High-strength flexible gear for harmonic reducer

Abstract

The high-strength flexible gear comprises a cylinder and a cylinder bottom flange, the cylinder comprises a gear ring section and a cylinder section, a fillet transition section is arranged between the cylinder section and the cylinder bottom flange, and a plurality of reinforcing ribs evenly distributed around the circle center of the cylinder section are arranged on the inner wall of the cylinder section. The reinforcing ribs extend to the position, corresponding to the tail end of the gear ring, of the inner wall of the barrel body from the fillet transition section so as to enhance the overall strength of the flexible gear, the rigidity of the inner wall of the barrel section of the flexible gear is remarkably improved through introduction of the reinforcing ribs, and the reinforcing ribs are arranged on the inner wall of the barrel section and extend to the position, corresponding to the tail end of the gear ring, of the inner wall of the barrel body from the fillet transition section. The reinforcing ribs are evenly distributed around the circle center of the cylinder section and extend to the position, corresponding to the tail end of the gear ring, of the inner wall of the cylinder body from the fillet transition section, a stable supporting network is formed, and assembly prestress generated when the wave generator is installed in a flexible gear is dispersed and reduced. Therefore, the risk of local plastic deformation or breakage of the flexible gear due to uneven stress is reduced.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of flexspline for harmonic reducer, and particularly relates to a high-strength flexspline for harmonic reducer. BACKGROUND

[0002] A harmonic reducer is a kind of precision mechanical transmission device, and its core structure contains three key components: flexspline, rigid gear and wave generator. The flexspline is a kind of thin-walled elastic element designed with an outer gear ring, and its internal structure is adapted to the outer ring of a flexible bearing. In contrast, the rigid gear is a solid annular component with an inner gear ring, and the number of its teeth is usually two more than that of the flexspline. In the working mechanism, the flexspline is elastically deformed under the action of external force, and then presents an elliptical shape. In this deformation process, the teeth at the long axis position of the flexspline will accurately embed into the tooth groove of the rigid gear, forming a close meshing state; while the teeth at the short axis position are completely out of contact, in a non-meshing state. With the continuous rotation of the wave generator, the flexspline constantly experiences such elastic deformation, and its teeth are cyclically converted between the states of meshing in, meshing out and disengaging, producing the relative movement between the teeth. This process effectively realizes the power transmission between the wave generator and the flexspline.

[0003] The harmonic reducer has been widely used in key parts such as robot joints due to its multiple advantages such as compact structure, small size, high transmission precision, large transmission ratio range, strong carrying capacity and superior transmission efficiency. However, the flexspline of the harmonic reducer causes a series of complex problems due to periodic elastic deformation, and the fatigue fracture of the flexspline is particularly prominent, which accounts for more than 60% of the total failure proportion, and becomes a key factor restricting the service life of the harmonic reducer. The smooth cylinder wall part of the flexspline is the most vulnerable area, especially the transition area of the smooth cylinder wall and the gear ring or tooth, which is prone to stress concentration. Long-term stress concentration will cause material fatigue and then lead to fracture, therefore, preventing the damage of this part is crucial to improve the overall performance and reliability of the harmonic reducer. Therefore, the prior art needs to be further improved and improved. CONTENT OF THE UTILITY MODEL

[0004] The utility model provides a kind of high-strength flexspline for harmonic reducer to solve the problem that flexspline smooth cylinder wall part structure interface single, in smooth cylinder wall and gear ring transition area stress concentration intensity deficiency and be damaged, or at least provide a kind of beneficial alternative.

[0005] To achieve the above object, the utility model provides the following technical scheme:

[0006] A high-strength flexible wheel for a harmonic reducer includes a cylinder and a bottom flange. The cylinder includes a gear ring section and a cylindrical section. A rounded transition section is provided between the cylindrical section and the bottom flange. Multiple reinforcing ribs are provided on the inner wall of the cylindrical section, evenly arranged around the center of the cylindrical section. The reinforcing ribs extend from the rounded transition section to the inner wall of the cylinder corresponding to the end of the gear ring, so as to enhance the overall strength of the flexible wheel.

[0007] The aforementioned structure significantly increases the stiffness of the inner wall of the flexure cylindrical section by introducing reinforcing ribs. The reinforcing ribs are arranged on the inner wall of the cylindrical section and extend from the rounded transition section to the inner wall of the cylinder corresponding to the end of the gear ring, so that they do not come into contact with or interfere with the wave generator. The reinforcing ribs are evenly distributed around the center of the cylindrical section and extend from the rounded transition section to the inner wall of the cylinder corresponding to the end of the gear ring, forming a stable support network. This helps to disperse and reduce the assembly prestress generated when the wave generator is installed into the flexure, thereby reducing the risk of local plastic deformation or fracture of the flexure due to uneven stress.

[0008] In a preferred implementation, the number of reinforcing ribs corresponds to the number of teeth on the gear ring.

[0009] The number of reinforcing ribs corresponds to the number of teeth on the gear ring, thus forming a dense support network around the gear ring, which significantly improves the overall stiffness of the flexible wheel, enabling it to better resist external loads and deformation.

[0010] In a preferred implementation, the reinforcing rib is vertically aligned with the teeth of the gear ring or vertically aligned with the grooves between adjacent teeth of the gear ring.

[0011] When the reinforcing ribs align vertically with the teeth of the gear ring, they provide additional support near the teeth. This helps reduce local deformation caused by stress on the gear ring teeth, thereby enhancing the strength of the flexure in that area. When the reinforcing ribs align vertically with the tooth grooves between adjacent gear ring teeth, they provide support in the tooth groove area, thereby reducing stress concentration caused by the shape of the tooth grooves. This helps reduce the risk of fatigue failure of the flexure in that area.

[0012] In a preferred implementation, the radial cross-section of the reinforcing rib is arc-shaped.

[0013] In a preferred embodiment, the reinforcing rib has a deformation gap between the end of the bottom flange of the cylinder and the rounded transition section.

[0014] When the flexure is subjected to the action of the wave generator, especially during the inward stretching process in the area corresponding to the short axis of the wave generator, the reinforcing rib comes into contact with the rounded transition section. As a structural support, the reinforcing rib effectively transmits the force generated by the wave generator to the rounded transition section, and then distributes it throughout the entire flexure structure. The contact between the reinforcing rib and the rounded transition section limits the degree of deformation of the flexure in certain directions. This limiting effect not only helps maintain the geometry of the flexure but also ensures stable transmission performance throughout its entire working cycle, extending its service life.

[0015] In a preferred embodiment, the gear ring is composed of multiple evenly spaced teeth, each tooth having a mating tooth portion and an extending tooth portion. The height of the extending tooth portion is lower than the height of the mating tooth portion and extends to the cylindrical section. The tooth groove extends from the top of the cylinder to the end of the extending tooth portion, and the end of the reinforcing rib corresponds to the position on the inner wall of the cylinder corresponding to the end of the extending tooth portion.

[0016] The mating teeth are the part of the gear ring that directly meshes with the rigid gear. The extended teeth are lower in height than the mating teeth and extend into the cylindrical section, which helps to enhance the rigidity and stability of the gear ring, while reducing the risk of fatigue failure caused by stress concentration.

[0017] In a preferred implementation, the mating teeth and the extended teeth are connected by a first inclined plane with a gradually decreasing slope.

[0018] In a preferred embodiment, a second inclined surface is provided on the side of the toothed part near the upper part of the cylinder, and the slope of the second inclined surface is greater than that of the first inclined surface.

[0019] In the preferred implementation, the top surface of the mating teeth is a plane.

[0020] In the preferred implementation, the teeth are higher in the middle and lower on both sides. Attached Figure Description

[0021] 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:

[0022] Figure 1 A three-dimensional schematic diagram illustrating one embodiment of the high-strength flexible wheel of this application is shown;

[0023] Figure 2 It is illustrated Figure 1 An enlarged schematic diagram of one possible implementation of Part A;

[0024] Figure 3 A top view schematic diagram illustrating one embodiment of the high-strength flexible wheel of this application is shown;

[0025] Figure 4A schematic cross-sectional view of a schematic embodiment of the application is shown in Figure 3 A schematic cross-sectional view of a schematic embodiment of the application is shown in

[0026] Figure 5 A schematic cross-sectional view of a schematic embodiment of the application is shown in Figure 4 A schematic cross-sectional view of a schematic embodiment of the application is shown in

[0027] BRIEF DESCRIPTION OF THE DRAWINGS

[0028] 1. barrel; 10, gear ring segment; 100, tooth; 101, tooth slot; 1001, mating tooth portion; 10010, first inclined surface; 1002, extension tooth portion; 1003, second inclined surface; 11, cylindrical segment; 110, reinforcing rib; 1101, deformation gap; 12, rounded transition segment; 2, barrel bottom flange. DETAILED DESCRIPTION

[0029] Hereinafter, only certain exemplary embodiments are simply described. As can be appreciated by those skilled in the art, the described embodiments can be modified in various different manners without departing from the spirit and scope of the present application. Therefore, the drawings and the description are considered to be essentially exemplary rather than limiting.

[0030] In the description of the present application, it needs to be understood that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "axial", "radial", "circumferential" and the like is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the device or element 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 present application. In the present application, unless otherwise explicitly specified and limited, the first feature "on" or "under" the second feature can be that the first and second features are in direct contact, or the first and second features are indirectly in contact through an intermediate medium.

[0031] In the present application, unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connecting", "fixing" and the like should be understood broadly, for example, it can be fixed connection, or detachable connection, or integral; 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 noted that direct connection means that the connection between the two main bodies does not form a connection relationship through an excessive structure, but is connected to form a whole only through the connecting structure. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0032] 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.

[0033] The present invention will now be described with reference to the accompanying drawings.

[0034] The specific solution adopted is as follows:

[0035] like Figures 1-5 As shown, this utility model provides a high-strength flexible wheel for a harmonic reducer, including a cylinder body 1 and a bottom flange. The cylinder body 1 includes a gear ring section 10 and a cylindrical section 11. A rounded transition section 12 is provided between the cylindrical section 11 and the bottom flange 2. Multiple reinforcing ribs 110 are provided on the inner wall of the cylindrical section 11, which are evenly arranged around the center of the cylindrical section 11. The reinforcing ribs 110 extend from the rounded transition section 12 to the inner wall position of the cylinder body 1 corresponding to the end of the gear ring 100, so as to enhance the overall strength of the flexible wheel.

[0036] By employing the high-strength flexible wheel for the harmonic reducer of this application, the introduction of the reinforcing rib 110 significantly increases the stiffness of the inner wall of the cylindrical section 11 of the flexible wheel. The reinforcing rib 110 is arranged on the inner wall of the cylindrical section 11 and extends from the rounded transition section 12 to the inner wall position of the cylinder 1 corresponding to the end of the 100 teeth, so that it will not contact and interfere with the wave generator. The reinforcing rib 110 is evenly distributed around the center of the cylindrical section 11 and extends from the rounded transition section 12 to the inner wall position of the cylinder 1 corresponding to the end of the 100 teeth, forming a stable support network. This helps to disperse and reduce the assembly prestress generated when the wave generator is installed into the flexible wheel, thereby reducing the risk of local plastic deformation or fracture of the flexible wheel due to uneven stress.

[0037] When the wave generator is fitted with the flexure, the flexure is forced into an elliptical shape. The presence of the reinforcing rib 110 guides the stress distribution, resulting in more uniform deformation of the flexure in the corresponding regions of the long and short axes. In the region corresponding to the long axis of the wave generator, when the flexure is elongated, the reinforcing rib 110 provides additional support, reducing strain caused by tension. In the region corresponding to the short axis, the reinforcing rib 110 helps resist inward tensile forces, preventing excessive thinning and cracking of the material. Due to the strengthening effect of the reinforcing rib 110, the flexure can better maintain its shape stability and material integrity during cyclic deformation. This helps reduce material fatigue caused by long-term stress concentration, thereby significantly improving the fatigue life and overall reliability of the flexure.

[0038] The flexible wheel design with reinforced ribs 110 is more adaptable to various complex working conditions and extreme load conditions. Whether in heavy-load, high-speed, or frequent start-stop applications, it can exhibit more stable and reliable performance.

[0039] As a preferred embodiment of the present application, the number of reinforcing ribs 110 corresponds to the number of tooth 100 circles.

[0040] The number of reinforcing ribs 110 corresponds to the number of tooth 100 circles, thereby forming a dense support network around the tooth 100 circles, significantly improving the overall stiffness of the flexspline, enabling it to better resist external loads and deformations, and the matching of reinforcing ribs 110 with the number of tooth 100 circles of the tooth 100, the stress distribution on the flexspline is more uniform, reducing the risk of local plastic deformation or fracture due to stress concentration.

[0041] As a preferred embodiment of the present application, the reinforcing ribs 110 vertically correspond to the tooth 100 circles of the tooth 100 or correspond to the tooth space 101 between adjacent tooth 100 circles of the tooth 100.

[0042] When the reinforcing ribs 110 vertically correspond to the tooth 100 circles of the tooth 100, they can provide additional support near the tooth 100 circles of the tooth 100. This helps to reduce local deformation caused by the stress on the tooth 100 circles of the tooth 100, thereby enhancing the strength of the flexspline in this area and enabling more effective stress dispersion in the transition area near the tooth 100 circles of the tooth 100. During the operation of the harmonic reducer, the tooth 100 circles of the tooth 100 are the main load-bearing components. The vertical correspondence of the reinforcing ribs 110 helps to distribute these stresses more evenly throughout the flexspline structure, thereby reducing the risk of stress concentration.

[0043] When the reinforcing ribs 110 vertically correspond to the tooth space 101 between adjacent tooth 100 circles of the tooth 100, they can provide support in the tooth space 101 area, thereby reducing stress concentration phenomena caused by the shape of the tooth space 101. This helps to reduce the risk of fatigue failure of the flexspline in this area.

[0044] The layout of reinforcing ribs 110 vertically corresponding to the tooth space 101 also helps to optimize the dynamic performance of the harmonic reducer. By reducing stress concentration and improving overall stability, this layout can reduce the negative impact of the flexspline on vibration and noise, thereby improving the smooth operation of the harmonic reducer.

[0045] As a preferred embodiment of the present application, the radial cross-section of the reinforcing ribs 110 is in the shape of a circular arc.

[0046] The reinforcing ribs 110 with a circular arc-shaped cross-section can more effectively disperse stress when subjected to external forces, and compared to reinforcing ribs 110 with straight or rectangular cross-sections, the circular arc-shaped cross-section can better adapt to the periodic elastic deformation of the flexspline under the action of the wave generator, thereby optimizing stress distribution and reducing the risk of fatigue failure.

[0047] As a preferred embodiment of the present application, see Figure 5 The reinforcing rib 110 has a deformation gap 1101 between the flange end of the cylinder bottom and the fillet transition section 12.

[0048] When the flexspline is subjected to the action of the wave generator, especially in the process of being inwardly stretched in the area corresponding to the minor axis of the wave generator, the reinforcing rib 110 comes into contact with the fillet transition section 12. The reinforcing rib 110, as a structural support, can effectively transmit the force generated by the wave generator to the fillet transition section 12, and then to the entire flexspline structure. The abutment of the reinforcing rib 110 and the fillet transition section 12 limits the degree of deformation of the flexspline in certain directions. This limiting effect not only helps to maintain the geometric shape of the flexspline, but also ensures that it can maintain stable transmission performance throughout the working cycle, prolonging the service life of the flexspline.

[0049] Referring to Figure 2 The tooth 100 ring is composed of a plurality of uniformly spaced teeth 100. The tooth 100 has a mating tooth portion 1001 and an extension tooth portion 1002. The extension tooth portion 1002 extends to the cylindrical section 11 with a height lower than that of the mating tooth portion 1001. The tooth groove 101 extends from the top end of the cylinder body 1 to the end of the extension tooth portion 1002. The end of the reinforcing rib 110 corresponds to the position of the inner wall of the cylinder body 1 corresponding to the end of the extension tooth portion 1002. Further, the mating tooth portion 1001 and the extension tooth portion 1002 are connected by a first slope 10010 with gradually decreasing slope.

[0050] The mating tooth portion 1001 is the part of the tooth 100 ring that directly engages with the rigid gear tooth 100 wheel. Its height is designed to meet the engagement requirements. The extension tooth portion 1002 has a height lower than that of the mating tooth portion 1001 and extends to the cylindrical section 11, which helps to enhance the rigidity and stability of the tooth 100 ring and reduce the risk of fatigue failure caused by stress concentration. The mating tooth portion 1001 and the extension tooth portion 1002 are connected by a first slope 10010 with gradually decreasing slope, which helps to reduce stress concentration caused by sudden changes in tooth 100 shape and improve the fatigue resistance of the tooth 100 ring.

[0051] The tooth groove 101 extends from the top end of the cylinder body 1 to the end of the extension tooth portion 1002, maintaining the integrity and stability of the tooth 100 ring. In addition, the tooth groove 101 can also play a role in heat dissipation, helping to reduce the temperature of the harmonic reducer during operation. The end of the reinforcing rib 110 corresponds to the position of the inner wall of the cylinder body 1 corresponding to the end of the extension tooth portion 1002, which helps to enhance the overall structural strength of the flexspline. The reinforcing rib 110, as a structural support, can prevent excessive deformation or damage of the flexspline during transmission. At the same time, the reinforcing rib 110 can also optimize the stress distribution inside the flexspline, reducing the risk of fatigue failure caused by stress concentration.

[0052] As a preferred embodiment of the present application, the second slope 1003 is arranged on one side of the upper part of the barrel 1, and the slope of the second slope 1003 is greater than that of the first slope 10010. The design of the second slope 1003 helps to disperse the stress of the engaging tooth part 1001 during meshing. Because of the larger slope, the stress can be more evenly distributed to the entire structure of the tooth 100 ring, reducing the risk of fatigue failure caused by stress concentration. The second slope 1003 with a larger slope can enhance the rigidity of the tooth 100 ring. During meshing, the tooth 100 ring can better resist deformation and maintain stable transmission performance.

[0053] Referring to Figure 2 The top surface of the engaging tooth part 1001 is a plane, and further, the engaging tooth part 1001 is high in the middle and low on both sides.

[0054] The top surface of the engaging tooth part 1001 is designed as a plane, which helps to ensure the precision during meshing with the gear tooth 100 wheel. The plane top surface can provide a stable contact surface, reducing vibration and noise caused by uneven tooth 100 surface. The design of the engaging tooth part 1001 being high in the middle and low on both sides actually forms a "reinforced rib" effect on the tooth 100 part. It can enhance the structural strength of the tooth 100 part, so that it can better resist deformation and damage.

[0055] The parts not described in the present application can be realized by using or referring to the existing technology.

[0056] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited to this. Any skilled person in the art can easily think of various changes or replacements within the technical scope disclosed by the present application, which should be covered within 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 high-strength flexspline for a harmonic reducer, comprising a cylinder and a cylinder bottom flange, the cylinder comprising a ring gear section and a cylindrical section, characterized in that, A fillet transition section is arranged between the cylindrical section and the flange of the cylinder bottom, and a plurality of reinforcing ribs are arranged uniformly around the center of the cylindrical section on the inner wall of the cylindrical section, the reinforcing ribs extending from the fillet transition section to the position of the inner wall of the cylinder corresponding to the end of the gear ring, so as to enhance the overall strength of the flexible gear.

2. The high-strength flexspline for a harmonic reducer according to claim 1, characterized by, The number of the reinforcing ribs corresponds to the number of the gear ring teeth.

3. The high-strength flexspline for a harmonic reducer according to claim 1, characterized by, The reinforcing ribs correspond to the vertical direction of the gear ring teeth or the vertical direction of the tooth groove between adjacent gear ring teeth.

4. The high-strength flexspline for a harmonic reducer according to claim 1, characterized by, The radial section of the reinforcing rib is in the shape of a circular arc.

5. The high-strength flexspline for a harmonic reducer according to claim 1, characterized by, The reinforcing rib has a deformation gap between the end close to the flange of the cylinder bottom and the fillet transition section.

6. The high-strength flexspline for a harmonic reducer according to claim 1, characterized by, The gear ring is composed of a plurality of uniformly spaced teeth, the teeth have a matching tooth portion and an extended tooth portion, the height of the extended tooth portion is lower than that of the matching tooth portion and extends to the cylindrical section, the tooth groove extends from the top end of the cylinder to the end of the extended tooth portion, and the end of the reinforcing rib corresponds to the position of the inner wall of the cylinder corresponding to the end of the extended tooth portion.

7. The high-strength flexspline for a harmonic reducer according to claim 6, characterized by The matching tooth portion and the extended tooth portion are connected by a first inclined surface with gradually decreasing slope.

8. The high-strength flexspline for a harmonic reducer according to claim 7, characterized by The matching tooth portion is provided with a second inclined surface on one side close to the upper part of the cylinder, and the slope of the second inclined surface is greater than that of the first inclined surface.

9. The high-strength flexspline for a harmonic reducer according to claim 6, characterized by, The top surface of the matching tooth portion is a plane.

10. The high-strength flexspline for a harmonic reducer according to claim 9, characterized by The matching tooth portion is higher in the middle and lower on both sides.

Images