JP2021139497A - Rolling bearing, rotary device, and rolling bearing manufacturing method - Google Patents

Abstract

To provide a rolling bearing which can achieve low torque.SOLUTION: A rolling bearing 1 includes: an inner ring 10 and an outer ring 20 arranged coaxially with each other; rolling elements 30 disposed between the inner ring 10 and the outer ring 20; and filling grease 60 disposed between the inner ring 10 and the outer ring 20. The filling grease 60 has a single arc part 61 which extends in an arc form in a circumferential direction around a common axis O of the inner ring 10 and the outer ring 20 at a predetermined position in an axial direction of the common axis O and a radial direction around the common axis O and contacts with one of the inner ring 10 and the outer ring 20. A first end part 61a of the arc part 61 is disposed spaced apart from a second end part 61b of the arc part 61 in the circumferential direction.SELECTED DRAWING: Figure 1

Description

The present invention relates to rolling bearings, rotating equipment and methods for manufacturing rolling bearings.

Conventionally, some rolling bearings hold grease between a pair of raceway rings (inner ring and outer ring). In this type of rolling bearing, the resistance of grease may be a factor in increasing torque. By the way, in rolling bearings, it is desired to reduce the torque for the purpose of power saving of the rotating equipment to be mounted. In particular, there is a strong demand for lower torque in small rolling bearings used in various motors such as fan motors.

Therefore, in order to reduce the torque of the rolling bearing, grease is applied to the axial end of the fixed ring (in many cases, the outer ring) of the rolling bearing and the seal member arranged on the end side to apply grease to the rolling element (rolling element). The amount of grease that comes into contact with the bearing that holds the ball) and the rolling element is reduced (see, for example, Patent Document 1). In the rolling bearing described in Patent Document 1, the grease adheres to the inner peripheral surface avoiding the raceway surface that contacts the rolling element of the outer ring, and is on the inner peripheral surface side of the outer ring so as not to contact the outer peripheral surface of the inner ring. It is filled in an annular shape with a bias toward.

Japanese Unexamined Patent Publication No. 2013-204679

By the way, as a method of applying grease to a raceway ring in an annular shape, there is a method of relatively rotating the nozzle and the raceway ring while discharging grease from the nozzle. However, when the grease is applied in an annular shape over one round, an overlapping portion is formed between the start point and the end point. The overlapping portion of the grease may gradually collapse due to its own weight and come into contact with the rolling element and the cage more than necessary, and the torque of the rolling bearing may be larger than the desired torque.

Therefore, the present invention provides a rolling bearing, a rotating device, and a method for manufacturing a rolling bearing that can achieve low torque.

The rolling bearing of the present invention comprises an inner ring and an outer ring arranged coaxially with each other, a rolling element arranged between the inner ring and the outer ring, and grease arranged between the inner ring and the outer ring. The grease extends in an arc shape in the circumferential direction around the common axis at predetermined positions in the axial direction of the common axis of the inner ring and the outer ring and in the radial direction about the common axis, and the inner ring and the grease are provided. It has a single arc-shaped portion in contact with one of the outer rings, and the first end portion of the arc-shaped portion is arranged at intervals in the circumferential direction with respect to the second end portion of the arc-shaped portion. , Characterized by.

According to the present invention, since a space is provided between the first end portion and the second end portion of the arc-shaped portion, it is possible to suppress the formation of overlapping portions of the arc-shaped portion. As a result, the grease is less likely to collapse due to its own weight. Therefore, it is possible to prevent the grease from coming into contact with the rolling elements and the cage more than necessary. Therefore, it is possible to achieve a low torque of the rolling bearing.
Moreover, since the arcuate portion is unified at predetermined positions in the axial direction and the radial direction, the portion where the arcuate portion is not provided in the circumferential direction is one portion of the distance between the first end portion and the second end portion. Only. Therefore, as compared with the configuration in which the grease is intermittently arranged along the circumferential direction, the number of places where the grease is not arranged in the circumferential direction is reduced, so that the grease is arranged thinly when filling the desired amount of grease. can. Therefore, it is possible to prevent the grease from coming into contact with the rolling elements and the cage more than necessary. Therefore, it is possible to achieve a low torque of the rolling bearing.

In the rolling bearing, one of the inner ring and the outer ring may be provided as a fixed ring.

According to the present invention, since the grease comes into contact with the fixed wheels, it is possible to suppress the action of centrifugal force on the grease when the rolling bearing rotates, and it is possible to prevent the grease from collapsing from the shape immediately after application. Therefore, it is possible to achieve a low torque of the rolling bearing.

In the rolling bearing, one of the inner ring and the outer ring may be the outer ring.

According to the present invention, even if the grease rotates during the rotation of the rolling bearing and centrifugal force acts on the grease, the outer ring regulates the displacement of the grease to the outside in the radial direction. Can be kept. Therefore, it is possible to achieve a low torque of the rolling bearing.

In the rolling bearing, the grease further includes a stringing portion extending from one of the first end portion of the arc-shaped portion and the second end portion of the arc-shaped portion, and the stringing portion is the arc-shaped portion. The first end portion of the arcuate portion and the second end portion of the arcuate portion may be straddled and connected to the first end portion of the arcuate portion and the second end portion of the arcuate portion.

In forming the arc-shaped portion of grease, when the nozzle for which the grease has been discharged is separated from the rolling bearing, the stringing portion may extend from the arc-shaped portion depending on the viscosity of the grease. According to the present invention, the stringing portion is extended from one of the first end portion and the second end portion of the arc-shaped portion, and the stringing portion straddles the distance between the first end portion and the second end portion of the arc-shaped portion. By connecting to the other of the first end and the second end of the arcuate part, the stringer part hangs down and falls from the distance between the first end part and the second end part of the arcuate part. Can be suppressed. As a result, it is possible to prevent the grease from being placed closer to the rolling element and the cage than the desired position. Therefore, it is possible to prevent the grease from coming into contact with the rolling elements and the cage more than necessary. Therefore, it is possible to achieve a low torque of the rolling bearing.

The rolling bearing further includes a sealing member that covers between the inner ring and the outer ring from the outside in the axial direction, and the grease is provided in the circumferential direction at a position different from the arcuate portion in the axial direction and the radial direction. A single other arc-shaped portion extending in an arc shape, connected to the arc-shaped portion, and in contact with the sealing member is further provided, and the first end portion of the other arc-shaped portion is the second end of the other arc-shaped portion. The portions may be arranged at intervals in the circumferential direction.

According to the present invention, when filling a desired amount of grease, the volume of the arc-shaped portion can be reduced by the amount that the arc-shaped portion and other arc-shaped portions are provided, as compared with the case where only the arc-shaped portion is provided. Therefore, by forming the arc-shaped portion before the other arc-shaped portions when applying the grease, it is possible to prevent the arc-shaped portion from collapsing due to its own weight. Further, by providing the other arc-shaped portion, the other arc-shaped portion is supported by the seal member, and the arc-shaped portion is supported not only by one of the inner ring and the outer ring but also by the seal member via the other arc-shaped portion. .. Therefore, the grease as a whole is less likely to collapse from the shape immediately after application due to its own weight.
Moreover, since the other arc-shaped portion is formed so as to provide a space between the first end portion and the second end portion, similarly to the arc-shaped portion, a portion overlapping the other arc-shaped portion is formed. Can be suppressed. As a result, the grease is less likely to collapse due to its own weight.
As described above, it is possible to prevent the grease from coming into contact with the rolling elements and the cage more than necessary. Therefore, it is possible to achieve a low torque of the rolling bearing.

In the rolling bearing, the other arc-shaped portion may straddle the distance between the first end portion of the arc-shaped portion and the second end portion of the arc-shaped portion.

According to the present invention, since the grease is arranged in the entire circumferential direction, the grease can be uniformly arranged in the entire circumferential direction of the rolling bearing. Further, since the first end portion and the second end portion of the arc-shaped portion are continuously supported by the other arc-shaped portions, it is possible to prevent the grease from collapsing due to disturbance or the like.

In the rolling bearing, the sealing member may be mounted on one of the inner ring and the outer ring.

According to the present invention, since one of the inner ring and the outer ring and the seal member are provided so as not to rotate relative to each other, it is possible to prevent the grease in contact with both from being agitated. Therefore, the grease can be kept in the shape immediately after application. Therefore, it is possible to achieve a low torque of the rolling bearing.

In the rolling bearing, the other arc-shaped portion may be arranged on the side opposite to the one of the inner ring and the outer ring in the radial direction with respect to the arc-shaped portion.

According to the present invention, a space for arranging the arc-shaped portion on one side of the inner ring and the outer ring in the radial direction with respect to the other arc-shaped portion is provided as compared with the configuration in which the arc-shaped portion and the other arc-shaped portions are arranged in the axial direction. The arcuate portion can be arranged outside in the axial direction. As a result, it is possible to prevent the grease from coming into contact with the rolling elements and the cage more than necessary. Therefore, it is possible to achieve a low torque of the rolling bearing.

The rolling bearing may further include other grease arranged on the side opposite to the grease in the axial direction with respect to the rolling element.

According to the present invention, the total amount of grease arranged on the bearing can be increased by other greases. Therefore, it is possible to provide a bearing having a long life.

The rotating device of the present invention has a rotating body which is rotatably arranged, a support which rotatably supports the rotating body, and claims 1 to 2 intervening between the rotating body and the support. The rolling bearing according to any one of 6 is provided.

According to the present invention, since the rolling bearing having a low torque is provided, the rotational resistance of the rotating body with respect to the support can be reduced, and the power saving of the rotating device can be achieved.

The method for manufacturing a rolling bearing of the present invention is the above-mentioned method for manufacturing a rolling bearing, wherein grease is discharged from a first nozzle at a first coating position to form the arcuate portion, and the first coating step. It is characterized by comprising a second coating step of discharging grease from a second nozzle different from the first nozzle at a second coating position different from the coating position to form the other arcuate portion.

According to the present invention, the cycle time at each coating position can be shortened. Therefore, the manufacturing efficiency of the bearing can be improved. Further, in the manufacturing method in which grease is applied in an annular shape while rotating the bearing, a mechanism for driving the nozzle in the radial direction with respect to the bearing is not required, so that the structure of the grease application device can be simplified.

According to the present invention, it is possible to provide a rolling bearing, a rotating device, and a method for manufacturing a rolling bearing that can achieve low torque.

It is a top view of the rolling bearing which concerns on 1st Embodiment. FIG. 2 is a cross-sectional view taken along the line II-II of FIG. It is a top view explaining the method of applying grease. It is a top view explaining the method of applying grease. It is a top view of the rolling bearing which concerns on 2nd Embodiment. It is a top view of the rolling bearing which concerns on 3rd Embodiment. FIG. 6 is a cross-sectional view taken along the line VII-VII of FIG. It is sectional drawing of the rolling bearing of 4th Embodiment. It is sectional drawing of the rolling bearing of 5th Embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, the same reference numerals are given to configurations having the same or similar functions. Then, the duplicate description of those configurations may be omitted.

[First Embodiment]
The first embodiment according to the present invention will be described with reference to FIGS. 1 to 8.
FIG. 1 is a plan view of the rolling bearing according to the first embodiment. FIG. 2 is a cross-sectional view taken along the line II-II of FIG. In FIG. 1, a part of each of the seal member 50 and the filled grease 60, which will be described later, is omitted in order to make it easier to see the internal configuration of the rolling bearing 1. Further, in FIG. 2, a member to which the rolling bearing 1 is mounted is shown by a virtual line.

As shown in FIGS. 1 and 2, the rolling bearing 1 includes an inner ring 10 and an outer ring 20 which are raceway rings, a plurality of rolling elements 30, a cage 40, a pair of sealing members 50, and a filling grease 60. It is a ball bearing equipped with. The rolling bearing 1 is provided in a rotating device 2 such as a fan motor. The rotating device 2 includes a shaft 3 (rotating body) rotatably formed around a common axis O, and a housing 4 (supporting body) that is fixedly set to rotatably support the shaft 3. .. The rolling bearing 1 is interposed between the shaft 3 and the housing 4. In the following, the rolling bearing may be simply referred to as a bearing. Further, in the present embodiment, the grease in the state before being filled in the bearing 1 is simply referred to as grease, and the grease in the state of being filled in the bearing 1 by applying the grease is referred to as the filling grease 60.

The inner ring 10 and the outer ring 20 are arranged coaxially with each other so that their respective central axes are arranged on the common axis O. In the present embodiment, the direction in which the common axis O extends is referred to as an axial direction, the direction orthogonal to the common axis O and extending radially from the common axis O is referred to as a radial direction, and the direction orbiting around the common axis O is referred to as a circumferential direction. ..

The inner ring 10 is provided as a rotating wheel. The inner ring 10 is externally inserted into the shaft 3 and fixed to the shaft 3. The outer ring 20 is provided as a fixed ring. The outer ring 20 is fitted into the recess (or through hole) of the housing 4 and is fixed to the housing 4. The outer ring 20 surrounds the inner ring 10 from the outside in the radial direction in a state where an annular space is provided between the outer ring 20 and the inner ring 10. The plurality of rolling elements 30 are arranged between the inner ring 10 and the outer ring 20 and are rotatably held by the cage 40. The cage 40 rotatably holds each of the rolling elements 30 in a state where the plurality of rolling elements 30 are evenly arranged in the circumferential direction. The seal member 50 covers the annular space between the inner ring 10 and the outer ring 20 from the outside in the axial direction.

The outer ring 20 is formed in an annular shape by a metal material such as stainless steel or bearing steel. However, the outer ring 20 is not limited to being made of metal, and may be made of other materials. The outer ring 20 has an outer ring main body 21 whose width along the axial direction is equal to the width along the axial direction of the inner ring 10, and a protruding portion 22 protruding inward in the radial direction from the outer ring main body 21. Have. The protruding portion 22 is formed in a portion of the outer ring main body 21 located at the center in the axial direction. The width of the protrusion 22 along the axial direction is shorter than the width of the outer ring main body 21 along the axial direction and larger than the outer diameter of the rolling element 30.

An outer ring rolling surface 23 that is recessed toward the outside in the radial direction is formed on the inner peripheral surface of the protruding portion 22. The outer ring rolling surface 23 is formed in a hemispherical cross-sectional view along the outer surface of the rolling element 30, and is also formed in an annular shape extending in the circumferential direction over the entire circumference of the inner peripheral surface of the protruding portion 22. There is. The outer ring rolling surface 23 is formed on a portion of the inner peripheral surface of the protruding portion 22 located at the center in the axial direction. The portion of the inner peripheral surface of the protruding portion 22 excluding the outer ring rolling surface 23 extends in the axial direction with a constant inner diameter. The protrusion 22 includes a pair of end faces 22a facing in the axial direction. Each end face 22a extends parallel to both the radial and circumferential directions.

The outer ring main body 21 has a pair of inner peripheral surfaces 21a extending from the outer peripheral edge of each end surface 22a of the protruding portion 22 to the opening edge of the outer ring 20. The portion of each inner peripheral surface 21a located inside in the axial direction is located outside in the radial direction with respect to the portion located outside in the axial direction.

The inner ring 10 is formed in an annular shape by a metal material such as stainless steel or bearing steel. However, the inner ring 10 is not limited to being made of metal, and may be made of other materials. An inner ring rolling surface 11 that is recessed inward in the radial direction is formed on the outer peripheral surface of the inner ring 10. The inner ring rolling surface 11 is formed in a hemispherical cross-sectional view along the outer surface of the rolling element 30, and is also formed in an annular shape extending in the circumferential direction over the entire circumference of the outer peripheral surface. The inner ring rolling surface 11 is formed on a portion of the outer peripheral surface of the inner ring 10 located at the center in the axial direction, and is arranged so as to face the outer ring rolling surface 23 in the radial direction. The portion of the inner peripheral surface of the inner ring 10 excluding the inner ring rolling surface 11 extends in the axial direction with a constant outer diameter.

The plurality of rolling elements 30 are formed in a spherical shape by a metal material such as stainless steel or bearing steel. The plurality of rolling elements 30 are arranged between the outer ring rolling surface 23 and the inner ring rolling surface 11, and are rotatably supported by the outer ring rolling surface 23 and the inner ring rolling surface 11.

The cage 40 is formed of a synthetic resin or a metal material in an annular shape as a whole. The cage 40 is arranged around the common axis O. The cage 40 includes a main body 41 which is formed in an annular shape and is arranged on the other side in the axial direction with respect to the plurality of rolling elements 30, and a pair of claws 42 which rise from the main body 41 in the axial direction. And. The pair of claws 42 rotatably holds one rolling element 30. The pair of claw portions 42 rise in an arc shape from the main body portion 41 toward the tip end so that the distance between them approaches each other. The cage 40 is arranged with a gap between the inner ring 10 and the outer ring 20 so as not to interfere with the inner ring 10 and the outer ring 20. In the present embodiment, the entire cage 40 is located inside the pair of end faces 22a of the protrusions 22 of the outer ring 20 in the axial direction.

The seal member 50 is formed in the shape of an annular plate. The seal member 50 is arranged around the common axis O. The seal member 50 is attached to the outer ring 20. One seal member 50 is arranged on each side of the plurality of rolling elements 30 in the axial direction. The seal member 50 includes a base portion 51 that overlaps the end surface 22a of the protruding portion 22 of the outer ring 20 from the outside in the axial direction, a step portion 52 that extends outward in the axial direction from the inner peripheral edge of the base portion 51, and an axially outer side of the step portion 52. A cover portion 53 projecting inward in the radial direction from the edge of the base portion 51, and a locking portion 54 extending outward in the radial direction and outward in the axial direction from the outer peripheral edge of the base portion 51 are provided. The seal member 50 extends radially so as to straddle at least the center of the rolling element 30 in a plan view. In the present embodiment, the cover portion 53 overlaps the center of the rolling element 30 in a plan view. However, the stepped portion 52 may extend from the inner peripheral edge of the base portion 51 to the outer side in the axial direction and the inner side in the radial direction and overlap the center of the rolling element 30 in a plan view. The inner peripheral edge of the cover portion 53 is arranged with a gap on the outer peripheral surface of the inner ring 10. The outer peripheral edge of the locking portion 54 is locked to the inner peripheral surface 21a of the outer ring main body 21 from the inside in the axial direction. As a result, the seal member 50 is fixed to the outer ring 20.

The filling grease 60 is arranged between the rolling element 30 and the sealing member 50. The filling grease 60 is arranged only on one side in the axial direction with respect to the rolling element 30 in the annular space between the inner ring 10 and the outer ring 20. In the present embodiment, the filling grease 60 is arranged on one side in the axial direction with respect to the rolling element 30. That is, the filling grease 60 is arranged on the side opposite to the main body 41 of the cage 40 with the rolling element 30 sandwiched in the axial direction. The filling grease 60 is arranged in an annular shape in a plan view and is arranged coaxially with the common axis O. The filling grease 60 is in contact with the outer ring 20 provided as a fixed ring and is separated from the inner ring 10 provided as a rotating ring. Further, the filling grease 60 comes into contact with the inner surface of the cover portion 53 of the seal member 50 and is supported by the seal member 50.

The filling grease 60 includes a single arcuate portion 61 extending in an arcuate manner in the circumferential direction at predetermined positions in the axial and radial directions. That is, the arcuate portion 61 extends without interruption without changing the axial and radial positions. The arc-shaped portion 61 extends from the first end portion 61a, which is one peripheral end portion, to the second end portion 61b, which is the other peripheral end portion, by 180 ° or more and less than 360 °. As a result, the first end portion 61a of the arcuate portion 61 is arranged at intervals in the circumferential direction with respect to the second end portion 61b. It is desirable that the distance between the first end portion 61a and the second end portion 61b of the arcuate portion 61 in the circumferential direction is sufficiently narrow as long as the first end portion 61a and the second end portion 61b do not come into contact with each other. For example, the distance between the first end portion 61a and the second end portion 61b of the arcuate portion 61 in the circumferential direction is set to be smaller than the width of the arcuate portion 61 in a plan view. Further, for example, the distance between the first end portion 61a and the second end portion 61b of the arcuate portion 61 in the circumferential direction is set to be smaller than the axial thickness of the arcuate portion 61. The arcuate portion 61 is in contact with the outer ring 20. Specifically, the arc-shaped portion 61 is in contact with a portion of the inner peripheral surface of the protruding portion 22 of the outer ring 20 that is axially outer of the outer ring rolling surface 23. In the illustrated example, the arcuate portion 61 is separated from the seal member 50. However, the arcuate portion 61 may be in contact with the seal member 50.

Next, as a method of manufacturing the bearing 1 of the present embodiment, a method of applying grease will be described.
3 and 4 are plan views illustrating a method of applying grease.
As shown in FIG. 3, the grease is applied in a state where the sealing member 50 is not attached to the outer ring 20. That is, the annular space between the inner ring 10 and the outer ring 20 is opened in the axial direction, and grease is applied in a state where the rolling element 30 and the cage 40 are exposed.

As shown in FIG. 4, grease G is discharged from the nozzle while rotating a nozzle (not shown) about the common axis O with respect to the outer ring 20. At this time, the position of the nozzle is adjusted so that the discharged grease G comes into contact with the axial end portion on the inner peripheral surface of the protruding portion 22 of the outer ring 20. Since the grease G is discharged while rotating the nozzle relative to the outer ring 20, the grease extends in an arc shape. The grease adhering to the outer ring 20 extends less than 360 ° from the start end 71 corresponding to the discharge start point and reaches the end 72 corresponding to the discharge end point. As a result, an arc-shaped portion 61 having a gap between the first end portion 61a and the second end portion 61b is formed.

With the above, the application of grease is completed. After that, the seal member 50 is inserted into the annular space between the inner ring 10 and the outer ring 20 from the outside in the axial direction, and the seal member 50 is attached to the outer ring 20.

As described above, the bearing 1 of the present embodiment contains the filling grease 60 having a single arc-shaped portion 61 extending in an arc shape in the circumferential direction at predetermined positions in the axial and radial directions and in contact with the outer ring 20. Be prepared. The first end portion 61a of the arc-shaped portion 61 is arranged at intervals in the circumferential direction with respect to the second end portion 61b of the arc-shaped portion 61. According to this configuration, since a space is provided between the first end portion 61a and the second end portion 61b of the arcuate portion 61, it is possible to prevent the arcuate portion 61 from being formed with overlapping portions. As a result, the filled grease 60 is less likely to collapse due to its own weight. Therefore, it is possible to prevent the filled grease 60 from coming into contact with the rolling elements 30 and the cage 40 more than necessary. Therefore, the torque of the bearing 1 can be reduced.

Moreover, since the arcuate portion 61 is single at predetermined positions in the axial direction and the radial direction, the first end portion 61a and the second end portion 61b are located where the arcuate portion 61 is not provided in the circumferential direction. There is only one interval. Therefore, as compared with the configuration in which the grease is intermittently arranged along the circumferential direction, the number of places where the grease is not arranged in the circumferential direction is reduced, so that the filling grease 60 is used to fill the desired amount of grease. Can be arranged thinly. Therefore, it is possible to prevent the filled grease 60 from coming into contact with the rolling elements 30 and the cage 40 more than necessary. Therefore, the torque of the bearing 1 can be reduced.

Further, the outer ring 20 which is a raceway ring with which the filling grease 60 comes into contact is provided as a fixed ring. According to this configuration, since the filling grease 60 comes into contact with the fixed wheel, it is possible to suppress the action of centrifugal force on the filling grease 60 when the bearing 1 is rotated, and it is possible to prevent the filling grease 60 from collapsing from the shape immediately after application. .. Therefore, the torque of the bearing 1 can be reduced.

[Second Embodiment]
A second embodiment according to the present invention will be described with reference to FIG. The configuration other than that described below is the same as that of the first embodiment.

FIG. 5 is a plan view of the rolling bearing according to the second embodiment. In FIG. 5, the seal member 50 is not shown in order to make it easier to see the internal configuration of the bearing 1A.
As shown in FIG. 5, the filling grease 60A of the second embodiment includes a stringing portion 63 in addition to the arc-shaped portion 61. The stringing portion 63 straddles the distance between the first end portion 61a and the second end portion 61b of the arc-shaped portion 61. The stringing portion 63 is connected to the first end portion 61a and the second end portion 61b of the arc-shaped portion 61. The stringing portion 63 extends from the second end portion 61b of the arc-shaped portion 61, which corresponds to the end point of grease discharge when forming the arc-shaped portion 61, to a position where it overlaps the first end portion 61a in a plan view in the circumferential direction. It extends while tilting outward in the axial direction. As described above, since the string pulling portion 63 extends while being inclined with respect to the circumferential direction, it is distinguished from the arc-shaped portion 61 extending at a predetermined position in the axial direction and the radial direction. The cross-sectional area of the cross section of the stringing portion 63 (the cross section orthogonal to the circumferential direction) is smaller than the cross-sectional area of the cross section of the arc-shaped portion 61. The stringing portion 63 extends from the connecting portion of the arc-shaped portion 61 with the second end portion 61b while gradually reducing the cross-sectional area of the cross section. The thread pulling portion 63 is in contact with the inner peripheral surface of the protruding portion 22 of the outer ring 20. However, the thread pulling portion 63 may be separated from the outer ring 20.

As described above, in forming the arc-shaped portion 61 of the filled grease 60A, when the nozzle for which the grease has been discharged is separated from the bearing 1A, the cross section is larger than that of the arc-shaped portion 61 due to the high viscosity of the grease. The stringing portion 63 having a small cross-sectional area extends from the second end portion 61b of the arc-shaped portion 61. According to the present embodiment, the stringing portion 63 is extended from the second end portion 61b of the arc-shaped portion 61, and the stringing portion 63 straddles the distance between the first end portion 61a and the second end portion 61b of the arc-shaped portion 61. By connecting to the first end 61a of the arcuate portion 61, it is possible to prevent the stringing portion 63 from hanging down and falling from the distance between the first end portion 61a and the second end portion 61b of the arcuate portion 61. .. As a result, it is possible to prevent the filled grease 60A from being arranged at a position closer to the rolling element 30 and the cage 40 than at a desired position. Therefore, it is possible to prevent the filled grease 60A from coming into contact with the rolling elements 30 and the cage 40 more than necessary. Therefore, it is possible to achieve a low torque of the bearing 1A.

[Third Embodiment]
A third embodiment according to the present invention will be described with reference to FIGS. 6 and 7. The configuration other than that described below is the same as that of the first embodiment.

FIG. 6 is a plan view of the rolling bearing according to the third embodiment. FIG. 7 is a cross-sectional view taken along the line VII-VII of FIG. In FIG. 6, the seal member 50 is not shown in order to make it easier to see the internal configuration of the bearing 1B.
As shown in FIGS. 6 and 7, the filling grease 160 of the third embodiment has a single first arc-shaped portion 161 (arc-shaped portion) extending in an arc shape in the circumferential direction at predetermined positions in the axial direction and the radial direction. ), And a single second arc-shaped portion 162 (another arc-shaped portion) extending in an arc shape in the circumferential direction at a position different from that of the first arc-shaped portion 161 in the axial direction and the radial direction. The first arc-shaped portion 161 and the second arc-shaped portion 162 are formed by applying grease in two portions. The first arc-shaped portion 161 is formed in the same manner as the arc-shaped portion 61, except that the cross-sectional area of the cross section is smaller than that of the arc-shaped portion 61 of the first embodiment. That is, the first end portion 161a of the first arc-shaped portion 161 is arranged at intervals in the circumferential direction with respect to the second end portion 161b.

The second arc-shaped portion 162 extends without interruption without changing the axial and radial positions. The second arc-shaped portion 162 extends 180 ° or more and less than 360 ° from the first end portion 162a, which is one peripheral end portion, to the second end portion 162b, which is the other peripheral end portion. As a result, the first end portion 162a of the second arc-shaped portion 162 is arranged at intervals in the circumferential direction with respect to the second end portion 162b. It is desirable that the distance between the first end portion 162a and the second end portion 162b of the second arc-shaped portion 162 in the circumferential direction is set smaller than the width of the second arc-shaped portion 162 in a plan view. Further, it is desirable that the distance between the first end portion 162a and the second end portion 162b of the second arc-shaped portion 162 in the circumferential direction is set to be smaller than the axial thickness of the second arc-shaped portion 162. The distance between the first end portion 162a and the second end portion 162b of the second arc-shaped portion 162 is displaced in the circumferential direction with respect to the distance between the first end portion 161a and the second end portion 161b of the first arc-shaped portion 161. It is placed in position. As a result, the second arc-shaped portion 162 straddles the distance between the first end portion 161a and the second end portion 161b of the first arc-shaped portion 161 and the first end portion 161a and the second end portion of the first arc-shaped portion 161. It is connected to 161b.

The second arc-shaped portion 162 is separated from the outer ring 20 to which the first arc-shaped portion 161 of the raceway rings comes into contact. The second arc-shaped portion 162 is arranged on the side opposite to the outer ring 20 in the radial direction (that is, inside in the radial direction) with respect to the first arc-shaped portion 161. Specifically, in a plan view, the outer peripheral edge of the second arc-shaped portion 162 is located radially inside the outer peripheral edge of the first arc-shaped portion 161 and the inner peripheral edge of the second arc-shaped portion 162 is the first arc-shaped portion 161. It is located inward in the radial direction from the inner peripheral edge of. The second arc-shaped portion 162 is connected and integrated with the first arc-shaped portion 161 on the outer side in the axial direction. The second arc-shaped portion 162 is supported by the seal member 50 by contacting the surface of the seal member 50 that faces inward in the axial direction. In the present embodiment, the second arc-shaped portion 162 is in contact with the inner surface of the cover portion 53 of the seal member 50.

Next, as a method of manufacturing the bearing 1B of the present embodiment, a method of applying grease will be described. The grease coating method of the present embodiment includes a first coating step, a transporting step, and a second coating step.

The first coating step is performed in a state where the sealing member 50 is not attached to the outer ring 20. That is, the annular space between the inner ring 10 and the outer ring 20 is opened in the axial direction, and grease is applied in a state where the rolling element 30 and the cage 40 are exposed.

In the first coating step, grease is discharged from the first nozzle while rotating the outer ring 20 around the common axis O at the first coating position in the manufacturing apparatus for applying grease. At this time, the position of the first nozzle is adjusted so that the discharged grease comes into contact with the axial end portion on the inner peripheral surface of the protruding portion 22 of the outer ring 20. Since the grease is discharged while rotating the outer ring 20 with respect to the first nozzle, the grease discharged from the first nozzle extends in an arc shape. As a result, the first arc-shaped portion 161 is formed.

In the transfer step, the bearing that has completed the first coating step is transported to a second coating position different from the first coating position in the manufacturing apparatus.

In the second coating step, grease is discharged from a second nozzle different from the first nozzle while rotating the outer ring 20 around the common axis O at the second coating position. At this time, the position of the second nozzle is adjusted so that the discharged grease comes into contact with the first arc-shaped portion 161 from the outside in the axial direction and the inside in the radial direction. Since the grease is discharged while rotating the outer ring 20 with respect to the second nozzle, the grease discharged from the second nozzle extends in an arc shape. As a result, the second arc-shaped portion 162 is formed.

With the above, the application of grease is completed. After that, the bearing 1B is completed by inserting the seal member 50 into the annular space between the inner ring 10 and the outer ring 20 from the outside in the axial direction and mounting the seal member 50 on the outer ring 20. When the second coating step is being performed, it is desirable to perform the first coating step on the next bearing at the first coating position.

As described above, the bearing 1B of the present embodiment has a single arc-shaped portion 161 extending in an arc shape in the circumferential direction at predetermined positions in the axial direction and the radial direction and contacting the outer ring 20, and the axial direction and the diameter. A filling grease 160 having a single second arc-shaped portion 162 extending in an arc shape in the circumferential direction at a position different from that of the first arc-shaped portion 161 in the direction is provided. The first end portion 161a of the first arc-shaped portion 161 is arranged at intervals in the circumferential direction with respect to the second end portion 161b. The first end portion 162a of the second arc-shaped portion 162 is arranged at intervals in the circumferential direction with respect to the second end portion 162b. According to this configuration, it is possible to prevent the formation of overlapping portions of the first arc-shaped portion 161 and the second arc-shaped portion 162, respectively. As a result, the same effect as that of the first embodiment is obtained.

Further, when filling a desired amount of grease, the volume of the first arc-shaped portion 161 is increased by the amount that the first arc-shaped portion 161 and the second arc-shaped portion 162 are provided, as compared with the case where only the first arc-shaped portion is provided. Can be made smaller. Therefore, by forming the first arc-shaped portion 161 before the second arc-shaped portion 162 when applying grease, it is possible to prevent the first arc-shaped portion 161 from collapsing due to its own weight. Further, by providing the second arc-shaped portion 162, the second arc-shaped portion 162 is supported by the seal member 50, and the first arc-shaped portion 161 is attached to the seal member 50 via not only the outer ring 20 but also the second arc-shaped portion 162. Is also supported. Therefore, the filled grease 160 is less likely to collapse from the shape immediately after application due to its own weight as a whole. Therefore, it is possible to prevent the filled grease 160 from coming into contact with the rolling elements 30 and the cage 40 more than necessary. Therefore, the torque of the bearing 1B can be reduced.

The second arc-shaped portion 162 straddles the distance between the first end portion 161a and the second end portion 161b of the first arc-shaped portion 161. According to this configuration, since the filling grease 160 is arranged in the entire circumferential direction, the filling grease 160 is arranged in the entire circumferential direction in the bearing 1B as compared with the configuration in which the filling grease is not arranged in a part of the circumferential direction. Can be evenly arranged. Further, since the first end portion 161a and the second end portion 161b of the first arc-shaped portion 161 are continuously supported by the second arc-shaped portion 162, it is possible to prevent the filled grease 160 from collapsing due to disturbance or the like.

The seal member 50 is attached to an outer ring 20 which is a raceway ring with which the filling grease 160 comes into contact. According to this configuration, since the outer ring 20 and the seal member 50 are provided so as not to rotate relative to each other, it is possible to prevent the filling grease 160 in contact with both from being agitated. Therefore, the filled grease 160 can be kept in the shape immediately after application. Therefore, the torque of the bearing 1B can be reduced.

The second arc-shaped portion 162 is arranged on the side opposite to the outer ring 20 in the radial direction with respect to the first arc-shaped portion 161. According to this configuration, a space for arranging the first arc-shaped portion 161 is provided on the radial outer side of the second arc-shaped portion 162 as compared with the configuration in which the first arc-shaped portion and the second arc-shaped portion are arranged in the axial direction. The arcuate portion 161 can be arranged on the outer side in the axial direction. As a result, it is possible to prevent the filled grease 160 from coming into contact with the rolling elements 30 and the cage 40 more than necessary. Therefore, the torque of the bearing 1B can be reduced.

According to the method for manufacturing the bearing 1B of the present embodiment, the cycle time at each coating position can be shortened. Therefore, the manufacturing efficiency of the bearing 1B can be improved. Further, in the manufacturing method of applying grease in an arc shape while rotating the bearing, a mechanism for driving the nozzle in the radial direction with respect to the bearing becomes unnecessary, so that the structure of the grease application device can be simplified.

[Fourth Embodiment]
A fourth embodiment according to the present invention will be described with reference to FIG. The configuration other than that described below is the same as that of the first embodiment.

FIG. 8 is a cross-sectional view of the rolling bearing of the fourth embodiment.
In the fourth embodiment shown in FIG. 8, the bearing 1C includes other grease 65 in addition to the filling grease 60. The other grease 65 is arranged on the side opposite to the filling grease 60 in the axial direction with respect to the rolling element 30. That is, the other grease 65 is arranged on the same side as the main body 41 of the cage 40 in the axial direction with respect to the rolling element 30. The other grease 65 is arranged between the rolling element 30 and the sealing member 50. The other grease 65 is arranged in an annular space between the inner ring 10 and the outer ring 20. The other grease 65 is in contact with the contact target (outer ring 20 in this embodiment) of the filled grease 60 of the inner ring 10 and the outer ring 20. Like the filled grease 60, the other grease 65 is in contact with one of the inner ring 10 and the outer ring 20 and is separated from the other. The other grease 65 is separated from the rolling element 30 and the cage 40. The other grease 65 extends in a circumferential shape around the common axis O. The other grease 65 is in contact with a portion of the inner peripheral surface of the protruding portion 22 of the outer ring 20 that is axially outer of the outer ring rolling surface 23.

However, the composition of other greases is not limited to the above configuration. The other grease may be in contact with the inner ring 10 and separated from the outer ring 20. Further, the other grease may be in contact with at least one of the rolling element 30 and the cage 40. Further, the other grease does not have to extend in a circumferential shape. For example, the other grease may extend in a circumferential shape or may be arranged in a dot shape along the circumferential direction.

According to this embodiment, the total amount of grease arranged on the bearing 1C can be increased by the other grease 65. Therefore, it is possible to provide the bearing 1C having a long life.

[Fifth Embodiment]
A fifth embodiment according to the present invention will be described with reference to FIG. The configuration other than that described below is the same as that of the first embodiment.

FIG. 9 is a cross-sectional view of the rolling bearing of the fifth embodiment.
In the fifth embodiment shown in FIG. 9, the bearing 1D includes other grease 66 in addition to the filling grease 60. The other grease 66 is supported by the cage 40. The other grease 66 is arranged in the pocket between the pair of claws 42 on the side of the cage 40 opposite to the rolling element 30 with the claws 42 in between. In the illustrated example, the other grease 66 is in contact with the main body 41 of the cage 40, but may be in contact with the claw 42. The other grease 66 is separated from the rolling element 30 and the filling grease 60. The other grease 66 may be arranged in all the pockets of the cage 40, or may be arranged in only a part of the pockets.

According to this embodiment, the total amount of grease arranged on the bearing 1D can be increased by the other grease 66. Therefore, it is possible to provide a bearing 1D having a long life.

The present invention is not limited to the above-described embodiment described with reference to the drawings, and various modifications can be considered within the technical scope thereof.
For example, in the above embodiment, the inner ring 10 is provided as a rotating ring, and the outer ring 20 is provided as a fixed ring. Then, the filled greases 60, 60A, 160 are in contact with the outer ring 20 which is a fixed ring. However, the raceway ring with which the filling grease comes into contact does not have to be a fixed ring. That is, the inner ring may be provided as a fixed ring, the outer ring may be provided as a rotating ring, and the filled grease may be in contact with the inner ring which is the fixed ring. Further, the inner ring may be provided as a fixed ring, the outer ring may be provided as a rotating ring, and the filled grease may be in contact with the outer ring which is the rotating ring. In this case, the filled grease rotates together with the outer ring, but even if centrifugal force acts on the filled grease, the outer ring regulates the displacement of the grease to the outside in the radial direction, so the filled grease can be kept in the shape immediately after application. can. However, it is desirable that the filled grease is in contact with the raceway ring to which the seal member is attached among the inner ring and the outer ring.

Further, in the third embodiment, the volume ratio of the first arc-shaped portion 161 and the second arc-shaped portion 162 of the filling grease 160 is not particularly limited. For example, the cross-sectional areas of the cross-sectional areas of the first arc-shaped portion 161 and the second arc-shaped portion 162 may be equal to each other or different from each other.

Further, in the third embodiment, the filling grease 160 has two arcuate portions 161, 162, but by applying the grease in three or more times, it has three or more arcuate portions. May be good. However, when the grease is applied in a plurality of times, it is desirable that each of the arcuate portions is formed so that a space is provided between both end portions, similarly to the arcuate portions 161, 162 described above.

Further, in the above embodiment, the fan motor is exemplified as the rotating device, but the rotating device is not limited to this. For example, the present invention may be applied to at least one of a spindle motor and a swing arm of a hard disk drive as a rotating device.

In addition, it is possible to replace the components in the above-described embodiments with well-known components as appropriate without departing from the spirit of the present invention, and the above-described embodiments may be combined as appropriate. For example, the stringing portion 63 of the second embodiment may be connected to at least one of the first arc-shaped portion 161 and the second arc-shaped portion 162 of the second embodiment. For example, the other grease 65 of the fourth embodiment or the other grease 66 of the fifth embodiment may be arranged on the bearing 1A of the second embodiment or the bearing 1B of the third embodiment.

1,1A, 1B, 1C, 1D ... Rolling bearing 2 ... Rotating equipment 3 ... Shaft (rotating body) 4 ... Housing (support) 10 ... Inner ring 20 ... Outer ring 30 ... Rolling body 50 ... Seal member 60, 60A, 160 ... Filled grease (grease) 61 ... Arc-shaped part 61a ... First end of arc-shaped part 61b ... Second end of arc-shaped part 63 ... Threading part 65 ... Other grease 161 ... First arc-shaped part (arc-shaped part) 161a ... First end of the first arc (first end of the arc) 161b ... Second end of the first arc (second end of the arc) 162 ... Second arc (other arc) 162a ... First end of the second arc (first end of the other arc) 162b ... Second end of the second arc (second end of the other arc) O ... Common axis

Claims (11)

With the inner and outer rings arranged coaxially with each other,
A rolling element arranged between the inner ring and the outer ring,
Grease arranged between the inner ring and the outer ring,
With
The grease extends in an arc shape in the circumferential direction around the common axis at predetermined positions in the axial direction of the common axis of the inner ring and the outer ring and in the radial direction about the common axis, and the inner ring and the outer ring. Has a single arc in contact with one of the
The first end portion of the arc-shaped portion is arranged at intervals in the circumferential direction with respect to the second end portion of the arc-shaped portion.
Rolling bearings. One of the inner ring and the outer ring is provided as a fixed ring.
The rolling bearing according to claim 1. One of the inner ring and the outer ring is the outer ring.
The rolling bearing according to claim 1 or 2. The grease further comprises a stringing portion extending from one of the first end of the arc and the second end of the arc.
The stringing portion straddles the distance between the first end portion of the arc-shaped portion and the second end portion of the arc-shaped portion, and the first end portion of the arc-shaped portion and the second end portion of the arc-shaped portion. To be connected to
The rolling bearing according to any one of claims 1 to 3. A sealing member that covers between the inner ring and the outer ring from the outside in the axial direction is further provided.
The grease extends in an arc shape in the circumferential direction at a position different from the arc shape portion in the axial direction and the radial direction, and further extends a single other arc shape portion in contact with the seal member while being connected to the arc shape portion. Prepare,
The first end portion of the other arcuate portion is arranged at intervals in the circumferential direction with respect to the second end portion of the other arcuate portion.
The rolling bearing according to any one of claims 1 to 4. The other arc-shaped portion straddles the distance between the first end portion of the arc-shaped portion and the second end portion of the arc-shaped portion.
The rolling bearing according to claim 5. The sealing member is attached to one of the inner ring and the outer ring.
The rolling bearing according to claim 5 or 6. The other arc-shaped portion is arranged on the side opposite to the one of the inner ring and the outer ring in the radial direction with respect to the arc-shaped portion.
The rolling bearing according to any one of claims 5 to 7. Further provided with other grease arranged on the rolling element on the side opposite to the grease in the axial direction.
The rolling bearing according to any one of claims 1 to 8. Rotating bodies arranged rotatably and
A support that rotatably supports the rotating body and
The rolling bearing according to any one of claims 1 to 9, which is interposed between the rotating body and the support.
Rotating equipment equipped with. The method for manufacturing a rolling bearing according to any one of claims 5 to 8.
In the first coating step of forming the arcuate portion by discharging grease from the first nozzle at the first coating position,
A second coating step in which grease is discharged from a second nozzle different from the first nozzle at a second coating position different from the first coating position to form the other arcuate portion.
A method of manufacturing a rolling bearing.

Images