CN114593152A - Cage for a rolling bearing and rolling bearing - Google Patents

Abstract

The invention relates to a cage for a rolling bearing and a rolling bearing. The cage has a cage ring (31); intermediate beams distributed in the circumferential direction, wherein the intermediate beams project from the axial end faces of the cage ring (31), and pockets for receiving rolling bodies (4) of the rolling bearing are formed between every two adjacent intermediate beams; and guide beams (32) distributed in the circumferential direction, wherein the guide beams (32) extend from the axial end faces of the cage ring (31) and are configured between adjacent pockets, and the guide beams (32) can be matched with the outer ring (1) of the rolling bearing to realize the outer diameter guide of the cage. The rolling bearing comprises an outer ring (1), an inner ring (2), a rolling body (4) and the retainer (3), wherein the retainer (3) is matched with the outer ring (1) to realize outer diameter guide.

Description

Cage for a rolling bearing and rolling bearing

Technical Field

The invention relates to the field of bearings. The invention relates in particular to a cage for a rolling bearing and to a rolling bearing comprising such a cage.

Background

A conventional rolling bearing includes an outer ring and an inner ring that are concentrically arranged, and includes rolling bodies arranged between the outer ring and the inner ring. The rolling bearing further comprises a cage to isolate the rolling bodies and to guide and retain the rolling bodies within the bearing. One common cage design is the snap-in cage design, which designs one end of the cage to be open, and the cage can be installed axially on the premise of providing sufficient axial spacing. For example, US patent document US 6,416,230B1 discloses a snap-type cage for deep groove ball bearings. For another example, chinese patent document CN 101978181 also discloses a ball bearing retainer and a ball bearing including the same. Patent document WO 2015/090304a1 also discloses a snap-type holder.

However, with the development of automobile electrification, the rotational speed of rolling bearings such as deep groove ball bearings is increasingly demanded. The cage according to the present solution is usually guided by rolling elements, and in some applications at high rotational speeds, a cage fracture may occur. The main reason for failure due to breakage is that the centrifugal force of the cage is proportional to the square of the rotational speed, and at high rotational speeds the centrifugal force increases substantially, and the load borne by the cage exceeds the strength limit of the material, particularly nylon material.

Disclosure of Invention

The object of the present invention is therefore to provide a cage, in particular a snap-in cage, for a rolling bearing, which has a long service life and can be adapted to high-speed applications.

The above object is achieved in a first aspect of the present invention by a cage for a rolling bearing. The cage provided herein has: a cage ring; intermediate beams distributed in the circumferential direction, wherein the intermediate beams extend from the axial end face of the retainer ring, and pockets for accommodating rolling bodies of the rolling bearing are formed between every two adjacent intermediate beams; and guide beams distributed along the circumferential direction, wherein the guide beams extend out from the axial end face of the retainer ring and are configured between adjacent pockets, and the guide beams can be matched with the outer ring of the rolling bearing to realize the outer diameter guide of the retainer.

In the context of the present description, a rolling bearing comprises an outer ring and an inner ring which are arranged coaxially and rolling bodies which are arranged between the outer ring and the inner ring. The cage is coaxially disposed between the outer race and the inner race to accommodate and isolate the respective rolling bodies. The rolling bodies can be configured as any type of rolling body that matches a snap cage. The rolling bearing is preferably designed as a ball bearing, for example as a deep groove ball bearing. In this case, the rolling elements are spherical rolling elements, i.e. balls.

In the context of the present description, unless otherwise specified, "axial", "radial" and "circumferential" directions are based on the axis of rotation of the rolling bearing, wherein "axial" is the direction parallel to or coinciding with the axis of rotation, "radial" is the direction perpendicular to the axis of rotation, and "circumferential" is the direction around the axis of rotation.

The cage is configured as a snap-in cage. The cage can be used for a rolling bearing with a single row of rolling bodies, in which case intermediate webs distributed in the circumferential direction project from one axial end face of the cage ring in the same axial direction, whereby a row of pockets distributed in the circumferential direction is formed on the axial side. The cage can also be used for rolling bearings with double rows of rolling elements, in which case two rows of circumferentially distributed intermediate beams project in each case from the two axial end faces of the cage ring in the opposite axial direction, whereby a row of circumferentially distributed pockets is formed on each axial side of the cage ring. In the case of cages for double row rolling elements, the pockets of the cage in both rows can be arranged in axial alignment, one after the other, and also in axial non-alignment, i.e. offset in the circumferential direction.

Advantageously, the cage is made in one piece. The holder may be made of a metallic material or a non-metallic material. The non-metallic cage material is, for example, a polymer or a composite thereof, such as nylon. Particularly advantageously, the cage is a nylon cage. Therefore, the holder has better toughness after certain humidity is obtained. In addition, the nylon cage is lighter than a metal cage, has small centrifugal force, and is suitable for high-rotation-speed application occasions.

By means of the guide webs distributed in the circumferential direction, the cage can be guided with an outer diameter by the shoulders of the outer ring, so that the cage and the rolling bodies can be supported by the outer ring during operation with centrifugal forces. The load that the cage, especially nylon cages are required to carry does not easily exceed the strength limit of the material, especially nylon material. Therefore, the retainer is not easily broken and has a long service life. Here, the guide girders are constructed at the radial outside of at least two, preferably a plurality of, more preferably each intermediate girder or at the same radial height as the intermediate girders. The cage rings of the cage and the guide beams together form a guide surface in the circumferential direction. The guide surface has an axial dimension which is sufficiently long to be able to bridge axially distributed abutment shoulders of the outer ring, so that the centrifugal force of the cage is stably transmitted to the outer ring.

In a preferred embodiment, the free end of the guide beam is configured with a projection projecting radially outwards. In this case, the axial end face of the projection facing the cage ring can serve as a stop at the outer ring of the rolling bearing. Therefore, when the retainer is operated at a high rotation speed and the retainer has a tendency to be pulled out from the rolling bearing in the axial direction, the retainer can be positioned in the axial direction by the boss, thereby preventing the retainer from being pulled out from the rolling bearing. The cage according to the present embodiment can be axially mounted like a cage of a standard design. When the retainer is installed, the retainer can enter the outer ring from one end of the boss along the axial direction. In the process, the projection is introduced into the outer ring, for example by means of a chamfer, and the free end of the guide beam is elastically deformed toward the radial inside due to the elasticity of, in particular, a nylon material. When the boss moves through the retaining shoulder of the outer ring, the original shape is recovered and the boss is matched with the axial end part of the outer ring, so that the axial limiting of the retainer is formed.

In an advantageous embodiment, a guide web is formed between each two adjacent pockets. In this case, the number of the guide beams corresponds to the number of the intermediate beams for forming the pockets. The guide webs are formed here radially outside the respective intermediate webs or at the same radial level as the intermediate webs, so that the cage can be guided stably by the outer ring with an outer diameter.

In a preferred embodiment, the free end of the intermediate beam is designed as a catch, which projects at least partially on both sides in the circumferential direction. The openings formed by the two claws of the same pocket are designed such that the opening size is smaller than the diameter of the balls while ensuring assembly. The two jaws and the cage ring thereby together perform an axial limiting function.

In this case, the inner side of the catch facing the respective pocket is preferably spherical. Accordingly, the rolling bodies can be designed as balls. The contour of the circumferential contact surface of the cage for the rolling bodies thereby matches the contour of the rolling bodies, so that the cage can provide a stable circumferential support for the rolling bodies. The radial dimension of the detent is not limited, but the radial limitation of the rolling bodies can be implemented completely or partially by the inner ring and the outer ring of the rolling bearing.

Here, preferably, the radially outer side face of the pawl is lower than the radially outer side face of the guide beam in the radial direction. Thus, on the one hand, the intermediate beam or the clamping jaw does not interfere with the outer diameter guidance between the guide beam and the stop shoulder of the outer ring; on the other hand, a lubricating medium can be stored in the space between the claws of the cage and the outer ring in the radial direction and between the respective guide beams of the cage in the circumferential direction, so that the lubrication of the rolling bearing can be improved; on the other hand, the claws have a smaller radial dimension, which contributes to a lightweight design of the cage.

In this case, a gap is preferably formed radially between the catch and the guide beam. In particular when the intermediate beam and the guide beam are substantially at the same circumferential position, the radial gap can be formed, for example, by removing material from the radially outer side of the claw and/or from the radially inner side of the intermediate beam, so that space can be reserved for demolding during the production of the cage and for the deformation of the claw during assembly.

In a preferred embodiment, a cutout facing away from the pocket opening in the axial direction is formed in the region of the holder between the pockets. This saves material and reduces the weight of the cage.

The above object is achieved in a second aspect of the present invention by a rolling bearing. The rolling bearing comprises an outer ring, an inner ring, rolling bodies and a cage according to the above-described embodiments, wherein the cage is guided with an outer diameter by means of the outer ring.

In a preferred embodiment, the free end of the guide beam of the cage is configured with a lug which projects radially outwards and with an annular groove at the axial end of the outer ring, wherein the lug can abut against the annular groove to stop the cage in the axial direction. In this case, the radial clearance between the radially outer surface of the projection and the inner circumferential surface of the annular groove is greater than the radial clearance between the guide surface of the cage, which is formed by the cage ring and the guide webs, and the stop shoulder of the outer ring, so that the outer-diameter guidance of the cage by means of the outer ring is ensured.

Drawings

Preferred embodiments of the present invention are schematically illustrated in the following with reference to the accompanying drawings. The attached drawings are as follows:

fig. 1 is a perspective view of a rolling bearing according to a preferred embodiment, wherein an outer ring of the rolling bearing is partially removed;

fig. 2 is a perspective view of the rolling bearing according to fig. 1 from another angle of view;

fig. 3 is a half sectional view of the rolling bearing according to fig. 1;

fig. 4 is a perspective view of a cage of the rolling bearing according to fig. 1;

fig. 5 is a perspective view of the cage according to fig. 4 from another perspective; and

fig. 6 is a perspective view of a part of the cage according to fig. 4.

Detailed Description

Fig. 1 and 2 show perspective views of a rolling bearing according to a preferred embodiment of the invention from different perspectives, wherein the outer ring 1 of the rolling bearing is partially removed to show the interior of the rolling bearing for clarity.

The rolling bearing according to the present embodiment is configured as a deep groove ball bearing. As shown in fig. 1 and 2, the rolling bearing includes an outer ring 1 and an inner ring 2 arranged coaxially and a row of rolling bodies 4 arranged between the outer ring 1 and the inner ring 2. The rolling bodies are designed here as balls 4. The rolling bearing also comprises a cage 3 made in one piece of nylon material.

Fig. 3 shows a half sectional view of the rolling bearing according to the present embodiment. Fig. 4 and 5 show perspective views of the cage 3 of the rolling bearing according to the present embodiment from different perspectives. As shown in fig. 3 to 5, the holder 3 is configured as a snap-in holder. The cage 3 comprises a cage ring 31, intermediate beams distributed in the circumferential direction and guide beams 32 distributed in the circumferential direction.

Fig. 6 shows a partial perspective view of the cage 3. As shown in fig. 4 to 6, the intermediate beams project from the axial end faces of the cage ring 31, and pockets for receiving rolling bodies of the rolling bearing, i.e., the balls 4, are formed between each two adjacent intermediate beams. The free ends of the center bar are in this case designed as claws 34, which each project at least partially on both sides in the circumferential direction. The sides of the two claws 34 of the same pocket facing each other are configured as concave spherical shapes so as to match the contour of the ball 4 to provide stable support of the ball 4 in the circumferential direction. The distance between the free ends of the two claws 34 of the same pocket, i.e. the size of the opening formed by the two claws 34, is designed such that the size of the opening is smaller than the diameter of the ball 4 while ensuring assembly, whereby the two claws 34 and the cage ring 31 together achieve an axial stop of the ball 4. The radial positioning of the balls 4 is achieved in part by the shoulders 11, 12 of the outer ring 1 and the shoulders of the inner ring 2 of the rolling bearing.

As shown in fig. 2 to 5, the guide beam 32 projects from an axial end face of the holder ring 31. In the present embodiment, the guide beams 32 are arranged at each intermediate beam in the circumferential direction and are configured radially outside the respective intermediate beam. The cage ring 31 and the guide beams 32 of the cage 3 together form a guide surface in the circumferential direction. The axial dimension of the guide surfaces is sufficiently long to be able to bridge the axially extending abutment shoulders 11, 12 of the outer ring 1. The cage 3 can be guided with an outer diameter by means of the guide surfaces and the shoulders 11, 12 of the outer ring, whereby the centrifugal forces of the cage 3 and the balls 4 during operation can be carried by the outer ring 1. At this time, the load that the cage 3 needs to carry does not exceed the strength limit of the nylon material, and the cage 3 is therefore not easily broken and has a long service life.

As shown in particular in fig. 3, the free end of the guide beam 32 is configured with a projection 33 which projects radially outwards. The axial end of the outer ring 1 remote from the cage ring 31 constitutes an annular groove. Here, an axial end face of the boss 33 facing the holder ring 31 can abut against the axial end face 13 of the annular groove portion. Therefore, when the cage 3 is operated at a high rotation speed and the cage 3 tends to come out of the rolling bearing in the axial direction, the cage 3 can be positioned in the axial direction by the bosses 33, thereby preventing the cage 3 from coming out of the rolling bearing. Here, the radial clearance between the radially outer surface of the boss 33 and the inner circumferential surface 14 of the annular groove portion is larger than the radial clearance between the guide surface constituted by the holder ring 31 and the guide beams 32 and the shoulder portions 11, 12 of the outer ring 1, thereby ensuring the outer diameter guide of the cage 3 by the outer ring 1.

In the present embodiment, as shown in fig. 3 and 6, the radially outer side surface of the pawl 34 is lower than the radially outer side surface of the guide beam 32 in the radial direction. The claws 34 thus do not interfere with the outer diameter guidance between the guide beams 32 and the shoulders 11, 12 of the outer ring 1. At the same time, a lubricating medium is stored in the spaces between the claws 34 of the cage 3 and the outer ring 1 in the radial direction and between the respective guide beams 32 of the cage 3 in the circumferential direction, so that the lubrication of the rolling bearing can be improved. Furthermore, the claws 34 have a smaller radial dimension, thereby facilitating a lightweight design of the cage 3.

In the present embodiment, as shown in fig. 3, a gap is formed between the claws 34 and the guide beam 32 in the radial direction, so that it is possible to reserve a space for mold release during the manufacture of the cage 3 and deformation of the claws 34 at the time of assembly.

In the present embodiment, a cutout 35 is formed on the back side of the holder 3, i.e., on the side facing away from the pocket. The recess 35 is open axially on the side facing away from the pocket. The cutouts 35 are distributed in the circumferential direction at the respective intermediate beams. The provision of the cutout 35 makes it possible to save material and to reduce the weight of the cage 3.

The retainer 3 of the present embodiment can be axially mounted to a standard design retainer. When mounting, the cage 3 can enter the outer ring 1 from one end of the boss 33. In this process, the boss 33 is introduced into the outer race 1 by means of chamfering, and the guide beam 32 of the cage 3, particularly at the boss 33, is elastically deformed toward the radially inner side due to the elasticity of the nylon material. When the boss 33 moves past the shoulders 11, 12 of the outer ring 1, the boss 33 returns to its original shape and engages with the annular groove portion of the outer ring 1, thereby forming an axial stop for the cage 3.

Although possible embodiments have been described by way of example in the above description, it should be understood that numerous embodiment variations exist, still by way of combination of all technical features and embodiments that are known and that are obvious to a person skilled in the art. It should also be appreciated that the exemplary embodiment or exemplary embodiments are only examples, and are not intended to limit the scope, applicability, or configuration of the invention in any way. From the foregoing description, one of ordinary skill in the art will more particularly provide a technical guide to convert at least one exemplary embodiment, wherein various changes may be made, particularly in matters of function and structure of the components described, without departing from the scope of the following claims.

List of reference numerals

1 outer ring

11 shoulder

12 stop shoulder

13 axial end face of the annular groove portion

14 inner peripheral surface of annular groove portion

2 inner ring

3 holding rack

31 cage ring

32 guide beam

33 boss

34 claw

35 hollow part

4 rolling elements, balls

Claims (10)

1. Cage (3) for a rolling bearing, the cage (3) having:

a holder ring (31);

intermediate beams distributed in the circumferential direction, wherein the intermediate beams project from the axial end faces of the cage ring (31) and between every two adjacent intermediate beams a pocket is formed for accommodating a rolling body (4) of the rolling bearing; and

guide webs (32) distributed in the circumferential direction, wherein the guide webs (32) project from the axial end faces of the cage ring (31) and are formed between adjacent pockets, wherein the guide webs (32) can be used to guide the outer diameter of the cage (3) in cooperation with the outer ring (1) of the rolling bearing.

2. Cage (3) according to claim 1, wherein the free ends of the guide beams (32) are configured with a projection (33) protruding towards the radial outside.

3. Cage (3) according to claim 1, wherein the guide beams (32) are configured between every two adjacent pockets.

4. Cage (3) according to claim 1, wherein the free end of the central beam is configured with claws (34) that project at least partially towards both sides in the circumferential direction, respectively.

5. Cage (3) according to claim 4, wherein the inner side faces of the claws (34) facing the respective pocket are designed in spherical form.

6. Cage (3) according to claim 4, wherein the radially outer side of the jaws (34) is lower than the radially outer side of the guide beams (32) in the radial direction.

7. Cage (3) according to claim 6, wherein a clearance is configured radially between the jaws (34) and the guide beam (32).

8. Cage (3) according to claim 1, wherein a cutout (35) facing away from the pocket opening in the axial direction is formed in the region between the pockets.

9. Rolling bearing comprising an outer ring (1), an inner ring (2), rolling bodies (4) and a cage (3) according to one of the preceding claims, wherein the cage (3) is guided with the outer diameter by means of the outer ring (1).

10. Rolling bearing according to claim 9, wherein the free ends of the guide beams (32) of the cage (3) are configured with a boss (33) protruding towards the radial outside and an annular groove portion is configured at the axial end of the outer ring (1), wherein the boss (33) can abut against the annular groove portion to axially stop the cage (3).

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