Injection-molded one-piece cylindrical roller bearing cage and bearing assembly

Abstract

This application provides a molded integrated cylindrical roller bearing cage and bearing assembly, belonging to the field of bearing technology. The molded integrated cylindrical roller bearing cage includes: an annular cage; and a pocket formed on the annular cage for holding the roller body. The inner wall of the pocket has a first protrusion and a second protrusion for positioning the roller body. The inner surface of the first protrusion is arc-shaped, and the inner surface of the second protrusion is flat. A locking point for positioning the roller body is formed at the connection between the first and second protrusions. The molded integrated cylindrical roller bearing cage provided in this application, by optimizing the locking point structure inside the pocket, balances the convenience of roller assembly and the positioning stability during operation while ensuring the injection molding processability.

Description

Technical Field

[0001] This application belongs to the field of bearing technology, specifically relating to an injection-molded integral cylindrical roller bearing cage and bearing assembly. Background Technology

[0002] Cylindrical roller bearings are widely used in rolling mills, wind power, and heavy-duty machinery transmissions due to their excellent radial load capacity and high limiting speed.

[0003] Traditional cylindrical roller bearing cages are mostly made of brass or stamped steel. Although the structure is simple, under high-speed operation or heavy load conditions, the coefficient of friction between the metal cage and the rollers is relatively high, and the lack of self-lubrication ability can easily lead to excessive temperature rise and accelerated wear. Furthermore, traditional brass cages are prone to damage to the raceway surface when assembling rollers. The force required to press the rollers into the brass cage is large, and the impact between the rollers and the raceway at the moment of pressing can easily cause damage. Summary of the Invention

[0004] To address at least one of the technical problems existing in the background art, this application provides an injection-molded integral cylindrical roller bearing cage, which optimizes the locking point structure inside the pocket, ensuring the injection molding process while taking into account the convenience of roller assembly and the positioning stability during operation.

[0005] A second aspect of this application provides a bearing assembly.

[0006] The technical solution adopted in this application is as follows: The first aspect of this application provides a molded integral cylindrical roller bearing cage, comprising: Circular cage; A pocket, formed on the annular retainer, is used to hold the roller body; The inner wall of the pocket is provided with a first protrusion and a second protrusion for positioning the roller body. The inner side of the first protrusion is arc-shaped, and the inner side of the second protrusion is flat. A locking point for positioning the roller body is formed at the connection between the first protrusion and the second protrusion.

[0007] According to the first aspect of the embodiment of this application, the injection-molded integral cylindrical roller bearing cage solves the dual problems of assembly damage in traditional metal cages and unstable positioning in existing injection-molded cages by providing a first protrusion and a second protrusion with an arc surface and a flat surface respectively on the inner wall of the pocket, and using the connection point of the two to form a locking point. Its working principle is that the arc-shaped first protrusion can conform to the curvature of the roller body for close support, which not only reduces frictional resistance during relative movement, but also the flat second protrusion acts as a limiting structure, utilizing the elastic deformation capability of the injection molding material to provide guidance and buffering during the pressing process of the roller body, avoiding the raceway damage problem caused by rigid extrusion in traditional brass cages; the flat second protrusion also acts as a limiting structure, effectively preventing the roller body from moving under load, and preventing plastic deformation or fracture of the cage pocket due to stress concentration. The locking point structure formed at the connection between the two, through precise control of the interference fit (0.1mm to 1mm) and the locking point length (accounting for 40%-50% of the roller length), ensures the smooth press-fit of the roller body while providing a reliable positioning reference for the roller body during bearing operation. This avoids impact or guide failure of the cage beam column caused by radial displacement of the roller body, and significantly improves the running stability and service life of the bearing assembly.

[0008] According to one embodiment of this application, a window beam is formed between two adjacent pockets; A groove is formed at the transition surface between the first protrusion and the window beam, so that the first protrusion forms a cantilever structure at the groove.

[0009] According to one embodiment of this application, the width of the first protrusion is greater than the width of the second protrusion.

[0010] According to one embodiment of this application, the length of the locking point accounts for 40% to 50% of the total length of the roller body.

[0011] According to one embodiment of this application, the interference between the locking point and the roller body is 0.1 mm to 1 mm.

[0012] According to one embodiment of this application, the extending directions of the first protrusion and the second protrusion are parallel to the axial direction of the roller body; In the extending direction, the inner wall of the pocket is provided with at least two sets of spaced-apart first protrusions and second protrusions.

[0013] According to one embodiment of this application, the distance between the end faces of the first protrusion and the second protrusion and the end face of the annular retainer is not less than 10 mm.

[0014] According to one embodiment of this application, the distance between two adjacent groups of the first protrusion and the second protrusion is 10 mm to 12 mm.

[0015] A second aspect of this application provides a bearing assembly, including: The roller body; and, As described above, in any embodiment of the first aspect, the injection-molded integral cylindrical roller bearing cage has the roller body disposed within the pocket of the injection-molded integral cylindrical roller bearing cage.

[0016] According to one embodiment of this application, it also includes: An inner ring and an outer ring, wherein the inner ring is coaxially disposed within the outer ring, and an annular raceway is formed between the outer circumferential surface of the inner ring and the inner circumferential surface of the outer ring; The roller body and the injection-molded integral cylindrical roller bearing cage are disposed within the annular raceway. Attached Figure Description

[0017] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings: Figure 1 A schematic diagram of the structure of the injection-molded integral cylindrical roller bearing cage provided in an embodiment of this application; Figure 2 for Figure 1 A magnified schematic diagram of point A of the injection-molded integral cylindrical roller bearing cage shown; Figure 3 This is a schematic diagram of the bearing assembly provided in an embodiment of this application; Figure 4 This is a schematic diagram of the internal structure of the bearing assembly provided in an embodiment of this application.

[0018] in, 11. Circular retainer; 12. Pocket; 13. First protrusion; 14. Second protrusion; 15. Locking point; 16. Window beam; 17. Groove; 2. Bearing assembly; 21. Roller body; 22. Inner ring; 23. Outer ring. Detailed Implementation

[0019] To more clearly illustrate the overall concept of this application, a detailed explanation is provided below with reference to the accompanying drawings.

[0020] Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application may also be implemented in other ways different from those described herein. Therefore, the scope of protection of this application is not limited to the specific embodiments disclosed below. It should be noted that, unless otherwise specified, the embodiments of this application and the features thereof can be combined with each other.

[0021] Furthermore, it should be understood in the description of this application that the terms "top", "bottom", "inner", "outer", "axial", "radial", "circumferential", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0022] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a communication connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0023] In this application, unless otherwise expressly specified and limited, the "above" or "below" of the second feature can mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. In the description of this specification, references to terms such as "an embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described can be combined in any suitable manner in one or more embodiments or examples.

[0024] like Figures 1 to 2 As shown, a first aspect embodiment of this application provides a molded integral cylindrical roller bearing cage, comprising: Circular retainer 11; A pocket 12 is formed on the annular retainer 11 for holding the roller body 21; The inner wall of the pocket 12 is provided with a first protrusion 13 and a second protrusion 14 for positioning the roller body 21. The inner surface of the first protrusion 13 is arc-shaped, and the inner surface of the second protrusion 14 is flat. A locking point 15 for positioning the roller body 21 is formed at the connection between the first protrusion 13 and the second protrusion 14.

[0025] The injection-molded integrated cylindrical roller bearing cage mainly consists of an annular cage 11 and pockets 12 evenly distributed thereon, used to accommodate and guide the movement of the roller body 21. By providing a first protrusion 13 with an arcuate inner surface and a second protrusion 14 with a planar inner surface, and connecting the two to form a locking point 15, the arcuate structure achieves close support with the roller, and the planar structure provides limiting and blocking, thereby constructing a positioning mechanism that combines guiding and locking functions inside the pockets 12.

[0026] According to the first aspect of the embodiment of this application, the injection-molded integral cylindrical roller bearing cage solves the dual problems of assembly damage in traditional metal cages and unstable positioning in existing injection-molded cages by providing a first protrusion 13 and a second protrusion 14 with curved and flat inner surfaces respectively on the inner wall of the pocket 12, and forming a locking point 15 at the connection between the two. Its working principle is that the curved first protrusion 13 can conform to the curvature of the roller body 21 for support, reducing frictional resistance during relative movement. The flat second protrusion 14 acts as a limiting structure, utilizing the elastic deformation capability of the injection molding material to provide guidance and buffering during the pressing process of the roller body 21, avoiding the raceway damage problem caused by rigid extrusion in traditional brass cages. The flat second protrusion 14 also acts as a limiting structure, effectively preventing the roller body 21 from shifting under load, preventing plastic deformation or fracture of the cage pocket 12 due to stress concentration. The locking point 15 structure formed at the connection between the two, through precise control of the interference (0.1mm to 1mm) and the length of the locking point 15 (accounting for 40%-50% of the roller length), ensures the smooth press-fit of the roller body 21, while providing a reliable positioning reference for the roller body 21 during bearing operation. This avoids impact or guide failure of the cage beam column caused by radial displacement of the roller body 21, and significantly improves the running stability and service life of the bearing assembly 2.

[0027] like Figures 1 to 2 As shown, in some embodiments of this application, a window beam 16 is formed between two adjacent pockets 12; A groove 17 is formed at the transition surface between the first protrusion 13 and the window beam 16, so that the first protrusion 13 forms a cantilever structure at the groove 17.

[0028] A window beam 16 is provided between two adjacent pockets 12 as a supporting skeleton for the retainer. A groove 17 is provided at the transition surface between the first protrusion 13 and the window beam 16. This groove 17 separates the end of the first protrusion 13, forming a cantilever structure. The cantilever structure has high flexibility. From the perspective of mold design and demolding process, the groove 17 can eliminate the risk of "backlash" caused by the geometry of the first protrusion 13 during injection molding, allowing the mold core to be extracted smoothly without the need for complex sliders or inclined ejector mechanisms. This simplifies the mold structure and reduces manufacturing costs. At the same time, this design reduces the clamping area and frictional resistance during demolding, avoiding appearance defects such as tearing or whitening of the retainer due to stress concentration during ejection. This ensures the surface quality of the product and improves the stability and yield of demolding.

[0029] In some embodiments of this application, the width of the first protrusion 13 is greater than the width of the second protrusion 14. The first protrusion 13, as the main radial support surface, significantly increases the contact area with the roller body 21, effectively dispersing the radial load generated by the bearing under high-speed rotation or heavy-load conditions, reducing local stress concentration, and thus improving the cage's resistance to deformation and fatigue life. The second protrusion 14 primarily serves a lateral positioning function; its narrower width design ensures effective blocking of the roller body 21 while avoiding injection molding shrinkage marks or increased internal stress caused by excessive material accumulation.

[0030] In terms of assembly, this wide-narrow matching structure makes the locking point 15 area form a "flexible transition" shape. The wide first protrusion 13 provides a stable support base, while the narrow second protrusion 14 is more likely to generate elastic deformation when the roller is pressed, which makes it easier for the roller to pass smoothly through the locking point 15 and be embedded in the pocket 12. This ensures both the convenience of assembly and the reliability of positioning in the working state.

[0031] In some embodiments of this application, the length of the locking point 15 accounts for 40% to 50% of the total length of the roller body 21.

[0032] Locking point 15 is a key part that restricts the lateral movement of the roller body 21. Its length directly determines the cage's ability to constrain the roller body 21. If the length of locking point 15 is too short (less than 40%), the contact area between locking point 15 and roller body 21 will be insufficient when the bearing is subjected to a large impact load. This can easily lead to excessive local stress and crush the injection molding material, causing damage to the cage or the roller body 21 to come off. If the length of locking point 15 is too long (greater than 50%), although the lateral positioning ability is enhanced, it will lead to an increase in the contact stroke of the roller body 21 during press-fitting, and the assembly resistance will rise sharply. This not only increases the assembly difficulty, but also makes it easy for the injection molding material to soften or wear due to frictional heat during press-fitting. By controlling the length of locking point 15 within the range of 40% to 50% of the total length of the roller, it is possible to ensure that when the bearing is running at high speed or under load, locking point 15 has sufficient support area to effectively limit the lateral displacement of the roller body 21 and prevent cage guide failure caused by the movement of the roller body 21. It is also possible to ensure that the roller body 21 can be smoothly inserted into the pocket 12 with a reasonable pressing force during assembly, avoiding cage deformation or roller surface damage caused by excessive assembly force.

[0033] In some embodiments of this application, the interference fit between the locking point 15 and the roller body 21 is 0.1 mm to 1 mm.

[0034] The interference fit directly determines the lateral locking force of the locking point 15 on the roller body 21 and the elastic deformation capability of the cage. If the interference fit is too small (below 0.1mm), the locking point 15 cannot provide sufficient lateral clamping force when the bearing is subjected to vibration or impact, which can easily lead to fretting wear or lateral movement of the roller body 21, and thus cause cage guide failure. Conversely, if the interference fit is too large (above 1mm), the roller body 21 will force the cage to produce excessive elastic deformation during the press-fit process, resulting in high residual stress inside the injection molding material, which can easily induce stress cracking or creep under long-term operation. Therefore, strictly controlling the interference fit within the range of 0.1mm to 1mm can ensure smooth press-fitting of the roller body 21 while utilizing the elastic recovery force of the injection molding material to achieve reliable "self-locking", and can also effectively avoid excessive assembly stress, significantly improving the operational stability and service life of the bearing assembly 2.

[0035] For example, 0.5 mm is selected as the interference between the locking point 15 and the roller body 21. Considering that the injection molding material has a certain elastic modulus, at the moment the roller body 21 is pressed in, the interference of 0.5 mm is sufficient to force the first protrusion 13 and the second protrusion 14 of the cage to produce controllable elastic deformation, so that the roller body 21 can smoothly pass through the locking point 15 and be inserted into the pocket 12, without causing excessive assembly stress due to excessive interference, thereby avoiding the risk of cracking or creep failure of the cage due to excessive residual stress.

[0036] In some embodiments of this application, the extending directions of the first protrusion 13 and the second protrusion 14 are parallel to the axial direction of the roller body 21. In the extending direction, the inner wall of the pocket 12 is provided with at least two sets of spaced-apart first protrusions 13 and second protrusions 14.

[0037] When a single set of protrusions is subjected to radial load, torque imbalance is likely to occur, causing the roller body 21 to tilt or wear unevenly within the pocket 12. However, when two or more sets of protrusions are arranged axially at intervals, they form a stable multi-point support system, which can evenly distribute the radial and lateral combined loads when the roller body 21 is in operation, effectively suppress the deflection tendency of the roller body 21, and ensure that the roller body 21 is always in a precise positioning state.

[0038] In practical applications, the synergistic effect of multiple locking points 15 significantly improves the fit stiffness between the cage pocket 12 and the roller body 21. Even when the bearing is subjected to severe vibration or impact loads, it can prevent abnormal wear or jamming between the roller body 21 and the cage, thereby significantly improving the operating accuracy and reliability of the bearing assembly 2.

[0039] In some embodiments of this application, the distance between the end faces of the first protrusion 13 and the second protrusion 14 and the end face of the annular cage 11 is not less than 10 mm. As a key part that directly bears the force of the roller body 21, the transition area between the end face of the protrusion and the end face of the cage body (i.e., the bottom rounded corner of the pocket 12) is a sensitive area for stress concentration. If the distance is too small, the radial pressure applied by the roller body 21 to the protrusion during assembly will be directly transmitted to the bottom rounded corner of the pocket 12, resulting in excessive local stress in this area, which is very likely to cause material yielding or fatigue cracks. Setting the distance to not less than 10 mm is equivalent to forming a sufficiently long "stress buffer zone" between the protrusion and the cage body, which can effectively disperse and transmit the load, avoid excessive stress concentration at the rounded corner of the pocket 12, and thus significantly reduce the risk of structural failure during assembly and operation.

[0040] In some embodiments of this application, the distance between two adjacent sets of first protrusions 13 and second protrusions 14 is 10 mm to 12 mm. This distance directly affects the force distribution of the multi-point support structure: if the distance is too small, the wall of the pocket 12 between adjacent protrusions will become too rigid due to material accumulation, resulting in a decrease in the elastic deformation capacity of the roller body 21 during press-fitting, an increase in assembly resistance, and a tendency to produce shrinkage defects during injection molding; if the distance is too large, it will weaken the constraint capacity on the roller body 21, causing the roller body 21 to be prone to tilting or uneven wear during operation.

[0041] By strictly controlling the spacing within the range of 10mm to 12mm, it is possible to ensure that there is a sufficient elastic deformation area between adjacent protrusions, so that the roller body 21 can pass smoothly through the locking point 15 and be embedded in the pocket 12 during press fitting. It is also possible to ensure that multiple sets of protrusions can work together to evenly distribute the radial load during bearing operation, effectively suppressing the tendency of the roller body 21 to move and deflect.

[0042] like Figures 3 to 4 As shown, a second aspect embodiment of this application provides a bearing assembly 2, comprising: Roller body 21; and, In any embodiment of the first aspect described above, the roller body 21 of the injection-molded integral cylindrical roller bearing cage is disposed within the pocket 12 of the injection-molded integral cylindrical roller bearing cage.

[0043] The bearing assembly 2 is assembled from a roller body 21 and the injection-molded integral cylindrical roller bearing cage of the first aspect embodiment. The roller body 21 is housed within the pocket 12 of the cage, and positioning is achieved through a locking point 15 structure formed by the first protrusion 13 and the second protrusion 14 on the inner wall of the pocket 12. Utilizing the elastic properties of the injection-molded cage material, combined with an interference fit design of 0.1mm to 1mm at the locking point 15, the roller body 21 is reliably locked by the restoring force generated by elastic deformation while ensuring smooth press-fitting. Compared to traditional metal cages, this assembly effectively avoids the risk of damage during assembly, and the distributed support structure of multiple sets of protrusions (spacing 10mm to 12mm) significantly improves the smoothness of the roller body 21's operation.

[0044] like Figure 3 As shown, in some embodiments of this application, it further includes: Inner ring 22 and outer ring 23, the inner ring 22 is coaxially disposed inside the outer ring 23, and an annular raceway is formed between the outer peripheral surface of the inner ring 22 and the inner peripheral surface of the outer ring 23; The roller body 21 and the injection-molded integral cylindrical roller bearing cage are arranged in the annular raceway.

[0045] The inner ring 22 and outer ring 23 are coaxially arranged, and their mating raceway surfaces together form an annular raceway space that accommodates the roller body 21 and the injection-molded cage. Combined with the aforementioned injection-molded cage featuring an optimized locking point 15 structure, this assembly effectively prevents the roller body 21 from damaging the raceway during assembly, and maintains stable guidance of the roller body 21 during operation thanks to the elasticity and multi-point support characteristics of the cage. The annular raceway structure not only provides a reliable protective environment for the internal rolling elements but also eliminates stress concentration caused by installation errors through precise geometric fit. This results in a longer service life and higher operational reliability under complex operating conditions involving heavy loads, high speeds, and impacts, making it particularly suitable for rolling mills, wind power systems, and heavy machinery transmission systems with stringent stability requirements.

[0046] For any parts not mentioned in this application, existing technologies may be used or referenced.

[0047] The various embodiments in this specification are described in a progressive manner. The same or similar parts between the various embodiments can be referred to each other. Each embodiment focuses on describing the differences from other embodiments.

[0048] The above description is merely an embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A one-piece injection-molded cylindrical roller bearing cage, characterized in that, include: Circular retainer (11); A pocket (12) is formed on the annular retainer (11) for holding the roller body (21). The inner wall of the pocket (12) is provided with a first protrusion (13) and a second protrusion (14) for positioning the roller body (21). The inner surface of the first protrusion (13) is arc-shaped, and the inner surface of the second protrusion (14) is flat. A locking point (15) for positioning the roller body (21) is formed at the connection between the first protrusion (13) and the second protrusion (14).

2. The injection-molded integral cylindrical roller bearing cage according to claim 1, characterized in that, A window beam (16) is formed between two adjacent pockets (12); A groove (17) is formed at the transition surface between the first protrusion (13) and the window beam (16), so that the first protrusion (13) forms a cantilever structure at the groove (17).

3. The injection-molded integrated cylindrical roller bearing cage according to claim 1, characterized in that, The width of the first protrusion (13) is greater than the width of the second protrusion (14).

4. The injection-molded integrated cylindrical roller bearing cage according to claim 1, characterized in that, The length of the locking point (15) accounts for 40% to 50% of the total length of the roller body (21).

5. The injection-molded integral cylindrical roller bearing cage according to claim 1, characterized in that, The interference fit between the locking point (15) and the roller body (21) is 0.1 mm to 1 mm.

6. The injection-molded integrated cylindrical roller bearing cage according to claim 1, characterized in that, The extension directions of the first protrusion (13) and the second protrusion (14) are parallel to the axial direction of the roller body (21); In the extending direction, the inner wall of the pocket (12) is provided with at least two sets of spaced-apart first protrusions (13) and second protrusions (14).

7. The injection-molded integral cylindrical roller bearing cage according to claim 1, characterized in that, The distance between the end faces of the first protrusion (13) and the second protrusion (14) and the end face of the annular retainer (11) is not less than 10 mm.

8. The injection-molded integral cylindrical roller bearing cage according to claim 6, characterized in that, The distance between two adjacent sets of the first protrusion (13) and the second protrusion (14) is 10 mm to 12 mm.

9. A bearing assembly (2), characterized in that, include: Roller body (21); and, The injection-molded integral cylindrical roller bearing cage as described in any one of claims 1 to 8, wherein the roller body (21) is disposed within the pocket (12) of the injection-molded integral cylindrical roller bearing cage.

10. The bearing assembly (2) according to claim 9, characterized in that, Also includes: Inner ring (22) and outer ring (23), wherein the inner ring (22) is coaxially disposed within the outer ring (23), and an annular raceway is formed between the outer circumferential surface of the inner ring (22) and the inner circumferential surface of the outer ring (23); The roller body (21) and the injection-molded integral cylindrical roller bearing cage are disposed within the annular raceway.

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