A novel harmonic reducer retainer

Abstract

The application discloses a novel harmonic reducer retainer which is composed of two end rings and a plurality of window beams which are connected to the two end rings and are uniformly distributed along a circumference, the window beams are provided with through holes which penetrate from one side of the window beams facing an inner ring to the other side of the window beams facing an outer ring, the opposite sides of the two end rings are provided with notches, the two ends of the through holes extend to the notches of the two end rings, and elastic recovery members are arranged in the through holes, when the end rings are deformed, the elastic recovery members in the through holes and the notches are deformed to accumulate elastic potential energy, in the process of restoring the circular shape of the retainer, the elastic recovery members release the potential energy and apply auxiliary recovery force to the end rings in the opposite direction of the deformation direction, compared with the traditional retainer in which the end rings rely on their own elastic recovery, the auxiliary recovery force of the application can make the end rings reset faster, reduce residual deformation, reduce fatigue damage of the end rings, and greatly improve the fatigue life of the retainer under high-frequency deformation.

Description

Technical Field

[0001] This application belongs to the field of harmonic reducer cages, and particularly relates to a novel harmonic reducer cage. Background Technology

[0002] As a core component of the robot joint transmission system, the cage of the harmonic reducer has the core function of ensuring the normal operation of each component by precisely controlling the spatial position of the rollers. With the trend of miniaturization of robot joints, the cage needs to meet extreme size constraints. Taking the dexterous hand of a humanoid robot as an example, the cage used in this device has a diameter of only about 10mm and a wall thickness of about 0.3mm, yet it may need to withstand thousands of elliptical deformation cycles per minute. This operating condition requires the cage to simultaneously possess lightweight, high elastic modulus (ensuring rapid recovery of the original shape after deformation), and fatigue resistance (maintaining structural integrity after deformation cycles). Currently, the above-mentioned characteristics of the cage are mostly improved by modifying the materials used in its manufacture, and significant results have been achieved. However, the cost is high. Existing cages for harmonic reducers are still mainly based on traditional structures such as crown-shaped and cylindrical shapes. In miniaturized scenarios, high-frequency deformation of these structures leads to rapid performance degradation of the cage and makes it prone to excessive cracks at the connection points. Therefore, it is urgent to break through the existing technical bottlenecks through structural innovation and develop a harmonic reducer cage that combines lightweight, high elastic modulus, and long fatigue life to meet the dual performance and cost requirements of high-end equipment such as humanoid robots for joint transmission systems. Utility Model Content

[0003] This invention provides a novel cage for harmonic reducers, which solves the problem of rapid decay of elastic performance of cages for miniature harmonic reducers under high-frequency deformation.

[0004] To achieve the above objectives, the present invention provides the following technical solution:

[0005] A novel harmonic reducer cage comprises two end rings and multiple window beams evenly distributed along the circumference, connecting the two end rings. Each window beam has a through hole extending from the inner side of the window beam to the outer side. The opposite faces of the two end rings have notches, and the two ends of the through hole extend to these notches. An elastic recovery element is installed inside the through hole. When the cage undergoes periodic elliptical deformation, the elastic recovery element deforms and accumulates elastic potential energy. During the cage's recovery process, the elastic recovery element applies an auxiliary restoring force to the end rings, thereby reducing fatigue damage to the end rings and extending the overall service life of the cage.

[0006] The novel harmonic reducer cage of this application, when the end ring deforms, causes the elastic recovery components in the through hole and notch to deform, thereby accumulating elastic potential energy. During the process of the cage returning to its circular shape, the elastic recovery components release potential energy and apply an auxiliary restoring force to the end ring in the opposite direction of deformation. Compared with the pure elastic recovery of the end ring itself, the additional auxiliary restoring force will enable the end ring to reset faster, reduce residual deformation, and thus reduce fatigue damage to the end ring. This can greatly improve the fatigue life of the cage under high-frequency deformation, and at the same time, greatly improve the elastic recovery efficiency, meeting the high service life requirements of high-end equipment such as humanoid robot dexterous hands.

[0007] In the preferred implementation, the two ends of the elastic recovery member are connected to the two opposite inner walls of the through hole in the circumferential direction, and the upper and lower ends extend to the end ring notch and leave a gap space between them and the upper and lower end rings.

[0008] In a preferred implementation, the elastic recovery element is arc-shaped and the radius of curvature of the arc-shaped elastic recovery element is smaller than the radius of curvature of the two end rings.

[0009] In a preferred embodiment, two arc-shaped elastic recovery members are provided inside the through hole, and the openings of the two arc-shaped elastic recovery members are arranged opposite to each other or in the same direction.

[0010] In the preferred implementation, the elastic recovery element is wavy.

[0011] In a preferred implementation, one or more elastic recovery elements are provided inside the through hole.

[0012] In a preferred embodiment, the end ring includes a large-diameter end ring and a small-diameter end ring with the same ring width. The radial thickness of the window beam is greater than that of the large-diameter end ring / small-diameter end ring. Both ends of the window beam include a high part and a low part, forming a stepped surface between them. The large-diameter end ring and the small-diameter end ring are connected to the stepped surface, and the high part abuts against the sidewalls of the large-diameter end ring and the small-diameter end ring.

[0013] In the preferred implementation, the outer ring wall of the large-diameter end ring is flush with the outer side of the window beam, and the inner ring wall of the small-diameter end ring is flush with the inner side of the window beam. The two high parts respectively abut against the outer ring wall of the small-diameter end ring and the inner ring wall of the large-diameter end ring.

[0014] In a preferred implementation, the side of the higher part that is in contact with the other side is a circular arc segment with two openings in opposite directions, and the two circular arc segments are smoothly and continuously transitioned.

[0015] In a preferred embodiment, the window beam, end ring, and elastic recovery component are integrally formed. Attached Figure Description

[0016] The accompanying drawings, which are included to provide a further understanding of the present invention and constitute a part of this invention, illustrate exemplary embodiments of the present invention and, together with the description thereof, serve to explain this application and do not constitute an undue limitation of the present invention. In the drawings:

[0017] Figure 1 A schematic three-dimensional structural diagram of one embodiment of the cage of the novel harmonic reducer of this application is shown;

[0018] Figure 2 A schematic perspective view of another embodiment of the cage of the novel harmonic reducer of this application is shown in the diagram.

[0019] Figure 3 A schematic cross-sectional view of one embodiment of the cage of the novel harmonic reducer of this application is shown.

[0020] Label Explanation:

[0021] 1. End ring; 10. Large diameter end ring; 11. Small diameter end ring; 12. Notched groove; 2. Window beam; 20. High part; 21. Low part; 22. Through hole; 3. Elastic recovery part; 30. Gap space. Detailed Implementation

[0022] In the following description, only certain exemplary embodiments are briefly described. As those skilled in the art will recognize, the described embodiments can be modified in various ways without departing from the spirit and scope of this invention. Therefore, the drawings and description are considered exemplary in nature and not restrictive.

[0023] In the description of this utility model, it should be understood that the terms "center," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "axial," "radial," and "circumferential," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model 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 utility model. In this utility model, unless otherwise expressly specified and limited, the first feature being "upper" or "lower" than 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.

[0024] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral unit; 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. However, specifying a direct connection indicates that the two main bodies at the connection point are not connected by an intermediate structure, but are simply connected to form a whole through a connecting structure. For those skilled in the art, the specific meaning of the above terms in this utility model can be understood according to the specific circumstances.

[0025] In this utility model, descriptions involving "first," "second," etc., are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature.

[0026] The present invention will now be described with reference to the accompanying drawings.

[0027] The specific solution adopted is as follows:

[0028] like Figure 1-3 As shown, this utility model provides a novel harmonic reducer cage, which consists of two end rings 1 and multiple window beams 2 that connect the two end rings and are evenly distributed along the circumference. The window beams are provided with through holes, which extend from the side of the window beam facing the inner ring to the side of the window beam facing the outer ring. The opposite sides of the two end rings are provided with notches, and the two ends of the through holes extend to the notches 12 of the two end rings. An elastic recovery member 3 is provided inside the through hole 22. When the cage undergoes periodic elliptical deformation, the elastic recovery member will deform and accumulate elastic potential energy. During the process of the cage restoring its shape, the elastic recovery member will apply an auxiliary restoring force to the end rings, thereby reducing fatigue damage to the end rings and improving the overall service life of the cage.

[0029] The novel harmonic reducer cage of this application, when the end ring deforms, causes the through hole 22 and the elastic recovery element 3 in the notch to deform, thereby accumulating elastic potential energy. During the process of the cage returning to a circular shape, the elastic recovery element releases potential energy and applies an auxiliary recovery force to the end ring in the opposite direction of deformation. Compared with the pure elastic recovery of the end ring itself, the additional auxiliary recovery force will enable the end ring to reset faster, reduce residual deformation, and thus reduce fatigue damage to the end ring. This can greatly improve the fatigue life of the cage under high-frequency deformation, and at the same time greatly improve the elastic recovery efficiency, meeting the high service life requirements of high-end equipment such as humanoid robot dexterous hands.

[0030] Traditional cages with non-through-hole window beams, when the cage undergoes periodic deformation, such as the long shaft, the compressive force on the rolling elements is directly transmitted to the outer ring. Under high-frequency alternating loads, this can easily lead to surface pitting (fatigue spalling). However, the window beams of this application have increased flexibility. The window beam portions on both sides of the through-hole can deform slightly in the direction of the through-hole when compressed by the rolling elements, thereby reducing rigid compressive force and lowering the probability of pitting.

[0031] In a preferred embodiment of this application, the elastic recovery member 3 is connected to the two opposing inner walls of the through hole at both ends in the circumferential direction, and extends to the end ring notch at both ends, leaving a gap space 30 between it and the upper and lower end rings. The gap space not only constitutes a micro oil channel, but also allows the elastic recovery member to undergo greater elastic deformation than the end ring, thereby generating a greater restoring force. If there is no gap at both ends and it is connected to the end ring, its deformation will be restricted by the end ring.

[0032] In addition, one or more elastic recovery elements are installed inside the through hole. The synergistic effect of the elastic recovery elements can significantly enhance the auxiliary restoring force on the support frame.

[0033] Furthermore, the elastic recovery element is arc-shaped, and the radius of curvature of the arc-shaped elastic recovery element is smaller than the radius of curvature of the two end rings.

[0034] When the cage undergoes periodic elliptical deformation, the elastic recovery element, with its smaller radius of curvature, will produce a greater degree of bending deformation under the same external force. This greater deformation allows the elastic recovery element to store more elastic potential energy. When the cage returns to its original shape, the stored elastic potential energy is rapidly released, providing a stronger auxiliary restoring force to the support frame. This significantly enhances the overall elastic recovery capability of the cage, ensuring it can quickly and accurately return to its initial shape and maintain the stable operation of the robot's joint transmission system.

[0035] See Figure 3 In this embodiment, two arc-shaped elastic recovery members are provided in the through hole. The openings of the two arc-shaped elastic recovery members are opposite or in the same direction. While ensuring the recovery force, the weight of the cage is reduced as much as possible, thus achieving lightweighting.

[0036] In another preferred embodiment of this application, the elastic recovery member 3 may also be wavy. The wavy structure consists of multiple continuous arc-shaped peaks and troughs, and each wave segment can be regarded as an independent elastic unit. When the support frame deforms, each wave segment enters the elastic deformation stage. During the local recovery stage of the cage, the wavy elastic recovery member can also provide auxiliary recovery force to help the end ring recover, improve the elastic recovery performance of the cage, and thus extend the fatigue life.

[0037] See Figure 1The end rings include a large-diameter end ring 10 and a small-diameter end ring 11 with the same ring width. The radial thickness of the window beam is greater than that of the large-diameter end ring / small-diameter end ring. Both ends of the window beam include a high part 20 and a low part 21, forming a stepped surface between them. The large-diameter end ring and the small-diameter end ring are connected to the stepped surface, and the high part abuts against the sidewalls of the large-diameter end ring and the small-diameter end ring. In the arrangement of the large-diameter end ring and the small-diameter end ring, the small-diameter end ring and the large-diameter end ring have different degrees of deformation when subjected to the same force. The deformation of the small-diameter end ring is greater than that of the large-diameter end ring. Therefore, in the recovery stage, it can assist the large-diameter end ring in recovery. Even if it experiences fatigue fracture first, the large-diameter end ring remains intact, and the retainer can still perform its function.

[0038] The stepped surface connection increases the contact area and connection strength between the end ring and the window beam. The higher section uses a lateral abutment method for the two end rings, rather than directly applying force at the connection point of the traditional end ring and window beam. This effectively reduces the risk of stress fracture at the connection point in traditional structures and extends the service life of the support frame. In the traditional connection structure between the window beam and the end ring, the connection point is a critical area of ​​stress concentration. When subjected to external forces, stress will rapidly concentrate at the connection point, easily leading to material fatigue and fracture.

[0039] In this design, the lateral contact between the high part of the window beam and the sidewall of the end ring, along with the stepped surface connection, increases the contact area and connection strength between the end ring and the window beam, thus dispersing and optimizing the stress transfer path. The lateral contact ensures that stress is evenly distributed along the sidewall of the end ring, avoiding stress concentration at the connection point and reducing the possibility of fracture due to excessive stress at the connection.

[0040] Furthermore, the outer ring wall of the large-diameter end ring is flush with the outer side of the window beam, and the inner ring wall of the small-diameter end ring is flush with the inner side of the window beam. This arrangement helps to further disperse stress, improve the overall stress resistance of the structure, reduce the cage thickness, and is suitable for use inside miniature bearings.

[0041] In a preferred embodiment of this application, the side of the high part that is in contact with the other side is a circular arc segment with two openings in opposite directions. The two circular arc segments are smoothly and continuously transitioned. If a right angle or sharp angle is used for the transition, the geometric change will lead to local stress concentration. The smooth and continuous transition of the two circular arc segments in this application makes the stress evenly distributed along the arc length, and the local maximum stress is greatly reduced compared to a right angle.

[0042] In a preferred embodiment of this application, the window beam, end ring, and elastic recovery component are integrally molded. This integral molding process (injection molding) completely eliminates the connection interface, improving the structural load-bearing capacity. The deformation energy of the elastic recovery component can be directly distributed and transferred through the continuous connection between the window beam and the end ring, reducing costs while meeting the high reliability and long lifespan requirements of high-end fields such as aerospace and robotics.

[0043] For any parts not mentioned in this utility model, existing technologies can be used or referenced.

[0044] The above are merely specific embodiments of this utility model, but the protection scope of this utility model is not limited thereto. Any person skilled in the art can easily conceive of various variations or substitutions within the technical scope disclosed in this utility model, and these should all be included within the protection scope of this utility model. Therefore, the protection scope of this utility model should be determined by the scope of the claims.

Claims

1. A novel harmonic reducer cage, comprising two end rings and multiple window beams connecting the two end rings and evenly distributed along the circumference, characterized in that, A through hole is provided on the window beam, extending from the inner side of the window beam to the outer side. The two end rings have notches on their opposite sides, and the two ends of the through hole extend to the notches of the end rings. An elastic recovery element is provided inside the through hole. When the cage undergoes periodic elliptical deformation, the elastic recovery element will deform and accumulate elastic potential energy. During the process of the cage restoring its shape, the elastic recovery element will apply an auxiliary restoring force to the end rings, thereby reducing fatigue damage to the end rings and improving the overall service life of the cage.

2. The novel harmonic reducer cage according to claim 1, characterized in that, The elastic recovery component is connected to the two opposite inner walls of the through hole at both ends in the circumferential direction, and extends to the end ring notch at both ends with a gap space between it and the upper and lower end rings.

3. The novel harmonic reducer cage according to claim 2, characterized in that, The elastic recovery element is arc-shaped, and the radius of curvature of the arc-shaped elastic recovery element is smaller than the radius of curvature of the rings at both ends.

4. The novel harmonic reducer cage according to claim 3, characterized in that, Two arc-shaped elastic recovery elements are installed inside the through hole, with the openings of the two arc-shaped elastic recovery elements facing each other or in the same direction.

5. The novel harmonic reducer cage according to claim 2, characterized in that, The elastic recovery element is wavy.

6. The novel harmonic reducer cage according to claim 1, characterized in that, One or more elastic recovery elements are installed inside the through hole.

7. The novel harmonic reducer cage according to claim 1, characterized in that, The end rings include a large-diameter end ring and a small-diameter end ring with the same ring width. The radial thickness of the window beam is greater than that of the large-diameter end ring / small-diameter end ring. Both ends of the window beam include a high part and a low part, forming a stepped surface between them. The large-diameter end ring and the small-diameter end ring are connected to the stepped surface, and the high part abuts against the sidewalls of the large-diameter end ring and the small-diameter end ring.

8. The novel harmonic reducer cage according to claim 7, characterized in that, The outer ring wall of the large-diameter end ring is flush with the outer side of the window beam, and the inner ring wall of the small-diameter end ring is flush with the inner side of the window beam. The high parts on both sides abut against the outer ring wall of the small-diameter end ring and the inner ring wall of the large-diameter end ring, respectively.

9. The novel harmonic reducer cage according to claim 7, characterized in that, The side of the upper part that is in contact with each other consists of two arc segments with opposite openings, and the two arc segments are smoothly and continuously transitioned.

10. The novel harmonic reducer cage according to claim 1, characterized in that, The window beam, end ring, and elastic recovery component are integrally formed.

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