A harmonic reducer bearing retainer

Abstract

The present application provides a harmonic reducer bearing cage, which belongs to the field of harmonic transmission flexible bearings, including an annular cage end ring, a plurality of window beams arranged at equal intervals along the circumference of the cage end ring, one end of the window beam is connected to the cage end ring, and an open pocket for accommodating a rolling body is formed between adjacent window beams, and the window beam is provided with a raised fin facing the outer ring surface, and the fins provided on the window beam enhance the structural strength of the window beam. When the cage is deformed by an external force, the fin can absorb part of the deformation energy through its own elastic deformation. Once the external force disappears, the elastic recovery ability of the fin can prompt the cage to quickly restore its original shape, reducing the risk of accumulated stress and fatigue fracture caused by continuous deformation, so that it can effectively resist the fatigue stress caused by continuous deformation during long-term operation. It helps to extend the service life of the cage and reduce failures and maintenance costs caused by fatigue fracture.

Description

Technical Field

[0001] The present application belongs to the field of harmonic drive flexible bearings, and in particular relates to a harmonic reducer bearing retainer. Background Art

[0002] Harmonic reducers use a wave generator to induce controllable elastic deformation in the flexspline, thereby meshing with the rigid wheel to transmit power and motion. This transmission method gives harmonic reducers advantages such as a high transmission ratio, compact size, low weight, high load capacity, smooth motion, no impact, and low noise. The wave generator of a harmonic reducer primarily consists of a flexible bearing and an elliptical cam. The wave generator is typically installed at the input end of the reducer. The inner ring of the flexible bearing is fixed to the cam, while the outer ring is elastically deformed into an elliptical shape using balls. When the wave generator is operating, its elliptical cam rotates within the flexspline, causing controllable elastic deformation of the flexspline and the bearing. This deformation causes the flexspline teeth to engage or disengage between the teeth of the rigid wheel during deformation, achieving power and motion transmission.

[0003] During operation, the inner ring of a flexible bearing is mounted on an elliptical rigid wheel, while the outer ring and the flexible wheel interact through sliding or rolling friction. To achieve power transmission and motion conversion, both the outer and inner rings of the bearing need to be able to deform elastically. In this structure, the retainers of the inner and outer rings must possess a certain degree of deformation capacity to accommodate the deformation of the flexible bearing during operation. Due to the unique operating principle of the harmonic reducer, the flexible bearing retainer undergoes repeated deformation and stress changes during operation. This repeated deformation can not only cause fatigue and fracture of the retainer material but also affect the precision of its fit with the bearing balls. During operation, insufficient retainer deformation often leads to premature failure of the flexible bearing, thus affecting the performance and stability of the entire reducer. To ensure the normal operation of the harmonic reducer and extend the service life of the flexible bearing retainer, targeted improvements and optimization of the harmonic reducer bearing retainer are necessary. Summary of the Invention

[0004] The present invention provides a harmonic reducer bearing retainer to at least solve or alleviate one or more technical problems in the prior art, or at least provide a beneficial option.

[0005] To achieve the above objectives, the present invention provides the following technical solutions:

[0006] A harmonic reducer bearing retainer is arranged between the outer ring and the inner ring of a flexible bearing, and includes an annular retainer end ring, and multiple window beams are arranged at equal intervals along the circumference of the retainer end ring. One end of the window beam is connected to the retainer end ring, and a first pocket for accommodating rolling elements is formed between adjacent window beams. The window beam is provided with a raised fin facing the outer ring surface, which is arranged inside the bearing to position the retainer to prevent it from moving. The fin has elastic deformation ability and can help the retainer restore its original shape when the retainer is deformed, so as to reduce the risk of accumulated stress and fatigue fracture of the retainer due to continuous deformation.

[0007] The harmonic reducer bearing cage of the present application has a window beam in the cage connected to an end ring at one end and a free end at the other end, allowing the window beam to have a certain degree of freedom when subjected to external forces, allowing it to undergo a certain degree of elastic deformation. This deformability helps the cage absorb and disperse the impact force through its own elastic deformation when subjected to impact or external forces, thereby reducing damage to the entire cage structure. The fins provided on the window beam not only enhance the structural strength of the window beam, but the tilted design of the fins brings them closer to the bearing outer ring, enabling them to better match the bearing outer ring and form a relatively fixed support structure. This support structure can effectively limit the range of movement of the cage within the bearing, preventing it from moving. Moreover, its elastic deformation ability plays an important role in the deformation of the cage. When the cage is deformed by external forces, the fins can absorb some of the deformation energy through their own elastic deformation. Once the external force disappears, the elastic recovery ability of the fins can prompt the cage to quickly return to its original shape, reducing the accumulated stress and fatigue fracture risk caused by continuous deformation, and enabling it to effectively resist the fatigue stress caused by continuous deformation during long-term operation. Helps extend cage life and reduce failures and maintenance costs due to fatigue fractures.

[0008] In a preferred implementation, the fin is rectangular, the width of the fin is the same as the width of the outer wall of the window beam, and the thickness of the fin is 1 / 10-1 / 6 of the thickness of the window beam.

[0009] The rectangular fin design is relatively simple and easy to manufacture and process, reducing manufacturing difficulty and cost while improving production efficiency. The fins are designed to be the same width as the outer wall of the window beam, ensuring a tight connection between the fins and the window beam, enhancing the stability and integrity of the entire structure. The fin thickness is 1 / 10-1 / 6 of the window beam thickness. This proportional design ensures sufficient elastic deformation capacity while avoiding excessive material waste.

[0010] In a preferred implementation, a second pocket is provided at the free end of the fin, and a ball is mounted in the second pocket. The ball can contact the outer ring raceway to reduce the contact friction between the fin and the outer ring.

[0011] By arranging a rolling ball at the free end of the fin, when the free end of the fin abuts against the inner wall of the outer ring, the ball can form rolling contact between the fin and the inner wall of the outer ring, thereby significantly reducing the friction generated by the contact.

[0012] In a preferred implementation, the outer wall surface of the window beam is provided with a pair of fins that are symmetrical relative to the height center of the window beam.

[0013] In a preferred implementation, outer wall surfaces of adjacent window beams are provided with fins that are symmetrically offset relative to the height center of the window beam.

[0014] In a preferred implementation, an angle θ is formed between the fin and the outer wall of the window beam, satisfying 0°<θ≤15°.

[0015] When the angle θ is in the range of 0°<θ≤15°, the fin is guaranteed to have sufficient elastic deformation capacity, and the fin occupies less space in the cage, which helps to reduce the overall size of the cage and realize the compact design of the reducer. When the angle θ is greater than 15°, the connection between the fin and the window beam may become a stress concentration area, increasing the risk of local deformation and damage. At the same time, an excessively large angle θ means that the fin needs to occupy more space, which may cause the overall size of the cage to increase, which is not conducive to the compact design of the reducer.

[0016] In a preferred implementation, the free end of the fin extends to the plane where the end ring of the retainer is located.

[0017] The free ends of the fins extend to the plane of the cage end rings, which not only enhances the continuity of the structure, but also optimizes the stress transfer path within the cage. When subjected to external force, the stress can be more smoothly transferred through the fins to the end rings and then dispersed to the entire cage structure, helping to reduce stress concentration and reduce the risk of deformation and damage caused by local high stress.

[0018] In a preferred implementation, an oil-retaining gap is formed between the fin and the outer wall surface of the window beam.

[0019] The presence of the oil gap allows the lubricating oil to be better distributed between the fins and the outer wall of the window beam. The oil gap helps to improve the heat dissipation performance of the cage. The lubricating oil can more effectively remove heat through the oil gap and reduce the temperature of the cage.

[0020] In a preferred implementation, the window beam and the fin are integrally formed by injection molding.

[0021] In a preferred implementation, the window beam and the fin are detachably connected. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present application and do not constitute an improper limitation of the present invention. In the drawings:

[0023] Figure 1 A three-dimensional structural view of a schematic embodiment of a bearing retainer of a harmonic reducer of the present application is depicted;

[0024] Figure 2 A schematic structural view of a fin of the present application is depicted;

[0025] Figure 3 A front view of a schematic embodiment of a bearing retainer of a harmonic reducer of the present application is depicted;

[0026] Description of labels:

[0027] 1-cage end ring; 2-window beam; 3-first pocket; 4-fin; 40-second pocket; 5-angle; 6-oil gap; 7-rolling element; 8-ball. DETAILED DESCRIPTION

[0028] Hereinafter, only certain exemplary embodiments are briefly described. As will be appreciated by those skilled in the art, the described embodiments may be modified in various ways without departing from the spirit and scope of the present invention. Therefore, the drawings and description are to be considered as illustrative in nature and not restrictive.

[0029] The present invention will be described below with reference to the accompanying drawings.

[0030] The specific plans adopted are:

[0031] like Figure 1-3 As shown, the present invention provides a harmonic reducer bearing retainer, which is arranged between the outer ring and the inner ring of the flexible bearing, including an annular retainer end ring 1, and a plurality of window beams 2 are arranged at equal intervals along the circumference of the retainer end ring 1, one end of the window beam 2 is connected to the retainer end ring 1, and a first pocket 3 for accommodating a rolling body 7 is formed between adjacent window beams 2, and the window beam 2 is provided with a raised fin 4 facing the outer ring surface, which is arranged inside the bearing to position the retainer to prevent it from moving. The fin 4 has elastic deformation ability and can help the retainer restore its original shape when the retainer is deformed, so as to reduce the risk of accumulated stress and fatigue fracture of the retainer due to continuous deformation.

[0032] The harmonic reducer bearing cage of the present application has a window beam 2 in the cage connected to an end ring at one end and a free end at the other end, so that the window beam 2 has a certain degree of freedom when subjected to external force, and can undergo a certain elastic deformation. This deformation ability helps the cage absorb and disperse the impact force through its own elastic deformation when subjected to impact or external force, thereby reducing damage to the entire cage structure. The fins 4 provided on the window beam 2 not only enhance the structural strength of the window beam 2, but also play an important role in the deformation of the cage. When the cage is deformed by external force, the fins 4 can absorb part of the deformation energy through their own elastic deformation. Once the external force disappears, the elastic recovery ability of the fins 4 can prompt the cage to quickly return to its original shape, reducing the risk of accumulated stress and fatigue fracture caused by continuous deformation, and enabling it to effectively resist the fatigue stress caused by continuous deformation during long-term operation. This helps to extend the service life of the cage and reduce the failure and maintenance costs caused by fatigue fracture.

[0033] As a preferred embodiment of the present application, the fin 4 is rectangular, the width of the fin 4 is the same as the width of the outer wall of the window beam 2, and the thickness of the fin 4 accounts for 1 / 10-1 / 6 of the thickness of the window beam 2.

[0034] The design of the rectangular fin 4 is relatively simple and easy to manufacture and process, so as to reduce the difficulty and cost of manufacturing and improve production efficiency. The design of the fin 4 having the same width as the outer wall of the window beam 2 ensures a close connection between the fin 4 and the window beam 2, thereby enhancing the stability and integrity of the entire structure. The thickness of the fin 4 accounts for 1 / 10-1 / 6 of the thickness of the window beam 2. Such a proportional design ensures that the fin 4 has sufficient elastic deformation capacity while avoiding excessive waste of material. Due to the moderate thickness of the fin 4, it can undergo a certain degree of elastic deformation when subjected to external force, absorbing and dispersing the impact force. At the same time, the fin 4 can also quickly return to its original shape after deformation, which helps to reduce the risk of accumulated stress and fatigue fracture caused by continuous deformation of the retaining frame.

[0035] As a preferred embodiment of the present application, a second pocket 40 is provided at the free end of the fin 4. The second pocket 40 is used to mount a ball 8. The ball 8 can contact the outer ring raceway to reduce the contact friction between the fin 4 and the outer ring.

[0036] By placing rolling balls 8 at the free ends of the fins 4, when the free ends of the fins 4 abut the inner wall of the outer ring, the balls 8 form rolling contact between the fins 4 and the inner wall of the outer ring, significantly reducing the friction caused by contact. When the cage deforms, the rolling characteristics of the balls 8 mitigate the resulting contact pressure, reducing the increase in friction caused by deformation. This makes the system more tolerant to cage deformation, improving overall reliability and stability.

[0037] Furthermore, when both ball 8 and the rolling elements 7 of the window beam 2 contact the outer raceway and slide, they share the load applied to the bearing, compared to when only ball 8 slides on the outer raceway. This load distribution helps reduce the pressure at a single point of contact, thereby reducing the wear rate of the contact area. When only ball 8 slides, ball 8 may experience higher local pressure, accelerating wear. When multiple rolling elements 7 (ball 8 and rolling elements 7 of the window beam 2) slide simultaneously, the vibration and impact forces applied to the bearing are reduced, thereby reducing fatigue damage caused by dynamic stress and extending the bearing's service life.

[0038] The distribution of the fins 4 on the window beam 2 can be one of the following embodiments:

[0039] In embodiment 1, the outer wall surface of the window beam 2 is provided with a pair of fins 4 which are symmetrical with respect to the height center of the window beam 2 .

[0040] When the outer wall surface of the window beam 2 is provided with a pair of fins 4 that are highly centrally symmetrical relative to the window beam 2, it helps to improve the structural strength and stability of the window beam 2, and can also better disperse the external load. The centrally symmetrical fin 4 design enables the window beam 2 to maintain balance when subjected to stress, reducing the stress concentration phenomenon caused by uneven stress. This helps to enhance the load-bearing capacity of the window beam 2 and improve its fatigue resistance. In addition, when combined with the rolling body 7 of the retaining frame window beam 2, the balls 8 and the rolling body 7 work together to further reduce friction and wear, and improve the operating efficiency of the entire system. The symmetrical presence of the balls 8 can also play a supporting and guiding role, allowing the rolling body 7 to maintain a stable trajectory during movement. The use of the symmetrical fin 4 structure and the balls 8 allows the window beam 2 to maintain balance and stability when subjected to stress, thereby improving the reliability and durability of the entire retaining frame.

[0041] Embodiment 2: The outer wall surfaces of adjacent window beams 2 are provided with fins 4 that are symmetrically offset relative to the height center of the window beams 2 .

[0042] The staggered symmetrical fin 4 design can make the window beam 2 better disperse and balance the load when subjected to external force. This design helps to reduce stress concentration, improve the bearing capacity of the window beam 2, thereby extending its service life. The ball 8 at the free end of the fin 4 can effectively reduce the friction between the fin 4 and the outer wall surface, making the window beam 2 smoother when moving. This rolling friction not only reduces energy consumption, but also reduces wear and tear, thereby improving the efficiency of the system. Due to the combined effect of the ball 8 and the fin 4, the window beam 2 can maintain better stability when subjected to external force, reduce shaking and vibration, and improve the stability of the overall structure. Compared with the solution of Example 1, the staggered symmetrical fin 4 design can reduce unnecessary material use while ensuring mechanical properties. By rationally designing the shape and size of the fin 4, it is possible to achieve maximum utilization of materials and reduce processing costs while meeting structural requirements.

[0043] As a preferred embodiment of the present application, an angle 5θ is formed between the fin 4 and the outer wall surface of the window beam 2 , satisfying 0°<θ≤15°.

[0044] The existence of angle 5 makes the space occupied by fin 4 in the cage smaller, which helps to reduce the overall size of the cage and realize the compact design of the reducer. For thin-walled bearings, a compact cage design means smaller bearing clearance, which helps to improve the supporting performance and stability of the bearing. Angle 5 that is too large may cause the structural stability of the cage to decrease. When subjected to external force, an excessively large angle 5 may cause the connection between the fin 4 and the window beam 2 to become an area of ​​stress concentration, increasing the risk of local deformation and damage. At the same time, an excessively large angle 5 means that the fin 4 needs to occupy more space, which may cause the overall size of the cage to increase, which is not conducive to the compact design of the reducer. At the same time, a larger angle 5 may also lead to a decrease in material utilization, increasing manufacturing costs.

[0045] As a preferred embodiment of the present application, the free end of the fin 4 extends to the plane where the retainer end ring 1 is located.

[0046] The free end of the fin 4 extends to the plane where the retainer end ring 1 is located, which actually connects the window beam 2 and the retainer end ring 1 more tightly, not only enhancing the continuity of the structure, but also optimizing the stress transfer path within the retainer. When subjected to external force, the stress can be more smoothly transferred to the end ring through the fin 4, and then dispersed to the entire retainer structure, which helps to reduce stress concentration and reduce the risk of deformation and damage caused by local high stress.

[0047] As a preferred embodiment of the present application, an oil gap 6 is formed between the fin 4 and the outer wall surface of the window beam 2 .

[0048] The presence of the oil gap 6 allows the lubricating oil to be better distributed between the fins 4 and the outer wall of the window beam 2. The oil gap 6 helps improve the heat dissipation performance of the cage. The lubricating oil can more effectively remove heat through the oil gap 6, reducing the temperature of the cage and preventing performance degradation or damage due to overheating. The lubricating effect of the lubricating oil makes the contact between the fins 4 and the outer wall of the window beam 2 smoother, reducing vibration caused by friction. At the same time, the flow of lubricating oil also absorbs some noise, making the speed reducer run more smoothly and quietly.

[0049] As a preferred embodiment of the present application, the window beam 2 and the fin 4 are integrally formed by injection molding.

[0050] Through one-piece injection molding, an integral connection is formed between the window beam 2 and the fin 4, ensuring the overall structural strength and stability of the retaining frame, so that it can better resist deformation when subjected to external forces. At the same time, one-piece injection molding production can also improve production efficiency and reduce production costs.

[0051] As a preferred embodiment of the present application, the window beam 2 and the fin 4 are detachably connected.

[0052] Because the window beam 2 and fins 4 are removable, such as with bolts and clips, when the fins 4 or window beam 2 become worn, damaged, or require upgrading, the components can be replaced individually without having to replace the entire window beam 2 or the system. This greatly simplifies the maintenance process, reduces maintenance costs, and improves the maintainability of the system. When the fins 4 or window beam 2 need to be replaced due to wear or damage, the removable design allows only the damaged components to be replaced, thereby reducing the consumption of new materials and conforming to the concepts of environmental protection and sustainable development.

[0053] Anything not described in the present invention can be achieved by adopting or drawing on existing technologies.

[0054] The above are merely specific embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art can easily conceive of various modifications or substitutions within the technical scope disclosed in the present invention, and such modifications or substitutions are intended to be within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be subject to the scope of protection of the claims.

Claims

1. A harmonic reducer bearing retainer, arranged between the outer ring and the inner ring of a flexible bearing, characterized in that: It includes an annular retainer end ring, and multiple window beams are arranged at equal intervals along the circumference of the retainer end ring. One end of the window beam is connected to the retainer end ring, and a first pocket for accommodating rolling bodies is formed between adjacent window beams. The window beam is provided with a raised fin facing the outer ring surface, which is arranged inside the bearing to position the retainer to prevent it from moving. The fin has elastic deformation ability, absorbs part of the deformation energy through its own elastic deformation, and can help the retainer to restore its original shape when the retainer is deformed, so as to reduce the risk of accumulated stress and fatigue fracture of the retainer due to continuous deformation. The width of the fin is the same as the width of the outer wall of the window beam. The free end of the fin is provided with a second pocket, and a ball is installed in the second pocket. The ball can contact with the outer ring raceway to reduce the contact friction between the fin and the outer ring.

2. The harmonic reducer bearing holder according to claim 1, characterized in that: The fin is rectangular, and the thickness of the fin accounts for 1 / 10-1 / 6 of the thickness of the window beam.

3. The harmonic reducer bearing holder according to claim 1, characterized in that: The outer wall surface of the window beam is provided with a pair of fins which are symmetrical with respect to the height center of the window beam.

4. The harmonic reducer bearing holder according to claim 1, characterized in that: The outer wall surfaces of the adjacent window beams are provided with fins which are symmetrically offset relative to the height center of the window beam.

5. The harmonic reducer bearing holder according to claim 1, characterized in that: There is an angle θ between the fin and the outer wall of the window beam, which satisfies 0°<θ≤15°.

6. The harmonic reducer bearing holder according to claim 1, characterized in that: The free end of the fin extends to the plane where the end ring of the retainer is located.

7. The harmonic reducer bearing holder according to claim 1, characterized in that: An oil-retaining gap is formed between the fin and the outer wall surface of the window beam.

8. The harmonic reducer bearing holder according to claim 1, characterized in that: The window beam and the fin are integrally formed by injection molding.

9. The harmonic reducer bearing holder according to claim 1, characterized in that: The window beam and the fin are detachably connected.

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