[0033]

As described above, in the conventional oil seal having the concavo-convex threaded portion, as the seal lip wears, the threaded portion is worn away, the screw pump effect disappears, and the sealing performance deteriorates. On the other hand, in the sealing device of the present invention, as the wear of the seal lip progresses, a screw-shaped portion having different rigidity always appears on the sliding surface, so that the screw pump effect is not lost and the life is high from the initial use to the lip life. It is possible to maintain the sealing performance.

[Brief description of drawings]

FIG. 1 is a half sectional view showing a sealing device according to an embodiment.

FIG. 2 is a diagram showing an example of a metal ring with a brush-shaped fin according to the embodiment and a manufacturing method thereof.

FIG. 3 is a view showing another example of the metal ring with brush-like fins according to the embodiment.

[Explanation of symbols]

2 Oil seal (sealing device) 4 Cylindrical fitting part 6 Plate part 8 main lip 10 dust lip 12 Sliding surface 20 Reinforcing ring (lower metal ring) 22, 32 Cylindrical part 24, 34 Flange part 30 Reinforcing ring (upper metal ring) 40 spring 50 brush fins

Claims (4)

[Claims] 1. A sealing device comprising a reinforcing ring and a seal lip made of a rubber-like elastic body that slides on the surface of a relatively rotating mating member, wherein a brush-shaped fin connected to the reinforcing ring comprises: A sealing device which is included in a seal lip and which has a screw-like high rigidity region having high rigidity partially formed on a sliding surface of the seal lip during rotation. 2. The sealing device according to claim 1, wherein the brush-like fins connected to the reinforcing ring extend from the reinforcing ring inside the sealing device toward the surface layer of the sliding surface of the sealing device. . 3. The sealing device according to claim 1, wherein the reinforcing ring, the brush-like fins sandwiched and fixed by the reinforcing ring, and a rubber-like elastic body are integrally molded. 4. The screw-shaped high-rigidity region is configured by the shape of the reinforcing ring or the shape of the brush-shaped fin sandwiched and fixed by the reinforcing ring. Or the sealing device according to 3.