JP2007321939A - Bearing assembling method, rolling bearing, and cage for bearing - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technology for operating a bearing incorporated with a cage stably for a long time without reducing the strength of the cage. <P>SOLUTION: In this bearing assembling method, the bearing is constituted by providing the resin-made cage revolving while holding a plurality of rolling elements (rollers) 5 incorporated along a section between raceway surfaces 1s and 3s of inner and outer rings 1, 3 so as to roll freely, holding each rolling element in the cage so as to rotate freely centered on a rotary symmetrical axis Z to form a cross section crossing the rotary symmetrical axis orthogonally into a circular shape, and protruding annular collars (the small diameter collar 7, the large diameter collar 9) for holding and guiding the plurality of rolling elements along the raceway surfaces on either of the inner and outer rings and at least on one side of both raceway surfaces. When incorporating the plurality of rolling elements into the inner ring formed by protruding the small diameter collar together with the cage, the cage is heated and thermally expanded to incorporate each rolling element held in the cage into the raceway surface of the inner ring by crossing over the protruding end 7e of the small diameter collar part. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an improvement in a method for assembling a bearing, and more particularly to a technique for incorporating a plurality of rolling elements together with a cage into a bearing ring.

  Conventionally, various drive devices such as railway vehicles have been applied with bearings that rotatably support the rotation mechanism, and a plurality of rolling elements incorporated between the inner and outer rings can be freely rotated on the bearings. A retainer having a plurality of pockets to be held on is provided. As such a bearing, there are a ball bearing that is applied when supporting a relatively small load and a roller bearing that is applied when supporting a relatively large load, which corresponds to high-speed rotation under a high load in recent years. For this reason, roller bearings are often used.

  In the roller bearing, for example, a cage as shown in Patent Document 1 is incorporated together with rolling elements (rollers). As an example of such a configuration, in FIG. 1A, a rotationally symmetric axis Z of a plurality of rolling elements (rollers) 5 is a central axis Q (see FIG. c))) Tapered roller bearings designed to focus on one point are shown. The roller bearing includes a raceway (inner ring 1 and outer ring 3) arranged opposite to each other so as to be relatively rotatable, and a raceway surface 1s, 3s formed continuously on the opposing surfaces of the inner and outer rings 1, 3 in the circumferential direction. A plurality of rolling elements (rollers) 5 incorporated so as to be freely rotatable along the inner circumference and the plurality of rolling elements (rollers) 5 are revolved along the inner and outer rings 1 and 3 while being rotatably held one by one. A resin cage is provided.

  In such a configuration, an annular flange protrudes along the raceway surfaces 1s, 3s on at least one side of either one of the inner and outer rings 1, 3 and both raceway surfaces 1s, 3s. In the drawing, a configuration in which annular flanges 7 and 9 protrude on both sides of the raceway surface 1s of the inner ring 1 is illustrated. Thus, when the plurality of rolling elements (rollers) 5 roll between the raceway surfaces 1s, 3s of the inner and outer rings 1, 3, each rolling element (roller) 5 is guided by the guide surface 7s of the annular flanges 7, 9. , 9s, and guided along the raceway surfaces 1s, 3s of the inner and outer rings 1, 3. At this time, each rolling element (roller) 5 is held one by one in a plurality of pockets 8 formed in the cage and rotates about the rotational symmetry axis Z.

  Further, the raceway surfaces 1 s and 3 s of the inner and outer rings 1 and 3 are inclined along the focusing direction of the rotational symmetry axis Z of each rolling element (roller) 5, and correspondingly, the raceway surface 1 s of the inner ring 1. The ring-shaped flange portions 7 and 9 protruding on both sides of the protrusions 7e and 9e have different diameters. That is, one of the flanges 9 (hereinafter referred to as the large diameter flange 9) serves as a relatively large-diameter protruding end 9e, and the other flange 7 (hereinafter referred to as the small diameter flange 7) corresponds to the one flange 9. The protruding end 7e has a relatively small diameter.

  Further, the cage includes two annular portions 2, 4 which are continuous in the circumferential direction between the inner and outer rings 1, 3 and are opposed to each other at a predetermined interval at the same center. , 4 and a plurality of column portions 6 that are arranged at equal intervals in the circumferential direction along the annular portions 2, 4, and each pocket 8 includes two annular portions. 2 and 4 and a plurality of pillars 6 are defined. In this case, the two annular portions 2, 4 are designed to have different diameters along the inclination direction of the raceway surfaces 1s, 3s of the inner and outer rings 1, 3. That is, one annular part (large diameter side annular part) 4 is designed to have a relatively larger diameter than the other annular part (small diameter side annular part) 2. The whole has a truncated cone shape.

  When assembling such a tapered roller bearing, for example, as shown in FIG. 1 (b), after rolling elements (rollers) 5 are held in the respective pockets 8 of the cage, the annular small-diameter flanges 7 are respectively attached. The inner ring 1 is moved in the arrow Y direction so as to be positioned on the rolling elements (rollers) 5. At this time, the small-diameter flange 7 enters the inside of each rolling element (roller) 5 in which the rotational symmetry axis Z is converged and arranged toward the rotation center axis Q of the bearing (FIG. 1 (c)). Thereafter, the inner ring 1 is further moved in the direction of the arrow Y due to the height difference G between the annular surface 7m of the protruding end 7e of the small diameter flange 7 and the rolling surface 5m of each rolling element (roller) 5. It becomes a state that can not be.

  In this state, in order to incorporate a plurality of rolling elements (rollers) 5 together with the cage into the raceway surface 1 s of the inner ring 1, each rolling element (roller) 5 gets over the protruding end 7 e of the small-diameter flange 7 and the raceway surface. It will be incorporated into 1s. At this time, a force is applied to the small-diameter-side annular portion 2 of the cage to push and expand the small-diameter-side annular portion 2 in the outer diameter direction, but the small-diameter-side annular portion 2 has a truncated cone shape. The formed cage has a wide flange shape in the radial direction, and exhibits higher rigidity than the large-diameter side annular portion 4. In this case, most of the force applied to the cage when the rolling elements (rollers) 5 are moved over the projecting end 7e of the small-diameter flange 7 and incorporated into the raceway surface 1s is the large-diameter side annular portion having a low rigidity. 4, and attempts to spread the large-diameter side annular portion 4 in the outer diameter direction. For this reason, it has been difficult to incorporate the rolling elements (rollers) 5 into the raceway surface 1 s of the inner ring 1.

Therefore, for example, in Patent Document 1, by reducing the holding portion on the small diameter side of the cage (small diameter side of each column portion 6), when each rolling element (roller) 5 is assembled, the small diameter side of the cage A technique has also been proposed that can be expanded in the outer diameter direction. However, if the holding portion on the small diameter side (small diameter side of each column portion 6) of the cage is reduced in this way, it becomes difficult to maintain the strength of the cage constant, and depending on the use state and environment of the bearing. In such a case, there is a possibility that the cage is deteriorated or worn out at an early stage. If it becomes so, it will become difficult to operate stably the bearing in which the said holder | retainer was integrated over a long period of time.
JP-A-8-247152

  The present invention has been made in order to solve such a problem, and an object of the present invention is to stably operate a bearing incorporating the cage over a long period of time without reducing the strength of the cage. It is to provide possible technology.

  In order to achieve such an object, the present invention is capable of rolling along a raceway that is disposed so as to be relatively rotatable and a raceway surface that is continuously formed in a circumferential direction on a facing surface of the raceway. Each of the rolling elements has a rotationally symmetric axis, and includes a plurality of incorporated rolling elements and a resin cage that revolves along the raceway while holding each of the rolling elements rotatably one by one. The cross section perpendicular to the rotational symmetry axis is circularly held at the center and rotatably held in the center, and at least one side of the raceway and at least one of the raceway surfaces are arranged on the raceway surface. A method for assembling a bearing in which a ring-shaped flange portion that holds and guides a plurality of rolling elements is protruded along a bearing ring that protrudes the ring-shaped flange portion together with a cage. When assembling, the cage is heated and thermally expanded. The rolling elements held in lifting device ride over a protruding end of the flange portion incorporating the raceway surface of the bearing ring.

  In the present invention, when incorporating a plurality of rolling elements together with the cage into the raceway ring from which the annular flange protrudes, the cage is heated in advance and thermally expanded, and then a plurality of rolling elements are mounted on the cage. The moving body is held, and in this state, each rolling body gets over the protruding end of the flange and is incorporated into the raceway surface of the raceway. In this case, when incorporating a plurality of rolling elements together with the cage into the raceway from which the annular collar protrudes, the plurality of rolling elements previously held by the cage are positioned with respect to the annular collar. In this state, the rolling elements, the cage, and the race ring from which the flange is projected are heated at the same time to thermally expand the cage. You may make it incorporate in the track surface.

  Further, in the rolling bearing assembled by the above-described bearing assembling method of the present invention, the projecting end of the annular flange portion is continuously widened along the direction of assembling the rolling elements into the raceway surface. An inclined tapered surface having a predetermined inclination angle is formed. In this case, the inclination angle of the tapered surface is defined by the angle formed by the central axis passing through the center of rotation of the race and the tapered surface. In addition, you may form the cyclic | annular straight surface extended only a predetermined amount in parallel with the center axis | shaft of a bearing ring in the site | part nearest to a raceway surface among taper surfaces.

  ADVANTAGE OF THE INVENTION According to this invention, the technique which can operate | move the bearing incorporating the said holder | retainer stably over a long period of time can be implement | achieved, without reducing the intensity | strength of a holder | retainer.

  Hereinafter, a bearing assembly method and a rolling bearing according to an embodiment of the present invention will be described with reference to the accompanying drawings. Examples of bearings include, for example, a bearing that supports a rotating shaft provided in a railway vehicle, an automobile, or various industrial and industrial devices. Here, as an example, the bearing is provided in a high-speed railway vehicle such as a Shinkansen. Assume a bearing that supports a rotating shaft (for example, an axle) and an output shaft of the main motor. As a bearing, a radial bearing or a thrust bearing can be applied, but here, as an example, a radial bearing including an inner ring and an outer ring that are disposed to face each other in the radial direction so as to be relatively rotatable with each other is assumed.

  In the present embodiment, description will be made assuming the tapered roller bearing shown in FIGS. 1A and 1B, but description of the contents already described will be omitted. In this case, as the rolling element (roller) 5, for example, a cylindrical roller, a needle roller, a tapered roller, a spherical roller, a convex roller, or the like can be applied. The convex roller is applied to a self-aligning roller bearing in which this is incorporated in two rows. Regardless of which is applied, the rolling element (roller) 5 is held by the cage so as to be rotatable about the rotational symmetry axis Z, and the cross section perpendicular to the rotational symmetry axis Z forms a circle, and in the circumferential direction. It consists of a continuous rolling surface 5m (a circumferential surface that rolls while sliding along the raceway surfaces 1s and 3s of the inner and outer rings 1, 3) and circular side surfaces 5e on both sides (FIG. 1 (b)). .

  An annular end surface that is continuous along the circumferential direction is formed between the rolling surface 5m and the side surface 5e, and a predetermined chamfer 5r is provided here. In this case, the chamfer 5r is applied to reduce wear or wear of the raceway surfaces 1s, 3s of the inner and outer rings 1, 3 and the rolling elements (rollers) 5 when rolling between the inner and outer rings 1, 3. Since the dimensions of the chamfer 5r are arbitrarily set according to the raceway surfaces 1s, 3s of the inner and outer rings 1, 3 and the shape and material of the rolling elements (rollers) 5, for example, numerical values are limited here. Don't do it.

  FIG. 3A illustrates the overall configuration of the cage incorporated in the tapered roller bearing shown in FIGS. 1A and 1B. In the cage, a plurality of column portions are illustrated. 6 extends between the small-diameter-side annular portion 2 and the large-diameter-side annular portion 4, and both end portions 6 e are joined to the respective annular portions 2, 4. In this case, the two annular portions 2 and 4 and the plurality of column portions 6 may be integrally formed at the time of molding the cage, or the plurality of column portions 6 may be formed separately, and both end portions 6e thereof. May be retrofitted to the ring parts 2 and 4.

  As a method for retrofitting, various methods such as bonding, welding, fitting, and screwing the both end portions 6e of each column portion 6 to the annular portions 2, 4 can be applied. There is no particular limitation here. Further, the material of the cage (the annular portions 2 and 4 and the column portion 6) is not limited to resin, and a metal material that exhibits thermal expansion by heating may be applied. Further, as the type of cage, for example, a rice brace cage, a corrugated cage, a crown cage, a cage cage, a mating cage, etc. can be applied.

  In the present embodiment, in the assembly method of FIG. 1B described above, with respect to the bearing ring (inner ring 1 in the drawing) from which the annular flanges (small-diameter flange 7 and large-diameter flange 9) protrude. When a plurality of rolling elements (rollers) 5 are assembled together with the cage, the rolling elements (rollers) 5 held by the cage are heated and thermally expanded by heating the cage, so that the protruding end 7e of the flange portion 7 is provided. Can be incorporated into the raceway surface 1 s of the inner ring 1. In this case, as the heating timing of the cage, for example, before holding the plurality of rolling elements (rollers) 5, only the cage is heated and thermally expanded in advance, and then the plurality of rolling elements (rollers) are placed in the cage. ) 5 is held, and in this state, each rolling element (roller) 5 gets over the protruding end 7e of the flange portion 7 and is incorporated into the raceway surface 1s of the inner ring 1.

  Here, as the amount of thermal expansion of the cage, for example, the entire cage may be enlarged to the extent that the height difference G as described in the assembly method of FIG. The height difference G refers to the amount that each rolling element (roller) 5 gets over the protruding end 7e of the small-diameter flange 7 when the cage is not heated. In another way, when the cage is not heated, when the plurality of annularly arranged rolling elements (rollers) 5 get over the protruding end 7e of the annular small-diameter flange 7, each rolling element (roller) 5 Is expanded in the outer diameter direction, but the amount of expansion in the outer diameter direction at this time can also be expressed as a height difference G.

  By thermally expanding the cage in this manner, each rolling element (roller) 5 can be smoothly incorporated into the raceway surface 1s of the inner ring 1 without causing the rolling end (roller) 5 to interfere with the protruding end 7e of the small diameter flange portion 7. At this time, no interference such as friction or collision occurs between each rolling element (roller) 5 and the protruding end 7e of the small-diameter flange 7, so that each rolling element (roller) 5 or inner ring 1 (small-diameter flange 7). ) Will not be damaged or damaged. Further, at this time, since no external force acts on each rolling element (roller) 5 from the protruding end 7e of the small-diameter flange portion 7, it is possible to eliminate stress (pressure) on the cage during assembly. . As a result, there is no problem such as deformation or breakage of the cage itself due to the stress (pressure). Therefore, according to the bearing in which the plurality of rolling elements (rollers) 5 are incorporated together with the cage by the bearing assembling method of the present embodiment, the bearing can be stably operated over a long period of time.

  In addition, the cage that has been thermally expanded by heating, after each rolling element (roller) 5 is incorporated in the raceway surface 1s of the inner ring 1, is allowed to cool as it is, or is cooled by an existing cooling device or the like. By doing so, it is possible to return to the initial state before heating. As a result, the plurality of rolling elements (rollers) 5 are stably incorporated into the raceway surface 1s of the inner ring 1 in a state where the rolling elements (rollers) 5 are rotatably held one by one by the cage. At this time, the rolling surface 5 m of each rolling element (roller) 5 can be accurately seated on the raceway surface 1 s of the inner ring 1. After that, by assembling the outer ring 3, the plurality of rolling elements (rollers) 5 assembled between the inner and outer rings 1 and 3 together with the cage are stabilized along the raceway surfaces 1 s and 3 s of the inner and outer rings 1 and 3. As a result, the rotation performance of the bearings (inner and outer rings 1, 3) can be kept constant over a long period of time.

  Moreover, about the heating timing of a holder | retainer, it is not limited to embodiment mentioned above, You may set to the following timings. FIG. 1 (c) shows an explanatory view of another embodiment of the bearing assembling method. First, a plurality of rolling elements (rollers) 5 previously held by a cage are projected from the small-diameter flange 7. Position relative to the end 7e. In this state, the rolling elements (rollers) 5 and the cage and the inner ring 1 from which the small-diameter flange portion 7 is projected are simultaneously heated to thermally expand the cage. At this time, each rolling element (roller) 5 gets over the protruding end 7 e of the small-diameter flange portion 7 and is incorporated into the raceway surface 1 s of the inner ring 1.

Such a bearing assembling method utilizes a difference in linear expansion coefficient between the resin cage, the steel rolling elements (rollers) 5 and the inner ring 1. In this case, since the linear expansion coefficient of the resin is larger than that of the steel material, the amount of thermal expansion of the cage is larger than that of the rolling elements (rollers) 5 and the inner ring 1. Thereby, the same effect as the above-described embodiment (FIGS. 1A and 1B) can be realized. In addition, since the said effect has already been demonstrated, the description is abbreviate | omitted.
In each of the above-described embodiments (FIGS. 1A to 1C), the heating temperature and heating time for heating the cage are, for example, the shape and size of the cage, material (type of resin) ) Or the like, and is not particularly limited here.

The present invention is not limited to the above-described embodiments, and the following modifications are also included in the technical scope of the present invention.
As a first modification, as shown in FIG. 2A, the annular surface 7m may be formed as a tapered surface 7m having a predetermined inclination angle α at the protruding end 7e of the annular small-diameter flange portion 7. The taper surface 7m is formed by continuously inclining in a divergent shape along the direction in which each rolling element (roller) 5 is assembled to the raceway surface 1s of the inner ring 1.

  Here, the inclination angle α of the tapered surface 7m is defined by the angle formed between the rotation center axis Q passing through the rotation center of the raceway ring (inner ring 1) and the taper surface 7m. In this case, the inclination angle α may be set to, for example, an angle (FIG. 2A) formed by the rolling surface 5m of each rolling element (roller) 5 and the central axis Q in a state of being held by the cage. Alternatively, the angle formed between the raceway surface 1s of the inner ring 1 and the central axis Q (FIG. 1 (c)) may be set. In any case, the inclination angle α is, for example, the type and size of the rolling element (roller) 5 and the shape thereof, or the shape and size of the bearing ring (inner ring 1), the size of the protruding end 7e of the small-diameter flange 7 and the like. Since the optimum angle is set according to the shape and the like, there is no particular numerical limitation here.

  As described above, according to the first modification, by forming the tapered surface 7m on the protruding end 7e of the small-diameter flange portion 7, in each of the above-described embodiments (FIGS. 1A to 1C), a plurality of When the rolling elements (rollers) 5 are incorporated into the raceway surface 1s of the inner ring 1, each rolling element (roller) 5 is guided along the taper surface 7m, so that all the rolling elements (rollers) 5 do not vary. And can be accurately incorporated into the raceway surface 1s. As a result, the assembly work is facilitated, and the assembly efficiency of the bearing can be dramatically improved.

  Further, as shown in FIG. 2 (b) as a second modification, the rotation center axis Q of the inner ring 1 (bearing) is located at a portion (also referred to as an edge portion) closest to the raceway surface 1s in the tapered surface 7m described above. Alternatively, an annular straight surface 7mp may be formed that extends in parallel with a predetermined amount. In this case, the formation width δ of the straight surface 7mp is arbitrarily set in accordance with, for example, the shape and size of the inner ring 1 or the shape and size of the protruding end 7e of the small-diameter flange portion 7, and is particularly numerical here. There is no limitation.

  As described above, according to the second modification, at the protruding end 7e of the small-diameter flange portion 7, the straight surface 7mp is formed on the tapered surface 7m, so that the plurality of rolling elements (rollers) 5 are connected to the raceway surface 1s of the inner ring 1. When the rolling elements (rollers) 5 are incorporated into the rolling elements, it is possible to prevent the rolling elements (rollers) 5 from interfering with the edge portion and causing the rolling elements (rollers) 5 to be damaged or worn, for example. In addition, by performing various finishing processes (for example, L3 processing, grinding process, etc.) on the straight surface 7mp after the heat treatment for the inner ring 1, it becomes possible to eliminate the variation in the dimensions of the small-diameter flange portion 7, and as a result, The yield of the inner ring 1 can be improved.

Further, the following new configurations are provided for the above-described embodiments (FIGS. 1A to 1C) and the first and second modifications (FIGS. 2A and 2B). It is also possible to add.
That is, FIGS. 3 to 5 show a bearing retainer according to a third modification of the present invention. In such a retainer, each pocket 8 has an annular portion 2,4. Among them, a relief portion 10 is provided which is formed by recessing a portion adjacent to both end portions 6e of the column portion 6 by a predetermined depth. In this case, the relief portions 10 are provided at the four corners of each pocket 8 and are formed to be recessed (recessed) in a direction along the rotation center axis Q (FIG. 1C) of the bearing. In other words, each relief portion 10 is not formed to be recessed (recessed) along the bearing rotation direction.

  More specifically, as shown in FIGS. 3B to 3D, the escape portion 10 has a flat surface 10s formed flat across the annular portions 2 and 4 and a flat surface. It is composed of two arcuate surfaces R1 and R2 that are continuous with a predetermined curvature (for example, a radius of curvature) from both sides of the surface 10s toward the annular portions 2 and 4 and the column portion 6. Here, the flat surface 10s is formed so as to cross the annular portions 2, 4 in parallel along the direction orthogonal to the rotation center axis Q of the bearing, and the two arc-shaped surfaces R1, R2 are One arcuate surface R1 is continuous from one side of the flat surface 10s to the inner peripheral surfaces 2s and 4s of the annular portions 2 and 4, and the other arcuate surface R2 is the other side of the flat surface 10s. To the inner wall surface 6 s of the column portion 6.

  In such a relief portion 10, assuming that the overall width dimension from the two arcuate surfaces R1, R2 to one flat surface 10s is 2n, the width dimension 2n is the rolling element (roller) 5 (FIG. 1 ( The dimension is set larger than the dimension of the chamfer 5r (FIG. 1 (a)) formed on the end face of a)). Further, the relief portion 10 is configured by setting the depth dimension k within a range of 10% to 30% of the width dimension H of the annular portions 2 and 4. Here, assuming that the depth dimension k of the relief portion 10 approximates the curvature radius ρ of the arcuate surfaces R1 and R2 (ρ = k), the ratio (ρ / H) of the curvature radius ρ and the width dimension H In terms of representation, the clearance 10 is set so as to satisfy the relationship of 0.1 ≦ ρ / H ≦ 0.3.

  In the drawing, each of the arcuate surfaces R1 and R2 is formed with a continuous constant (single) radius of curvature ρ. In this case, the magnitude of the radius of curvature ρ is, for example, the depth of the relief portion 10. Since it is arbitrarily set according to the length dimension k and the width dimension 2n, the numerical value is not particularly limited here. Further, the depth dimension k and the width dimension 2n of the relief portion 10 are arbitrarily set according to, for example, the size and shape of the rolling element (roller) 5 and the size and shape of the pocket 8 that holds the rolling element (roller) 5. Therefore, the numerical values are not particularly limited here.

  As described above, according to the bearing cage of the third modified example, two arcs continuous with a predetermined radius of curvature ρ from both sides of one flat surface 10 s toward the annular portions 2, 4 and the column portion 6. By providing the relief portions 10 formed of surfaces at the four corners of the pocket 8, excessive stress concentration at the four corners of the pocket 8 can be reduced even under a condition in which an increase in the radius of curvature is restricted. As a result, the strength of the cage can be maintained constant as compared with the conventional case, and as a result, the life of the cage can be extended and the reliability can be improved.

  Further, according to the present modification, the width dimension 2n of the relief portion 10 is set to be larger than the dimension of the chamfer 5r formed on the end face of the rolling element (roller) 5, so that the lubricant ( It is possible to prevent scraping of grease and oil) and uneven wear of the pocket 8 of the cage. That is, at the four corners of each pocket 8, it becomes possible to attach and hold the lubricant to the end face of the rolling element (roller) 5, and thereby the end face of the rolling element (roller) 5 and the collar face of the inner and outer rings 1, 3. (In the drawing, the lubricant is always applied to the contact portion with the guide surfaces 7s, 9s (FIGS. 1A, 1B) of the flanges 7, 9 protruding on both sides of the raceway surface 1s of the inner ring 1. Can continue to supply. As a result, it becomes possible to reduce the wear and wear of the rolling elements (rollers) 5 and the inner and outer rings 1 and 3, and to extend the life of the bearing.

  Furthermore, according to the present embodiment, the depth k of the relief portion 10 is set in the range of 10% to 30% of the width H of the annular portions 2 and 4, thereby increasing the strength of the entire cage. It becomes possible to keep constant, and as a result, the rotational performance of the bearing can be kept constant over a long period of time. In particular, the bearings that support the rotating shafts (for example, axles) provided on high-speed railway vehicles such as the Shinkansen and the output shafts of the main motors are subjected to high loads under high-speed rotation. Although a container having a high strength is required, the cage of the present embodiment can sufficiently cope with this.

Here, the effect of the bearing cage of the present embodiment as described above will be demonstrated using a stress generation model.
FIG. 4 (a) shows a cage model in which the pocket 8 (FIG. 3) does not have a relief portion 10, and the annular portions 2, 4 have a thickness dimension T = 8 and a width dimension H = 10. The column portion 6 is set to have a length dimension E = 15 and a column length L = 20 to the center of the annular portion. Then, a load F = 50 (for example, 50 Newton) is applied to the column portion 6 to generate a moment M in the cage model. At this time, it is assumed that a uniform distributed load W acts on the column portion 6.

From the material mechanical relationship under such conditions, the stress σ ₀ (reference stress) generated in the column portion 6 is calculated as the following equation (1) from the following equations (2) and (3).
σ ₀ = M / Z (Z: section modulus) (1)
^{M = W · L 2/2} ... (2)
^{Z = T · H 2/6} ... (3)

FIG. 4 (b) shows a cage model having an existing relief portion 10a in the pocket 8 (FIG. 3). The relief portion 10a is formed at a portion adjacent to the end portion 6e of the pillar portion 6 at a single position. It has an arc shape formed with only one curvature radius ρ. In this case, when the bending stress generated in the annular portions 2 and 4 is obtained from the material mechanical relationship, the tensile stress σmax generated at the four corners of each pocket 8 in consideration of the stress concentration is calculated as Equation (4). The
σmax = ασ ₀ (α: Stress concentration factor) (4)

Here, structural analysis (FEM analysis) based on the finite element method is performed on the cage model of FIG. 4B, and σmax obtained from the analysis result and the reference stress σ ₀ obtained from material mechanics are used. The stress concentration coefficient α is calculated as equation (5).
α = σmax / σ ₀ (5)

  FIG. 5 (a) shows the calculation result of the stress concentration coefficient α in the cage model of FIG. 4 (b). The radius of curvature of the relief portion 10a is ρ, the depth dimension is k, the annular portion 2 is shown. , 4 is H and ρ = k, the stress concentration coefficient α is an extreme value (α = 3.65 to 3.76, αmin = in the range of ρ / H = 0.1 to 0.3). It can be seen that 3.39) is taken.

  FIG. 4 (c) shows a cage model of the present modified example having the existing relief portion 10 in the pocket 8 (FIG. 3), and the width dimension of the relief portion 10 is 2n, ρ / H = 0. When the stress concentration coefficient α is calculated based on this, a calculation result as shown in FIG. 5B is obtained. According to this calculation result, n / ρ = 1.0 is the dimensions (single curvature radius ρ) indicating the minimum value (αmin = 3.39) of the stress concentration coefficient α in FIG. It can be seen that when n / ρ exceeds 1.0, the stress concentration coefficient α decreases, and the effect of reducing stress concentration is exhibited. In this case, since n / ρ = 2.0 or later takes a substantially constant extreme value, it is preferable to set the relief portion 10 so that n / ρ is 2.0 or more.

(a) is sectional drawing which expands and shows a part of bearing assembled with the bearing assembly method which concerns on one embodiment of this invention, (b) is the state which has assembled the bearing of the same figure (a) FIG. 6C is a diagram showing a bearing assembling method according to another embodiment of the present invention. (a) is a disassembled sectional view of the structure of the bearing according to the first modification of the present invention, and a part thereof is enlarged, (b) is a view of the bearing according to the second modification of the present invention. Sectional drawing which expands and shows a structure partially. (a) is a perspective view which shows the example of a whole structure of the bearing retainer which concerns on the 3rd modification of this invention, (b) saw a part of retainer of the same figure (a) from the outside. An enlarged view, (c) is an enlarged view of a part of the cage of FIG. (A) as viewed from the inside, and (d) is an enlarged view showing a configuration of the escape portion. It is a figure which shows the generation | occurrence | production model of stress, Comprising: (a) is a cage model without a relief part in a pocket, (b) is a cage model which has the existing relief part, (c) is a 3rd deformation | transformation. Example cage model. It is a figure which shows the FEM analysis result of stress concentration count, Comprising: (a) is the analysis result in the existing cage, (b) is the analysis result of the cage of the 3rd modification.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Inner ring 1s Inner ring raceway surface 3 Outer ring 3s Outer ring raceway surface 5 Rolling element (roller)
7 Small-diameter flange 7e Projection end 9 Large-diameter flange Z Rotational symmetry axis of rolling element

Claims (10)

A plurality of rolling elements, which are arranged so as to be rotatable relative to each other, a plurality of rolling elements which are rotatably integrated along the raceways formed on the opposing surfaces of the bearing rings in the circumferential direction, and a plurality of rolling elements. Each of the rolling elements is held by the holder so as to be rotatable about a rotationally symmetric axis. A cross section perpendicular to the rotational symmetry axis is circular, and a plurality of rolling elements are held and guided along at least one of the raceways and at least one of the raceways. A method for assembling a bearing in which an annular flange is projected,
When incorporating a plurality of rolling elements together with the cage into the raceway from which the annular flange protrudes, the rolling elements held by the cage are A bearing assembling method, wherein the bearing assembly is mounted on the raceway surface of the raceway over the protruding end of the part.   When incorporating a plurality of rolling elements together with the cage into the raceway ring from which the annular flange protrudes, the cage is heated in advance and thermally expanded, and then the plurality of rolling elements are held in the cage. The bearing assembly method according to claim 1, wherein each rolling element is mounted on the raceway surface of the raceway over the protruding end of the flange in that state.   When incorporating a plurality of rolling elements together with the cage into the raceway from which the annular collar protrudes, the plurality of rolling elements previously held by the cage are positioned with respect to the annular collar, and the state Then, the rolling elements, the cage, and the raceway from which the flange portion protrudes are heated at the same time to thermally expand the cage, and then the rolling elements get over the protruding end of the flange portion and the raceway surface of the raceway ring. The bearing assembly method according to claim 1, wherein the bearing assembly method is incorporated into a bearing assembly. A rolling bearing assembled by the bearing assembling method according to claim 1,
A rolling bearing characterized in that a taper surface having a predetermined inclination angle that is continuously inclined in a divergent shape along the direction of incorporation of each rolling element into the raceway surface is formed at the protruding end of the annular flange portion. .   The rolling bearing according to claim 4, wherein the inclination angle of the tapered surface is defined by an angle formed by a central axis passing through the rotation center of the raceway and the tapered surface.   The annular straight surface extended by a predetermined amount in parallel with the central axis of the raceway ring is formed at a portion closest to the raceway surface among the tapered surfaces. Rolling bearing. A bearing retainer incorporated in the rolling bearing according to any one of claims 4 to 6,
The resin cage includes at least one annular part continuous in the circumferential direction along the inside of the bearing, and extends from the annular part along the inside of the bearing, and along the annular part at a predetermined interval in the circumferential direction. A plurality of arranged pillars, and a plurality of pockets that are partitioned by an annular part and a plurality of pillars, and that hold a plurality of rolling elements rotatably one by one,
Each pocket is provided with a relief portion formed by recessing a portion of the annular portion adjacent to the pillar portion by a predetermined depth,
The escape portion includes one flat surface formed flat across the annular portion, and two arc-shaped surfaces continuous at a predetermined curvature from both sides of the flat surface toward the annular portion and the column portion. A bearing retainer characterized by comprising:   In a bearing in which a roller is applied as a rolling element, the relief portion is configured by setting the overall width dimension from two arcuate surfaces to one flat surface larger than the chamfer dimension formed on the end surface of the roller. The bearing retainer according to claim 7, wherein the bearing retainer is provided.   The bearing retainer according to claim 7 or 8, wherein the escape portion is configured with a depth dimension set in a range of 10% to 30% of a width dimension of the annular portion. The bearing retainer according to any one of claims 7 to 9, wherein the bearing retainer is applicable to a bearing that supports a rotating shaft provided in a railway vehicle.

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