JP2018100730A - Sealing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sealing device which is used in an apparatus having two members which relatively rotate, suppresses a rise of the pressure in an apparatus internal space at the replenishment of a lubricant, and holds the replenished lubricant in the apparatus internal space for a long period of time.SOLUTION: A sealing device comprises a first seal member 10 which is fixed to an inner face of an outside member out of two members which relatively rotate, and in which the inside member out of the two members which relatively rotate slides, or an external peripheral face of the member fixed to the inside member slides. The sealing device seals an apparatus internal space with a lubricant in the apparatus internal space. A slit 50 for permitting the passage of the lubricant from the apparatus internal space when the pressure of the apparatus internal space exceeds a constant value is formed at the first seal member.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a sealing device used in an apparatus having two members that rotate relative to each other.

  Conventionally, as a sealing device of this type, for example, as described in Patent Document 1, one of two relatively rotating members, for example, a rotary seal member called a slinger fixed to a rotating shaft, and two members rotating relatively On the other hand, for example, a sealing structure having a fixed seal member fixed to an inner surface of a shaft hole in which a rotation shaft is disposed is known. Such a sealing device is used to seal a lubricant, for example grease, in the interior space of the device. Normally, the rotary seal member is provided with a flange, and this flange prevents or reduces the intrusion of mud and dust from the atmosphere side into the internal space of the equipment. For example, a railway vehicle carriage, a sintered pallet carriage, a construction machine Such sealing devices are used in equipment used in mud or dusty environments such as truck trunnion suspensions and agricultural machinery.

Japanese Patent No. 4979744

  For equipment having this type of sealing device, it may be necessary to replenish the interior space of the equipment with a lubricant. Reasons for replenishment include the need for replacement due to deterioration of the lubricant and a reduction in the amount due to leakage of the lubricant. In replenishment, care should be taken so that the pressure in the internal space of the device does not become too high due to the injection of the lubricant, and it is desirable that the replenished lubricant be held in the internal space of the device over a long period of time.

  Therefore, the present invention is used in a device having two members that rotate relative to each other, suppresses an increase in pressure in the device internal space when the lubricant is replenished, and the replenished lubricant is held in the device internal space for a long period of time. An object is to provide a sealing device.

  In order to solve the above-described problems, a sealing device according to the present invention is a sealing device that seals a lubricant in an internal space of an apparatus to the internal space of the apparatus, and includes an outer member of two members that rotate relative to the apparatus. An inner member of two members which are fixed to the inner surface and relatively rotate, or a first seal member on which an outer peripheral surface of the member fixed to the inner member slides is provided, and the pressure in the internal space of the device is a constant value The first seal member is provided with a slit that allows the lubricant to pass from the device internal space.

  In this sealing device, the slit provided in the first seal member allows the lubricant to pass from the device internal space when the pressure in the device internal space exceeds a certain value, and in other cases, lubrication is performed. It functions as a valve that prevents the agent from passing through. Therefore, an increase in pressure in the device internal space is suppressed when the lubricant is supplied, and the lubricant is held in the device internal space for a long time after the supply.

  The slit is preferably provided in a wall portion that does not contact other members of the first seal member. In this case, other members do not slide in the vicinity of the slit, and since there is no wear due to sliding, the performance of retaining the lubricant is unlikely to deteriorate.

  The first seal member includes an elastic ring formed of an elastic body that is brought into close contact with the outer member, and a reinforcing ring formed of a rigid body that reinforces the elastic ring, and the slit includes the slit It is preferable that a through hole through which the lubricant passes from the slit is formed at a position formed on the elastic ring and overlapping the slit of the reinforcing ring. In this configuration, the first seal member has a double structure of an elastic ring and a reinforcing ring, and the rigidity is enhanced by the reinforcing ring. By forming a slit in the elastic ring and forming a through hole at a position overlapping the slit of the reinforcing ring, the lubricant passes through the slit and the through hole from the device internal space when the pressure in the device internal space exceeds a certain value. Since it is not necessary to provide the reinforcing ring with through holes or other locations that weaken the rigidity at other locations, a decrease in the stiffness of the reinforcing ring and thus the first seal member is minimized.

  In the first seal member, it is preferable that a plurality of the slits having the same size are arranged at equiangular intervals around the inner member. Since the plurality of slits having the same dimensions are arranged at equiangular intervals in this way, not only is the sealing device easy to manufacture, but the pressure in the internal space of the device is constant when replenishing the lubricant. If it exceeds, the lubricant flows out through these slits at a substantially uniform flow rate. Therefore, the load on the portion downstream of the slit of the lubricant outflow path is equalized.

  Preferably, the sealing device includes a second seal member having a sleeve fixed to the inner member, and a flange that is integrally connected to an end portion on the atmosphere side of the sleeve and radially spreads outside the sleeve, The first seal member includes a lip portion on which an outer peripheral surface of the sleeve slides, and an outer annular body fixed to the inner surface of the outer member, and the second seal member includes an outer edge of the flange. And a dust lip that extends radially outward from the inner circumferential surface of the outer annular body of the first seal member. In this configuration, the flange of the second seal member blocks intrusion of mud and dust from the atmosphere side into the equipment internal space. Further, the dust lip portion of the second seal member more reliably prevents intrusion of mud and dust from the atmosphere side into the equipment internal space. As described above, since the slit provided in the first seal member causes the lubricant to flow out when the pressure in the internal space of the device exceeds a certain value, the slit is provided between the second seal member and the first seal member. Sealing performance (provided at the lip and dust lip) does not have to be reduced due to lubricant spills, the lip sealing performance to the lubricant and the dust lip sealing to mud and dust It is possible to firmly form the lip portion and the dust lip portion so as to enhance the stopping performance.

  In the present invention, the slit provided in the first seal member functions as a valve that allows the lubricant to pass from the device internal space when the pressure in the device internal space exceeds a certain value. Therefore, an increase in pressure in the internal space of the device is suppressed when the lubricant is replenished, and an unexpected breakage of the sealing device is prevented, and an increase in rotational torque of the rotating shaft caused by the high-pressure lubricant is also suppressed. Further, after the replenishment, the slit is closed to prevent the lubricant from passing therethrough, so that the lubricant is held in the device internal space for a long time. Further, since the slit is provided in the first seal member, it is not necessary to increase the dimension of the sealing device, particularly the length in the axial direction, in order to provide a special lubricant outflow path. Furthermore, since a slit as a valve is formed in the sealing device, particularly the first seal member, when the outflow performance or retention performance of the lubricant is reduced, there is no need to replace other parts of the device. The sealing device or the first sealing member can be easily replaced.

It is sectional drawing of the sealing device which concerns on 1st Embodiment of this invention. It is sectional drawing of the rotation sealing member of the sealing device of FIG. It is sectional drawing of the fixed sealing member of the sealing device of FIG. FIG. 4 is an end view of the fixed seal member of FIG. 3. It is an end elevation of the modification of the fixed seal member of FIG. It is sectional drawing of the sealing device which concerns on the modification of 1st Embodiment. It is sectional drawing of the sealing device which concerns on the other modification of 1st Embodiment. It is sectional drawing of the sealing device which concerns on the further another modification of 1st Embodiment. It is sectional drawing of the sealing device which concerns on the further another modification of 1st Embodiment. FIG. 10 is an end view of the fixed seal member of FIG. 9. It is sectional drawing of the sealing device which concerns on 5th Embodiment of this invention.

Hereinafter, various embodiments according to the present invention will be described with reference to the accompanying drawings.
First Embodiment FIG. 1 is a diagram according to a first embodiment of the present invention, and shows a sealing device used in a device having two members that rotate relative to each other.

  The sealing device 1 seals the space between the rotating shaft (inner member) 4 and the inner surface of the shaft hole 6 of the housing (outer member) in which the rotating shaft 4 is inserted and disposed, thereby providing a device internal space S. Prevents or reduces fluid leakage from the atmosphere to the atmosphere A side. The rotating shaft 4 has a cylindrical shape, the shaft hole 6 has a circular cross section, and the sealing device 1 has a substantially annular shape, but only the left side portion thereof is shown in FIG.

  The sealing device 1 includes a rotary seal member (second seal member) 8 called a slinger which is fixed to the rotary shaft 4 and rotates integrally with the rotary shaft 4, and a fixed seal member (first seal member) fixed to the shaft hole. It is an assembly which is a combination with the seal member 10. The rotary seal member 8 and the fixed seal member 10 cooperate to seal the lubricant in the device internal space S. The rotary seal member 8 is fitted to the fixed seal member 10. When a large force is applied along the axial direction of the sealing device 1, the fitting is released and can be removed.

  The rotary seal member 8 includes a sleeve 12 fixed to the rotary shaft 4, and a flange 14 that is integrally connected to the end of the sleeve 12 on the atmosphere A side and radially spreads outside thereof. The method of fixing the rotating shaft 4 and the sleeve 12 is not limited, but may be an interference fit, for example. The rotary seal member 8 has a double structure, and includes an elastic ring 16 formed of an elastic body, for example, an elastomer, and a rigid body, for example, a metal reinforcing ring 18, which closely contacts the elastic ring 16 and reinforces the elastic ring 16. .

  As shown in FIG. 2, the sleeve 12 is a part of the elastic ring 16 and is fixed to the outer periphery of the inner cylindrical part 16 a that is a part of the inner cylindrical part 16 a that is in close contact with the rotating shaft 4 and a reinforcing ring 18. The outer cylindrical portion 18a. The flange 14 is a part of the elastic ring 16 and is disposed on the atmosphere A side, and the flange 14 is a part of the reinforcing ring 18 and is disposed on the equipment internal space S side and is fixed to the elastic flange part 16b. And a rigid flange portion 18b.

  As shown in FIG. 3, the fixed seal member 10 includes an outer annular body 22, an intermediate annular body 24 disposed coaxially with the outer annular body 22 on the radially inner side of the outer annular body 22, and a radius of the intermediate annular body 24. The inner annular body 26 is disposed coaxially with the intermediate annular body 24 on the inner side in the direction. The outer annular body 22 and the intermediate annular body 24 are connected by an outer flange 23 in the device internal space S, and the intermediate annular body 24 and the inner annular body 26 are connected by an inner flange 25 on the atmosphere A side.

  The fixed seal member 10 also has a double structure, and has an elastic ring 28 formed of an elastic body, for example, an elastomer, and a rigid body that reinforces the elastic ring 28, for example, a metal reinforcing ring 30. A part of the reinforcing ring 30 is embedded in the elastic ring 28 and is in close contact with the elastic ring 28.

  As shown in FIG. 1, the outer annular body 22 of the fixed seal member 10 is an outer seal portion fixed to the shaft hole 6. The fixing method is not limited, but may be an interference fit, for example. The reinforcing ring 30 applies a force toward the radially outer side to the elastic body portion of the outer annular body 22, and firmly presses the elastic body portion of the outer annular body 22 against the shaft hole 6. However, the reinforcing ring 30 is not necessarily indispensable. A garter spring 32 for compressing the inner annular body 26 radially inward is wound around the inner annular body 26. As shown in FIG. 3, the inner annular body 26 is formed with a receiving groove 34 that receives the garter spring 32.

  The elastic ring 28 of the fixed seal member 10 further includes a seal lip portion 36, a dust lip portion 38, and a dust lip portion 40. The seal lip portion 36 is a protrusion that protrudes inward from the inner annular body 26 and is continuous in the circumferential direction, and has two inclined surfaces. The seal lip portion 36 is in sealing contact with the outer peripheral surface of the sleeve 12 of the rotary seal member 8 to prevent or reduce fluid leakage from the device internal space S to the atmosphere A side. When the rotary seal member 8 rotates together with the rotary shaft 4, the outer peripheral surface of the sleeve 12 slides with respect to the seal lip portion 36. The garter spring 32 applies a force for pressing the seal lip portion 36 against the rotating shaft 4 to the seal lip portion 36.

  The dust lip 38 extends obliquely from the connecting portion of the inner annular body 26 and the inner flange 25 to the atmosphere A side and to the inside. The dust lip 40 extends from the inner flange 25 to the atmosphere A side and is bent. The tip of the dust lip portion 38 is in sealing contact with the outer peripheral surface of the sleeve 12 of the rotary seal member 8, and when the rotary seal member 8 rotates with the rotary shaft 4, the outer peripheral surface of the sleeve 12 slides against the dust lip portion 38. Move. The tip of the dust lip 40 contacts the rigid flange 18b of the flange 14 of the rotary seal member 8. When the rotary seal 8 rotates with the rotary shaft 4, the rigid flange 18b slides against the dust lip 40. Move.

  The rotary seal member 8 further includes a dust lip portion 42 that extends radially outward from the outer edge of the flange 14. The dust lip 42 extends obliquely from the outer edge of the flange 14 to the atmosphere A side and to the outside. The tip of the dust lip portion 42 is in sealing contact with the inner peripheral surface of the rigid portion of the outer annular body 22, and when the rotary seal member 8 rotates together with the rotary shaft 4, the dust lip portion 42 becomes the outer annular body of the stationary seal member 10. 22 slides against the inner peripheral surface of the rigid body portion.

  The dust strips 38, 40, and 42 mainly play a role of preventing entry of foreign matter (mud and dust) from the atmosphere A side to the equipment internal space S side. However, the dust lip portions 38, 40, 42 may prevent the lubricant from flowing out from the device internal space S side to the atmosphere A side. As is clear from comparison between FIG. 1 and FIG. 2 or FIG. 3, the seal lip portion 36 and the dust lip portions 38 and 40 are deformed by contacting the rotary seal member 8, and the dust lip portion 42 is fixed to the fixed seal. It is deformed by contacting the member 10.

  The sealing device 1 has a rotary seal member 8 having a flange 14, and the flange 14 prevents or reduces entry of foreign matter from the atmosphere A side into the device internal space S. The dust strips 38, 40, and 42 further reduce the risk of foreign material intrusion. Therefore, the sealing device 1 is a mud or dusty environment such as a railcar bogie, a sintered pallet bogie, a construction machine, a truck trunnion suspension, an agricultural machine (cultivator, tractor, rice transplanter, etc.). Even in the equipment used in the above, the sealing function is suitably exhibited. However, the application of the sealing device 1 is not limited to such a device, and may be another device.

  As for the device having the sealing device 1, it may be necessary to replenish the device internal space S with a lubricant. At the time of replenishment, care should be taken so that the pressure in the device internal space S does not become too high due to the injection of the lubricant. Therefore, in the sealing device 1, the fixed seal member 10 is provided with at least one slit 50 through which the lubricant can flow out from the device internal space S to the atmosphere A side.

  In this embodiment, the slit 50 is provided in a portion corresponding to the elastic ring 28 in the outer flange 23 of the fixed seal member 10. The slit 50 may be formed by cutting, for example.

  A through-hole 52 through which the lubricant passes from the slit 50 is formed in the reinforcing ring 30 of the fixed seal member 10 at a position overlapping the slit 50. However, in this embodiment, the inner peripheral surface of the through hole 52 is covered with the material of the elastic ring 28. When the pressure in the device internal space S exceeds a certain value, the slit 50 is opened, and the lubricant passes from the device internal space S through the slit 50 and the through hole 52.

  The lubricant that has passed through the slit 50 and the through-hole 52 flows as shown by the arrows in FIG. 1 and presses the dust lip 42 of the rotary seal member 8 toward the atmosphere A, whereby the dust lip 42 and the fixed seal member are pressed. 10 flows out to the atmosphere A side through the gap formed between the two.

  The role of the slit 50 is to allow the lubricant to flow out from the device internal space S to the atmosphere A side. On the other hand, since the role of the sealing device 1 is to keep the lubricant sealed in the device internal space S, it is desirable that the replenished lubricant is held in the device internal space S over a long period of time. When the pressure in the device internal space S exceeds a certain value, the slit 50 expands due to the pressure, allowing the lubricant to pass through the slit 50 from the device internal space S, and closing and lubricating in other cases. It functions as a valve that prevents the agent from passing through.

  Therefore, even if an excessive replenishment force is applied at the time of replenishment of the lubricant, an increase in the pressure in the device internal space S is suppressed, and unexpected damage to the sealing device 1 is prevented, and also due to the high-pressure lubricant. An increase in rotational torque of the rotating shaft 4 is also suppressed. In addition, after the replenishment, the slit is closed to prevent the lubricant from passing through, so that the lubricant is held in the device internal space S for a long period of time. Further, since the slit 50 is provided in the fixed seal member 10, it is not necessary to increase the size of the sealing device 1, particularly the length in the axial direction, in order to provide a special lubricant outflow path. Furthermore, since the slit 50 as a valve is formed in the sealing device 1, particularly the fixed seal member 10, when the outflow performance or the retention performance of the lubricant is deteriorated, it is troublesome to replace other parts of the device. In addition, the sealing device 1 or the fixed seal member 10 can be easily replaced.

  In this embodiment, the slit 50 is provided in the wall portion of the elastic ring 28 corresponding to the outer flange 23 that contacts the fluid on the device internal space S side without contacting other members of the fixed seal member 10. Yes. Therefore, other members do not slide in the vicinity of the slit 50, and since there is no wear due to sliding, the performance of retaining the lubricant is unlikely to deteriorate.

  In this embodiment, the fixed seal member 10 has a double structure of an elastic ring 28 and a reinforcing ring 30, and the rigidity is enhanced by the reinforcing ring 28. When the slit 50 is formed in the elastic ring 30 and the through hole 52 is formed at a position overlapping the slit 50 of the reinforcing ring 28, the slit 50 and the penetrating through the device internal space S when the pressure in the device internal space S exceeds a certain value. The lubricant passes through the holes 52. Since it is not necessary to provide the reinforcing ring 30 with through holes or other parts that weaken the rigidity at other places, a decrease in the rigidity of the reinforcing ring 30 and thus the fixed seal member 10 is minimized.

  The number of slits 50 is not limited. A single slit 50 may be provided in the fixed seal member 10.

  FIG. 4 is an end view of the fixed seal member 10. As shown in FIG. 4, a plurality of slits 50 may be provided in the fixed seal member 10.

  When a plurality of slits 50 are provided in the fixed seal member 10, as shown in FIG. 4, it is preferable that these slits 50 have the same dimensions as each other and are equiangularly spaced from each other. As a result, not only the sealing device 1 can be easily manufactured, but also when the pressure in the device internal space S exceeds a certain value when the lubricant is replenished, the lubricant flows out through these slits 50 at a substantially uniform flow rate. . Therefore, the load on the portion (in this embodiment, the dust lip portion 42) downstream of the slit 50 in the lubricant outflow path is equalized.

  Each slit 50 in FIG. 4 has one linear shape, but a cross-shaped slit 54 can also be used as shown in FIG. Alternatively, other shaped slits may be used. The length of the slits 50 and 54, that is, the size (the size when viewed as shown in FIGS. 4 and 5) is not limited.

  In the sealing device 1, the flange 14 of the rotary seal member 8 repels intrusion of foreign matter from the atmosphere A side into the device internal space S. Further, the dust lip portion 42 of the rotary seal member 8 and the dust lip portions 38 and 40 of the fixed seal member 10 more reliably prevent foreign matters from entering the device internal space S from the atmosphere A side. As described above, the slit 50 provided in the fixed seal member 10 causes the lubricant to flow out when the pressure in the device internal space S exceeds a certain value, so that the gap between the rotary seal member 8 and the fixed seal member 10 is reduced. It is not necessary to reduce the sealing performance (provided by the seal lip portion 36 and the dust lip portions 38, 40, 42) due to the outflow of the lubricant, and the sealing performance to the lubricant by the seal lip portion 36 and the dust lip. The sealing lip portion 36 and the dust lip portions 38, 40, 42 can be firmly formed so as to enhance the sealing performance against mud and dust by the portions 38, 40, 42.

Modification of First Embodiment FIG. 6 shows a sealing device 61 according to a modification of the first embodiment of the present invention. In the drawings subsequent to FIG. 6, the same reference numerals are used to indicate the same components as those in the first embodiment, and the components will not be described in detail.

  In the sealing device 1 shown in FIG. 1, the slit 50 is formed perpendicular to the wall portion provided with the slit 50, but in the sealing device 61 shown in FIG. 6, the slit 50 is provided with the slit 50. It is formed obliquely with respect to the wall portion formed. Since the slit 50 is inclined with respect to the wall portion in this way, the length of the portions on both sides of the slit 50 (the length when viewed as shown in FIG. 6) is increased, and the pressure in the device internal space S is increased. When it is lowered, the slit 50 is likely to be blocked by the restoring force of the material of the elastic ring 28. Therefore, the sealing performance of the lubricant by the fixed seal member 10 can be enhanced.

  FIG. 7 shows a sealing device 62 according to another modification of the first embodiment. In the sealing device 62, a part 55 of the outer flange 23 of the fixed seal member 10 corresponding to the elastic ring 28 is formed thick, and a slit 50 is formed in the thick part 55. ing. The illustrated slit 50 has a cross-sectional shape having two straight lines perpendicular to each other, but the cross-sectional shape of the slit 50 is not limited to the illustrated shape.

  Since the slit 50 is formed in the thick part 55 in this way, the length of the portions on both sides of the slit 50 (the length when viewed as shown in FIG. 6) is increased, and the device internal space S When the pressure is reduced, the slit 50 is likely to be blocked by the restoring force of the material of the elastic ring 28. Therefore, the sealing performance of the lubricant by the fixed seal member 10 can be enhanced.

  FIG. 8 shows a sealing device 63 according to still another modification of the first embodiment. In the sealing device 63, a through hole 56 is formed in a portion corresponding to the elastic ring 28 in the outer flange 23 of the fixed seal member 10. The through hole 56 communicates with a through hole 52 formed in the reinforcing ring 30. A seal piece 58 is tightly fitted in the through hole 56. A slit 50 is formed in the seal piece 58. The material of the seal piece 58 may be the same material as the fixed seal member 10 or a different material, but is an elastic body, for example, an elastomer.

  As described above, the slit 50 is formed in the seal piece 58 that can be separated from the fixed seal member 10. Therefore, when the seal piece 58 deteriorates due to the slit 50 repeatedly expanding and closing due to fluid pressure fluctuations, it is possible to replace only the seal piece 58 and restore the initial performance of the sealing device 63. is there.

  The shapes and dimensions of the through hole 56 and the seal piece 58 are set so that the seal piece 58 does not move to the atmosphere A side through the through hole 52 even if the pressure in the device internal space S increases. For example, when these shapes are circular, the diameters of the through hole 56 and the seal piece 58 are larger than the diameter of the through hole 52. Therefore, even if the pressure in the device internal space S increases, the seal piece 58 remains in a fixed position, and there is no situation where a large amount of fluid suddenly flows out from the device internal space S to the atmosphere A side.

  FIG. 9 shows a sealing device 64 according to still another modification of the first embodiment. FIG. 10 is an end view of the fixed sealing member 10 of the sealing device 64. As shown in these drawings, in the sealing device 64, a thick portion 59 is formed in a portion corresponding to the elastic ring 28 in the outer flange 23 of the fixed seal member 10. As shown in FIG. 10, the thick portion 59 is formed near both ends of the slit 50. Therefore, even if the slit 50 repeatedly expands and closes due to fluid pressure fluctuation, the occurrence of cracks in other portions is reduced. Accordingly, it is possible to suppress a decrease in the life of the elastic ring 28.

  These modifications described with reference to FIGS. 6 to 10 may be combined as long as there is no contradiction.

Second Embodiment FIG. 11 is a diagram according to a second embodiment of the present invention, and shows a sealing device 71 used in a device having two members that rotate relative to each other.

  The sealing device 71 seals a space between the inner ring (inner member) 74 of the rolling bearing and the inner surface of the shaft hole 76 of the housing (outer member) in which the inner ring 74 is inserted. This prevents or reduces the leakage of fluid from S to the atmosphere A side. The inner ring 74 has a cylindrical shape, the shaft hole 76 has a circular cross section, and the sealing device 71 has a substantially annular shape, but only the left side portion thereof is shown in FIG.

  The sealing device 71 includes a rotary seal member (second seal member) 78 called a slinger that is fixed to the inner ring 74 and rotates integrally with the inner ring 74, and a fixed seal member (first seal member) fixed to the shaft hole. ) 80 is an assembly. The rotary seal member 78 and the fixed seal member 80 cooperate to seal the lubricant in the device internal space S. The rotary seal member 78 is fitted to the fixed seal member 80, and when a large force is applied along the axial direction of the sealing device 71, the fitting is released and can be removed.

  The rotary seal member 78 includes a sleeve 82 fixed to the inner ring 74, and a flange 84 that is integrally connected to the end of the sleeve 82 on the atmosphere A side and radially spreads outside thereof. The method of fixing the inner ring 74 and the sleeve 82 is not limited, but may be an interference fit, for example. The rotary seal member 78 has a double structure, and includes an elastic ring 86 made of an elastic body, for example, an elastomer, and a rigid body, for example, a metal reinforcing ring 88, which is in close contact with the elastic ring 86 and reinforces the elastic ring 86. .

  The sleeve 82 includes an inner cylindrical portion 86a that is a part of the elastic ring 86 and is in close contact with the inner ring 74, and an outer cylindrical portion 88a that is a part of the reinforcing ring 88 and is fixed to the outer periphery of the inner cylindrical portion 86a. Have. The flange 84 is a part of the elastic ring 86 and is disposed on the atmosphere A side. The flange 84 is a part of the reinforcing ring 88 and is disposed on the equipment internal space S side and is fixed to the elastic flange part 86b. And a rigid flange portion 88b.

  The fixed seal member 80 includes an outer annular body 92 and an inner annular body 94 arranged coaxially with the outer annular body 92 on the radially inner side of the outer annular body 92. The outer annular body 92 and the inner annular body 94 are connected by a flange 93 on the atmosphere A side.

  The fixed seal member 80 also has a double structure, and has an elastic ring 98 made of an elastic body, for example, an elastomer, and a rigid body that reinforces the elastic ring 98, for example, a metal reinforcing ring 100. A part of the reinforcing ring 100 is embedded in the elastic ring 98 and is in close contact with the elastic ring 98.

  The outer annular body 92 of the fixed seal member 80 is an outer seal portion that is fixed to the shaft hole 76. The fixing method is not limited, but may be an interference fit, for example. The reinforcing ring 100 applies a force toward the radially inner side to the elastic ring 98.

  The elastic ring 98 of the fixed seal member 80 has lip portions 106, 108 and 110. The lip portions 106 and 108 extend obliquely from the inner annular body 94 to the atmosphere A side and radially inward. When the rotary seal member 78 rotates with the inner ring 74, the outer peripheral surface of the sleeve 82 slides with respect to the lip portions 106 and 108. The reinforcing ring 100 gives the lip portions 106 and 108 a force for pressing the lip portions 106 and 108 against the inner ring 74.

  The lip portion 110 extends from the inner flange 94 to the atmosphere A side and is bent. The tip of the lip portion 110 contacts the rigid flange portion 88 b of the flange 84 of the rotary seal member 78, and when the rotary seal member 78 rotates with the inner ring 74, the rigid flange portion 88 b slides relative to the lip portion 110.

  The rotary seal member 78 further includes a dust lip 112 extending radially outward from the outer edge of the flange 84. The dust lip 112 extends obliquely from the outer edge of the flange 84 to the atmosphere A side and radially outward. The tip of the dust lip 112 is in sealing contact with the inner peripheral surface of the shaft hole 76, and when the rotary seal member 78 rotates with the inner ring 74, the dust lip 112 slides against the inner peripheral surface of the shaft hole 76. .

  The lip portions 106, 108, 110, and 112 mainly play a role of preventing entry of foreign matters (mud and dust) from the atmosphere A side to the device internal space S side. However, the lip portions 106, 108, 110, 112 may prevent the lubricant from flowing out from the device internal space S side to the atmosphere A side.

  The sealing device 71 has a rotary seal member 78 having a flange 84, and the flange 84 prevents or reduces entry of foreign matter from the atmosphere A side into the device internal space S. The lip portions 108, 110, and 112 further reduce the possibility of foreign matter intrusion. Therefore, the sealing device 71 suitably exhibits a sealing function even in an apparatus used in a mud or dusty environment such as a pallet of a sintered pallet. However, the application of the sealing device 71 is not limited to such a device, and may be another device.

  The fixed seal member 80 is provided with at least one slit 120 through which the lubricant can flow out from the device internal space S to the atmosphere A side. In this embodiment, the slit 120 is provided in a portion corresponding to the elastic ring 98 in the flange 93 of the fixed seal member 80. The slit 120 may be formed by cutting, for example.

  A through hole 122 through which the lubricant passes from the slit 120 is formed in the reinforcing ring 100 of the fixed seal member 80 at a position overlapping the slit 120. However, in this embodiment, the inner peripheral surface of the through hole 122 is covered with the material of the elastic ring 98. When the pressure in the device internal space S exceeds a certain value, the slit 120 opens, and the lubricant passes from the device internal space S through the slit 120 and the through hole 122.

  The lubricant that has passed through the slit 120 and the through-hole 122 flows as shown by the arrows in FIG. 11, and presses the dust lip 112 of the rotary seal member 78 toward the atmosphere A, whereby the dust lip 112 and the shaft hole 76 are pressed. It flows out to the atmosphere A side through a gap formed between the inner peripheral surfaces.

  When the pressure in the device internal space S exceeds a certain value, the slit 120 expands due to the pressure, allows the lubricant to pass from the device internal space S through the slit 120, and closes and lubricates in other cases. It functions as a valve that prevents the agent from passing through. Therefore, even if an excessive replenishment force is applied at the time of replenishment of the lubricant, an increase in the pressure in the device internal space S is suppressed, and unexpected damage to the sealing device 71 is prevented, and also due to the high-pressure lubricant. An increase in rotational torque of the inner ring 74 is also suppressed. In addition, after the replenishment, the slit is closed to prevent the lubricant from passing through, so that the lubricant is held in the device internal space S for a long period of time. Further, since the slit 120 is provided in the fixed seal member 80, it is not necessary to increase the size of the sealing device 71, particularly the length in the axial direction, in order to provide a special lubricant outflow path. Further, since the slit 120 as a valve is formed in the sealing device 71, in particular, the fixed seal member 80, when the outflow performance or the retention performance of the lubricant is deteriorated, it is troublesome to replace other parts of the device. In addition, the sealing device 71 or the fixed seal member 80 can be easily replaced.

  In this embodiment, the slit 120 is provided in the wall portion of the elastic ring 98 corresponding to the flange 93 that contacts the fluid on the device internal space S side without contacting the other members of the fixed seal member 80. . Therefore, other members do not slide in the vicinity of the slit 120, and since there is no wear due to sliding, the performance of retaining the lubricant is unlikely to deteriorate.

  In this embodiment, the fixed seal member 80 has a double structure of the elastic ring 98 and the reinforcing ring 100, and the rigidity is enhanced by the reinforcing ring 98. When the slit 120 is formed in the elastic ring 100 and the through hole 122 is formed at a position overlapping the slit 120 of the reinforcing ring 98, when the pressure in the device internal space S exceeds a certain value, the slit 120 and the through hole are formed from the device internal space S. The lubricant passes through the holes 122. Since it is not necessary to provide the reinforcing ring 100 with through-holes or other locations that weaken the rigidity at other locations, a decrease in the rigidity of the reinforcing ring 100 and hence the fixed seal member 80 is minimized.

  The number of slits 120 is not limited. A single slit 120 may be provided in the fixed seal member 80. Similar to the slits of FIGS. 4 and 5 of the first embodiment, a plurality of slits 120 may be provided in the fixed seal member 80.

  In this sealing device 71, the flange 84 of the rotary seal member 78 repels the entry of foreign matter from the atmosphere A side into the device internal space S. Further, the dust lip portion 112 of the rotary seal member 78 and the lip portions 108 and 110 of the fixed seal member 80 more reliably prevent foreign matter from entering the device internal space S from the atmosphere A side. As described above, since the slit 120 provided in the fixed seal member 80 causes the lubricant to flow out when the pressure in the device internal space S exceeds a certain value, the slit 120 between the rotary seal member 78 and the fixed seal member 80. It is not necessary to reduce the sealing performance (provided by the lip portions 106, 108, 110, 112) due to the outflow of the lubricant, the sealing performance to the lubricant by the lip portions 106, 108, 110, 112 and mud In addition, the lip portions 106, 108, 110, and 112 can be firmly formed so as to enhance the sealing performance against dust.

  Although the embodiment of the present invention has been described above, the above description is not intended to limit the present invention, and various modifications including deletion, addition, and replacement of components are conceivable within the technical scope of the present invention. .

  The several embodiments and variations described above may be combined as long as they are not contradictory. For example, the modification described above with respect to the first embodiment with reference to FIGS. 6 to 10 can be applied to the second embodiment.

  Further, the shape and number of the lip portions of the fixed seal members 10 and 80 are not limited to those described above.

  The flanges 14 and 84 of the rotary seal members 8 and 78 are not necessarily essential and may be omitted. In this case, the lip portions 40 and 110 of the fixed seal members 10 and 80 are also unnecessary and may be omitted.

  Furthermore, the rotary seal members 8 and 78 may be omitted, and the fixed seal members 10 and 80 may contact the shaft 4 or the inner ring 74.

  In the first embodiment, the shaft 4 is a rotating shaft, and the housing having the shaft hole 6 is a stationary member. In the second embodiment, the inner ring 74 is a rotating body, and the housing having the shaft hole 76 is a stationary member. is there. However, the present invention is not limited to the above embodiment, and can be applied to sealing between two members that rotate relative to each other. For example, the shaft 4 (and the seal member 8) may be stationary, the housing (and the seal member 10) may rotate around it, and the shaft 4 and the housing may also rotate.

1, 61, 62, 63, 71 Sealing device 4 Rotating shaft (inner member)
6,76 Shaft hole (shaft hole of outer member)
8,78 Rotating seal member (second seal member)
10, 80 Fixed seal member (first seal member)
12, 82 Sleeve 14, 84 Flange 16, 86 Elastic ring 18, 88 Reinforcement ring 16a, 86a Inner cylindrical part 18a, 88a Outer cylindrical part 16b, 86b Elastic flange part 18b, 88b Rigid flange part 22, 92 Outer annular body 23 Outside Flange 24 Intermediate annular body 25 Inner flange 26, 94 Inner annular body 28, 98 Elastic ring 30, 100 Reinforcement ring 32 Garter spring 34 Receiving groove 36 Seal lip part 38, 40 Dustrip part 42 Dustrip part 50, 54, 120 Slit 52, 122 Through-hole 55 Thick part 58 Seal piece 59 Thick part 74 Inner ring of rolling bearing (inner member)
93 Flange 106, 108, 110 Lip part 112 Dustrip part

Claims (5)

A sealing device that seals the lubricant in the internal space of the device to the internal space of the device,
The first member is fixed to the inner surface of the outer member of the two relatively rotating members of the device, and the inner member of the two members rotating relative to each other or the outer peripheral surface of the member fixed to the inner member slides. A sealing member,
The sealing device according to claim 1, wherein a slit that allows the lubricant to pass from the internal space of the device when the pressure in the internal space of the device exceeds a certain value is provided in the first seal member.   The sealing device according to claim 1, wherein the slit is provided in a wall portion that does not contact other members of the first seal member. The first seal member includes an elastic ring formed of an elastic body that is in close contact with the outer member, and a reinforcing ring formed of a rigid body that reinforces the elastic ring,
The slit is formed in the elastic ring,
The sealing device according to claim 1, wherein a through-hole through which the lubricant passes from the slit is formed at a position overlapping the slit of the reinforcing ring.   The said 1st sealing member WHEREIN: The said several slit of the same dimension mutually is arrange | positioned at equiangular intervals around the said inner member, The any one of Claim 1 to 3 characterized by the above-mentioned. A sealing device according to claim 1. A second seal member having a sleeve fixed to the inner member, and a flange that is integrally connected to an end portion on the atmosphere side of the sleeve and radially spreads outside the sleeve;
The first seal member includes a lip portion on which an outer peripheral surface of the sleeve slides, and an outer annular body fixed to the inner surface of the outer member,
The second seal member further includes a dust lip that extends radially outward from an outer edge of the flange and slides with respect to an inner peripheral surface of the outer annular body of the first seal member. The sealing device according to any one of claims 1 to 4.

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