Ball bearing retainer and bearing

Abstract

The invention discloses a ball bearing retainer and a bearing, and relates to the technical field of bearings, the ball bearing retainer comprises a main ring and an auxiliary ring which can be buckled with each other, after the main ring and the auxiliary ring are buckled with each other, a plurality of balls are positioned, and a first inner ring and a first outer ring are fixedly arranged on the side wall, facing the auxiliary ring, of the main ring; the same positions of the first inner ring and the first outer ring are provided with abutting arc grooves used for abutting against the balls, and the abutting arc grooves allow the balls to move from the openings to the positions abutting against the abutting arc grooves. A second inner ring and a second outer ring are fixedly arranged on the side wall, facing the main ring, of the auxiliary ring, and the abutting arc grooves are also formed in the same positions of the second inner ring and the second outer ring; when the main ring and the auxiliary ring are mutually buckled and fixed, the first inner ring and the second inner ring are mutually clamped, and the first outer ring and the second outer ring are mutually clamped, so that a ring cavity is formed between the main ring and the auxiliary ring. The ball bearing has the advantages that heat generated by the ball bearing in a high-speed rotation scene is reduced, the rolling smoothness of the balls is improved, and the service life of the bearing is prolonged.

Description

Technical Field

[0001] The present application relates to the technical field of bearings, and in particular to a ball bearing retainer and a bearing. Background Art

[0002] Ball bearings are a type of bearing. By installing the balls between the inner ring and the outer ring, the balls can withstand larger loads. The balls in the ball bearings are generally restricted in position by the installed cage and the stability of the ball rotation is improved.

[0003] The patent for bearings and cages with application number CN202010160513.4 discloses a bearing cage structure. Common ball bearing cages are all of this wrapping structure. During the installation of the ball bearing, the inner ring is generally placed on one side of the outer ring, and a corresponding number of balls are placed between the inner ring and the outer ring. The balls are then clamped in the arc grooves of the inner and outer rings by moving the inner ring to the middle position, and then the balls are fixed in position by inserting two cages to complete the basic installation of the bearing. The two cage parts are generally fixed by riveting or other fixing methods.

[0004] In order to ensure the stability of ball rolling and reduce the occurrence of shaking, the cage and the ball are usually in a close fit. However, when this type of bearing rotates at high speed, due to the large contact area between the cage and the ball, the ball rotation will generate a lot of heat, which will not only change the size of the cage and cause disturbance clearance, but also cause the lubricating grease to deteriorate and reduce the lubrication effect, thereby increasing wear and reducing life. However, the cage needs to be stably fitted to the ball to maintain the stability of the ball rotation. Therefore, in a high-speed use environment, how to make the ball rotate stably and with low wear is a design difficulty, which directly affects the use and service life of the bearing. Summary of the invention

[0005] In order to improve the defects of the existing ball bearing cage structure such as greater wear and high heat generation under high-speed use environment, the present application provides a ball bearing cage and a bearing.

[0006] The present application provides a ball bearing cage adopting the following technical solution: A ball bearing retainer, comprising a main ring and a secondary ring that can be buckled with each other, wherein the main ring and the secondary ring are buckled with each other to position a plurality of balls, a first inner ring and a first outer ring are fixedly provided on the side wall of the main ring facing the secondary ring, the diameter of the first inner ring is smaller than the diameter of the first outer ring, and abutment arc grooves for abutting against the balls are provided at the same position of the first inner ring and the first outer ring, the abutment arc grooves are arranged away from an opening at one end of the main ring and are used for the balls to move from the opening to a position abutting against the abutment arc grooves; A second inner ring and a second outer ring are fixedly provided on the side wall of the secondary ring facing the primary ring. The diameter of the second inner ring is smaller than that of the second outer ring. The abutting arc groove is also provided at the same position of the second inner ring and the second outer ring. When the main ring and the secondary ring are buckled and fixed to each other, the first inner ring and the second inner ring are clamped to each other, and the first outer ring and the second outer ring are clamped to each other, so that an annular cavity is formed between the main ring and the secondary ring. At this time, the abutting arc grooves of the first inner ring and the second inner ring are pressed against the bottom of the ball together, and the abutting arc grooves of the first outer ring and the second outer ring are pressed against the top of the ball together.

[0007] Optionally, the length of the first outer ring is greater than the length of the first inner ring, and the length of the second inner ring is greater than the length of the first inner ring; A first ring groove is provided on the side wall of the first outer ring facing the ring cavity, and is in contact with the second outer ring, and is used for the second outer ring to be clamped therein; A second annular groove is provided on the side wall of the second inner ring facing the annular cavity, and the first inner ring is clamped therein; A support frame is fixed between the first inner ring and the first outer ring, and the support frame can be tightly pressed against the first inner ring and the second outer ring.

[0008] Optionally, the end of the support frame is set to be tilted excessively.

[0009] Optionally, a guide groove inclined outward is provided at a position of the abutting arc groove of the first outer ring facing the second outer ring, and a guide groove is also provided at a position of the abutting arc groove of the second inner ring facing the first inner ring.

[0010] Optionally, the first outer ring end can abut against the secondary ring, and the second inner ring end can abut against the main ring end.

[0011] Optionally, the positions of the first outer ring, the first inner ring, the second outer ring and the second inner ring between the abutting arc grooves are all set as avoidance holes, and the avoidance holes are connected to the ring cavity.

[0012] Optionally, the first inner ring and the first outer ring are fixedly provided with first support plates at positions close to the avoidance hole, and the two first support plates on both sides of the avoidance hole are fixedly provided with first mounting plates; The second inner ring and the second outer ring are fixedly provided with second support plates at positions close to the avoidance hole, and the two second support plates on both sides of the avoidance hole are fixedly provided with second mounting plates; The first mounting plate and the second mounting plate are both provided with mounting holes opposite to each other, and the main ring and the auxiliary ring are provided with insertion holes opposite to the mounting holes; The same fixing rod is inserted into the two mounting holes, and two sets of opposite buckle structures are fixed on the fixing rod. The buckle structures can pop open after passing through the mounting holes, and the two ends of the buckle structures can be pressed against the first mounting plate and the second mounting plate and tightened against each other.

[0013] Optionally, the main ring and the secondary ring are both spaced apart and provided with heat dissipation holes communicating with the ring cavity.

[0014] Optionally, the inner wall of the abutting arc groove is in the shape of a circular arc protrusion.

[0015] A ball bearing provided in this application adopts the following technical solution A ball bearing comprises the above-mentioned retaining frame, and also comprises balls, an inner ring, an outer ring and an oil seal ring. The circumferential outer wall of the inner ring and the circumferential inner wall of the outer ring are both provided with arc grooves. There are multiple balls, which abut against the arc grooves of the inner ring and the outer ring so that the inner ring is located in the middle of the outer ring. The retaining frame positions the balls, and the oil seal ring is installed between the inner ring and the outer ring to seal the retaining frame therein.

[0016] In summary, the present application includes at least one of the following beneficial technical effects: 1. The interlocking structure of the first inner ring, the second inner ring, the first outer ring and the second outer ring forms a ring cavity structure while stably limiting the ball through the abutting arc groove, thereby reducing the friction of the ball rotation and improving the heat dissipation effect of the ball through the ring cavity structure and the heat dissipation holes, and also realizing the lightweight design of the cage; 2. The design of the first ring groove and the second ring groove can not only provide support for the second outer ring and the first inner ring, but also cooperate with the guide groove to realize automatic guiding and positioning of the ball, and can also realize stable clamping and pre-fixing by utilizing the support frame structure, which effectively improves the structural strength and structural rationality, and improves the efficiency of the installation combination; 3. The setting of the avoidance hole can facilitate the heat dissipation of the ring cavity on the one hand, and on the other hand, support the ring plates through the support plate structure to improve the structural stability, and can realize the installation and fixation of the main ring and the secondary ring by inserting the fixing rod after the mounting plates abut against each other, thereby improving the fixing efficiency and the stability of the installation and fixation, and using the snap-on structure to improve the stability of the combination of the two mounting plates. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is a schematic diagram of the structure of Example 1 of the present application; Figure 2 is an explosion diagram of Example 1 of the present application; Figure 3 This is Example 1 of the present application Figure 2 An enlarged view of part A is shown in FIG. Figure 4 is a partial cross-sectional view showing the ball abutment state of Example 1 of the present application; Figure 5 is a schematic diagram of the structure of Example 2 of the present application; Figure 6 It is a schematic diagram of the explosion of Example 2 of the present application.

[0018] In the figure, 1, inner ring; 2, outer ring; 3, ball; 4, oil seal ring; 5, main ring; 51, first outer ring; 511, abutment arc groove; 5111, guide groove; 512, first ring groove; 513, avoidance hole; 514, support frame; 515, first support plate; 516, first mounting plate; 5161, mounting hole; 52, first inner ring; 53, ring cavity; 54, heat dissipation hole; 55, insertion hole; 6, secondary ring; 61, second outer ring; 611, second support plate; 612, second mounting plate; 62, second inner ring; 621, second ring groove; 7, mounting assembly; 71, fixing rod; 72, snap structure. DETAILED DESCRIPTION

[0019] The following is combined with Figure 1-6 This application is described in further detail.

[0020] The embodiments of the present application disclose a ball bearing retainer and a bearing. Example 1

[0021] refer to Figure 1 and Figure 2 , the ball 3 bearing cage includes a main ring 5 and a secondary ring 6. The main ring 5 and the secondary ring 6 are arranged opposite to each other, and a first outer ring 51 and a first inner ring 52 are fixedly arranged on the side wall of the main ring 5 facing the secondary ring 6, wherein the diameter of the first outer ring 51 is greater than the diameter of the first inner ring 52. A second outer ring 61 and a second inner ring 62 are fixedly arranged on the side wall of the secondary ring 6 facing the main ring 5, wherein the second outer ring 61 is located opposite to the first outer ring 51, and the second inner ring 62 is located opposite to the first inner ring 52. The first outer ring 51 and the second inner ring 62 have the same length, and the first inner ring 52 and the second outer ring 61 have the same length, which is half of the first outer ring 51.

[0022] refer to Figure 2 and Figure 3 , the area enclosed by the main ring 5, the secondary ring 6, the first outer ring 51, the first inner ring 52, the second outer ring 61 and the second inner ring 62 is the annular cavity 53. A first annular groove 512 for the second outer ring 61 to extend into is provided on the side wall of the first outer ring 51 facing the annular cavity 53, which is away from the main ring 5. A second annular groove 621 for the first inner ring 52 to extend into is provided on the side wall of the second inner ring 62 facing the annular cavity 53, which is away from the secondary ring 6. A plurality of support frames 514 are fixed between the first inner ring 52 and the first outer ring 51. The support frames 514 can be tightly pressed against the first inner ring 52 and the second outer ring 61, and the ends of the support frames 514 are inclined excessively. The second outer ring 61 can be snapped into the first annular groove 512, and the first inner ring 52 can be snapped into the second annular groove 621. At this time, the end of the first outer ring 51 abuts against the secondary ring 6, and the end of the second inner ring 62 abuts against the main ring 5.

[0023] refer to Figure 2 and Figure 4The first inner ring 52 and the first outer ring 51 are both provided with abutment arc grooves 511 for abutting against the balls 3 at the same positions. The abutment arc grooves 511 are provided at one end of the main ring 5 away from the opening and are provided for the balls 3 to move from the opening to abut against the abutment arc grooves 511. The abutment arc grooves 511 are also provided at the same positions of the second inner ring 62 and the second outer ring 61. The abutment arc grooves 511 of the first outer ring 51 are provided with a guide groove 5111 inclined outwardly at a position of the abutment arc grooves 511 of the second inner ring 62 facing the second outer ring 61. The guide grooves 5111 are also provided at a position of the abutment arc grooves 511 of the second inner ring 62 facing the first inner ring 52. The inner wall of the contact arc groove 511 is in the shape of an arc convex shape, and the arc convex position of the contact arc groove 511 of the first outer ring 51 is opposite to the arc convex position of the contact arc groove 511 of the second outer ring 61; the arc convex position of the contact arc groove 511 of the second inner ring 62 is opposite to the arc convex position of the contact arc groove 511 of the first inner ring 52. The contact arc groove 511 of the first outer ring 51 is not connected to the contact arc groove 511 of the second outer ring 61, and the contact arc groove 511 of the first inner ring 52 is not connected to the contact arc groove 511 of the second inner ring 62. The ball 3 can contact the four contact arc grooves 511 at the same time, and the top and bottom of the ball 3 are exposed from the contact arc groove 511.

[0024] The main ring 5 and the secondary ring 6 are provided with fixing components for fixing the main ring 5 and the secondary ring 6 to each other.

[0025] The main ring 5 and the auxiliary ring 6 fix the ball 3 in the abutment arc groove 511 by interlocking. The ring cavity 53 structure formed by the first inner ring 52, the second inner ring 62, the second outer ring 61 and the second inner ring 62 reduces the contact area with the ball 3 on the one hand, and can also maintain stable abutment with the ball 3 through the abutment arc groove 511, thereby reducing friction heat generation while ensuring stable rotation of the ball 3. The arc surface position setting of the abutment arc groove 511 can make the abutment of the four abutment arc grooves 511 abutting against one ball 3 more stable and more balanced in force. The formed ring cavity 53 structure can also improve the heat dissipation effect.

[0026] The support frame 514 structure can not only provide stable structural support for the first inner ring 52 and the first outer ring 51, but also improve the stability of the second inner ring 62 and the second outer ring 61 by the inclined guide at the end, so that the second outer ring 61 can be stably clamped in the first ring groove 512, and the first inner ring 52 can be stably clamped in the second ring groove 621, thus realizing the pre-fixation of the main ring 5 and the auxiliary ring 6. Finally, the main ring 5 and the auxiliary ring 6 are finally fixed by the fixing assembly.

[0027] The frame structure on the main ring 5 and the secondary ring 6 not only improves the strength of the structure, but also reduces the material used and reduces the heat generated by the ball 3, making the ball 3 more stable and having a longer service life when rotating at high speed. The setting of the guide groove 5111 can also effectively improve the stability of the ball 3 moving into the abutment arc groove 511. When the main ring 5 and the secondary ring 6 are buckled together, the first outer ring 51 can abut against the secondary ring 6, and the second inner ring 62 can abut against the main ring 5, which improves the structural stability when buckled.

[0028] refer to Figure 2 and Figure 3 , the fixing assembly includes a fixing rod 71 and two buckle structures 72. The first outer ring 51, the first inner ring 52, the second outer ring 61 and the second inner ring 62 are all set as avoidance holes 513 at the positions between the abutting arc grooves 511, and the avoidance holes 513 are connected to the ring cavity 53. The side walls of the main ring 5 and the secondary ring 6 are provided with a plurality of heat dissipation holes 54 connected to the ring cavity 53. The structure of the avoidance holes 513 and the heat dissipation holes 54 can further improve the heat dissipation effect of the balls 3 on the retaining frame. The first inner ring 52 and the first outer ring 51 are fixedly provided with a first support plate 515 at a position close to the avoidance hole 513, and the two first support plates 515 on both sides of the avoidance hole 513 are fixedly provided with a first mounting plate 516. The second inner ring 62 and the second outer ring 61 are fixedly provided with a second support plate 611 at a position close to the avoidance hole 513, and the two second support plates 611 on both sides of the avoidance hole 513 are fixedly provided with a second mounting plate 612. The first mounting plate 516 and the second mounting plate 612 are both provided with relative mounting holes 5161, and the main ring 5 and the secondary ring 6 are provided with insertion holes 55 opposite to the mounting holes 5161, wherein the area of ​​the insertion holes 55 is larger than that of the mounting holes 5161, and both are for the fixing rods 71 ​​to pass through.

[0029] The fixing rod 71 is inserted into two opposite mounting holes 5161. The buckle structure 72 is elastic and V-shaped. It is fixed on the fixing rod 71, and one of the buckle structures 72 is located at the end of the fixing rod 71. The two buckle structures 72 are arranged opposite to each other, and the openings face opposite to each other. The fixing rod 71 and the buckle structure 72 are integrally formed, and can be made of plastic material or metal material. In this embodiment, the buckle structure 72 is made of polyvinyl chloride material. The inclined surface of the buckle structure 72 can abut against the mounting hole 5161 and pass through the mounting hole 5161. The buckle structure 72 is stretched after passing through the mounting hole 5161, and the ends of the two buckle structures 72 can abut against the first mounting plate 516 and the second mounting plate 612 and be tightened against each other.

[0030] The first support plate 515 and the second support plate 611 can effectively provide structural support for the first outer ring 51, the first inner ring 52, the second outer ring 61, and the second inner ring 62 at the avoidance hole 513, and also provide installation space for the installation plate, while not affecting the connection between the avoidance hole 513 and the ring cavity 53. After the main ring 5 and the secondary ring 6 are pre-fixed by buckling, the fixing rod 71 is inserted into the relative installation hole 5161, and the corresponding first installation plate 516 and second installation plate 612 are pressed against each other by the buckle structure 72, thereby achieving the final installation and fixation of the main ring 5 and the secondary ring 6, thereby improving the stability and installation efficiency of the main ring 5 and the secondary ring 6.

[0031] The implementation principle of the embodiment 1 of the present application is: the heat dissipation effect of the fixed ball 3 is improved by the ring cavity 53 formed by the structure of the main ring 5 and the auxiliary ring 6, and at the same time, the first outer ring 51, the first inner ring 52, the second outer ring 61 and the second inner ring 62 are matched with the arc groove 511 to achieve stable small-area abutment and fixation with the ball 3, so that the ball 3 can maintain stable rotation and reduce friction heat generation, which is more suitable for high-speed motion application scenarios. The structure of the support frame 514 can make the main board and the auxiliary ring 6 stable and fast pre-fixed and buckled, and then the main ring 5 and the auxiliary ring 6 are fixed by inserting the fixing rod 71, which improves the fixing efficiency and stability of the cage. Then, the high-speed stable rotation of the ball 3 and the effect of reducing heat generation are achieved through the new cage structure and the matched fixing method, and a lightweight design is achieved, which is suitable for assembly and use. Example 2

[0032] refer to Figure 5 and Figure 6 A ball bearing 3 includes the cage structure described in Example 1, and compared with Example 1, it also includes balls 3, inner ring 1, outer ring 2 and oil seal ring 4. The circumferential outer wall of the inner ring 1 and the circumferential inner wall of the outer ring 2 are both provided with arc grooves. There are multiple balls 3, which abut against the arc grooves of the inner ring 1 and the outer ring 2 so that the inner ring 1 is located in the middle of the outer ring 2. The cage positions the balls 3, that is, the balls 3 are clamped in the abutting arc grooves 511 through the guide grooves 5111. The oil seal ring 4 is installed between the inner ring 1 and the outer ring 2 to seal the cage therein.

[0033] The installation method of a ball 3 bearing in Example 2 of the present application is as follows: the inner ring 1 and the outer ring 2 are placed together on the installation platform, and the inner ring 1 is moved to a position abutting against the inner wall of the outer ring 2, and then a fixed number of balls 3 are placed between the inner ring 1 and the outer ring 2, and then the inner ring 1 is moved to the middle position of the outer ring 2, and the balls 3 are spread out. The main ring 5 is inserted upward from the bottom between the inner ring 1 and the outer ring 2, so that the balls 3 are stuck in the corresponding abutment arc groove 511. Then the secondary ring 6 is inserted from the top to realize the pre-fixation of the main ring 5 and the secondary ring 6, and then the fixing rod 71 is used to install and fix them. Finally, after lubrication, the oil seal ring 4 is installed on both sides of the inner ring 1 and the outer ring 2 to realize the installation of the ball 3 bearing, so that the ball 3 bearing is more stable and the heat generation is reduced when rotating at high speed.

[0034] The embodiments of this specific implementation method are all preferred embodiments of the present application, and are not intended to limit the protection scope of the present application. Therefore, all equivalent changes made based on the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A ball (3) bearing cage, comprising a main ring (5) and a secondary ring (6) that can be interlocked, wherein the main ring (5) and the secondary ring (6) are interlocked to position a plurality of balls (3), characterized in that: A first inner ring (52) and a first outer ring (51) are fixedly arranged on the side wall of the main ring (5) facing the secondary ring (6); the diameter of the first inner ring (52) is smaller than the diameter of the first outer ring (51); the first inner ring (52) and the first outer ring (51) are both provided with abutment arc grooves (511) for abutting against the balls (3) at the same positions; the abutment arc grooves (511) are arranged away from the opening at one end of the main ring (5) and are provided for the balls (3) to move from the opening to a position abutting against the abutment arc grooves (511); A second inner ring (62) and a second outer ring (61) are fixedly provided on the side wall of the secondary ring (6) facing the primary ring (5); the diameter of the second inner ring (62) is smaller than the diameter of the second outer ring (61); and the abutting arc groove (511) is also provided at the same position of the second inner ring (62) and the second outer ring (61); When the main ring (5) and the secondary ring (6) are locked together, the first inner ring (52) and the second inner ring (62) are locked together, and the first outer ring (51) and the second outer ring (61) are locked together, so that an annular cavity (53) is formed between the main ring (5) and the secondary ring (6). At this time, the contact arc grooves (511) of the first inner ring (52) and the second inner ring (62) are pressed against the bottom of the ball (3), and the contact arc grooves (511) of the first outer ring (51) and the second outer ring (61) are pressed against the top of the ball (3).

2. A ball (3) bearing cage and a bearing according to claim 1, characterized in that: The length of the first outer ring (51) is greater than the length of the first inner ring (52), and the length of the second inner ring (62) is greater than the length of the first inner ring (52); A first ring groove (512) is provided on the side wall of the first outer ring (51) facing the ring cavity (53) and is in contact with the second outer ring (61) and is used for the second outer ring (61) to be clamped therein; The second inner ring (62) is provided with a second annular groove (621) on the side wall facing the annular cavity (53), and the first inner ring (52) is clamped therein; A support frame (514) is fixedly provided between the first inner ring (52) and the first outer ring (51), and the support frame (514) can be tightly pressed against the first inner ring (52) and the second outer ring (61).

3. A ball (3) bearing cage and a bearing according to claim 2, characterized in that: The end of the support frame (514) is set to be tilted excessively.

4. A ball (3) bearing retainer and a bearing according to claim 2, characterized in that: An outwardly inclined guide groove (5111) is provided at a position of the abutting arc groove (511) of the first outer ring (51) facing the second outer ring (61), and the guide groove (5111) is also provided at a position of the abutting arc groove (511) of the second inner ring (62) facing the first inner ring (52).

5. A ball (3) bearing retainer and a bearing according to claim 2, characterized in that: The end of the first outer ring (51) can abut against the secondary ring (6), and the end of the second inner ring (62) can abut against the end of the main ring (5).

6. A ball (3) bearing retainer and a bearing according to claim 2, characterized in that: The positions of the first outer ring (51), the first inner ring (52), the second outer ring (61) and the second inner ring (62) between the abutting arc grooves (511) are all arranged to form avoidance holes (513), and the avoidance holes (513) are communicated with the annular cavity (53).

7. A ball (3) bearing cage and a bearing according to claim 6, characterized in that: The first inner ring (52) and the first outer ring (51) are fixedly provided with first support plates (515) at positions close to the avoidance hole (513), and the two first support plates (515) on both sides of the avoidance hole (513) are fixedly provided with first mounting plates (516); The second inner ring (62) and the second outer ring (61) are fixedly provided with a second support plate (611) at a position close to the avoidance hole (513), and the two second support plates (611) on both sides of the avoidance hole (513) are fixedly provided with a second mounting plate (612); The first mounting plate (516) and the second mounting plate (612) are both provided with mounting holes (5161) facing each other, and the main ring (5) and the secondary ring (6) are provided with insertion holes (55) facing the mounting holes (5161); The two mounting holes (5161) are inserted with a same fixing rod (71), and the fixing rod (71) is fixed with two sets of opposite buckle structures (72). The buckle structures (72) can be inserted through the mounting holes (5161) and then pop open, and the ends of the two buckle structures (72) can be pressed against the first mounting plate (516) and the second mounting plate (612) and tightened against each other.

8. A ball (3) bearing cage and a bearing according to claim 1, characterized in that: The main ring (5) and the auxiliary ring (6) are both provided with heat dissipation holes (54) which are in communication with the ring cavity (53) at intervals.

9. A ball (3) bearing cage and a bearing according to claim 1, characterized in that: The inner wall of the abutting arc groove (511) is in the shape of a circular arc protrusion.

10. A ball (3) bearing, comprising a retaining frame according to any one of claims 1 to 9, characterized in that: The invention also comprises balls (3), an inner ring (1), an outer ring (2) and an oil seal ring (4). The circumferential outer wall of the inner ring (1) and the circumferential inner wall of the outer ring (2) are both provided with arc grooves. There are a plurality of balls (3) which abut against the arc grooves of the inner ring (1) and the outer ring (2) so that the inner ring (1) is located in the middle of the outer ring (2). The retaining frame positions the balls (3). The oil seal ring (4) is installed between the inner ring (1) and the outer ring (2) to seal the retaining frame therein.

Images