JP2013087844A - Radial roller bearing retainer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To achieve a radial roller bearing retainer 7b which is excellent in assembling workability and whose behavior during use can be stabilized even when the axial size is small.SOLUTION: The retainer 7b is made of a synthetic resin and structured to have a discontinuous part 11a at one place in the circumferential direction. Ends 12c, 12d provided sandwiching the discontinuous part 11a are engaged with each other in a mating manner by an engagement part 13a so as not to be relatively displaced in the axial and radial directions. In addition, axial sizes are made different between a pair of outer diameter side engagement pieces 14c, 14d and a pair of inner diameter side engagement pieces 15c, 15d that structure the engagement part 13a to make a gap (α1) between the end faces in the circumferential direction of the engagement pieces 14c, 15c having larger axial sizes and counterpart faces smaller than a gap (β1) concerning the engagement pieces 14d, 15d having smaller axial sizes. Thereby, a sufficient contact area is secured when opposing end faces 17c, 17d with the discontinuous part 11 interposed therebetween contact with each other, thus solving the problem.

Description

  The present invention relates to an improvement in a radial roller (including a needle) bearing retainer made of a synthetic resin and having a function of elastically expanding the diameter. Specifically, even when a structure having a small axial dimension (width dimension) is adopted, a structure that can stabilize the behavior during use is realized.

  A radial roller bearing 1 as shown in FIGS. 5 to 6 is incorporated in a portion to which a large radial load is applied among the rotation support portions of various mechanical devices. The radial roller bearing 1 includes a cylindrical outer ring raceway 3 provided on an inner peripheral surface of an outer diameter side member 2 such as a housing (or a gear or roller that rotates during use) that does not rotate during use, and a rotary shaft (or A plurality of rollers (needles) 6 are provided so as to be able to roll while being held by a cage 7 between a cylindrical surface-like inner ring raceway 5 provided on the outer peripheral surface of the shaft 4 such as a support shaft).

  Of these, the cage 7 is entirely made of a synthetic resin material in a cylindrical shape. Such a cage 7 includes a pair of rim portions 8 and 8 that are arranged concentrically at intervals in the axial direction, each having an annular shape, and intermittently extending in the circumferential direction. A plurality of column portions 9 and 9 provided in a state of being spanned between both rim portions 8 and 8 are provided. And the part surrounded by the four sides by the column parts 9 and 9 and the said rim | limb parts 8 and 8 adjacent to the circumferential direction as the pockets 10 and 10 for hold | maintaining each said roller 6 so that rolling is possible respectively. Yes. Such a cage 7 is formed between the inner peripheral surface of the outer diameter side member 2 and the outer peripheral surface of the shaft 4 in a state where the rollers 6 are rotatably held in the pockets 10 and 10. The outer diameter side member 2 and the shaft 4 are freely rotatable relative to each other. The cage 7 rotates with respect to the outer diameter side member 2 and the shaft 4 along with the revolving motion of the rollers 6.

  In order to assemble such a radial roller bearing 1, the cage 7 is disposed around the inner ring raceway 5 so that the cage 7 is inserted from the end of the shaft 4, and the inner ring raceway 5 is further inserted. Move in the axial direction to the periphery of. However, in this case, the outer diameter of the outer peripheral surface of the shaft 4 is larger than the inner diameter of the cage 7 at the portion between the end of the shaft 4 and the inner ring raceway 5 in the axial direction. If there is an obstacle such as an outward flange-shaped flange, the obstacle becomes an obstacle, and the cage 7 cannot be moved in the axial direction to the periphery of the inner ring raceway 5.

  Therefore, as a cage that can eliminate such inconvenience, for example, Patent Document 1 describes a cage (split type cage) provided with a discontinuous portion at one place in the circumferential direction. FIG. 7 shows a cage 7a described in Patent Document 1. The cage 7a is made of synthetic resin and has a discontinuous portion 11 at one place in the circumferential direction. Further, the end portions 12a and 12b provided across the discontinuous portion 11 are engaged with each other by the engaging portion 13 so that relative displacement in the axial direction and the radial direction is impossible (concave engagement).

  For this purpose, one set of outer diameter side engaging pieces 14a, 14b and inner diameter side engaging pieces 15a, 15b each extending in the circumferential direction is formed for each of the end portions 12a, 12b. Specifically, of the one end portion 12a, the outer diameter side engaging piece 14a is disposed on the outer half of the outer diameter side half and the inner diameter side of the inner half of the inner diameter side half. Each piece 15a is formed. Further, of the other end portion 12b, the outer diameter side engaging piece 14b is disposed in the other half portion in the axial direction of the outer diameter side half portion, and the inner diameter side engaging piece 15b is disposed in the axial direction half portion of the inner diameter side half portion. Each is formed. In addition, the outer diameter side half and the inner diameter side half of the engaging portion 13 each have a pair of outer diameter side engaging pieces 14a and 14b and a pair of inner diameter side engaging pieces 15a and 15b as shafts. In the same manner, the outer diameter side engaging pieces 14a, 14b and the inner diameter side engaging pieces 15b, 15a are respectively radially connected by the axial half and the other axial half. Engage with. In the illustrated example, the end portions 12a and 12b are not engaged with each other. However, when the retainer 7a is incorporated in a radial roller bearing, the width of the discontinuous portion 11 is as follows. Narrow and engage.

  Further, concave portions 16a and 16b are formed on the peripheral surfaces of the pair of rim portions 8a and 8b, respectively. Specifically, in the outer peripheral surface of one rim portion 8a, recesses 16a and 16a that are recessed inward in the radial direction are formed in portions that are axially aligned with the pockets 10 and 10, and the other rim portion 8a On the inner peripheral surface of the rim portion 8b, concave portions 16b and 16b that are recessed radially outward are formed in portions that are aligned with the pockets 10 and 10 in the axial direction.

  The cage 7a having the above-described configuration is obtained by injecting synthetic resin into a cavity of a mold (axial draw type) constituted by a pair of split molds (mold elements), and then splitting these molds. These are formed by so-called axial draw molding in which they are separated in the axial direction. For this reason, the shape of the mold becomes complicated (a cage made of a radial draw type composed of a pair of mold elements moving in the axial direction and a plurality of mold elements moving in the radial direction). Compared to the above, the manufacturing cost can be kept low.

  In addition, since axial draw molding is performed by moving a pair of split molds in the axial direction, when taking out the split mold, a retaining part provided to prevent the rollers from falling off is subjected to plastic deformation, whitening, etc. It will not cause any damage. For this reason, axial draw molding, for example, is due to the large diameter of the roller incorporated in the pocket and the volume of the retaining part being increased, so-called forced removal (the retaining element is elastically expanded to expand the mold element. It is necessary to secure a large volume of the retaining part because it is difficult to take out to the outer diameter side, or the number of rollers incorporated in the pocket is large, the rigidity of the column part becomes low, and the roller easily falls off. Used in some cases. That is, when making such a cage by radial draw molding, even when the volume of the retaining part is increased, the retaining part only turns up, but sufficient retaining cannot be achieved. This is because, according to the axial draw molding, it is not necessary to turn over the retaining portion, so that sufficient retaining can be achieved. Axial draw molding is also used when, for example, it is difficult to take out the mold element to the outer diameter side by arranging the column part radially outside the pitch circle diameter of each roller. ing.

  In any case, in the case of the cage 7a having the above-described configuration, the width of the discontinuous portion 11 can be expanded in the circumferential direction based on elastic deformation of the cage 7a. . For this reason, the width of the discontinuous portion 11 is made larger than the outer diameter of a shaft such as a rotating shaft for assembling the retainer 7a so that the shaft passes between the discontinuous portions 11. The retainer 7a can be assembled around the shaft, or the inner diameter of the retainer 7a can be elastically expanded so that the obstacle can be overcome. It can also be assembled by moving in the axial direction around the shaft.

However, in the case of the cage 7a having the above-described configuration, when the axial dimension of the cage 7a is reduced to be incorporated in a radial roller bearing having a small axial dimension (width dimension), the following is performed. May cause inconvenience.
That is, in the case of the retainer 7a, the axial dimensions and radial dimensions of all the engaging pieces 14a, 14b, 15a, 15b constituting the engaging portion 13 are the same as the shafts of the end portions 12a, 12b. Approximately one half of the directional dimension and the radial dimension. For this reason, the area of the circumferential end surfaces of the engaging pieces 14a, 14b, 15a, 15b is approximately 1/4 of the entire area of the end surfaces 17a, 17b opposed in the circumferential direction across the discontinuous portion 11. It becomes. Moreover, it is formed between the circumferential end surfaces of the engaging pieces 14a, 14b, 15a, 15b and the mating surfaces facing the respective end surfaces in the circumferential direction in the assembled state of the cage 7a. It is difficult to match the size of the gaps created. The reason for this is that restricting the size of all the gaps to be the same requires high injection moldability and mold accuracy, is difficult in production, and causes a significant increase in manufacturing cost.

  For this reason, during operation of the radial roller bearing incorporating the cage 7a, when both end faces 17a, 17b come into contact (collision), any of the engagement pieces 14a, 14b, 15a, 15b There is a possibility that only the circumferential end surface of the engagement piece 14a (14b, 15a, 15b) and its mating surface are in contact with each other, and the contact area is reduced. However, even in such a case, if the axial dimension of the cage 7a is sufficiently large, the contact area can be secured to some extent, so that inconvenience is less likely to occur, but if the axial dimension of the cage 7a is small, It is difficult to secure a sufficient contact area. If a sufficient contact area cannot be ensured in this way, when both end surfaces 17a and 17b contact each other, the both end surfaces 17a and 17b become non-parallel (inclined), and each end As a result of skewing of the rollers held in the vicinity of the portions 12a and 12b, there is a possibility that the inconvenience that the behavior of the cage 7a becomes unstable is caused. Further, there is a possibility that the behavior of the cage 7a becomes unstable due to an increase in the moment load applied to the cage 7a or the elastic deformation of the cage 7a into a non-cylindrical shape. Further, when the skew occurs as described above or stress concentrates on the contact portion when the both end surfaces 17a and 17b contact each other, the cage 7a may be damaged.

British Patent No. 1352909

  In view of the circumstances as described above, the present invention is a radial roller that can be manufactured by so-called axial draw molding, has good assembly workability, and can stabilize the behavior during use even when the axial dimension is small. The invention was invented to realize a bearing cage.

The radial roller bearing retainer of the present invention is integrally formed by injection molding (so-called axial draw molding) of synthetic resin using a mold constituted by a pair of split molds, and is discontinuous at one place in the circumferential direction. And includes a pair of rim portions, a plurality of pillar portions, a plurality of pockets, and an engaging portion.
Of these, the pair of rim portions are each formed in an annular shape, and are provided concentrically with each other at intervals in the axial direction. Further, in the peripheral surfaces of both the rim portions, concave portions that are recessed in the radial direction are formed in portions that are aligned with the respective pockets in the axial direction. Further, the formation positions of these recesses are opposite in the radial direction at both axial portions of the pockets.
Further, the engaging portion engages the end portions provided across the discontinuous portion so that relative displacement in the axial direction and the radial direction is impossible, and one set is provided for each of these end portions. A total of two sets of outer diameter side and inner diameter side engaging pieces are formed. Then, the outer diameter side portion and the inner diameter side portion of the engaging portion respectively engage a pair of outer diameter side engagement pieces and a pair of inner diameter side engagement pieces in the axial direction, and in the axial direction. The outer diameter side engaging pieces and the inner diameter side engaging pieces are engaged in the radial direction by the one side portion and the other axial side portion, respectively.

  Particularly in the case of the radial roller bearing retainer of the present invention, the axial dimension of the pair of outer diameter side engaging pieces and the axial dimension of the pair of inner diameter side engaging pieces are respectively They are different from each other. In addition, in both the outer diameter side portion and the inner diameter side portion of the engagement portion, between the circumferential end surface of the engagement piece having a large axial dimension and the opposing surface facing the end surface in the circumferential direction. The gaps are respectively made smaller than the gaps between the circumferential end surface of the engaging piece having a small axial dimension and the mating surface facing the end surface in the circumferential direction.

Preferably, when carrying out the present invention, for example, as in the invention described in claim 2, the gap between the circumferential end surface of the outer diameter side engagement piece having a large axial dimension and the mating surface, and the axial direction The clearance between the circumferential end surface of the inner diameter side engagement piece having a large dimension and the mating surface is set to the same size.
In this case, preferably, the clearance between the circumferential end surface of the outer diameter side engaging piece having a small axial dimension and the mating surface, and the circumferential end surface of the inner diameter side engaging piece having a small axial dimension and the mating surface. And the same gap between them.

  Further, when the present invention is carried out, preferably, as in the invention described in claim 3, for example, the axial end of the engaging portion is positioned in the axial center rather than the axial side surface (outer surface) of the rim portion. Offset to the side. Thereby, an insertion space is formed in the portion.

According to the radial roller bearing cage of the present invention configured as described above, the assembly workability is good and the behavior during use can be stabilized even when the axial dimension is reduced.
That is, the radial roller bearing retainer of the present invention is made of synthetic resin and has a discontinuous portion at one place in the circumferential direction. Therefore, by elastically deforming the radial roller bearing retainer, The width can be expanded in the circumferential direction. For this reason, even when there are obstacles such as flanges facing outward on the outer peripheral surface of the shaft such as the rotary shaft to which this radial roller bearing retainer is assembled, this radial roller bearing retainer is Can be assembled easily.
In the case of the present invention, the pair of outer diameter side engagement pieces and the pair of inner diameter side engagement pieces have different axial dimensions, and the outer diameter side of the engagement portion. A gap between the circumferential end surface of the engagement piece having a large axial dimension and the mating surface is formed between the circumferential end surface of the engagement piece having a small axial dimension and the mating surface. Each gap is smaller than the gap. For this reason, during operation, when the end faces facing each other across the discontinuous portion abut (collision), the circumferential end face of the engagement piece having a large axial dimension may be brought into contact with the mating face. it can. Therefore, even when the axial dimension of the radial roller bearing retainer is small, a sufficient contact area can be ensured when the both end surfaces are in contact with each other. As a result, it is possible to effectively prevent the behavior of the radial roller bearing retainer from becoming unstable.
Furthermore, the radial roller bearing retainer of the present invention has a shape that allows the pair of split molds to be separated from each other without damaging the retainer after injection molding, including the shapes of the engagement pieces and the rim portions. It is regulated. For this reason, it can be manufactured by so-called axial draw molding, and the manufacturing cost can be kept low.

  Further, according to the invention described in claim 2, when the both end surfaces are in contact with each other, the circumferential end surfaces of the outer diameter side engagement piece and the inner diameter side engagement piece having large axial dimensions are obtained. It can be brought into contact with the mating surface. For this reason, it is possible to secure a larger contact area and sufficiently stabilize the behavior of the radial roller bearing retainer.

  Furthermore, according to the invention described in claim 3, automatic assembly of the radial roller bearing (roller insertion into the pocket) can be performed with the positioning pin inserted in the insertion space. Therefore, the radial roller bearing retainer can be easily positioned in the circumferential direction, and the efficiency of assembly work can be improved. Further, the weight can be reduced by the amount of the space formed, and it is advantageous in terms of preventing sink marks during injection molding.

The perspective view which shows the 1st example of embodiment of this invention. The perspective view shown in the state seen from another direction similarly. The perspective view which shows the 2nd example of embodiment of this invention. The perspective view shown in the state seen from another direction similarly. Sectional drawing of the rotation support part incorporating the radial roller bearing provided with the holder | retainer. The figure which looked at the circumferential direction part of the cage | basket from the radial direction outer side. The perspective view of the radial roller bearing retainer of the conventional structure described in patent document 1. FIG.

[First example of embodiment]
1 and 2 show a first example of an embodiment of the present invention corresponding to claims 1 and 2. The radial roller (needle) bearing retainer 7b of the present example includes a pair of rim portions 8c and 8d that are arranged concentrically at intervals in the axial direction, each having a ring shape, and a circumferential direction. Accordingly, a plurality of column portions 9 and 9 are provided in a state of being intermittently spanned between the two rim portions 8c and 8d. Pockets for holding the respective rollers 6 (see FIG. 5) so that they can freely roll in the portions surrounded by the four sides by the column portions 9 and 9 adjacent to each other in the circumferential direction and the rim portions 8c and 8d. 10 and 10.

  In the case of this example, the retainer 7b is placed in a cavity of a mold (axial draw type) constituted by a pair of split molds (not shown), for example, polyamide resin, polyphenylene sulfide resin, or these After injection molding the same synthetic resin as in the case of a general synthetic resin cage, such as a resin mixed with reinforcing fibers, the two split molds are pulled apart in the axial direction, so-called axial draw molding. Yes.

  For this purpose, a portion of the peripheral surface of each of the rim portions 8c and 8d that is aligned with the pockets 10 and 10 in the axial direction includes a concave portion 16c that is recessed radially inward, and a radially outer portion. Concave portions 16d that are recessed toward each other are alternately formed in the circumferential direction. Further, the concave portions 16c and the concave portions 16d, which are opposite to each other in the radial direction, are disposed on both side portions in the axial direction of the pockets 10 and 10, respectively. Further, the width dimension of each of the recesses 16c and 16d in the circumferential direction is the same as the width dimension of each of the pockets 10 and 10 in the circumferential direction, and the depth dimension in the radial direction is equal to each of the rim portions 8c and 8d. It is 1/2 of the thickness dimension in the radial direction. Such concave portions 16c and 16d allow portions of the split molds provided to form the pockets 10 and 10 to pass in the axial direction when the split molds are moved in the axial direction. Therefore, in the case of the retainer 7b of this example in which such recesses 16a and 16b are formed, the pockets 10 and 10 can be formed by axial draw molding.

  Further, the retainer 7b is provided with a discontinuous portion 11a at one place in the circumferential direction. Then, the end portions 12c and 12d (column portions 9 and 9) provided on both sides of the discontinuous portion 11a are engaged with each other by the engaging portion 13a so that relative displacement in the axial direction and the radial direction is impossible. I am letting. For this purpose, for each of the end portions 12c and 12d, the outer diameter side engaging pieces 14c and 14d and the inner diameter side engaging pieces each having a generally rectangular plate shape (partial cylindrical shape) extending in the circumferential direction. One set of 15c and 15d is formed. Specifically, of the one end portion 12c, the outer diameter side engaging piece 14c is placed on one axial side of the outer diameter side half (the right side in FIG. 1 and the left side in FIG. 2), and the shaft on the inner diameter side half. The inner diameter side engaging pieces 15c are formed on the other side in the direction (left side in FIG. 1, right side in FIG. 2), respectively. Further, of the other end portion 12d, an outer diameter side engagement piece 14d is formed on the other axial side of the outer diameter side half, and an inner diameter side engagement piece 15d is formed on the one axial side of the inner diameter side half. ing. In other words, for each of the end portions 12c and 12d, a pair of convex portions constituted by outer diameter side engaging pieces 14c and 14d and inner diameter side engaging pieces 15c and 15d, and the remaining portion (engaging piece) 14c, 14d, 15c, and 15d) are formed as a pair of recesses.

  Accordingly, even when the engaging pieces 14c, 14d, 15c, and 15d formed in such a positional relationship are moved in the axial direction, the split pieces do not interfere with the split molds. That's it. That is, at the time of injection molding, the split mold on one side, a part of which is disposed on the other axial portion of the outer diameter side engaging piece 14c and the other axial portion of the inner diameter side engaging piece 15d, is injection molded. Later, it is pulled out to the other side in the axial direction. On the other hand, at the time of injection molding, the split mold on the other side, a part of which is arranged on one axial part of the outer diameter side engaging piece 14d and one axial part of the inner diameter side engaging piece 15c, is injected. After molding, it is pulled out to one side in the axial direction. Therefore, when the split molds are moved in the axial direction, the engagement pieces 14c, 14d, 15c, and 15d do not interfere with the split molds.

  In the case of this example, a pair of outer diameter side engaging pieces 14c are formed by the outer diameter side half portion and the inner diameter side half portion of the engaging portion 13a in a state where the cage 7b is incorporated in a radial roller bearing. 14d and the pair of inner diameter side engaging pieces 15c, 15d are respectively engaged in the axial direction, and each outer diameter side engaging piece 14c is similarly formed by the axial half piece and the other axial half portion. , 14d and the inner diameter side engaging pieces 15d, 15c are respectively engaged in the radial direction. Specifically, the axial side surfaces of the pair of outer diameter side engaging pieces 14c and 14d and the pair of inner diameter side engaging pieces 15c and 15d are in contact with each other (or through). Are close to each other). Further, the radially inner side surface of the outer diameter side engaging piece 14c and the radially outer side surface of the inner diameter side engaging piece 15d, and the radially inner side surface of the outer diameter side engaging piece 14d and the inner diameter side engagement The radially outer side surfaces of the pieces 15c are brought into contact with each other (or close to each other). Accordingly, even in the case of this example having such a configuration, relative displacement in the axial direction and the radial direction (and also the twist direction) between the end portions 12c and 12d becomes impossible.

  Particularly in the case of this example, the axial dimension of the pair of outer diameter side engaging pieces 14c, 14d and the axial dimension of the pair of inner diameter side engaging pieces 15c, 15d are mutually different. It is different. Specifically, of the pair of outer diameter side engaging pieces 14c and 14d, the axial dimension of the outer diameter side engaging piece 14c provided at the one end portion 12c is set to the other end portion 12d. It is made larger than the axial direction dimension of the outer diameter side engaging piece 14d provided on the outer side. Further, the axial dimension of the inner diameter side engaging piece 15c provided at the one end portion 12c is set at the other end portion 12d even with respect to the pair of inner diameter side engaging pieces 15c and 15d. The inner diameter side engagement piece 15d is larger than the axial dimension. However, the sum of the axial dimensions of the pair of outer diameter side engaging pieces 14c, 14d and the sum of the axial dimensions of the pair of inner diameter side engaging pieces 15c, 15d are respectively the end portions 12c. , 12d so as to have the same axial dimension. Therefore, in the case of this example, the engagement position (solid line X in FIG. 1) between the outer diameter side engagement pieces 14c and 14d and the inner diameter side engagement pieces 15c and 15d. The engagement position in the axial direction (solid line Y in FIG. 2) is offset in the opposite direction in the axial direction from the axial center position (chain line A in FIGS. 1 and 2) of the retainer 7b (offset). doing). Further, in the case of this example, the axial dimension ratio between the outer diameter side engaging piece 14c and the outer diameter side engaging piece 14d, and the inner diameter side engaging piece 15c and the inner diameter side engaging piece 15d. The axial dimensional ratio is about 3: 2. For this reason, the offset amount with respect to the center position is the same between the engagement position of the both outer diameter side engagement pieces 14c and 14d and the engagement position of the both inner diameter side engagement pieces 15c and 15d.

  Further, the radial dimension of each of the engagement pieces 14c, 14d, 15c, 15d is approximately ½ of the radial dimension of each of the end portions 12c, 12d. For this reason, in the case of this example, the areas of the circumferential end surfaces of the outer diameter side engaging piece 14c and the inner diameter side engaging piece 15c having large axial dimensions face each other across the discontinuous portion 11a. The total area of the end faces 17c and 17d is about 3/10, which can be made larger than the case (1/4) of the cage 7a having the conventional structure.

  In the case of this example, the circumferential end surfaces of the engaging pieces 14c, 14d, 15c, and 15d in a state where the retainer 7b is incorporated, and counterparts that oppose these end surfaces in the circumferential direction, respectively. The size of the gap between the surfaces is regulated as follows. That is, of the pair of outer diameter side engagement pieces 14c and 14d, the circumferential end face of the outer diameter side engagement piece 14c having a large axial dimension, and the opposite face that faces the end face in the circumferential direction The size of the gap α1 between the outer circumferential side end face of the outer diameter side engagement piece 14d having a small axial dimension and the size of the gap β1 between the end face and the mating face facing the end face in the circumferential direction. (Α1 <β1). In addition, of the pair of inner diameter side engagement pieces 15c and 15d, a circumferential end surface of the inner diameter side engagement piece 15c having a large axial dimension and a counter surface facing the end surface in the circumferential direction. The size of the gap γ1 is smaller than the size of the gap δ1 between the circumferential end face of the inner diameter side engaging piece 15d having a small axial dimension and the opposite face in the circumferential direction. (Γ1 <δ1). In the illustrated example, the gap α1 is about 0.7 times the gap β1, and the gap γ1 is about 0.7 times the gap δ1.

Further, in the case of this example, the size of the gap α1 between the circumferential end surface of the outer diameter side engagement piece 14c having a large axial dimension and the mating surface is set to the inner diameter side engagement piece having a large axial dimension. The size of the gap γ1 between the circumferential end face of 15c and the counterpart surface is assumed to be the same (including substantially the same) (α1 = γ1). In addition, the size of the gap β1 between the circumferential end face of the outer diameter side engaging piece 14d having a small axial dimension and the mating face is set to the circumferential end face of the inner diameter side engaging piece 15d having a small axial dimension. The size of the gap δ1 between the contact surface and the mating surface is the same (including substantially the same) (β1 = δ1).
Since the cage 7b of this example is manufactured by axial draw molding as described above, the both ends 12c and 12d are still engaged with each other in the state immediately after the split molds are pulled apart in the axial direction. There is no gap (there is a gap between the end portions 12c and 12d). However, since the cage diameter shrinks in the process of cooling the cage 7b to room temperature, the both end portions 12c and 12d are engaged with each other as shown in the figure, and the engagement pieces 14c, 14d, The sizes of the gaps between the circumferential end surfaces of 15c and 15d and the respective mating surfaces have the relationship as described above. However, in the actual case, the cage 7b may not shrink as desired during the cooling process. However, since the cage 7b is made of synthetic resin and is a highly elastic body, It is copied (elastically deformed) to have a desired shape (a gap relationship is obtained). In addition, the size of the gaps related to the engagement pieces 14d and 15d having a small axial dimension is preferably the same (β1 = δ1) as in the present example. It is not necessary to restrict the size of both gaps to the same. However, the sizes of these gaps are such that the engagement portion 13a is not disengaged by the centrifugal force acting on the cage 7b during operation (the end portions 12c, 12d are not separated from each other). At least one of the radial side engaging piece 14d and the inner diameter side engaging piece 15d can be engaged with an engaging piece adjacent in the axial direction and the radial direction (amount of overlap can be ensured). Set to

According to the cage 7b of this example having the above-described configuration, the assembly workability is good and the behavior during use can be stabilized even when the axial dimension is reduced.
That is, the cage 7b of this example is made of synthetic resin and has the discontinuous portion 11a at one place in the circumferential direction, so that the width of the discontinuous portion 11a can be increased by elastically deforming the cage 7b. Can expand in the circumferential direction. For this reason, even when an obstacle such as an outward flange-shaped flange exists on the outer peripheral surface of a shaft such as a rotating shaft to which the cage 7b is assembled, the cage 7b can be easily assembled around the shaft. Can do.

  In the case of this example, the axial dimension between the pair of outer diameter side engaging pieces 14c and 14d and the pair of inner diameter side engaging pieces 15c and 15d constituting the engaging portion 13a. Are different from each other. And the clearance gap ((alpha) 1, (gamma) 1) between the circumferential direction end surface of the outer diameter side engaging piece 14c and the inner diameter side engaging piece 15c with a large axial direction dimension, and the other surface which opposes these each end surface in the circumferential direction. Of the outer diameter side engaging piece 14d and the inner diameter side engaging piece 15d having a small axial dimension, and a clearance (β1) between the respective opposite end faces in the circumferential direction. , Δ1) are smaller than each other (α1, γ1 <β1, δ1). Furthermore, the size of the clearance between the outer diameter side engaging piece 14c and the inner diameter side engaging piece 15c having a large axial dimension is the same (α1 = γ1). Therefore, when the both end faces 17c and 17d come into contact (collision) with each other during operation, the circumferential end faces of the outer diameter side engagement piece 14c and the inner diameter side engagement piece 15c having large axial dimensions are respectively (In this state, there is a minute gap between the circumferential end surface of the outer diameter side engaging piece 14d and the inner diameter side engaging piece 15d having a small axial dimension and the other surface. Is formed). Therefore, even when the axial dimension of the cage 7b is small, a sufficient contact area can be secured when the both end faces 17c, 17d are in contact with each other (in this example, 3 of the total area of the end faces 17c, 17d). / 5 part). As a result, it is possible to effectively prevent the both end surfaces 17c and 17d from becoming non-parallel (tilted) when the both end surfaces 17c and 17d come into contact with each other. Accordingly, it is possible to prevent skew from occurring in the rollers held in the vicinity of the end portions 12c and 12d, and to effectively prevent the behavior of the cage 7b from becoming unstable. In addition, it is possible to effectively prevent the moment load applied to the cage 7b from becoming large and the cage 7b from being elastically deformed into a non-cylindrical shape. Furthermore, since the skew can be suppressed as described above and the stress concentration can be relaxed by securing a large contact area, it is possible to effectively prevent the cage 7b from being damaged.

  Further, the retainer 7b of this example includes a shape of each of the engagement pieces 14c, 14d, 15c, 15d and the rim portions 8c, 8d, and passes through a pair of split molds in the axial direction, that is, injection molding. The pair of split molds are regulated so as to be separated from each other without damaging the subsequent cage 7b. For this reason, it can be manufactured by so-called axial draw formation, and the manufacturing cost can be kept low.

[Second Example of Embodiment]
3-4 show a second example of an embodiment of the invention corresponding to all claims. In the case of the retainer 7c of this example, both end portions 12e, 12f are engaged with the rim portions 8e, 8f at both ends in the axial direction of the engaging portion 13b for making the relative displacement in the axial direction and the radial direction impossible. These are offset (biased) from the axial side surface (outer surface) to the axial center side. In other words, the engaging portion 13b is provided only in the middle portion in the axial direction excluding both end portions in the axial direction of the cage 7c. For this reason, in the case of this example, the engagement pieces 14e, 14f, 15e, 15f constituting the engagement portion 13b are not formed at the end portions in the axial direction of the end portions 12e, 12f. It is formed in a state offset to the axial center side. In other words, with respect to the structure of the first example of the above-described embodiment, the shape is such that the axial ends of the engagement pieces 14c, 14d, 15c, 15d are cut away. With such a configuration, in the case of this example, the insertion space 18a in which both sides in the axial direction of the engaging portion 13b and the portions on the opposite side to the engaging portion 13b with respect to the axial direction are opened. , 18b, respectively.

  Also in the case of this example, the axial dimension of the pair of outer diameter side engaging pieces 14e, 14f and the axial dimension of the pair of inner diameter side engaging pieces 15e, 15f are the same as the above. As in the case of one example, they are different from each other. In the case of this example, of the pair of outer diameter side engaging pieces 14e, 14f, the axial dimension of the outer diameter side engaging piece 14f provided at the other end 12f is set to the one end 12e. It is made larger than the axial direction dimension of the outer diameter side engaging piece 14e provided in this. On the other hand, of the pair of inner diameter side engaging pieces 15e and 15f, the axial dimension of the inner diameter side engaging piece 15e provided at one end 12e is set to the inner diameter provided at the other end 12f. It is larger than the axial dimension of the side engagement piece 15f. In the case of this example, the sum of the axial dimensions of the pair of outer diameter side engaging pieces 14e, 14f and the sum of the axial dimensions of the pair of inner diameter side engaging pieces 15e, 15f are equal to each other. Each sum is equal to a value obtained by subtracting the sum of the axial dimensions of the insertion spaces 18a and 18b from the axial dimension of the ends 12e and 12f. In this example, the axial dimensional ratio between the outer diameter side engaging piece 14f and the outer diameter side engaging piece 14e and the shaft between the inner diameter side engaging piece 15e and the inner diameter side engaging piece 15f are shown. The directional ratio is about 2: 1.

  Also in the case of this example, of the pair of outer diameter side engagement pieces 14e and 14f, the circumferential end face of the outer diameter side engagement piece 14f having a large axial dimension, and the end face is circumferential. The size of the gap α2 between the opposing surface facing in the direction is set between the circumferential end surface of the outer diameter side engaging piece 14e having a small axial dimension and the opposing surface facing the end surface in the circumferential direction. The gap β2 is smaller than the gap β2 (α2 <β2). In addition, of the pair of inner diameter side engagement pieces 15e and 15f, a circumferential end surface of the inner diameter side engagement piece 15e having a large axial dimension and a counter surface facing the end surface in the circumferential direction. The size of the gap γ2 is smaller than the size of the gap δ2 between the circumferential end face of the inner diameter side engagement piece 15f having a small axial dimension and the opposite face facing the end face in the circumferential direction. (Γ2 <δ2). In the illustrated example, the gap α2 is about 0.7 times the gap β2, and the gap γ2 is about 0.7 times the gap δ2.

  Furthermore, also in the case of this example, the size of the clearance α2 between the circumferential end surface of the outer diameter side engagement piece 14f having a large axial dimension and the counterpart surface is set to the inner diameter side engagement piece having a large axial dimension. The size of the gap γ2 between the circumferential end surface of 15e and the mating surface is the same (including substantially the same) (α2 = γ2). In addition, the size of the gap β2 between the circumferential end face of the outer diameter side engagement piece 14e having a small axial dimension and the mating face is set to the circumferential end face of the inner diameter side engagement piece 15f having a small axial dimension. The size of the gap δ2 between the contact surface and the mating surface is the same (including substantially the same) (β2 = δ2).

In the case of the retainer 7c of the present example provided with the insertion spaces 18a and 18b as described above, each of the insertions is performed when performing automatic assembly of the radial roller bearing (roller insertion work into the pockets 10 and 10). Positioning pins (not shown) can be inserted into the spaces 18a and 18b, respectively. Therefore, by accurately regulating the circumferential position of the positioning pin, the circumferential positions of the pockets 10 and 10 can be made to exactly match the insertion positions of the rollers 6. Therefore, the efficiency of the assembly work of the radial roller bearing can be improved. Further, the cage 7c can be reduced in weight by the amount of the insertion spaces 18a and 18b formed, and it is advantageous from the standpoint of preventing sink marks during injection molding. Of the pair of outer diameter side engagement pieces 14e, 14f, the outer radial side surface of the outer diameter side engagement piece 14f having a large axial dimension is a circle of the cage 7c (pockets 10, 10). It can also be used as a space for marking that is used when regulating the circumferential position.
About another structure and an effect, it is substantially the same as the case of the 1st example of embodiment mentioned above.

  The engagement position between the pair of outer diameter side engagement pieces and the engagement position between the pair of inner diameter side engagement pieces are the center positions in the axial direction of the cage, as in each example of the embodiment described above. Although it may be offset in the opposite direction with respect to the axial direction, it is preferable to offset in the same direction and by the same amount from the aspect of equalizing the volumes of both ends. Moreover, when carrying out the present invention, it is needless to say that a retaining portion may be formed on each column portion in order to prevent the rollers from being detached from each pocket. Further, the insertion space for inserting the positioning pin is not limited to the case where it is formed on both sides in the axial direction of the engaging portion, and can be formed only on one side.

DESCRIPTION OF SYMBOLS 1 Radial roller bearing 2 Outer diameter side member 3 Outer ring raceway 4 Axis 5 Inner ring raceway 6 Roller 7, 7a-7c Cage 8, 8a-8f Rim part 9 Column part 10 Pocket 11, 11a Discontinuous part 12a-12f End part 13 , 13a, 13b Engaging portion 14a-14f Outer diameter side engaging piece 15a-15f Inner diameter side engaging piece 16a-16d Recessed portion 17a-17d End face 18a, 18b Insertion space

Claims (3)

It is made integrally by injection molding of synthetic resin using a mold composed of a pair of split molds, and has a discontinuous portion at one place in the circumferential direction.
A pair of rim portions, a plurality of pillar portions, a plurality of pockets, and an engaging portion;
Each of the pair of rim portions is an annular shape, and is provided concentrically with a gap in the axial direction. Of the peripheral surfaces of both rim portions, the pockets and the pockets are arranged in the axial direction. The matching portions are each formed with a concave portion that is recessed in the radial direction, and the positions where these concave portions are formed are opposite in the radial direction at both axial portions of the pockets,
Each of the column portions is provided in a state of being spanned between the rim portions intermittently over the circumferential direction,
Each of the pockets is provided in a portion surrounded by the four rims by the two rim portions and a column portion adjacent in the circumferential direction.
The engaging portion engages the relative displacement in the axial direction and the radial direction between the end portions provided across the discontinuous portion, and the outer diameter of one end portion of these both end portions. An outer diameter side engagement piece provided in a state extending in the circumferential direction on the one side portion in the axial direction of the side portion and a state extending in the circumferential direction on the other side portion in the axial direction of the inner diameter side portion. An inner diameter side engaging piece, an outer diameter side engaging piece provided in a circumferentially extending state on the other axial side portion of the outer diameter side portion of the other end portion, and an axially one side of the inner diameter side portion. An inner diameter side engaging piece provided in a state extending in a circumferential direction at the portion, and a pair of outer diameter side engaging pieces between the outer diameter side portion and the inner diameter side portion of the engaging portion, and A pair of inner diameter side engaging pieces are engaged with each other in the axial direction, and each outer diameter side engagement is similarly performed between the one axial side portion and the other axial side portion. Those formed by respectively engaged in the radial direction and each of the inner diameter side engagement piece and,
In radial roller bearing cages,
The pair of outer diameter side engagement pieces and the pair of inner diameter side engagement pieces have different axial dimensions, and the outer diameter side portion and the inner diameter side portion of the engagement portion. The gap between the circumferential end surface of the engagement piece having a large axial dimension and the opposing surface facing the end surface in the circumferential direction is the circumferential direction of the engagement piece having a small axial dimension. A radial roller bearing retainer, characterized in that it is smaller than the gap between the end face and the opposite face facing the end face in the circumferential direction.   Of the pair of outer diameter side engagement pieces, a gap between the circumferential end surface of the outer diameter side engagement piece having a large axial dimension and the opposing surface facing the end surface in the circumferential direction, and a pair of The clearance between the circumferential end surface of the inner diameter side engagement piece having a large axial dimension among the inner diameter side engagement pieces and the opposing surface facing the end surface in the circumferential direction is the same size. The radial roller bearing retainer described in 1.   The insertion space is formed in the said part by offsetting the axial direction edge part of an engaging part to the axial direction center side rather than the axial direction side surface of a rim | limb part. The radial roller bearing retainer described in the section.

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