JP2003278772A - Ball bearing - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a ball bearing whose life is increased by enhancing the flowability of grease so that a large amount of the grease contributes to lubrication. <P>SOLUTION: The grease-lubricated ball bearing 10 comprises an inner ring 12, an outer ring 11, a crown type cage 15, a plurality of balls 13 retained by the cage 15, and annular sealing members 16 provided on both axial sides of the balls 13. A protruding part 17 is provided for reducing a space volume surrounded by the sealing member 16 on the pocket opening side of the cage 15 as well as by the inner and outer rings and the balls 13. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a grease-lubricated rolling bearing, and more particularly, to a ball bearing used in a rotary motion part of an automobile or various power plants.

[0002]

2. Description of the Related Art A ball bearing having a seal and used for grease lubrication is widely used to form various rotary support members, as disclosed in Japanese Patent Application Laid-Open No. 2004-242242. With respect to such a ball bearing having a seal and used for grease lubrication, as a technique for improving lubricity and extending the life, for example, as disclosed in Patent Document 2, Patent Document 3 and Patent Document 4 below, Techniques for improving the shape of the cage to improve the grease fluidity are known. As shown in FIG. 14, a conventional ball bearing 80 has an outer ring 83 having an outer ring raceway 84 on an inner peripheral surface, an inner ring 81 having an inner ring raceway 82 on an outer peripheral surface, and a space between the outer ring raceway 84 and the inner ring raceway 82. A plurality of balls 85 rotatably mounted on the inner ring 81 of the outer ring 83 and the inner ring 81.
And a retainer 87 that is arranged between the outer peripheral surface of the retainer 87 and the outer peripheral surface of the retainer 87 and rotatably holds the plurality of balls 85. The ball bearing 80 further includes a pair of annular seal members 86, 86 which are provided on both sides of the ball 85 in the axial direction and partition the bearing internal space from the outside. Grease is filled in the bearing internal space surrounded by the seal members 86, 86. Seal member 86
In general, the base end portion (outer peripheral portion) thereof is mounted and fixed to the outer ring 83. The contact member of the seal member 86 has one or a plurality of lips at its tip (inner peripheral portion), and its tip is located in a seal groove formed at the axial end of the inner ring. , Sliding contact with the seal groove.

In the example shown in FIG. 14, the crown type cage 87 shown in FIG. 15 is used. As shown in FIG. 15, the crown-shaped cage 87 has a plurality of pockets 88 for holding balls at equal intervals in the circumferential direction. Pocket 88
The crown-shaped cage 87 is open at one axial side (upper side in the figure). The crown type cage 87 is superior to the corrugated type press cage in terms of self-lubricating property, low friction characteristic, light weight, low noise, etc., and thus is preferably used in a high speed environment.

[0004]

[Patent Document 1] Japanese Unexamined Patent Publication No. 2002-130305 (pages 1-4, FIG. 1)

[Patent Document 2] Japanese Patent Application Laid-Open No. 11-182554 (second
(Page, Fig. 1)

[Patent Document 3] Japanese Utility Model Laid-Open No. 5-73318 (No. 5-7)
Page, Fig. 1-6)

[Patent Document 4] Japanese Patent Laid-Open No. 2000-145787 (Page 2-3, FIG. 1-5)

[0005]

SUMMARY OF THE INVENTION The above-mentioned sealing member 8
When 6 is used in combination with the crown type cage 87, the grease existing between the cage pocket opening side and the inner surface of the seal member 86 facing the cage pocket (area S shown in FIG. 14) remains and hardly flows. It was previously feared that it might not have contributed to lubrication. Therefore, in order to confirm that, the seal member 86 is made of transparent acrylic, and the grease mixed with the dye is applied to the seal member 86.
The inner ring 81 was rotated and the behavior of the grease was observed visually or with a high-speed video camera or the like. As a result, while the grease existing between the cage end surface on the side opposite to the pocket opening side and the seal member inner surface facing it actively flows and contributes to lubrication, the cage end surface on the pocket opening side and it It was found that the grease existing in the space S between the facing inner surface of the seal member 86 hardly flowed and remained.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a ball bearing which can improve the fluidity of grease and contribute a large amount of grease to lubrication, and can improve the life. To do.

[0007]

The object of the present invention is achieved by the following constitution. (1) Inner ring, outer ring, crown type cage arranged between the inner and outer rings, a plurality of balls held by the crown type cage, and annular seals provided on both sides of the ball in the axial direction. In a ball bearing having a member and lubricated with grease, a protrusion for reducing the space volume surrounded by the sealing member on the pocket opening side of the crown type retainer, the inner and outer rings and the ball is provided. Ball bearings that are characterized by (2) The ball bearing according to (1), wherein the protrusion is provided on the inner surface of the seal member on the pocket opening side of the crown type cage. (3) The ball bearing according to (2), wherein the protrusion is provided in a band shape along the circumferential direction of the seal member. (4) The ball bearing according to (2), wherein a plurality of the protrusions are provided at intervals in the circumferential direction of the seal member. (5) The ball bearing according to any one of (2) to (4), wherein the protrusion is integrally formed with the seal member. (6) The ball bearing according to (5), wherein the seal member has a core material, and the protrusion is integrally formed with the core material.

(7) The ball bearing according to (1), wherein the protruding portion is formed of rubber. (8) The seal member includes the core member and a rubber member having a lip portion and a seal fixing portion and attached to the core member, and the protrusion is integrally formed with the rubber member. The ball bearing according to 1) or 7). (9) The ball bearing according to (7) or (8), wherein the protrusion has a triangular prism shape and a plurality of protrusions are provided at intervals in the circumferential direction. (10) In the above (7) or (8), the protrusion has a substantially quadrangular truncated pyramid shape having an arc-shaped portion concentric with the ball at the tip, and is provided at intervals in the circumferential direction. Ball bearing described. (11) The above-mentioned (7) or (8), wherein the projecting portion is in the shape of a quadrangular pyramid and is provided in plural at intervals in the circumferential direction.
Ball bearing described in. (12) Inner ring, outer ring, crown type cage arranged between the inner and outer rings, a plurality of balls held by the crown type cage, and annular seals provided on both sides of the ball in the axial direction. In a ball bearing having a member and lubricated with grease, the axial distance between the seal member on the pocket opening side of the crown type retainer and the ball is determined by the axial distance between the seal member on the counter pocket opening side and the ball. A ball bearing characterized by being narrower than the directional spacing.

According to the ball bearing having the above structure, the space volume surrounded by the sealing member, the inner and outer rings, and the ball facing the pocket opening side of the crown type retainer is reduced by the protrusion, thereby reducing the volume. The fluidity of the grease existing in the open space can be improved to contribute to lubrication. If the protrusion is provided on the inner surface of the seal member facing the pocket opening side of the crown type cage, the fluidity of the grease existing in the space of which the volume is reduced by the protrusion of the seal member is improved to contribute to lubrication. Can be made. It is also possible to use the conventional ones as the inner ring, the outer ring and the balls. If the seal member is fixed to the outer ring, especially when the outer ring rotates, the protrusion moves relative to the ball together with the outer ring to positively bring the grease into contact with the ball. The protrusion is
If the rubber is molded using rubber as the material, the rubber can be molded comparatively easily even if it has a complicated shape, so that the protrusion can be manufactured without increasing the number of steps.

If the seal member is composed of a core member and a rubber member having a lip portion and a seal fixing portion and attached to the core member, and the protruding portion is integrally molded with the rubber member, the seal member is manufactured. In doing so, since the protruding portion is made at the same time as the rubber member having the lip portion and the seal fixing portion, the productivity can be improved. As the shape of the protruding portion, a plurality of triangular prisms are provided at intervals in the circumferential direction, or a plurality of pyramidal pyramid shapes having an arc-shaped portion concentric with the ball at the tip end are formed at intervals in the circumferential direction. If they are provided, or if they are provided in the shape of a quadrangular pyramid and spaced in the circumferential direction, the fluidity of the grease existing in the space whose volume is reduced by the protrusions of those shapes can be improved and contribute to lubrication. Can
it can. The space volume on the pocket opening side can also be reduced by making the axial distance between the seal member on the pocket opening side of the crown type cage and the ball smaller than the axial distance between the seal member on the counter pocket opening side and the ball. You can In this case, the fluidity of the grease can be improved without providing the protrusion.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 shows a ball bearing 10 according to the first embodiment of the present invention. The ball bearing 10 includes an outer ring 11, an inner ring 12, a plurality of balls 13 arranged between the outer ring 11 and the inner ring 12, and a crown type cage 15 provided with pockets for holding the balls 13 at equal intervals in the circumferential direction. Is equipped with.

Annular seal members 16 and 16 are provided on both sides of the ball 13 in the axial direction. Sealing member 16
Is a rubber member (elastic body) 16a.
It is covered with. The seal member 16 is attached to the outer ring 11 after the balls 13 are mounted between the inner and outer rings. The seal member 16 is a contact type in which the base end portion is mounted and fixed to the outer ring 11 and the tip end portion is in sliding contact with the inner ring 12. For example, a rubber member 16a may be attached to a core metal 16b manufactured by pressing a steel plate such as JIS SPCC.
May be adhered or fixed by baking. Grease is filled in the bearing internal space that is partitioned from the outside by the seal member 16, and the grease allows the space between the ball 13 and the outer ring raceway 11a of the outer ring and the inner ring raceway 12a of the inner ring, or between the ball 13 and the crown-shaped holding. The space between the container 15 and the container is lubricated.

A seal member (a seal member on the left side in the figure) 1 arranged to face the pocket opening side of the crown type cage 15
A projecting portion 17 is provided on the inner surface of 6. Protrusion 1
7 is formed in a strip shape having a rectangular cross section and continuously extending along the circumferential direction of the seal member 16, and projects toward the ball 13 in parallel to the axial direction. The protrusion 17 has a function of reducing the space volume of the region S shown in FIG. 1 surrounded by the seal member 16, the inner and outer races 11 and 12, and the balls 13.
The protruding portion 17 is arranged in a region S surrounded by the seal member 16, the inner and outer rings 11, 12 and the ball 13.

As shown in FIG. 2A, the protrusion 17 is
It is formed in an annular shape in a plan view. In this embodiment, as shown in FIG. 2B, which is a side view, the protrusion 17 formed separately from the cored bar 16b is attached to the cored bar 16b by adhesion, caulking, welding, or the like.

The ball bearing 10 of the first embodiment can be used for both inner ring rotation and outer ring rotation. In the case of outer ring rotation, the seal member 16 rotates together with the outer ring 11,
The protrusion 17 not only reduces the space in which the grease stays, but also agitates the grease as the seal member 16 rotates to promote the flow. In the case of the inner ring rotation, since the outer ring 11 does not rotate, the grease agitating action by the protrusions 17 cannot be expected so much, but the protrusions 17 formed in a rectangular shape in a sectional view and continuously extending in the circumferential direction can reduce the area S. The space volume can be significantly reduced, and grease can be prevented from staying.

FIG. 3 shows a ball bearing 2 according to a second embodiment of the present invention.
Indicates 0. In the embodiments described below, members having the same configurations and functions as those already described are given the same reference numerals in the drawings to simplify or omit the description. The ball bearing 20 of the second embodiment is circumferentially arranged on the inner surface of a seal member (the left seal member in the figure) 16 which is arranged facing the pocket opening side of the crown type cage 15 and fixedly mounted to the outer ring 11. A plurality of protrusions 21 are provided at intervals. The projecting portion 21 is arranged in a region S surrounded by the seal member 16, the inner and outer races 11 and 12, and the ball 13, and projects toward the ball 13 in parallel to the axial direction.

As shown in FIG. 4 (a), a plurality (here, 12) of protrusions 21 are provided at equal intervals in the circumferential direction. In this embodiment, FIG. 4B is a side view.
As shown in FIG. 6, a member formed in a corrugated plate annular shape, which is separate from the core metal 16b, is formed by adhesion, caulking, welding, or the like.
It is attached to b. Each protruding portion 21 has a triangular shape (corrugated shape) and a tapered shape.

The ball bearing 20 of the second embodiment can be preferably used when the outer ring rotates. In the case of outer ring rotation, the seal member 16 rotates together with the outer ring 11. At this time, the protrusion 21
Not only reduces the space where grease stays, but also
The grease is agitated with the rotation of the seal member 16 by a stronger stirring action than that of the protrusion 17 of the first embodiment to promote the flow.

In the first embodiment and the second embodiment, the protruding portion separate from the core member 16b is attached, but the protruding portion does not necessarily have to be formed separately. FIG. 5 shows a ball bearing 30 according to the third embodiment of the present invention. The ball bearing 30 of the third embodiment is arranged in the circumferential direction on the inner surface of the seal member (the left seal member in the figure) 16 which is arranged facing the pocket opening side of the crown type cage 15 and is fixedly attached to the outer ring 11. A plurality of protrusions 31 are integrally provided at intervals. The protruding portion 31 includes the seal member 16, the inner and outer rings 11, 12 and the ball 13.
It is arranged in a region S surrounded by and projects toward the ball 13 in parallel to the axial direction.

As shown in FIG. 6A, a plurality of (16 in this case) protrusions 31 are provided at equal intervals in the circumferential direction. In this embodiment, FIG. 4B is a side view.
As shown in FIG. 5, each protrusion 21 has a truncated cone shape and a tapered shape. The protruding portion 31 has a seal member 16
It is molded at the same time when molding. The protruding portion 31 preferably has a tapered shape in consideration of the ease of the extraction process at the time of press working or injection molding. As the material of the core material 16b and the protrusion 31, in addition to the thin steel plate similar to the conventional core metal, a material having good moldability such as plastic is suitable. Although not shown, the seal member 16 is rubber (elastic body)
16a may not be included.

The ball bearing 30 of the third embodiment can be preferably used when the outer ring rotates. In the case of outer ring rotation, the seal member 16 rotates together with the outer ring 11. At this time, the protrusion 31
Not only reduces the space where grease stays, but also
The grease is agitated with the rotation of the seal member 16 by a stronger stirring action than that of the protrusion 17 of the first embodiment to promote the flow.

FIG. 7 shows a ball bearing 4 according to a fourth embodiment of the present invention.
Indicates 0. The ball bearing 40 of the fourth embodiment is the crown type cage 1
A seal member (a seal member on the left side in the figure) which is arranged to face the pocket opening side of 5 and is attached and fixed to the outer ring 11 1
On the inner surface of the rubber member 16a forming the core 6, there are provided a plurality of protrusions 41 having a triangular prism shape at intervals in the circumferential direction.
Is integrally molded into. The protruding portion 41 has a seal member 16
A region S surrounded by the inner and outer rings 11, 12 and the ball 13
It has a function of reducing the area S by being arranged inside and projecting in parallel to the ball 13 in the axial direction. The rubber member 16a is integrally formed with a seal fixing portion 16c fixed to the inner diameter surface of the outer ring 11, a lip portion 16d slidingly contacting the outer diameter surface of the inner ring 12, and a protrusion 41.

As shown in FIG. 8A, a plurality of (here, 12) protrusions 41 are formed in a triangular prism shape and are provided at equal intervals in the circumferential direction. In the present embodiment, as shown in FIG. 8B, which is a cross-sectional view, each protrusion 41 has a triangular shape, and each top is arranged on the ball 13 side. The protrusion 41 is formed at the same time when the seal member 16 is formed. The protruding portion 41 is formed of the rubber member 16
The same synthetic rubber as nitrile rubber, acrylic rubber, silicon rubber, fluorine rubber, etc. is used as the material.

The ball bearing 40 of the fourth embodiment can be preferably used when the outer ring rotates. In the case of outer ring rotation, the seal member 16 rotates together with the outer ring 11. At this time, the protruding portion 41
Not only reduces the space where grease stays, but also
The grease is agitated with the rotation of the seal member 16 by a stronger stirring action than that of the protrusion 17 of the first embodiment to promote the flow.

FIG. 9 shows a ball bearing 50 according to the fifth embodiment of the present invention.
Shown in. As shown in FIG. 9, the ball bearing 50 of the fifth embodiment.
Is circumferentially spaced on the inner surface of a rubber member 16a which constitutes a seal member (left seal member in the figure) 16 which is arranged facing the pocket opening side of the crown type retainer 15 and which is mounted and fixed to the outer ring 11. A plurality of protruding portions 51 having a substantially truncated pyramid shape are integrally formed on the core metal 16b. The projecting portion 51 is arranged in a region S surrounded by the seal member 16, the inner and outer races 11 and 12, and the ball 13, and has a function of reducing the region S by projecting toward the ball 13. The rubber member 16a is integrally formed with a seal fixing portion 16c that is fixed to the inner diameter surface of the outer ring 11, a lip portion 16d that is in sliding contact with the outer diameter surface of the inner ring 12, and a protruding portion 51.

As shown in FIG. 10 (a), a plurality (here, 12) of protrusions 51 are formed in a substantially quadrangular pyramid shape having an arc-shaped portion 51a concentric with the ball 13 at the tip. , Are provided at equal intervals in the circumferential direction. In the present embodiment, as shown in FIG. 10B, which is a cross-sectional view, each protrusion 51 has an arc-shaped portion 51 from the core metal 16b side to the tip.
It is formed in a taper shape toward a. The protrusion 51 is formed at the same time when the seal member 16 is formed. The protruding portion 51 is made of the same synthetic rubber as the rubber member 16a, such as nitrile rubber, acrylic rubber, silicon rubber, and fluororubber.

The ball bearing 50 of the fifth embodiment can be preferably used when the outer ring rotates. In the case of outer ring rotation, the seal member 16 rotates together with the outer ring 11. At this time, the protrusion 51
Since the arc-shaped portion 51a is arranged concentrically with and close to the balls 13, the space in which the grease stays is made smaller, and the sealing member 16 has a stronger stirring action than the protruding portion 17 of the first embodiment. Agitates the grease as it rotates to promote flow.

A ball bearing 60 of a sixth embodiment of the present invention is shown in FIG.
Shown in 1. As shown in FIG. 11, the ball bearing 60 according to the sixth embodiment is a seal member (a left seal member in the figure) which is arranged facing the pocket opening side of the crown type retainer 15 and is fixedly attached to the outer ring 11. On the inner surface of the rubber member 16a forming the core 16, a plurality of protrusions 61 having a triangular pyramid shape are formed integrally with the core metal 16b at intervals in the circumferential direction. Protrusion 6
1 is arranged in a region S surrounded by the seal member 16, the inner and outer races 11 and 12, and the ball 13, and has a function of making the region S small by projecting toward the ball 13. The rubber member 16a is integrally formed with a seal fixing portion 16c fixed to the inner diameter surface of the outer ring 11, a lip portion 16d slidingly contacting the outer diameter surface of the inner ring 12, and a protrusion 61.

As shown in FIG. 12 (a), a plurality (here, 12) of protrusions 61 are formed in a triangular pyramid shape and are provided at equal intervals in the circumferential direction. In this embodiment, as shown in FIG. 12B which is a cross-sectional view, each protrusion 61 has a triangular shape, and each top is arranged on the ball 13 side. The protrusion 61 is formed at the same time when the seal member 16 is formed. The protruding portion 61 is the rubber member 1.
The same synthetic rubber as 6a, such as nitrile rubber, acrylic rubber, silicon rubber, and fluororubber, is used as the material.

The ball bearing 60 of the sixth embodiment can be preferably used when the outer ring rotates. In the case of outer ring rotation, the seal member 16 rotates together with the outer ring 11. At this time, the protrusion 61
Since the top is arranged close to the balls 13, not only the space in which the grease stays is made smaller, but also the grease is stirred with the rotation of the seal member 16 with a stronger stirring action than the protrusion 17 of the first embodiment. And promote flow.

The pair of seal members 16, 16 in the first, second, third, fourth, fifth, and sixth embodiments are different in left and right inner surface form. , There is a mounting direction. Therefore, in consideration of the process of assembling the bearing and the workability at the time of mounting the bearing, which side the opening of the crown type cage 15 faces, that is, the front and back of the bearing can be judged from the appearance. Is preferred. For example, a method of distinguishing a pair of seal members 16, 16 by coloring them differently, a method of marking a part of the seal member 16, a method of judging from the conductivity or magnetism of the seal member 16 or the weight difference, etc. Can be adopted.

FIG. 1 shows a ball bearing 70 according to a seventh embodiment of the present invention.
3 shows. As shown in FIG. 13, a ball bearing 70 of the seventh embodiment is a shaft of a ball 13 and a seal member (the left seal member in the figure) 16 that is arranged so as to face the pocket opening side of the crown type cage 15. The directional interval is smaller than the axial interval between the seal member 16 and the ball 13 which are arranged so as to face the side opposite to the pocket opening side. In this ball bearing 70, the space volume S on the pocket opening side of the crown type cage 15 is smaller than that of the conventional one. Therefore, the grease is unlikely to stay. In addition, in the seventh embodiment, since it is not necessary to provide the protruding portion in the above-described embodiments, the seal member 1
The fluidity of the grease can be improved without changing the shape of No. 6. In addition, the pair of seal members 16, 16
Since there is no mounting directionality in the bearing, it is not necessary to consider the process of assembling the bearing and workability when mounting the bearing.

The present invention is not limited to the above-described embodiment, but can be appropriately modified and improved.
For example, the protrusion may be provided on a non-contact type seal member such as a shield. For example, a ball bearing may be used by rotating the inner ring by providing a protrusion on a seal member fixed to the inner ring. For example, the inner surface of the seal member may be provided with a protrusion that protrudes in a direction inclined with respect to the axial direction. In addition, in the fourth, fifth, and sixth embodiments, synthetic rubber such as nitrile rubber, acrylic rubber, silicon rubber, and fluororubber is used as a material for simultaneously molding the protruding portion on the rubber member. However, a biodegradable resin or the like may be used as the material, or natural rubber may be used.

[0034]

As described above, according to the present invention,
By reducing the volume of the space surrounded by the seal member, the inner and outer rings, and the balls that are opposed to the pocket opening side of the crown type retainer by the protrusion, the fluidity of the grease existing in the reduced space is improved. Further, it is possible to contribute to lubrication, and it is possible to improve the life. Further, according to the present invention, by making the axial distance between the seal member on the pocket opening side of the crown type cage and the ball smaller than the axial distance between the seal member on the counter pocket opening side and the ball, the pocket opening The space volume on the side can be reduced, the fluidity of the grease can be improved without providing a protrusion, and the grease can be contributed to lubrication, and the life can be improved.

[Brief description of drawings]

FIG. 1 is a sectional view showing a first embodiment of the present invention.

FIG. 2A is a front view of the seal member of the first embodiment,
(B) is a side view of (a).

FIG. 3 is a sectional view of a second embodiment.

FIG. 4A is a front view of the seal member according to the second embodiment,
(B) is a side view of (a).

FIG. 5 is a sectional view of a third embodiment.

FIG. 6A is a front view of a seal member according to a third embodiment,
(B) is a side view of (a).

FIG. 7 is a sectional view of a fourth embodiment.

FIG. 8A is a front view of a seal member according to a fourth embodiment,
(B) is the sectional view on the AA line of (a).

FIG. 9 is a sectional view of a fifth embodiment.

FIG. 10A is a front view of a seal member according to a fourth embodiment, and FIG. 10B is a sectional view taken along line BB of FIG.

FIG. 11 is a sectional view of a sixth embodiment.

12A is a front view of the seal member of the fifth embodiment, and FIG. 12B is a sectional view taken along line CC of FIG.

FIG. 13 is a sectional view of a seventh embodiment.

FIG. 14 is a cross-sectional view illustrating a conventional ball bearing.

FIG. 15 is an external view of a crown type cage used for a conventional ball bearing.

[Explanation of symbols]

10, 20, 30, 40, 50, 60, 70 Ball bearing 11 outer ring 12 inner ring 13 balls 15 Crown type cage 16 Seal member 16a rubber member 16b Core bar (core material) 16c Seal fixing part 16d lip part 17, 21, 31, 41, 51, 61 Projection 51a arc shape part

Continued front page    F term (reference) 3J101 AA00 AA01 AA03 AA32 AA42                       AA62 BA73 CA13 EA49 EA63                       FA32 GA01

Claims (12)

[Claims] 1. An inner ring, an outer ring, a crown type retainer arranged between the inner and outer rings, a plurality of balls held by the crown type retainer, and an annular ring provided on both sides in the axial direction of the ball. A ball bearing that is lubricated with grease, and is provided with a protrusion that reduces the space volume surrounded by the seal member on the pocket opening side of the crown type retainer, the inner and outer races, and the balls. Ball bearings that are characterized by being 2. The projecting portion is provided on an inner surface of a seal member on a pocket opening side of the crown-shaped cage.
Ball bearing described in. 3. The ball bearing according to claim 2, wherein the protrusion is provided in a band shape along the circumferential direction of the seal member. 4. The ball bearing according to claim 2, wherein a plurality of the protrusions are provided at intervals in the circumferential direction of the seal member. 5. The ball bearing according to claim 2, wherein the protrusion is integrally formed with the seal member. 6. The ball bearing according to claim 5, wherein the seal member has a core material, and the protrusion is integrally formed with the core material. 7. The ball bearing according to claim 1, wherein the protrusion is made of rubber. 8. The seal member comprises the core member and a rubber member having a lip portion and a seal fixing portion and attached to the core member, and the protrusion is integrally formed with the rubber member. The ball bearing according to claim 1. 9. The ball bearing according to claim 7, wherein the protrusion has a triangular prism shape, and a plurality of protrusions are provided at intervals in the circumferential direction. 10. The protrusion according to claim 7, wherein the protrusion has a substantially truncated pyramid shape having an arc-shaped portion concentric with the ball at the tip, and a plurality of protrusions are provided at intervals in the circumferential direction. Ball bearings. 11. The plurality of protrusions are in the shape of a quadrangular pyramid and are provided at intervals in the circumferential direction.
Ball bearing described in. 12. An inner ring, an outer ring, a crown type cage arranged between the inner and outer rings, a plurality of balls held by the crown type cage, and an annular ring provided on both sides in the axial direction of the ball. And a ball bearing that is lubricated with grease, wherein the axial distance between the seal member on the pocket opening side of the crown type cage and the ball is the same as the seal member on the counter pocket opening side and the ball. A ball bearing characterized by being narrower than the axial distance of.