JP2001050398A - Sealing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a high-reliable sealing device to improve pressure resistance, sealing ability, and durability. SOLUTION: This sealing device comprises a slipper seal 6 to seal a gap between a pressure reducing seal unit 5 and a housing 2 or a sleeve 4; and a protrusion-form end face lip 3 in a plurality of stages situated at least at either the radial end face 4a or 5a of the sleeve 4 or the pressure reducing seal unit 5 and sealing a gap opposite to radial end faces 4a and 5a. This constitution reduces a pressure applied on the sealing device by a seal member and exerts a reduced pressure on the protrusion-form seal lips in a plurality of stages, whereby deformation due to a high pressure and wear are prevented from occurring and sealing ability and durability are improved.

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 a shaft sealing portion of various devices, and more particularly to a sealing device in which two sealing members are combined.

[0002]

FIG. 3 shows a rubber lip 10 according to the prior art.
FIG. 2 is a diagram illustrating a cross-sectional configuration of a sealing device 101 including a resin lip 103 and a resin lip 103.

[0003] A schematic configuration of the sealing device 101 will be described. A rubber lip 102, a resin lip 103, and a dust lip 104 are fitted into an annular member 110 having a groove 111 for holding an O-ring 112 on the outer peripheral surface. It is fixed in a laminated manner by a radial portion 113 formed by the groove 111 and a caulking portion 114 at the end of the annular member 110.

[0004] Rubber lip 102 and dust lip 104
Is integrated with metal reinforcing rings 102a and 104a by vulcanization molding or the like prior to assembly of the sealing device 101. The resin lip 103 has a flat washer shape made of PTFE, and has a cylindrical jig having an outer diameter substantially the same as that of a shaft to be inserted after assembling. It is bent toward.

[0005] Reference numeral 201 denotes a housing member for fixing the sealing device 101, and 202 denotes a shaft inserted into the housing member 201, which is drawn by imaginary lines in this figure.

The sealing device 101 is provided with a rubber lip 102 on the sealing side M and a resin lip 103 on the atmosphere side O connected to the rubber lip 102 in order to prevent leakage of the sealing fluid on the sealing side M which is particularly high in pressure. It has a configuration.

[0007] The rubber lip 102 exerts sealing properties due to the force of the tip of the lip against the sliding surface 203 (the outer peripheral surface of the shaft 202).

Further, the rubber lip 1
A metal support member 107 is provided that contacts the lower surface of the rubber lip 102 and suppresses excessive deformation of the rubber lip 102 when 02 is deformed.

The resin lip 103 has a thread groove 108.
Is formed, and the leakage of the sealing fluid is prevented by operating a fluid pumping action that moves the sealing fluid slightly leaking in the area of contact with the sliding surface 203 by rotating the shaft 202.

[0010]

However, in the above-mentioned conventional sealing device, since the pressure of the sealing fluid is received by the rubber lip 102, when the pressure of the sealing fluid becomes high, the rubber lip 102 Deformation and excessive surface pressure due to the deformation, abrasion proceeds and leakage occurs.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the prior art. It is an object of the present invention to improve pressure resistance, sealability, durability, and high reliability. It is to provide a sealing device.

[0012]

In order to achieve the above object, according to the present invention, an annular gap between a shaft hole of a housing and a shaft rotatably provided in the shaft hole is sealed. A first annular member fitted and fixed to the shaft and having a first radial portion; and a first radial portion fitted and fixed to the housing and non-sealed from the first radial portion. A sealing device provided with a second annular member having a second radial portion opposed to the first annular member, provided on the housing side of the first annular member, and having a gap with the housing or the second annular member. A sealing member for sealing, and a plurality of protruding seals provided on at least one of the first and second radial portions for sealing an opposing gap between the first and second radial portions. And a lip.

According to this configuration, the pressure applied to the sealing device by the sealing member is reduced, and the reduced pressure is applied to the plurality of projecting seal lips. , Durability can be improved.

Further, by providing a plurality of protruding seal lips for sealing the opposing gap between the first and second radial portions, the pressure difference between the seal lips can be reduced, and the seal lip can be reduced. Deformation can be prevented.

Furthermore, by providing a plurality of stages of seal lips in the first radial portion, the fluid leaking from the seal member to the seal lip is returned radially outward by the action of centrifugal force accompanying rotation of the shaft. Therefore, the sealing property of the seal lip can be improved.

The seal member is made of a resin material, and seals an annular gap between the housing and the shaft in the axial direction. The plurality of seal lips are made of a rubber-like elastic material. It is also preferable to seal the annular gap radially.

Thus, the pressure applied in the axial direction is reduced and sealed by the seal member having small sliding resistance and deformation, and then the rubber is elastically sealed in a plurality of stages in the radial direction. Can be.

It is also preferable that a holding means for holding opposing gaps between the first and second radial portions at predetermined intervals is provided.

Thus, the pressure receiving area of the seal lip can be reduced, and the deformation of the lip can be reduced.

[0020]

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, the shape, and the 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.

FIG. 1 shows a sealing device according to an embodiment of the present invention.
And FIG. The sealing device 10 according to the present embodiment
An annular gap between the shaft 1 and the housing 2 having a cylindrical opening is sealed so that fluid such as oil or gas on the sealed side M does not leak to the atmosphere side O (non-sealed side). is there.

The sealing device 10 includes a pressure reducing seal unit 5 serving as a first annular member, a sleeve 4 serving as a second annular member, and a plurality of projections provided between the pressure reducing seal unit 5 and the sleeve 4. And an end face lip 3 as a seal lip.

The pressure reducing seal unit 5 has a body 9 having a substantially H-shaped cross section having concave portions at both ends fitted and fixed to the shaft 1 with one concave portion facing the shaft 1 and rotating integrally with the shaft 1. I do. The body 9 is formed of a rigid metal or resin that does not deform the concave portion even when a high pressure is applied.
A stopper 8 is provided on the atmosphere side O of the body 9 of the shaft 1.

An O-ring 7 is fitted in the recess on the shaft 1 side of the body 9, and a slipper seal 6 as a sealing member composed of a combination of a rubber ring and an ethylene tetrafluoride resin ring is fitted in the recess on the housing 2 side. It is fitted, and ethylene tetrafluoride resin as a resin material is slidably in contact with the housing 2.

On the atmosphere side O of the pressure reducing seal unit 5, a sleeve 4 is fitted and fixed to the inner peripheral surface of the shaft hole of the housing 2. The sleeve 4 is formed of a metal such as iron or a resin.

Rubber is provided between the radial end surface 5a (first radial portion) on the atmosphere side O of the pressure reducing seal unit 5 and the radial end surface 4a (second radial portion) on the sealing side M of the sleeve 4. A plurality of protruding end face lips 3 of the elastic member are provided.

The end face lip 3 is integrally baked on at least one of the pressure reducing seal unit 5 and the sleeve 4, and is provided so as to seal a fluid flowing from the outermost part to the innermost part of the annular gap. FIG. 1 shows a state provided on the sleeve 4, and FIG. 2 shows a state provided alternately on both the pressure reducing seal unit 5 and the sleeve 4.

With the sealing device 10 configured as described above, the sealing fluid on the sealing side M is sealed in the axial direction by the slipper seal 6 of the pressure reducing seal unit 5, and the fluid leaking from the slipper seal 6 is removed by the pressure reducing seal unit. The end surface lip 3 between the sleeve 5 and the sleeve 4 seals radially.

When the pressure of the sealing fluid on the sealing side M is high,
Although the fluid leaks from the slipper seal 6, the leaked fluid at the end face lip 3 is depressurized, so that the deformation of the end face lip 3 due to the fluid can be reduced, and the end face lip 3 having a plurality of projections is securely sealed. . The protruding lip tip of the end face lip 3 is preferably arranged radially outward as shown in FIG.

Further, since the end face lip 3 seals a fluid flowing from the outside to the inside of the annular gap, if at least one end face lip 3 is provided in the pressure reducing seal unit 5, the shaft 1
The fluid leaking from the slipper seal 6 to the plurality of end face lips 3 can be returned to the outside in the radial direction by the action of the centrifugal force accompanying the rotation of, and the sealing property of the end face lip 3 can be improved.

Further, by setting the end face lip 3 as much as possible, the pressure difference between the lips can be reduced.
The deformation of the lip is reduced, and the sealing performance and durability can be improved.

The distance between the pressure reducing seal unit 5 and the sleeve 4 can be set to a predetermined value by the stopper 8 as a holding means and a stopper (not shown) provided on the housing 2 side, and a stable sealing property can be obtained. Further, by setting the interval small, the pressure receiving area of the end face lip 3 can be reduced, so that the deformation of the lip can be further reduced, and the sealing property and durability can be improved.

Here, the holding means may be stoppers (not shown) provided in the circumferential direction of the radial end faces 4a and 5a on which the end face lip 3 is provided, and the sleeve 4 and the body 9 can be fitted. If so, the fitting portion may be used.

When a fluid leaks from the pressure reducing seal unit 5 and accumulates pressure between the pressure reducing seal unit 5 and the sleeve 4, a sliding surface of the slipper seal 6 is provided with a tapered portion as shown in FIG. By setting the tapered portion on the sealing side, the accumulated pressure between the pressure reducing seal unit 5 and the sleeve 4 can be released.

[0035]

As described above, according to the present invention,
A seal member for sealing a gap between the first annular member and the housing or the second annular member, and a plurality of projecting seal lips for sealing an opposing gap between the first and second radial portions. By providing, the pressure applied to the sealing device by the seal member is reduced, and the reduced pressure is applied to the plurality of projecting seal lips, so that the seal lip can be prevented from being deformed and worn by high pressure, Excellent pressure resistance,
It is possible to provide a highly reliable sealing device with improved sealing performance and durability.

Further, by providing a plurality of protruding seal lips for sealing the opposing gap between the first and second radial portions, the pressure difference between the seal lips can be reduced, and the seal lip Deformation can be prevented.

Further, by providing a plurality of seal lips in the first radial portion, the fluid leaking from the seal member to the seal lip is returned radially outward by the action of the centrifugal force accompanying the rotation of the shaft. Therefore, the sealing property of the seal lip can be improved.

Further, by providing a holding means for holding opposing gaps between the first and second radial portions at predetermined intervals, the pressure receiving area of the seal lip can be reduced, so that deformation of the lip can be reduced. It can be reduced, and the sealing performance and durability can be improved.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of a sealing device according to an embodiment of the present invention.

FIG. 2 is a schematic sectional view illustrating a main part of the sealing device according to the embodiment of the present invention.

FIG. 3 is a schematic sectional view of a conventional sealing device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 shaft 2 housing 3 end face lip 4 sleeve 4a, 5a radial end face 5 pressure reducing seal unit 6 slipper seal 7 O-ring 8 stopper 9 body 10 sealing device

Claims (3)

[Claims] 1. A first seal, which seals an annular gap between a shaft hole of a housing and a shaft rotatably provided in the shaft hole, and is fitted and fixed to the shaft and has a first radial portion. An annular member, and a second annular member fitted and fixed to the housing and having a second radial portion facing the first radial portion on a non-sealing side of the first radial portion. In the sealing device, a seal member provided on the housing side of the first annular member to seal a gap between the housing and the second annular member; and at least one of the first and second radial portions. And a sealing lip having a plurality of protruding stages provided on one of the first and second radial portions to seal an opposing gap between the first and second radial portions. 2. The sealing member is made of a resin material, and seals an annular gap between the housing and the shaft in the axial direction. The plurality of seal lips are made of a rubber-like elastic material. The sealing device according to claim 1, wherein the annular gap is radially sealed. 3. The sealing device according to claim 1, further comprising: holding means for holding opposing gaps between the first and second radial portions at predetermined intervals.