JP2020079634A - Seal device - Google Patents

Abstract

To provide a seal device which extends its longevity even when there is a negative pressure in a housing.SOLUTION: The seal device includes a cylindrical sleeve mounted to the outer peripheral face of a rotary shaft arranged in the housing, a slinger having an annular flange expanding from the sleeve to the radial outside, and a fixed seal member mounted to the housing for contacting the slinger, the fixed seal member having an annular main lip formed from an elastic material for slidably contacting the flange of the slinger to seal lubricating oil in the housing, and an annular dust lip formed from an elastic material for slidably contacting the outer peripheral face of the sleeve of the slinger. A reinforcing ring which can contact the inner peripheral face of the dust lip for reinforcing the dust lip is arranged in a clearance between the fixed seal member and the sleeve and mounted to at least either the fixed seal member or the sleeve.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a sealing device.

  For example, an engine of an automobile is provided with an oil seal (sealing device) which is arranged around a crankshaft (rotating shaft) and seals lubricating oil in the crankcase. One type of sealing device for an engine has a rotary seal member called a slinger attached to a crankshaft and a fixed seal member attached to a crankcase. The slinger has a cylindrical sleeve attached to the outer peripheral surface of the crankshaft and an annular flange that extends radially outward from the sleeve. The stationary seal member has a main lip and a dust lip that slidably contact the slinger. The main lip contacts the flange, and the dust lip contacts the outer peripheral surface of the sleeve (Patent Document 1).

JP, 2008-91372, A

  Depending on the engine, the inside of the crankcase may have negative pressure. In this case, a gap is created between the main lip arranged on the lubricating oil side and the flange, and the dust lip arranged on the atmosphere side is sucked to a negative pressure and comes into contact with the sleeve with a strong pressure. Even when strong pressure is applied to such dust lip, it is desirable that the sealing device has a long life.

  Therefore, the present invention provides a sealing device that has a long life even if the inside of the housing has a negative pressure.

  A sealing device according to an aspect of the present invention includes a cylindrical sleeve attached to an outer peripheral surface of a rotating shaft disposed in a housing, a slinger having an annular flange extending radially outward from the sleeve, and the housing. A fixed seal member attached to the slinger and contacting the slinger. The stationary seal member slidably contacts the flange of the slinger and seals the lubricating oil in the housing, and has an annular main lip formed of an elastic material and an outer circumference of the sleeve of the slinger. An annular dust lip formed of an elastic material in slidable contact with the surface. A reinforcing ring capable of contacting the inner peripheral surface of the dust lip and reinforcing the dust lip is disposed in a gap between the fixed seal member and the sleeve, and is attached to at least one of the fixed seal member and the sleeve. Has been.

  In this aspect, a stiffening ring located in the gap between the stationary seal member and the sleeve stiffens the dust lip. Specifically, the reinforcing ring contacts the inner peripheral surface of the dust lip that faces the outer peripheral surface of the sleeve, supports the dust lip sucked by the negative pressure, and excessively deforms the dust lip, and thus the excess dust lip. Since the abrasion is suppressed, even if the inside of the housing has a negative pressure, the life of the sealing device can be long. Further, even if the dust lip is worn, since the reinforcing ring is arranged in the gap between the fixed seal member and the sleeve, even if there is a gap between the reinforcing ring and the sleeve or the fixed seal member, the foreign matter is Less likely to reach the main lip through the gap.

It is a fragmentary sectional view showing the closure concerning a 1st embodiment of the present invention at the time of use. FIG. 3 is an enlarged partial sectional view of the sealing device of FIG. 1 when used. It is a front view which shows the reinforcement ring of the sealing device of FIG. FIG. 4 is a front view of the reinforcing ring of FIG. 3 expanded and contracted. It is a perspective view which shows the both ends of the reinforcement ring of a modification. It is an expanded partial sectional view of the sealing device which concerns on 2nd Embodiment of this invention at the time of use. It is a front view which shows the reinforcement ring of the sealing device of FIG. It is an expanded partial sectional view of the sealing device which concerns on the modification of 2nd Embodiment at the time of use.

  Various embodiments according to the present invention will be described below with reference to the accompanying drawings.

  A sealing device according to an embodiment of the present invention is an oil seal that is arranged around a crankshaft and seals lubricating oil in a crankcase.

First Embodiment As shown in FIG. 1, a sealing device 1 seals a gap between a crankcase (housing) 2 and a crankshaft (rotary shaft) 4 arranged in the crankcase 2, and Prevent leakage of lubricating oil in 2. Although the sealing device 1 has an annular shape centered on the rotation axis Ax of the crankshaft 4, only the upper portion of the sealing device 1 is shown in FIG. 1.

  The sealing device 1 has a slinger 6 and a fixed seal member 8. The slinger 6 is a rotary seal member attached to the crankshaft 4. The fixed seal member 8 is a stationary member attached to the crankcase 2.

  The slinger 6 is made of a rigid material such as metal. The slinger 6 has a cylindrical sleeve 10 and an annular flange 12. The sleeve 10 is attached to the outer peripheral surface of the crankshaft 4 by, for example, interference fit. The flange 12 extends radially outward from the end of the sleeve 10 on the lubricating oil side. Since the slinger 6 is attached to the crankshaft 4, the slinger 6 rotates about the rotation axis Ax together with the crankshaft 4.

  The stationary seal member 8 has a double structure including an elastic ring 14 made of an elastic material, for example, an elastomer, and a rigid material for reinforcing the elastic ring 14, for example, a single rigid ring 16 made of metal. A part of the rigid ring 16 is embedded in the elastic ring 14 and is in close contact with the elastic ring 14.

  The rigid ring 16 has a circular ring portion 16a arranged on the outer side and a circular plate portion 16b which extends from the end of the circular ring portion on the atmosphere side to the inside in the radial direction and is curved. The annular portion 16a and the disc portion 16b are integrally formed.

  The elastic ring 14 has an annular portion 14a, a disc portion 14b, a block portion 14c, a main lip 18, a dust lip 20, and an intermediate lip 22. The annular portion 14a, the disc portion 14b, the block portion 14c, the main lip 18, the dust lip 20, and the intermediate lip 22 are integrally formed. The annular portion 14a is fixed to the outer peripheral surface of the annular portion 16a of the rigid ring 16, and the disc portion 14b is fixed to the atmosphere side surface of the circular disc portion 16b of the rigid ring 16. The block portion 14c is an annular portion that is arranged inside the disc portion 14b in the radial direction and is fixed to the inner end of the disc portion 16b so as to cover the inner end.

  The circular ring portion 14 a of the elastic ring 14 and the circular ring portion 16 a of the rigid ring 16 form a mounting portion mounted on the crankcase 2. Specifically, the annular portions 14a and 16a are attached to the shaft hole of the crankcase 2 by, for example, an interference fit. However, only the annular portion 14a may be tightly fitted in the shaft hole of the crankcase 2, or only the annular portion 16a may be tightly fitted in the shaft hole of the crankcase 2.

  The main lip 18 is an annular ring that extends obliquely outward from the block portion 14 c toward the lubricating oil side, slidably contacts the atmosphere-side surface 12 a of the flange 12 of the slinger 6, and the inside of the crankcase 2 Seal the lubricating oil.

  The dust lip 20 is a circular ring extending obliquely inward from the block portion 14c toward the atmosphere side, and slidably contacts the outer peripheral surface of the sleeve 10 of the slinger 6. The dust lip 20 blocks foreign matter (for example, water and dust) from flowing from the atmosphere side to the lubricating oil side.

  The intermediate lip 22 is an annular ring extending from the block portion 14c to the lubricating oil side. Lubricating oil may pass through the main lip 18 from the lubricating oil side and enter the space 24 defined by the main lip 18, dust lip 20, sleeve 10 and flange 12. The intermediate lip 22 collects oil drops existing in the space 24. Specifically, the oil droplets splashed by the rotation of the slinger 6 adhere to the inner surface 18 a of the main lip 18. Since the fixed seal member 8, and by extension, the main lip 18 and the intermediate lip 22 are stationary, the oil droplets adhering to the inner surface 18a of the main lip 18 above the rotation axis Ax of the crankshaft 4 will not reach the outer peripheral surface of the intermediate lip 22. 22a. The oil droplets received on the outer peripheral surface 22a of the intermediate lip 22 fall on the inner surface 18a of the main lip 18 below the rotation axis Ax. Below the rotation axis Ax of the crankshaft 4, the oil droplets adhering to the inner surface 18a of the main lip 18 are splashed by the rotation of the slinger 6 and returned to the space on the lubricating oil side. The illustrated intermediate lip 22 extends parallel to the rotation axis Ax, but may be inclined or curved with respect to the rotation axis Ax. The illustrated intermediate lip 22 is not in contact with the slinger 6, but may be in contact therewith.

  The sealing device 1 further includes a reinforcing ring 30 that reinforces the dust lip 20. The reinforcing ring 30 is arranged in the gap 32 between the block portion 14c of the fixed seal member 8 and the sleeve 10 of the slinger 6.

  As shown in FIG. 2, the reinforcing ring 30 is attached to the inside of the elastic ring 14 of the fixed seal member 8 by an interference fit. The reinforcing ring 30 has a pentagonal cross section, the inner peripheral surface 30a has a cylindrical shape, and the outer peripheral surface has a cylindrical surface 30b and an inclined truncated cone-shaped surface 30c. An annular gap 34 is provided between the inner peripheral surface of the reinforcing ring 30 and the outer peripheral surface of the sleeve 10. The cylindrical surface 30b of the outer peripheral surface of the reinforcing ring 30 and the inclined truncated cone-shaped surface 30c always contact the inner peripheral surface of the elastic ring 14. In particular, the inclined frustoconical surface 30c always contacts the inner peripheral surface of the base of the dust lip 20.

  Preferably, the reinforcing ring 30 is formed of a material having higher rigidity than the elastic material that is the material of the elastic ring 14, for example, a resin material such as polyamide or polytetrafluoroethylene (PTFE). The stiffening ring 30 is attached to the stationary seal member 8 which is always stationary and does not contact the rotating slinger 6, so it can be made of a material selected from a wide variety of materials.

  Preferably, as shown in FIGS. 3 and 4, the stiffening ring 30 is formed from an elongated curved stretchable rod having two ends 30D, 30E. FIG. 3 shows the reduced reinforcing ring 30 with the ends 30D, 30E butted against it. The left side of FIG. 4 shows the stretched reinforcement ring 30 with the ends 30D, 30E spaced apart. The right side of FIG. 4 shows a reduced reinforcing ring 30 with the ends 30D, 30E superimposed.

  By contracting the reinforcing ring 30, the reinforcing ring 30 can be easily disposed at a position between the dust lip 20 and the intermediate lip 22, as shown in FIG. After deployment, the reinforcement ring 30 expands due to its stretchability, becomes circular as shown in FIG. 3, and is surrounded by the stationary seal member 8 to be fixed in that position. In this way, the reinforcing ring 30 can be easily attached to the fixed seal member 8 arranged outside the slinger 6.

  The reinforcing ring 30 shown in FIG. 3 and FIG. 4 is a straight cut type, and the end faces of the end portions 30D and 30E respectively match the planes including the axis of the reinforcing ring 30. However, the special step cut type reinforcing ring 30 shown in FIG. 5 may be used. When the special step cut type reinforcing ring 30 is arranged at a fixed position of the fixed seal member 8, the radially extending projection 31A formed at the end portion 30D is fitted into the radially extending recess portion 32B formed at the end portion 30E. That is, the radially extending projection 31B formed on the end portion 30E fits into the radially extending recess portion 32A formed on the end portion 30D. Similar to the reinforcing ring 30 shown in FIGS. 3 and 4, this reinforcing ring 30 can also be easily attached to the fixed seal member 8 arranged outside the slinger 6.

  However, the reinforcing ring 30 may be a stretchable endless ring.

  Depending on the engine, the inside of the crankcase 2 may have a negative pressure. In this case, a flow of air can occur as indicated by the arrow in FIG. A gap is created between the main lip 18 arranged on the lubricating oil side and the flange 12 of the slinger 6, an air flow is generated in the space 24 as indicated by an arrow, and the dust lip 20 arranged on the atmosphere side has a negative pressure. And is brought into contact with the sleeve 10 of the slinger 6 with a strong pressure. In such a case, the dust lip 20 may be worn in a short time.

  In this embodiment, a stiffening ring 30 located in the gap 32 between the stationary seal member 8 and the sleeve 10 stiffens the dust lip 20. Specifically, the reinforcing ring 30 is always in contact with the inner peripheral surface of the base portion of the dust lip 20 facing the outer peripheral surface of the sleeve 10. Therefore, the reinforcing ring 30 supports the dust lip 20 sucked by the negative pressure and suppresses the excessive deformation of the dust lip 20 and the excessive wear of the dust lip 20, so that the inside of the crankcase 2 is exposed to the negative pressure. Even if there is, the life of the sealing device 1 can be secured for a long time.

  Further, even if the dust lip 20 is worn, the reinforcing ring 30 is arranged in the gap 32 between the fixed seal member 8 and the sleeve 10, so that a gap 34 exists between the reinforcing ring 30 and the sleeve 10. It is unlikely that foreign matter will reach the main lip 18 through the gap 34.

  Since the reinforcing ring 30 is attached to the inside of the fixed seal member 8 by an interference fit and does not slide with respect to the dust lip 20, the reinforcing ring 30 does not damage the dust lip 20.

  The stiffening ring 30 is attached to the stationary seal member 8 which is always stationary and does not contact the rotating slinger 6, so it can be made of a material selected from a wide variety of materials. By forming the reinforcing ring 30 from a material having higher rigidity than the elastic material that is the material of the elastic ring 14, the reinforcing ring 30 can firmly support the dust lip 20. Further, the reinforcing ring 30 has a long life because it does not slide on any part and is less likely to be worn.

  However, the reinforcing ring 30 may be arranged so that the sleeve 10 of the slinger 6 slides on a part or all of the inner peripheral surface of the reinforcing ring 30. In this case, at least the inner peripheral surface 30a of the reinforcing ring 30 is preferably formed of a resin material having a small friction coefficient such as PTFE, polyether ether ketone (PEEK), and polyphenylene sulfide (PPS).

Second Embodiment FIG. 6 is an enlarged partial sectional view of the sealing device 40 according to the second embodiment of the present invention when in use. In the drawings from FIG. 6 onward, the same reference numerals are used to indicate the components common to the first embodiment, and those components will not be described in detail.

  In this embodiment, the sealing device 40 has, instead of the reinforcing ring 30, a reinforcing ring 42 that reinforces the dust lip 20. The reinforcing ring 42 is arranged in the gap 32 between the block portion 14c of the fixed seal member 8 and the sleeve 10 of the slinger 6.

  The reinforcing ring 42 is attached to the outer peripheral surface of the sleeve 10 by interference fitting. The reinforcing ring 42 has a pentagonal cross section, the inner peripheral surface 42a has a cylindrical shape, and the outer peripheral surface has a cylindrical surface 42b and an inclined truncated cone-shaped surface 42c. There is no gap between the inner peripheral surface of the reinforcing ring 42 and the outer peripheral surface of the sleeve 10 due to the interference fit. The cylindrical surface 42b and the inclined truncated cone-shaped surface 42c of the outer peripheral surface of the reinforcing ring 42 are separated from the fixed seal member 8. That is, an annular gap 44 is provided between the outer peripheral surface of the reinforcing ring 42 and the inner peripheral surface of the fixed seal member 8.

  However, when the inside of the crankcase 2 becomes a negative pressure and an air flow toward the lubricating oil side is generated as shown by an arrow, the dust lip 20 is deformed as shown by an imaginary line, and the base portion of the dust lip 20 is The inner peripheral surface contacts the inclined truncated cone-shaped surface 42c of the outer peripheral surface of the reinforcing ring 42.

  In this embodiment, the reinforcing ring 42 fixed to the slinger 6 rotates with the slinger 6, and the surface 42 c slides with respect to the dust lip 20. Therefore, preferably, at least the surface 42c of the reinforcing ring 42 is formed of a resin material having a small friction coefficient, such as PTFE, PEEK, or PPS. Further, since the reinforcing ring 42 reinforces the dust lip 20, the reinforcing ring 42 is preferably made of a material having higher rigidity than the elastic material which is the material of the elastic ring 14.

  Preferably, as shown in FIG. 7, the reinforcing ring 42 is an endless ring. The reinforcing ring 42 has elasticity, and is suitable for interference fit with the outer peripheral surface of the flange 12 of the slinger 6. By extending the reinforcing ring 42, the reinforcing ring 42 can be easily arranged at a position between the dust lip 20 and the intermediate lip 22, as shown in FIG. 6. After deployment, the stiffening ring 42 is locked in place by contracting due to its stretchability. In this way, the reinforcing ring 42 can be easily attached to the slinger 6.

  In this embodiment, a reinforcing ring 42 arranged in the gap 32 between the stationary seal member 8 and the sleeve 10 reinforces the dust lip 20. A gap 44 is provided between the reinforcing ring 42 and the fixed seal member 8, but when sucked by negative pressure, the inner peripheral surface of the dust lip 20 contacts the reinforcing ring 42 and is reinforced by the reinforcing ring 42. It The reinforcing ring 42 contacts the inner peripheral surface of the dust lip 20 that faces the outer peripheral surface of the sleeve 10 to support the dust lip 20 that is sucked by the negative pressure, so that the dust lip 20 is excessively deformed. Since excessive wear is suppressed, the life of the sealing device 40 can be ensured long even if the inside of the crankcase 2 is under negative pressure.

  Further, even if the dust lip 20 is worn, since the reinforcing ring 42 is arranged in the gap 32 between the fixed seal member 8 and the sleeve 10, there is a gap 44 between the reinforcing ring 42 and the fixed seal member 8. Nonetheless, there is little risk that foreign matter will reach the main lip 18 through the gap 44. In particular, the surface 42b of the reinforcing ring 42 does not overlap the outer peripheral surface of the sleeve 10 with which the dust lip 20 is in contact in the axial direction, and thus foreign matter is unlikely to pass through the gap 44.

  A stiffening ring 42 mounted on the outer peripheral surface of the sleeve 10 of the slinger 6 rotates with the slinger 6, while the dust lip 20 remains stationary. Therefore, the reinforcing ring 42 slides with respect to the dust lip 20. However, since the reinforcing ring 42 is an endless ring, damage to the dust lip 20 is small.

  FIG. 8 is an enlarged partial sectional view of the sealing device 40 according to the modification of the second embodiment when it is used. In this modification, a peripheral groove 46 is formed on the outer peripheral surface of the sleeve 10, and the reinforcing ring 42 is fitted in the peripheral groove 46. In this case, since the reinforcing ring 42 is fitted in the circumferential groove 46, it is difficult to move in the axial direction of the sealing device 40. Therefore, even if the inside of the crankcase 2 becomes a negative pressure and the reinforcing ring 42 is sucked by the air flow, the reinforcing ring 42 is maintained in a fixed position.

Other Modifications The embodiments of the present invention have been described above, but the above description does not limit the present invention, and various modifications including deletion, addition, and replacement of constituent elements are within the technical scope of the present invention. Examples are possible.

  For example, at least one spiral (spiral) groove disclosed in JP-A-2018-91372 and JP-A-2014-084934 may be formed on the atmosphere-side surface 12a of the flange 12 of the slinger 6. .. Such a spiral groove plays a role of returning the drop of the lubricating oil that has entered the space 24 from the space 24 to the outside in the radial direction and further to the outside of the main lip 18 according to the rotation of the slinger 6.

  The inner surface 18a of the main lip 18 may be formed with a plurality of screw protrusions disclosed in Japanese Patent No. 6196408. Such screw projections play a role of returning the drops of lubricating oil that have entered the space 24 from the space 24 to the outside in the radial direction and thus to the outside of the main lip 18 in accordance with the rotation of the slinger 6.

  A plurality of protrusions for suppressing excessive deformation of the dust lip 20 disclosed in Japanese Patent Laid-Open No. 2014-084934 may be formed on the inner peripheral surface of the dust lip 20. When the inside of the space 24 becomes a negative pressure, such a projection temporarily contacts the outer peripheral surface of the sleeve 10 of the slinger 6 and temporarily creates a gap between the tip of the dust lip 20 and the outer peripheral surface of the sleeve 10. Cause to.

  The sealing device according to the above embodiment is an oil seal that is arranged around the crankshaft and seals the lubricating oil in the crankcase. However, the present invention is not limited to the embodiment, and for example, an oil seal arranged around the shaft of the transmission to seal lubricating oil in the housing of the transmission, and arranged around the shaft of the differential gear mechanism. It can also be used as an oil seal that seals the lubricating oil in the housing of the differential gear mechanism and an oil seal that is disposed around the shaft of the motor and seals the lubricating oil in the housing of the motor.

  Aspects of the invention are also described in the numbered clauses below.

Clause 1. A cylindrical sleeve attached to the outer peripheral surface of the rotating shaft arranged in the housing, and a slinger having an annular flange extending radially outward from the sleeve,
A fixed seal member attached to the housing and in contact with the slinger,
The fixed seal member,
An annular main lip formed from an elastic material that slidably contacts the flange of the slinger and seals the lubricating oil in the housing;
An annular dust lip formed of an elastic material that slidably contacts the outer peripheral surface of the sleeve of the slinger,
A reinforcing ring capable of contacting the inner peripheral surface of the dust lip and reinforcing the dust lip is disposed in a gap between the fixed seal member and the sleeve, and is attached to at least one of the fixed seal member and the sleeve. A sealing device characterized by being provided.

Clause 2. The reinforcing ring is attached to the fixed seal member, is constantly in contact with the inner peripheral surface of the dust lip, and a gap is provided between the reinforcing ring and the outer peripheral surface of the sleeve. Sealing device according to clause 1, characterized in that it is formed from an elongated curved elastic rod with two ends.

  In this case, the reinforcing ring is attached to the fixed sealing member by an interference fit and does not slide with respect to the dust lip, so that the reinforcing ring does not damage the dust lip. Since the reinforcing ring is formed from a long curved and stretchable rod having two ends, the reinforcing ring can be easily attached to the fixed seal member arranged outside the slinger.

Clause 3. The reinforcing ring is attached to the outer peripheral surface of the sleeve by an interference fit, and a gap is provided between the reinforcing ring and the fixed seal member, and the reinforcing ring is an endless ring having elasticity. The sealing device according to clause 1.

  In this case, since the reinforcing ring is an endless ring having elasticity, it is possible to easily attach the reinforcing ring to the outer peripheral surface of the slinger. Although a gap is provided between the reinforcing ring and the fixed seal member, when sucked by negative pressure, the inner peripheral surface of the dust lip contacts the reinforcing ring and is reinforced by the reinforcing ring. A stiffening ring attached to the outer surface of the sleeve of the slinger rotates with the slinger while the dust lip remains stationary. Therefore, although the reinforcing ring slides with respect to the dust lip, since the reinforcing ring is an endless ring, damage to the dust lip is small.

Clause 4. The sealing device according to any one of clauses 1 to 3, wherein the reinforcing ring is made of a material having higher rigidity than the elastic material.

  In this case, the reinforcing ring can firmly support the dust lip.

Clause 5. The sealing device according to clause 3, wherein a peripheral groove is formed on the outer peripheral surface of the sleeve, and the reinforcing ring is fitted in the peripheral groove.

  In this case, since the reinforcing ring is fitted in the circumferential groove, it is difficult to move in the axial direction of the sealing device. Therefore, even if the inside of the housing becomes a negative pressure and the reinforcing ring is sucked by the air flow, the reinforcing ring is maintained in a fixed position.

1,40 Sealing device 2 Crank case (housing)
4 Crank shaft (rotating shaft)
6 slinger 8 fixed seal member 10 sleeve 12 flange 18 main lip 20 dust lip 30,42 reinforcing rings 30D, 30E end 32 gap 40 sealing device 46 circumferential groove

Claims (5)

A cylindrical sleeve attached to the outer peripheral surface of the rotating shaft arranged in the housing, and a slinger having an annular flange extending radially outward from the sleeve,
A fixed seal member attached to the housing and in contact with the slinger,
The fixed seal member,
An annular main lip formed from an elastic material that slidably contacts the flange of the slinger and seals the lubricating oil in the housing;
An annular dust lip formed of an elastic material that slidably contacts the outer peripheral surface of the sleeve of the slinger,
A reinforcing ring capable of contacting the inner peripheral surface of the dust lip and reinforcing the dust lip is disposed in a gap between the fixed seal member and the sleeve, and is attached to at least one of the fixed seal member and the sleeve. A sealing device characterized by being provided. The reinforcing ring is attached to the fixed seal member, is constantly in contact with the inner peripheral surface of the dust lip, and a gap is provided between the reinforcing ring and the outer peripheral surface of the sleeve. The sealing device according to claim 1, wherein the sealing device is formed of a long curved elastic rod having two ends. The reinforcing ring is attached to the outer peripheral surface of the sleeve by an interference fit, and a gap is provided between the reinforcing ring and the fixed seal member, and the reinforcing ring is an endless ring having elasticity. The sealing device according to claim 1. The sealing device according to any one of claims 1 to 3, wherein the reinforcing ring is made of a material having higher rigidity than the elastic material. The sealing device according to claim 3, wherein a peripheral groove is formed on the outer peripheral surface of the sleeve, and the reinforcing ring is fitted in the peripheral groove.

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