JP2000065217A - Sealing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sealing device capable of keeping bearing pressure against the other member due to the compression of the sealing device, and of enhancing the sealing properties of the sealing device against the other member. SOLUTION: In this sealing device 1 equipped with a lip part 5 brought into contact with a shaft 3 while being sealed so as to be freely slid, a sealing part 6 keeping sealing properties against a housing 2, and with an engaging part 7 which has a reinforcing ring 4 supporting the sealing part 6 onto a shaft axial part 4a, and concurrently, is fixed to the housing 2, a flange part 4c which has the engaging part 6 held between the housing 2 and the reinforcing ring thin in thickness, and receives the pressure P of a sealing subject fluid side O, is provided for the O end part of the sealing subject fluid side in the axial direction part 4a of the reinforcing ring 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sealing device used for sealing a fluid, for example, applied under high pressure conditions.

[0002]

2. Description of the Related Art Conventionally, as this type of sealing device, there is, for example, one shown in FIG. That is, the sealing device 100 is mounted between a housing 101 and a shaft 102 inserted through the housing 101, which are assembled concentrically with each other.
The housing 101 and the shaft 102 relatively move in the axial direction by the action of hydraulic oil such as high-pressure oil.
The lip 104 of the sealing device contacts the sliding surface of the shaft 102 to prevent leakage of hydraulic oil.

[0003] The sealing device 100 includes a reinforcing ring 10 having an L-shaped cross section.
3, a fitting portion 106 having a lip portion 104 on the inner peripheral side, a reinforcing ring 103, and a sealing portion 105 for maintaining the hermeticity when fitted to the housing 101 on the outer peripheral side of the reinforcing ring 103;
It has.

[0004] The sealing property of the sealing section 105 is determined by the sealing device 10.
The outer peripheral surface pressure with the housing 101 is maintained by the compression of the sealing portion 105 when 0 is attached, so that the sealing portion 105 is in close contact.

The lip portion 104 and the sealing portion 105
It is formed by vulcanization molding, and a rubber-like elastic material, which is a material inside the mold at the time of molding, heats and flows, and the
3 and extends over the axial portion 103a.

The outer periphery of the lip 104 is provided with a lip 10
A spring is provided to maintain the tension on the fourth shaft 102.

Further, a backup ring 107 for preventing the lip 104 from being turned upside down when the lip 104 slides with respect to the shaft 102 is provided on the opposite side A of the fluid to be sealed from the lip 104.

In such a sealing device 100, the radial portion 103b of the reinforcing ring 103 is pressed against the abutting member 108 so as not to move due to the pressure P of the hydraulic oil, while being fitted to the inner peripheral surface of the housing 101. ing.

[0009]

However, in the above prior art, the thickness of the sealing portion 105 sandwiched between the axial portion 103a of the reinforcing ring 103 and the housing 101 is large, and the sealing portion 105 is provided on the side of the fluid to be sealed. A force due to the pressure P of the hydraulic oil O is applied, and the sealing portion 105 is deformed toward the anti-sealing target fluid side A, so that the outer peripheral surface pressure against the housing 101 cannot be maintained due to the compression due to the mounting, and the sealing performance is reduced. May be reduced.

When the sealing device 100 is used for a long time,
If the rubber-like elastic material of the sealing portion 105 is sagged (permanently deformed), the sealing performance is reduced. If the outer peripheral surface pressure against the housing 101 cannot be maintained, stable sealing performance for a long period of time is maintained. Was difficult.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the prior art, and it is an object of the present invention to maintain the surface pressure on the other member by compressing the sealing portion and to reduce the other member of the sealing portion. It is an object of the present invention to provide a sealing device that improves the sealing performance of the device.

[0012]

In order to achieve the above object, according to the present invention, two concentrically assembled parts are provided.
A lip portion that seals the annular gap of the members and slidably and sealingly contacts one of the two members, a sealing portion that maintains the sealing property with respect to the other member, and the sealing portion. A sealing device having a reinforcing ring supported in the axial direction portion and a fitting portion fixed to the other member,
A pressure receiving portion for reducing the thickness of the sealing portion sandwiched by the other member and receiving a pressure on the fluid to be sealed is provided at an end of the reinforcing ring on the side of the fluid to be sealed in the axial direction. .

Therefore, the thickness of the sealing portion sandwiched between the other member and the pressure receiving portion of the reinforcing ring is small, and the force due to the pressure on the fluid to be sealed can be received by the pressure receiving portion. No pressure force is applied to the sealing part on the fluid side to be sealed, so that the sealing part can be prevented from being deformed to the side opposite to the fluid to be sealed, and can be compressed by mounting to maintain the surface pressure against the other member. The sealing performance of the part with respect to the other member can be improved.

Preferably, the pressure receiving portion is a flange portion extending toward the other member.

[0015] This allows the flange portion to receive the force due to the pressure on the side of the fluid to be sealed.

[0016]

Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 is a sectional view showing a sealing device 1 according to an embodiment of the present invention. In FIG. 1, a sealing device 1 is mounted concentrically between a housing 2 as the other of the two members and a shaft 3 as one member inserted into the housing 2. The housing 2 and the shaft 3 move relative to each other in the axial direction due to the action of hydraulic oil such as high-pressure oil. The lip 5 of the sealing device hits the sliding surface of the shaft 3 to prevent leakage of hydraulic oil. Preventing.

The sealing device 1 has a lip part 5 on the inner peripheral side of the reinforcing ring 4 and a sealing part 6 for maintaining the sealing when the reinforcing ring 4 and the housing 2 on the outer peripheral side of the reinforcing ring 4 are fitted. And a fitting portion 7.

The sealing performance of the sealing portion 6 is maintained by increasing the outer peripheral surface pressure on the housing 2 by compressing the sealing portion 6 when the sealing device 1 is mounted.

The lip portion 5 and the sealing portion 6 are formed by vulcanization molding, and a rubber-like elastic material, which is a material inside the mold at the time of molding, is heated and flows, and the axial portion 4a of the reinforcing ring 4 is formed. It has become an integral thing by overcoming.

The reinforcing ring 4 includes an axial portion 4a and a radial portion 4b.
A flange portion 4c as a pressure receiving portion extending in the outer diameter direction of the housing 2 is provided at an end of the axial direction portion 4a of the reinforcing ring 4 on the side of the fluid to be sealed, which is outside the flange portion 4c. The thickness of the sealing portion 6 sandwiched between the radial end portion and the housing 2 is as small as possible.

On the outer periphery of the lip portion 5, the shaft 3 of the lip portion 5
A spring is provided to maintain the tension against

The fluid side A of the lip 5 opposite to the fluid to be sealed is
In addition, a backup ring 8 is provided to prevent the lip 5 from being turned upside down when the lip 5 slides on the shaft 3.

The sealing device 1 is fitted on the inner peripheral surface of the housing 2, but presses the radial portion 4 b of the reinforcing ring 4 against the abutting member 9 so as not to move due to the pressure of the hydraulic oil. Let me.

Therefore, in the sealing device 1 of the present embodiment,
The thickness of the sealing portion 6 sandwiched between the outer diameter end of the flange portion 4c of the reinforcing ring 4 and the housing 2 is small, and the force due to the pressure P on the fluid side O to be sealed can be received by the flange portion 4c. No force due to the pressure P is applied to the sealing portion 6 on the anti-sealing target fluid side A, and the deformation of the sealing portion 6 on the anti-sealing target fluid side A can be prevented. This can be maintained, and the sealing performance of the sealing portion 6 is improved as compared with the related art.

Further, even if the sealing device 1 is used for a long period of time and the rubber-like elastic material of the sealing portion 6 is sagged (permanently deformed), the outer peripheral surface pressure against the housing 2 is maintained even if the sealing performance is reduced. Therefore, the sealing portion 6 can maintain stable sealing performance for a long period of time.

Although the present embodiment is provided with the flange portion 4c, the present invention is not limited to such a sealing device. The thickness of the sealing portion sandwiched between the housing 2 is reduced, and What is necessary is just to be provided with the pressure receiving part which receives the pressure P.

[0028]

According to the present invention, a pressure receiving portion for reducing the thickness of the sealing portion sandwiched between the other member and the pressure on the side of the fluid to be sealed is provided at the end of the reinforcing ring on the side of the fluid to be sealed in the axial direction. With this configuration, the thickness of the sealing portion sandwiched between the other member and the pressure receiving portion of the reinforcing ring is small, and the force due to the pressure on the fluid to be sealed can be received by the pressure receiving portion. No pressure force is applied to the sealing part on the fluid side to be sealed, so that the sealing part can be prevented from being deformed to the side opposite to the fluid to be sealed, and can be compressed by mounting to maintain the surface pressure against the other member. The sealing performance of the part with respect to the other member can be improved.

Further, even if the sealing device is used for a long time and the sealing portion is sagged (permanently deformed) and the sealing performance is reduced, the surface pressure against the other member is maintained as described above. The sealing part can maintain stable sealing performance for a long time.

The pressure receiving portion is a flange portion extending toward the other member, so that the flange portion can receive a force due to the pressure on the fluid to be sealed.

[Brief description of the drawings]

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

FIG. 2 is a sectional view showing a conventional sealing device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Sealing device 2 Housing 3 Shaft 4 Reinforcement ring 4a Axial part 4b Radial part 4c Flange part 5 Lip part 6 Sealing part 7 Fitting part 8 Backup ring 9 Butt member

Claims (2)

[Claims] 1. A lip portion which seals an annular gap between two members which are assembled concentrically with each other, and which slidably and slidably contacts one of the two members, and a seal member which slidably contacts the other member. A sealing device comprising: a sealing portion that maintains sealing performance; and a fitting portion that has a reinforcing ring that supports the sealing portion in an axial direction portion and that is fixed to the other member. A sealing device, comprising: a pressure receiving portion for reducing the thickness of the sealing portion sandwiched by the other member and receiving a pressure on the fluid to be sealed, at an end of the portion on the side of the fluid to be sealed. 2. The sealing device according to claim 1, wherein the pressure receiving portion is a flange portion extending toward the other member.