Circular spline and harmonic reducer

Abstract

The present application provides a rigid gear and a harmonic reducer. The rigid gear includes a rigid gear body and rigid gear teeth. The inner ring surface of the rigid gear body includes a tooth region, and a plurality of rigid gear teeth are distributed in the tooth region, and each rigid gear tooth extends along the axial direction of the rigid gear body; a material removal region is provided on the tooth top surface of the rigid gear tooth, and the material removal region includes a wavy surface segment. In a cross-section where the axis of the rigid gear body is located, the wavy surface segment is in a wavy line shape extending along the axial direction of the rigid gear body; after the rigid gear meshes with the flexible gear, a buffer space capable of providing elastic deformation and absorbing vibration is formed in the material removal region. In this way, the rigid gear with a wavy surface segment designed and constructed in the material removal region reduces its own weight, reduces the contact area with the flexible gear, a buffer space capable of providing elastic deformation and absorbing vibration is formed in the material removal region, the load distribution during the operation of the harmonic reducer is more uniform, and the problem of how to optimize the structure of the harmonic reducer in the prior art to improve its performance in terms of lightweight, high speed, low noise, and small vibration is solved.

Description

Technical Field

[0001] The present application relates to the technical field of harmonic reducers, and in particular to a rigid wheel and a harmonic reducer. Background Art

[0002] The harmonic reducer is mainly composed of a rigid wheel, a flexwheel and a wave generator. The harmonic reducer is a gear transmission structure that relies on the wave generator to make the flexwheel produce controllable elastic deformation and meshes with the rigid wheel to transmit motion and power. The wave generator consists of a cam and a flexible bearing.

[0003] In recent years, with the rapid development of the robotics industry, especially the updating and iteration of collaborative robots and humanoid robots, the requirements for harmonic reducers used in robots have gradually increased. However, the performance of harmonic reducers in existing technologies in terms of lightweight, high speed, low noise and low vibration is difficult to meet the design requirements of robots.

[0004] Therefore, it is particularly important to optimize the structure of the harmonic reducer to improve its performance in terms of lightweight, high speed, low noise and low vibration. Summary of the Invention

[0005] In view of this, the present application provides a rigid wheel and a harmonic reducer to solve the problem in the prior art of how to optimize the structure of the harmonic reducer to improve its performance in terms of light weight, high speed, low noise and low vibration.

[0006] In order to achieve the above objectives, this application provides the following technical solutions:

[0007] A rigid wheel, applied to a harmonic reducer, comprising:

[0008] A rigid wheel body, wherein the inner annular surface of the rigid wheel body includes a tooth area;

[0009] There are multiple steel wheel teeth distributed in the tooth area, each of the steel wheel teeth extends along the axial direction of the steel wheel body, and the steel wheel teeth have a material reduction area on the tooth top surface, and the material reduction area includes a wave surface segment. In the cross section where the axis of the steel wheel body is located, the wave surface segment is in the shape of a wave line extending along the axial direction of the steel wheel body;

[0010] Wherein, after the rigid wheel and the flexible wheel are engaged, a buffer space capable of providing elastic deformation and absorbing vibration is formed in the material reduction area.

[0011] Optionally, the material reduction zone further includes a first inclined surface segment and a second inclined surface segment, and in the axial direction of the rigid wheel body, the first inclined surface segment and the second inclined surface segment are respectively located on both sides of the wave surface segment;

[0012] In the cross-section where the axis of the rigid gear body is located, both the first inclined surface segment and the second inclined surface segment are in the shape of an oblique line, and both are inclined in the direction approaching the axis of the rigid gear body from the side connected to the wavy surface segment to the other side.

[0013] Optionally, the inner ring surface of the rigid gear body further includes a non-tooth region, the non-tooth region and the tooth region are distributed along the axial direction of the rigid gear body, the first inclined surface segment is located on the side of the wavy surface segment away from the non-tooth region, and the second inclined surface segment is located on the side of the wavy surface segment close to the non-tooth region, where:

[0014] The projection dimension of the first inclined surface segment in the axial direction of the rigid gear body is h1, the projection dimension of the second inclined surface segment in the axial direction of the rigid gear body is h2, and h1≥h2; and / or,

[0015] The angle between the extended plane where the first inclined surface segment is located and the axis of the rigid gear body is α, the angle between the extended plane where the second inclined surface segment is located and the axis of the rigid gear body is β, and α≥β.

[0016] Optionally, in the cross-section where the axis of the rigid gear body is located, the length of the rigid gear tooth in the axial direction of the rigid gear body is H, the projection dimension of the wavy surface segment in the axial direction of the rigid gear body is h, the radii of the multiple arc surface segments forming the wavy surface segment are all R, the projection dimension of the first inclined surface segment in the axial direction of the rigid gear body is h1, and the projection dimension of the second inclined surface segment in the axial direction of the rigid gear body is h2, where:

[0017] h and R are in a positive correlation;

[0018] H = h + h1 + h2, and h and h1 + h2 are in a negative correlation.

[0019] Optionally, the wavy surface segment includes a first concave arc surface segment, a first convex arc surface segment, a second concave arc surface segment, a second convex arc surface segment, and a third concave arc surface segment that are sequentially distributed along the axial direction of the rigid gear body.

[0020] Optionally, in the cross-section where the axis of the rigid gear body is located, the length of the rigid gear tooth in the axial direction of the rigid gear body is H, the projection dimension of the first inclined surface segment in the axial direction of the rigid gear body is h1, the projection dimension of the second inclined surface segment in the axial direction of the rigid gear body is h2, and the radii of the first concave arc surface segment, the first convex arc surface segment, the second concave arc surface segment, the second convex arc surface segment, and the third concave arc surface segment are all R, where:

[0021] H = h1 + h2 + a×5×R, and 0.24≤a≤0.31.

[0022] Optionally, the value of a is 0.26687.

[0023] Optionally, the radii of the multiple arc segments forming the wavy surface segment are all R, the inner diameter of the rigid gear body at the most convex point of the wavy surface segment is d, and the inner diameter at the most concave point of the wavy surface segment is D, where:

[0024] R and D are negatively correlated, and R and d are positively correlated.

[0025] Optionally, the inner diameter of the rigid gear body at the most convex point of the wavy surface segment is d, and the inner diameter at the most concave point of the wavy surface segment is D. The depth of the most concave point of the wavy surface segment relative to the most convex point is d1, where:

[0026] D = d + 2×d1.

[0027] Optionally, the angle between the extended plane where the first inclined surface segment is located and the axis of the rigid gear body is α, and the angle between the extended plane where the second inclined surface segment is located and the axis of the rigid gear body is β, 1°≤α≤5°, 1°≤β≤5°.

[0028] Optionally, at both ends of the rigid gear teeth, one end is connected to the rigid gear body by a curved surface transition or an inclined surface transition, and the other end is connected to the rigid gear body by a curved surface transition or an inclined surface transition.

[0029] A harmonic reducer includes a crossed roller bearing, a wave generator, a flexible gear, and a rigid gear in any one of the above. The wave generator is sleeved inside the flexible gear, the flexible gear is sleeved inside the rigid gear, and the flexible gear teeth of the flexible gear mesh with the rigid gear teeth. The outer ring of the crossed roller bearing is connected to the rigid gear.

[0030] The spline provided in the present application is applied to a harmonic reducer, and includes a spline body and spline teeth. The inner annular surface of the spline body includes a tooth area, in which a plurality of spline teeth are distributed, and each spline tooth extends along the axial direction of the spline body. The spline teeth have a tooth top surface provided with a material reduction area, and the material reduction area includes a wavy surface segment. In the cross section where the axis of the spline body is located, the wavy surface segment is in the shape of a wavy line extending along the axial direction of the spline body. After the spline is meshed with the flexspline, a buffer space that can provide elastic deformation and absorb vibration is formed in the material reduction area. With such a configuration, the inner annular surface of the rigid wheel body is the surface of the rigid wheel used to cooperate with the flexible wheel, and the rigid wheel teeth mesh with the flexible wheel teeth for transmission. There is a design with local material missing on the tooth top surface of the rigid wheel teeth, forming a reduced material area. After many tests and verifications, the applicant found that designing and constructing a rigid wheel with a wave surface segment in the reduced material area not only reduces its own counterweight and reduces the contact area with the flexible wheel, so that the rigid wheel has better structural mechanical properties, but also forms a buffer space in the reduced material area during the operation of the harmonic reducer to provide elastic deformation and absorb vibration, so that the load distribution of the harmonic reducer during operation is more uniform, which is conducive to the high-speed, low-noise and low-vibration operation of the harmonic reducer. Compared with the conventional rigid wheel in the prior art, the rigid wheel provided by the present application can meet the performance requirements of lightweight, high-speed, low-noise and low-vibration, and solves the problem of how to optimize the structure of the harmonic reducer in the prior art to improve the performance in terms of lightweight, high-speed, low-noise and low-vibration. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are merely embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without any creative work.

[0032] Figure 1 A schematic structural diagram of the rigid wheel provided in an embodiment of the present application.

[0033] Figure 2 This is a front view of the rigid wheel provided in an embodiment of the present application.

[0034] Figure 3 A schematic cross-sectional view of a rigid wheel provided in an embodiment of the present application.

[0035] Figure 4 for Figure 3 Partial schematic diagram at point A in the middle.

[0036] Figure 5 for Figure 3 The dimension marking diagram at A in the middle.

[0037] Figure 6Schematic assembly diagram of the harmonic reducer provided by the embodiment of the present application.

[0038] Figure 7 Schematic cross-sectional view of the harmonic reducer provided by the embodiment of the present application.

[0039] In Figures 1-7 :

[0040] 1. Rigid gear; 2. Flexspline; 3. Flexible bearing; 4. Cam; 5. Crossed roller bearing

[0041] 11. Rigid gear body; 12. Rigid gear teeth; 13. Non-tooth area

[0042] 121. Material removal area

[0043] 1211. Wavy surface section; 1212. First inclined surface section; 1213. Second inclined surface section Detailed implementation manners

[0044] The following will clearly and completely describe the technical solutions in the embodiments of the present application with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present application without creative efforts shall fall within the protection scope of the present application.

[0045] The applicant found that as one of the core components of the harmonic reducer, the structural design and dimensional parameters of the rigid gear 1 play a quite important role in the performance of the harmonic reducer.

[0046] As Figures 1-5 shown, the embodiment of the present application provides a rigid gear 1, which is applied to a harmonic reducer. The rigid gear 1 includes a rigid gear body 11 and rigid gear teeth 12. The inner ring surface of the rigid gear body 11 includes a tooth area, and a plurality of rigid gear teeth 12 are distributed in the tooth area. Each rigid gear tooth 12 extends along the axial direction of the rigid gear body 11; a material removal area 121 is provided on the tooth top surface of the rigid gear tooth 12. The material removal area 121 includes a wavy surface section 1211. The wavy surface section 1211 includes a plurality of connected arc surfaces and forms an uneven shape. In the cross-section where the axis of the rigid gear body 11 is located, that is, the axial section, the wavy surface section 1211 is in the shape of a wavy line extending along the axial direction of the rigid gear body 11; after the rigid gear 1 meshes with the flexspline 2, a buffer space capable of providing elastic deformation and absorbing vibration is formed in the material removal area 121.

[0047] As is well known in the art, the inner ring surface of the rigid gear 1 is the surface for meshing and assembling with the flexspline 2; the shape of the rigid gear tooth 12 is usually such that it has two tooth side surfaces and a tooth top surface located between the two tooth side surfaces, and there is an included angle between the two tooth side surfaces.

[0048] With such a setting, the inner ring surface of the rigid gear body 11 is the surface of the rigid gear 1 for mating with the flexible gear 2. The rigid gear teeth 12 mesh with the flexible gear teeth for transmission. There is a design with local material missing on the tooth top surface of the rigid gear teeth 12, forming a material removal area 121. Through multiple tests and verifications by the applicant, it is found that for the rigid gear 1 with a wavy surface section 1211 designed and constructed in the material removal area 121, not only does it reduce its own weight, decrease the contact area with the flexible gear 2, making the rigid gear 1 have better structural mechanical properties, but also during the operation of the harmonic reducer, a buffer space for providing elastic deformation and absorbing vibration is formed in the material removal area 121, making the load distribution during the operation of the harmonic reducer more uniform, which is beneficial to the high-speed, low-noise, and small-vibration operation of the harmonic reducer. Compared with the conventional rigid gear 1 in the prior art, the rigid gear 1 provided in this application can meet the performance requirements in terms of lightweight, high speed, low noise, and small vibration, and solves the problem of how to optimize the structure of the harmonic reducer in the prior art to improve the performance in terms of lightweight, high speed, low noise, and small vibration.

[0049] This application abandons the inherent design concept of the rigid gear 1 in this field. During the long-term product R & D and improvement practice, the influence of various rigid gear 1 structural designs on the performance of the harmonic reducer is explored, and it is obtained that the tooth top surface of the rigid gear teeth 12 is designed to be wavy, which is a completely different structural material removal design scheme from the past. Through the breakthrough design in details, after the rigid gear 1 is assembled into the harmonic reducer, the performance of the harmonic reducer in the above-mentioned aspects is improved, and outstanding technical effects are achieved through a completely different design concept.

[0050] Moreover, the rigid gear 1 provided in this application has good performance in the application of small harmonic reducers through tests and verifications, which is helpful for the design direction of miniaturization of harmonic reducers.

[0051] In some alternative embodiments, a local area on the tooth top surface of the rigid gear teeth 12 is the material removal area 121, or the entire area of the tooth top surface of the rigid gear teeth 12 is the material removal area 121. It is preferably designed that the entire area of the tooth top surface is the material removal area 121.

[0052] In some alternative embodiments, the material removal area 121 further includes a first inclined surface section 1212 and a second inclined surface section 1213. Axially of the rigid gear body 11, the first inclined surface section 1212 and the second inclined surface section 1213 are respectively located on both sides of the wavy surface section 1211; in the cross-section where the axis of the rigid gear body 11 is located, both the first inclined surface section 1212 and the second inclined surface section 1213 are in the shape of an inclined line, and both are inclined from the side connected to the wavy surface section 1211 to the other side towards the direction close to the axis of the rigid gear body 11. That is, the first inclined surface section 1212 and the second inclined surface section 1213 form a material removal design different from the shape of the wavy surface section 1211.

[0053] With such a setting, on the basis that the wave surface section 1211 is designed in the material removal area 121, a design with inclined surface sections on both sides is further formed. Through experiments and verification, it can further reduce the self-weight of the rigid gear 1, reduce the contact area between the rigid gear 1 and the flexible gear 2, and reduce the adverse stress and shear effects of the rigid gear teeth 12, thereby further optimizing the structural mechanical properties of the rigid gear 1, further enhancing the role of the rigid gear 1 in providing elastic deformation and absorbing vibration, and thus further enhancing the performance of the rigid gear 1 in terms of contributing to the lightweight, high-speed, low-noise, and small-vibration of the harmonic reducer.

[0054] In some other alternative embodiments, the inner ring surface of the rigid gear body 11 further includes a non-tooth area 13. The non-tooth area 13 and the tooth area are distributed along the axial direction of the rigid gear body 11. The first inclined surface section 1212 is located on the side of the wave surface section 1211 away from the non-tooth area 13, and the second inclined surface section 1213 is located on the side of the wave surface section 1211 close to the non-tooth area 13, where: the projection dimension of the first inclined surface section 1212 in the axial direction of the rigid gear body 11 is h1, the projection dimension of the second inclined surface section 1213 in the axial direction of the rigid gear body 11 is h2, and h1≥h2; and / or, the angle between the extended plane where the first inclined surface section 1212 is located and the axis of the rigid gear body 11 is α, the angle between the extended plane where the second inclined surface section 1213 is located and the axis of the rigid gear body 11 is β, and α≥β.

[0055] With such a setting, the first inclined surface section 1212 and the second inclined surface section 1213 can be designed as a symmetric structure, that is, h1 = h2 and α = β; in addition, considering that the loading sizes and working conditions on the inner and outer sides of the rigid gear 1 are generally different, the first inclined surface section 1212 and the second inclined surface section 1213 can also be designed as an asymmetric structure. Since the first inclined surface section 1212 is located at a position close to the end face of the rigid gear 1 and the second inclined surface section 1213 is located at the middle position of the rigid gear 1, it is preferably set that the axial dimension of the first inclined surface section 1212 is longer than that of the second inclined surface section 1213, and the inclination angle of the first inclined surface section 1212 is also larger than that of the second inclined surface section 1213, that is, h1>h2, α>β, which is beneficial to the rigid gear 1 having better structural mechanical properties.

[0056] It should be noted that in this application, the design parameter values of the rigid gear 1 are not arbitrary and need to follow a certain design basis and be controlled in terms of shape design and parameter design. Only in this way can the structural strength of the rigid gear 1 be ensured while enabling the rigid gear 1 to have the function of providing elastic deformation and absorbing vibration, so as to achieve the technical effect of optimizing the performance of the harmonic reducer as required.

[0057] In some other alternative embodiments, in the cross-section where the axis of the rigid gear body 11 is located, the length of the rigid gear teeth 12 in the axial direction of the rigid gear body 11 is H, the projection dimension of the wavy surface segment 1211 in the axial direction of the rigid gear body 11 is h, the radii of the multiple arc surface segments that make up the wavy surface segment 1211 are all R, the projection dimension of the first inclined surface segment 1212 in the axial direction of the rigid gear body 11 is h1, and the projection dimension of the second inclined surface segment 1213 in the axial direction of the rigid gear body 11 is h2, where: h and R are positively correlated, that is, the larger R is, the larger the design value of h is; H = h + h1 + h2, and h and h1 + h2 are negatively correlated, that is, the larger R is, the larger h is, and the smaller the design value of h1 + h2 is.

[0058] With such a setting, on the one hand, the projection dimension of the wavy surface segment 1211 in the axial direction is the chord length corresponding to the arc surface segment, and there is a known calculation formula between the chord length, R, and the central angle corresponding to the arc surface segment, that is, the size of the chord length is affected by R and the central angle. When designing the specific parameters of the wavy surface segment 1211, it should be ensured that the central angle corresponding to the arc surface segment is a certain value or within a small design range, preferably an obtuse angle. Following such a design, the larger the selected value of R is, the larger the design value of h is, and the undulation degree and distribution range of the wavy surface segment 1211 are adapted. With such a design of the material-removing area 121, the rigid gear 1 can provide elastic deformation and absorb vibration, and the effect of making the load distribution uniformity during the operation of the harmonic reducer can reach a better level; on the other hand, the axial length H of the rigid gear teeth 12 should be within a certain design range. Therefore, when h is larger, the design value of h1 + h2 is smaller, ensuring that the axial length of the rigid gear teeth 12 is adapted to the axial length of the flexspline teeth.

[0059] More specifically, the number of arc surface segments that make up the wavy surface segment 1211 can take values among 2, 3, 4, 5, and 6.

[0060] In some specific embodiments, the number of arc surface segments that make up the wavy surface segment 1211 is selected as 5, and the wavy surface segment 1211 includes a first concave arc surface segment, a first convex arc surface segment, a second concave arc surface segment, a second convex arc surface segment, and a third concave arc surface segment that are sequentially distributed along the axial direction of the rigid gear body 11. In this way, through experiments and verification, when the wavy surface segment 1211 on the tooth top surface has five arc surface segments, it is easy to design the values of R, h, h1, and h2, and after the rigid gear 1 participates in the assembly of the harmonic reducer, the harmonic reducer can obtain a better load distribution uniformity effect during operation.

[0061] In some specific embodiments, in the cross-section where the axis of the rigid gear body 11 is located, the length of the rigid gear teeth 12 in the axial direction of the rigid gear body 11 is H, the projected dimension of the first inclined surface segment 1212 in the axial direction of the rigid gear body 11 is h1, the projected dimension of the second inclined surface segment 1213 in the axial direction of the rigid gear body 11 is h2, and the radii of the first concave arc segment, the first convex arc segment, the second concave arc segment, the second convex arc segment, and the third concave arc segment are all R, where:

[0062] H = h1 + h2 + a×5×R, 0.24 ≤ a ≤ 0.31.

[0063] With such a setting, through the optimal design of the parameters of various different rigid gear teeth 12 and the material removal area 121, the above relationship is obtained through simulation, and it has better coordination in terms of taking into account the structural strength of the rigid gear 1, providing elastic deformation and absorbing vibration, and optimizing the load distribution uniformity effect.

[0064] More preferably, the value of a is 0.26687.

[0065] In some other specific embodiments, the radii of the multiple arc segments constituting the wavy surface segment 1211 are all R, the inner diameter of the rigid gear body 11 at the most convex point of the wavy surface segment 1211 is d, and the inner diameter of the rigid gear body 11 at the most concave point of the wavy surface segment 1211 is D, where: R and D are negatively correlated, and R and d are positively correlated. That is, the larger R is, the smaller D is, and the larger d is.

[0066] With such a setting, designed according to the above-mentioned value-taking method, it conforms to the rule that the larger R is, the smaller the undulation degree of the wavy surface segment 1211 is. Following such a design, in tests and verifications, after the rigid gear 1 participates in the assembly of the harmonic reducer, the harmonic reducer obtains a better load distribution uniformity effect during operation.

[0067] In some other specific embodiments, the inner diameter of the rigid gear body 11 at the most convex point of the wavy surface segment 1211 is d, and the inner diameter of the rigid gear body 11 at the most concave point of the wavy surface segment 1211 is D, and the depth of the most concave point of the wavy surface segment 1211 relative to the most convex point is d1, where: D = d + 2×d1.

[0068] With such a setting, the lowest points of the wavy surface segments 1211 of each rigid gear tooth 12 are all on the same circle, and the highest points of the wavy surface segments 1211 at each place are all on the same circle. That is, the wavy surface segments 1211 of each rigid gear tooth 12 have high consistency, which is beneficial to ensuring the improvement of the load distribution uniformity of the harmonic reducer during operation after the rigid gear 1 participates in the assembly of the harmonic reducer.

[0069] In some other specific embodiments, the angle between the extension plane of the first inclined plane segment 1212 and the axis of the rigid gear body 11 is α, and the angle between the extension plane of the second inclined plane segment 1213 and the axis of the rigid gear body 11 is β, where 1° ≤ α ≤ 5° and 1° ≤ β ≤ 5°. With such a setting, the inclination angles of the inclined plane segments on both sides of the wavy surface segment 1211 are controlled within the above angle range, and in combination with the surface profiling design of the material removal area 121, better performance of the rigid gear 1 within the exploration range can be obtained.

[0070] In some other preferred embodiments, among the two ends of the rigid gear teeth 12, one end is connected to the rigid gear body 11 through a curved surface transition or an inclined surface transition, and the other end is connected to the rigid gear body 11 through a curved surface transition or an inclined surface transition; preferably, both ends of the rigid gear teeth 12 are connected to the rigid gear body 11 through an inclined surface transition. With such a setting, chamfers are formed between the two ends of the rigid gear teeth 12 and the rigid gear body 11, which is convenient for the installation and disassembly between the rigid gear 1 and the flexible gear 2.

[0071] As Figures 6-7 shown, based on the above rigid gear 1, an embodiment of the present application further provides a harmonic reducer, which includes a crossed roller bearing 5, a wave generator, a flexible gear 2, and the above rigid gear 1. The wave generator is sleeved inside the flexible gear 2, the flexible gear 2 is sleeved inside the rigid gear 1, and the flexible gear teeth of the flexible gear 2 mesh with the rigid gear teeth 12. The wave generator includes a flexible bearing 3 and a cam 4. The flexible bearing 3 is sleeved outside the cam 4. The crossed roller bearing 5 includes an inner ring and an outer ring, and the outer ring of the crossed roller bearing 5 is connected to the rigid gear 1 through a fastener. Since the harmonic reducer has the above rigid gear 1, for the beneficial effects brought by the rigid gear 1 to the harmonic reducer, please refer to the above content and will not be elaborated here.

[0072] The basic principle of the present application has been described above in combination with specific embodiments. However, it should be noted that the advantages, advantages, effects, etc. mentioned in the present application are only examples and not limitations. It cannot be considered that these advantages, advantages, effects, etc. are essential for each embodiment of the present application. In addition, the above-disclosed specific details are only for the purpose of illustration and easy understanding, rather than limitations. The above details do not limit the present application to necessarily adopt the above specific details to implement.

[0073] The block diagrams of the devices, apparatuses, equipment, and systems involved in this application are only illustrative examples and are not intended to require or imply that they must be connected, arranged, and configured in the manner shown in the block diagrams. As those skilled in the art will recognize, these devices, apparatuses, equipment, and systems can be connected, arranged, and configured in any way. Words such as "including", "comprising", "having", etc. are open-ended terms, meaning "including but not limited to", and can be used interchangeably with each other. The words "or" and "and" used herein refer to the phrase "and / or", and can be used interchangeably with it, unless the context clearly indicates otherwise. The phrase "such as" used herein refers to the phrase "such as but not limited to", and can be used interchangeably with it.

[0074] It should also be noted that in the devices, equipment, and methods of this application, each component or each step can be decomposed and / or recombined. These decompositions and / or recombinations should be regarded as equivalent solutions of this application.

[0075] The above description of the disclosed aspects is provided to enable any person skilled in the art to make or use this application. Various modifications to these aspects will be very apparent to those skilled in the art, and the general principles defined herein can be applied to other aspects without departing from the scope of this application. Therefore, this application is not intended to be limited to the aspects shown herein, but rather to the broadest scope consistent with the principles and novel features disclosed herein.

[0076] It should be understood that the qualifiers "first", "second", "third", "fourth", "fifth", and "sixth" used in the description of the embodiments of this application are only for more clearly explaining the technical solutions and cannot be used to limit the protection scope of this application.

[0077] The above description has been given for purposes of illustration and description. In addition, this description is not intended to limit the embodiments of this application to the forms disclosed herein. Although multiple example aspects and embodiments have been discussed above, those skilled in the art will recognize certain variations, modifications, changes, additions, and sub-combinations thereof.

Claims

1. A rigid gear, characterized in that, Applied to a harmonic reducer, including: A rigid gear body (11), the inner ring surface of the rigid gear body (11) includes a tooth region; Rigid gear teeth (12), there are multiple and distributed in the tooth region, each of the rigid gear teeth (12) extends along the axial direction of the rigid gear body (11), and a material removal region (121) is provided on the tooth top surface of the rigid gear teeth (12), the material removal region (121) includes a wavy surface section (1211), a first inclined surface section (1212) and a second inclined surface section (1213), in the axial direction of the rigid gear body (11), the first inclined surface section (1212) and the second inclined surface section (1213) are respectively located on both sides of the wavy surface section (1211), in the cross-section where the axis of the rigid gear body (11) is located, the wavy surface section (1211) is in a wavy line shape extending along the axial direction of the rigid gear body (11), the first inclined surface section (1212) and the second inclined surface section (1213) are both in a slant line shape, and both are inclined from the side connected to the wavy surface section (1211) to the other side towards the direction close to the axis of the rigid gear body (11); Wherein, after the rigid gear (1) meshes with the flexible gear (2), a buffer space capable of providing elastic deformation and absorbing vibration is formed in the material removal region (121).

2. The rigid gear according to claim 1, characterized in that, The inner ring surface of the rigid gear body (11) further includes a non-tooth region (13), the non-tooth region (13) and the tooth region are distributed along the axial direction of the rigid gear body (11), the first inclined surface section (1212) is located on the side of the wavy surface section (1211) away from the non-tooth region (13), the second inclined surface section (1213) is located on the side of the wavy surface section (1211) close to the non-tooth region (13), wherein: The projection dimension of the first inclined surface section (1212) in the axial direction of the rigid gear body (11) is h1, the projection dimension of the second inclined surface section (1213) in the axial direction of the rigid gear body (11) is h2, h1≥h2; and / or, The included angle between the extended surface where the first inclined surface section (1212) is located and the axis of the rigid gear body (11) is α, the included angle between the extended surface where the second inclined surface section (1213) is located and the axis of the rigid gear body (11) is β, α≥β.

3. The rigid gear according to claim 1, wherein In the cross-section where the axis of the rigid gear body (11) is located, the length of the rigid gear teeth (12) in the axial direction of the rigid gear body (11) is H, the projection dimension of the wavy surface section (1211) in the axial direction of the rigid gear body (11) is h, the radii of the multiple arc surface sections forming the wavy surface section (1211) are all R, the projection dimension of the first inclined surface section (1212) in the axial direction of the rigid gear body (11) is h1, the projection dimension of the second inclined surface section (1213) in the axial direction of the rigid gear body (11) is h2, wherein: h and R are in a positive correlation relationship; H = h + h1 + h2, h and h1 + h2 are in a negative correlation relationship.

4. The rigid gear according to claim 1, characterized in that, The wavy surface section (1211) includes a first concave arc surface section, a first convex arc surface section, a second concave arc surface section, a second convex arc surface section, and a third concave arc surface section that are sequentially distributed along the axial direction of the rigid gear body (11).

5. The rigid gear according to claim 4, characterized in that, In the cross-section where the axis of the rigid gear body (11) is located, the length of the rigid gear teeth (12) in the axial direction of the rigid gear body (11) is H, the projected dimension of the first inclined surface section (1212) in the axial direction of the rigid gear body (11) is h1, the projected dimension of the second inclined surface section (1213) in the axial direction of the rigid gear body (11) is h2, and the radii of the first concave arc surface section, the first convex arc surface section, the second concave arc surface section, the second convex arc surface section, and the third concave arc surface section are all R, where: H = h1 + h2 + a × 5 × R, 0.24 ≤ a ≤ 0.

31.

6. The rigid gear according to claim 5, characterized in that, a takes the value of 0.26687.

7. The rigid gear according to claim 1, characterized in that, The radii of the multiple arc surface sections that make up the wavy surface section (1211) are all R. The inner diameter of the rigid gear body (11) at the most convex point of the wavy surface section (1211) is d, and the inner diameter of the rigid gear body (11) at the most concave point of the wavy surface section (1211) is D, where: R and D are negatively correlated, and R and d are positively correlated.

8. The rigid gear according to claim 1, wherein The inner diameter of the rigid gear body (11) at the most convex point of the wavy surface section (1211) is d, and the inner diameter of the rigid gear body (11) at the most concave point of the wavy surface section (1211) is D. The depth of the most concave point of the wavy surface section (1211) relative to the most convex point is d1, where: D = d + 2 × d1.

9. The rigid gear according to claim 1, wherein, The angle between the extended plane where the first inclined surface section (1212) is located and the axis of the rigid gear body (11) is α, and the angle between the extended plane where the second inclined surface section (1213) is located and the axis of the rigid gear body (11) is β, 1° ≤ α ≤ 5°, 1° ≤ β ≤ 5°.

10. The rigid gear according to claim 1, characterized in that, Among the two ends of the rigid gear teeth (12), one end is connected to the rigid gear body (11) by a curved surface transition or an inclined surface transition, and the other end is connected to the rigid gear body (11) by a curved surface transition or an inclined surface transition.

11. A harmonic reducer, characterized in that, It includes a crossed roller bearing (5), a wave generator, a flexible gear (2), and a rigid gear (1) as described in any one of claims 1-10. The wave generator is sleeved inside the flexible gear (2), the flexible gear (2) is sleeved inside the rigid gear (1), and the flexible gear teeth of the flexible gear (2) mesh with the rigid gear teeth (12). The outer ring of the crossed roller bearing (5) is connected to the rigid gear (1).

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