JP2007056893A - Ball bearing cage - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a crowned synthetic resin cage 8 for rollingly holding a plurality of balls 6 constituting a ball bearing 1, having simple and inexpensive construction for reducing the torque of the ball bearing 1 while suppressing the radially outward deformation of ball holding pawls 12 constituting pockets 10. <P>SOLUTION: The cage 8 comprises a crowned synthetic resin cage body 19 opened at one axial end and formed in circumferentially almost equal distribution, and having the plurality of pockets 10 in which the balls 6 are fitted and held by the pair of ball holding pawls 12 protruded to the side of an opening portion, a plurality of connection members 14 provided between the adjacent pockets 10 and protruded to one axial end, and an annular rod material 18 bridged between the connection members 14 for suppressing the radially outward deformation of the ball holding pawls 12. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a crown type synthetic resin retainer for ball bearings that holds a plurality of balls constituting a ball bearing in a freely rolling manner, and is used, for example, in a rotational movement portion of an automobile or various power units.

  Conventionally, as a cage used for a ball bearing, there are a crown type cage, a machined cage, a corrugated press cage and the like. The crown-type cage has characteristics such as self-lubricity, low friction characteristics, light weight, corrosion resistance, and low noise as compared with the corrugated press cage. For this reason, the crown type cage is often used particularly in a high-speed rotation environment.

  Based on FIG.10, 11, the structure of the conventional crown type | mold retainer is demonstrated easily. The crown-shaped cage 103 is inserted between the outer ring 101 and the inner ring 102 of the rolling bearing 100, and holds the balls 104 so that they can roll at equal intervals. Seal members 105 are provided at both ends in the axial direction between the outer ring 101 and the inner ring 102.

  The crown-shaped cage 103 is obtained by molding a synthetic resin material, and is formed by opening pockets 111 for fitting and holding the balls 104 to one end side in the axial direction at several locations on the annular base 110 that are substantially equidistant around the circumference. Has been.

  And in the annular | circular base 110, the nail | claw 113 for the ball holding | maintenance which protrudes toward the opening part side of the pocket 111 is provided in the front-end | tip part of the partition protrusion piece 112 which exists between the pockets 111 adjacent in the circumferential direction. Yes. The ball holding claw 113 is designed to be elastically deformable so that the ball 104 can be easily inserted and removed when the ball 104 is assembled into the pocket 111 from the axial direction.

In this manner, by providing the ball holding claws 113 on both sides in the circumferential direction on the free end side of each partition projection piece 112, a recess 114 is formed between them. The grease is supplied to the pocket 111 by using it as a part.
Japanese Examined Patent Publication No. 47-21645 Japanese Utility Model Publication No. 6-1848

  In such a synthetic resin crown-shaped cage 103, the distal end portion of the ball holding claw 113, which is a free end, is deformed radially outward by centrifugal force during high-speed rotation, and the radially inner side is the ball 104. There is a problem that the gap is clogged due to interference with torque and torque loss increases.

  Therefore, conventionally, proposals have been made to prevent the cage from being deformed. For example, in Patent Document 1, in a staggered or comb-shaped flat roller cage, a steel wire ring is attached along a circumferential groove formed on a side edge, and the configuration as a cage is maintained. Is disclosed. However, Patent Document 1 relates to prevention of deformation of the roller cage, and does not describe prevention of deformation of the crown type cage for ball bearings.

  Patent Document 2 discloses a configuration for preventing deformation in a crown type cage for a ball bearing by connecting connecting legs protruding between pockets with a lid.

  However, in the case of the configuration of Patent Document 2, a dedicated lid for connecting the connecting legs is separately required, and the cover has a complicated structure in the connection structure with the connecting legs, and so on. There was a problem of high costs. In addition, the installation of a lid having a thickness in the radial direction prevents grease from being lubricated in the pocket, especially in the case of grease lubrication. Especially in ball bearings used at high speed rotation, May cause problems such as burn-in.

  The cage for ball bearings of the present invention includes a plurality of ball-holding claws that are formed in a substantially equal circumference and opened toward one end side in the axial direction, and are inserted and held by a pair of ball-holding claws protruding toward the opening side. A cage-type synthetic resin retainer body with pockets, a plurality of connecting members projecting on one end in the axial direction between adjacent pockets, and spanning between the connecting members. And an annular wire rod that suppresses deformation in the direction.

  As the ball bearing to which the cage of the present invention is applied, a medium-sized or large-sized thin-walled deep groove ball bearing is preferably exemplified, and as an example, it is applied to a ball bearing having an inner diameter of 100 mm or more.

  The connecting member may be formed between each adjacent pocket, or may be formed intermittently between adjacent pockets.

  The connecting member is formed in a prismatic shape, a cylindrical shape, or the like, and is integrally formed with the cage body. Alternatively, separate members may be connected by welding or the like.

  The radial width dimension of the connecting member is formed to be smaller than the radial width dimension of the cage main body, and is projected on the inner side in the radial direction of the cage main body. It is preferable that contact can be avoided. Alternatively, the radial width dimension of the connecting member may be equivalent to the radial width dimension of the cage body.

  The length dimension of the connecting member in the axial direction has a length sufficient to prevent the spanned wire from contacting the ball.

  The wire is formed of a material whose linear expansion coefficient is smaller than that of the cage body made of synthetic resin. An example is a wire made of steel (including ordinary steel and special steel), but is not limited to this. If the condition that the linear expansion coefficient is smaller than that of the cage body is satisfied, a metal other than steel ( For example, it may be a copper or aluminum alloy) or a resin (including a fiber reinforced resin). Moreover, about the cross-sectional shape of a wire, circular, a rectangle, etc. are not specifically limited. Moreover, the wire should just be the cyclic | annular form which both ends closed, and the polygon which connects connection members linearly other than circular may be sufficient. Furthermore, the wire may be composed of a single wire, or may be formed by twisting a plurality of wires to increase rigidity.

  According to the ball bearing retainer of the present invention, by holding the annular wire rod between the connecting members projecting in the same direction as the ball retaining claws constituting the pocket, the centrifugal force at the time of high speed rotation allows the ball retaining The deformation of the claws outward in the radial direction can be suppressed by an annular wire that is stretched between the connecting members. Thus, it is a simple structure which only hangs | hangs an annular wire between connection members, can suppress a deformation | transformation inexpensively, can prevent interference with a ball | bowl, and can aim at the reduction in torque of a ball bearing.

  Further, since the connecting members are connected to each other by the wire material, the lubricating oil does not prevent the oil from entering the pocket, and sufficient lubrication can be obtained even during high-speed rotation, thereby preventing the seizure of balls.

  Furthermore, since the linear expansion coefficient of the wire is smaller than the linear expansion coefficient of the cage main body, the degree of expansion of the wire becomes smaller than the expansion of the rigid resin-made cage main body due to heat generation during high-speed rotation. That is, the outward expansion of the cage body in the radial direction can be suppressed by the wire, and the deformation of the ball holding claws in the radial direction outward due to the temperature rise can also be suppressed.

  As a specific configuration of the ball bearing retainer of the present invention, a concave portion may be formed on the radially outer surface of the connecting member, and a wire rod may be hooked on the concave portion.

  In this case, the diameter of the annular wire is preferable because the size of the ring-shaped wire just fitted in the recess is caught in the retaining state.

  It is preferable to provide the recess in the vicinity of the distal end of the connecting member because the force acting on the connecting member of the wire is improved and deformation in the radially outward direction can be further suppressed.

  As another specific configuration of the ball bearing cage of the present invention, a groove may be formed at the tip of the connecting member, and a wire rod may be press-fitted into the groove.

  In this case, as the shape of the groove, for example, the groove entrance is narrower than the wire and the inner part is substantially the same size as the wire, or the entire groove is press-fitted slightly narrower than the wire. .

  According to the present invention, the ball holding claws constituting the pocket can be prevented from being deformed radially outwardly with a simple structure at low cost, and the torque of the ball bearing used in oil lubrication or grease lubrication can be reduced. Can be planned.

(Embodiment 1)
A first embodiment of the present invention will be described with reference to FIGS.

  1 is a partial sectional view of a ball bearing, FIG. 2 is a perspective view of a ball bearing cage, FIG. 3 is a partial sectional view of the ball bearing cage, and FIG. 4 is a partial side view of the ball bearing cage.

  As shown in FIG. 1, the ball bearing 1 according to the first embodiment includes an outer ring 2 having an outer ring raceway 3 on an inner peripheral surface and an inner ring 4 having an inner ring raceway 5 on an outer peripheral surface. A plurality of balls 6 are provided between the inner ring raceway 5 and the inner ring raceway 5 so as to freely roll. The outer ring 2, the inner ring 4, and the ball 6 are each made of a steel material such as alloy steel.

  Grease is sealed inside the bearing on both sides in the axial direction of the space between the outer ring 2 and the inner ring 4, or foreign matter in oil is prevented from entering the bearing due to dust floating on the outside or oil lubrication. Seal members 7 and 7 are provided. As the seal member 7, for example, a contact type that is attached and fixed to the outer ring 2 and whose lip portion is in sliding contact with the inner ring 4, a non-contact type that forms a labyrinth with the inner ring 4, and a member that is attached and fixed to the inner ring 4. Etc. Note that the seal member 7 may be provided only on one side in the axial direction or may not be provided.

  The plurality of balls 6 are held by a cage 8 so as to be freely rollable at a predetermined pitch in order to prevent mutual contact. The cage 8 is called a crown type, and is integrally formed by injection molding a synthetic resin. That is, it is called a one-piece crown because of the advantages of a molding die and assemblability.

  The resin material of the crown type cage 8 includes polyamide (nylon 6, nylon 66, nylon 46) resin, polyacetal resin, polyether ether ketone resin (PEEK), polyphenylene sulfide resin (PPS), polytetrafluoroethylene (PTFE). ), Or a composite material or the like reinforced by containing about 10 to 40% by weight of a short fiber (reinforcing material) such as glass fiber or carbon fiber.

  As shown in FIG. 2, the crown-shaped cage 8 includes an annular annular base body 9 and a plurality of sets of pockets 10 provided on one side of the annular base body 9 so as to be substantially equidistant around the circumference. Each pocket 10 includes a pair of ball-holding claws 12 and 12 that are arranged at a distance from each other at the tip end of a partitioning projecting piece 11 that exists between pockets 10 adjacent in the circumferential direction. The annular main body 9, the pocket 10, the partitioning protrusion 11, and the ball holding claw 12 constitute a cage main body 19.

  The mutually opposing surfaces of the pair of ball holding claws 12, 12 constituting each pocket 10 are concentric spherical concave surfaces. The opening size of the pocket entrance portion which is the open end of the pocket 10 (the distance between the tips of the opposing pair of ball holding claws 12, 12) is an undercut shape which is about 10% smaller than the maximum pocket diameter (the diameter of the pocket inner surface). It has become. The pocket inner surface may be a cylindrical surface. Each ball 6 can be rolled into each pocket 10 in a drop-off prevention posture by pushing between the pair of ball holding claws 12 and 12 while elastically expanding the distance between the ball holding claws 12 and 12. Retained.

  In this way, by providing the ball holding claws 12 on both sides in the circumferential direction on the free end side of each partitioning projecting piece 11, a recess 13 is formed between them, especially in grease lubrication, The recess 13 is used as a grease storage part to supply grease to the pocket 10. The grease supplied to the pocket 10 has a role of gradually oozing out the base oil during rotation and is transferred to the races 3 and 5 of the outer ring 2 and the inner ring 4 through the balls 6 to lubricate the bearings. Further, the grease also has a role of performing initial lubrication by scattering from the concave portion 13 to the friction portion at the initial stage of rotation.

  Further, as shown in FIGS. 3 and 4, in each concave portion 13 of the crown type cage 8, a prismatic connecting member 14 is integrally formed with the partitioning projecting piece 11 so as to project in the opening direction of the pocket 10. ing. The radial width dimension of the connecting member 14 is formed smaller than the radial width dimension of the partitioning projecting piece 11, and the connecting member 14 projects from the radially inner side of the partitioning projecting piece 11. Further, the length dimension of the connecting member 14 in the axial direction has a length sufficient to prevent the spanned wire 18 from contacting the ball 6. Further, a curved recess 16 is formed in the vicinity of the distal end of the radially outer surface 15 of the connecting member 14.

  Then, the annular wire 18 is hooked over the curved concave portion 16 of each connecting member 14. That is, the wire 18 is fitted over the curved recess 16 so as to get over the tip 17 of the radial outer surface 15 of each connecting member 14. At this time, the resin connection member 14 is elastically deformed radially inward, and the wire 18 can be easily fitted. The radial outer surface of the distal end portion 17 is slightly smaller than the radial outer surface 15 so that the wire 18 can be easily fitted and the wire 18 fitted in the curved recess 16 can be prevented from coming off. I am short. The overall structure of the crown type cage 8 on which the wire 18 is hooked is as shown in FIG. In addition, since the connecting member 14 protrudes radially inward of the partitioning projecting piece 11, as shown in FIG. 1, the wire 18 fitted in the curved recess 16 has a radial width dimension of the annular base body 9. It is possible to prevent the inner ring from sliding on the inner peripheral surface of the outer ring 2.

  As the wire 18, a circular ring formed by welding both ends of a steel cross-section wire having a linear expansion coefficient smaller than that of the cage body 19 made of synthetic resin is used. The annular wire 18 made of steel wire has sufficient rigidity to prevent the tip of the ball holding claw 12 from being deformed radially outward by the centrifugal force when the ball bearing 1 rotates at high speed. Prepare. Further, the diameter of the annular wire 18 is such that it is just fitted into the curved recess 16 so that it can be prevented from coming off.

  According to the ball bearing retainer configured in this way, by passing the annular wire 18 between the connecting members 14 projecting in the same direction as the ball holding claws 12 constituting the pocket 10, the wire 18 is It acts to suppress the ball holding claws 12 from being deformed radially outward, and the ball retaining claws 12 can be prevented from being deformed radially outward by the centrifugal force during high-speed rotation. . Thus, it is a simple structure which only spans the cyclic | annular wire 18 between the connection members 14, can suppress a deformation | transformation cheaply, can prevent interference with the ball | bowl 6, and can aim at the low torque reduction of the ball bearing 1. FIG. it can.

  Further, since the connecting members 12 are connected to each other by the wire 18, the lubricating oil stored in the concave portion 13, especially the grease in the case of grease lubrication, is not prevented from entering the pocket 10 and is rotated at a high speed. Even at times, sufficient lubrication can be obtained and seizure of the balls 6 can be prevented.

(Embodiment 2)
A second embodiment of the present invention will be described with reference to FIGS.

  5 is a partial sectional view of the ball bearing, FIG. 6 is a perspective view of the ball bearing cage, FIG. 7 is a partial sectional view of the ball bearing cage, FIG. 8 is a partial side view of the ball bearing cage, FIG. (A) is a partial expanded sectional view of the cage for ball bearings.

  In addition, the same part as the example shown in FIGS. 1 thru | or FIG.

  In the second embodiment, the connecting members 21 projecting from the respective concave portions 13 of the crown type cage 8 are different from the connecting members 14 of the first embodiment.

  That is, the connecting member 21 is formed in a prismatic shape, and is formed integrally with the partitioning projecting piece 11. A groove 22 is formed at the tip of the connecting member 21. In the groove 22, the back portion 23 is formed to be approximately the same size as the wire 18, and the inlet 24 is narrower than the wire 18. The wire 18 is press-fitted from the narrow inlet 24, pushes the front end of the resin connection member 21, gets over the narrow inlet 24, and fits into the inner part 23. In this manner, the entire structure of the crown-shaped cage 8 is as shown in FIG. 6 by press-fitting the annular wire 18 into the groove 22 of each connecting member 21.

  Also in the ball bearing retainer configured as described above, the ball retaining pawl 12 constituting the pocket 10 can be prevented from being deformed radially outwardly with a simple structure, and the low torque of the ball bearing 1 can be suppressed. Can be achieved.

  As shown in FIG. 9B, the groove 25 formed at the tip of the connecting member 21 may be slightly narrower than the wire 18 over the entire groove. In this case, it is possible to suppress the ball holding claws 12 from being deformed outwardly in the radial direction by being press-fitted into the grooves 25 with the interference margins, so as to be passed over the respective connecting members 21.

  INDUSTRIAL APPLICABILITY The present invention is useful as a crown type synthetic resin retainer that holds balls with medium and large-sized deep groove ball bearings used in oil lubrication and grease lubrication.

The fragmentary sectional view of the ball bearing in Embodiment 1 of the present invention The perspective view of the cage for ball bearings in Embodiment 1 of the present invention. The fragmentary sectional view of the cage for ball bearings in Embodiment 1 of the present invention. The partial side view of the ball bearing retainer in Embodiment 1 of this invention The fragmentary sectional view of the ball bearing in Embodiment 2 of the present invention The perspective view of the ball bearing retainer in Embodiment 2 of this invention Partial sectional view of a ball bearing cage according to Embodiment 2 of the present invention. Partial side view of the ball bearing retainer according to Embodiment 2 of the present invention. Partial expanded sectional view of the ball bearing retainer according to Embodiment 2 of the present invention. Partial sectional view of a conventional ball bearing Perspective view of cage for ball bearing in conventional example

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Ball bearing 2 Outer ring 4 Inner ring 6 Ball 8 Crown type retainer 9 Annular base 10 Pocket 12 Ball retaining claws 14, 21 Connecting member 16 Curved recess 18 Wire material 19 Retainer body 22, 25 Groove

Claims (5)

Holds a crown-shaped synthetic resin with a plurality of pockets that are inserted and held by a pair of ball-holding claws that are open at one end in the axial direction and are formed in a substantially equal circumference and project toward the opening. The container body,
Between the adjacent pockets, a plurality of connecting members projecting on one end side in the axial direction,
An annular wire rod that spans between the connecting members and prevents the ball holding claws from being deformed radially outward;
A ball bearing retainer.   The ball bearing retainer according to claim 1, wherein a concave portion is formed on a radially outer surface of the connecting member, and the wire is hooked on the concave portion.   The ball bearing retainer according to claim 1, wherein a groove is formed at a tip of the connecting member, and the wire is press-fitted into the groove.   The ball according to any one of claims 1 to 3, wherein the wire is formed of a material whose linear expansion coefficient is smaller than that of the synthetic resin cage body. Bearing cage.   The ball bearing retainer according to claim 4, wherein the wire is made of a steel wire.

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