Wave generator, harmonic reducer and mechanical arm joint

Abstract

The invention discloses a wave generator, a harmonic reducer and a mechanical arm joint, and aims at solving the problems that in a harmonic reducer on a traditional mechanical arm joint, a wave generator is complex in structure, high in cost, poor in durability and the like. The wave generator comprises a cam, a bearing and a flexible gear bushing; the cam is provided with a cam body and a protruding part, the protruding part is provided with an installation shaft, an inner ring of the bearing is installed on the installation shaft in a matched mode, an outer ring of the bearing abuts against the flexible gear lining, the cam rotates to drive the bearing to revolve along the axis center point of the cam, and the flexible gear lining generates periodic deformation. A conventional bearing is arranged on the installation shaft of the protruding part to replace a flexible bearing, deformation of the flexible gear can be achieved, the durability of the wave generator is improved, the service life of the wave generator is prolonged, meanwhile, the conventional bearing is convenient to machine and install and stable in operation, the manufacturing and installation cost of the wave generator is reduced, and the maintenance and replacement probability is also reduced.

Description

Technical Field

[0001] The invention relates to the field of flexible-wheel harmonic reducer series, and in particular to a wave generator, a harmonic reducer and a mechanical arm joint. Background Art

[0002] Harmonic reducers have the characteristics of high transmission efficiency, small size, light weight, smooth transmission and low noise, and are widely used in the field of robotics, especially in collaborative robotic arms and service robots. With the development of robotics technology, the requirements for the size and accuracy of harmonics are becoming more and more stringent.

[0003] The traditional harmonic reducer consists of three parts: wave generator, flexible wheel and steel wheel. The camshaft, flexible bearing and flexible wheel of the wave generator are installed layer by layer from the inside to the outside. The existing wave generator pushes the flexible wheel to deform through the flexible bearing through the cam. The cam presses part of the flexible wheel to the steel wheel, while the other part of the flexible wheel is separated from the steel wheel. During the process of the cam rotating one circle, the flexible wheel will complete a complete deformation and recovery process, and the steel wheel will rotate a certain angle, thereby achieving a deceleration effect.

[0004] In the existing harmonic reducer, the wave generator needs to be provided with a flexible bearing on the outside of the cam, which makes the structure of the wave generator complex and the cost high. In addition, during long-term operation, the provision of the flexible bearing will affect the durability of the wave generator. Summary of the invention

[0005] The purpose of the present invention is to provide a wave generator, a harmonic reducer and a robotic arm joint, aiming to solve the problems of the harmonic reducer on the traditional robotic arm joint, such as the complex structure of the wave generator, high cost and poor durability.

[0006] To solve the above problems, a first aspect of the present invention provides a wave generator, the wave generator comprising: a cam, a bearing and a flexspline bushing;

[0007] The cam is formed with a cam body and at least two protrusions, each of the protrusions is provided with at least one mounting shaft, the number of the bearings corresponds one to one with the number of the mounting shafts, the inner ring of the bearing is adapted to be mounted on the mounting shaft, the outer ring of the bearing abuts against the flexible wheel bushing, the cam rotates, driving the bearing to revolve along the axial center point of the cam, the flexible wheel bushing is used to reduce the wear of the bearing, and the flexible wheel bushing produces periodic deformation.

[0008] Through such a setting, a mounting shaft is set on the protruding part of the cam, and the bearing on the mounting shaft rotates with the cam, thereby prompting the flexible wheel bushing to drive the flexible wheel to deform. In a traditional wave generator, a flexible bearing is usually sleeved on the outer periphery of the cam, and the flexible bearing is squeezed by the cam to deform, driving the flexible wheel to deform so that the flexible wheel and the steel wheel periodically mesh and produce motion displacement. The processing difficulty and cost of the flexible bearing are relatively high, and the long-term operation makes it difficult to guarantee the performance of the flexible bearing, thereby affecting the durability of the wave generator. By adopting a conventional bearing setting method on the mounting shaft of the protruding part, the function of replacing the flexible bearing can be realized, and the durability of the wave generator is improved. At the same time, the conventional bearing is easy to process, easy to install, and stable in operation, which reduces the manufacturing and installation cost of the wave generator, and also reduces the probability of maintenance and replacement. The flexible wheel bushing is set between the bearing and the flexible wheel to reduce the friction between the bearing and the flexible wheel and improve the durability of the bearing.

[0009] Preferably, the protrusions are symmetrically distributed along the center of the cam body.

[0010] Through such an arrangement, when the cam rotates, the protrusions symmetrically distributed along the center of the cam body cause the flexible wheel bushing to deform evenly and stably, so that the wave generator runs more smoothly.

[0011] Preferably, when each of the protruding portions is provided with a mounting shaft, the mounting shaft is arranged at an end portion close to the protruding portion;

[0012] When a plurality of the mounting shafts are disposed on each of the protruding portions, the plurality of the mounting shafts are evenly arranged at the ends of the protruding portions.

[0013] With such an arrangement, when an installation shaft is arranged, the installation shaft is arranged at the end of the protrusion, that is, the bearing is located at the front end of the protrusion, and when the bearing pushes the flexible wheel bushing to deform, the supporting force of the bearing on the flexible wheel bushing is along the axial direction of the protrusion. At this time, the supporting effect of the bearing on the flexible wheel bushing is better, which is beneficial to improving the stability of the wave generator; when multiple installation shafts are arranged on each protrusion, the contact between the flexible wheel bushing and the flexible wheel is more stable by increasing the supporting area of ​​the flexible wheel bushing near the protrusion, and the multiple installation shafts are evenly arranged, so that the bearings are evenly distributed on the protrusion, and the supporting force on the flexible wheel bushing is more uniform and stable, which is beneficial to improving the durability of the wave generator.

[0014] Preferably, the mounting shaft includes a first shaft and a second shaft, the first shaft is arranged on a first surface of the cam, and the second shaft is arranged on a second surface of the cam.

[0015] Through such an arrangement, mounting shafts are arranged on both sides of the cam to improve the supporting effect on the flexible wheel bushing. Compared with the arrangement of bearings on one side of the cam, the arrangement of bearings on both sides makes the contact of the flexible wheel bushing with the flexible wheel more stable and the rotation of the flexible wheel smoother.

[0016] According to another aspect of the present invention, a harmonic reducer is provided. The harmonic reducer comprises: a steel wheel assembly, a flexspline, and a wave generator. The flexspline bushing of the wave generator abuts against the flexspline.

[0017] The wave generator causes the flexible wheel and the steel wheel assembly to mesh and rotate, and the meshing tooth difference between the flexible wheel and the steel wheel assembly produces a moving variable, causing the flexible wheel bushing to deform periodically, thereby reducing the wear of the wave generator and improving the transmission effect.

[0018] According to another aspect of the present invention, there is provided a mechanical arm joint, the mechanical arm joint comprising a housing, a motor assembly, a harmonic reducer and an output flange;

[0019] The motor assembly is arranged in the housing, and the motor assembly drives the output flange to rotate through the harmonic reducer;

[0020] The harmonic reducer comprises a steel wheel assembly, a flexible wheel and a wave generator, wherein the wave generator is mounted to the inner periphery of the flexible wheel;

[0021] The outer teeth of the flexible wheel mesh with the inner teeth of the steel wheel assembly;

[0022] The wave generator includes the wave generator described above.

[0023] Through such a setting, in the harmonic reducer on the joint of the mechanical arm, the above-mentioned wave generator is used, the motor assembly drives the cam to rotate, the bearing on the cam causes the flexible wheel to deform through the flexible wheel bushing, and the outer teeth of the flexible wheel mesh with the inner teeth of the steel wheel assembly, so that the steel wheel assembly moves and drives the output flange to rotate. The wave generator runs more stably to ensure the output accuracy of the harmonic reducer; the conventional bearing setting in the wave generator replaces the flexible bearing, improves the strength and rigidity of the wave generator, ensures the stability and reliability of the harmonic reducer, and thus improves the stability and reliability of the mechanical arm joint.

[0024] Preferably, the motor assembly includes a drive plate, a motor stator and a motor rotor, the motor stator is fixedly connected to the inner side of the shell, the harmonic reducer also includes a camshaft, the camshaft is fixedly connected to the motor rotor, the drive plate drives the motor rotor to drive the camshaft to rotate, and the camshaft is fixedly connected to the cam.

[0025] Through such a setting, during the operation of the robot arm joint, the motor rotor drives the camshaft to rotate, thereby realizing the rotation of the cam. The fixedly connected motor rotor and camshaft are beneficial to improving the stability of the transmission of the motor assembly to the wave generator. At the same time, the camshaft is fixedly connected to the cam, which further makes the rotation of the cam more stable and controllable.

[0026] Preferably, the steel wheel assembly includes a first steel wheel and a second steel wheel, the first steel wheel is fixedly connected to the housing, the second steel wheel is fixedly connected to the output flange, the outer ring of the flexible wheel is connected to the inner ring of the first steel wheel via tooth meshing at the junction of the flexible wheel bushing and the inner ring of the flexible wheel, the outer ring of the flexible wheel is connected to the inner ring of the second steel wheel via tooth meshing, the number of teeth on the inner ring of the first steel wheel is different from the number of teeth on the inner ring of the second steel wheel, and the number of teeth on the outer ring of the flexible wheel is the same as the number of teeth on the inner ring of the first steel wheel or the second steel wheel.

[0027] Through such an arrangement, the flexible wheel drives the first steel wheel and the second steel wheel to rotate. The number of teeth on the inner ring of the first steel wheel is different from the number of teeth on the inner ring of the second steel wheel. When the flexible wheel drives the first steel wheel and the second steel wheel, there is a speed difference between the first steel wheel and the second steel wheel, thereby achieving a deceleration effect.

[0028] Preferably, the mechanical arm joint further comprises an output shaft arranged in the housing, the output shaft is integrally formed with the output flange or connected via a connecting piece, and the camshaft is sleeved on the output shaft.

[0029] Through such a setting, the output shaft is set in the shell to support the output flange to make its movement more stable. At the same time, the output shaft can be used for routing, which makes the overall appearance of the robot arm joint neater and also plays a role in protecting the circuit.

[0030] Preferably, the mechanical arm joint further includes an encoder disposed in the housing, and the encoder is used to collect motion information of the camshaft.

[0031] Through this setting, the encoder collects the motion information of the camshaft and combines it with the actual movement of the output flange to improve the accuracy of motion control and thus improve the stability of the robot arm joint. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 is a schematic structural diagram of a wave generator according to a first embodiment of the present invention;

[0033] Figure 2 is a top view of a cam in a wave generator according to a first embodiment of the present invention;

[0034] Figure 3 is a schematic structural diagram of a cam in a wave generator according to a first embodiment of the present invention;

[0035] Figure 4 is a schematic structural diagram of a wave generator according to a second embodiment of the present invention;

[0036] Figure 5 is a top view of a cam in a wave generator according to a second embodiment of the present invention;

[0037] Figure 6 is a schematic structural diagram of a cam in a wave generator according to a second embodiment of the present invention;

[0038] Figure 7 Schematic diagram of the joint structure of a robot arm according to the third embodiment of the present invention.

[0039] Reference numerals:

[0040] 1. Wave generator;

[0041] 11, cam; 111, cam body; 112, protrusion; 113, mounting shaft; 113a, first shaft; 113b, second shaft;

[0042] 12. Bearings;

[0043] 13. Flexspline bushing;

[0044] 1000, Robotic arm joints;

[0045] 1010, housing;

[0046] 1020, motor assembly; 1021, drive board; 1022, motor stator; 1023, motor rotor;

[0047] 1030, harmonic reducer; 1031, steel wheel assembly; 1031a, first steel wheel; 1031b, second steel wheel; 1032, camshaft;

[0048] 1040, output flange;

[0049] 1050, output shaft;

[0050] 1060. Encoder. DETAILED DESCRIPTION

[0051] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention is further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings. It should be understood that these descriptions are only exemplary and are not intended to limit the scope of the present invention. In addition, in the following description, the description of well-known structures and technologies is omitted to avoid unnecessary confusion of the concept of the present invention.

[0052] The accompanying drawings show schematic diagrams of layer structures according to embodiments of the present invention. These figures are not drawn to scale, and some details are magnified and some details may be omitted for the purpose of clarity. The shapes of various regions and layers shown in the figures and the relative sizes and positional relationships therebetween are only exemplary, and may deviate in practice due to manufacturing tolerances or technical limitations, and those skilled in the art may additionally design regions / layers with different shapes, sizes, and relative positions according to actual needs.

[0053] Combination Figure 1 and Figure 2 The first aspect of the present invention provides a wave generator 1, which includes: a cam 11, a bearing 12 and a flexible wheel bushing 13; the cam 11 is formed with a cam body 111 and a protrusion 112, the protrusion 112 is provided with a mounting shaft 113, the inner ring of the bearing 12 is adapted to be mounted on the mounting shaft 113, the outer ring of the bearing 12 is in contact with the flexible wheel bushing 13, the cam 11 rotates, driving the bearing 12 mounted on the protrusion 112 to rotate, driving the bearing 12 to revolve along the axis center point of the cam 11, the flexible wheel bushing 13 is used to reduce the wear of the bearing 12, and the moving variable generated by the meshing tooth difference between the flexible wheel and the steel wheel causes the flexible wheel bushing 13 to produce periodic deformation to reduce the wear between the bearing 12 and the flexible wheel. The cam body 111 and the protrusion 112 are formed on the cam 11, and the mounting shaft 113 on the protrusion 112 is used to mount the shaft 113 bearing, and the rotation of the cam 11 drives the bearing 12 to move and the flexible wheel bushing 13 to deform. Through such a setting, a mounting shaft 113 is provided on the protruding portion 112 of the cam 11, and the bearing 12 on the mounting shaft 113 rotates with the cam 11, thereby causing the flexible wheel bushing 13 to deform, thereby forming a regular wave generator 1. In a conventional wave generator 1, a flexible bearing is usually sleeved on the outer periphery of the cam 11, and the flexible bearing is squeezed by the cam 11 to deform, driving the flexible wheel to deform so that the flexible wheel and the steel wheel periodically mesh and generate motion displacement. The processing difficulty and cost of the flexible bearing are relatively high, and the long-term operation makes it difficult to ensure the performance of the flexible bearing, thereby affecting the durability of the wave generator 1. By using a conventional bearing 12 to be arranged on the mounting shaft 113 of the protruding portion 112 to replace the flexible bearing, the deformation of the flexible wheel bushing 13 can be achieved, and the durability of the wave generator 1 is improved. At the same time, the conventional bearing 12 is easy to process, easy to install, and stable in operation, which reduces the manufacturing and installation cost of the wave generator 1, and also reduces the probability of maintenance and replacement, thereby extending the practical life.

[0054] It should be noted that the specific shape of the protrusion 112 is not limited here, and it only needs to be able to cause the flexible wheel bushing 13 to deform during the rotation of the cam 11. The setting relationship between the cam body 111 and the protrusion 112 is not limited either. The cam body 111 and the protrusion 112 may be separately set, and the cam body 111 and the protrusion 112 may be fixedly connected; preferably, the protrusion 112 and the cam body 111 are integrally formed to improve the integrity of the structure and achieve a better transmission effect. The connection relationship between the installation shaft 113 and the cam 11 is not limited either. The installation shaft 113 and the protrusion 112 of the cam 11 may be fixedly connected, or the installation shaft 113 and the protrusion 112 may be integrally formed. In a preferred case, the installation shaft 113 and the protrusion 112 of the cam 11 are integrally formed to enhance the support strength of the cam 11 and the installation shaft 113 to the bearing 12. The specific position of the mounting shaft 113 on the cam 11 is not limited here. It should be noted that after the bearing 12 is sleeved on the mounting shaft 113, it is sufficient to ensure that the outer ring of the bearing 12 is in contact with the inner ring of the flexible wheel bushing 13. Through such a setting, the cam 11 can directly push the flexible wheel bushing 13 to deform through the bearing 12 during the rotation process. The size of the bearing 12 is not limited either. The size of the bearing 12 is selected according to the distance from the mounting shaft 113 to the inner ring of the flexible wheel bushing 13, ensuring that the bearing 12 can support the flexible wheel bushing 13 to deform after being sleeved on the mounting shaft 113. Specifically, the bearing 12 can adopt a conventional bearing 12 structure to achieve the universal use of the bearing 12 on the cam 11, avoiding the need to specially process and produce a specific type of flexible bearing in the traditional wave generator 1. Through such a setting, the cost can be well controlled. At the same time, the durability of the conventional bearing 12 is much higher than that of the flexible bearing, thereby significantly improving the service life of the wave generator 1, avoiding frequent maintenance and replacement work, and improving work efficiency.

[0055] The number of stages of the cam 11 is not limited here. In a preferred case, the number of stages of the cam 11 of the cam 11 is greater than or equal to two, and the plurality of protrusions 112 are symmetrically distributed along the center of the circle of the cam body 111. Through such an arrangement, two or more cam 11 stages are provided with two or more protrusions 112 correspondingly. When the cam 11 rotates, the evenly arranged protrusions 112 cause the flexible wheel bushing 13 to deform evenly and stably, so that the wave generator 1 runs more smoothly. The multi-stage design of the cam 11 improves the smoothness and accuracy of the movement, and the protrusions 112 evenly arranged along the circumference enhance the continuity and stability of the movement.

[0056] It should be noted that the number of mounting shafts 113 provided on each protrusion 112 is not limited here, and one or more mounting shafts 113 may be provided on each protrusion 112. Figures 1 to 3In one embodiment of the present invention, there is provided a cam 11 with two stages, and each protrusion 112 is provided with a mounting shaft 113, and the mounting shaft 113 is arranged at the end of the protrusion 112, that is, the bearing 12 is located at the front end of the protrusion 112. When the bearing 12 pushes the flexible wheel bushing 13 to deform, the supporting force of the bearing 12 on the flexible wheel bushing 13 is along the axial direction of the protrusion 112. At the same time, the two protrusions 112 are respectively located at the two ends of the cam 11. At this time, the bearing 12 has a better supporting effect on the flexible wheel bushing 13, which is beneficial to improve the stability of the wave generator 1. Figures 4 to 6 In another embodiment of the present invention, there is provided a cam 11 with two stages, and each protrusion 112 is provided with two mounting shafts 113, by increasing the supporting area of ​​the flexspline bushing 13 near the protrusion 112, the flexspline bushing 13 produces stable topographic deformation, and the two mounting shafts 113 are evenly arranged, that is, the two mounting shafts 113 are symmetrically distributed along the axis of the protrusion 112, so that the bearings 12 are evenly distributed on the protrusion 112, and the supporting force of the flexspline bushing 13 is more uniform and stable, which is beneficial to improving the durability of the wave generator 1. When there are more than two mounting shafts 113 on the same protrusion 112, the multiple mounting shafts 113 are evenly distributed along the protruding edge of the protrusion 112, and the overall distribution position of all the mounting shafts 113 is symmetrical along the axis of the protrusion 112. Through such an arrangement, the bearing 12 mounted on the mounting shaft 113 can support the flexible wheel bushing 13 more evenly, and can be more stable when pushing the flexible wheel bushing 13 to deform, thereby improving the running stability and accuracy of the wave generator 1.

[0057] Combination Figure 3 and Figure 6 In a preferred case, the mounting shaft 113 includes a first shaft 113a and a second shaft 113b, the first shaft 113a is arranged on the first surface of the cam 11, and the second shaft 113b is arranged on the second surface of the cam 11. In the wave generator 1, the connection length of the flexwheel bushing 13 and the steel wheel of the harmonic reducer 1030 will directly affect the overall stability of the harmonic reducer 1030. In order to increase the connection length between the flexwheel bushing 13 and the flexwheel, it is necessary to increase the overall height of the flexwheel bushing 13. When the cam 11 is mounted on the inner ring of the flexwheel bushing 13, the mounting shaft 113 is arranged on both surfaces of the cam 11 to improve the support effect of the flexwheel bushing 13. Compared with the bearing 12 arranged on one side of the cam 11, the bearing 12 is arranged on both sides, so that the axial deformation of the flexwheel bushing 13 is more stable, thereby improving the contact between the flexwheel bushing 13 and the flexwheel and thereby improving the transmission effect of the flexwheel and the steel wheel.

[0058] The specific positions of the first shaft 113a and the second shaft 113b on the first surface and the second surface of the cam 11 are not limited here, and it can be satisfied that after the shaft 113 bearings are installed on the first shaft 113a and the second shaft 113b, the bearings 12 abut against the flexible wheel bushing 13 and make the flexible wheel bushing 13 and the flexible wheel reliably contact. In a preferred case, the first shaft 113a and the second shaft 113b are arranged in a one-to-one correspondence. Through such an arrangement, the bearings 12 on both sides of the cam 11 correspond to the supporting positions on the inner side of the flexible wheel bushing 13. During the deformation process of the flexible wheel bushing 13, the deformation positions of the flexible wheel bushing 13 on both sides of the cam 11 are consistent, which further promotes the stability of the wave generator 1 and avoids the inadequate engagement between the flexible wheel bushing 13 and the steel wheel, thereby achieving the effect of improving the accuracy of the harmonic reducer 1030 and increasing the service life of the harmonic reducer 1030.

[0059] Another aspect of the present invention provides a harmonic reducer 1030, comprising: a steel wheel assembly 1031, a flexspline, and a wave generator 1, wherein the flexspline bushing 13 of the wave generator 1 abuts against the flexspline.

[0060] The wave generator 1 causes the flexible wheel and the steel wheel assembly 1031 to mesh and rotate, and the meshing tooth difference between the flexible wheel and the steel wheel assembly 1031 generates a moving variable, which causes the flexible wheel bushing 13 to produce periodic deformation, thereby reducing the wear of the wave generator 1 and improving the transmission effect. The harmonic reducer 1030 drives the flexible wheel to rotate through the wave generator 1, and the flexible wheel meshes with the steel wheel assembly 1031, thereby driving the steel wheel assembly 1031 to rotate. The specific structural form of the steel wheel assembly 1031 is not limited here, nor is the specific method for the harmonic reducer 1030 to achieve deceleration. Optionally, by setting the number of internal teeth of the steel wheel assembly 1031 and the difference in the number of internal teeth between the upper and lower parts of the steel wheel assembly 1031, the moving variable generated by the meshing tooth difference between the flexible wheel and the steel wheel assembly 1031 is used to achieve a deceleration effect.

[0061] Combination Figure 7Another aspect of the present invention provides a mechanical arm joint 1000, which includes a housing 1010, a motor assembly 1020, a harmonic reducer 1030 and an output flange 1040; the motor assembly 1020 is arranged in the housing 1010, and the motor assembly 1020 drives the output flange 1040 to rotate through the harmonic reducer 1030; the harmonic reducer 1030 includes a steel wheel assembly 1031 and a wave generator 1, and the wave generator 1 is installed to the inner periphery of the flexible wheel. The flexible wheel is driven to move by the wave generator 1, and the outer group of the flexible wheel is meshed with the inner ring of the steel wheel assembly 1031, so as to achieve the effect of reducing the movement of the output flange 1040 and increase the torque. By such a setting, in the harmonic reducer 1030 on the mechanical arm joint 1000, the above-mentioned wave generator 1 is adopted, the motor assembly 1020 drives the cam 11 to rotate, the bearing 12 on the cam 11 pushes the flexible wheel to deform through the flexible wheel bushing 13, and the outer periphery of the flexible wheel is engaged with the inner ring of the steel wheel assembly 1031, so that the steel wheel assembly 1031 moves and drives the output flange 1040 to rotate. The wave generator 1 is operated more stably to ensure the output accuracy of the harmonic reducer 1030; the conventional bearing 12 in the wave generator 1 is set to replace the flexible bearing, so as to improve the strength and rigidity of the wave generator 1, ensure the stability and reliability of the harmonic reducer 1030, and thus improve the stability and service life of the mechanical arm joint 1000.

[0062] The specific structure of the motor assembly 1020 is not limited here, and it only needs to be able to drive the harmonic reducer 1030 to operate. The specific structure of the harmonic reducer 1030 is also not limited, and it only needs to be able to reduce the speed of the output flange 1040 through the harmonic reducer 1030, thereby increasing the output torque. In a preferred case, the motor assembly 1020 includes a drive plate 1021, a motor stator 1022 and a motor rotor 1023, the motor stator 1022 is fixedly connected to the inner side of the housing 1010, and the harmonic reducer 1030 also includes a camshaft 1032, the camshaft 1032 is fixedly connected to the motor rotor 1023, the drive plate 1021 drives the motor rotor 1023 to drive the camshaft 1032 to rotate, and the camshaft 1032 is fixedly connected to the cam 11. The connection method between the camshaft 1032 and the cam 11 is not limited here. A mounting hole for the camshaft 1032 can be set on the cam 11, and the camshaft 1032 is connected by snapping or bolting through the mounting hole. The camshaft 1032 and the cam 11 can also be integrally formed to improve the integrity of the harmonic reducer 1030, so that the transmission effect of the camshaft 1032 and the cam 11 in the harmonic reducer 1030 is better. During the operation of the mechanical arm joint 1000, the motor rotor 1023 drives the camshaft 1032 to rotate, thereby realizing the rotation of the cam 11. The fixedly connected motor rotor 1023 and camshaft 1032 are conducive to improving the stability of the transmission of the motor assembly 1020 to the wave generator 1. At the same time, the camshaft 1032 is fixedly connected to the cam 11, which further makes the rotation of the cam 11 more stable and controllable.

[0063] In a preferred case, the steel wheel assembly 1031 includes a first steel wheel 1031a and a second steel wheel 1031b, the first steel wheel 1031a is fixedly connected to the housing 1010, the second steel wheel 1031b is fixedly connected to the output flange 1040, the flexible wheel bushing 13 is connected to the inner ring of the flexible wheel, the outer ring of the flexible wheel is connected to the inner ring of the first steel wheel 1031a through gear meshing, the outer ring of the flexible wheel is connected to the inner ring of the second steel wheel 1031b through gear meshing, the number of teeth of the inner ring of the first steel wheel 1031a is different from the number of teeth of the inner ring of the second steel wheel 1031b, and the number of teeth of the outer ring of the flexible wheel is the same as the number of teeth of the inner ring of the first steel wheel or the second steel wheel. The connection method of the first steel wheel 1031a and the housing 1010 is not limited here, nor is the connection method of the second steel wheel 1031b and the output flange 1040, which can be screwed, clamped or bonded. It should be noted that the specific number of inner ring teeth of the first steel wheel 1031a and the number of inner ring teeth of the second steel wheel 1031b are not limited here. It can satisfy the different numbers of parts of the two and realize the rotation difference between the first steel wheel 1031a and the second steel wheel 1031b. The number of inner ring teeth of the first steel wheel 1031a can be greater than the number of inner ring teeth of the second steel wheel 1031b, or the number of inner ring teeth of the first steel wheel 1031a can be greater than the number of inner ring teeth of the second steel wheel 1031b. There is no restriction on the outer ring teeth number of the flexible pulley being the same as the inner ring teeth number of the first steel wheel 1031a, or the outer ring teeth number of the flexible pulley being the same as the inner ring teeth number of the second steel wheel 1031b. With such a configuration, the flexible pulley drives the first steel wheel 1031a and the second steel wheel 1031b to rotate. The inner ring teeth number of the first steel wheel 1031a is different from the inner ring teeth number of the second steel wheel 1031b, so that when the flexible pulley drives the first steel wheel 1031a and the second steel wheel 1031b, there is a speed difference between the first steel wheel 1031a and the second steel wheel 1031b, thereby achieving a deceleration effect.

[0064] In a preferred case, the robot arm joint 1000 also includes an output shaft 1050 disposed in the housing 1010, the output shaft 1050 is integrally formed with the output flange 1040 or connected through a connector, and the camshaft 1032 is sleeved on the output shaft 1050. Through such a configuration, the output shaft 1050 is disposed in the housing 1010, and the output flange 1040 is supported to make its movement more stable. At the same time, the output shaft 1050 can be used for routing, so that the overall appearance of the robot arm joint 1000 is neater and also plays a role in protecting the line. The connection method between the output shaft 1050 and the output flange 1040 is not limited here, and can be a fixed connection or integrally formed, in which case the output shaft 1050 rotates with the output flange 1040, or can be connected through a general bearing, the output shaft 1050 supports the output flange 1040, and the output flange 1040 rotates around the axis of the output shaft 1050. When the output shaft 1050 is set to be hollow, the interior of the output shaft 1050 is used for wiring. At this time, a threading hole that is colinear with the output shaft 1050 is reserved on the shell 1010 of the robot joint 1000. The communication or power supply line of the robot arm passes along the axis of the robot joint 1000, which is convenient for line storage and protection.

[0065] In a preferred case, the robot arm joint 1000 further includes an encoder 1060 disposed in the housing 1010, and the encoder 1060 is used to collect motion information of the camshaft 1032. Through such a setting, the encoder 1060 collects motion information of the camshaft 1032, and feeds back the current motion information to the upper system, and combines the actual motion of the output flange 1040 to improve the accuracy and response speed of motion control, thereby improving the stability of the robot arm joint 1000.

[0066] It should be understood that the above specific embodiments of the present invention are only used to illustrate or explain the principles of the present invention, and do not constitute a limitation of the present invention. Therefore, any modifications, equivalent substitutions, improvements, etc. made without departing from the spirit and scope of the present invention should be included in the protection scope of the present invention. In addition, the appended claims of the present invention are intended to cover all changes and modifications that fall within the scope and boundaries of the appended claims, or the equivalent forms of such scope and boundaries.

Claims

1. A wave generator, characterized in that: The wave generator (1) comprises: a cam (11), a bearing (12) and a flex spline bushing (13); The cam (11) is formed with a cam body (111) and at least two protrusions (112), each of the protrusions (112) is provided with at least one mounting shaft (113), the number of the bearings (12) corresponds to the number of the mounting shafts (113), the inner ring of the bearing (12) is adapted to be mounted on the mounting shaft (113), the outer ring of the bearing (12) is in contact with the flexible wheel bushing (13), the cam (11) rotates, driving the bearing (12) to revolve along the axial center point of the cam (11), the flexible wheel bushing (13) is used to reduce the wear of the bearing, and the flexible wheel bushing (13) produces periodic deformation.

2. The wave generator according to claim 1, characterized in that The protrusions (112) are symmetrically distributed along the center of the cam body (111).

3. The wave generator according to claim 2, characterized in that When each of the protruding portions (112) is provided with a mounting shaft (113), the mounting shaft (113) is arranged at an end portion close to the protruding portion (112); When a plurality of the mounting shafts (113) are provided on each of the protruding portions (112), the plurality of the mounting shafts (113) are evenly arranged at the ends of the protruding portions (112).

4. The wave generator according to claim 3, characterized in that The mounting shaft (113) comprises a first shaft (113a) and a second shaft (113b), wherein the first shaft (113a) is arranged on a first surface of the cam (11), and the second shaft (113b) is arranged on a second surface of the cam (11).

5. A harmonic reducer, characterized in that: The harmonic reducer comprises: a steel wheel assembly (1031), a flexspline, and a wave generator (1) as described in claims 1 to 4, wherein a flexspline bushing (13) of the wave generator (1) abuts against the flexspline.

6. A robotic arm joint, characterized in that: The mechanical arm joint (1000) comprises a housing (1010), a motor assembly (1020), a harmonic reducer (1030) and an output flange (1040); The motor assembly (1020) is disposed in the housing (1010), and the motor assembly (1020) drives the output flange (1040) to rotate via the harmonic reducer (1030); The harmonic reducer (1030) comprises a steel wheel assembly (1031), a flexible wheel and a wave generator (1), wherein the wave generator (1) is mounted on the inner circumference of the flexible wheel; The outer teeth of the flexible wheel mesh with the inner teeth of the steel wheel assembly (1031); The wave generator (1) comprises a wave generator (1) as claimed in any one of claims 1 to 4.

7. The mechanical arm joint according to claim 6, characterized in that: The motor assembly (1020) comprises a drive plate (1021), a motor stator (1022) and a motor rotor (1023); the motor stator (1022) is fixedly connected to the inner side of the housing (1010); the harmonic reducer (1030) further comprises a camshaft (1032); the camshaft (1032) is fixedly connected to the motor rotor (1023); the drive plate (1021) drives the motor rotor (1023) to drive the camshaft (1032) to rotate; and the camshaft (1032) is fixedly connected to the cam (11).

8. The mechanical arm joint according to claim 7, characterized in that: The steel wheel assembly (1031) comprises a first steel wheel (1031a) and a second steel wheel (1031b), wherein the first steel wheel (1031a) is fixedly connected to the housing (1010), and the second steel wheel (1031b) is fixedly connected to the output flange (1040), the flexible wheel bushing (13) is connected to the inner ring of the flexible wheel, the outer ring of the flexible wheel is connected to the inner ring of the first steel wheel (1031a) through tooth meshing, and the outer ring of the flexible wheel is connected to the inner ring of the second steel wheel (1031b) through tooth meshing, the number of teeth on the inner ring of the first steel wheel (1031a) is different from the number of teeth on the inner ring of the second steel wheel (1031b), and the number of teeth on the outer ring of the flexible wheel is the same as the number of teeth on the inner ring of the first steel wheel (1031a) or the second steel wheel (1031b).

9. The mechanical arm joint according to claim 8, characterized in that: The mechanical arm joint (1000) further comprises an output shaft (1050) disposed in the housing (1010); the output shaft (1050) is integrally formed with the output flange (1040) or connected via a connecting piece; and the camshaft (1032) is sleeved on the output shaft (1050).

10. The mechanical arm joint according to any one of claims 6 to 9, characterized in that: The mechanical arm joint (1000) further includes an encoder (1060) disposed in the housing (1010), and the encoder (1060) is used to collect motion information of the camshaft (1032).

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