JPH0446117Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to a sealing device, and particularly to a sealing device that is provided between a rotating body and a non-rotating body to perform sealing.

[Prior art and its problems]

Conventionally, there are sealing devices made of a single rubber substance as shown in FIGS. 2 to 4. In other words, in the sealing device shown in FIG. The rotating shaft 10 is connected at two locations: the groove 11 provided in the body and the non-rotating seal portion B in contact with the rotary shaft 10.
In the sealing device shown in FIG. The seal portion B supports the rotary shaft 10 and performs a sealing action.Furthermore, in the case of the sealing device shown in FIG.
In the two examples above, the rotating seal portion and the non-rotating seal portion B were in point contact, whereas the rotating seal surface A in contact with the rotating shaft 10 and the non-rotating seal portion in contact with the groove 11 were in contact with each other. The rotary shaft 10 is supported within the groove 11 by the sealing surface B, and a sealing action is achieved.

However, in any of the above sealing devices, there is no difference in surface pressure between the rotating seal surface (part) A and the non-rotating seal surface (part) B, and therefore the seal between both parts A and B is There are no particular gender differences, and
In the case of a sealing device as shown in Fig. 4, since the sealing performance on the non-rotating seal surface B is not very good, oil etc. can infiltrate into the non-rotating seal surface B, which causes the rotation. The difference in resistance between the seal surface A and the non-rotating seal surface B disappears, and while the rotating seal surface A should normally move relative to the rotating shaft, the non-rotating seal surface B causes a relative movement. This has caused problems such as relative movement with the side surfaces of the groove, causing wear, and further, making the sealing performance unstable.

This invention solves the problems of the conventional devices as described above, and aims to provide a sealing device that can improve not only sealing properties but also durability.

[Means for solving problems]

In order to solve the above problems, this invention is an annular sealing device disposed between a rotating body and a non-rotating body that supports the rotating body. at least two second lip portions having an annular shape disposed in a groove provided on either one of the non-rotating bodies and abutting the deep surface of the groove on either the inner circumferential surface or the outer circumferential surface; At least two first contacts on either the rotating body or the non-rotating body on the other side of the surface or the outer circumferential surface.
and a lip portion, and when sealing, the surface pressure exerted by the second lip portion on the inner surface of the groove is greater than the surface pressure exerted by the first lip portion on either the rotating body or the non-rotating body. Further, the sealing device is characterized in that the surface pressure applied to each of the first lip portions is different for each lip portion.

[Effect]

By adopting the above-mentioned means, this idea
Sealing performance is improved, and durability is also improved.

〔Example〕

Embodiments of this invention shown in the drawings will be described below.

FIG. 1 shows a state in which the sealing device according to this invention is disposed within a groove 2 provided in a non-rotating body 3 and between the non-rotating body 3 and a rotating shaft 1 which is a rotating body. This sealing device is formed of a flexible material having an annular shape, and has lip portions 4 and 5 that are in contact with the rotating shaft 1 that passes through the annular portion, and a deep groove 2 provided in the non-rotating body 3. Lip portions 6 and 7 in contact with the surface are integrally formed, and the rotating shaft 1
The angles of the lip portions 4 and 5 in contact with the groove 2 are A1 and A2, and the angles of the lip portions 6 and 7 in contact with the inner surface of the groove 2 are B1 and B2.

In general, the shape of the stress distribution generated on the mating seal surface changes depending on the lip angle of the seal, and the sealing performance improves as the slope of the stress distribution increases, that is, as the lip angle decreases. This idea is applied to this idea,
Since the sealing performance differs depending on the size of the lip angle, the manner in which the oil film is formed in the rotating seal portion A and the non-rotating seal portion B differs greatly.

Therefore, if the angle of the rotating seal surface (portion) A is made larger than the angle of the non-rotating seal surface (portion) B, the surface pressure exerted on the rotating shaft 1 by the lip portions 4 and 5 will be: The lip portions 6 and 7 are smaller than the surface pressure acting on the inner surface of the groove 2, and the rotating seal surface A and the non-rotating seal surface B when the rotating shaft rotates.
The torque generated by the rotating seal surface A is always less than the non-rotating seal surface B, and the rotating seal surface A always rotates with the rotating shaft.

As a result, the sealing device does not generate any rotational movement on the non-rotating sealing surface B, and problems such as deterioration of sealing performance due to rotation with the rotating shaft and abrasion with the side surfaces of the groove are eliminated. be.

And, regarding the sealing device based on this invention,
Angle A of lip parts 4 and 5 at rotating seal surface (part)
1, A2 is made larger than the angle B1, B2 of the lip portions 6, 7 on the non-rotating seal surface (part), so the sealing performance of the non-rotating seal surface is always better than that of the rotating seal surface. In addition, since the angles A1 and A2 of the lip portions 4 and 5 on the rotary seal surface are A1≧A2, the surface pressures acting on the lip portions 4 and 5 are different. An oil film is likely to form between them.

Therefore, the lip portions 6, 7 of the non-rotating seal surface
In this case, the formation of an oil film due to the infiltration of sealing materials such as oil is more difficult than in the lip portions 4 and 5 of the rotary seal surface, and in the case of the lip portions 4 and 5 of the rotary seal surface, A1≧A2. An oil film is relatively easily formed between the lip portions 4 and 5, allowing rotation with the rotating shaft. Furthermore, sufficient sealing performance can be ensured by reducing the angle A2 of the lip portion 5.

In the above embodiment, the case was explained in which there were two lip portions as the rotating seal surface A and two lip portions as the non-rotating seal surface.
Without being limited to this, the point is to make the angle of the lip of the rotating seal surface A larger than the angle of the lip of the non-rotating seal surface. It is better to make it smaller than .

[Effect of idea]

By configuring this idea as described above,
With a very simple configuration, it is possible to improve sealing performance and durability, and it also has excellent effects such as being able to reliably prevent twisting around the rotating shaft. It is something that you have.

[Brief explanation of the drawing]

FIG. 1 is a schematic sectional view showing a sealing device according to this invention, and FIGS. 2 to 4 are schematic sectional views showing conventional sealing devices. 1, 10... Rotating body (rotating shaft), 2, 11...
Groove, 3... Non-rotating body, 4, 5... Lip portion of rotating seal surface (part), 6, 7... Lip portion of non-rotating seal surface (part), A... Rotating seal surface (part), B
...Non-rotating seal surface (part), A1, A2...Angle of lip part of rotating seal surface (part), B1, B2...
...The angle of the lip part of the non-rotating seal surface (part).

Claims (1)

[Scope of utility model registration request] An annular sealing device disposed between a rotating body 1 and a non-rotating body 3 that supports the rotating body 1,
The sealing device has an annular shape disposed in a groove 2 provided in either the rotating body 1 or the non-rotating body 3, and has a ring on either the inner circumferential surface or the outer circumferential surface that is in contact with the inner surface of the groove 2. At least two second lip portions 6, 7 that are in contact with each other, and at least two first lip portions 4, 5 that are in contact with either the rotating body 1 or the non-rotating body 3 on the other of the inner circumferential surface or the outer circumferential surface. At the time of sealing, the surface pressure exerted by the second lip portions 6, 7 on the inner surface of the groove is applied by the first lip portions 4, 5 on the other of the rotating body 1 or the non-rotating body 3. The sealing device is characterized in that the surface pressure exerted by each of the first lip portions 4 and 5 is greater than the surface pressure exerted by the first lip portions 4 and 5, and that the surface pressure acting on each of the first lip portions 4 and 5 is different for each of the first lip portions 4 and 5.