JP2020183787A - Sealed bearing - Google Patents

Abstract

To provide a sealed bearing which is suppressed in the deformation of an outer ring and an inner ring, favorable in a bearing assembling property, and held in sealing performance even if an external atmosphere is varied to a vacuum environment from an atmosphere environment.SOLUTION: A sealed bearing comprises: an inner ring 12 and an outer ring 13; a plurality of rolling bodies 14 arranged between the inner ring 12 and the outer ring 13; a cage 15 for holding the plurality of rolling bodies 14 along a peripheral direction; and a seal body 16 arranged in an opening part between the inner ring 12 and the outer ring 13. The seal body 16 is a fiber-made annular body, an annular step part 21 is formed at an edge of a face at a side having a raceway surface of one bearing ring out of the inner ring 12 and the outer ring 13, the seal body 16 is assembled to the step part 21, one end of the seal body 16 is fixed by the step part 21 of one bearing ring and the pressing member 22 by an arrangement of the annular pressing member 22 at an end face of one bearing ring, and the other end of the seal body 16 slidably contacts with a face at a side having a raceway surface of the other bearing ring out of the inner ring 12 and the outer ring 13.SELECTED DRAWING: Figure 1

Description

The present invention relates to a sealed bearing provided with a contact-type seal used in an environment where foreign matter such as mud or sand may be mixed, and particularly to a sealed bearing that can be used even if the external atmosphere changes from an atmospheric environment to a vacuum environment.

As a sealed bearing provided with a sealing body that seals the inner space of the bearing between the inner ring and the outer ring, the sealed bearing shown in Patent Document 1 is known. As shown in FIG. 2, the sealed bearing 1a is formed from a filter 6c in which both outer peripheral edges 6b are made of annular rubber in the sealing grooves 2a and 3a formed in the inner ring 2 and the outer ring 3, and the outer peripheral surface has a predetermined mesh. It is a bearing in which the formed cylindrical seal body 6a is arranged. In the sealed bearing 1a, the outer peripheral surface of the sealing body 6a is composed of a filter 6c having a predetermined mesh.

By the way, since the outer peripheral edge 6b of the seal body 6a is made of rubber, it has a followability to the relative displacement between the inner ring and the outer ring due to the elasticity of the rubber, but the rubber is cured by the change of the molecular structure at low temperature or high temperature. And embrittlement and deterioration occur. Therefore, if the external atmosphere fluctuates from the atmospheric environment to the vacuum environment, or if the atmospheric pressure, temperature, or the like fluctuates greatly, the sealing body 6a may deteriorate and the sealing property may not be maintained.

On the other hand, it is conceivable to use a plastically deformable material such as metal as the sealing body and to use a shield plate in which fibers are sandwiched. This shield plate is plastically deformed and fixed to the seal groove for use.

However, when the shield plate is fixed to the seal groove, the shield plate is plastically deformed, so that a force for expanding the seal groove may be applied. In this case, the outer ring and the inner ring are elastically deformed, and as a result, the assembling property of the bearing is deteriorated.

On the other hand, it is conceivable to use the sealed bearing described in Patent Document 2. As shown in FIG. 3A, the sealed bearing 1b is a bearing in which an annular sealing body 6d made of fibers is inserted into an annular groove 3b formed in the outer ring 3. Then, a retaining ring 7 is arranged on the outer surface of the seal body 6d of the sealed bearing 1b, and the seal body 6d is fixed to the outer ring 3.

A retaining ring 7 such as a C ring as shown in FIG. 3 (b) is inserted between the inner ring 2 and the outer ring 3 from the outside as shown in FIG. 3 (c), and as shown in FIG. 3 (a). , It is used by fitting it into the annular groove 3b of the outer ring 3.

JP-A-2002-250354 JP-A-2017-8964

However, as shown in FIG. 3C, the height of the retaining ring 7 is shorter than the width between the inner ring 2 and the outer ring 3, so that when the retaining ring 7 is fitted into the annular groove 3b of the outer ring 3, the inner ring 2 side In the portion of the seal body 6d of the above, there is a portion where the retaining ring 7 is not arranged. In this case, due to fluctuations in the bearing environment or the like, the resin seal body 6d may be deformed outward in the axial direction, and as a result, the sealing property may be deteriorated and foreign matter may enter the space inside the bearing. ..

Further, when the C ring is used as the retaining ring 7, the resin seal body 6d is deformed outward in the axial direction due to fluctuations in the bearing environment or the like even at an opening provided at one location in the circumferential direction of the C ring. There is a risk, and as a result, the sealability may be reduced.

Therefore, the present invention provides a sealed bearing in which deformation of the outer ring and the inner ring is suppressed, the bearing can be incorporated well, and the sealing property is maintained even if the external atmosphere changes from the atmospheric environment to the vacuum environment. The purpose is.

In order to solve the above-mentioned problems, the present invention comprises an inner ring, an outer ring arranged radially outside the inner ring, a plurality of rolling elements arranged between the inner ring and the outer ring, and the plurality of rolling elements. A sealed bearing including a cage that holds a moving body along the circumferential direction and a sealing body that is arranged in an opening between the inner ring and the outer ring and seals the space inside the bearing. , An annular body made of fiber, and an annular step portion is formed on the edge of the surface of one of the inner ring and the outer ring on the side having the raceway surface, and the seal body is incorporated in this step portion. By arranging an annular pressing member on the end surface of the one raceway ring, one end of the seal body is fixed by the step portion of the one raceway ring and the pressing member, and the inner ring and the outer ring are among the inner ring and the outer ring. An attempt is made to solve the above-mentioned problem by characterized in that the other end of the seal body is slidably contacted with the surface of the other raceway ring on the side having the raceway surface.

Further, even if the first reinforcing member is arranged on the surface of the seal body on the rolling element side and a gap is formed between the surface of the other raceway ring on the side having the raceway surface and the first reinforcing member. Good.
Further, a second reinforcing member is arranged on the surface of the seal body opposite to the rolling element side, and a gap is formed between the surface of the other raceway ring having the raceway surface and the second reinforcing member. You may.

Further, the sealed bearing of the present invention can be used in outer space.

The sealed bearing according to the present invention has a step portion on the edge of the raceway surface of a predetermined raceway ring, and an annular pressing member is arranged on the end surface of the raceway ring. When fitting into the portion, it is possible to prevent deformation due to application of force, and the assembling property of the bearing is improved.
Further, when reinforcing members are arranged on the surface of the seal body on the rolling element side or the surface opposite to the rolling element side, these reinforcing members suppress the deformation of the fiber seal body to the outside in the axial direction. Even if the external atmosphere changes from the atmospheric environment to the vacuum environment, the sealing property can be maintained.

Further, when a gap is formed between the first reinforcing member and the second reinforcing member and the surface of the raceway ring on the side where the seal body is slidably in contact with the raceway surface, the surface and the first surface are formed. Contact or sliding with the reinforcing member or the second reinforcing member can be avoided, and it is possible to prevent abnormal noise from being generated or the raceway ring having this surface being damaged to shorten the life of the bearing. Further, when the external atmosphere changes from the atmospheric environment to the vacuum environment, a portion where the inside and the outside of the seal body are communicated with each other via the fiber seal body is formed, and air can flow in and out of the seal body. The deformation outward in the axial direction can be further suppressed.

(A) A partial vertical sectional view showing an example of an embodiment of a sealed bearing according to the present invention, and (b) and a partially enlarged sectional view of (a). Partial longitudinal sectional view showing an example of a conventional sealed bearing. (A) A partial vertical sectional view showing another example of a conventional sealed bearing, (b) a front view showing an example of a retaining ring used in (a), and (c) a state in which the retaining ring is being fitted. Partial vertical cross section.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
As shown in FIG. 1, the sealed bearing 11 according to the present invention has a plurality of rolling elements arranged between the inner ring 12, the outer ring 13 arranged radially outside the inner ring 12, and the inner ring 12 and the outer ring 13. A bearing including a 14 and a cage 15 that holds a plurality of rolling elements 14 along the circumferential direction, and a seal body 16 that is arranged in an opening between the inner ring 12 and the outer ring 13 and seals the inner space of the bearing. Is.

In FIG. 1, the seal body 16 is fixed on the outer ring 13 side, but the seal body 16 may be fixed on the inner ring 12 side. In this specification, the case where the seal body 16 is fixed on the outer ring 13 side will be described. When the seal body 16 is fixed on the inner ring 12 side, the fixing, sliding, and mechanism of the seal body 16 are interpreted by exchanging the inner ring 12 and the outer ring 13 in the present specification.

A raceway surface is formed on the outer peripheral surface of the inner ring 12 and the inner peripheral surface of the outer ring 13, respectively. The raceway surface of the inner ring 12 and the raceway surface of the outer ring 13 are each composed of grooves having an arcuate cross-sectional shape in the radial direction.

Rolling bodies 14 are arranged at intervals along the circumferential direction in the annular space formed between these orbital surfaces. The rolling elements 14 are housed between the arcuate orbital surfaces. The sealed bearing of this embodiment is a ball bearing, and the rolling element 14 has a spherical shape, but the present invention can be applied to bearings other than ball bearings. For example, as the sealed bearing, a roller bearing using a cylindrical rolling element 14 or a conical roller bearing using a conical rolling element 14 may be used. In this case, the shape of the raceway surface also becomes a form corresponding to the type of the rolling element 14.

Further, the cage 15 is arranged between the inner ring 12 and the outer ring 13, and has a predetermined distance along the circumferential direction so as to connect the annular portions located on both sides in the axial direction and the annular portions. It has a plurality of pillars to be arranged. Between the adjacent pillars is a pocket for accommodating the rolling element 14. That is, in the cage 15, a plurality of pocket holes are provided at equal intervals on the peripheral wall of the annular body, and the rolling elements 14 are arranged in the pocket holes.

The inner ring 12 and the outer ring 13 are formed of a metal such as martensitic stainless steel (SUS440C or the like).

Further, as the material constituting the rolling element 14, a metal such as martensitic stainless steel (SUS440C or the like), a ceramic material, or the like can be mentioned.

Examples of the material constituting the cage 15 include metals such as aluminum alloys, titanium alloys, stainless alloys and inconel, and thermoplastic resins such as polyetheretherketone (PEEK), polyphenylene sulfide (PPS) and polyamide (PA). Be done. Further, a sliding resin such as a fluororesin such as polytetrafluoroethylene (PTFE) may be used in combination with these.

At least one of the inner ring 12 and the outer ring 13, that is, the edge of the surface 13a on the side of the outer ring 13 having the raceway surface in FIG. 1, is formed with an annular step portion 21 that is continuous over the entire circumference. Then, an annular pressing member 22 is arranged on the axial end surface of the raceway ring (outer ring 13). By attaching the pressing member 22 to the axial end surface of the raceway ring (outer ring 13), a fixing groove 23 is formed from the step portion side surface 21a, the step portion bottom surface 21b, and the pressing member side surface 22a.
Although the pressing member 22 is not shown, the pressing member 22 is fixed to the outer ring 13 by being pressed from the outside by another member or fixed with a screw or the like.

The seal body 16 is an annular body made of fiber and can be incorporated into the step portion 21. After incorporating the seal body 16 into the step portion 21, the pressing member 22 is attached to form the fixing groove 23, so that one end edge of the seal body 16 is fixed by the fixing groove 23.

Then, the other end surface of the seal body 16 slidably contacts the other raceway ring of the inner ring 12 and the outer ring 13, that is, the surface 12a on the side of the inner ring 12 having the raceway surface in FIG.

The shape of the surface 12a on the side of the inner ring 12 having the raceway surface is not particularly limited, and may have a step portion 24 as shown in FIG. 1, and although not shown, it has a step portion. It does not have to be. As shown in FIG. 1, when the seal body 16 has the step portion 24, not only the other end surface of the seal body 16 is slidably contacted with the step portion bottom portion 24b, but also one of the side surfaces of the surface of the seal body 16 on the rolling element side. Since the portion slidably contacts the side surface 24a of the step portion, the sealing performance can be further improved.

Examples of the fibers constituting the seal body 16 include meta-type total aromatic aramid fibers.

Since the seal body 16 is made of fiber, it has good air permeability, but there is a possibility that the seal body 16 may be deformed outward in the axial direction due to changes in the operating environment of the obtained sealed bearing. In order to prevent this deformation, the first reinforcing member 16a is arranged on the surface of the seal body 16 on the rolling element side, and the second reinforcing member 16b is arranged on the surface of the seal body 16 opposite to the surface on the rolling element side. You may do it. By arranging the first reinforcing member 16a and the second reinforcing member 16b, the above-mentioned deformation and the like can be suppressed.

As shown in FIG. 1A, the ends of the first reinforcing member 16a and the second reinforcing member 16b arranged on one end edge side of the seal body 16 fixed to the fixing groove 23 are stepped portions facing each other. It is preferable to make contact with the side surface 21a and the side surface 22a of the pressing member. By doing so, it is possible to prevent the seal body 16 from bending at the portion protruding from the fixing groove 23 and causing deformation of the seal body 16.

Further, as shown in FIGS. 1A and 1B, a gap may be provided between the first reinforcing member 16a and the second reinforcing member 16b and the surface 12a on the side of the inner ring 12 having the raceway surface. preferable. Specifically, as shown in FIG. 1B, a gap a1 is provided between the first reinforcing member 16a and the surface 12a, and a gap a2 is provided between the second reinforcing member 16b and the surface 12a. Is preferable. By providing the gaps a1 and a2, contact and sliding between the first reinforcing member 16a and the second reinforcing member 16b and the surface 12a are avoided, abnormal noise is generated, and the inner ring 12 is damaged, resulting in bearings. It is possible to prevent the life of the bearing from being shortened. Further, by providing the gaps a1 and a2, a portion where the space inside the bearing and the outside of the bearing are connected only by the fiber seal body 16 is secured, so that even if the external atmosphere fluctuates significantly, air is provided. The movement path of the seal body 16 is secured, the deformation of the seal body 16 in the axial direction can be prevented, and the sealability can be maintained.
The lengths of the gaps a1 and a2 may be long enough to retain the above-mentioned characteristics.

The sealed bearing manufactured by the present invention can be used even if the external atmosphere fluctuates significantly, and can be used in outer space.

Although the embodiments of the present invention have been described above with reference to the drawings, the present invention is not limited to those of the illustrated embodiments. It is possible to make various modifications and modifications to the illustrated embodiment within the same range as the present invention or within the same range.

1a, 1b Sealed bearing 2 Inner ring 3 Outer ring 2a Seal groove 3a Seal groove 3b Circular groove 6a Seal body 6b Outer peripheral edge 6c Filter 6d Seal body 7 Stop ring 11 Sealed bearing 12 Inner ring 12a Surface on the side having the raceway surface of the inner ring 13 Outer ring 13a Surface on the side having the raceway surface of the outer ring 14 Rolling body 15 Cage 16 Seal body 16a First reinforcing member 16b Second reinforcing member 21 Step portion 21a Step portion side surface 21b Step portion bottom surface 22 Pressing member 22a Pressing member side surface 23 Fixing groove 24 Steps 24a Steps Side 24b Steps Bottom a1 Gap a2 Gap

Claims (4)

An inner ring, an outer ring arranged radially outside the inner ring, a plurality of rolling elements arranged between the inner ring and the outer ring, and a cage for holding the plurality of rolling elements along the circumferential direction. A sealed bearing provided with a sealing body arranged in an opening between the inner ring and the outer ring and sealing the space inside the bearing.
The seal body is an annular body made of fiber.
An annular step portion is formed on the edge of the surface of one of the inner ring and the outer ring on the side having the raceway surface, and the seal body is incorporated in this step portion.
By arranging an annular pressing member on the end surface of the one raceway ring, one end of the seal body is fixed by the step portion of the one raceway ring and the pressing member.
A sealed bearing characterized in that the other end of the seal body slidably contacts the surface of the inner ring and the outer ring on the side of the other raceway ring that has a raceway surface. According to claim 1, a first reinforcing member is arranged on a surface of the seal body on the rolling element side, and a gap is formed between the surface of the other raceway ring on the side having the raceway surface and the first reinforcing member. The sealed bearing described. A claim in which a second reinforcing member is arranged on a surface of the seal body opposite to the rolling element side, and a gap is formed between the surface of the other raceway ring having the raceway surface and the second reinforcing member. Item 2. The sealed bearing according to item 2. The sealed bearing according to any one of claims 1 to 3, which is used in outer space.

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