JP2024074111A - Tapered roller bearing - Google Patents

Abstract

To provide a tapered roller bearing capable of increasing strength of a retainer while suppressing a usage amount of a retainer material.SOLUTION: A retainer segment 20 of a tapered roller bearing includes a plurality of pillars 23 extending in an axial direction, and a pair of arcuate portions 21, 22 extending in a circumferential direction and connecting the plurality of pillars 23 respectively. A pocket 16 for retaining a tapered roller between the pillars 23, 23 adjacent with each other is formed by the plurality of pillars 23 and the pair of arcuate portions 21, 22. A surface sf constituting the pocket 16 of the arcuate portions 21, 22 or the pillar 23 is inclined with respect to a radial direction of the pocket 16 of the retainer segment 20. A round shape which becomes larger as going to one side or the other side in the radial direction is formed in a part or the whole of a corner Cr of the pocket 16.SELECTED DRAWING: Figure 2

Description

The present invention relates to tapered roller bearings, for example, large tapered roller bearings for use in the main shafts of wind power generation equipment or industrial machinery, particularly those with an outer diameter exceeding 1 m.

In rolling bearings, the cage that holds the rolling elements is usually composed of a single annular part. Metallic pressed cages, machined cages, welded cages, plastic cages, etc. are used as the cage depending on the application and characteristics. The rolling bearings that support the main shaft of a wind power generation device are large because they bear heavy loads, making the production and assembly of the components difficult. In order to facilitate the production and assembly of the cage for such large rolling bearings, plastic cage segments that make the cage separable have been proposed (Patent Documents 1 and 2).

European Patent No. 1408248 JP 2009-52476 A

Plastic cage segments are manufactured by injection molding, and a gradient must be provided on the cage segment to allow the segment to be removed from the mold during injection molding. This gradient requires the arc or column sections of the cage segment to be made thinner, which reduces the cage strength. In addition, plastic materials generally have lower tensile strength and tensile modulus than carbon steel. Meanwhile, cages for large roller bearings with an outer diameter of over 1m must be strong enough to withstand large loads and long-term operation.
In addition, the cage segments are made of expensive resin materials such as PEEK resin, etc. For these reasons, there is a demand for a cage segment structure that can reduce the amount of material used while increasing its strength.

The object of the present invention is to provide a tapered roller bearing that can increase the strength of the cage while reducing the amount of cage material used.

The tapered roller bearing of the present invention comprises an inner and outer ring, a plurality of tapered rollers interposed between the inner and outer rings, and a cage for holding the tapered rollers, the cage including a plurality of cage segments arranged in an annular shape,
the retainer segment includes a plurality of column portions extending in an axial direction and a pair of arc-shaped portions extending in a circumferential direction and connecting the plurality of column portions, respectively; and a pocket for holding the tapered rollers is formed between adjacent column portions of the plurality of column portions and the pair of arc-shaped portions,
The surfaces of the arc-shaped portions or columnar portions that constitute the pocket are inclined relative to the radial direction of the pocket of the retainer segment, and some or all of the corners of the pocket have an R-shape that becomes larger toward one side or the other in the radial direction.
The "corner" refers to a portion of the pocket where the column portion and the arc-shaped portion are connected in an arc shape.

With this configuration, some or all of the corners of the pocket have an R shape that becomes larger in one radial direction or the other, which reduces stress concentration compared to typical retainer segments. The corners of the pocket are areas where large stress occurs when the bearing is in operation, and by reducing the stress concentration at the corners, the strength of the retainer segment is improved compared to typical retainer segments. This reduces the risk of abnormalities during bearing operation. In addition, because the strength of the retainer segment is improved, the retainer segment can be made thinner. This makes it possible to reduce the amount of retainer material compared to typical retainer segments, and thus reduce manufacturing costs.

The cage segments may be made of resin. In this case, each cage segment can be molded using a mold or the like, making it easy to accommodate larger tapered roller bearings and mass production.

The cage segments may be made of a resin containing carbon fiber or glass fiber. Because carbon fiber or glass fiber is fibrous, it can efficiently reduce the thermal linear expansion coefficient, i.e., the thermal expansion coefficient. This can prevent the gap between the segments from becoming zero during expansion. This can prevent cage malfunctions in advance.

The retainer segments may be formed by injection molding. In this case, in order to form the retainer segments by injection molding, it is necessary to provide a gradient in the direction in which the mold is removed. When the mold is removed in the radial direction of the retainer segment, the surfaces of the arc-shaped or columnar portions of the retainer segment that form the pockets are provided with a gradient so that they widen in the direction in which the mold is removed. This gradient can be used to easily provide the R shape of the corners.

The tapered roller bearing may be a large bearing with an outer diameter of 1 m or more, which is used in wind power generation equipment. In this case, the tapered roller bearing, which has improved strength of the cage segments, can be applied to the large bearing used in the wind power generation equipment, and the maintenance costs of the tapered roller bearing can be reduced.

Guide claws that enable the tapered rollers to be inserted into pockets from the inner diameter side of the cage segment may be provided on the outer diameter side of adjacent column sections, and connecting members that connect the multiple cage segments may be detachably provided on engagement sections provided on each cage segment. In this case, when the inner ring assembly, in which the inner ring, tapered rollers and cage are integrated, is assembled into the outer ring, even if the inner ring assembly is turned over, the annularly arranged cage segments are connected by the connecting members. This allows the tapered roller bearing to be easily assembled without the cage segments coming apart.

In the tapered roller bearing of the present invention, the surfaces of the arcuate or columnar portions of the retainer segments that form the pockets are inclined relative to the radial direction of the pockets of the retainer segments, and some or all of the corners of the pockets have an R shape that becomes larger in one direction or the other in the radial direction. This makes it possible to increase the strength of the retainer while reducing the amount of retainer material used.

1 is a vertical sectional view of a tapered roller bearing according to a first embodiment of the present invention. FIG. 2 is a perspective view of a retainer segment of the tapered roller bearing. FIG. 2 is a partially enlarged perspective view of the cage segment. FIG. 4 is a cross-sectional view of the cage segment. FIG. 11 is a perspective view of a retainer segment of a tapered roller bearing according to a second embodiment of the present invention. FIG. 4 is a cross-sectional view of the cage segment. FIG. 11 is a vertical sectional view of a tapered roller bearing according to a third embodiment of the present invention. FIG. 2 is a perspective view of a retainer segment used in the tapered roller bearing. 4 is a cross-sectional view showing a state in which tapered rollers are inserted into the cage segment. FIG. FIG. 2 is a perspective view of the tapered roller bearing with the outer ring removed. FIG. 2 is a front view of the tapered roller bearing with the outer ring removed. 4 is a perspective view showing an assembly procedure of the tapered roller bearing. FIG. 13 is a perspective view showing the assembly procedure of FIG. 12 from a different angle. FIG. 4 is a schematic diagram showing the relationship between the tapered rollers and the large rib portion of the inner ring when the tapered rollers are arranged on the inner ring with the large end face of the inner ring facing down. FIG. 4 is a perspective view showing the tapered roller bearing in the middle of assembly. FIG. 4 is a perspective view showing the tapered roller bearing in the middle of assembly. FIG. 17 is a vertical sectional view of the tapered roller bearing in FIG. 16 during assembly. 17 is a vertical sectional view of the tapered roller bearing in the state shown in FIG. 16 with the annular jig removed. 4 is a vertical cross-sectional view showing a state in which the inner ring assembly is turned over and assembled into the outer ring. FIG. FIG. 4 is a vertical cross-sectional view showing the state in which the inner ring assembly is assembled into the outer ring. FIG. 4 is a schematic diagram showing a rotating state of a tapered roller arranged on an inner ring raceway surface. 4 is a schematic diagram showing the relationship between the height of a small rib portion of an inner ring and a tapered roller when the tapered roller arranged on an inner ring raceway surface is rotated. FIG. 1 is a cutaway perspective view of a wind turbine generator using a tapered roller bearing according to any one of the embodiments of the present invention. FIG.

[First embodiment]
A tapered roller bearing according to an embodiment of the present invention will be described with reference to Figures 1 to 4. This tapered roller bearing is applied, for example, to a main shaft of a wind power generating device or to a large tapered roller bearing for industrial machinery, particularly having an outer diameter exceeding 1 m.

<Outline of tapered roller bearing structure>
1, tapered roller bearing 1 comprises inner and outer rings 11, 12, a plurality of tapered rollers 15 interposed between these inner and outer rings 11, 12, and a cage 17 that holds these tapered rollers 15. A tapered raceway surface 13 is provided on the outer peripheral surface of the inner ring 11, and a tapered raceway surface (outer ring raceway surface) 14 is provided on the inner peripheral surface of the outer ring 12.

The tapered rollers 15 are arranged between the raceway surfaces 13, 14 so as to be able to roll freely, and a tapered rolling surface is formed on the outer circumferential surface of each tapered roller 15. The cage 17 holds the tapered rollers 15 at regular intervals in the circumferential direction. A small flange portion 18 is provided on the outer circumferential surface of the inner ring 11 adjacent to the small diameter side portion of the raceway surface 13, and a large flange portion 19 is provided on the outer circumferential surface of the inner ring 11 adjacent to the large diameter side portion of the raceway surface 13. The inner and outer rings 11, 12 and the tapered rollers 15 are made of, for example, bearing steel or stainless steel.

<Cage>
The cage 17 is an outer ring guided cage including a plurality of cage segments 20 arranged in an annular shape. Each cage segment 20 in FIG. 2 may be simply referred to as a segment 20. Each cage segment 20 is, for example, made of synthetic resin, has the same shape, and is injection molded using the same mold. The resin is preferably PEEK. The thermal linear expansion coefficient of PEEK itself is about 4.7×10 ⁻⁵ /° C., which is lower than other resin materials, so that it is easy to reduce the thermal linear expansion coefficient by including a filler. The filler preferably includes carbon fiber or glass fiber. These fillers including carbon fiber or glass fiber are fibrous, so that they can efficiently reduce the thermal linear expansion coefficient, i.e., the thermal expansion coefficient.

Each cage segment 20 has pockets 16 that hold a fixed number (five in this example) of tapered rollers 15 (Figure 1). Each cage segment 20 has a number of column sections 23 extending in the axial direction, and a pair of arc-shaped sections 21, 22 that extend in the circumferential direction and connect the column sections 23. The pockets 16 that hold the tapered rollers 15 (Figure 1) are formed between the adjacent column sections 23 by the column sections 23 and the pair of arc-shaped sections 21, 22.

The pair of arc-shaped portions 21, 22 each have an arc shape, and one arc-shaped portion 21 disposed on the small end face side of the tapered roller 15 is a small diameter side arc-shaped portion located on the smaller diameter side than the other arc-shaped portion 22. The other arc-shaped portion 22 is a large diameter side arc-shaped portion located on the larger diameter side than the one arc-shaped portion 21.
Guide claws 24 are provided on the outer diameter side of adjacent column portions 23, which enable tapered rollers 15 (FIG. 1) to be inserted into pockets 16 from the inner diameter side of the cage segment 20. The guide claws 24 come into contact with the tapered rollers 15 (FIG. 1) housed in the pockets 16 on the outer diameter side. The guide claws 24 in FIG. 4 prevent the tapered rollers 15 inserted in the pockets 16 from slipping out to the outer diameter side OS. The guide surface of each guide claw 24 has an arc-shaped cross section and is shaped to approximately fit the rolling surface of the tapered rollers 15.

<Means for stabilizing the cage attitude>
As shown in Fig. 2, guide projections 29 are provided at both axial ends of the cage segment 20 as cage attitude stabilizing means for stabilizing the attitude of the cage 17. The guide projections 29, 29 at both axial ends are provided at both axial ends of the outer circumferential surface of the column portion 23. In this example, the guide projections 29, 29 are provided on the column portions 23, 23 at both circumferential ends and on the column portions 23, 23 adjacent to these column portions 23 in the circumferential direction. Each guide projection 29 has a guide surface 29a that is guided by the outer ring raceway surface 14 (Fig. 1). Note that in the cage segment 20, the guide projections 29, 29 may be provided on any column portion 23 including the column portions 23, 23 at both circumferential ends.

<Methods for reducing stress concentration>
3 is an enlarged perspective view of a portion III in FIG. 2. As shown in FIG. 2 and FIG. 3, the surfaces sf of the arc-shaped portions 21, 22 and the column portion 23 that constitute the pocket 16 are inclined with respect to the radial direction A1 of the pocket 16 of the cage segment 20. In other words, the surfaces sf of the arc-shaped portions 21, 22 and the column portion 23 that constitute the pocket 16 have a gradient α with respect to a straight line Cp perpendicular to the imaginary plane that constitutes the pocket 16. As shown in FIG. 4, in the structure of this embodiment in which all the guide claws 24 for holding the tapered rollers 15 are extended to the outer diameter side OS, the gradient α is provided so that the interval between the column portions 23, 23 widens toward the inner diameter side IS in all the pockets 16. Also, as shown in FIG. 2, the gradient β is provided so that the interval between the pair of arc-shaped portions 21, 22 widens toward the inner diameter side in all the pockets 16.

As shown in FIG. 3, a part of the corner Cr of the pocket 16 has an R shape that becomes larger toward the inner diameter side (one side in the radial direction) IS. The corner Cr in FIG. 3 has an R shape over the entire radial direction. However, the part Ca of the corner Cr that has an R shape that becomes larger toward the inner diameter side IS is a part that extends from the radial middle of the pocket 16 to the inner diameter side edge. This part Ca that has an R shape that becomes larger toward the inner diameter side IS is a stress concentration reduction means that reduces stress concentration in the corner Cr. Note that the entire corner Cr of the pocket 16, that is, the entire radial direction from the outer diameter side edge to the inner diameter side edge of the pocket 16, may have an R shape that becomes larger toward the inner diameter side IS. The part that has the R shape is called the "corner R".

The corner R of the pocket of a typical roller bearing cage is smaller than the corner R of the roller to avoid interference with the roller. However, if there is an inclination on the surface of the cage's column or arc-shaped portion that constitutes the pocket, the gap between the roller and the pocket increases as the distance between the column portions or the distance between the pair of arc-shaped portions increases, and a corner R equal to or larger than the corner R of the roller can be provided at the corner of the cage pocket.

Plastic cages are generally formed by injection molding, and for this purpose it is necessary to provide a gradient in the direction in which the die is removed. When removing the die in the radial direction of the cage segment, the surfaces of the arcuate or columnar portions of the cage segment that form the pockets are provided with a gradient so that they expand in the direction A2 (Figure 4) in which the die is removed. This gradient can be used to easily provide the R shape of the corner portion Cr.

<About connecting parts, etc.>
As shown in Fig. 1, in this embodiment, connecting members 25, 33 that connect a plurality of cage segments 20 are detachably provided on each cage segment 20. As shown in Fig. 2, protrusions 26 are provided on both ends of the large diameter side surface of the large diameter side arcuate portion 22 of the segment 20 so as to protrude in the axial direction. The protrusions 26 have engagement portions 27 that engage with the connecting members 25 of Fig. 1. The connecting members 25, which are arranged on the large diameter side of each of the annularly arranged segments 20, are detachably provided on the engagement portions 27.
A small diameter side engaging portion (engaging portion) 32 is provided on the small diameter side surface of the small diameter side arcuate portion 21, and a connecting member 33 that is wound around the small diameter side of each annularly arranged segment 20 is passed through the small diameter side engaging portion 32. Furthermore, the ends of this connecting member 33 are detachably fastened to each other by a fastening member (not shown).

<Action and effect>
According to the tapered roller bearing 1 described above, as shown in FIG. 3, part or all of the corners Cr of the pocket 16 have an R shape that becomes larger toward the inner diameter side IS, so that stress concentration is reduced compared to a typical cage segment. The corners Cr of the pocket 16 are areas where large stress occurs when the bearing is in operation, and by reducing the stress concentration in the corners Cr, the strength of the cage segment 20 is improved compared to a typical cage segment. This reduces the risk of abnormalities during operation of the bearing. In addition, because the strength of the cage segment 20 is improved, the cage segment 20 can be made thinner. This makes it possible to reduce the cage material and manufacturing costs compared to a typical cage segment.

Since the retainer segments 20 are made of resin, each retainer segment 20 can be molded using a mold or the like, and can easily accommodate larger tapered roller bearings and mass production.
The cage segments 20 are made of resin containing carbon fiber or glass fiber. Because carbon fiber or glass fiber is fibrous, it is possible to efficiently reduce the linear expansion coefficient due to heat, i.e., the thermal expansion coefficient. Therefore, it is possible to prevent the gap between the segments from becoming zero during expansion. This makes it possible to prevent problems with the cage 17 in FIG. 1 from occurring.

As shown in FIG. 4, guide claws 24 that allow the tapered rollers 15 to be inserted into the pockets 16 from the inner diameter side IS of the cage segment 20 are provided on the outer diameter side of adjacent column sections 23, and as shown in FIG. 1, connecting members 25 that connect multiple cage segments 20 are detachably provided on engagement sections 27 provided on each cage segment 20. In this case, when the inner ring assembly in which the inner ring 11, tapered rollers 15 and cage 17 are integrated is assembled into the outer ring 12, even if the inner ring assembly is turned over, the annularly arranged cage segments 20 are connected by the connecting members 25. This allows the tapered roller bearing 1 to be easily assembled without the cage segments 20 coming apart.

<Other embodiments>
In the following description, parts corresponding to matters previously described in each embodiment are given the same reference numerals, and duplicated description is omitted. When only a part of the configuration is described, the other parts of the configuration are the same as the previously described embodiment unless otherwise specified. The same configuration has the same effect. It is possible to combine not only the parts specifically described in each embodiment, but also partially combine the embodiments, provided that there is no particular problem with the combination.

[Second embodiment: Figs. 5 to 6]
As shown in Fig. 5, the cage segment 20 may be provided with guide claws 24 on the inner diameter side and the outer diameter side of the column portion 23. Specifically, as shown in Fig. 6, among the multiple column portions 23, the column portions 23a, 23a at both circumferential ends and the column portions 23b, 23b adjacent to the column portions 23a, 23a are provided with guide claws 24a, 24a that enable the tapered roller 15 to be inserted from the outer diameter side OS of the cage segment 20 into the pocket 16. The column portions 23c, 23c that form the pocket 16 located in the middle in the circumferential direction are also provided with guide claws 24a, 24a that enable the tapered roller 15 to be inserted from the outer diameter side OS of the cage segment 20 into the pocket 16. The guide claws 24a come into contact with the tapered roller 15 accommodated in the pocket 16 on the inner diameter side IS. The guide claws 24a prevent the tapered roller 15 inserted in the pocket 16 from slipping out to the inner diameter side IS.

Of the multiple column sections 23, column sections 23b, 23b adjacent to column sections 23a, 23a at both circumferential ends and column sections 23c, 23c forming a pocket 16 located in the middle in the circumferential direction are provided with guide claws 24b, 24b on the outer diameter side OS, which allow tapered rollers 15 to be inserted into pocket 16 from the inner diameter side IS of the cage segment 20. The guide claws 24b come into contact with the tapered rollers 15 housed in the pocket 16 on the outer diameter side OS. These guide claws 24b prevent the tapered rollers 15 inserted in the pocket 16 from slipping out to the outer diameter side OS.

In the pocket 16 in which the guide claws 24b extend to the outer diameter side OS, a gradient α is provided so that the spacing between the columns widens toward the inner diameter side IS, and in the pocket 16 in which the guide claws 24a extend to the inner diameter side IS, a gradient α is provided so that the spacing between the columns widens toward the outer diameter side (the other radial direction) OS. In the pocket 16 in which the gradient α is provided so that the spacing between the columns widens toward the inner diameter side IS, the pocket has an R shape that becomes larger toward the inner diameter side IS. In the pocket 16 in which the gradient α is provided so that the spacing between the columns widens toward the outer diameter side OS, the pocket has an R shape that becomes larger toward the outer diameter side OS.
This retainer segment 20 also has an R shape that becomes larger toward the inner diameter side IS or the outer diameter side OS at some or all of the corners Cr of the pocket 16, so that stress concentration is reduced more than in a typical retainer segment. Otherwise, the retainer segment has the same configuration as described above and provides the same functions and effects as described above.

[Third embodiment: Figs. 7 to 22]
As shown in FIG. 7 , in this embodiment, a connecting member 25 for connecting a plurality of retainer segments 20 is detachably provided to an engaging portion 27 provided on each retainer segment 20 .
In this embodiment, as shown in Figure 8, six column sections 23 are provided in one segment 20, and five pockets 16 for accommodating tapered rollers 15 (Figure 7) are provided between adjacent column sections 23. On the outer diameter side of the opposing surfaces of adjacent column sections 23 that form each pocket 16, guide claws 24 are provided to prevent the tapered rollers 15 (Figure 7) inserted in the pocket 16 from slipping out to the outer diameter side.

The cage 17 (FIG. 7) formed by arranging the segments 20 in an annular shape is of an outer ring guide type. Arc-shaped guide projections (projections) 29 are provided on both axial ends of the column portion 23, i.e., on the outer surfaces of both axial ends. The guide projections 29 may be provided only on any of the column portions 23, including the column portions 29 at both ends.
The segment 20 is arranged in an annular shape with the end faces of the small diameter side arcuate portion 21 and the large diameter side arcuate portion 22 abutting against each other.

Protrusions 26 are provided on both ends of the large diameter side surface of the large diameter side arcuate portion 22 of the segment 20 so as to protrude in the axial direction. The protrusions 26 have an engagement portion 27 that engages the connecting member 25. As shown in FIG. 7, the connecting member 25 arranged on the large diameter side of each annularly arranged segment 20 is detachably provided on the engagement portion 27. As shown in FIG. 8, it is preferable that the protrusions 26 on both ends of the large diameter side arcuate portion 22 are provided so as to avoid contact between the protrusions 26 of adjacent segments 20.

<About the ring jig>
17, the annular jig 31 has a ring portion 31a that abuts against the small diameter end face of the inner ring 11, and an L-shaped engaging portion 31b that protrudes from the axial end of the ring portion 31a toward the outer diameter side. When the large diameter sides of the segments 20 arranged in an annular shape are connected by the connecting member 25, the engaging portion 31b is fitted into the wing portion 28 of the segment 20 with the ring portion 31a abutting against the small diameter end face of the inner ring 11.

<Connecting parts, etc.>
As shown in FIG. 10, the connecting members 25 wound around the large diameter side of each segment 20 are fastened by a fastening member 30 such as a turnbuckle. When the fastening member 30 is configured as a turnbuckle, the turnbuckle has a body portion with an internal thread, and the ends of the connecting members 25 can be connected to each other by screwing a male thread portion provided at the end of the fastening member 30 into this body portion. By rotating the body portion, tension can be applied to the connecting members 25, and by rotating the body portion in the opposite direction to the tightening direction, the fastening of both ends of the connecting members 25 can be released. The ends of the connecting members 25 can be connected to each other by providing a fastening portion at the end of the connecting members 25 and winding the connecting members 25 together, or by using a cable tie.

A wire or a belt may be used as the connecting member 25. When a wire is used as the connecting member 25, a detachable hook or a turnbuckle may be used as the fastening member 30. A turnbuckle is most preferable because it is detachable, the fastening force does not loosen, and the fastening force is adjustable. When a belt is used as the connecting member 25, a detachable buckle is preferable as the fastening member 30 because the fastening force does not loosen.
The segment 20 in Fig. 8 is made of resin. The resin for forming the segment 20 may be polyetheretherketone mixed with carbon fiber or polyetheretherketone mixed with glass fiber.

<Assembling tapered roller bearings using segments>
Before assembling the tapered rollers etc. into the outer ring 12 of FIG. 7, an inner ring assembly in which the inner ring 11, tapered rollers 15 and cage 17 are integrated is assembled as shown in FIGS.
To assemble the inner ring assembly, first, the tapered rollers 15 are arranged on the raceway surface 13 of the inner ring 11 with the large end face of the inner ring 11 facing down, as shown in Figs.

If tapered rollers 15 are arranged on raceway surface 13 with the large end face of inner ring 11 facing down, there is a possibility that tapered rollers 15 will fall off from inner ring 11 due to their own weight. To prevent tapered rollers 15 from falling off inner ring 11, the distance from the central axis of inner ring 11 to the tip of large rib portion 19 is made greater than the distance from the central axis of inner ring 11 to the center of gravity of tapered roller 15, and diameter J of large rib portion 19 satisfies the following formula.
(J/2)-HCOSI>y1

In other words, as shown in Figure 14, with the tapered rollers 15 arranged on the raceway surface 13 with the large end face of the inner ring 11 facing down, if the angle between the side of the large rib portion 19 that contacts the tapered roller 15 and the line perpendicular to the central axis of the inner ring 11 is I, the chamfer width of the tip of the large rib portion 19 is H, the distance from the central axis of the inner ring 11 to the center of gravity of the tapered roller 15 is y1, and the diameter of the large rib portion 19 is J, then if the above formula is satisfied, the tapered rollers 15 can be prevented from falling off. In Figure 14, D is the diameter of the large end face of the tapered roller 15, G is the diameter of the small end face of the tapered roller 15, F is the length of the tapered roller 15, and E is the distance from the central axis to the end of the raceway surface 13 on the large rib portion 19 side.

After the tapered rollers 15 are lined up on the raceway surface 13 of the inner ring 11, as shown in FIG. 15, each segment 20 is successively placed on top of the raceway surface 13 from the outer diameter side, and the tapered rollers 15 are inserted into the pockets 16 (FIG. 12) from the inner diameter side of each segment 20.
16 and 17, an annular jig 31 is fitted onto the wing portions 28 protruding from the small diameter side surfaces of the annularly arranged segments 20, and a connecting member 25 is passed through the engaging portion 27 of the protrusions 26 protruding from the large diameter side surfaces. Furthermore, the ends of the connecting members 25 wound around the outer diameter sides of the segments 20 are bound together with fastening members 30. The connecting members 25 are tightened with the fastening members 30 to integrate the multiple annularly arranged segments 20.

The fastening member 30 is located between the protruding parts 26 that protrude from both ends of the large diameter side surface of the large diameter arcuate part 22, and the space between the protruding parts 26 on both ends forms an accommodation portion for the fastening member 30.
The connecting member 25 may be a single continuous member in the circumferential direction, or may be divided into a plurality of members in the circumferential direction, with the ends of each divided connecting member 25 being connected to each other by fastening members 30. When the connecting member 25 is divided into a plurality of members, it is preferable that the fastening members 30 are equally spaced circumferentially.

When the connecting member 25 is wound around the outer circumference of the annularly arranged segments 20 and the connecting member 25 is tightened with the fastening member 30, the small diameter side of the annularly arranged segments 20 tends to open up. In order to prevent the small diameter side from opening up, an annular jig 31 is fitted into the wing portion 28 on the small diameter side of the annularly arranged segments 20 when tightening the connecting member 25.

As shown in FIG. 17, the annular jig 31 is fitted axially onto the wing portions 28 of the small-diameter arc-shaped portions 21 of the segments 20 arranged in an annular shape, and after the inner ring assembly is assembled, it can be removed by moving it along the central axis (FIG. 18).
Next, the inner race assembly is assembled into the outer race 12 by turning it over so that the small diameter side of the inner race assembly faces downward, as shown in FIG.

When this inner race assembly is assembled into the outer race 12, even if the inner race assembly is turned over with the small diameter side facing downward, the segments 20 arranged in an annular shape are connected at their outer peripheries by the connecting member 25, so that the segments 20 will not come apart.
The tapered rollers 15 inserted into the pockets 16 of the segments 20 are also prevented from slipping out of the pockets 16 by the guide pawls 24 (FIG. 8) provided on the outer diameter side of the pillars 23 that form the pockets 16 .

The annular jig 31 (FIG. 17) used when assembling the inner race assembly is to be removed when assembling the outer race 12.
Even if the annular jig 31 (Figure 17) is removed and the inner ring assembly is turned over with the small diameter side facing downward, each segment 20 connected by the connecting member 25 has its tapered roller 15 inserted and held in the pocket 16 of each segment 20 sandwiched between the large rib portion 19 and the small rib portion 18 located on both axial sides of the raceway surface 13 of the inner ring 11, and the tapered roller 15 is caught on the small rib portion 18 of the inner ring 11, so that the segments 20 are prevented from falling off.

The height of the small flange portion 18 of the inner ring 11 that prevents each segment 20 from falling off satisfies the following conditions.
When the tapered roller 15 fitted between the large rib portion 19 and the small rib portion 18 of the inner ring 11 rotates, if the large end face of the tapered roller 15 is not in contact with the large rib portion 19, the tapered roller 15 rotates about point A, as shown in the schematic diagram of Figure 21. If the large end face of the tapered roller 15 is in contact with the large rib portion 19, it is considered that the tapered roller 15 rotates about point B.

When the large end face of tapered roller 15 contacts large rib portion 19 and rotates about point B, if diameter M of small rib portion 18 of inner ring 11 is sufficiently large, the small diameter side end face of tapered roller 15 will contact point C on the side surface of small rib portion 18, as shown in the schematic diagram of Figure 22. This restricts the rotation of tapered roller 15, and tapered roller 15 will get caught on small rib portion 18 of inner ring 11.
Point C on the side of small rib portion 18 at which tapered roller 15 catches is the intersection point between the spline curve that traces the trajectory of the small end face corner of tapered roller 15 when tapered roller 15 rotates and the side of small rib portion 18, and at this time, diameter M of small rib portion 18 of inner ring 11 satisfies the following condition.
(M/2)-KcosL>y3

Here, the diameter of the small rib portion 18 of the inner ring 11 is M, the angle that the side surface of the small rib portion 18 of the inner ring 11 on the point C side makes with a line perpendicular to the central axis of the inner ring 11 is L, the chamfer width of the tip of the small rib portion 18 is K, and the distance from the contact point C where the side surface of the small rib portion 18 and the small diameter end face of the tapered roller 15 come into contact with each other to the central axis when the tapered roller 15 is rotated around point B at the tip of the large rib portion 19 of the inner ring 11 is y3.

As described above, by turning the inner ring assembly over so that the small diameter side faces downward and installing it into the outer ring 12, the tapered roller bearing 1 can be assembled as shown in FIG.
When the assembly of the tapered roller bearing 1 is complete, the tapered roller bearing 1 can be installed in the device and then the connecting members 25 fastening the outer periphery of each segment 20 can be removed. This is because, after the assembly of the tapered roller bearing 1 is complete, the segments 20 will not come apart even if the fastening members 30 (FIG. 10) are loosened and removed.

In the third embodiment, a wing portion 28 that protrudes toward the small diameter side is provided on the small diameter side surface of the small diameter side arcuate portion 21, and when the large diameter side of each annularly arranged segment 20 is bound with a connecting member 25, an annular jig 31 is fitted into the wing portion 28 on the small diameter side of each annularly arranged segment 20. This retainer segment 20 also has an R shape that becomes larger toward the inner diameter side or the outer diameter side in part or all of the corner portion Cr of the pocket 16, so that stress concentration is reduced more than in a typical retainer segment. Otherwise, it has the same configuration as above and provides the same effects as above.

The resin retainer segments are formed using a mold or the like, but can also be formed by machining or using a 3D printer.
The tapered roller bearing of each embodiment can also be applied to a tapered roller bearing having an outer diameter of 1 m or less. The tapered roller bearing of each embodiment may be applied to applications other than wind power generation equipment or industrial machinery.
The tapered roller bearing of each embodiment may be applied to a double-row tapered roller bearing.

<Application to wind power generation equipment>
Fig. 23 shows an example of a wind power generator using a tapered roller bearing 1 according to any one of the embodiments. In this wind power generator, a main shaft 53 of a propeller-type wind turbine 52 is rotatably supported by a tapered roller bearing 1, which is a main shaft bearing, in a nacelle 51 that is installed on the upper end of a support 50 so as to be able to rotate horizontally. The main shaft bearing is a large bearing with an outer diameter of 1 m or more. The main shaft 53 is connected to a generator 54 via a gearbox 55. The tapered roller bearing 1 according to the embodiment is used for the main shaft bearing in this wind power generator.
In this case, the tapered roller bearing 1 with improved strength of the retainer segments can be applied to large bearings used in wind power generation equipment, and the maintenance costs, etc. of the tapered roller bearing 1 can be reduced.

Although the embodiments of the present invention have been described above, the embodiments disclosed herein are illustrative in all respects and are not limiting. The scope of the present invention is indicated by the claims rather than the above description, and is intended to include all modifications within the meaning and scope of the claims.

Reference Signs List 1: Tapered roller bearing, 11: Inner ring, 12: Outer ring, 15: Tapered roller, 16: Pocket, 17: Cage, 20: Cage segment, 21, 22: Arc-shaped portion, 23: Column portion, 24: Guide claw, 25: Connecting member, 27: Engagement portion, 32: Small diameter side engagement portion (engagement portion), 33: Connecting member,
Corner: Cr, sf: surface

Claims (6)

The bearing comprises inner and outer rings, a plurality of tapered rollers interposed between the inner and outer rings, and a cage for holding the tapered rollers, the cage including a plurality of cage segments arranged in an annular shape,
the retainer segment includes a plurality of column portions extending in an axial direction and a pair of arc-shaped portions extending in a circumferential direction and connecting the plurality of column portions, respectively; and a pocket for holding the tapered rollers is formed between adjacent column portions of the plurality of column portions and the pair of arc-shaped portions,
A tapered roller bearing in which the surface of the arc-shaped portion or the column portion that constitutes the pocket is inclined with respect to the radial direction of the pocket of the retainer segment, and part or all of the corners of the pocket have an R-shape that becomes larger toward one side or the other in the radial direction. A tapered roller bearing as described in claim 1, in which the retainer segments are made of resin. A tapered roller bearing according to claim 2, in which the retainer segments are made of resin containing carbon fiber or glass fiber. A tapered roller bearing according to claim 2 or claim 3, in which the retainer segments are formed by injection molding. The tapered roller bearing according to claim 1 or 2 is a large-sized tapered roller bearing with an outer diameter of 1 m or more used in wind power generation equipment. 3. A tapered roller bearing according to claim 1 or claim 2, wherein guide claws that enable the tapered rollers to be inserted into pockets from the inner diameter side of the retainer segment are provided on the outer diameter side of adjacent column portions, and connecting members that connect a plurality of the retainer segments are removably provided on engaging portions provided on each of the retainer segments.

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