JP2018066397A - Sealing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sealing device which can inhibit leakage of a sealing object fluid even in a state where a rotary ring does not rotate.SOLUTION: A sealing device 10 includes: a rotary ring unit 100 provided at a rotary shaft; and a fixed ring unit 200 provided at a housing. An annular member 110 is provided with a seal lip 124 which is configured to be capable of contacting with an outer peripheral surface of a fixed ring 230 and thereby inhibits entry of a sealing object fluid into a slide part between a rotary ring 130 and the fixed ring 230 from the radial outer side.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a sealing device that seals an annular gap between a rotating shaft and a housing.

  As a sealing device for sealing an annular gap between the rotating shaft and the housing, the end face of the rotating ring provided for the rotating shaft and the end face of the fixed ring provided for the housing are configured to slide. There are known sealing devices. In such a technique, there is a possibility that the fluid to be sealed leaks in a state where the rotating ring is not rotating. In particular, in the case of a sealing device that generates dynamic pressure between the rotating ring and the stationary ring by the rotation of the rotating ring, the fluid to be sealed is leaked by an air flow that generates the dynamic pressure when the dynamic pressure is generated. It is effectively suppressed. Therefore, in a state where the rotating ring is not rotating, there is a possibility that the fluid to be sealed leaks.

International Publication No. 2014/173424 International Publication No. 2014/173495

  An object of the present invention is to provide a sealing device capable of suppressing leakage of a fluid to be sealed even in a state where a rotating ring is not rotating.

  The present invention employs the following means in order to solve the above problems.

That is, the sealing device of the present invention is
A sealing device for sealing an annular gap between a rotating shaft and a housing having a shaft hole through which the rotating shaft is inserted,
A rotating ring unit provided for the rotating shaft;
A stationary ring unit provided for the housing;
A sealing device comprising:
The rotating ring unit is
An annular member fixed to the rotating shaft;
A rotating ring fixed to the annular member;
With
The stationary ring unit is
A reinforcing ring fixed to the shaft hole of the housing;
A stationary ring provided slidably with respect to an end face of the rotating ring;
One end side is fixed to the reinforcing ring, the other end side is fixed to the fixed ring, and an annular elastic body that presses the fixed ring toward the rotating ring,
With
The annular member is configured to be able to come into contact with the outer peripheral surface of the stationary ring, thereby preventing the fluid to be sealed from entering the sliding portion between the rotating ring and the stationary ring from the outside in the radial direction. A lip is provided.

According to the present invention, since the seal lip is provided, even when the rotating ring is not rotating, the invasion of the fluid to be sealed into the sliding portion between the rotating ring and the stationary ring is suppressed, and the fluid to be sealed is sealed. Leakage can be suppressed.

  The seal lip is in contact with the outer peripheral surface of the stationary ring when the rotating ring unit is not rotating, and is directed radially outward by centrifugal force when the rotating ring unit is rotating. It is good to be comprised so that it may leave | separate from the outer peripheral surface of the said fixed ring.

  Thereby, in the state where the rotating ring unit is not rotating, the sealing lip prevents the fluid to be sealed from entering the sliding portion between the rotating ring and the fixed ring. In addition, when the rotary ring unit is rotating, the seal lip and the stationary ring do not slide, so that the sliding resistance is not increased by the seal lip.

  At least one of the sliding surface of the rotating ring with respect to the stationary ring and the sliding surface of the stationary ring with respect to the rotating ring has these sliding surfaces as the rotating ring rotates. It is preferable to provide a dynamic pressure generating groove for generating a dynamic pressure to be separated.

  Thereby, the sliding resistance between the rotating ring and the stationary ring can be reduced or eliminated.

  In addition, said each structure can be employ | adopted combining as much as possible.

  As described above, according to the present invention, leakage of the fluid to be sealed can be suppressed even when the rotating ring is not rotating.

1 is a schematic cross-sectional view of a sealing device according to Embodiment 1 of the present invention. FIG. 2 is a schematic cross-sectional view showing the sealing structure according to the first embodiment of the present invention. FIG. 3 is a schematic cross-sectional view showing the sealing structure according to the first embodiment of the present invention. FIG. 4 is a part of a side view of the rotary ring according to the first embodiment of the present invention. FIG. 5 is a schematic cross-sectional view of a sealing device according to Embodiment 2 of the present invention. FIG. 6 is a schematic cross-sectional view of a sealing device according to Embodiment 3 of the present invention.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be exemplarily described in detail 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. .

Example 1
With reference to FIGS. 1-4, the sealing apparatus which concerns on Example 1 of this invention is demonstrated. 1 is a schematic cross-sectional view of a sealing device according to Embodiment 1 of the present invention. The sealing device according to the present embodiment has a substantially rotationally symmetric shape except for some members, and FIG. 1 shows a cross-sectional view of the sealing device taken along a plane including the central axis. 2 and 3 are schematic cross-sectional views showing a sealing structure according to Embodiment 1 of the present invention. FIG. 2 shows a state where the rotating ring unit is not rotating, and FIG. 3 shows a state where the rotating ring unit is rotating together with the rotating shaft. In addition, about the sealing device in FIG.2 and FIG.3, the cross-sectional view which cut | disconnected the sealing device in the surface containing the center axis line similarly to FIG. 1 is shown. FIG. 4 is a part of a side view of the rotary ring according to the first embodiment of the present invention. In addition, in FIG. 4, CC sectional drawing in a side view is also shown in the inside of a figure.

<Overall configuration of sealing device>
The overall configuration of the sealing device 10 according to the present embodiment will be described. The sealing device 10 according to the present embodiment is used for sealing an annular gap between the rotating shaft 500 and a housing 600 having a shaft hole through which the rotating shaft 500 is inserted. In the present embodiment, in FIGS. 2 and 3, the left side in the figure is the sealed region side (O) in which the fluid to be sealed (oil etc.) is sealed, and the right side in the figure is the sealed region side (O). It is the air side (A) on the opposite side.

  The sealing device 10 according to the present embodiment includes a rotary ring unit 100 provided for the rotary shaft 500 and a fixed ring unit 200 provided for the housing 600. The rotating ring unit 100 is configured to rotate with the rotating shaft 500.

  The rotating ring unit 100 is provided with a metal annular member 110, a rotating ring 130 fixed to the annular member 110, and the annular member 110, and the rotating ring 130 is fitted and fixed to the annular member 110. And an engaged member 120 made of an elastic body for facilitating the operation. The annular member 110 has an inner peripheral surface side cylindrical portion 111 fixed to the outer peripheral surface of the rotating shaft 500 and an outward direction provided at an end portion (end portion on the sealing region side (O)) of the inner peripheral surface side cylindrical portion 111. It has a flange portion 112 and an outer peripheral surface side cylindrical portion 113 provided at the tip of the outward flange portion 112. In addition, the inner peripheral surface side cylindrical portion 111 and the outer peripheral surface side cylindrical portion 113 are configured to extend from the respective end portions of the outward flange portion 112 toward the same direction (direction of the atmosphere side (A)).

  The fitted member 120 is made of an elastic body such as rubber. The fitted member 120 includes an inner peripheral surface side cylindrical portion 121 fixed to the inner peripheral surface of the outer peripheral surface side cylindrical portion 113 of the annular member 110 and an outer periphery fixed to the outer peripheral surface of the outer peripheral surface side cylindrical portion 113. The surface side cylindrical part 123 and the inward flange part 122 provided in the one end side (sealing area | region side (O)) of the internal peripheral surface side cylindrical part 121 are provided. The mating member 120 extends from the portion connecting the inner peripheral surface side cylindrical portion 121 and the outer peripheral surface side cylindrical portion 123 toward the atmosphere side (A) and radially inward, and is provided in the stationary ring unit 200. A seal lip 124 configured to be able to contact the outer peripheral surface of the fixed ring 230 is provided. The seal lip 124 plays a role of suppressing the intrusion of the fluid to be sealed into the sliding portion between the rotating ring 130 and the stationary ring 230 from the outside in the radial direction.

  And the inward flange part 122 in the to-be-fitted member 120 is fixed in a state of being in close contact with the outward flange part 112 in the annular member 110, and connects the inner peripheral surface side cylindrical part 121 and the outer peripheral surface side cylindrical part 123. Is fixed in close contact with the distal end surface of the outer peripheral surface side cylindrical portion 113 of the annular member 110.

  The rotating ring 130 is inserted to a position where it comes into contact with the inward flange portion 122 of the fitted member 120 fixed to the annular member 110, and the outer circumferential surface of the rotating ring 130 is the inner circumferential surface side cylindrical portion 121 of the fitted member 120. Are fitted and fixed in close contact with the inner peripheral surface. The rotating ring 130 is fixed to the annular member 110 with an annular gap formed between the rotating member 130 and the outer peripheral surface of the inner peripheral surface side cylindrical portion 111 of the annular member 110. The rotating ring 130 is made of a highly rigid material such as metal or resin (for example, PPS).

  The fixed ring unit 200 includes a reinforcing ring 210 that is fixed to the shaft hole of the housing 600, a fixed ring 230 that is slidable with respect to the end surface of the rotary ring 130, and presses the fixed ring 230 toward the rotary ring 130. An annular elastic body 220 is provided. The annular elastic body 220 has one end fixed to the reinforcing ring 210 and the other end fixed to the fixed ring 230. The reinforcing ring 210 includes a cylindrical portion 211 fixed to the inner peripheral surface of the shaft hole of the housing 600 by fitting, and an inward flange portion 212 provided at an end portion (end portion on the atmosphere side (A)) of the cylindrical portion 211. And.

The annular elastic body 220 is made of an elastic body such as rubber. The annular elastic body 220 includes a fixed portion 221 that is fixed to the inward flange portion 212 in the reinforcing ring 210, and a tapered portion that decreases in diameter from the inner peripheral surface side of the fixed portion 221 toward the atmosphere side (A). 222. The annular elastic body 220 includes a cylindrical portion 223 extending from the radially inner tip of the tapered portion 222 toward the sealing region side (O), and an inward flange portion 224 provided at the tip of the cylindrical portion 223. Yes. The inward flange portion 224 is fixed to the stationary ring 230 by adhesion. The fixed ring 230 is fixed to the annular elastic body 220 with an annular gap formed between the annular member 110 and the outer peripheral surface of the inner peripheral surface side cylindrical portion 111 of the annular member 110. The fixed ring 230 is made of a highly rigid material such as metal or resin (for example, PPS).

  The sliding surface of the rotating ring 130 with respect to the stationary ring 230 is provided with a plurality of dynamic pressure generating grooves 131 that generate a dynamic pressure that separates these sliding surfaces as the rotating ring 130 rotates. (See FIG. 4). That is, when the rotating ring unit 100 rotates, the stationary ring 230 moves away from the rotating ring 130 against the pressing force of the annular elastic body 220 due to the dynamic pressure by the dynamic pressure generating groove 131. In addition, the sliding surface with respect to the stationary ring 230 in the rotating ring 130 is an end surface of the rotating ring 130 on the stationary ring 230 side (atmosphere side (A)). The sliding surface of the stationary ring 230 with respect to the rotating ring 130 is the end surface of the stationary ring 230 on the rotating ring 130 side (sealing region side (O)).

  Here, as the dynamic pressure generating groove 131, a known technique is appropriately adopted as long as it is a groove that generates dynamic pressure in the gap between the rotating ring 130 and the stationary ring 230 by the rotation of the rotating ring 130. Can do. In this embodiment, as shown in the CC cross-sectional view of FIG. 4, the dynamic pressure generating groove 131 is configured with a smooth curved surface at the groove bottom. Further, the rotating ring 130 is configured to rotate in the clockwise direction in FIG. 4, and the dynamic pressure generating groove 131 is configured such that a deep portion of the groove bottom is biased to the upstream side in the rotating direction. . When the rotary ring 130 is rotated by the dynamic pressure generating groove 131 configured as described above, a fluid (in the case of this embodiment, gas or oil) flows in the direction of arrow F in FIG. As a result, a force in a direction separating the sliding surface of the rotating ring 130 and the sliding surface of the fixed ring 230 is generated. Even if the sliding surface of the rotating ring 130 and the sliding surface of the stationary ring 230 are separated from each other, fluid flows in the circumferential direction due to the dynamic pressure generating grooves 131 in these gaps. The fluid to be sealed does not leak to the atmosphere side (A).

  In the present embodiment, the case where the dynamic ring 131 is provided in the rotary ring 130 has been described as an example. However, a dynamic pressure generating groove may be provided on the sliding surface of the stationary ring 230 with respect to the rotating ring 130 to generate a dynamic pressure that separates these sliding surfaces as the rotating ring 130 rotates. Further, the dynamic pressure generating groove may be provided on both of the sliding surfaces of the rotating ring 130 and the stationary ring 230.

<Operation of sealing device>
In particular, the operation of the sealing device 10 according to the present embodiment will be described with reference to FIGS. 2 and 3. In a state where the rotating shaft 500 is not rotating, the seal lip 124 in the fitted member 120 provided in the annular member 110 is in contact with the outer peripheral surface of the stationary ring 230 (see FIG. 2). Therefore, the fluid to be sealed on the sealing region side (O) is prevented from entering the sliding portion between the rotating ring 130 and the stationary ring 230 from the outside in the radial direction.

  When the rotating shaft 500 rotates, the rotating ring unit 100 also rotates. Thereby, the rotating ring 130 and the fixed ring 230 slide. Further, as described above, dynamic pressure is generated by the dynamic pressure generating groove 131 provided in the rotary ring 130, and the fixed ring 230 moves away from the rotary ring 130 against the pressing force of the annular elastic body 220. To do. However, as described above, in the gap between the sliding surface of the rotating ring 130 and the sliding surface of the stationary ring 230, the fluid in the circumferential direction is generated by the dynamic pressure generating groove 131. There is no leakage to the atmosphere side (A).

  Further, the rotation of the rotary ring unit 100 causes the seal lip 124 to bend radially outward by centrifugal force. Therefore, the tip of the seal lip 124 is separated from the outer peripheral surface of the stationary ring 230 (see FIG. 3). Therefore, sliding resistance due to the seal lip 124 does not occur.

<Excellent point of sealing device according to this embodiment>
According to the sealing device 10 according to the present embodiment, since the seal lip 124 is provided, even when the rotating ring 130 is not rotating, the object to be sealed to the sliding portion of the rotating ring 130 and the stationary ring 230 is sealed. Intrusion of fluid is suppressed, and leakage of the fluid to be sealed can be suppressed.

  Further, when the rotary ring unit 100 is rotating, the seal lip 124 and the stationary ring 230 do not slide, so that the slide lip 124 does not increase the sliding resistance.

  Further, at least one of the sliding surfaces of the rotating ring 130 and the stationary ring 230 according to the present embodiment generates a dynamic pressure that separates these sliding surfaces as the rotating ring 130 rotates. A dynamic pressure generating groove 131 is provided. Thereby, the sliding resistance between the rotating ring 130 and the fixed ring 230 can be reduced or eliminated.

(Example 2)
FIG. 5 shows a second embodiment of the present invention. In the said Example 1, the structure in the case where a rotating ring was fixed by being fitted to the to-be-fitted member provided in this annular member with respect to the annular member was shown. On the other hand, in a present Example, the structure in case a rotary ring is directly fixed with respect to an annular member by adhesion | attachment is shown. Since other configurations and operations are the same as those in the first embodiment, the same components are denoted by the same reference numerals and description thereof is omitted.

  FIG. 5 is a schematic cross-sectional view of a sealing device according to Embodiment 2 of the present invention. The sealing device according to the present embodiment has a substantially rotationally symmetric shape except for some members, and FIG. 5 shows a cross-sectional view of the sealing device taken along a plane including the central axis. In the sealing device 10 according to the present embodiment, only the fixing method of the rotating ring 130 to the annular member 110a is different from that in the first embodiment. That is, in the sealing device 10 according to the present embodiment, the annular member 110a is not provided with the fitted member 120 in the first embodiment. The rotating ring 130 is fixed to the outward flange portion 112 and the outer peripheral surface side cylindrical portion 113 of the annular member 110a by bonding with an adhesive.

  In this embodiment, an elastic seal member 120a is provided on the outer peripheral surface side of the outer peripheral surface side cylindrical portion 113 of the annular member 110a. The seal member 120a includes an outer peripheral surface side cylindrical portion 123 fixed to the outer peripheral surface of the outer peripheral surface side cylindrical portion 113 of the annular member 110a, and a seal lip 124. The seal lip 124 extends from the tip of the outer peripheral surface side cylindrical portion 123 toward the atmosphere side (A) and radially inward, and is configured to be able to contact the outer peripheral surface of the stationary ring 230 provided in the stationary ring unit 200. ing. As in the case of the first embodiment, the seal lip 124 plays a role of suppressing the intrusion of the fluid to be sealed from the radially outer side into the sliding portion between the rotating ring 130 and the stationary ring 230. In the state where the rotary ring unit 100 is rotating, the seal lip 124 is also bent in the radial direction due to centrifugal force, so that the seal lip 124 is separated from the outer peripheral surface of the fixed ring 230. Same as the case.

  Since other configurations are the same as those in the first embodiment, the description thereof is omitted. Also in the sealing device 10 according to the present embodiment configured as described above, the same effects as those of the sealing device 10 according to the first embodiment can be obtained.

(Example 3)
FIG. 6 shows a third embodiment of the present invention. In the said Example 1, the structure in the case where a rotating ring was fixed by being fitted to the to-be-fitted member provided in this annular member with respect to the annular member was shown. On the other hand, in a present Example, the structure in case a rotary ring is directly fixed by crimping with respect to an annular member is shown. Since other configurations and operations are the same as those in the first embodiment, the same components are denoted by the same reference numerals and description thereof is omitted.

  FIG. 6 is a schematic cross-sectional view of a sealing device according to Embodiment 3 of the present invention. The sealing device according to the present embodiment is substantially rotationally symmetric except for some members, and FIG. 6 shows a cross-sectional view of the sealing device cut along a plane including the central axis. In the sealing device 10 according to the present embodiment, only the method of fixing the rotary ring 130 to the annular member 110b is different from that in the first embodiment. That is, in the sealing device 10 according to the present embodiment, the annular member 110b is not provided with the fitted member 120 in the first embodiment. And the rotary ring 130 is being fixed to the annular member 110b by crimping the front-end | tip of the outer peripheral surface side cylindrical part 113 in the annular member 110b (refer to the crimping part 114).

  In this embodiment, an elastic seal member 120b is provided on the outer peripheral surface side of the outer peripheral surface side cylindrical portion 113 of the annular member 110b. The seal member 120b includes an outer peripheral surface side cylindrical portion 123 fixed to the outer peripheral surface of the outer peripheral surface side cylindrical portion 113 of the annular member 110b, and a seal lip 124. The seal lip 124 extends from the tip of the outer peripheral surface side cylindrical portion 123 toward the atmosphere side (A) and radially inward, and is configured to be able to contact the outer peripheral surface of the stationary ring 230 provided in the stationary ring unit 200. ing. As in the case of the first embodiment, the seal lip 124 plays a role of suppressing the intrusion of the fluid to be sealed from the radially outer side into the sliding portion between the rotating ring 130 and the stationary ring 230. In the state where the rotary ring unit 100 is rotating, the seal lip 124 is also bent in the radial direction due to centrifugal force, so that the seal lip 124 is separated from the outer peripheral surface of the fixed ring 230. Same as the case.

  Since other configurations are the same as those in the first embodiment, the description thereof is omitted. Also in the sealing device 10 according to the present embodiment configured as described above, the same effects as those of the sealing device 10 according to the first embodiment can be obtained.

DESCRIPTION OF SYMBOLS 10 Sealing device 100 Rotary ring unit 110, 110a, 110b Annular member 111 Inner peripheral surface side cylindrical part 112 Outward flange part 113 Outer peripheral surface side cylindrical part 114 Clamping part 120 Fit member 120a, 120b Seal member 121 Inner peripheral surface Side cylindrical portion 122 Inward flange portion 123 Outer peripheral surface side cylindrical portion 124 Seal lip 130 Rotating ring 131 Dynamic pressure generating groove 200 Fixed ring unit 210 Reinforcement ring 211 Cylindrical portion 212 Inward flange portion 220 Annular elastic body 221 Fixed portion 222 Tapered portion 223 Cylindrical portion 224 Inward flange portion 230 Fixed ring 500 Rotating shaft 600 Housing

Claims (3)

A sealing device for sealing an annular gap between a rotating shaft and a housing having a shaft hole through which the rotating shaft is inserted,
A rotating ring unit provided for the rotating shaft;
A stationary ring unit provided for the housing;
A sealing device comprising:
The rotating ring unit is
An annular member fixed to the rotating shaft;
A rotating ring fixed to the annular member;
With
The stationary ring unit is
A reinforcing ring fixed to the shaft hole of the housing;
A stationary ring provided slidably with respect to an end face of the rotating ring;
One end side is fixed to the reinforcing ring, the other end side is fixed to the fixed ring, and an annular elastic body that presses the fixed ring toward the rotating ring,
With
The annular member is configured to be able to come into contact with the outer peripheral surface of the stationary ring, thereby preventing the fluid to be sealed from entering the sliding portion between the rotating ring and the stationary ring from the outside in the radial direction. A sealing device provided with a lip.   The seal lip is in contact with the outer peripheral surface of the stationary ring when the rotating ring unit is not rotating, and is directed radially outward by centrifugal force when the rotating ring unit is rotating. The sealing device according to claim 1, wherein the sealing device is configured to be separated from an outer peripheral surface of the stationary ring by being bent.   At least one of the sliding surface of the rotating ring with respect to the stationary ring and the sliding surface of the stationary ring with respect to the rotating ring has these sliding surfaces as the rotating ring rotates. The sealing device according to claim 1, wherein a dynamic pressure generating groove for generating a dynamic pressure to be separated is provided.

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