WO2014098212A1

WO2014098212A1 - Rolling bearing

Info

Publication number: WO2014098212A1
Application number: PCT/JP2013/084232
Authority: WO
Inventors: 山口　晃; 片岡　健一; 鈴木　佑
Original assignee: 日本精工株式会社
Priority date: 2012-12-21
Filing date: 2013-12-20
Publication date: 2014-06-26
Also published as: JP2014139474A; DE212013000259U1; CN104105893A

Abstract

The cage (20) of this rolling bearing is formed by joining multiple cage segments (21) in series in the circumferential direction and configures a substantially polygonal cylinder shape or a substantially polygonal frustum cylinder shape. The difference between the designed value for the circumferential dimension (H) of the multiple cage segments (21) and the actual length at normal temperature is 0.075% or less. The pillar sections (1) are provided with guides (6) for preventing the falling of the rolling element inward in the radial direction and for guiding the rolling element. Gaps, which allow displacement of the cage segments (21) in the diameter direction, are formed between the guides (6) and the rolling surfaces of conical rollers (7).

Description

Rolling bearing

The present invention relates to a rolling bearing.

Rolling bearings generally include an outer ring, an inner ring, and a plurality of rolling elements disposed between the outer ring and the inner ring, and the plurality of rolling elements are held by a cage. As a cage, an integrated cage formed of a single member is usually used. However, large-sized rolling bearings used in wind power generators, steel facilities, construction machinery, etc., require assembly and maintenance. For ease of use, a split cage may be used. Such a split type retainer forms a retainer having a cylindrical shape or a truncated cone shape as a whole by combining a plurality of retainer segments in series in the circumferential direction (for example, Patent Documents 1 and 2).

The conventional split-type cage will be described in more detail with reference to FIGS. As shown in FIG. 12, a plurality of cage segments 121 formed in an arc shape are combined in series in the circumferential direction to form a so-called divided cage 120 having a cylindrical or conical cylindrical shape as a whole. As shown in FIG. 13, each cage segment 121 is formed in an arc shape as a whole, and a pair of

rim portions

102, 102 provided at both axial ends are arc-shaped, and the rim portion 102. , 102 are connected to each other. A pocket 103 for holding a roller (not shown) in a freely rollable manner by a portion surrounded by the inner side surfaces of the

rim portions

102 and 102 and the circumferential side surfaces of the

column portions

101 and 101 adjacent in the circumferential direction. 103 is formed. Of the inner surfaces of the

pockets

103, 103, the circumferential side surfaces of the

column portions

101, 101 serve as guide surfaces for guiding the rolling surfaces of the respective rollers.

In this conventional split-type cage 120, the relationship between the total circumferential gap H ′ of adjacent cage segments 121 and the circumference L ′ of the cage pitch circle P ′ is H ′ ≦ 0.001L ′ at room temperature. By doing so, the breakage due to the collision between the cage segments 121 is prevented. Further, by providing a gap in which the cage segment 121 can be displaced in the radial direction between the inner surface of the pocket 103 of the cage segment 121 and the rolling surface of the roller (not shown), the cage segment 121 when the temperature rises. The pocket 103 is prevented from being distorted due to mutual interference and the split cage 120 is prevented from being damaged.

Japanese Unexamined Patent Publication No. 2009-97525 European Patent Application No. 1408248

However, the processing of the mold for injection molding the arc-shaped cage segment 121 as described above is very expensive.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a rolling bearing provided with a split cage that can be manufactured at low cost.

The above object of the present invention can be achieved by the following constitution.
(1) an outer ring having an outer ring raceway surface formed on the inner circumferential surface;
An inner ring having an inner ring raceway surface formed on the outer circumferential surface;
A plurality of rolling elements arranged circumferentially in a freely rollable manner between the outer ring raceway surface and the inner ring raceway surface;
It is formed by combining a plurality of cage segments each having a pair of side plates arranged parallel to the axial direction and a plurality of pillars connecting the pair of side plate portions in the axial direction in series in the circumferential direction, A rolling bearing comprising: a retainer that holds the rolling element in a pocket formed by the pair of side plate portions and the pillar portion facing in the circumferential direction;
The radially outer end surface and the radially inner end surface of the side plate portion are planes parallel to each other,
The cage formed by combining a plurality of cage segments in series in the circumferential direction constitutes a substantially polygonal cylinder shape or a substantially polygonal truncated cone shape,
The difference between the design value of the circumferential dimension of the cage segment and the actual length of the circumferential dimension of the cage segment at room temperature is 0.075% or less,
The column portion is provided with a guide portion that guides the rolling element by preventing the rolling element from dropping out inward in the radial direction,
A rolling bearing, wherein a gap is formed between the guide portion and the rolling surface of the rolling element so that the cage segment can be displaced in the radial direction.
(2) The column portion is provided with a protrusion that prevents the rolling element from falling off radially outwardly,
The rolling bearing according to (1), wherein the protrusion and the guide have a shape along the rolling element disposed on the inner ring raceway surface.
(3) The cage segment has a protruding portion that protrudes in the circumferential direction from both circumferential end surfaces of the cage segment continuously from the axially outer end surface of each side plate portion,
The axially inner end surface of the protruding portion is located axially inner than the axially inner end surface of the side plate portion,
The rolling bearing according to (1) or (2), wherein when the plurality of cage segments are combined in series in the circumferential direction, the neighboring cage segments are in contact with each other at the protruding portion.
(4) The cage segment is formed of any synthetic resin of aromatic nylon, polyetheretherketone, and polyphenylsulfide, according to any one of (1) to (3), Rolling bearing.

According to the present invention, it is possible to provide a rolling bearing provided with a split cage that can be manufactured at low cost.

It is a schematic diagram for demonstrating the split type holder | retainer concerning 1st Embodiment of this invention. It is a perspective view of the holder | retainer segment which comprises the split-type holder | retainer of FIG. FIG. 3 is a circumferential sectional view of the cage segment of FIG. 2. FIG. 3 is a side view of the cage segment of FIG. 2. FIG. 3 is a plan view of the cage segment of FIG. 2. FIG. 3 is a circumferential sectional view of the cage segment of FIG. 2 and is a view for explaining a radial gap between a guide portion and a tapered roller. FIG. 3 is a cross-sectional view in the circumferential direction of the cage segment of FIG. 2 for explaining the shape of a guide portion. It is a perspective view of the holder | retainer segment which comprises the split-type holder | retainer concerning 2nd Embodiment of this invention. FIG. 9 is a side view of the cage segment of FIG. 8. FIG. 9 is a plan view of the cage segment of FIG. 8. It is a principal part enlarged view of FIG. It is a schematic diagram which shows an example of the conventional split type holder. It is a perspective view of the retainer segment of the conventional split type retainer.

Hereinafter, the rolling bearing according to each embodiment of the present invention will be described with reference to FIGS.

(First embodiment)
A rolling bearing according to a first embodiment of the present invention will be described with reference to FIGS. As shown in FIG. 1, the cage 20 used in the rolling bearing of this embodiment includes a plurality of cage segments 21 formed of a synthetic resin such as aromatic nylon, polyether ether ketone, polyphenylene sulfide, in the circumferential direction. This is a so-called split type cage formed by combining in series. In the present embodiment, the cage 20 is formed by combining 18 cage segments 21 in series in the circumferential direction. Hereinafter, the number of cage segments necessary to form one cage is referred to as the number of cage divisions (18 in this example). The cage segments 21 are not mechanically coupled to each other, but are arranged in series in the circumferential direction between the outer ring and the inner ring to form the cage 20.

As shown in FIGS. 2 to 5, each cage segment 21 includes a pair of

side plate portions

2 and 2 arranged parallel to the axial direction, and a plurality of the

side plate portions

2 and 2 that connect the pair of

side plate portions

2 and 2 in the axial direction. Column part 1. A pocket 3 for holding the tapered roller 7 (see FIG. 3) is formed by the axially

inner end surfaces

2c and 2c of the

side plate portions

2 and 2 and the

side surfaces

1c and 1c of the

column portions

1 and 1 facing in the circumferential direction. It is formed. In the present embodiment, a pair of

side plate portions

2 and 2 are connected by four column portions 1 arranged at a predetermined interval in the circumferential direction, whereby three pockets 3 are formed. The tapered rollers 7 held one by one in each pocket 3 of the cage segment 21 include an outer ring raceway surface 70 formed on the inner peripheral surface of the outer ring and an inner ring raceway surface 80 formed on the outer peripheral surface of the inner ring. It is arranged so that it can roll between.

As shown in FIG. 2, each pillar portion 1 is formed with an oil groove 4 that opens radially inward in the axially intermediate portion and penetrates in the circumferential direction, and the rolling surface of the tapered roller 7 and the inner ring raceway. Lubrication between the surface 80 is possible. As shown in FIGS. 2 and 3, a pair of

protrusions

5, 5 provided side by side in the axial direction are formed in the vicinity of the radially outer side of the side surface 1 c of the column part 1. Is prevented from falling off radially outward. Further, in the vicinity of the inner side in the radial direction of the side surface 1c of the column part 1, a pair of

guide portions

6, 6 provided at both ends in the axial direction are formed, and the tapered roller 7 is prevented from falling off inward in the radial direction. ing. At this time, the relation between the width A between the projecting

portions

5 and 5 facing in the circumferential direction in the

column portions

1 and 1 facing in the circumferential direction and the diameter d of the tapered roller 7 satisfies A <d. In addition, the relationship between the width B between the

guide portions

6 and 6 facing in the circumferential direction in the

column portions

1 and 1 facing in the circumferential direction and the diameter d of the tapered roller 7 satisfies B <d. Thereby, the tapered roller 7 is held in the pocket 3 without dropping off.

As shown in FIG. 4, each side plate portion 2 is configured such that the radially outer end surface 2 a and the radially inner end surface 2 b are parallel to each other. Thereby, the metal mold | work for forming the side-plate part 2 of the holder | retainer segment 21 becomes easy, and it becomes possible to manufacture more cheaply.

Moreover, as shown in FIG. 4, the circumferential direction end surfaces 1a and 1a of the cage segment 21 are formed so as to form a predetermined inclination angle C from the radially outer side to the inner side according to the number of cage divisions. Yes. As shown in FIG. 5, the circumferential end surfaces 1 a and 1 a of the cage segment 21 have a predetermined inclination angle from one side in the axial direction toward the other side depending on the number of cage divisions and the shape of the cage 20. D is formed. In such circumferential end faces 1a and 1a, a plurality of cage segments 21 are butted in the circumferential direction and combined in series, whereby a generally polygonal truncated cone-shaped cage 20 can be configured. 4 and 5, reference numeral 2 d denotes an axially outer end surface of the pair of

side plate portions

2 and 2.

In addition, as shown in FIG. 1, the design value of the circumferential dimension H for assembling the plurality of cage segments 21 without gaps in the circumferential direction is the inner ring dimension and the outer ring dimension when the cage segments 21 are the same. It is geometrically determined by the roller size of the tapered roller 7, the number of rollers, the gap between the pocket 3 and the tapered roller 7, the thickness of the cage 20, and the number of cage segments 21. In addition, as the circumferential dimension H of the target cage segment 21, the radially outer end face 2a of the side plate portion 2 may be used, or the radially inner end face 2b may be used. The circumferential dimension H of the plurality of cage segments 21 is specified such that the actual length at normal temperature (about 20 ° C.) is 0.075% or less in absolute value with respect to the design value. That is, by making the difference between the design value of the circumferential dimension H of the plurality of cage segments 21 and the actual length at normal temperature (about 20 ° C.) 0.075% or less in absolute value, Can be combined with almost no gap.

Further, as shown in FIG. 6, the pocket 3 is formed such that a gap e between which the cage segment 21 can be displaced in the radial direction is provided between the guide portion 6 and the rolling surface of the tapered roller 7. Yes. As a result, even when the cage segment 21 expands in the circumferential direction due to temperature rise, water absorption, or the like, the cage segment 21 can be displaced in the outer diameter direction within the gap e, so The interference between the

vessel segments

21 and 21 can be reduced. Therefore, the distortion of the pocket 3 and the breakage of the cage segment 21 can be prevented.

Further, the protrusion 5 and the guide 6 of the column part 1 are formed in a shape along the rolling surface of the tapered roller 7. In other words, among the three pockets 3 formed in the cage segment 21, one central pocket 3 a disposed in the center and two end pockets 3 b disposed on both sides in the circumferential direction of the central pocket 3 a are projected. The shapes of the part 5 and the guide part 6 are changed.

Specifically, as shown in FIGS. 6 and 7, the central pocket 3 a is provided with

projections

5 a and 5 a that are formed short inward in the radial direction so as not to disturb the rolling of the tapered roller 7. ing. Further, the guide surfaces 6 a and 6 a of the guide portion 6 in the central pocket 3 a are formed in a shape along the conical trapezoid 8 by a radius of curvature along the conical trapezoid 8 larger than the tapered roller 7.

On the other hand, as shown in FIGS. 6 and 7, in the end pocket 3 b, the central protrusion 5 b formed long toward the radially inner side so as to prevent the tapered roller 7 from falling off, and the tapered roller 7 is provided with a projection 5b 'on the end side that is formed to be short inward in the radial direction so as not to interfere with the rolling of 7. Further, the guide surface 6b on the center side of the guide portion 6 and the guide surface 6b 'on the end portion side in the end pocket 3b have a radius of curvature along the conical trapezoid 8 and are center pockets around the rotation axis of the rolling bearing. It is formed in a shape along a truncated cone 8 rotated by a predetermined width from 3a. Thus, the

projections

5a, 5b, 5b ′ and the guide surfaces 6a, 6b, 6b ′ are along the rolling surface of the tapered roller 7 arranged between the outer ring raceway surface 70 and the inner ring raceway surface 80. The tapered roller 7 can be reliably guided by being formed into a shape.

Thus, according to the cage segment 21 of the rolling bearing of the first embodiment, the radial outer end surface 2a and the radial inner end surface 2b of the cage segment 21 are planes parallel to each other. The side plate portion 2 can be easily processed with a mold, and can be manufactured at a lower cost.

Further, since the cage segment 21 is formed of a synthetic resin such as aromatic nylon, polyetheretherketone, or polyphenylene sulfide, the cage segment 21 can be reduced in weight, and can be self-lubricated and have low friction. Thus, the cage segment 21 excellent in corrosion resistance, quietness and the like can be obtained. Moreover, according to these synthetic resins, since the cage segment 21 can be manufactured by injection molding, it is possible to manufacture at a lower cost by mass production.

Further, the projections 5 and the guides 6 formed on the pillars 1 in each pocket 3 are formed along the rolling surfaces of the tapered rollers 7 disposed between the outer ring raceway surface 70 and the inner ring raceway surface 80. By doing so, the tapered roller 7 can be reliably guided.

(Second Embodiment)
Hereinafter, a rolling bearing according to a second embodiment of the present invention will be described with reference to FIGS. The cage segment 31 constituting the split cage of the rolling bearing according to the second embodiment is the first embodiment except that the cage segment 31 includes a protruding portion 9 projecting in the circumferential direction from the circumferential end surface 1d of the cage segment 31. It is the same as the cage segment 21 in the form. Accordingly, corresponding elements are denoted by common reference numerals and numbers, and description of common structures is omitted.

In the cage segment 31 shown in FIG. 8, the protrusions that protrude from the circumferential end surfaces 1 d and 1 d of the cage segment 31 outward in the circumferential direction are continuous from the axially outer end surfaces 2 d of the pair of

side plate portions

2 and 2. 9, 9 are formed. When the plurality of cage segments 31 are combined in series in the circumferential direction, the projecting portion circumferential end faces 9a and 9a facing each other in the circumferential direction in the neighboring

cage segments

31 and 31 are abutted and contacted. Thereby, since the collision load of the

adjacent cage segments

31 and 31 can be received by the protruding portion 9, when the

adjacent cage segments

31 and 31 collide with each other, the corner portion of the pocket 3 is deformed by the deformation of the column portion 1. The stress that may be generated in the protrusion 9 can be relaxed.

As shown in FIG. 9, the projecting portion circumferential end faces 9a, 9a of each cage segment 31 are formed so as to form a predetermined inclination angle F from the radially outer side to the inner side according to the number of cage divisions. ing. Moreover, as shown in FIG. 10, the protrusion part circumferential direction end surfaces 9a and 9a of the cage segment 31 have a predetermined inclination from the one side in the axial direction toward the other side according to the number of cage divisions and the shape of the cage. It is formed so as to form an angle G. In such projecting portion circumferential end faces 9a and 9a, the

cage segments

31 and 31 are butted in the circumferential direction and combined in series, whereby a substantially polygonal truncated cone shaped cage 20 can be configured.

The protruding portion 9 has a protruding portion axially inner end surface 9b continuous from the protruding portion circumferential end surface 9a to the circumferential end surface 1d of the cage segment 31. The protruding portion axially inner end surface 9b is formed so as to be positioned on the axially inner side of the axially inner end surface 2c of the side plate portion 2, whereby the tapered roller 7 in the pocket 3 collides with the column portion 1. In some cases, the stress that may occur at the corners of the pocket 3 can be relieved by the protrusions 9. In addition, in this embodiment, although the protrusion part axial direction inner side end surface 9b is diagonally formed with respect to the circumferential direction end surface 1d of the holder | retainer segment 31 by chamfering, it does not need to be chamfered.

It should be noted that the present invention is not limited to the above-described embodiment, and can be changed or improved as appropriate. In each of the embodiments described above, the tapered roller bearing having the split type cage has been described. However, the present invention can also be applied to the case of assembling the cylindrical roller bearing having the split type cage. 1a and the protrusion part circumferential direction end surface 9a will incline only toward radial direction. In addition, the number of

cage segments

21 and 31 and the number of pockets 3 formed in each

cage segment

21 and 31 can be appropriately determined according to the dimensions and application of the rolling bearing.

This application is based on a Japanese patent application filed on December 21, 2012 (Japanese Patent Application No. 2012-280248 and a Japanese patent application filed on December 12, 2013 (Japanese Patent Application No. 2013-257136). Is incorporated herein by reference.

DESCRIPTION OF SYMBOLS 1 Column part 2 Side plate part 2a Radial outer side end surface 2b Radial inner side end surface 3 Pocket 5 Protrusion part 6 Guide part 7 Tapered roller 9

Protrusion part

20, 120

Cage

21, 121 Cage segment 70 Outer raceway surface 80 Inner raceway surface

Claims

An outer ring having an outer ring raceway surface formed on the inner circumferential surface;
An inner ring having an inner ring raceway surface formed on the outer circumferential surface;
A plurality of rolling elements arranged circumferentially in a freely rollable manner between the outer ring raceway surface and the inner ring raceway surface;
It is formed by combining a plurality of cage segments each having a pair of side plates arranged parallel to the axial direction and a plurality of pillars connecting the pair of side plate portions in the axial direction in series in the circumferential direction, A rolling bearing comprising: a retainer that holds the rolling element in a pocket formed by the pair of side plate portions and the pillar portion facing in the circumferential direction;
The radially outer end surface and the radially inner end surface of the side plate portion are planes parallel to each other,
The cage formed by combining a plurality of cage segments in series in the circumferential direction constitutes a substantially polygonal cylinder shape or a substantially polygonal truncated cone shape,
The difference between the design value of the circumferential dimension of the cage segment and the actual length of the circumferential dimension of the cage segment at room temperature is 0.075% or less,
The column portion is provided with a guide portion that guides the rolling element by preventing the rolling element from dropping out inward in the radial direction,
A rolling bearing, wherein a gap is formed between the guide portion and the rolling surface of the rolling element so that the cage segment can be displaced in the radial direction.
The column portion is provided with a protrusion portion that prevents the rolling element from falling off in the radial direction.
The rolling bearing according to claim 1, wherein the protrusion and the guide have a shape along the rolling elements arranged on the inner ring raceway surface.
The cage segment has a protruding portion that protrudes in the circumferential direction from both circumferential end surfaces of the cage segment continuously from the axially outer end surface of each side plate portion,
The axially inner end surface of the protruding portion is located axially inner than the axially inner end surface of the side plate portion,
The rolling bearing according to claim 1, wherein when the plurality of cage segments are combined in series in the circumferential direction, adjacent cage segments are in contact with each other at the protrusion.
The rolling bearing according to any one of claims 1 to 3, wherein the cage segment is made of a synthetic resin of any one of aromatic nylon, polyether ether ketone, and polyphenyl sulfide.