JP2022029152A - Rolling bearing - Google Patents

Abstract

To provide a rolling bearing capable of suppressing the degradation of seal performance.SOLUTION: The rolling bearing includes a seal unit 10A mounted to an end 5a of an outer ring 5 in an axial direction A for sealing a gap between an inner ring 2 and the outer ring 5, the seal unit 10A having a shield member 11 formed of a metallic material, and a contact member 12 mounted to the shield member 11, the shield member 11 including an annular bottom wall part 13, an inside wall part 14 extending from the bottom wall part 13 to the inside in the axial direction A for the contact member 12 to be fixed thereto, and an outside wall part 15 extending from the bottom wall part 13 to the inside in the axial direction A and fixed to the outer ring 5, the contact member 12 including a lip part 18 annularly formed of an elastic material to contact the inner ring 2.SELECTED DRAWING: Figure 3

Description

The present invention relates to rolling bearings.

As rolling bearings, those provided with an inner ring, an outer ring, a plurality of conical rollers, and a seal portion fixed to the outer ring are known (see, for example, Patent Document 1). In the rolling bearing described in Patent Document 1, the seal portion has a core metal fixed to the outer ring and an elastic contact portion integrally formed with the core metal, and the elastic contact portion is an outer peripheral surface of the inner ring. By contacting with, the space between the inner ring and the outer ring is sealed.

Japanese Unexamined Patent Publication No. 2013-29129

Rolling bearings as described above are required to stably secure sealing performance even after handling, for example, during maintenance. Therefore, an object of the present invention is to provide a rolling bearing capable of stably ensuring sealing performance.

The rolling bearing of the present invention is attached to an inner ring, an outer ring, a plurality of rolling elements arranged between the inner ring and the outer ring, and an end portion of the outer ring in the axial direction, and seals between the inner ring and the outer ring. The seal unit comprises a shield member formed of a metal material and a contact member attached to the shield member, wherein the shield member has an annular bottom wall portion and a shaft from the bottom wall portion. Includes and contacts an inner wall that extends inward in the direction and to which the contact member is fixed and an outer wall that extends inward in the axial direction from the bottom wall and is fixed to the outer ring. The member is formed in an annular shape by an elastic material and includes a lip portion in contact with the inner ring.

In this rolling bearing, the seal unit has a shield member formed of a metal material and a contact member attached to the shield member, and the shield member has an annular bottom wall portion and a shaft from the bottom wall portion. It includes an inner side wall portion extending inward in the direction and an outer wall portion extending inward in the axial direction from the bottom wall portion. By forming the shield member in a shape including a substantially U-shaped portion in this way, the rigidity of the shield member can be increased. In addition, since the substantially U-shaped portion is arranged so that the outside in the axial direction is closed, the strength against the external force from the outside (back side) in the axial direction can be increased, and the external force from the outside in the axial direction can be increased. Can be suitably received. As a result, even if an external force acts on the shield member at the time of installation or maintenance of the rolling bearing, for example, the seal unit is unlikely to be damaged. Therefore, according to this rolling bearing, the sealing performance can be stably ensured.

A protrusion protruding in the radial direction may be provided at the tip of the inner side wall portion. In this case, the rigidity of the shield member can be further increased. Further, for example, when a moment load is applied to the shield member, it is possible to prevent the tip portion of the inner side wall portion from expanding or contracting in diameter, and it is possible to improve the moment rigidity of the shield member.

The thickness of the outer side wall portion may be thicker as it approaches the bottom wall portion. In this case, the rigidity of the shield member can be further increased. Further, for example, when a moment load is applied to the shield member, the outer wall portion can suppress the bottom wall portion from bending and deforming inward in the axial direction, further improving the moment rigidity of the shield member. Can be done.

The contact member is formed in an annular shape by a metal material and further includes a core metal fixed to the inner side wall portion, and at least one of the thickness of the bottom wall portion and the thickness of the outer wall portion is thicker than the thickness of the core metal. You may. In this case, the rigidity of the shield member can be effectively increased.

Both the thickness of the bottom wall portion and the thickness of the outer wall portion may be thicker than the thickness of the core metal. In this case, the rigidity of the shield member can be further increased.

The inner side wall portion and the outer wall portion may extend inward in the axial direction from the bottom wall portion. In this case, the rigidity of the shield member can be further increased. Further, the space defined by the bottom wall portion, the inner side wall portion and the outer wall portion can be used as a grease pool.

The thickness of the outer side wall portion may become thinner toward the inside in the axial direction. In this case, the space defined by the bottom wall portion, the inner side wall portion, and the outer wall portion can be widened.

The core metal may be fitted to the inner side wall portion so as to be located on the outer side in the radial direction with respect to the inner side wall portion. In this case, the contact member can be firmly attached to the shield member. In addition, the contact member can be easily attached to the shield member.

The core metal may be fitted to the inner side wall portion so as to be located inside the inner side wall portion in the radial direction. In this case, the contact member can be easily removed from the shield member.

The inner side wall portion is provided with a protrusion so as to project to one side in the radial direction, and the core metal is fitted to the inner side wall portion so as to be located on one side in the radial direction with respect to the inner side wall portion. May be. In this case, the rigidity of the shield member can be further increased.

The shield member may not protrude from the end faces of the inner ring and the outer ring in the axial direction in the axial direction. In this case, it is difficult for an external force to act on the shield member.

The outer side wall portion may be directly fixed to the outer ring. In this case, the number of parts can be reduced as compared with the case where the shield member is fixed to the outer ring via another member, for example.

The contact member may be detachable from the shield member by moving along the axial direction. In this case, the contact member can be easily removed from the shield member.

The plurality of rolling elements may be conical rollers. In this case, the rolling bearing tends to be large in the axial direction. When the rolling bearing becomes large in the axial direction, the handleability deteriorates, and an external force is likely to act on the shield member at the time of installation or maintenance of the rolling bearing. In this respect, according to this rolling bearing, since the rigidity of the shield member is increased, the sealing performance can be stably ensured even in such a configuration.

The plurality of rolling elements may be arranged in a plurality of rows. In this case, the rolling bearing tends to be large in the axial direction. When the rolling bearing becomes large in the axial direction, the handleability deteriorates, and an external force is likely to act on the shield member at the time of installation or maintenance of the rolling bearing. In this respect, according to this rolling bearing, since the rigidity of the shield member is increased, the sealing performance can be stably ensured even in such a configuration.

The seal unit for rolling bearings of the present invention is a sealing unit used for sealing between an inner ring and an outer ring in a rolling bearing, and includes a shield member formed of a metal material, a contact member attached to the shield member, and the like. The shield member comprises an annular bottom wall portion, an inner side wall portion extending from the bottom wall portion in a direction perpendicular to the bottom wall portion, and a shield member along a direction perpendicular to the bottom wall portion to the bottom wall portion. It has an outer wall portion that extends and is fixed to the outer ring, and the contact member is formed in an annular shape by a metal material and is formed in an annular shape by a core metal fixed to an inner side wall portion and an elastic material. With a lip portion in contact with, at least one of the thickness of the bottom wall portion and the thickness of the outer wall portion is thicker than the thickness of the core metal. According to this seal unit, the seal performance can be stably ensured for the above-mentioned reason.

According to the present invention, it is possible to provide a rolling bearing capable of suppressing deterioration of sealing performance.

It is sectional drawing of the peripheral part of the rolling bearing which concerns on embodiment. It is sectional drawing of the rolling bearing. It is sectional drawing of a part of a rolling bearing. It is sectional drawing of the 1st seal unit. It is a figure which shows the state which the rolling bearing of the comparative example is arranged in the axle box. It is a figure which shows the state which the rolling bearing of the comparative example is suspended by the suspension jig. (A) is a cross-sectional view showing a state in which the rolling bearing of the comparative example is normally suspended, and (b) is a cross-sectional view showing a state in which the rolling bearing of the comparative example is not normally suspended. be. (A) and (b) are sectional views showing how the rolling bearing of the comparative example is hit by a metal rod. It is sectional drawing of the 1st seal unit which concerns on a modification.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. In the following description, the same reference numerals will be used for the same or equivalent elements, and duplicate description will be omitted.
[Composition of rolling bearing]

The rolling bearing 1 shown in FIG. 1 is configured as a roll neck bearing that supports the roll neck portion N of the steel rolling mill. The rolling bearing 1 is a multi-row conical roller bearing and can receive both a radial load and an axial load. The rolling bearing 1 is arranged in the axle box (chock) C.

In the rolling bearing 1, as will be described later, the space between the inner ring and the outer ring is sealed by a seal unit, and the space between the inner ring and the outer ring is sealed. This makes it possible to prevent the grease sealed in the space between the inner ring and the outer ring from leaking to the outside of the rolling bearing 1. Further, it is possible to prevent the rolling water (cooling water) sprayed on the roll of the steel rolling mill and the oxide scale (iron oxide powder) peeled off from the steel pieces from entering the inside of the rolling bearing 1. Therefore, according to the rolling bearing 1, it is possible to reduce the frequency of replenishing grease, improve maintainability, and suppress premature damage to the bearing due to the ingress of rolling water and oxide scale.

As shown in FIGS. 1 and 2, the rolling bearing 1 includes a first inner ring 2, a second inner ring 3, a first outer ring 4, a second outer ring 5, a third outer ring 6, and a plurality of rolling elements. 7, a plurality of cages 8, a first seal unit 10A, and a second seal unit 10B are provided.

The first inner ring 2 is arranged on the first side (one side) S1 in the axial direction A with respect to the second inner ring 3. In other words, the second inner ring 3 is arranged on the second side (the other side) S2 in the axial direction A with respect to the first inner ring 2. The second side S2 in the axial direction A is opposite to the first side S1 in the axial direction A. The first inner ring 2 is in contact with the second inner ring 3.

As shown in FIG. 2, the first inner ring 2 has a raceway surface 21, an inner surface 22, and an end surface 23. The end face 23 is the end face of the first side S1 in the axial direction A. The second inner ring 3 has a raceway surface 31, an inner surface 32, and an end surface 33. The end face 33 is the end face of the second side S2 in the axial direction A. The inner surface 22 and the inner surface 32 are fitted with the roll neck portion N. A cylindrical intermediate seal 91 is arranged at the boundary between the inner surface 22 and the inner surface 32, and the intermediate seal 91 seals between the inner surface 22 and the inner surface 32. Grooves 22a and 32a are formed on the inner surfaces 22 and 32, respectively, and the intermediate seal 91 is arranged in the grooves 22a and 32a.

The second outer ring 5 is arranged on the first side S1 in the axial direction A with respect to the first outer ring 4. The third outer ring 6 is arranged on the second side S2 in the axial direction A with respect to the first outer ring 4. That is, the second outer ring 5 and the third outer ring 6 are arranged so as to sandwich the first outer ring 4 in the axial direction A. The first outer ring 4 faces the portion of the second side S2 in the first inner ring 2 and the portion of the first side S1 in the second inner ring 3 in the radial direction R. The second outer ring 5 faces the portion of the first inner ring 2 on the first side S1 in the radial direction R. The third outer ring 6 faces the portion of the second inner ring 3 on the second side S2 in the radial direction R.

The first outer ring 4 has a raceway surface 41 and an outer surface 42. The second outer ring 5 has a raceway surface 51, an outer surface 52, and an end surface 53. The end face 53 is the end face of the first side S1 in the axial direction A. The third outer ring 6 has a raceway surface 61, an outer surface 62, and an end surface 63. The end face 63 is the end face of the second side S2 in the axial direction A. The outer surface 42, the outer surface 52, and the outer surface 62 are fitted to the inner surface Ca (FIG. 1) of the axle box C. A cylindrical spacer 92 is interposed between the first outer ring 4 and the second outer ring 5, and a cylindrical spacer 93 is interposed between the first outer ring 4 and the third outer ring. .. Grooves 52a and 62a are formed on the outer surface 52 and the outer surface 62, respectively, and an annular O-ring 94 is arranged on each of the grooves 52a and 62a. An O-ring 94 seals between the outer surfaces 42, 52, 62 and the inner surface Ca of the axle box C.

The plurality of rolling elements 7 include a plurality of first rolling elements 7a, a plurality of second rolling elements 7b, a plurality of third rolling elements 7c, and a plurality of fourth rolling elements 7d. The first rolling element 7a is arranged between the raceway surface 21 of the first inner ring 2 and the raceway surface 51 of the second outer ring 5. The second rolling element 7b is arranged between the raceway surface 21 of the first inner ring 2 and the raceway surface 41 of the first outer ring 4. The third rolling element 7c is arranged between the raceway surface 31 of the second inner ring 3 and the raceway surface 41 of the first outer ring 4. The fourth rolling element 7d is arranged between the raceway surface 31 of the second inner ring 3 and the raceway surface 61 of the third outer ring 6. In this way, the plurality of rolling elements 7 are arranged in a plurality of rows (4 rows in this example).

Each rolling element 7 is a conical roller. The first rolling element 7a and the third rolling element 7c are arranged so that the top surface faces the first side S1 in the axial direction A, and the second rolling element 7b and the fourth rolling element 7d have the top surface as the axis. It is arranged so as to face the second side S2 in the direction A. Each of the plurality of first rolling elements 7a, the plurality of second rolling elements 7b, the plurality of third rolling elements 7c, and the plurality of fourth rolling elements 7d can rotate at regular intervals between the orbital planes. , Held by the cage 8.

The first seal unit 10A is attached to the end portion 5a of the second outer ring 5 in the axial direction A, and seals between the first inner ring 2 and the second outer ring 5. The second seal unit 10B is attached to the end portion 6a of the third outer ring 6 in the axial direction A, and seals between the second inner ring 3 and the third outer ring 6.
[Seal unit configuration]

The configuration of the first seal unit 10A will be further described. The rolling bearing 1 is configured to be plane-symmetrical with respect to a surface (a boundary surface between the first inner ring 2 and the second inner ring 3) that passes through the center of the rolling bearing 1 in the axial direction A and is perpendicular to the axial direction A. Therefore, the description of the configuration of the second seal unit 10B will be omitted.

As shown in FIGS. 3 and 4, the first seal unit 10A has a shield member 11 and a contact member 12 attached to the shield member 11. The shield member 11 is formed in an annular shape from a metal material such as steel. The shield member 11 has a bottom wall portion 13, an inner side wall portion 14, and an outer wall portion 15. Each of the bottom wall portion 13, the inner side wall portion 14, and the outer wall portion 15 is formed in an annular shape. The shield member 11 has a U-shape (C-shape) in which the opening faces the inside (bearing center side) in the axial direction A in the cross section along the axial direction A.

The bottom wall portion 13 is formed in the shape of an annular flat plate and extends along a plane parallel to the radial direction R (perpendicular to the axial direction A). The inner side wall portion 14 extends from the bottom wall portion 13 along the axial direction A (along the direction perpendicular to the bottom wall portion 13). More specifically, the inner side wall portion 14 extends inward in the axial direction A from the inner edge of the bottom wall portion 13 in the radial direction R. The inner side wall portion 14 extends parallel to the axial direction A. The inner side wall portion 14 extends over the entire circumference and is formed in a cylindrical shape having a center line parallel to the axial direction A. A protrusion 16 is provided on the inner edge (tip of the inner side wall portion 14) of the inner side wall portion 14 in the axial direction A so as to project inward in the radial direction R. The protrusion 16 extends over the entire circumference and is formed in an annular shape.

The outer side wall portion 15 extends from the bottom wall portion 13 along the axial direction A. More specifically, the outer wall portion 15 extends inward in the axial direction A from the outer edge of the bottom wall portion 13 in the radial direction R. The outer side wall portion 15 extends over the entire circumference and is formed in a cylindrical shape having the same center line as the inner side wall portion 14. The thickness of the outer side wall portion 15 becomes thinner toward the inside in the axial direction A. The inner surface 15a of the outer wall portion 15 in the radial direction R is inclined with respect to the axial direction A so as to be toward the inside in the axial direction A and toward the outside in the radial direction R. The outer surface 15b of the outer wall portion 15 in the radial direction R is a cylindrical surface having a center line parallel to the axial direction A. In other words, the thickness of the outer wall portion 15 becomes thicker as it approaches the bottom wall portion 13. The inner surface 15a is inclined with respect to the axial direction A so as to approach the bottom wall portion 13 toward the inside in the radial direction R.

The shield member 11 is fixed to the end portion 5a of the second outer ring 5 by fitting the outer wall portion 15 with the inner surface 54 of the second outer ring 5. The inner surface 54 is formed on the first side S1 in the axial direction A with respect to the raceway surface 51, and is connected to the end surface 53. The inner surface 54 is an inner peripheral surface of the end portion 5a (cylindrical portion) of the second outer ring 5, and is a cylindrical surface having the same center line as the outer wall portion 15. The shield member 11 is directly fixed to the second outer ring 5. That is, no other member such as a seal holder is interposed between the shield member 11 and the second outer ring 5. Further, in a state where the shield member 11 is fixed to the second outer ring 5, the tip surface 15c (FIG. 4) of the outer wall portion 15 is formed between the raceway surface 51 and the inner surface 54 in the second outer ring 5. It is in contact with the step surface 55 (step portion) (FIG. 3). The tip surface 15c and the stepped surface 55 are annular flat surfaces. When the shield member 11 is fixed to the second outer ring 5, the shield member 11 can be easily positioned by bringing the tip surface 15c into contact with the stepped surface 55.

In the state where the shield member 11 is fixed to the second outer ring 5, the shield member 11 does not protrude from the end surface 23 of the first inner ring 2 and the end surface 53 of the second outer ring 5 in the axial direction A. That is, the entire shield member 11 is located inside the end surface 23 and the end surface 53 in the axial direction A. As shown in FIG. 2, the shield member 11 of the second seal unit 10B is fixed to the end portion 6a of the third outer ring 6 by fitting the outer wall portion 15 with the inner surface 64 of the third outer ring 6. Has been done. The inner surface 64 is formed on the second side S2 in the axial direction A with respect to the raceway surface 61.

The contact member 12 has a core metal 17 and a lip portion 18 integrally formed with the core metal 17. Each of the core metal 17 and the lip portion 18 is formed in an annular shape. The core metal 17 is formed of a metal material such as steel in a cylindrical shape having the same center line as the inner side wall portion 14.

The lip portion 18 has a first portion 18a, a second portion 18b, and a third portion 18c. Each of the first portion 18a, the second portion 18b and the third portion 18c is formed in an annular shape. The first portion 18a is formed in a substantially cylindrical shape integrally with the core metal 17. The second portion 18b extends inward in the radial direction R from the inner edge of the first portion 18a in the axial direction A, and is formed in an annular shape. The third portion 18c extends from the inner edge of the second portion 18b in the radial direction R. The third portion 18c is inclined and extends toward the inside in the radial direction R toward the outside in the axial direction A.

The lip portion 18 is formed of an elastic material such as rubber. Examples of the elastic material constituting the lip portion 18 include nitrile rubber, hydrogenated nitrile rubber, fluororubber, and the like. The material of the lip portion 18 is selected, for example, according to the rotation speed of the roll of the steel rolling mill.

The contact member 12 is fixed to the shield member 11 by fitting the core metal 17 to the inner side wall portion 14 of the shield member 11. In this example, the core metal 17 is fitted to the inner side wall portion 14 so as to be located on the outer side in the radial direction R with respect to the inner side wall portion 14 (on the outer surface 14a side of the inner side wall portion 14). A first portion 18a of the lip portion 18 is interposed between the core metal 17 and the outer surface 14a. The first portion 18a is in contact with the outer surface 14a of the inner side wall portion 14.

In a state where the core metal 17 is fixed to the inner side wall portion 14, the tip end portion of the third portion 18c of the lip portion 18 comes into contact with the outer surface 24 of the first inner ring 2. The outer surface 24 is formed on the first side S1 in the axial direction A with respect to the raceway surface 21, and is connected to the end surface 23. The outer surface 24 is a cylindrical surface having the same center line as the inner side wall portion 14. As shown in FIG. 2, in the second seal unit 10B, the lip portion 18 of the contact member 12 comes into contact with the outer surface 34 of the second inner ring 3. The outer surface 34 is formed on the second side S2 in the axial direction A with respect to the raceway surface 31.

With reference to FIG. 4, the relationship between the thicknesses of the shield member 11 and the contact member 12 will be described. Both the thickness T13 of the bottom wall portion 13 and the thickness T15 of the outer wall portion 15 are thicker than the thickness T17 of the core metal 17. The thickness T15 is thicker than the thickness T13. The thickness T14 of the inner side wall portion 14 is the same as the thickness T17 of the core metal 17, but may be thinner than the thickness T17 or may be thicker than the thickness T17. The thickness T13 of the bottom wall portion 13 is the thickness in the axial direction A, which is the maximum thickness. In this example, the total thickness of the bottom wall portion 13 is thicker than the thickness T17 of the core metal 17. The thickness T14 of the inner side wall portion 14 is the thickness in the radial direction R, and is the maximum thickness in the portion excluding the protrusion 16. The thickness T15 of the outer side wall portion 15 is the thickness in the radial direction R, and is the maximum thickness. In this example, the thickness T15 is maximum at the end of the first side S1 in the axial direction A. In this example, the thickness (minimum thickness) of the outer wall portion 15 at the end portion of the second side S2 is also thicker than the thickness T17 of the core metal 17. That is, the total thickness of the outer wall portion 15 is thicker than the thickness T17 of the core metal 17. The thickness T17 of the core metal 17 is the thickness in the radial direction R (the direction perpendicular to the extending direction of the core metal 17), and is the maximum thickness.
[Action and effect]

The rolling bearing 101 of the comparative example will be described with reference to FIGS. 5 to 8. In the rolling bearing 101 of the comparative example, the first seal unit 110A is provided in place of the first seal unit 10A. As shown in FIG. 7, the first seal unit 110A has a seal holder 111 fixed to the second outer ring 5 and a seal portion 112. The seal portion 112 has a core metal 113 fixed to the seal holder 111 and a contact portion 114 integrally formed with the core metal 113, and the contact portion 114 comes into contact with the first inner ring 2. , The space between the first inner ring 2 and the second outer ring 5 is sealed.

Further, in the rolling bearing 101 of the comparative example, the second seal unit 110B is provided in place of the second seal unit 10B. As shown in FIG. 8, the second seal unit 110B has a metal seal holder 111 fixed to the second outer ring 5 and a seal portion 112. The seal portion 112 has a core metal 113 fixed to the seal holder 111 and a contact portion 114 integrally formed with the core metal 113, and the contact portion 114 comes into contact with the second inner ring 3. , The space between the second inner ring 3 and the third outer ring 6 is sealed.

When installing the rolling bearing 101, the rolling bearing 101 is arranged in the axle box C as shown in FIG. At this time, the rolling bearing 101 is suspended by the suspension jig 120 shown in FIG. 6, and the rolling bearing 101 is inserted into the axle box C in the suspended state. The hanging jig 120 has a claw portion 121 that can be moved along the radial direction R. As shown in FIG. 7A, it is preferable that the claw portion 121 supports the seal holder 111 when the suspension is suspended by the suspension jig 120. However, as shown in FIG. 7B, the claw portion 121 may not be properly arranged, and the seal portion 112 may receive a load from the claw portion 121. In this case, the seal portion 112 may be damaged. Damage to the sealing portion 112 can cause an early deterioration in sealing performance or a sudden failure. In the case of FIG. 7B, the claw portion 121 comes into contact with the seal holder 111 when the rolling bearing 101 is suspended while the claw portion 121 is in contact with the first inner ring 2. This is because the rolling element 7 and the cage 8 move along the axial direction A with respect to the second outer ring 5. The reason why the first inner ring 2, the rolling element 7 and the cage 8 move in the axial direction A is that there is a gap between the rolling element 7 and the raceway surface in order to prevent the influence of heat generation due to rotation. Is.

In addition, the seal portion 112 may be damaged due to the following reasons. The outer surface of the rolling bearing 101 (the outer surface of the first outer ring 4, the second outer ring 5 and the third outer ring 6) is fitted to the inner surface Ca of the axle box C by loose fitting (gap fitting). If the rolling bearing 101 is inserted into the axle box C in a tilted state, the rolling bearing 101 is caught by the axle box C and cannot be inserted. In that case, as shown in FIG. 8A, the inclination of the rolling bearing 101 is corrected by hitting the seal holder 111 with the metal rod 130 made of brass or the like. However, as shown in FIG. 8B, the seal portion 112 may be accidentally hit. In this case, the seal portion 112 may be damaged. Improper placement of the claw portion 121 and improper work by the metal rod 130 as described above are likely to occur due to an increase in maintenance frequency due to an increase in production volume, a decrease in skilled workers, and the like.

On the other hand, in the rolling bearing 1 of the embodiment, the first seal unit 10A has a shield member 11 formed of a metal material and a contact member 12 attached to the shield member 11, and the shield member 11 has a shield member 11. , An annular bottom wall portion 13, an inner side wall portion 14 extending inward in the axial direction A from the bottom wall portion 13, and an outer wall portion extending inward in the axial direction A from the bottom wall portion 13. 15 and. By forming the shield member 11 in a shape including a substantially U-shaped portion in this way, the rigidity of the shield member 11 can be increased. Further, since the substantially U-shaped portion is arranged so that the outer side in the axial direction A is closed, the strength against the external force from the outer side (rear surface side) in the axial direction A can be increased, and the outer side in the axial direction A can be increased. Can suitably receive external force from. As a result, even if an external force acts on the shield member 11 at the time of installation or maintenance of the rolling bearing 1 as described above, the first seal unit 10A is unlikely to be damaged. Therefore, according to the rolling bearing 1, the sealing performance can be stably ensured.

A protrusion 16 projecting in the radial direction R is provided at the tip of the inner side wall portion 14. As a result, the rigidity of the shield member 11 can be further increased. Further, for example, when a moment load is applied to the shield member 11, it is possible to prevent the tip portion of the inner side wall portion 14 from expanding or contracting in diameter, and it is possible to improve the moment rigidity of the shield member 11.

The thickness of the outer side wall portion 15 becomes thicker as it approaches the bottom wall portion 13. As a result, the rigidity of the shield member 11 can be further increased. Further, for example, when a moment load is applied to the shield member 11, the outer wall portion 15 can suppress the bottom wall portion 13 from bending and deforming inward in the axial direction A, and the moment rigidity of the shield member 11 can be suppressed. Can be further improved.

The contact member 12 is formed in an annular shape by a metal material and includes a core metal 17 fixed to the inner side wall portion 14, both of which have a thickness T13 of the bottom wall portion 13 and a thickness T15 of the outer wall portion 15. The thickness of the core metal 17 is thicker than that of T17. As a result, the rigidity of the shield member 11 can be effectively increased.

The inner side wall portion 14 and the outer wall portion 15 extend inward in the axial direction A from the bottom wall portion 13. As a result, the rigidity of the shield member 11 can be further increased. Further, the space S (FIG. 4) defined by the bottom wall portion 13, the inner side wall portion 14, and the outer wall portion 15 can be used as a grease pool.

The thickness T15 of the outer side wall portion 15 becomes thinner toward the inside in the axial direction A. Thereby, the space S defined by the bottom wall portion 13, the inner side wall portion 14, and the outer wall portion 15 can be widened.

The core metal 17 is fitted to the inner side wall portion 14 so as to be located on the outer side in the radial direction R with respect to the inner side wall portion 14. As a result, the contact member 12 can be firmly attached to the shield member 11. Further, the contact member 12 can be easily attached to the shield member 11.

The shield member 11 does not protrude from the end surface 23 of the first inner ring 2 and the end surface 53 of the second outer ring 5 in the axial direction A in the axial direction A. As a result, it is difficult for an external force to act on the shield member 11.

The outer side wall portion 15 is directly fixed to the second outer ring 5. As a result, the number of parts can be reduced as compared with the case where the shield member 11 is fixed to the second outer ring 5 via another member (for example, the seal holder 111).

A plurality of rolling elements 7 are conical rollers arranged in a plurality of rows. In this case, the rolling bearing 1 tends to increase in size in the axial direction A. When the rolling bearing 1 is enlarged in the axial direction A, the handleability is deteriorated, and an external force is likely to act on the shield member 11 at the time of installation or maintenance of the rolling bearing 1. In this respect, according to the rolling bearing 1, since the rigidity of the shield member 11 is increased, the sealing performance can be stably ensured even in such a configuration.
[Modification example]

In the first seal unit 10C of the modified example shown in FIG. 9, the core metal 17 is located inside the inner side wall portion 14 in the radial direction R (on the inner surface 14b side of the inner side wall portion 14). It is fitted to the wall portion 14. More specifically, the core metal 17 is fitted to the inner surface 14b. The core metal 17 is in contact with the protrusion 16. The shield member 11 and the contact member 12 do not project from the end surface 23 of the first inner ring 2 and the end surface 53 of the second outer ring 5 in the axial direction A.

In the first seal unit 10C, the contact member 12 can be attached to and detached from the shield member 11 by moving along the axial direction A. That is, by moving the contact member 12 along the axial direction A, the contact member 12 can be attached to the shield member 11 and the contact member 12 can be removed from the shield member 11. This is because, in a state where the shield member 11 is fixed to the second outer ring 5 and the contact member 12 is fixed to the shield member 11, no other member is arranged outside the shield member 11 in the axial direction A. be. That is, in this state, the entire shield member 11 is exposed when viewed from the outside (first side S1) in the axial direction A (the shield member 11 does not overlap with other members).

Even with such a modification, the rigidity of the shield member 11 can be increased and the sealing performance can be stably ensured as in the above embodiment. Further, since the core metal 17 is fitted to the inner side wall portion 14 so as to be located inside the inner side wall portion 14 in the radial direction R, the contact member 12 can be easily removed from the shield member 11. Further, the contact member 12 can be attached to and detached from the shield member 11 by moving along the axial direction A. This also makes it easier to remove the contact member 12 from the shield member 11. Further, the inner side wall portion 14 is provided with a protrusion 16 so as to project inward (one side) in the radial direction R, and the core metal 17 is located inside the inner side wall portion 14 in the radial direction R. It is fitted to the inner side wall portion 14 so as to do so. As a result, the rigidity of the shield member 11 can be further increased.

The present invention is not limited to the above embodiments and modifications. As the material and shape of each configuration, not only the above-mentioned material and shape but also various materials and shapes can be adopted. For example, the metal material constituting the shield member 11 and the core metal 17, and the elastic material constituting the lip portion 18 may be any material. The inner side wall portion 14 does not necessarily have to be formed in an annular shape (cylindrical shape), may be formed intermittently along the circumferential direction, or has a notch in a part in the circumferential direction. May be good. This point is the same for the outer wall portion 15.

In the above embodiment, both the thickness T13 of the bottom wall portion 13 and the thickness T15 of the outer wall portion 15 are thicker than the thickness T17 of the core metal 17, but at least one of the thickness T13 and the thickness T15 is thicker. It suffices to be thicker than the thickness T17, and either one of the thickness T13 and the thickness T15 may be thicker than the thickness T17. Even in this case, the rigidity of the shield member 11 can be increased and the sealing performance can be stably ensured as in the above embodiment. At least one of the thickness T13 and the thickness T15 may be thinner than the thickness T17. The contact member 12 does not have to include the core metal 17. The protrusion 16 may protrude outward in the radial direction from the tip of the inner side wall portion 14.

The inner side wall portion 14 and the outer wall portion 15 may extend from the bottom wall portion 13 toward both the inside and the outside in the axial direction A. For example, the shield member 11 may have an I-shape in a cross section parallel to the axial direction A.

In the above embodiment, the rolling element 7 is a conical roller, but the rolling element 7 may be a cylindrical roller. The rolling elements 7 may not be arranged in a plurality of rows, but may be arranged in a single row. The protrusion 16 may not be provided. The thickness T15 of the outer side wall portion 15 may be uniform with respect to the axial direction A. The outer side wall portion 15 may be fixed to the second outer ring 5 via a seal holder.

1 ... rolling bearing, 2 ... first inner ring, 5 ... second outer ring, 5a ... end, 7 ... rolling element, 10A ... first seal unit (rolling bearing seal unit), 11 ... shield member, 12 ... contact member , 13 ... bottom wall portion, 14 ... inner side wall portion, 15 ... outer wall portion, 16 ... protrusion, 18 ... lip portion, A ... axial direction, R ... radial direction.

Claims (3)

Inner ring and
With the outer ring
A plurality of rolling elements arranged between the inner ring and the outer ring, and
A seal unit, which is attached to the end of the outer ring in the axial direction and seals between the inner ring and the outer ring, is provided.
The seal unit has a shield member formed of a metal material and a contact member attached to the shield member.
The shield member is
The annular bottom wall and
An inner side wall portion extending inward in the axial direction from the bottom wall portion and to which the contact member is fixed, and an inner side wall portion.
Including an outer wall portion extending inward in the axial direction from the bottom wall portion and fixed to the outer ring.
The contact member is a rolling bearing formed of an elastic material in an annular shape and including a lip portion in contact with the inner ring. The rolling bearing according to claim 1, wherein a protrusion protruding in the radial direction is provided at the tip of the inner side wall portion. The rolling bearing according to claim 1 or 2, wherein the thickness of the outer wall portion becomes thicker as it approaches the bottom wall portion.

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