Cam, wave generator and harmonic reducer

Abstract

The invention provides a cam, a wave generator and a harmonic reducer. The cam comprises a cam body, and hole areas which are symmetrically distributed are arranged on the two sides of the center of the cam body in the long axis direction of the cam body; a plurality of through holes are formed in each hole area of the cam body, and the through holes are through in the axial direction of the cam body; after the cam is matched with the flexible bearing, a buffer space capable of providing elastic deformation and absorbing vibration is formed in the through hole. According to the arrangement, the cam with the through hole is designed and constructed in the position, so that not only is the self weight reduced, but also the structural strength and the structural mechanical property of the cam body can be ensured due to the fact that local materials on a long shaft with a longer size are lost; a buffer space for providing elastic deformation and absorbing vibration can be formed in the through hole with a certain span in the radial direction, and the problem of how to optimize the structure of the harmonic reducer in the prior art so as to improve the performance in the aspects of light weight, 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 cam, a wave generator and a harmonic reducer. Background Art

[0002] A harmonic reducer is a gear transmission structure that relies on a wave generator equipped with a flexible bearing to make the flexible wheel produce controllable elastic deformation and mesh with the rigid wheel to transmit motion and power. The wave generator consists of a cam and a flexible bearing, and the outer contour of the cam is usually elliptical.

[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 the existing technology in terms of light weight, 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 light weight, high speed, low noise and low vibration. Summary of the invention

[0005] In view of this, the present application provides a cam, a wave generator and a harmonic reducer to solve the problem in the prior art of how to optimize the structure of the harmonic reducer to improve the 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: A cam, applied to a harmonic reducer, comprises a cam body, wherein in the long axis direction of the cam body, two sides of the center of the cam body are provided with symmetrically distributed hole areas; The cam body is provided with a plurality of through holes in each of the hole areas, and the through holes penetrate the cam body along the axial direction; After the cam is matched with the flexible bearing, a buffer space capable of providing elastic deformation and absorbing vibration is formed in the through hole.

[0007] Optionally, the through hole includes a main hole, and the cam body is provided with the main hole in each of the hole areas, the main hole is located on the long axis of the cam body, and the distance between the main hole and the outer edge of the cam body is smaller than the distance between the main hole and the inner edge of the cam body.

[0008] Optionally, the through hole further includes auxiliary holes, and the cam body is provided with the auxiliary holes in each of the hole areas, and in each of the hole areas, the auxiliary holes are provided in an even number, and with the long axis of the cam body as the symmetry line, two of the auxiliary holes form a group and are symmetrically distributed on both sides of the main hole; The distance between each of the auxiliary holes and the outer edge of the cam body is smaller than the distance between the auxiliary hole and the inner edge of the cam body.

[0009] Optionally, in each of the hole areas, a center line connecting the main hole and all the auxiliary holes is an arc line, and the arc line is concave toward the center of the cam body.

[0010] Optionally, the through hole includes an auxiliary hole, and the cam body is provided with the auxiliary hole in each hole area, and in each hole area, the auxiliary holes are provided in an even number, and the long axis of the cam body is taken as the symmetry line, and two auxiliary holes form a group and are symmetrically distributed on both sides of the symmetry line; The distance between each of the auxiliary holes and the outer edge of the cam body is smaller than the distance between the auxiliary hole and the inner edge of the cam body.

[0011] Optionally, the main hole is a circular hole with a radius of r1, in the long axis direction of the cam body, the distance between the edge of the main hole and the outer edge of the cam body is d1, the distribution span of the main holes in the two hole areas is D1, the center distance between the main holes in the two hole areas is d, and the long axis outer diameter of the cam body is D, wherein: D = D1 + 2 × d1, D1 = d + 2 × r1; D and D1 are positively correlated, and D1 and d1 are negatively correlated; There is a positive correlation between D1 and d, and a negative correlation between d and r1.

[0012] Optionally, in the long axis direction of the cam body, the distance between the edge of the main hole and the outer edge of the cam body is d1, and the long axis outer diameter of the cam body is D, wherein: d1=a×D, 0.03226≤a≤0.08058.

[0013] Optional, a takes the value of 0.04831.

[0014] Optionally, the main hole is a circular hole with a radius of r1, and the outer diameter of the major axis of the cam body is D, wherein: 2×r1=b×D, 0.06453≤b≤0.09678.

[0015] Optionally, b takes the value 0.081.

[0016] Optionally, the main hole is a circular hole with a radius of r1, and the center distance between the main holes in the two hole areas is d; The auxiliary holes are circular holes with a radius of r2. A group of auxiliary holes is provided in each hole area. The centers of all the auxiliary holes in the two hole areas are located on a pitch circle. The pitch circle has the center of the cam body as the center. The radius of the pitch circle is R1, wherein: 2×R1=c×d, 1.063≤c≤1.078; r2=k×r1, 0.6≤k≤0.9.

[0017] Optionally, c is 1.067 and k is 0.8.

[0018] Optionally, each hole area is provided with a group of auxiliary holes, the centers of all the auxiliary holes in the two hole areas are located on a pitch circle, the pitch circle takes the center of the cam body as the center, and the angle between the line between the center of the auxiliary hole and the center of the pitch circle and the major axis of the cam body is α, wherein: 8°≤α≤12°.

[0019] Optionally, in each of the hole areas, the minimum distance between the main hole and each of the secondary holes is greater than or equal to 0.25 mm.

[0020] Optionally, the orifice of the main hole and the orifice of the secondary hole are both provided with chamfers, and the size of the chamfers is C, 0.1mm≤C≤0.5mm.

[0021] A wave generator comprises a flexible bearing and any one of the above cams, wherein the flexible bearing is sleeved on the cam.

[0022] A harmonic reducer comprises a rigid wheel, a flexible wheel and the above-mentioned wave generator.

[0023] The cam provided in the present application is applied to a harmonic reducer, and includes a cam body. In the long axis direction of the cam body, symmetrically distributed hole areas are provided on both sides of the center of the cam body; the cam body is provided with a plurality of through holes in each hole area, and the through holes penetrate the cam body along the axial direction; after the cam is matched with the flexible bearing, a buffer space that can provide elastic deformation and absorb vibration is formed in the through hole. With such arrangement, the interior of the cam body has a local material missing design at a position on the long axis, and a through hole is formed; after many tests and verifications, the applicant found that the cam designed and constructed with a through hole at the above position not only reduces its own counterweight, but also can ensure the structural strength and structural mechanical properties of the cam body due to the local material missing on the long axis with a longer size; at the same time, during the operation of the harmonic reducer, a buffer space that provides elastic deformation and absorbs vibration can be formed in the through hole with a certain span in the radial direction, 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 cams in the prior art, the cam provided by the present application can meet the performance requirements in terms 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

[0024] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying any creative work.

[0025] Figure 1 A schematic diagram of the cam structure provided in an embodiment of the present application.

[0026] Figure 2 This is a front view of the cam provided in an embodiment of the present application.

[0027] Figure 3 A schematic cross-sectional view of a cam broken along the major axis provided in an embodiment of the present application.

[0028] Figure 4 A front view of a cam with dimension markings provided in an embodiment of the present application.

[0029] exist Figure 1-Figure 4 middle: 1. Cam body; 101. Main hole; 102. Secondary hole. DETAILED DESCRIPTION

[0030] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0031] The applicant has found that the cam, as a power component of the harmonic reducer, has a very important influence on the performance of the harmonic reducer in terms of its structural design and size parameters.

[0032] like Figure 1-Figure 4 As shown, the embodiment of the present application provides a cam, which is applied to a harmonic reducer, and includes a cam body 1. In the end face of the cam body 1, in the direction of the long axis of the cam body 1, symmetrically distributed hole areas are provided on both sides of the center of the cam body 1, or it can be said that the long axis of the cam body 1 passes through the two symmetrically distributed hole areas; the cam body 1 is provided with a plurality of through holes in each hole area, and the through holes are through along the axial direction of the cam body 1; after the cam is matched with the flexible bearing, a buffer space that can provide elastic deformation and absorb vibration is formed in the through hole. As is known, the center of the cam body 1 is at the intersection of its long axis and short axis.

[0033] With such arrangement, the interior of the cam body 1 has a local material missing design at a position on the long axis, and a through hole is formed; after many tests and verifications, the applicant found that designing and constructing a cam with a through hole at the above position not only reduces its own counterweight, but also ensures the structural strength and structural mechanical properties of the cam body 1 due to the local material missing on the long axis with a longer size; at the same time, during the operation of the harmonic reducer, a buffer space that provides elastic deformation and absorbs vibration can be formed in the through hole with a certain span in the radial direction, 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 cams in the prior art, the cam provided by the present application can meet the performance requirements in terms 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.

[0034] In some preferred embodiments, the distance between each through hole and the outer edge of the cam body 1 is smaller than the distance between the through hole and the inner edge of the cam body 1, that is, the through hole is located between the inner edge and the outer edge of the cam body 1 and close to the outer edge. With this arrangement, after the cam is matched with the flexible bearing, the through hole has better performance in providing elastic deformation and absorbing vibration.

[0035] This application abandons the inherent design ideas for cams in this field. In the long-term product development and improvement practice, various cam structure designs are studied to explore the impact on the performance of the harmonic reducer. It is found that a through hole is opened inside the cam body 1 on the long axis and close to the outer edge. This is a completely different material reduction design scheme from the past. Through the breakthrough design in details, after the cam is assembled to the harmonic reducer, the performance of the harmonic reducer in many of the above aspects is improved. Outstanding technical effects have been achieved through a completely different design idea.

[0036] Moreover, the cam provided in this application has been tested and verified to have good performance in the application of small harmonic reducers, which is helpful for the design direction of miniaturization of harmonic reducers.

[0037] Regarding the number and position distribution design of the through holes, the applicant provides a variety of optional solutions.

[0038] In some optional embodiments, the through hole includes a main hole 101, and the cam body 1 is provided with a main hole 101 in each hole area. The main hole 101 is located on the long axis of the cam body 1 and passes through the cam body 1 along the axial direction; the distance between the main hole 101 and the outer edge of the cam body 1 is smaller than the distance between the main hole 101 and the inner edge of the cam body 1. After the cam is matched with the flexible bearing, a buffer space that can provide elastic deformation and absorb vibration is formed in the main hole 101.

[0039] It should be noted that, viewed from the end surface of the cam body 1 , on the basis of ensuring that the main hole 101 falls on the long axis of the cam body 1 , it is preferred that the center of the main hole 101 is located on the long axis of the cam body 1 .

[0040] In some other optional embodiments, the through hole includes an auxiliary hole 102, and the cam body 1 is provided with an auxiliary hole 102 in each hole area. In each hole area, an even number of auxiliary holes 102 are provided, and the long axis of the cam body 1 is used as the symmetry line. Two auxiliary holes 102 form a group and are symmetrically distributed on both sides of the symmetry line; the distance between each auxiliary hole 102 and the outer edge of the cam body 1 is smaller than the distance between the auxiliary hole 102 and the inner edge of the cam body 1.

[0041] In some other optional embodiments, based on the scheme that the main hole 101 is provided in the hole area, the through hole is designed to further include a secondary hole 102, and the cam body 1 is provided with a secondary hole 102 that penetrates along the axial direction of the cam body 1 in each hole area; in each hole area, there are an even number of secondary holes 102, with the long axis of the cam body 1 as the symmetry line, two secondary holes 102 form a group and are symmetrically distributed on both sides of the main hole 101, that is, an array hole group is formed in each hole area; the distance between each secondary hole 102 and the outer edge of the cam body 1 is smaller than the distance between the secondary hole 102 and the inner edge of the cam body 1, and after the cam is matched with the flexible bearing, a buffer space that can provide elastic deformation and absorb vibration is formed in the secondary hole 102. It can be optionally set so that the cross-sectional area of ​​the secondary hole 102 is smaller than the cross-sectional area of ​​the main hole 101.

[0042] With such arrangement, inside the cam body 1, there is a design of partial material missing on the long axis and near the outer edge. In addition to the main hole 101, the hole area also has a secondary hole 102. The secondary hole 102 with a certain span in the radial direction can also play a similar role to the main hole 101, that is, forming a buffer space that provides elastic deformation and absorbs vibration. In this way, the design and distribution of the secondary hole 102 can further enhance the performance of the cam in terms of lightweight, high speed, low noise and low vibration.

[0043] It should be noted that the shapes, sizes and position parameters of the main hole 101 and the auxiliary hole 102 are determined according to different working conditions of the cam. The shapes of the main hole 101 and the auxiliary hole 102 can be, but are not limited to, round holes, elliptical holes, waist-shaped holes, etc.

[0044] In addition, regarding the number of auxiliary holes 102, in a single hole area, the auxiliary holes 102 can be arranged in one group, two groups, three groups, etc.; Figure 1-Figure 4 The case where a group of auxiliary holes 102 are provided in a single hole area is exemplarily shown.

[0045] Regarding the distribution position relationship between the main hole 101 and the auxiliary holes 102, in each hole area, it can be set that the line connecting the center of the main hole 101 and the centers of all the auxiliary holes 102 forms a straight line, or it can be set that the line connecting the center of the main hole 101 and the centers of all the auxiliary holes 102 forms an arc line, and the arc line is bent toward the center of the cam body 1 or toward the outer edge of the cam body 1.

[0046] In some preferred embodiments, in each hole area, the center line connecting the main hole 101 and all the auxiliary holes 102 is an arc line, and the arc line is concave toward the center of the cam body 1, that is, the auxiliary hole 102 is closer to the outer edge of the cam body 1 than the main hole 101. In this way, the array hole group in each hole area is arranged in a concave form. After testing and verification, in the above-mentioned array hole group form in which the main hole 101 and the auxiliary hole 102 are arranged, the cam in which the auxiliary hole 102 is closer to the outer edge of the cam body 1 than the main hole 101 has better performance in optimizing the performance of the harmonic reducer.

[0047] The design parameter values ​​of the cam body 1 are not arbitrary, but need to follow a certain design basis, so as to ensure the structural strength while achieving the desired technical effect of optimizing the performance of the harmonic reducer.

[0048] In some specific embodiments, the main hole 101 is a circular hole with a radius of r1, in the long axis direction of the cam body 1, the distance between the edge of the main hole 101 and the outer edge of the cam body 1 is d1, the distribution span of the main holes 101 in the two hole areas is D1, the center distance between the main holes 101 in the two hole areas is d, and the long axis outer diameter of the cam body 1 is D, wherein: D=D1+2×d1, D1=d+2×r1; D and D1 are positively correlated, that is, the larger D is, the larger the design value of D1 is; D1 and d1 are negatively correlated, that is, the larger D1 is, the smaller the design value of d1 is; D1 and d are positively correlated, that is, the larger D1 is, the larger the design value of d is; d and r1 are negatively correlated, the larger d is, the smaller the design value of r1 is.

[0049] With such a configuration, the span D1 of the two main holes 101 on the long axis can be determined first through the basic parameter of the long axis outer diameter D of the cam body 1, and then the distance d1 between the edge of the main hole 101 and the outer edge of the cam body 1, the distance d between the centers of the two main holes 101, and the radius of the main hole 101 can be designed, thereby completing the relevant parameter design of the main hole 101. Following such a design idea is conducive to reasonably and quickly completing the overall parameter design of the cam. In this way, the radial spacing between the two main holes 101 is adaptively designed to follow the long axis size of the cam body 1, ensuring the volume of the physical part of the cam body 1, which is conducive to ensuring the structural strength of the cam body 1 as the design basis.

[0050] In some other specific embodiments, in the long axis direction of the cam body 1, the distance between the edge of the main hole 101 and the outer edge of the cam body 1 is d1, and the long axis outer diameter of the cam body 1 is D, wherein: d1=a×D, 0.03226≤a≤0.08058.

[0051] With such a setting, after testing and verification, the cam designed according to the above-mentioned ratio range can ensure that after the cam is assembled in the harmonic reducer, the uniformity of load distribution of the harmonic reducer during operation is improved.

[0052] For example, the value of a is 0.04831. Among the values ​​that can be explored, this setting can achieve the best effect.

[0053] In some other specific embodiments, the main hole 101 is a circular hole with a radius of r1, and the outer diameter of the major axis of the cam body 1 is D, wherein: 2×r1=b×D, 0.06453≤b≤0.09678.

[0054] With such a setting, after testing and verification, the cam designed according to the above-mentioned ratio range can ensure that after the cam is assembled in the harmonic reducer, the uniformity of load distribution of the harmonic reducer during operation is improved.

[0055] For example, the value of b is 0.081. Among the values ​​that can be explored, this setting can achieve the best effect.

[0056] In some other specific embodiments, the main hole 101 is a circular hole with a radius of r1, and the center distance between the main holes 101 in the two hole areas is d; the auxiliary holes 102 are circular holes with a radius of r2, and each hole area is provided with a group of auxiliary holes 102, and the centers of all the auxiliary holes 102 in the two hole areas are located on the pitch circle, the pitch circle takes the center of the cam body 1 as the center, and the radius of the pitch circle is R1, wherein: 2×R1=c×d, 1.063≤c≤1.078; r2=k×r1, 0.6≤k≤0.9.

[0057] In this way, the diameter of the pitch circle is slightly larger than the distance between the centers of the two main holes 101, that is, the auxiliary hole 102 is closer to the outer edge of the cam body 1 than the main hole 101; and at the same time, since the auxiliary hole 102 is closer to the outer edge of the cam body than the main hole 101, the size of the auxiliary hole 102 is designed to be smaller than the main hole 101, which is conducive to taking into account the structural strength of the cam body 1. After testing and verification, the cam designed according to the above ratio range can ensure that after the cam is assembled in the harmonic reducer, the load distribution uniformity of the harmonic reducer during operation is improved.

[0058] For example, c is 1.067 and k is 0.8. Among the values ​​that can be explored, this setting can achieve the best effect.

[0059] In some other specific embodiments, each hole area is provided with a group of secondary holes 102, the centers of all the secondary holes 102 in the two hole areas are located on the pitch circle, the pitch circle takes the center of the cam body 1 as the center, and the angle between the line between the center of the secondary hole 102 and the center of the pitch circle and the long axis of the cam body 1 is α, where: 8°≤α≤12°.

[0060] In this way, in each hole area, the auxiliary hole 102 is designed to be close to the main hole 101 in the circumferential direction, ensuring that each hole in the hole area is more concentratedly distributed on and near the long axis, that is, the main hole 101 and the auxiliary hole 102 are distributed as concentratedly as possible, so that the material missing parts of the cam body 1 are concentrated in the long axis direction with a larger radial dimension, thereby ensuring the structural strength of the cam body 1. After testing and verification, the cam designed according to the above range can ensure that after the cam is assembled in the harmonic reducer, the load distribution uniformity of the harmonic reducer during operation is improved.

[0061] For example, the value of α is 10°. Among the values ​​that can be explored, such a setting can achieve the best effect.

[0062] In some other specific embodiments, in each hole area, the minimum distance between the main hole 101 and each auxiliary hole 102 is greater than or equal to 0.25 mm. For example, if the main hole 101 and the auxiliary hole 102 are circular holes, the minimum distance is the distance between the centers of the circles minus the sum of the radii. With such a setting, after testing and verification, the cam designed according to the above range can ensure that after the cam is assembled in the harmonic reducer, the uniformity of the load distribution of the harmonic reducer during operation is improved.

[0063] In some other specific embodiments, the openings of the main hole 101 and the auxiliary hole 102 are both provided with chamfers, and the size of the chamfers is C, 0.1mm≤C≤0.5mm. For example, C is 0.2mm. Chamfering can remove burrs caused by machining at the openings, beautify the appearance, and reduce safety hazards by removing sharp corners; at the same time, chamfering can reduce stress concentration at the main hole 101 and the auxiliary hole 102.

[0064] It should be noted that since the main hole 101 and the auxiliary hole 102 play a key role in providing elastic deformation and absorbing vibration buffer space, and the main hole 101, the auxiliary hole 102 and the positional relationship between the two have multiple possibilities, the adjustment of many detailed parameters around the main hole 101 and the auxiliary hole 102 can bring different degrees of optimized performance. The applicant has obtained the above-mentioned parameter design ranges through a large number of comparative tests, so that a cam with better performance can be obtained within the explorable range.

[0065] Based on the above cam, the embodiment of the present application further provides a wave generator, which includes a flexible bearing and the above cam, and the flexible bearing is sleeved on the cam. Since the wave generator has the above cam, the beneficial effects of the wave generator brought by the cam can be seen in the above content, which will not be repeated here.

[0066] Based on the above-mentioned wave generator, the embodiment of the present application further provides a harmonic reducer, which includes a rigid wheel, a flexible wheel and the above-mentioned wave generator, wherein the wave generator is sleeved inside the flexible wheel, the flexible wheel is sleeved inside the rigid wheel, and the flexible wheel and the rigid wheel are meshed with teeth. Since the harmonic reducer has the above-mentioned wave generator, the beneficial effects of the harmonic reducer brought by the wave generator can be found in the above content, which will not be repeated here.

[0067] The basic principles of the present application are described above in conjunction with specific embodiments. However, it should be noted that the advantages, strengths, effects, etc. mentioned in the present application are only examples and not limitations, and it cannot be considered that these advantages, strengths, effects, etc. are required by each embodiment of the present application. In addition, the specific details disclosed above are only for the purpose of illustration and ease of understanding, not for limitation, and the above details do not limit the present application to being implemented by adopting the above specific details.

[0068] 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 diagram. As will be appreciated by those skilled in the art, these devices, apparatuses, equipment, and systems can be connected, arranged, and configured in any manner. Words such as "including", "comprising", "having", etc. are open words, referring to "including but not limited to", and can be used interchangeably with them. The words "or" and "and" used here refer to the words "and / or" and can be used interchangeably with them, unless the context clearly indicates otherwise. The words "such as" used here refer to the phrase "such as but not limited to", and can be used interchangeably with them.

[0069] It should also be noted that in the apparatus, device and method of the present application, each component or each step can be decomposed and / or recombined. Such decomposition and / or recombination should be regarded as equivalent solutions of the present application.

[0070] The above description of the disclosed aspects is provided to enable any person skilled in the art to make or use the present application. Various modifications to these aspects will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other aspects without departing from the scope of the present application. Therefore, the present application is not intended to be limited to the aspects shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

[0071] It should be understood that the qualifiers "first", "second", "third", "fourth", "fifth" and "sixth" used in the description of the embodiments of the present application are only used to more clearly explain the technical solutions and cannot be used to limit the scope of protection of the present application.

[0072] The above description has been given for the purpose of illustration and description. In addition, this description is not intended to limit the embodiments of the present 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 cam, characterized in that: The invention is applied to a harmonic reducer, comprising a cam body (1), wherein in the long axis direction of the cam body (1), two sides of the center of the cam body (1) are provided with symmetrically distributed hole areas; The cam body (1) is provided with a plurality of through holes in each of the hole areas, and the through holes penetrate the cam body (1) along the axial direction; After the cam is matched with the flexible bearing, a buffer space capable of providing elastic deformation and absorbing vibration is formed in the through hole.

2. The cam according to claim 1, characterized in that: The through hole comprises a main hole (101), the cam body (1) is provided with the main hole (101) in each hole area, the main hole (101) is located on the long axis of the cam body (1), and the distance between the main hole (101) and the outer edge of the cam body (1) is smaller than the distance between the main hole (101) and the inner edge of the cam body (1).

3. The cam according to claim 2, characterized in that: The through hole further comprises an auxiliary hole (102), and the cam body (1) is provided with the auxiliary hole (102) in each hole area. In each hole area, an even number of the auxiliary holes (102) are provided, and with the long axis of the cam body (1) as the symmetry line, two auxiliary holes (102) form a group and are symmetrically distributed on both sides of the main hole (101); The distance between each of the auxiliary holes (102) and the outer edge of the cam body (1) is smaller than the distance between the auxiliary hole (102) and the inner edge of the cam body (1).

4. The cam according to claim 3, characterized in that: In each of the hole areas, a center line connecting the main hole (101) and all the auxiliary holes (102) is an arc line, and the arc line is concave toward the center of the cam body (1).

5. The cam according to claim 1, characterized in that: The through hole comprises an auxiliary hole (102), the cam body (1) is provided with the auxiliary hole (102) in each hole area, and in each hole area, an even number of the auxiliary holes (102) are provided, and the long axis of the cam body (1) is taken as a symmetry line, and two of the auxiliary holes (102) form a group and are symmetrically distributed on both sides of the symmetry line; The distance between each of the auxiliary holes (102) and the outer edge of the cam body (1) is smaller than the distance between the auxiliary hole (102) and the inner edge of the cam body (1).

6. The cam according to any one of claims 2 to 4, characterized in that: The main hole (101) is a circular hole with a radius of r1. In the direction of the long axis of the cam body (1), the distance between the edge of the main hole (101) and the outer edge of the cam body (1) is d1. The distribution span of the main holes (101) in the two hole areas is D1. The center distance between the main holes (101) in the two hole areas is d. The long axis outer diameter of the cam body (1) is D, wherein: D = D1 + 2 × d1, D1 = d + 2 × r1; D and D1 are positively correlated, and D1 and d1 are negatively correlated; There is a positive correlation between D1 and d, and a negative correlation between d and r1.

7. The cam according to any one of claims 2 to 4, characterized in that: In the long axis direction of the cam body (1), the distance between the edge of the main hole (101) and the outer edge of the cam body (1) is d1, and the long axis outer diameter of the cam body (1) is D, wherein: d1=a×D, 0.03226≤a≤0.08058.

8. The cam according to claim 7, characterized in that: The value of a is 0.04831.

9. The cam according to any one of claims 2 to 4, characterized in that: The main hole (101) is a circular hole with a radius of r1, and the outer diameter of the major axis of the cam body (1) is D, wherein: 2×r1=b×D, 0.06453≤b≤0.09678.

10. The cam according to claim 9, characterized in that: The value of b is 0.

081.

11. The cam according to claim 3, characterized in that: The main hole (101) is a circular hole with a radius of r1, and the center distance between the main holes (101) in the two hole areas is d; The auxiliary holes (102) are circular holes with a radius of r2. Each hole area is provided with a group of auxiliary holes (102). The centers of all the auxiliary holes (102) in the two hole areas are located on a pitch circle. The pitch circle has the center of the cam body (1) as the center. The radius of the pitch circle is R1, wherein: 2×R1=c×d, 1.063≤c≤1.078; r2=k×r1, 0.6≤k≤0.

9.

12. The cam according to claim 11, characterized in that The value of c is 1.067 and the value of k is 0.

8.

13. The cam according to claim 3 or 11, characterized in that: A group of auxiliary holes (102) is provided in each hole area, the centers of all the auxiliary holes (102) in the two hole areas are located on a pitch circle, the pitch circle has the center of the cam body (1) as the center, and the angle between the line between the center of the auxiliary hole (102) and the center of the pitch circle and the major axis of the cam body (1) is α, wherein: 8°≤α≤12°。 14. The cam according to any one of claims 2 to 4, characterized in that: In each of the hole areas, the minimum distance between the main hole (101) and each of the secondary holes (102) is greater than or equal to 0.25 mm.

15. The cam according to any one of claims 2 to 4, characterized in that: The opening of the main hole (101) and the opening of the auxiliary hole (102) are both provided with chamfers, and the size of the chamfers is C, 0.1 mm≤C≤0.5 mm.

16. A wave generator, characterized in that: It comprises a flexible bearing and a cam as described in any one of claims 1 to 15, wherein the flexible bearing is sleeved on the cam.

17. A harmonic reducer, characterized in that: It comprises a rigid wheel, a flexible wheel and the wave generator as claimed in claim 16.

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