Curvature transition type flexible gear
By designing a curvature transition type flexible wheel and using a semi-circular transition area and rounded corner transition connection, the stress concentration problem of the flexible wheel is solved, thereby improving the service life and load-bearing capacity of the flexible wheel.
Patent Information
- Application Number
- CN202520559751.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-27
- Publication Date
- 2026-02-06
- Estimated Expiration
- 2035-03-27
AI Technical Summary
Flexible gears are easily damaged in harmonic reducers, especially in the gear ring and cylinder bottom area where stress is concentrated, leading to material fatigue and failure.
The design incorporates a curvature transition type flexible wheel, which reduces stress concentration and optimizes the structural layout by introducing a semi-circular transition area at the bottom of the cylinder and rounded transition connections between the horizontal extension section and the vertical section.
It improves the fatigue life and stability of the flexible wheel, reduces the risk of material fatigue and failure, and enhances the load-bearing capacity.
Smart Images
Figure CN223881663U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The application belongs to the field of harmonic reducer flexspline, and particularly relates to a curvature transition type flexspline. BACKGROUND
[0002] The harmonic reducer is widely applied in many fields due to its compact structure, small volume, high transmission precision, large transmission ratio, strong bearing capacity and high transmission efficiency. The reducer mainly comprises a wave generator, a flexspline and a rigid wheel, wherein the flexspline as a core working component directly determines the service life of the entire harmonic reducer. However, the flexspline is more vulnerable to damage than other components in the actual operation process, and therefore, improving the fatigue life of the flexspline becomes a key problem in the design of the harmonic reducer.
[0003] At present, the main failure points of the flexspline are concentrated in the gear ring area and the bottom area, which are also the places where the flexspline bears a large equivalent stress. The right-angle connection design of the flexspline cylinder and the bottom (flange) can not effectively disperse the stress when the flexspline is periodically deformed under the extrusion of the wave generator, although a round corner transition is adopted at the intersection. In the deformation process of the flexspline, the round corner area will be subjected to a large extrusion and stretching action, thereby causing stress concentration. In view of this problem, designing a new type of flexspline, adjusting the structural layout of the key parts and eliminating the stress concentration area have become important improvement directions for optimizing the structure of the flexspline and improving its performance. CONTENT OF THE UTILITY MODEL
[0004] The utility model provides a curvature transition type flexspline, and a new type of flexspline is designed and the structural layout of the key parts is adjusted to eliminate the stress concentration area of the flexspline.
[0005] To achieve the above object, the utility model provides the following technical scheme:
[0006] A curvature transition type flexspline comprises a cylinder with a gear ring and a flange plate at the bottom of the cylinder, the bottom of the cylinder has a semicircular transition area curved towards the inside of the cylinder, the semicircular transition area is connected with a horizontal extension section, the horizontal extension section is connected with a vertical section in turn, the vertical section is connected with the flange plate, the semicircular transition area and the horizontal extension section absorb and disperse the deformation energy, thereby reducing the stress directly transmitted to the vertical section and reducing the stress concentration phenomenon at the connection between the cylinder and the flange plate.
[0007] The above structure, the bottom of the barrel is designed as a semicircular transition area curved towards the inside of the barrel, which provides a larger radius and smooth transition path, helping to disperse stress during deformation. The semicircular transition area is followed by a horizontal extension, which is connected to a vertical section, which is finally connected to the flange, further extending the stress transfer path and reducing stress concentration at a particular point. The entire barrel structure of the flexible gear is connected through continuous curvature changes, avoiding abrupt points, improving the overall structure and continuity, and reducing material fatigue and failure caused by stress concentration.
[0008] In a preferred implementation, the semicircular transition area has a first fillet transition area with the horizontal extension.
[0009] The presence of the first fillet transition area makes the connection between the semicircular transition area and the horizontal extension smoother, avoiding stress concentration caused by abrupt points. This smooth transition helps to disperse and transfer stress during the deformation of the flexible gear, reducing the risk of material damage caused by stress concentration.
[0010] In a preferred implementation, the horizontal extension has a second fillet transition area with the vertical section.
[0011] The presence of the second fillet transition area further reduces stress concentration at the connection between the horizontal extension and the vertical section.
[0012] In a preferred implementation, the vertical section has a third fillet transition area with the flange.
[0013] In a preferred implementation, there is a gap between the semicircular transition area and the flange, avoiding direct contact between the flexible gear and the flange during deformation.
[0014] Avoiding direct contact between the semicircular transition area and the flange during deformation of the flexible gear prevents wear and performance degradation caused by it.
[0015] In a preferred implementation, the radius r of the semicircular transition area satisfies 5mm≤r≤10mm.
[0016] In a preferred implementation, the ring gear includes a plurality of evenly spaced teeth, and the top surface of the teeth is planar.
[0017] When the gear is under load during operation, evenly distributed teeth can more effectively disperse stress and avoid excessive local stress, thereby reducing the risk of fatigue fracture of the teeth due to stress concentration. The design of the planar top surface of the teeth helps to reduce friction and wear between the teeth.
[0018] In the preferred implementation, the tooth body is provided with a first slope near the upper end of the barrel body and a second slope at the other end, and the slope of the second slope is smaller than that of the first slope.
[0019] In the preferred implementation, the tooth body comprises a fitting tooth part and an extension tooth part, and the fitting tooth part and the extension tooth part are connected by the second slope.
[0020] In the preferred implementation, the extension tooth part is gradually enlarged in tooth width from the end connected to the second slope to the other end. BRIEF DESCRIPTION OF DRAWINGS
[0021] The drawings described herein are used to provide further understanding of the present application, and form a part of the present application. The illustrative embodiments of the present application and their description serve to explain the present application. They do not constitute an improper limitation on the present application. In the drawings:
[0022] Figure 1 A cross-sectional structure schematic view of one illustrative embodiment of the curvature transition type flexspline of the present application is shown;
[0023] Figure 2 An enlarged structure schematic view of one illustrative embodiment of part A of the present application is shown; Figure 1
[0024] Figure 3 An enlarged structure schematic view of one illustrative embodiment of the tooth body of the present application is shown.
[0025] LIST OF REFERENCES:
[0026] 1, barrel body; 10, gear ring; 100, tooth body; 1001, fitting tooth part; 1002, extension tooth part; 1003, first slope; 1004, second slope; 11, semicircular transition area; 12, first round corner transition area; 13, horizontal extension section; 14, second round corner transition area; 15, vertical section; 16, third round corner transition area; 2, flange. DETAILED DESCRIPTION
[0027] In the following, only certain illustrative embodiments are simply described. As those skilled in the art can recognize, the described embodiments can be modified in various different ways without departing from the spirit and scope of the present application. Therefore, the drawings and the description are considered to be exemplary rather than limiting.
[0028] In the description of the utility model, it is understood that the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "axial", "radial", "circumferential" and the like indicate the orientation or positional relationship shown in the drawings, which is only for the convenience of describing the utility model and simplifying the description, and does not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the utility model. In the utility model, unless otherwise explicitly specified and limited, the first feature is "on" or "under" the second feature, which can be direct contact between the first and second features, or indirect contact between the first and second features through an intermediate medium.
[0029] In the utility model, unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connection", "fixing" and the like should be understood broadly, for example, it can be fixed connection, or detachable connection, or integrated; it can be directly connected, or indirectly connected through an intermediate medium, or it can be the internal communication of two elements or the interaction relationship of two elements. However, it is pointed out that direct connection means that the connection between the two main bodies does not form a connection relationship through excessive structure, but is connected to form a whole only through the connecting structure. For ordinary skilled persons in the art, the specific meaning of the above terms in the utility model can be understood according to the specific situation.
[0030] In the utility model, the description of "first", "second" and the like is only for the purpose of description, and cannot be understood as indicating or implying the relative importance of the indicated technical features or implicitly indicating the number of the indicated technical features. Therefore, the features limited by "first", "second" can explicitly or implicitly include at least one of the features.
[0031] The utility model will be described below in conjunction with the drawings of the specification.
[0032] The specific scheme adopted is:
[0033] As shown in Figures 1-3 The utility model provides a curvature transition type flexible gear, including the cylinder 1 with gear ring 10 and the flange plate 2 of cylinder 1 bottom, the bottom of cylinder 1 has the semicircular transition area 11 bending towards the inside of cylinder 1, the semicircular transition area 11 is immediately followed by a horizontal extension section 13, the horizontal extension section 13 is in turn connected to a vertical section 15, the vertical section 15 is connected with the flange plate 2, the semicircular transition area 11 and the horizontal extension section 13 absorb and disperse deformation energy, thereby reducing the stress directly transmitted to the vertical section 15, reducing the stress concentration phenomenon at the connection of cylinder 1 and flange plate 2.
[0034] The curvature transition type flexible gear of the present application, the bottom of the barrel 1 is designed as a semicircular transition area 11 curved towards the inside of the barrel 1, which replaces the traditional right angle design and sets a fillet connection at the intersection, the semicircular transition area 11 provides a larger fillet diameter and a smooth transition path, which helps to disperse stress during deformation. The semicircular transition area 11 is followed by a horizontal extension section 13, which is connected to a vertical section 15, which is finally connected to the flange plate 2, further extending the stress transmission path and reducing the stress concentration at a certain point. The entire barrel bottom structure of the flexible gear is connected through continuous curvature change, avoiding sudden change points, improving the overall structure and continuity, and reducing material fatigue and failure caused by stress concentration.
[0035] As a preferred embodiment of the present application, the semicircular transition area 11 has a first fillet transition area 12 with the horizontal extension section 13.
[0036] The existence of the first fillet transition area makes the connection between the semicircular transition area 11 and the horizontal extension section 13 smoother, avoiding stress concentration caused by sudden change points. This smooth transition helps to disperse and transmit stress during the deformation of the flexible gear, reducing the risk of material damage caused by stress concentration. By reasonably designing the radius of the first fillet transition area, the stress distribution inside the flexible gear can be further optimized, so that it can be more evenly distributed on the entire structure when subjected to extrusion by the wave generator, thereby improving the carrying capacity and stability of the flexible gear.
[0037] Further, the horizontal extension section 13 has a second fillet transition area 14 with the vertical section 15. The existence of the second fillet transition area further reduces the stress concentration phenomenon at the connection between the horizontal extension section 13 and the vertical section 15. During the deformation of the flexible gear, this fillet transition area can absorb and disperse part of the stress, thereby reducing the stress size directly transmitted to the vertical section 15. By reasonably designing the radius of the second fillet transition area, the stress distribution inside the flexible gear can be further optimized.
[0038] In addition, the vertical section 15 has a third fillet transition area 16 with the flange plate 2.
[0039] In the design of the curvature transition type flexspline, a third fillet transition region is designed between the vertical section 15 and the flange plate 2, which together with the aforementioned semicircular transition region 11, the first fillet transition region and the second fillet transition region forms a continuous and smooth curvature transition system of the flexspline structure. Starting from the semicircular transition region 11 at the bottom of the cylinder 1, the first fillet transition region connects the horizontally extending section 13, the second fillet transition region connects the vertical section 15, and finally the third fillet transition region smoothly transitions to the flange plate 2. This continuous and smooth transition system ensures the stability and reliability of the flexspline during deformation. The design of multiple fillet transition regions provides a longer transmission path and more dispersion points for stress. This helps to optimize stress distribution, allowing stress to be more evenly distributed throughout the flexspline structure, thereby improving its load-carrying capacity and stability.
[0040] As a preferred embodiment of the present application, there is a gap between the semicircular transition region 11 and the flange plate 2, avoiding direct contact between the flexspline and the flange plate 2 during deformation. Considering the elliptical motion of the flexspline during periodic deformation, a reasonable gap is set between the semicircular transition region 11 and the flange plate 2 to avoid direct contact between the semicircular transition region 11 and the flange plate 2 during deformation, thereby preventing wear and performance degradation caused thereby.
[0041] As a preferred embodiment of the present application, the radius r of the semicircular transition region 11 satisfies 5mm≤r≤10mm. When the radius r is in the range of 5mm to 10mm, the transition region can provide a smooth transition, reducing the risk of cracks or damage caused by stress concentration. By optimizing stress distribution, the semicircular transition region 11 can enhance the load-carrying capacity of the structure, allowing it to withstand greater loads without failure.
[0042] As a preferred embodiment of the present application, the ring gear 10 includes a plurality of uniformly spaced tooth bodies 100, and the top surface of the tooth body 100 is a plane. The design of uniformly spaced tooth bodies 100 helps to make the tooth surface stress distribution more uniform. When the gear is under load during operation, the uniformly distributed tooth bodies 100 can more effectively disperse stress, avoiding excessive local stress, thereby reducing the risk of fatigue fracture of the tooth body 100 due to stress concentration. The design of the tooth body 100 with a flat top surface helps to reduce friction and wear between the tooth surfaces. During gear operation, the contact area between the tooth surfaces is relatively large and uniform, which helps to disperse friction and wear, prolonging the service life of the tooth body 100.
[0043] As a preferred embodiment of the present application, the tooth body 100 is provided with a first inclined surface 1003 near the upper end of the barrel 1 and a second inclined surface 1004 at the other end, the slope of the second inclined surface 1004 is smaller than that of the first inclined surface 1003, the tooth body 100 includes a matching tooth part 1001 and an extended tooth part 1002, the matching tooth part 1001 and the extended tooth part 1002 are connected through the second inclined surface 1004, and the tooth width of the extended tooth part 1002 gradually increases from the end connected to the second inclined surface 1004 to the other end.
[0044] The design of the first inclined surface 1003 and the second inclined surface 1004 enables the tooth body 100 to gradually disperse stress along the inclined surface when bearing stress. Due to the existence of the inclined surface, stress will not be concentrated on a certain point, but will be gradually transmitted and dispersed along the inclined surface. The slope of the second inclined surface 1004 is smaller than that of the first inclined surface 1003, which can further disperse stress. When stress is transmitted to the second inclined surface 1004, due to the reduction of the slope, stress will be more evenly distributed on the tooth body 100, avoiding excessive local stress. The tooth width of the extended tooth part 1002 gradually increases from the end connected to the second inclined surface 1004 to the other end, enhancing the anti-deformation ability of the tooth body 100. When stress is transmitted to the extended tooth part 1002, due to the gradual increase of the tooth width, the tooth body 100 can better resist deformation, thereby maintaining the overall stability.
[0045] The parts not described in the present application can be realized by using or referring to the existing technology.
[0046] The above is only a specific implementation manner of the present application, but the protection scope of the present application is not limited thereto, any skilled person in the art can easily think of various changes or replacements within the technical range disclosed by the present application, which should be covered in the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.
Claims
1. A flexspline of the curvature transition type comprising a barrel having a ring gear and a flange at the bottom of the barrel, characterized in that, The bottom of the barrel has a semicircular transition area curved towards the inside of the barrel, the semicircular transition area is connected with a horizontal extension section, the horizontal extension section is connected with a vertical section, the vertical section is connected with the flange, the semicircular transition area and the horizontal extension section absorb and disperse deformation energy, thereby reducing the stress directly transmitted to the vertical section and reducing the stress concentration phenomenon at the connection between the barrel and the flange.
2. The curvature transition flexspline of claim 1 wherein, The semicircular transition area and the horizontal extension section have a first fillet transition area.
3. The curvature transition flexspline of claim 1 wherein, The horizontal extension section and the vertical section have a second fillet transition area.
4. The curvature transition flexspline of claim 1 wherein, The vertical section and the flange have a third fillet transition area.
5. The curvature transition flexspline of claim 1 wherein, The semicircular transition area and the flange have a gap, which avoids direct contact between the flexible gear and the flange during deformation.
6. The curvature transition flexspline of claim 1 wherein, The radius r of the semicircular transition area satisfies 5mm≤r≤10mm.
7. The curvature transition flexspline of claim 1 wherein, The gear ring includes a plurality of uniformly spaced tooth bodies, and the top surface of the tooth body is a plane.
8. The curvature transition flexspline of claim 7, wherein, The tooth body is provided with a first inclined surface near the upper end of the barrel and a second inclined surface at the other end, and the slope of the second inclined surface is smaller than that of the first inclined surface.
9. The curvature transition flexspline of claim 8, wherein, The tooth body includes a matching tooth part and an extension tooth part, which are connected by the second inclined surface.
10. The curvature transition flexspline of claim 9, wherein, The tooth width of the extension tooth part connected to the second inclined surface gradually increases from one end to the other end.