A robot drive joint

Abstract

The utility model provides a kind of driving joint for robot, including shell, motor main body, motor driver, speed reduction mechanism and output flange.Cylindrical installation cavity is equipped in shell interior, motor main body and motor driver are all installed in installation cavity, and motor driver is integrated with encoder, for detecting the rotating position and speed of motor shaft.Speed reduction mechanism adopts two-stage planetary transmission structure, including sun gear shaft, sun gear, planet carrier, planet shaft, first and second planetary gears and first and second inner gear rings, can realize high speed reduction ratio and high torque density.Output flange is coaxially fixed connection with second inner gear ring, for output torque and rotational speed.The utility model structure is compact, and integrated degree is high, with transmission precision is high, bearing capacity is strong, it is easy to install maintenance and the like advantage, it is applicable to the demand of lightweight, high load driving joint in robot field.

Description

Technical Field

[0001] This utility model relates to the field of robotics, and more specifically, to a drive joint for a robot. Background Technology

[0002] Drive joints are the core power execution units of robots, and their performance directly determines the motion control accuracy, rated load capacity, and dynamic response speed of the entire machine. As industrial automation evolves towards high-precision production, intelligent manufacturing upgrades towards flexibility, and humanoid robots develop towards lightweight and high mobility, the industry has put forward multi-dimensional and stringent requirements for robot drive joints, including higher power density, larger reduction ratios, higher transmission efficiency, and better reliability.

[0003] As a key component for power conversion and transmission in drive joints, the performance of the reducer directly determines the overall performance of the drive system. Currently, the mainstream reducers in the robot drive field mainly include three types: harmonic reducers, RV reducers, and traditional planetary reducers. Harmonic reducers, with their compact structure and large single-stage reduction ratio, are widely used in light-load scenarios such as robot wrists and hands. However, their flexible wheels are prone to fatigue cracks due to long-term alternating stress, resulting in limited service life, and they generally suffer from low reverse transmission efficiency. RV reducers, characterized by high rigidity, high load-bearing capacity, and good motion stability, are often used in heavy-load critical parts such as robot bases and upper arms. However, they suffer from complex structures and high manufacturing costs, and it is difficult to simultaneously meet the requirements of structural miniaturization while pursuing a large reduction ratio. Traditional planetary reducers, while possessing advantages such as strong overload capacity, controllable cost, high forward and reverse transmission efficiency, and good structural stability, have relatively low torque density and reduction ratio, and are affected by tooth backlash errors, making it difficult to simultaneously achieve both transmission accuracy and transmission efficiency.

[0004] Furthermore, in current robot drive joints, motors, reducers, and drivers are mostly designed for independent, separate installation. This not only results in larger overall joint size and weight but also leads to low installation efficiency and cumbersome maintenance, severely hindering the development of robots towards miniaturization and lightweighting. Utility Model Content

[0005] The main technical problem addressed by this application is that the existing robot drive joints have a large volume due to their split design, low reduction ratio and torque density of traditional planetary reducers, and insufficient transmission accuracy. To overcome the above-mentioned defects of the prior art, this application provides a drive joint for robots.

[0006] This application provides a drive joint for a robot, comprising: The housing has a cylindrical mounting cavity inside; The motor body is installed in the mounting cavity, and the output end of the motor body is provided with a motor shaft, which is coaxially arranged with the mounting cavity; A motor driver, which is installed in the mounting cavity and is used to drive the rotation of the motor shaft, has an integrated encoder for detecting the rotational position and speed of the motor shaft; A reduction mechanism includes a sun gear shaft, a sun gear, a planet carrier, planet shafts, first planet gears, second planet gears, a first internal gear ring, and a second internal gear ring. The sun gear shaft is coaxially and fixedly connected to the motor shaft. The sun gear is coaxially and fixedly connected to the outer wall of the sun gear shaft. The planet carrier is coaxially and rotatably connected to the sun gear shaft. Multiple planet shafts are provided and evenly distributed circumferentially on the planet carrier. The planet shafts are rotatably connected to the planet carrier. Each planet shaft has a first planet gear and a second planet gear coaxially and fixedly connected. The first internal gear ring is coaxially and fixedly connected in a mounting cavity. The second internal gear ring is coaxially and rotatably connected in a mounting cavity. The first planet gear meshes with the sun gear and the first internal gear ring respectively, and the second planet gear meshes with the second internal gear ring. An output flange is coaxially fixedly connected to the second internal gear ring. The end face of the output flange facing away from the second internal gear ring has multiple connection holes, which are used for torque and speed output.

[0007] Compared with existing technologies, the robot drive joint proposed in this application has the following advantages: A two-stage planetary transmission structure consisting of a sun gear, a first planetary gear, and a first internal gear ring, and a second planetary gear and a second internal gear ring, significantly improves the reduction ratio and torque density compared to traditional single-stage planetary reducers. This allows it to meet the high-load, high-reduction-ratio power requirements of robots, solving the problems of low torque density and insufficient reduction ratio in traditional planetary reducers. The motor body, motor driver, reduction mechanism, and output flange are integrated into the mounting cavity of the same housing, replacing the existing split design. This significantly reduces the overall size and weight of the drive joint, meeting the needs of lightweight and miniaturized robot development, while also reducing installation complexity and improving assembly efficiency. An encoder integrated on the motor driver can detect the rotational position and speed of the motor shaft in real time, providing precise position and speed feedback for robot motion control, reducing transmission errors, improving the motion control accuracy of the drive joint, and solving the problem of insufficient feedback accuracy in existing drive joints affecting the overall control performance. Multiple connection holes on the output flange end face can be directly connected to the robot's actuators to achieve stable transmission of torque and speed. It has strong adaptability, simplifies the connection structure of the power output end, and improves the compatibility of the drive joint with other robot components.

[0008] In one possible implementation, the housing includes a casing and an end cover. The end cover is bolted to the end of the casing, and the motor driver is positioned close to the end cover. The end cover has a cable pass-through hole for the motor driver's wiring cable. Compared to existing technologies, the end cover is bolted to the end of the casing, allowing for quick disassembly to inspect the internal structure of the housing. Compared to welded or one-piece casings, this significantly reduces maintenance difficulty and improves subsequent maintenance efficiency. The motor driver's proximity to the end cover, with its pre-drilled cable pass-through hole, facilitates centralized routing and organization of the motor driver's wiring cable, preventing signal interference or wear caused by messy cables, improving wiring standardization, reducing cable inspection difficulty, and ensuring circuit connection stability.

[0009] In one possible implementation, the motor body includes a motor stator and a motor rotor. The motor stator is interference-fitted to the inner wall of the housing, and the motor rotor is rotatably connected to the inner side of the motor stator via a motor shaft. The motor shaft is rotatably connected to the housing via a rotary bearing, and the windings of the motor stator are electrically connected to the motor driver. Compared with the prior art, the motor stator is fixed to the inner wall of the housing via an interference fit, which can prevent the stator from loosening or shifting when the motor is running at high speed, reduce vibration and noise, improve the motor's operational stability, and extend the motor's service life. The motor rotor is rotatably connected to the inner side of the stator via the motor shaft and rotary bearing, which significantly reduces the rotor's rotational resistance, reduces frictional losses, and improves the motor's transmission efficiency. At the same time, the stator windings are directly electrically connected to the motor driver, shortening the current transmission path, reducing line losses, ensuring the stability of the motor's power input, and avoiding power fluctuations caused by line problems.

[0010] In one possible implementation, the housing is provided with a mounting bracket for securing the drive circuit board of the motor driver. Compared with the prior art, the mounting bracket on the housing provides dedicated mounting support for the drive circuit board of the motor driver, which can prevent the drive circuit board from loosening or shifting in the vibration environment of robot operation, ensuring the structural integrity and operational stability of the drive circuit board, thereby ensuring the normal operation of the motor driver and reducing drive failures caused by loose circuit boards.

[0011] In one possible implementation, the encoder includes a detection component and a rotating component. The detection component is fixedly mounted on a drive circuit board, and the rotating component is fixedly connected to a motor shaft. Compared to existing technologies, the encoder's detection component is fixed to the drive circuit board, and the rotating component is fixed to the motor shaft, ensuring synchronous movement between the encoder and the motor shaft. This reduces detection delay and errors, significantly improves the detection accuracy of the motor shaft's rotational position and speed, provides more reliable feedback data for precise robot control, and solves the detection deviation problem caused by misalignment in existing encoders. The direct connection between the encoder and the drive circuit board / motor shaft eliminates the need for additional transmission components, simplifying the detection system structure, reducing component complexity and failure risk, and improving the reliability of the detection system.

[0012] In one possible implementation, the output flange is bolted to the end of the second internal gear ring. Compared to existing technologies, the bolted connection between the output flange and the second internal gear ring ensures a secure connection that prevents relative slippage during high-torque, high-speed transmission, guaranteeing lossless power transmission. The bolted connection is also detachable, facilitating the replacement of the output flange according to the needs of different robot actuators, improving the adaptability of the drive joints, reducing the difficulty of replacing a damaged output flange, and lowering maintenance costs.

[0013] In one possible implementation, the outer wall of the planetary shaft is provided with an external spline, and both the first and second planetary gears are provided with shaft holes through which the planetary shaft passes. The inner wall of the shaft hole is provided with an internal spline, and the internal spline is fixedly engaged with the external spline. Compared with the prior art, the planetary shaft and planetary gears are fixed by the engagement of internal and external splines. Compared with ordinary flat key connections, splines have a larger contact area and stronger load-bearing capacity, which can withstand the high torque load in a two-stage planetary transmission, reduce local wear at the connection points, extend the service life of the reduction mechanism, and solve the problems of insufficient load-bearing capacity and easy wear of traditional key connections. Spline engagement can ensure the precise coaxiality of the planetary shaft and planetary gears, avoid poor tooth surface meshing caused by coaxiality deviation, reduce transmission errors, improve the transmission accuracy of the reduction mechanism, and thus ensure the stability of the output power of the drive joint.

[0014] In one possible implementation, the planetary shaft is rotatably connected to the planet carrier via a single-row needle roller bearing, and the planet carrier is rotatably connected to the sun gear shaft via a deep groove ball bearing. Compared with the prior art, the planetary shaft is connected to the planet carrier via a single-row needle roller bearing. The needle roller bearing has a small radial dimension and high load-bearing capacity, which is suitable for the compact internal space of the planet carrier, while significantly reducing the rotational resistance of the planetary shaft and improving the rotational flexibility of the planetary gears. The planet carrier is connected to the sun gear shaft via a deep groove ball bearing, which can simultaneously bear radial and axial loads, preventing the planet carrier from tilting or jamming during rotation, reducing frictional loss, and improving the overall transmission efficiency of the reduction mechanism.

[0015] In one possible implementation, the second internal gear ring is rotatably connected to the inner wall of the housing via a crossed roller bearing. Compared with the prior art, the crossed roller bearing has the characteristics of high rigidity, high precision, and strong load-bearing capacity. It can effectively withstand the radial and axial loads generated by the second internal gear ring during rotation (especially the combined loads brought by the two-stage planetary transmission), avoid deformation or displacement of the second internal gear ring, and ensure the transmission accuracy of the reduction mechanism.

[0016] In one possible implementation, the first internal gear ring is fixedly connected to the inner wall of the housing by bolts. Compared with the prior art, the first internal gear ring is fixed to the inner wall of the housing by bolts, serving as the fixed end of the two-stage planetary transmission. This ensures that it does not loosen or shift when meshing with the first planetary gear, avoiding meshing errors caused by the offset of the first internal gear ring, ensuring the accuracy of the two-stage planetary transmission, and reducing transmission losses. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the overall structure of this application. Figure 1 ; Figure 2 This is a schematic diagram of the overall structure of this application. Figure 2 ; Figure 3 A cross-section of this application Figure 1 ; Figure 4 A cross-section of this application Figure 2 ; Figure 5 A cross-section of this application Figure 3 ; Figure 6 This is a schematic diagram of the planetary carrier structure; Figure 7 This is a schematic diagram of the planetary axis structure; Explanation of reference numerals in the attached figures: 1. Housing; 11. Shell; 12. End cover; 121. Wire hole; 2. Motor body; 21. Motor stator; 22. Motor rotor; 3. Motor shaft; 31. Rotary bearing; 4. Motor driver; 5. Encoder; 6. Reduction mechanism; 61. Sun gear shaft; 62. Sun gear; 63. Planetary carrier; 64. Planetary shaft; 641. External spline; 642. Single-row needle roller bearing; 65. First planetary gear; 66. Second planetary gear; 67. First internal gear ring; 68. Second internal gear ring; 681. Crossed roller bearing; 7. Output flange; 71. Connecting hole; 8. Mounting base. Detailed Implementation

[0018] First, those skilled in the art should understand that these embodiments are merely used to explain the technical principles of the embodiments of this application and are not intended to limit the scope of protection of the embodiments of this application. Those skilled in the art can make adjustments as needed to adapt to specific application scenarios.

[0019] In the description of the embodiments of this application, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of this application based on the specific circumstances.

[0020] In the embodiments of this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0021] The present application will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0022] See Figures 1 to 7 This application discloses a drive joint for a robot, including: a housing 1, a motor body 2, a motor driver 4, a reduction mechanism 6, and an output flange 7.

[0023] The housing 1 is made of cast aluminum alloy and has a precisely machined cylindrical mounting cavity inside. The diameter and length of the mounting cavity are determined according to the dimensions of the motor body 2 and the reduction mechanism 6. The inner wall of the mounting cavity is precision ground to ensure coaxiality with the internal components.

[0024] The main body 2 is a brushless servo motor, which is installed and fixed inside the mounting cavity. The motor shaft 3 at its output end is made of high-strength steel and is coaxially arranged with the mounting cavity.

[0025] The motor driver 4 is installed inside the mounting cavity, located on the rear side of the motor body 2 away from the motor shaft 3, driving the rotation of the motor shaft 3. The motor driver 4 integrates an encoder 5, which can acquire the rotational position and speed signals of the motor shaft 3 in real time and feed these signals back to the drive circuit board of the motor driver 4 to achieve closed-loop control. The integrated design of the encoder 5 eliminates the installation space required for a separate encoder 5, improves the integration of the drive joint, and solves the problem of the large size of traditional separate designs.

[0026] The reduction mechanism 6 includes a sun gear shaft 61, a sun gear 62, a planet carrier 63, planet shafts 64, a first planet gear 65, a second planet gear 66, a first internal gear ring 67, and a second internal gear ring 68. One end of the sun gear shaft 61 is coaxially fixed to the motor shaft 3 via an interference fit. The sun gear 62 is integrally and coaxially machined in the middle of the sun gear shaft 61, meshing with the first planet gear 65. The planet carrier 63 is coaxially supported on the other end of the sun gear shaft 61 by deep groove ball bearings, allowing relative rotation. Four planet shafts 64 are provided, evenly distributed circumferentially on the planet carrier 63. Each planet shaft 64 is rotatably connected to the planet carrier 63 via a single-row needle roller bearing 642. Each planet shaft 64 has a first planet gear 65 and a second planet gear 66 press-fitted at intervals to achieve differential reduction. The first internal gear ring 67 is coaxially fixed in an annular groove on the inner wall of the housing 1 by bolts, and its teeth mesh with the first planet gear 65. The second internal gear ring 68 is coaxially supported on the inner wall of the housing 1 by a cross roller bearing 681, and can rotate relative to it. Its tooth profile meshes with the second planetary gear 66.

[0027] The output flange 7 is disc-shaped and is bolted to the end face of the second internal gear ring 68. Multiple threaded connection holes 71 are evenly distributed on the flange end face for connecting robot actuators.

[0028] In this embodiment, the housing 1 includes a housing 11 and an end cover 12, which is fixedly connected to the end of the housing 11 by bolts. The motor driver 4 is disposed close to the end cover 12, which shortens the wiring length between the motor driver 4 and the motor stator 21, reducing line loss and electromagnetic interference. A wire through hole 121 is provided on the end cover 12 for the wiring cable of the power supply driver 4 to pass through.

[0029] In this embodiment, the motor body 2 includes a motor stator 21 and a motor rotor 22. The motor stator 21 is made of laminated silicon steel sheets, and its outer wall is pressed into the housing 11 by an interference fit. The motor rotor 22 is coaxially fixed on the motor shaft 3, and the motor shaft 3 is rotatably connected to the housing 11 through a rotary bearing 31, so that the motor rotor 22 is rotatably located inside the motor stator 21. The windings of the motor stator 21 are electrically connected to the motor driver 4, realizing precise control of the speed and torque of the motor shaft 3.

[0030] In this embodiment, a mounting base 8 is installed on the side of the housing 11 facing the end cover 12, and its surface has mounting threaded holes. The drive circuit board of the motor driver 4 is fixed to the mounting base 8 by screws.

[0031] In this embodiment, the encoder 5 includes a detection component and a rotation component. The detection component is a photoelectric sensing module integrated on the drive circuit board. The rotation component is a code disk, which is fixed to the end of the motor shaft 3 by a set screw and rotates coaxially with the motor shaft 3. The distance between the code disk and the photoelectric sensing module is controlled to ensure stable signal acquisition.

[0032] In this embodiment, the outer wall of the planetary shaft 64 is machined with an involute external spline 641. The length of the external spline 641 is greater than the total thickness of the first planetary gear 65 and the second planetary gear 66. The spline surface is subjected to high-frequency quenching treatment to improve wear resistance. The inner walls of the shaft holes of the first planetary gear 65 and the second planetary gear 66 are machined with internal splines that are adapted to the external spline 641 of the planetary shaft 64. The surface of the internal spline is also subjected to high-frequency quenching treatment to ensure the meshing accuracy with the external spline 641. After the splines are engaged, they achieve gapless fixation.

[0033] This embodiment describes a drive joint for a robot. When the drive joint is in operation, the motor driver 4 drives the motor body 2 within the housing 1 to rotate, and the motor shaft 3 rotates. An encoder 5 integrated into the motor driver 4 detects the rotational position and speed of the motor shaft 3 in real time, and the feedback data enables closed-loop control. Power is transmitted via a sun gear shaft 61 coaxially connected to the motor shaft 3. The sun gear 62 drives the first planetary gear 65. Because the first internal gear ring 67 is fixed to the housing 1, the first planetary gear 65, through meshing, drives the planetary shaft 64 and planet carrier 63 to rotate. The second planetary gear 66 on the planetary shaft 64 then drives the second internal gear ring 68, forming a two-stage planetary transmission, significantly improving the reduction ratio and torque density. Finally, the second internal gear ring 68 drives the coaxially fixed output flange 7, transmitting torque and speed to the robot's execution components through the flange end face connection hole 71.

[0034] The beneficial effects of this application include: I. The two-stage planetary transmission structure significantly improves the reduction ratio and torque density, solving the problems of low torque density and insufficient reduction ratio of traditional planetary reducers, and adapting to the high-load power requirements of robots.

[0035] 2. The motor body 2, motor driver 4, reduction mechanism 6, etc. are integrated into the same housing 1 mounting cavity, replacing the split design, significantly reducing the joint volume and weight, improving assembly efficiency, and meeting the development needs of lightweight and miniaturized robots.

[0036] Third, the motor driver 4 integrates an encoder 5, which can accurately detect the rotational position and speed of the motor shaft 3 in real time, reduce transmission errors, improve the motion control accuracy of the drive joints, and ensure the overall control performance of the robot.

[0037] IV. The output flange 7 is bolted to the second internal gear ring 68 and has a connection hole 71 to adapt to different actuators, simplify the power output connection, and reduce the cost of flange replacement and maintenance. The design of the planetary shaft 64 spline meshing and the second internal gear ring 68 using crossed roller bearings 681 improves the load-bearing capacity and transmission accuracy, reduces wear, and extends the service life.

[0038] In the description of the embodiments of this application, it should be noted that the terms "inner" and "outer" and other terms indicating direction or positional relationship are based on the direction or positional relationship shown in the drawings. This is only for the convenience of description and does not indicate or imply that the device or component must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation of this application.

[0039] In the description of this application, the references to terms such as "an embodiment," "some embodiments," "in this embodiment," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in a suitable manner in any one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0040] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A driving joint for a robot, characterized by, include: The housing has a cylindrical mounting cavity inside; The motor body is installed in the mounting cavity, and the output end of the motor body is provided with a motor shaft, which is coaxially arranged with the mounting cavity; A motor driver, which is installed in the mounting cavity and is used to drive the rotation of the motor shaft, has an integrated encoder for detecting the rotational position and speed of the motor shaft; A reduction mechanism includes a sun gear shaft, a sun gear, a planet carrier, planet shafts, first planet gears, second planet gears, a first internal gear ring, and a second internal gear ring. The sun gear shaft is coaxially and fixedly connected to the motor shaft. The sun gear is coaxially and fixedly connected to the outer wall of the sun gear shaft. The planet carrier is coaxially and rotatably connected to the sun gear shaft. Multiple planet shafts are provided and evenly distributed circumferentially on the planet carrier. The planet shafts are rotatably connected to the planet carrier. Each planet shaft has a first planet gear and a second planet gear coaxially and fixedly connected. The first internal gear ring is coaxially and fixedly connected in a mounting cavity. The second internal gear ring is coaxially and rotatably connected in a mounting cavity. The first planet gear meshes with the sun gear and the first internal gear ring respectively, and the second planet gear meshes with the second internal gear ring. An output flange is coaxially fixedly connected to the second internal gear ring. The end face of the output flange facing away from the second internal gear ring has multiple connection holes, which are used for torque and speed output.

2. The drive joint for a robot according to claim 1, characterized in that, The housing includes a housing and an end cover. The end cover is fixedly connected to the end of the housing by bolts. The motor driver is located near the end cover. The end cover has a wire hole through which the wiring cable of the motor driver passes.

3. The drive joint for a robot according to claim 2, characterized in that, The motor body includes a motor stator and a motor rotor. The motor stator is interference-fitted into the inner wall of the housing. The motor rotor is rotatably connected to the inner side of the motor stator via a motor shaft. The motor shaft is rotatably connected to the housing via a rotary bearing. The windings of the motor stator are electrically connected to the motor driver.

4. The drive joint for a robot according to claim 2, characterized by The housing is provided with a mounting base, which is used to fix the drive circuit board of the motor driver.

5. The drive joint for a robot according to claim 4, characterized in that, The encoder includes a detection component and a rotating component. The detection component is fixedly mounted on the drive circuit board, and the rotating component is fixedly connected to the motor shaft.

6. The drive joint for a robot according to claim 1, characterized by The output flange is bolted to the end of the second internal gear ring.

7. The drive joint for a robot according to claim 1, characterized in that, The outer wall of the planetary shaft is provided with an external spline, and the first planetary gear and the second planetary gear are each provided with a shaft hole for the planetary shaft to pass through. The inner wall of the shaft hole is provided with an internal spline, and the internal spline is fixedly engaged with the external spline.

8. The drive joint for a robot according to claim 1, characterized in that, The planetary shaft is rotatably connected to the planet carrier via a single-row needle roller bearing, and the planet carrier is rotatably connected to the sun gear shaft via a deep groove ball bearing.

9. The drive joint for a robot according to claim 2, characterized in that, The second internal gear ring is rotatably connected to the inner wall of the housing via a crossed roller bearing.

10. The drive joint for a robot according to claim 2, characterized in that, The first internal gear ring is fixedly connected to the inner wall of the housing by bolts.

Images