JP2012122502A - Rolling bearing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rolling bearing capable of effectively utilizing grease.SOLUTION: A rolling bearing 1 comprises an outer ring 2 containing an outer ring raceway surface 21, an inner ring 3 containing an inner ring raceway surface 31, a plurality of balls 4 and a cage 5 for holding the balls 4 circumferentially at predetermined intervals, and is lubricated by grease G. An intermittent oil repellant part 11 which is intermittently provided circumferentially and which has oil repellency with respect to the base oil of the grease G, a grease sump 12 for storing grease G circumferentially and the whole circumference oil repellant 13 which is provided at the entire circumference and has oil repellency with respect to the base oil of the grease G are provided in an annular second area A2 adjacent to a first area A1 containing the outer ring raceway surface 21 successively from the outer ring raceway surface 21 side.

Description

  The present invention relates to a rolling bearing.

  For example, as a bearing for a spindle in a machine tool, an outer ring, an inner ring, balls as a plurality of rolling elements interposed between the outer ring and the inner ring, and these balls are held at predetermined intervals in the circumferential direction. There are rolling bearings with cages. Conventionally, such rolling bearings are lubricated by oil / air lubrication in which a mixed flow of oil and air is introduced into the bearing.

However, in recent years, from the viewpoint of environmental measures, cost reduction, and the like, grease lubrication in which grease is enclosed in the bearing tends to be used in the rolling bearing as described above (for example, see Patent Document 1).
In the case of a rolling bearing by grease lubrication, generally, grease having a capacity of about 10 to 15% of the volume of a bearing space which is an annular shape formed between an inner ring and an outer ring is enclosed.

JP 2008-275037 A (see FIG. 1)

In the case of a rolling bearing using grease lubrication, as described above, grease is enclosed in the bearing, but all of this does not contribute to lubrication. That is, for example, during a running-in operation or the like, a part of the grease is discharged to the outside of the bearing, or a part of the grease in the bearing is stagnant as a surplus grease in a region that is not involved in lubrication.
Therefore, in anticipation of grease that is discharged to the outside of the bearing or stagnated in an area that is not involved in lubrication, more grease than is actually required for lubrication, that is, 10 to 15% of the volume of the bearing space A certain amount of grease is sealed in the bearing.

  In this way, if more grease than necessary is enclosed in the bearing, excess grease moves between the inner ring or outer ring and the rolling element during the familiar operation or the initial stage of actual operation. When it is bitten, the stirring resistance increases rapidly, and the bearing temperature may increase rapidly. In this case, for example, the grease may deteriorate due to heat, or the inner ring may thermally expand to reduce the bearing gap (axial gap or radial gap), which may cause seizure.

  Then, an object of this invention is to provide the rolling bearing which can utilize grease effectively.

  The present invention provides a first raceway having an annular first raceway surface, a second raceway having an annular second raceway surface facing the first raceway surface, and the first raceway. A plurality of rolling elements interposed between a surface and the second raceway surface, and a cage holding the plurality of rolling elements at a predetermined interval in the circumferential direction, and the first raceway surface and A rolling bearing in which a gap between the second raceway surface and the rolling element is lubricated by grease, and the first raceway surface side in an annular region adjacent to the region where the first raceway surface is formed. In order, the intermittent oil-repellent portion provided intermittently along the circumferential direction and having oil repellency to the base oil of the grease, the grease reservoir portion where the grease is accumulated along the circumferential direction, and the entire circumference And an all-around oil-repellent part having oil repellency with respect to the base oil of the grease. And wherein the Rukoto.

According to the present invention, the grease stored in the grease reservoir can be prevented from being discharged to the outside of the bearing by the entire circumferential oil repellent portion provided over the entire circumference in the first race. And the said grease can flow to the 1st track surface from between the intermittent oil repellent parts provided intermittently, and grease can be supplied intensively between the 1st track surface and a rolling element.
As a result, it is possible to prevent the grease from being discharged to the outside of the bearing, and to suppress a part of the grease from flowing and stagnating in a region not involved in lubrication, so that the grease can be used effectively.

In addition, the rolling bearing is intermittently provided in the annular region adjacent to the region where the second raceway surface is formed in order from the second raceway surface side along the circumferential direction, and the grease base is provided. A second intermittent oil repellent portion having oil repellency to the oil, a second grease reservoir portion in which the grease is accumulated along the circumferential direction, and a whole oil repellent portion that is repellent to the base oil of the grease. It is preferable to have the 2nd all-around oil-repellent part which has oiliness.
In this case, in the second race, the grease stored in the grease reservoir can be prevented from being discharged to the outside of the bearing by the second oil repellent portion provided around the entire circumference. Then, the grease flows from between the second intermittently oil repellent portions provided intermittently to the second raceway surface, and the grease is intensively supplied between the second raceway surface and the rolling elements. Can do.
As a result, it is possible to prevent the grease from being discharged to the outside of the bearing on both the first track ring side and the second track ring side, and to prevent a part of the grease from flowing and stagnating in a region not involved in lubrication. The grease can be used effectively.

Moreover, it is preferable that the initial filling amount of the grease is a capacity of 5% or more and 9% or less of a volume of a bearing space which is an annular shape formed between the first raceway ring and the second raceway ring. .
In this case, the capacity of the grease is small as compared with the conventional case, and it is possible to suppress a part of the grease from remaining in a region that is not involved in lubrication as surplus grease. For this reason, it is possible to prevent surplus grease from moving between the race (outer ring and inner ring) and the rolling elements, as in the past, steeply increasing the agitation resistance and rapidly increasing the bearing temperature. Become. Moreover, sufficient lubrication becomes possible by making the initial sealing amount 5% or more.
The volume of the bearing space is the volume of the space obtained by removing the volumes of the rolling elements and the cage from the annular space formed between the first and second race rings.

  The rolling bearing may be an inner ring in which the first bearing ring is an outer ring and the second bearing ring is provided concentrically on the inner peripheral side of the outer ring via the rolling element. . In this case, an intermittent oil repellent part, a grease reservoir part, and an all-around oil repellent part are provided on the outer ring side. And since the grease which exists between an inner ring | wheel and an outer ring | wheel tends to gather on the outer ring | wheel side, this structure can use grease effectively.

  Further, the rolling bearing is a thrust rolling bearing that supports an axial force, and is formed on an annular region adjacent to the radially outer side of the region where the first raceway surface is formed from the first raceway surface side. The intermittent oil repellent part, the grease reservoir part, and the all-around oil repellent part are provided in order, and the intermittent oil repellent part is sequentially provided in an annular region adjacent to the radially outer side of the first raceway surface from the first raceway surface side. An oil part, a grease reservoir part, and an all-around oil repellent part may be provided. In this case, the grease existing between the first raceway ring and the second raceway ring gathers on the radially outer side with respect to the raceway surface, so that the grease can be effectively used with this configuration.

  Further, the grease reservoir is preferably formed of a concave groove provided over the entire circumference in the circumferential direction. In this case, the grease can be accumulated in the grease reservoir, and a part of the grease escapes to an area not involved in lubrication. Can be prevented.

  According to the present invention, the grease stored in the grease reservoir is prevented from being discharged to the outside of the bearing, and a part of the grease is prevented from flowing and stagnating in an area not involved in lubrication, thereby effectively using the grease. Can be used.

It is a schematic sectional drawing of the rolling bearing of this invention. It is explanatory drawing which expand | deployed the outer ring | wheel, and has shown the inner peripheral surface. It is a schematic sectional drawing of the rolling bearing which concerns on 2nd Embodiment. It is explanatory drawing which expand | deployed the inner ring | wheel and has shown the outer peripheral surface. It is a schematic sectional drawing of the rolling bearing which concerns on 3rd Embodiment. It is a schematic sectional drawing of the rolling bearing which concerns on 4th Embodiment. It is explanatory drawing which looked at the inner surface (outer peripheral surface of the inner ring) of the outer ring from the axial direction. It is a schematic sectional drawing of the rolling bearing which concerns on 5th Embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic sectional view showing an embodiment of a rolling bearing according to the present invention. This rolling bearing 1 holds an outer ring 2 (first bearing ring), an inner ring (second bearing ring) 3, a plurality of balls (rolling elements) 4 arranged therebetween, and these balls 4. The retainer 5 is provided. The rolling bearing 1 of this embodiment is an angular ball bearing.

The rolling bearing according to the present invention is used particularly in a high-speed rotation environment, and can, for example, rotatably support a spindle of a machine tool. The rolling bearing of the present invention is lubricated by the grease G provided between the outer ring 2 and the inner ring 3.
The grease G is a mixture of a base oil with a thickener and an additive, and may be a charing type, but is a channeling type in the present embodiment. Various greases can be used as the grease G, for example, urea grease based on ester oil. As will be described later, the grease G is provided in an annular shape along the grease reservoir 12 formed on the inner peripheral surface 20 of the outer ring 2, and the entire circumferential oil repellent provided on the inner peripheral surface 20. Outflow to the outside is prevented by the portion 13.

The outer ring 2 is formed in an annular shape, and an annular outer ring raceway surface (first raceway surface) 21 is formed on the inner circumference of the outer ring 2 over the entire circumferential direction. The outer ring raceway surface 21 has a groove shape.
Further, the inner ring 3 is also formed in an annular shape, and an annular inner ring raceway surface (second raceway surface) 31 is formed on the outer periphery of the inner ring 3 over the entire circumference, and the inner ring raceway surface 31 has a groove shape. The inner ring 3 is provided concentrically on the inner peripheral side of the outer ring 2 via a plurality of balls 4, and the outer ring raceway surface 21 and the inner ring raceway surface 31 are opposed to each other with the ball 4 interposed therebetween. That is, a plurality of balls 4 are interposed between the outer ring raceway surface 21 and the inner ring raceway surface 31, and the plurality of balls 4 are held by the cage 5 at equal intervals in the circumferential direction.

FIG. 2 is an explanatory view in which the outer ring 2 is developed, and shows an inner peripheral surface 20 thereof. The horizontal direction in FIG. 2 is a direction parallel to the rotation center (axial center) of the bearing, and the vertical direction in FIG. 2 is a direction along the circumferential direction of the outer ring 2.
In FIG. 2, an outer ring raceway surface 21 is formed in a first area A <b> 1 in the center of the inner peripheral surface 20 of the outer ring 2. The left and right sides of the outer ring 2 in FIG. 2 are “outside” on both sides in the axial direction of the bearing, and the “outer” side is referred to as the axially outer side with reference to the outer ring raceway surface 21 (first region A1).

  On the inner peripheral surface 20 of the outer ring 2, the region on the one side (left side in FIG. 2) of the outer side in the axial direction of the outer ring raceway surface 21 is the second region A2, and the region on the other side (right side in FIG. 2) is the region. The third region A3. Each of the second region A2 and the third region A3 is an annular region adjacent to the first region A1 where the outer ring raceway surface 21 is formed.

[1. First Embodiment]
The outer ring 2 of the embodiment shown in FIGS. 1 and 2 has oil repellency with respect to the base oil of the grease G in the second region A2 in order from the first raceway surface 21 (first region A1) side. It has the intermittent oil-repellent part 11 which has, the grease reservoir part 12 in which the grease G is collected along the circumferential direction, and the all-around oil-repellent part 13 which has oil repellency with respect to the base oil of the grease G.
That is, among the inner peripheral surface 20 of the outer ring 2 where the outer ring raceway surface 21 is formed (the annular surface of the outer ring 2), a second annular region different from the first region A1 where the outer ring raceway surface 21 is formed. An intermittent oil-repellent part 11, a grease reservoir part 12, and an all-around oil-repellent part 13 are provided in A2 in order from the outer ring raceway surface 21 side.

The grease reservoir 12 is a portion in which the grease G is accumulated along the circumferential direction. In the present embodiment, the grease reservoir 12 includes a concave groove (see FIG. 1), and the concave groove is along the circumferential direction. It is continuously formed in an annular shape.
In the present embodiment (the same applies to the following embodiments), the groove that constitutes the grease reservoir 12 and the intermittent oil repellent portion 11 are continuously provided without a gap, and the grease reservoir 12 is also provided continuously between the concave groove constituting 12 and the all-round oil-repellent portion 13 without a gap. Although not shown, a gap (the base of the outer ring 2 is exposed) between the concave groove and the intermittent oil repellent part 11 and between the concave groove and the entire circumferential oil repellent part 13. Part) may be formed. In this case, the gap is included in the grease reservoir 12.

  The intermittent oil repellent portion 11 is provided intermittently along the circumferential direction on the inner peripheral surface 20 of the outer ring 2. That is, the intermittent oil-repellent portion 11 has a long band shape along the circumferential direction, and a plurality of intermittent oil-repellent portions 11 are provided with a circumferential gap g1. The circumferential dimension of the gap g1 is about 0.2 mm to 1 mm. The grease G provided in the grease reservoir 12 can flow from the gap g1 formed in the circumferential direction to the outer ring raceway surface 21 as indicated by an arrow, and other than the gap g1. From the region (on the intermittent oil repellent portion 11), the grease G cannot flow to the outer ring raceway surface 21 side.

The entire circumferential oil repellent portion 13 is provided on the inner circumferential surface 20 of the outer ring 2 over the entire circumference. That is, unlike the intermittent oil repellent part 11, the entire circumferential oil repellent part 13 is provided without a gap along the circumferential direction.
Although the width dimension (width dimension in the direction parallel to the rotation center of the bearing) of the intermittent oil repellent part 11 and the entire circumferential oil repellent part 13 can be changed according to the size of the bearing, for example, 1.0 mm to 2.0 mm. It is. In the case of a bearing having an inner diameter of 50 to 100 mm, the width dimension is preferably about 10 to 20% of the shoulder width or the width of the second region A2.

  In the rolling bearing 1 of the present embodiment, as shown in FIG. 1, the straight line connecting the contact points of the outer ring 2 and the inner ring 3 and the ball 4 has an inclination angle (contact angle) with respect to the radial direction. The outer ring 2 has a large-diameter inner peripheral surface (second region A2) having a large diameter on one side in the axial direction with the outer ring raceway surface 21 sandwiched between the inner ring 20 and the outer ring 2. A small-diameter inner peripheral surface (third region A3) having a smaller diameter than the above-mentioned ones, and the large-diameter inner peripheral surface (second region A2) includes an intermittent oil-repellent portion 11, a grease reservoir portion 12, and An all-round oil-repellent portion 13 is provided. As a result, the cage 5 is prevented from slidingly contacting the intermittent oil-repellent portion 11, the grease reservoir portion 12, and the entire circumferential oil-repellent portion 13.

The intermittent oil-repellent part 11 and the all-round oil-repellent part 13 may be of different types, but in the present embodiment, they are of the same type. Each of the intermittent oil repellent part 11 and the entire circumferential oil repellent part 13 is made of an oil repellent having oil repellency with respect to the base oil of the grease G, and the oil repellent is applied to the inner peripheral surface 20 of the outer ring 2 and dried. Thus, an oil repellent film is obtained.
More specifically, a fluorine compound or silicon oil can be used as the oil repellent. For example, a solvent in which a fluorosurfactant is diluted as the oil repellent is used for the outer ring 2 subjected to the oil repellent treatment. An oil repellent film is formed on the inner peripheral surface 20 by, for example, applying a mask and spraying, and then drying the solvent. The oil repellent film is used as the intermittent oil repellent portion 11 and the entire peripheral oil repellent portion 13. .

According to the rolling bearing 1 according to the first embodiment having the above configuration, on the inner peripheral surface 20 of the outer ring 2, the intermittent oil repellent portion 11, the grease reservoir portion 12, and the entire peripheral repellent portion are sequentially arranged from the outer ring raceway surface 21 side. The oil portion 13 is provided.
The grease G stored in the grease reservoir 12 can be prevented from being discharged to the outside of the bearing by the entire circumferential oil-repellent portion 13 provided outward in the axial direction. Then, the grease G stored in the grease reservoir 12 is controlled by the intermittent oil repellent portion 13 and flows intensively from between the intermittent oil repellent portions 11 (the gap g1) to the outer ring raceway surface 21. The grease G can be stably supplied over a long period between the outer ring raceway surface 21 and the balls 4.

As a result, the grease G can be prevented from being discharged to the outside of the bearing, and a part of the grease G can be prevented from flowing and stagnating as a surplus grease in an area not involved in lubrication, so that the grease G can be used effectively. Thus, it becomes possible to eliminate the need for a large amount of grease G that causes surplus.
In particular, in the present embodiment, when the rolling bearing 1 is manufactured, the capacity of the grease G sealed between the outer ring 2 and the inner ring 3, that is, the initial amount of grease G provided in the grease reservoir 12 is 5 to 9% of the volume of the annular bearing space formed between the inner ring 3 and the inner ring 3, and the grease capacity is smaller than the conventional 10 to 15%. The volume of the bearing space is a space obtained by removing the volumes of the balls 4 and the cage 5 from an annular space formed between the inner peripheral surface 20 of the outer ring 2 and the outer peripheral surface 30 of the inner ring 3. Is the volume.
Thus, by setting the capacity to 5% or more, sufficient lubrication is possible in the rolling bearing 1, and by setting the capacity to 9% or less, a part of the grease G filled in the grease reservoir 12 is obtained. However, it can suppress staying in the area | region which does not participate in lubrication as an excess grease. As a result, it is possible to prevent surplus grease from moving between the outer ring 2 or the inner ring 3 and the balls 4 as in the prior art, steeply increasing the agitation resistance, and rapidly increasing the bearing temperature.

[2. Second Embodiment]
FIG. 3 is a schematic cross-sectional view of a rolling bearing according to the second embodiment. The second embodiment is the same as the first embodiment except for the inner ring 3. That is, the outer ring 2 has a first oil repellency with respect to the base oil of the grease G in order from the first raceway surface 21 (first region A1) side in the second region A2 as in the first embodiment. The intermittent oil repellency portion 11, the first grease reservoir portion 12 in which the grease G is accumulated along the circumferential direction, and the first entire circumferential oil repellency portion 13 having oil repellency with respect to the base oil of the grease G. Have.

And the inner ring | wheel 3 is formed in cyclic | annular form, the cyclic | annular inner ring raceway surface (2nd raceway surface) 31 is formed in the outer periphery over the circumferential direction, and the inner ring raceway surface 31 is groove shape.
FIG. 4 is an explanatory view in which the inner ring 3 is developed, and shows an outer peripheral surface 30 thereof. The horizontal direction in FIG. 3 is a direction parallel to the rotation center (axial center) of the bearing, and the vertical direction in FIG. 3 is a direction along the circumferential direction of the inner ring 3.

The inner ring 3 has an oil repellent property with respect to the base oil of the grease G in order from the inner ring raceway surface 31 side in the annular second region B2 adjacent to the first region B1 where the inner ring raceway surface 31 is formed. Two intermittent oil repellent portions 16, a second grease reservoir portion 17 in which the grease G is accumulated along the circumferential direction, and a second entire circumferential oil repellent portion 18 having oil repellency with respect to the base oil of the grease G. have.
That is, of the outer peripheral surface 30 of the inner ring 3 on which the inner ring raceway surface 31 is formed (the annular surface of the inner ring 3), the second annular region B2 that is different from the first region B1 on which the inner ring raceway surface 31 is formed. In addition, a second intermittent oil repellent portion 16, a second grease reservoir portion 17, and a second all-around oil repellent portion 18 are provided in this order from the inner ring raceway surface 31 side.

The second grease reservoir 17 is a portion in which the grease G is accumulated along the circumferential direction. In this embodiment, the grease reservoir 17 is a concave groove (see FIG. 3), and the concave groove is circumferential. Are continuously formed in an annular shape.
The second intermittent oil repellent portion 16 is provided intermittently on the outer peripheral surface 30 of the inner ring 3 along the circumferential direction. That is, the second intermittent oil repellent portion 16 has a long band shape along the circumferential direction, and a plurality of second intermittent oil repellent portions 16 are provided with a circumferential gap g2. Then, the grease G provided in the grease reservoir 17 can flow from the gap g2 formed in the circumferential direction to the inner ring raceway surface 31 as indicated by the arrows, and other than the gap g2. From the region (on the intermittent oil repellent portion 16), the grease G cannot flow to the inner ring raceway surface 31 side.

  The second entire circumferential oil repellent portion 18 is provided on the outer circumferential surface 30 of the inner ring 3 over the entire circumference. That is, unlike the second intermittent oil-repellent portion 16, the second all-around oil-repellent portion 18 is provided without a gap along the circumferential direction.

  Further, as shown in FIG. 3, the inner ring 3 has a small-diameter outer peripheral surface (second region B <b> 2) having a small diameter on one side in the axial direction with the inner ring raceway surface 31 sandwiched between the outer peripheral surface 30 and the outer ring 30. Has a large-diameter outer peripheral surface (third region B3) having a large diameter, and among these, the intermittent oil-repellent portion 16, the grease reservoir portion 17 and the entire peripheral oil-repellent portion are provided on the small-diameter outer peripheral surface (second region B2). A portion 18 is provided. As a result, the cage 5 is prevented from slidingly contacting the intermittent oil repellent portion 16, the grease reservoir portion 17 and the entire circumferential oil repellent portion 18.

The second intermittent oil repellent part 16 and the second all-around oil repellent part 18 are the same as those formed in the outer ring 2 and are made of an oil repellent having oil repellent properties with respect to the base oil of the grease G, The description is omitted.
According to the rolling bearing according to the second embodiment, as in the first embodiment, the first intermittent oil repellent portion 11 and the first grease reservoir portion 12 are sequentially arranged on the outer ring 2 side from the outer ring raceway surface 21 side. And the first all-round oil-repellent portion 13 are provided, and the second intermittent oil-repellent portion 16, the second grease reservoir portion 17, and the inner ring 3 side are also sequentially arranged from the inner ring raceway surface 31 side. The second circumferential oil repellent portion 18 is provided.

For this reason, also on the inner ring 3 side, the grease G stored in the grease reservoir 17 is prevented from being discharged to the outside of the bearing by the entire peripheral oil-repellent portion 18 provided on the outer side in the axial direction. Can do. Then, the grease G stored in the grease reservoir 17 is controlled by the intermittent oil repellent portion 16 and flows intensively from between the intermittent oil repellent portions 16 (the gap g2) to the inner ring raceway surface 31, The grease G can be stably supplied over a long period between the inner ring raceway surface 31 and the balls 4.
As a result, in both the inner ring 3 and the outer ring 2, the grease G is prevented from being discharged to the outside of the bearing, and a part of the grease G is prevented from flowing and stagnation as a surplus grease in a region not involved in lubrication. The grease G can be used effectively, and it is possible to eliminate the need for such a large amount of grease that a surplus occurs.

  In the second embodiment, not only the outer ring 2 side but also the inner ring 3 side are provided with grease reservoirs 12 and 17 that accumulate grease G. Therefore, the sum of the initial amount of grease G charged on the outer ring 2 side and the initial amount of grease G charged on the inner ring 3 side is the volume of the bearing space that is an annular shape formed between the outer ring 2 and the inner ring 3. The capacity is 5% or more and 9% or less.

  In each of the first and second embodiments described above, the first race ring is the outer ring 2, and the second race ring is provided concentrically on the inner peripheral side of the outer ring 2 via a plurality of balls 4. 3 and (at least) an intermittent oil repellent part, a grease reservoir part, and an all-around oil repellent part are provided on the outer ring 2 side. And the grease G which exists between the inner ring | wheel 3 and the outer ring | wheel 2 is easy to gather on the outer ring | wheel 2 side, if a rolling bearing rotates. Therefore, according to the configuration of each of the first and second embodiments, the grease G collected on the outer ring 2 side can be effectively used.

[3. Third Embodiment]
A rolling bearing according to the present invention includes a first bearing ring in which an annular first raceway surface is formed, and a second bearing ring in which an annular second raceway surface facing the first raceway surface is formed. An intermittent oil repellent part, a grease reservoir part, and an all-around oil repellent part are provided on the first track ring side.
In each of the first and second embodiments, the case where the first track ring is the outer ring 2 and the second track ring is the inner ring 3 has been described.

On the other hand, in the third embodiment (see FIG. 5), the first track ring is the inner ring 3, the second track ring is the outer ring 2, and only the inner ring 3 side is the same as the second embodiment. In addition, an intermittent oil repellent part 16, a grease reservoir part 17 and an all-around oil repellent part 18 are provided.
That is, in the third embodiment, the balls 4, the cage 5 and the inner ring 3 as the rolling elements are the same as in the second embodiment, and the outer ring 2 becomes an oil repellent part and a grease reservoir part. A concave groove is not formed. Since the structure of each part of the inner ring 3 is the same as each structure of the second embodiment, description thereof is omitted.

According to the rolling bearing of the third embodiment, on the inner ring 3 side, the grease G stored in the grease storage portion 17 is fed to the outside of the bearing by the entire circumferential oil-repellent portion 18 provided outward in the axial direction. Can be prevented from being discharged. The grease G stored in the grease reservoir 17 flows intensively from the interval between the intermittent oil repellent portions 16 to the inner ring raceway surface 31 as controlled by the intermittent oil repellent portion 16. The grease G can be stably supplied between the balls 4 over a long period of time.
As a result, on the inner ring 3 side, the grease G is prevented from being discharged to the outside of the bearing, and a part of the grease G is prevented from flowing and stagnating as a surplus grease in an area not involved in lubrication. It is possible to use a lot of grease that can be used and generates excess.

[4. Fourth Embodiment]
As described above, the rolling bearing of the present invention includes the first race ring in which the annular first raceway surface is formed, and the second raceway in which the annular second raceway surface facing the first raceway surface is formed. An intermittent oil-repellent part, a grease reservoir part, and an all-around oil-repellent part are provided on the first track ring side.
The rolling bearing (FIG. 6) according to the fourth embodiment has a disk shape in which the first and second race rings are arranged in the axial direction (vertical direction in FIG. 6) via a plurality of balls 4. A thrust rolling bearing made of a member and supporting at least an axial force. FIG. 6 is a schematic cross-sectional view of a rolling bearing according to the fourth embodiment.

Here, the first race ring is referred to as an outer ring 7, and the second race ring is referred to as an inner ring 8, and the inner race 8 is fitted on a shaft (not shown), and the inner race 8 rotates with respect to the outer ring 7 together with the shaft. To do.
The outer ring 7 is formed in an annular disk, and an annular outer ring raceway surface (first raceway surface) 26 is formed on the inner side surface 7a over the entire circumference in the circumferential direction. The outer ring raceway surface 26 has a groove shape. .
The inner ring 8 is formed in an annular disk, and an inner ring raceway surface (second raceway surface) 36 is formed on the inner side surface 8a over the entire circumference in the circumferential direction. It is.
The outer ring raceway surface 26 and the inner ring raceway surface 36 face each other with the ball 9 interposed therebetween. That is, a plurality of balls 9 are interposed between the outer ring raceway surface 26 and the inner ring raceway surface 36, and the plurality of balls 9 are held by the cage 10 at equal intervals in the circumferential direction.

FIG. 7 is an explanatory view of the inner surface 7a of the outer ring 7 as viewed from the axial direction. The region in the radially outward direction of the first region E1 where the outer ring raceway surface 26 is formed is the second region E2, and the region in the radially inward direction is the third region E3. The second region E2 and the third region E3 are annular regions adjacent to the first region E1 where the outer ring raceway surface 26 is formed.
The outer ring 7 according to the present embodiment includes an intermittent oil-repellent portion 51 having oil repellency with respect to the base oil of the grease G and grease in which the grease G is stored in order from the outer ring raceway surface 26 side in the annular second region E2. A reservoir 52 and an all-round oil-repellent portion 53 having oil repellency with respect to the base oil of the grease G are provided.

  The grease reservoir 52 is a portion in which the grease G is accumulated along the circumferential direction. In the present embodiment, the grease reservoir 52 includes a concave groove (see FIG. 6), and the concave groove is along the circumferential direction. It is formed continuously.

  The intermittent oil repellent portion 51 is provided intermittently along the circumferential direction on the inner peripheral surface 20 of the outer ring 2. That is, the intermittent oil-repellent portion 51 has a long arc-shaped belt shape along the circumferential direction, and a plurality of intermittent oil-repellent portions 51 are provided with a circumferential gap g3. The grease G provided in the grease reservoir 52 can flow from the gap g3 formed in the circumferential direction to the outer ring raceway surface 26 as indicated by an arrow, and other than the gap g3. From the region (on the intermittent oil repellent portion 51), the grease G cannot flow to the outer ring raceway surface 26 side.

The entire circumferential oil repellent portion 53 is provided on the inner side surface 7 a of the outer ring 7 over the entire circumference. That is, unlike the intermittent oil repellent part 51, the entire circumferential oil repellent part 53 is provided without a gap along the circumferential direction.
The intermittent oil-repellent part 51 and the all-round oil-repellent part 53 are the same as those in the above-described embodiments, and are composed of an oil-repellent agent that has oil-repellency with respect to the base oil of the grease G, and the description thereof is omitted.

According to the rolling bearing of the present embodiment, the grease G stored in the grease reservoir 52 is prevented from being discharged to the outside of the bearing by the entire circumferential oil-repellent portion 53 provided in the radially outward direction. Can do. Then, the grease G stored in the grease reservoir 52 is controlled by the intermittent oil repellent portion 51 and flows intensively from between the intermittent oil repellent portions 51 (the gap g3) to the outer ring raceway surface 26. The grease G can be stably supplied over a long period between the outer ring raceway surface 26 and the balls 9.
As a result, the grease G can be prevented from being discharged to the outside of the bearing, and a part of the grease G can be prevented from flowing and stagnating as a surplus grease in an area not involved in lubrication, so that the grease G can be used effectively. Therefore, it becomes possible to eliminate the need for a lot of grease to generate surplus.
In particular, the grease G existing between the outer ring 7 and the inner ring 8 gathers on the radially outer side with respect to the outer ring raceway surface 26, so that the grease can be effectively used with this configuration.

  In addition, when the rolling bearing is manufactured, the capacity of the grease G sealed between the outer ring 7 and the inner ring 8, that is, the initial amount of grease G provided in the grease reservoir 52 is determined by the outer ring 7 and the inner ring 8. 5 to 9% of the volume of the annular bearing space formed between them, and the capacity of grease is smaller than the conventional 10 to 15%. Thus, by setting the capacity to 5% or more, sufficient lubrication is possible in the rolling bearing, and by setting the capacity to 9% or less, a part of the grease G filled in the grease reservoir 52 is obtained. In addition, it is possible to suppress stagnation in a region that does not participate in lubrication as surplus grease. As a result, it is possible to prevent surplus grease from moving between the outer ring 7 or the inner ring 8 and the ball 9 as in the prior art, steeply increasing the agitation resistance, and rapidly increasing the bearing temperature.

[5. Fifth Embodiment]
FIG. 8 is a schematic cross-sectional view of a rolling bearing according to the fifth embodiment. The fifth embodiment is the same as the fourth embodiment except for the inner ring 8. That is, the outer ring 7 has a first oil repellency with respect to the base oil of the grease G in order from the first raceway surface 26 (first region E1) side in the second region E2, as in the fourth embodiment. The intermittent oil repellent part 51, the first grease reservoir 52 in which the grease G is accumulated along the circumferential direction, and the first all-round oil repellent part 53 having oil repellency with respect to the base oil of the grease G. Have.

The inner ring 8 is formed in an annular shape, and an annular inner ring raceway surface (second raceway surface) 36 is formed on the inner side surface 8a over the entire circumference in the circumferential direction. The inner ring raceway surface 36 has a groove shape.
The inner ring 8 has oil repellency with respect to the base oil of the grease G in order from the inner ring raceway surface 36 side in the annular second region F2 adjacent to the first region F1 where the inner ring raceway surface 36 is formed. Two intermittent oil repellent portions 56, a second grease reservoir portion 57 in which the grease G is accumulated along the circumferential direction, and a second entire circumferential oil repellent portion 58 having oil repellency with respect to the base oil of the grease G. have.

An explanatory view of the inner surface 8a of the inner ring 8 viewed in the axial direction is the same as FIG. 7, and when described with reference to FIG. 7, the second grease reservoir 57 stores the grease G along the circumferential direction. In this embodiment, the grease reservoir 57 is formed of a concave groove (see FIG. 8), and the concave groove is continuously formed in an annular shape along the circumferential direction.
The second intermittent oil repellent portion 56 is provided intermittently on the inner side surface 8a of the inner ring 8 along the circumferential direction. That is, the second intermittent oil-repellent portion 56 has a long arc-shaped band shape along the circumferential direction, and a plurality of the second intermittent oil-repellent portions 56 are provided with a gap in the circumferential direction. The grease G provided in the grease reservoir 57 can flow from the gap formed in the circumferential direction to the inner ring raceway surface 36, and a region other than the gap (on the intermittent oil repellent portion 56). The grease G cannot flow to the inner ring raceway surface 36 side.

The second entire circumferential oil repellent portion 58 is provided on the inner side surface 8 a of the inner ring 8 over the entire circumference. That is, unlike the second intermittent oil repellent part 56, the second all-around oil repellent part 58 is provided without a gap along the circumferential direction.
The second intermittent oil repellent part 56 and the second all-round oil repellent part 58 are the same as those formed on the outer ring 7 and are made of an oil repellent having oil repellent property with respect to the base oil of the grease G, The description is omitted.
In the present embodiment, the sum of the initial amount of grease G on the outer ring 7 side and the initial amount of grease G on the inner ring 8 side is an annular shape formed between the outer ring 7 and the inner ring 8. The capacity is 5% to 9% of the volume of the bearing space.

According to the rolling bearing according to the fifth embodiment, as in the fourth embodiment, on the outer ring 7 side, the first intermittent oil repellent part 51 and the first grease reservoir 52 are sequentially formed from the outer ring raceway surface 26 side. And the first all-round oil-repellent portion 53, and also on the inner ring 8 side, in order from the inner ring raceway surface 36 side, the second intermittent oil-repellent portion 56, the second grease reservoir 57 and The second circumferential oil repellent portion 58 is provided.
For this reason, also on the inner ring 8 side, the grease G stored in the grease reservoir 57 is prevented from being discharged to the outside of the bearing by the entire circumferential oil-repellent portion 58 provided on the outer side in the axial direction. Can do. The grease G stored in the grease reservoir 57 flows from between the intermittent oil repellent portions 56 to the inner ring raceway surface 36 under the control of the intermittent oil repellent portion 56 and flows intensively. The grease G can be stably supplied between the balls 9 over a long period of time.
As a result, in both the inner ring 8 and the outer ring 7, the grease G is prevented from being discharged to the outside of the bearing, and a part of the grease G is prevented from flowing and stagnation as a surplus grease in a region not involved in lubrication. The grease G can be used effectively, and it is possible to eliminate the need for such a large amount of grease that a surplus occurs.

Although the rolling bearing of each said embodiment was demonstrated as an object for the spindles of a machine tool, it is applicable also to another apparatus.
Further, the rolling bearing of the present invention is not limited to the illustrated form, but may be of another form within the scope of the present invention. For example, although each embodiment according to FIGS. 1 to 5 has been described as an angular roller bearing, it may be a radial roller bearing in which a straight line connecting the contact points between the balls and the inner and outer raceways faces in the radial direction. . Moreover, in each said embodiment, although the rolling element was demonstrated as a ball | bowl, a cylindrical roller may be sufficient.

1: Rolling bearings, 2, 7: Outer ring (first race ring), 3, 8: Inner ring (second race ring), 4, 9: Ball (rolling element), 5, 10: Cage, 11, 16: Intermittent oil repellent part, 12, 17: Grease reservoir part, 13, 18: Whole oil repellent part, 21: Outer ring raceway surface (first raceway surface), 26: Outer ring raceway surface (first raceway surface), 31: Inner ring Raceway surface (second raceway surface), 36: Inner ring raceway surface (second raceway surface), 51, 56: Intermittent oil repellent part, 52, 57: Grease reservoir part, 53, 58: Whole circumferential oil repellent part, G: Grease

Claims (6)

A first raceway having an annular first raceway surface; a second raceway having an annular second raceway surface facing the first raceway surface; the first raceway surface and the first raceway. A plurality of rolling elements interposed between two raceway surfaces, and a cage that holds the plurality of rolling elements at a predetermined interval in the circumferential direction, the first raceway surface and the second raceway surface A rolling bearing lubricated with grease between the raceway surface and the rolling element,
In an annular region adjacent to the region where the first track surface is formed, in order from the first track surface side,
An intermittent oil-repellent portion provided intermittently along the circumferential direction and having oil repellency with respect to the base oil of the grease;
A grease reservoir for storing the grease along a circumferential direction;
An all-round oil-repellent portion provided over the entire circumference and having oil repellency with respect to the base oil of the grease;
A rolling bearing characterized by comprising: In an annular region adjacent to the region where the second raceway surface is formed, in order from the second raceway surface side,
A second intermittent oil repellent portion provided intermittently along the circumferential direction and having oil repellency with respect to the base oil of the grease;
A second grease reservoir that stores the grease along a circumferential direction;
A second all-round oil-repellent part provided over the entire circumference and having oil repellency with respect to the base oil of the grease;
The rolling bearing according to claim 1, comprising:   3. The initial grease filling amount is a capacity of 5% or more and 9% or less of a volume of a bearing space which is an annular shape formed between the first raceway ring and the second raceway ring. Rolling bearings as described in   4. The first ring raceway is an outer ring, and the second raceway ring is an inner ring provided concentrically on the inner peripheral side of the outer ring via the rolling elements. 5. Rolling bearings as described in A thrust rolling bearing supporting axial force,
The intermittent oil repellent part, the grease reservoir part, and the all-around oil repellent part are arranged in an annular area adjacent to the radially outward direction of the area where the first raceway surface is formed in order from the first raceway surface side. The rolling bearing as described in any one of Claim 1 to 3 provided. The rolling bearing according to any one of claims 1 to 5, wherein the grease reservoir portion is a concave groove provided over the entire circumference in the circumferential direction.

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