Cage for deep groove ball bearings, and method for manufacturing the same.

Abstract

Even with a large number of balls, the ability to prevent the crown-shaped cage from detaching axially from the bearing is enhanced, and a low-cost deep groove ball bearing cage is provided that is easy to demold, has excellent moldability, and is low cost. [Solution] The multiple pockets include multiple first pockets that prevent the cage for the deep groove ball bearing from falling out of the bearing axially, and each first pocket has a cylindrical inner surface and claws that narrow the distance between a pair of adjacent columnar portions at the end opposite the annular portion, and at least two first pockets arranged adjacent to each other in the circumferential direction constitute a group of first pockets, and the central axes of the inner surfaces of the first pockets constituting one group of first pockets are parallel to each other.

Description

Technical Field

[0001] The present invention relates to a cage for a deep groove ball bearing and a method for manufacturing the same.

Background Art

[0002] Deep groove ball bearings are widely used to support the rotating parts of various rotating machines. In a deep groove ball bearing, a plurality of balls are held in a rolling state at equal intervals in the circumferential direction between an outer ring and an inner ring by a crown-shaped cage.

[0003] A general crown-shaped cage includes an annular portion and a plurality of column portions protruding axially on one side at a predetermined interval in the circumferential direction of the annular portion. A plurality of pockets for holding balls are formed by the annular portion and a pair of adjacent column portions in the circumferential direction. The inner surfaces of the plurality of pockets for holding balls have a spherical shape. Further, in order to prevent the crown-shaped cage from axially dropping out between the outer ring and the inner ring, elastic claws are provided on the plurality of column portions.

[0004] Generally, a crown-shaped cage is manufactured by injection molding of a synthetic resin. In order to manufacture a resin cage at low cost, an injection molding method called an axial draw method is used. In the injection molding of the axial draw method, in the process of removing the product from the mold, that is, the demolding process, the crown-shaped cage is axially demolded with respect to the mold. At this time, the crown-shaped cage is axially pushed by a pin or the like, so that the claws provided on the column portions are elastically deformed and removed from the mold.

[0005] When increasing the number of balls in the bearing for the purpose of improving the load capacity of the bearing or the like, the circumferential thickness of the column portion becomes small in the crown-shaped cage. As a result, when demolding, the claws and the column portions may not withstand elastic deformation, and molding defects may occur.

[0006] The retainers described in Patent Documents 1 and 2 include both a pocket having claws that hold the balls in the axial direction and a spherical inner surface, and a pocket that does not have claws that hold the balls in the axial direction and has a cylindrical inner surface that extends in the axial direction. These retainers all share the common aim of allowing axial demolding during molding while still providing the function of the balls holding the retainer in the axial direction, by limiting the number of pockets with claws that would be problematic during demolding. [Prior art documents] [Patent Documents]

[0007] [Patent Document 1] Utility Model Registration No. 3122529 Gazette [Patent Document 2] International Publication No. 2019 / 198762 [Overview of the Initiative] [Problems that the invention aims to solve]

[0008] However, when improving the axial fall prevention performance of the crown-shaped retainer, it can be difficult to limit the number of pockets with claws, as is the case with the retainers described in Patent Documents 1 and 2.

[0009] Furthermore, the cages described in Patent Documents 1 and 2 are configured for low-cost axial-draw injection molding. That is, these cages undergo a process in which, during demolding of the spherical pocket, the claws provided on the column are elastically deformed, and the cage is pulled axially out of the mold. This process causes the cage to whiten due to deformation, resulting in molding defects. In the future, as bearings with even higher load capacities are required and the number of balls is increased, the shape and size of the claws and column will be further restricted, and it is anticipated that moldability will deteriorate.

[0010] The present invention has been made in view of the above problems, and its purpose is to provide a deep groove ball bearing cage that can improve the performance of preventing the crown-shaped cage from falling out of the bearing axially even when there are many balls, is easy to demold, has excellent moldability, and is low cost, as well as a method for manufacturing the same. [Means for solving the problem]

[0011] The above objective of the present invention is achieved by the following configuration. (1) The annular part and, Multiple columnar portions protruding axially from the annular portion, The ring portion and the pair of columnar portions adjacent to each other in the circumferential direction form a plurality of pockets that hold a plurality of balls, A resin cage for deep groove ball bearings, comprising: The plurality of pockets include a plurality of first pockets that prevent the cage for the deep groove ball bearing from falling out of the bearing in the axial direction, The aforementioned first pocket is The cylindrical inner surface and A claw portion that narrows the distance between a pair of adjacent column portions at the end opposite to the annular portion, Equipped with, Multiple first pockets arranged adjacent to each other in the circumferential direction constitute a first pocket group. The central axes of the inner surfaces of the first pockets that constitute one of the first pocket groups are parallel to each other. A cage for deep groove ball bearings, characterized by the following features. (2) A method for manufacturing a cage for a deep groove ball bearing as described in (1), The first pocket is injection molded using a radial draw method. A method for manufacturing a cage for deep groove ball bearings, characterized by the following features. [Effects of the Invention]

[0012] According to the present invention, even when the number of balls is large, it is possible to enhance the performance of preventing the crown-shaped cage from axially dropping off from the bearing, and to provide a cage for a deep groove ball bearing that is easy to release from the mold, has excellent moldability, and is low in cost, and a method for manufacturing the same.

Brief Description of the Drawings

[0013] [Figure 1] FIG. 1 is a cross-sectional view of a deep groove ball bearing provided with a cage for a deep groove ball bearing according to an embodiment of the present invention. [Figure 2] FIG. 2 is a perspective view of a cage for a deep groove ball bearing according to an embodiment of the present invention. [Figure 3] FIG. 3 is a partially enlarged view of FIG. 2. [Figure 4] FIG. 4 is a top view of a cage for a deep groove ball bearing according to an embodiment of the present invention. [Figure 5] FIG. 5 is a top view of a cage for a deep groove ball bearing according to Modification 1 of an embodiment of the present invention. [Figure 6] FIG. 6 is a top view of a cage for a deep groove ball bearing according to Modification 2 of an embodiment of the present invention.

Embodiments for Carrying Out the Invention

[0014] Hereinafter, embodiments according to the present invention will be described based on the accompanying drawings. FIG. 1 is a cross-sectional view of a deep groove ball bearing provided with a cage for a deep groove ball bearing according to an embodiment of the present invention. FIG. 2 is a perspective view of a cage for a deep groove ball bearing according to an embodiment of the present invention. FIG. 3 is a partially enlarged view of FIG. 2. FIG. 4 is a top view of a cage for a deep groove ball bearing according to an embodiment of the present invention.

[0015] As shown in FIG. 1, the cage 10 for a deep groove ball bearing according to the present embodiment is incorporated into, for example, a deep groove ball bearing 100. The deep groove ball bearing 100 includes an outer ring 111 having a raceway surface 111a on its inner peripheral surface, an inner ring 112 having a raceway surface 112a on its outer peripheral surface, a plurality of balls 113 disposed between the raceway surfaces 111a and 112a of the outer ring 111 and the inner ring 112, and a cage 10 for a deep groove ball bearing that holds the balls 113 rotatably. Hereinafter, the cage 10 for a deep groove ball bearing may be simply referred to as the cage 10. Also, the deep groove ball bearing 100 may be simply referred to as the bearing 100.

[0016] As shown in FIGS. 1 and 2, the cage 10 according to the present embodiment includes an annular portion 11, a plurality of column portions 12 protruding from the annular portion 11 to one side in the axial direction, and a plurality of pockets 50 formed by the annular portion 11 and a pair of column portions 12 adjacent in the circumferential direction, which hold a plurality of balls 113. In the present embodiment, in terms of the axial direction, the direction in which the plurality of column portions 12 protrude from the annular portion 11 (the upper side in FIG. 2) is referred to as one side in the axial direction, and the opposite side to one side in the axial direction (the lower side in FIG. 2) is referred to as the other side in the axial direction. Note that FIG. 4 is a plan view of the cage for a deep groove ball bearing according to the embodiment of the present invention as viewed from one side in the axial direction.

[0017] As shown in FIGS. 2 to 4, in the present embodiment, the plurality of pockets 50 include a plurality of first pockets 51 provided with claw portions 21 for preventing the cage 10 from axially dropping off from the bearing 100, and a plurality of second pockets 52 not provided with means for the cage 10 to axially drop off from the bearing 100. The first pocket 51 restricts the axial movement of the cage 10 when the claw portion 21 catches on the ball 113. The cage 10 according to the present embodiment is provided with 23 pockets 50. Among the 23 pockets 50, 8 are the first pockets 51 and 15 are the second pockets 52.

[0018] In this embodiment, two first pockets 51 are arranged adjacent to each other in the circumferential direction, and the two circumferentially adjacent first pockets 51 constitute a first pocket group 61. As described later, the two first pockets 51 that constitute one first pocket group 61 have central axes parallel to each other on the inner surface 20 of the cylindrical first pocket 51. In this embodiment, eight first pockets 51 constitute four first pocket groups 61. The total number of pockets 50, the number of first pockets 51, and the number of second pockets 52 can be changed. Each first pocket group 61 may consist of multiple first pockets 51 that are adjacent to each other in the circumferential direction, and the number of first pockets 51 that constitute a first pocket group 61 is not particularly limited as long as there are multiple first pockets 51. For example, a first pocket group 61 may consist of three or more first pockets 51 that are arranged adjacent to each other in the circumferential direction. Also, the number of first pockets 51 that constitute a first pocket group 61 may differ for each first pocket group 61.

[0019] Furthermore, between adjacent first pocket groups 61 in the circumferential direction, three or four second pockets 52 are arranged adjacently in the circumferential direction. As a result, the four first pocket groups 61, each consisting of two first pockets 51, are arranged at approximately equal intervals in the circumferential direction. Here, "approximately equal intervals" means that when M is the number of second pockets 52 arranged between any two adjacent first pocket groups 61, and N is the number of second pockets 52 arranged between any other two adjacent first pocket groups 61, the difference between M and N for any combination is always 2 or less. In the illustrated example, the number of second pockets 52 arranged between two adjacent first pocket groups 61 in the circumferential direction is 3 or 4, and M and N are 3 or 4, respectively. That is, the difference between M and N is 1 for at least one pair, and in any combination of M and N, the difference between M and N is 2 or less. Note that the first pocket groups 61 only need to consist of at least three first pocket groups 61 arranged at approximately equal intervals in the circumferential direction. As a result, the retainer 10 is supported evenly in the circumferential direction by the first group of pockets 61, which prevents it from falling out in the axial direction, and the posture of the retainer 10 is stabilized. Furthermore, as will be described later, the retainer 10 does not necessarily have to have a second pocket 52.

[0020] Here, we will describe the column portion 12. As shown in Figures 2 and 3, the column portion 12 separates two adjacent pockets 50 in the circumferential direction. More specifically, the column portion 12 includes a first column portion 12a that separates two adjacent first pockets 51 in the circumferential direction, a second column portion 12b that separates the adjacent first pockets 51 and second pockets 52 in the circumferential direction, and a third column portion 12c that separates two adjacent second pockets 52 in the circumferential direction. The first column portion 12a has two claw portions 21 extending in both directions in the circumferential direction at the tip of its circumferential side surface. The second column portion 12b has claw portions 21 at the tip of its circumferential side surface facing the first pocket 51, but does not have claw portions 21 on the circumferential side surface facing the second pocket 52. The third column portion 12c does not have claw portions 21. In this embodiment, the first column portion 12a and the second column portion 12b, which are adjacent in the circumferential direction, constitute the first pocket 51, and the second column portion 12b and the third column portion 12c, which are adjacent in the circumferential direction, or two third column portions 12c, which are adjacent in the circumferential direction, constitute the second pocket 52. The second column portion 12b is located at both ends in the circumferential direction of the column portion 12 that constitute the first pocket group 61. As shown in the modified example described later, if the number of first pockets 51 constituting one first pocket group 61 is three or more, two first column portions 12a, which are adjacent in the circumferential direction, may constitute the first pocket 51. In this embodiment, the tip surfaces of the first column portion 12a, the second column portion 12b, and the third column portion 12c are located in the same axial position and are all formed flat over the circumferential direction.

[0021] The second pocket 52 is positioned between adjacent first pocket groups 61 in the circumferential direction and has the same cross-sectional shape along the axial direction. That is, the second pocket 52 is formed between the wall surfaces 33, which are the circumferential sides of a pair of adjacent columnar portions 12 (adjacent second columnar portions 12b and third columnar portions 12c, or two adjacent third columnar portions 12c). In this embodiment, the wall surface 33 of the columnar portion 12 defining the second pocket 52 is a plane extending in the radial and axial directions, and the cross-sectional shape of the second pocket 52 perpendicular to the axial direction remains constant regardless of its axial position. Furthermore, the other axial side of the second pocket 52 is defined by the end face on one axial side of the annular portion 11, and the one axial side of the second pocket 52 has an opening. In this embodiment, the circumferential width W2 of the second pocket is larger than the diameter of the ball 113. That is, the second pocket 52 has the function of maintaining the circumferential spacing between the balls 113, but does not have the function of holding the balls 113 in the radial and axial directions.

[0022] The first pocket 51 has a cylindrical inner surface 20 and is equipped with a claw portion 21 at the end opposite the annular portion 11 that narrows the distance between a pair of adjacent column portions 12. Here, in the first column portion 12a and the second column portion 12b which are adjacent in the circumferential direction and constitute the first pocket 51, the claw portion 21 protrudes from the tips of the first column portion 12a and the second column portion 12b so as to move closer to each other. The inner surface 20 is formed into a cylindrical surface such that the central axes O1 and O2 are perpendicular to the axial direction by the smooth connection of the end face on one axial side of the annular portion 11, the opposing circumferential sides of the circumferentially adjacent first column portion 12a and the second column portion 12b and the claw portion 21. That is, an opening is formed on one axial side of the first pocket 51 by a part of the circumferential direction of the cylindrical surface of the inner surface 20 being missing. The cross-sectional shape of the first pocket 51 perpendicular to the central axes O1 and O2 remains constant regardless of the axial position.

[0023] Furthermore, as shown in Figure 3, the circumferential width W1 between the tips of the pair of opposing claw portions 21 is smaller than the diameter of the ball 113. Therefore, the ball 113 placed in the first pocket 51 and the claw portion 21 catch on each other, preventing the retainer 10 from falling out of the bearing 100 in the axial direction.

[0024] As shown in Figures 2 to 4, the central axes O1 and O2 of the inner surfaces 20 of the two first pockets 51 that constitute one first pocket group 61 are parallel to each other. Furthermore, the central axes O1 and O2 are parallel to the straight line CR that connects the circumferential center R of the first pocket group 61 and the center point C of the retainer 10. Here, the circumferential center R of the first pocket group 61 is the circumferential center of the region between the two second column portions 12b located at both ends in the circumferential direction of the column portion 12 that defines the first pocket group 61, and in this embodiment it coincides with the circumferential center of the first column portion 12a. The center point C is a point on the central axis P of the retainer 10 and is a point on the same plane as the central axes O1 and O2 of the inner surface 20. The straight line CR is on the same plane as the central axes O1 and O2 of the inner surface 20 and is also a straight line that points in the radial direction.

[0025] Here, the retainer 10 is made of a resin material and is integrally molded by injection molding. Two injection molding methods are known for use in resin retainers: the axial draw method and the radial draw method. In axial draw injection molding, the retainer is released from the mold axially during the process of removing the product from the mold, i.e., the demolding process. On the other hand, in radial draw injection molding, the retainer is released from the mold radially. Generally, in the manufacture of crown-type retainers, axial draw injection molding requires fewer steps and is less expensive than radial draw injection molding.

[0026] In this embodiment, the first pocket 51 is injection molded by a radial draw method, and the second pocket 52 is injection molded by an axial draw method. The retainer 10 according to this embodiment is injection molded by combining an axial draw mold using axially movable mold parts and a radial draw mold using the same number of radially movable mold parts as the first pocket group 61. After integrally molding the retainer 10, when demolding, the mold parts that are mainly in contact with the inner surface 20 of the first pockets 51 that constitute the first pocket group 61 are removed radially from the retainer 10, and then the remaining axially movable mold parts are removed axially from the retainer 10. In the example of Figure 4, four first pocket groups 61 are molded using four radially movable mold parts. That is, the four mold parts are removed in the direction of arrows IV, IV', IV'', and IV'''', which are in the linear CR direction.

[0027] As described above, by making the central axes O1, O2 of the first pockets 51 constituting the first pocket group 61 parallel to the straight line CR, a common mold part that moves radially can be used for multiple first pockets 51 constituting one first pocket group 61. This reduces the number of radially movable mold parts used in radial draw injection molding, and while reducing man-hours and costs, it is possible to increase the number of first pockets 51 that hold the ball 113 in the axial direction.

[0028] Furthermore, for the two first pockets 51 located at both circumferential ends of the first pocket group 61, if points A and B are the positions that are the radial centers of the first pockets 51 on the central axes O1 and O2 of the inner surface 20, it is preferable that the angle θ1 formed by the straight lines AC and CR connecting point A and center point C, and the angle θ2 formed by the straight lines BC and CR connecting point B and center point C, are small. This ensures that even for the first pockets 51 located at both circumferential ends of the first pocket group 61, the gap of the first pocket 51 is secured while ensuring the engagement between the claw portion 21 and the ball 113, thereby ensuring the retention performance of the retainer 10 and enabling the smooth rolling of the ball 113. In order to reduce angles θ1 and θ2, it is preferable that the number of balls be 20 or more, and that the number of first pockets 51 constituting one first pocket group 61 be about two or three.

[0029] As described above, in the cage 10 according to this embodiment, a plurality of first pockets 51 are arranged adjacent to each other in the circumferential direction to prevent the first pockets 51 from falling out of the bearing 100 in the axial direction, forming a first pocket group 61. By making the central axes O1, O2 of the first pockets 51 that make up the first pocket group 61 parallel to the straight line CR, even when there are many balls, the performance of preventing the cage 10 from falling out of the bearing 100 in the axial direction can be improved, and a cage for deep groove ball bearings that is easy to demold, has excellent moldability, and is low cost, as well as a method for manufacturing the same, can be provided.

[0030] The following describes modifications of this embodiment. Figure 5 is a top view of a cage for a deep groove ball bearing according to Modification 1 of the embodiment of the present invention. Figure 6 is a top view of a cage for a deep groove ball bearing according to Modification 2 of the embodiment of the present invention.

[0031] As shown in Figure 5, the holder 10 according to Modification 1 is provided with 24 pockets 50. Of the 24 pockets 50, 9 are first pockets 51 and 15 are second pockets 52. In the holder 10 of this modification, three circumferentially adjacent first pockets 51 constitute one first pocket group 61. That is, the nine first pockets 51 constitute three first pocket groups 61. In addition, five second pockets 52 are arranged circumferentially adjacent between the circumferentially adjacent first pocket groups 61, and the three first pocket groups 61 are arranged at equal intervals in the circumferential direction.

[0032] In this modified example, the first column portion 12a and the second column portion 12b, or two first column portions 12a adjacent in the circumferential direction, constitute the first pocket 51, and the second column portion 12b and the third column portion 12c, or two third column portions 12c adjacent in the circumferential direction, constitute the second pocket 52.

[0033] Furthermore, the central axes O1, O2, and O3 of the inner surfaces 20 of the three first pockets 51 that constitute one first pocket group 61 are parallel to each other. The straight line CR connecting the circumferential center R of the first pocket group 61 and the center point C coincides with the central axis O2 of the first pocket 51 located in the circumferential center of the three first pockets 51. The three first pocket groups 61 are injection molded using mold parts that are movable in the direction of arrows V, V', and V'', which are in the direction of the straight line CR.

[0034] In this modified example, the wall surfaces 33 of a pair of circumferentially adjacent columnar sections 12 (a second columnar section 12b and a third columnar section 12c, or two third columnar sections 12c, adjacent in the circumferential direction) that define the second pocket 52 are a pair of cylindrical surfaces whose central axis extends in the axial direction. Therefore, the cross-sectional shape perpendicular to the axial direction of the pair of wall surfaces 33 constituting the second pocket 52 remains constant regardless of the axial position. As a result, the second pocket 52 can hold the ball 113 in the radial direction.

[0035] As shown in Figure 6, the holder 10 according to Modification 2 is provided with six pockets 50, all of which are first pockets 51. Since the holder 10 according to Modification 2 does not have second pockets 52, all first pockets 51 are arranged to be adjacent to each other in the circumferential direction, but two circumferentially adjacent first pockets 51 constitute one first pocket group 61. In other words, the six first pockets 51 constitute three first pocket groups 61.

[0036] In this example, all column portions 12 are first column portions 12a, and each has two claw portions 21 extending in the circumferential direction at the tip of its circumferential side surface. The circumferential center portion R of the first pocket group 61 coincides with the circumferential center portion of the first column portion 12a.

[0037] The present invention can also be applied when the number of balls is small, as in Modification 2, or when the holder 10 does not have a second pocket 52.

[0038] It should be noted that the present invention is not limited to the embodiments illustrated above, and can be modified as appropriate without departing from the spirit of the invention.

[0039] As described above, the following matters are disclosed in this specification: (1) The annular part and, Multiple columnar portions protruding axially from the annular portion, The ring portion and the pair of columnar portions adjacent to each other in the circumferential direction form a plurality of pockets that hold a plurality of balls, A resin cage for deep groove ball bearings, comprising: The plurality of pockets include a plurality of first pockets that prevent the cage for the deep groove ball bearing from falling out of the bearing in the axial direction, The aforementioned first pocket is The cylindrical inner surface and A claw portion that narrows the distance between a pair of adjacent column portions at the end opposite to the annular portion, Equipped with, Multiple first pockets arranged adjacent to each other in the circumferential direction constitute a first pocket group. The central axes of the inner surfaces of the first pockets that constitute one of the first pocket groups are parallel to each other. A cage for deep groove ball bearings, characterized by the following features. This configuration enhances the ability to prevent the crown-shaped cage from detaching axially from the bearing, even when there are many balls. It also provides a low-cost cage for deep groove ball bearings that is easy to demold and has excellent moldability.

[0040] (2) The central axis of the inner surface of the first pocket that constitutes the first pocket group is parallel to the straight line connecting the circumferential center of the first pocket group and the center of the deep groove ball bearing cage. A cage for a deep groove ball bearing as described in (1), characterized in that it is a cage for a deep groove ball bearing as described in (1). This configuration makes it easier to ensure a wide spacing between adjacent columnar sections in the circumferential direction that constitute the first pocket, thereby preventing the rolling of the ball from being hindered by the columnar sections.

[0041] (3) Having at least three of the first pocket groups, The first group of pockets is arranged at approximately equal intervals in the circumferential direction. A cage for a deep groove ball bearing according to (1) or (2), characterized in that it is a cage for a deep groove ball bearing according to (1) or (2). With this configuration, by arranging the first group of pockets at equal intervals in the circumferential direction, the cage for the deep groove ball bearing is supported in a balanced manner in the circumferential direction, resulting in a stable posture.

[0042] (4) The plurality of pockets include a plurality of second pockets that are arranged between the first groups of pockets that are adjacent in the circumferential direction and have the same cross-sectional shape along the axial direction. A cage for a deep groove ball bearing, characterized by any one of (1) to (3). This configuration allows for the provision of a deep groove ball bearing cage with an increased number of balls at a low cost, by including a second pocket that is injection-molded using an axial draw method, along with a first pocket that is injection-molded using a radial draw method.

[0043] (5) A method for manufacturing a cage for a deep groove ball bearing as described in any one of (1) to (4), The first pocket is injection molded using a radial draw method. A method for manufacturing a cage for deep groove ball bearings, characterized by the following features. This configuration allows injection molding to be performed without elastically deforming the claw portion that holds the ball in the axial direction, thereby improving moldability.

[0044] (6) A method for manufacturing a cage for a deep groove ball bearing as described in (4), The first pocket is injection molded using a radial draw method. The second pocket is injection molded using an axial draw method. A method for manufacturing a cage for deep groove ball bearings, characterized by the following features. This configuration enhances the ability to prevent the crown-shaped cage from detaching axially from the bearing, even when there are many balls. It also provides a low-cost manufacturing method for deep groove ball bearing cages that is easy to demold and has excellent moldability. [Explanation of Symbols]

[0045] 10 Cage for deep groove ball bearings (cage) 11 Circular section 12 Pillar section 12a First pillar part 12b Second pillar part 12c Third pillar part 20 Inner self 21 Nail area 33 Wall surface 50 pockets 51 First Pocket 52 Second Pocket 61 First Pocket Group 100 Deep groove ball bearings 111 Outer ring 111a Raceway surface 112 Inner Ring 112a Raceway surface 113 balls O1,O2,O3 center axis W1,W2 Circumferential width

Claims

1. The annular part, Multiple columnar portions protruding axially from the annular portion, The ring portion and the pair of columnar portions adjacent to each other in the circumferential direction form a plurality of pockets that hold a plurality of balls, A resin cage for deep groove ball bearings, comprising: The plurality of pockets include a plurality of first pockets that prevent the cage for the deep groove ball bearing from falling out of the bearing in the axial direction, The aforementioned first pocket is The cylindrical inner surface and A claw portion that narrows the distance between a pair of adjacent column portions at the end opposite to the annular portion, Equipped with, Multiple first pockets arranged adjacent to each other in the circumferential direction constitute a first pocket group. The central axes of the inner surfaces of the first pockets that constitute one of the first pocket groups are parallel to each other. A cage for deep groove ball bearings, characterized by the following features.

2. The central axis of the inner surface of the first pocket that constitutes the first pocket group is parallel to the straight line connecting the circumferential center of the first pocket group and the center of the deep groove ball bearing cage. A cage for a deep groove ball bearing according to claim 1, characterized in that...

3. Having at least three of the first pocket groups, The first group of pockets is arranged at approximately equal intervals in the circumferential direction. A cage for a deep groove ball bearing according to claim 1 or 2, characterized in that...

4. The aforementioned plurality of pockets include a plurality of second pockets arranged between the first groups of pockets that are adjacent in the circumferential direction and have the same cross-sectional shape along the axial direction. A cage for a deep groove ball bearing according to claim 3, characterized in that...

5. A method for manufacturing a cage for a deep groove ball bearing according to claim 3, The first pocket is injection molded using a radial draw method. A method for manufacturing a cage for deep groove ball bearings, characterized by the following features.

6. A method for manufacturing a cage for a deep groove ball bearing according to claim 4, The first pocket is injection molded using a radial draw method. The second pocket is injection molded using an axial draw method. A method for manufacturing a cage for deep groove ball bearings, characterized by the following features.

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