阅读说明：本技术 一体化外转子机械臂关节 (Integrated outer rotor mechanical arm joint ) 是由 王红兵 李国才 王庆国 于 2021-09-10 设计创作，主要内容包括：本发明公开了一种一体化外转子机械臂关节,包括关节壳体,所述关节壳体内安装有外转子电机,所述外转子电机包括固定在所述关节壳体上的电机定子,所述电机定子外配合安装有作为关节输入的电机转子,所述电机转子作为减速器组件的输入端,所述电机转子的外周设置有N个相位角不同的偏心安装位,相邻两所述偏心安装位之间的相位角呈360°/N,N≥2；所述减速器组件安装在所述电机转子外周与所述关节壳体之间,所述减速器组件对应安装在所述电机转子的偏心安装位处,所述减速器组件的输出端安装有作为关节输出的行星输出架,所述电机转子与所述行星输出架之间安装有编码器组件；本发明具有结构紧凑、布置合理、体积小、输出扭矩大、装配方便、制造成本低等优点,使用范围较广。(The invention discloses an integrated outer rotor mechanical arm joint which comprises a joint shell, wherein an outer rotor motor is arranged in the joint shell, the outer rotor motor comprises a motor stator fixed on the joint shell, a motor rotor used as joint input is arranged outside the motor stator in a matched mode, the motor rotor is used as the input end of a speed reducer assembly, N eccentric mounting positions with different phase angles are arranged on the periphery of the motor rotor, the phase angle between every two adjacent eccentric mounting positions is 360 degrees/N, and N is more than or equal to 2; the reducer assembly is installed between the periphery of the motor rotor and the joint shell, the reducer assembly is correspondingly installed at an eccentric installation position of the motor rotor, a planetary output frame serving as joint output is installed at the output end of the reducer assembly, and an encoder assembly is installed between the motor rotor and the planetary output frame; the invention has the advantages of compact structure, reasonable arrangement, small volume, large output torque, convenient assembly, low manufacturing cost and the like, and has wider application range.)

1. Integration outer rotor arm joint, including joint housing, its characterized in that: an outer rotor motor is installed in the joint shell and comprises a motor stator fixed on the joint shell, a motor rotor used as joint input is installed outside the motor stator in a matched mode, the motor rotor is used as an input end of a speed reducer assembly, N eccentric installation positions with different phase angles are arranged on the periphery of the motor rotor, the phase angle between every two adjacent eccentric installation positions is 360 degrees/N, and N is larger than or equal to 2; the reducer subassembly is installed motor rotor periphery with between the joint casing, the reducer subassembly corresponds to be installed motor rotor's eccentric installation position department, the planet output frame of joint output is installed as to the output of reducer subassembly, motor rotor with install the encoder subassembly between the planet output frame.

2. The integrated outer rotor mechanical arm joint as claimed in claim 1, wherein: the reducer assembly comprises transmission gears which are respectively rotatably arranged on the eccentric mounting positions, the peripheries of all the transmission gears are meshed with a fixed gear ring, and the fixed gear ring is fixedly arranged on the joint shell.

3. The integrated outer rotor mechanical arm joint as claimed in claim 2, wherein: the planet output frame comprises planet carrier upper covers and planet carrier lower covers which are coaxially matched and arranged on the outer end surfaces of the two sides of all the transmission gears, the planet carrier upper covers are used as joint outputs, and the encoder assembly is connected to the planet carrier lower covers; the planet carrier upper cover with be connected with the locking fixing device including all drive gear installations between the planet carrier lower cover, still be provided with between planet carrier upper cover and the planet carrier lower cover and run through each drive gear's moment transmission device.

4. The integrated outer rotor mechanical arm joint as claimed in claim 3, wherein: the anti-loosening fixing device comprises anti-loosening bolts fixed by threads of the upper cover of the planet carrier and the lower cover of the planet carrier, the anti-loosening bolts are formed by the lower cover of the planet carrier through all the transmission gear threads are connected to the upper cover of the planet carrier and all the transmission gear threads are provided with positioning sleeves between the transmission gear threads and the anti-loosening bolts, and two ends of each positioning sleeve are respectively abutted against the upper cover of the planet carrier and the lower cover of the planet carrier.

5. The integrated outer rotor mechanical arm joint as claimed in claim 3, wherein: the torque transmission device comprises a torque transmission pin shaft, the torque transmission pin shaft penetrates through all the transmission gears, two ends of the torque transmission pin shaft are respectively positioned on the upper cover of the planet carrier and the lower cover of the planet carrier, and a pin shaft sleeve is respectively arranged between each transmission gear and the torque transmission pin shaft.

6. The integrated outer rotor mechanical arm joint as claimed in claim 1, wherein: the encoder assembly comprises a code disc element and a code reading element, the code disc element comprises a code disc outer ring plate and a code disc inner ring plate which can rotate respectively, the code disc outer ring plate is coaxially sleeved outside the code disc inner ring plate, the code disc outer ring plate is fixed on the planet output frame, and the code disc inner ring plate is fixedly arranged on the motor rotor; the code reading element is coaxially fixed on one side of the code disc element and corresponds to the code disc outer ring plate and the code disc inner ring plate, and the code reading element is correspondingly fixed on the joint shell.

7. The integrated outer rotor mechanical arm joint as claimed in claim 6, wherein: the outer ring plate of the code disc and the inner ring plate of the code disc are positioned on the same plane.

8. The integrated outer rotor mechanical arm joint as claimed in claim 1, wherein: and a driving assembly corresponding to the encoder assembly is further installed in the joint shell.

Technical Field

The invention relates to the technical field of mechanical arm joints, in particular to an integrated outer rotor mechanical arm joint.

Background

With the rapid development of industrial automation technology, robots are increasingly gaining attention as important industrial automation equipment, and the application of robots is increasingly widespread. The robot technology mainly concentrates the latest research results of various technologies such as mechanical engineering, automatic control, artificial intelligence and the like, embodies the latest achievement of photoelectric integration, and is one of the fields with the most active scientific and technical development in the present day. The mechanical arm is an automatic mechanical device which is widely applied in the technical field of robots at present, plays an extremely important role in production and life, and in practical application, a plurality of industrial process links need the mechanical arm to carry out assembling and extracting operations. The mechanical arm can receive instructions and accurately position to a certain point on a three-dimensional (or two-dimensional) space to perform operation, and the labor efficiency can be greatly improved.

The mechanical arm joint is a core component of the mechanical arm, and the overall structure, the load capacity and the sensing capacity of the joint directly influence the overall operation level of the mechanical arm. At present, a motor, a speed reducer, an encoder, a brake and a driver are commonly adopted for a common mechanical arm joint to carry out a transmission mechanism connected in series. At present, the arm joint ubiquitous on the domestic market has heavy, the load capacity is low, bulky scheduling problem, has restricted further promotion of arm performance, and motor and reduction gear in the arm joint at present especially mainly adopt about side by side setting for the overall structure size of arm joint is great, and inside still need set up the power transmission to the reduction gear through the pivot with the motor, and is higher to the erection joint, and the installation degree of difficulty is great, leads to the application range of product less.

Disclosure of Invention

The invention aims to solve the technical problem of providing an integrated outer rotor mechanical arm joint which is compact in structure, reasonable in arrangement, small in size, large in output torque, convenient to assemble and low in manufacturing cost.

In order to solve the technical problems, the technical scheme of the invention is as follows: the integrated outer rotor mechanical arm joint comprises a joint shell, wherein an outer rotor motor is arranged in the joint shell, the outer rotor motor comprises a motor stator fixed on the joint shell, a motor rotor used as joint input is arranged outside the motor stator in a matched mode, the motor rotor is used as the input end of a speed reducer assembly, N eccentric mounting positions with different phase angles are arranged on the periphery of the motor rotor, the phase angle between every two adjacent eccentric mounting positions is 360 degrees/N, and N is more than or equal to 2; the reducer subassembly is installed motor rotor periphery with between the joint casing, the reducer subassembly corresponds to be installed motor rotor's eccentric installation position department, the planet output frame of joint output is installed as to the output of reducer subassembly, motor rotor with install the encoder subassembly between the planet output frame.

Preferably, the reducer assembly includes transmission gears rotatably mounted on the eccentric mounting positions, and a fixed gear ring is engaged with the outer peripheries of all the transmission gears and fixedly mounted on the joint housing.

As a preferable technical scheme, the planet output carrier comprises a planet carrier upper cover and a planet carrier lower cover which are coaxially matched and installed on the outer end faces of two sides of all transmission gears, the planet carrier upper cover is used as joint output, and the encoder assembly is connected to the planet carrier lower cover; the planet carrier upper cover with be connected with the locking fixing device including all drive gear installations between the planet carrier lower cover, still be provided with between planet carrier upper cover and the planet carrier lower cover and run through each drive gear's moment transmission device.

As an optimized technical scheme, the anti-loosening fixing device comprises anti-loosening bolts used for fixing the upper cover of the planet carrier and the lower cover of the planet carrier in a threaded mode, the anti-loosening bolts penetrate through the lower cover of the planet carrier and are connected to the upper cover of the planet carrier in a threaded mode, positioning sleeves are arranged between the transmission gears and the anti-loosening bolts, and two ends of each positioning sleeve are abutted to the lower cover of the planet carrier and the upper cover of the planet carrier respectively.

As a preferred technical scheme, the torque transmission device comprises a torque transmission pin shaft, the torque transmission pin shaft penetrates through all the transmission gears, two ends of the torque transmission pin shaft are respectively positioned on the upper cover of the planet carrier and the lower cover of the planet carrier, and a pin shaft sleeve is respectively arranged between each transmission gear and the torque transmission pin shaft.

As a preferred technical scheme, the encoder assembly comprises a code disc element and a code reading element, the code disc element comprises a code disc outer ring plate and a code disc inner ring plate which can rotate respectively, the code disc outer ring plate is coaxially sleeved outside the code disc inner ring plate, the code disc outer ring plate is fixed on the planet output frame, and the code disc inner ring plate is fixedly arranged on the motor rotor; the code reading element is coaxially fixed on one side of the code disc element and corresponds to the code disc outer ring plate and the code disc inner ring plate, and the code reading element is correspondingly fixed on the joint shell.

Preferably, the outer ring plate of the code wheel and the inner ring plate of the code wheel are located on the same plane.

Preferably, a driving assembly corresponding to the encoder assembly is further installed in the joint housing.

By adopting the technical scheme, the integrated outer rotor mechanical arm joint comprises a joint shell, wherein an outer rotor motor is arranged in the joint shell, the outer rotor motor comprises a motor stator fixed on the joint shell, a motor rotor used as joint input is arranged outside the motor stator in a matched mode, the motor rotor is used as the input end of a speed reducer assembly, N eccentric mounting positions with different phase angles are arranged on the periphery of the motor rotor, the phase angle between every two adjacent eccentric mounting positions is 360 degrees/N, and N is not less than 2; the reducer assembly is installed between the periphery of the motor rotor and the joint shell, the reducer assembly is correspondingly installed at an eccentric installation position of the motor rotor, a planetary output frame serving as joint output is installed at the output end of the reducer assembly, and an encoder assembly is installed between the motor rotor and the planetary output frame; the invention has the beneficial effects that:

1. according to the invention, the outer rotor motor is combined with the speed reducer, and the speed reducer is arranged on the periphery of the outer rotor motor, compared with the arrangement mode that the speed reducer is arranged in parallel left and right in the prior art, the concentric sleeving installation mode can effectively reduce the overall structural size of the mechanical arm joint, and has the advantages of reasonable arrangement, compact structure, small volume and the like; the output of the outer rotor motor is directly transmitted to the speed reducer assembly and is not transmitted through a rotating shaft as in the prior art, the structure is obviously simplified, the assembly is convenient, and the manufacturing cost is low; meanwhile, by adopting the trochoid speed reducing structure, the outer rotor motor is arranged inside the transmission gear, the speed ratio requirement can be met without changing the structure between the transmission gear and the gear ring, and the output of low rotating speed and high torque is realized; the application range of the mechanical arm joint is obviously enlarged, and the mechanical arm joint has better market popularization value;

2. in the invention, the eccentric mounting position is integrally formed and processed outside the motor rotor, namely the motor rotor can be used as an eccentric sleeve structure for mounting the transmission gear, the eccentric sleeve is not required to be independently fixed on the periphery of the motor rotor as in the prior art, and then the transmission gear is mounted outside the eccentric sleeve; and through simplifying the structure, also can reduce the whole volume of structure, realize the demand that compact structure, miniaturization.

Drawings

The drawings are only for purposes of illustrating and explaining the present invention and are not to be construed as limiting the scope of the present invention.

FIG. 1 is a schematic diagram of the structure of an embodiment of the present invention;

FIG. 2 is a schematic diagram of another angle configuration of an embodiment of the present invention;

FIG. 3 is a first schematic diagram illustrating a usage state of the present invention;

FIG. 4 is a second schematic diagram illustrating the usage state of the present invention;

in the figure: 1-a joint shell; 2-an outer rotor motor; 21-a motor stator; 22-a motor rotor; 3-a retarder assembly; 31-a transmission gear; 32-fixed gear ring; 33-planet carrier upper cover; 34-lower cover of planet carrier; 35-a check bolt; 36-a positioning sleeve; 37-torque transmission pin; 38-pin boss; 4-an encoder component; 41-a code-reading element; 42-code disc outer ring plate; 43-code disc inner ring plate; 5-drive controller.

Detailed Description

The invention is further illustrated below with reference to the figures and examples. In the following detailed description, certain exemplary embodiments of the present invention are described by way of illustration only. Needless to say, a person skilled in the art realizes that the described embodiments can be modified in various different ways without departing from the spirit and scope of the present invention. Accordingly, the drawings and description are illustrative in nature and not intended to limit the scope of the claims.

As shown in fig. 1 and 2, the integrated outer rotor mechanical arm joint includes a joint housing 1, the joint housing 1 is used as a mounting carrier of a mechanical arm joint, a semi-enclosed structure is adopted, an outer rotor motor 2 is mounted in the joint housing 1, the outer rotor motor 2 includes a motor stator 21 fixed on the joint housing 1, a motor rotor 22 used as a joint input is mounted outside the motor stator 21 in a matching manner, the motor rotor is used as an input end of a reducer assembly, N eccentric mounting positions with different phase angles are arranged on the periphery of the motor rotor 22, a phase angle between two adjacent eccentric mounting positions is 360 °/N, and N is greater than or equal to 2; the reducer assembly 3 is installed at the periphery of the motor rotor 22 and between the joint shells 1, the reducer assembly 3 is correspondingly installed at an eccentric installation position of the motor rotor 22, a planetary output frame serving as joint output is installed at the output end of the reducer assembly 3, an encoder assembly 4 is installed between the motor rotor 22 and the planetary output frame, the encoder assembly 4 is arranged on one side of the outer rotor motor 2 and the reducer assembly 3 and installed on the joint shells 1, and the planetary output frame is located outside the joint shells 1 and respectively arranged on two sides of the reducer assembly 3.

In the invention, the outer rotor motor 2 is combined with the speed reducer, and the speed reducer is arranged at the periphery of the outer rotor motor 2, compared with the arrangement mode of arranging the speed reducer in parallel left and right in the prior art, the concentric sleeving installation mode can effectively reduce the overall structural size of the mechanical arm joint, and has the advantages of reasonable arrangement, compact structure, small volume and the like; the output of the outer rotor motor 2 is directly transmitted to the reducer component 3, and is not transmitted through a rotating shaft as in the prior art, so that the structure is obviously simplified, the assembly is convenient, and the manufacturing cost is low; meanwhile, by adopting the trochoid speed reducing structure, the outer rotor motor 2 is arranged inside the transmission gear, the speed ratio requirement can be met without changing the structure between the transmission gear and the gear ring, and the output of low rotating speed and high torque is realized; the application range of the mechanical arm joint is obviously enlarged, and the mechanical arm joint has good market popularization value.

In the invention, the motor rotor 22 is integrally formed and processed with an eccentric mounting position, namely the motor rotor 22 can be used as an eccentric sleeve structure for mounting the transmission gear, an eccentric sleeve is not required to be independently fixed on the periphery of the motor rotor 22 as in the prior art, and then the transmission gear is mounted outside the eccentric sleeve; and through simplifying the structure, also can reduce the whole volume of structure, realize the demand that compact structure, miniaturization.

The speed reducer assembly 3 comprises transmission gears 31 which are respectively rotatably installed on the eccentric installation positions, the periphery of each transmission gear 31 is meshed with a fixed gear ring 32, and the fixed gear rings 32 are fixedly installed on the joint shell 1. The number of the eccentric mounting positions is at least two, and can be two, three, four or more, when two eccentric mounting positions are arranged, the phase angle between the two eccentric mounting positions is 180 degrees, and when three eccentric mounting positions are arranged, the phase angle between the three eccentric mounting positions is 120 degrees. In this embodiment, the eccentric mounting position is provided with an arc-shaped groove for mounting a bearing ball, the inner circumference of the transmission gear 31 is mounted on the eccentric mounting position through the bearing ball, the eccentric mounting position is used as a mounting bearing of the transmission gear 31, the outer circumference of the transmission gear 31 is meshed with the fixed gear ring 32 through meshing teeth matched with the fixed gear ring 32, and the motor rotor 22, the transmission gear 31 and the fixed gear ring 32 are matched to form a trochoid reducer gear set for transmitting the high rotating speed and the low torque of the motor rotor 22 to the planetary output frame at a certain speed ratio, so that the joint output is low rotating speed and high torque.

The planet output carrier comprises a planet carrier upper cover 33 and a planet carrier lower cover 34 which are coaxially matched and installed on the outer end faces of two sides of all the transmission gears 31, the planet carrier upper cover 33 serves as joint output and can serve as an installation flange of a next-stage mechanical arm, the planet carrier upper cover 33 is positioned on the outer side of the joint shell 1, the output torque of the planet carrier upper cover is equal to the output torque of a mechanical arm joint, and the encoder assembly 4 is connected to the planet carrier lower cover 34; an anti-loosening fixing device for installing all the transmission gears 31 is connected between the planet carrier upper cover 33 and the planet carrier lower cover 34, and a torque transmission device penetrating through each transmission gear 31 is further arranged between the planet carrier upper cover 33 and the planet carrier lower cover 34. The planet carrier upper cover 33 with be provided with support bearing one between the motor rotor 22, be provided with ring gear bearing one between planet carrier upper cover 33 and the fixed ring gear 32, planet carrier lower cover 34 with be provided with support bearing two between the motor rotor 22, planet carrier lower cover 34 with be provided with ring gear bearing two between the fixed ring gear 32.

Locking fixing device include with planet carrier upper cover 33 with planet carrier lower cover 34 thread tightening's check bolt 35, check bolt 35 by planet carrier lower cover 34 runs through all drive gear 31 threaded connection is to planet carrier upper cover 33, all drive gear 31 with be provided with position sleeve 36 between the check bolt 35, the both ends of position sleeve 36 support respectively and lean on planet carrier lower cover 34 and planet carrier upper cover 33. The positioning sleeve 36 is used for positioning the distance between the planet carrier upper cover 33 and the planet carrier lower cover 34.

The torque transmission device comprises a torque transmission pin shaft 37, the torque transmission pin shaft 37 penetrates through all the transmission gears 31, two ends of the torque transmission pin shaft 37 are respectively positioned on the upper cover 33 of the planet carrier and the lower cover 34 of the planet carrier, and a pin shaft sleeve 38 is respectively arranged between each transmission gear 31 and the torque transmission pin shaft 37. The outer peripheries of the pin bosses 38 are respectively installed on the transmission gears 31 in a tangent fit manner, and the pin bosses 38 are used for ensuring the installation accuracy between the transmission gears 31.

In the embodiment, twelve through holes are correspondingly formed on each transmission gear 31, six positioning holes I and six threaded holes are correspondingly formed on the planet carrier upper cover 33, the six positioning holes I and the six threaded holes are alternately arranged and correspond to the twelve through holes one by one respectively, the first positioning hole is a blind hole, the lower cover 34 of the planet carrier is correspondingly provided with six second positioning holes respectively corresponding to the first positioning holes and six stepped holes respectively corresponding to the threaded holes, the locking bolt 35 is connected to the corresponding threaded hole by the stepped hole through the corresponding through hole of each transmission gear 31, the moment transmission pin shaft 37 sequentially passes through the second positioning hole, each transmission gear 31 is correspondingly connected to the first positioning hole, the moment transmission pin 37 is tightly matched with the second positioning hole and the first positioning hole, and the second positioning hole is a through hole. The anti-loosening bolt 35 is a hexagon socket head cap screw.

In this embodiment, the lock bolt 35 is used to fixedly connect the two parts of the upper cover 33 and the lower cover 34 of the planet carrier, and the torque transmission is performed through the torque transmission pin 37 and the pin sleeve 38, and in the present invention, the lock bolt 35 and the torque transmission pin 37 are alternately matched, so that not only a good fixed installation effect can be achieved, but also the torque transmission precision of the speed reducer can be effectively improved.

Referring to fig. 1, the encoder assembly 4 serves as a detection element of the robot joint for detecting position information of the reducer output and the joint output.

The encoder assembly 4 comprises a code disc element and a code reading element 41, the code disc element comprises a code disc outer ring plate 42 and a code disc inner ring plate 43 which can rotate respectively, the code disc outer ring plate 42 is coaxially sleeved outside the code disc inner ring plate 43, the code disc outer ring plate 42 is fixed on the planet carrier lower cover 34 of the planet output carrier, and the code disc inner ring plate 43 is fixedly arranged on the motor rotor 22 through an inner ring plate bracket; the code reading element 41 is coaxially fixed on one side of the code disc element and corresponds to the code disc outer ring plate 42 and the code disc inner ring plate 43, and the code reading element 41 is correspondingly fixed on the joint shell 1. The code reading element 41 is provided with an outer ring plate detection portion corresponding to the code wheel outer ring plate 42 and an inner ring plate detection portion corresponding to the code wheel inner ring plate 43. The code reading element 41 is used as a mounting carrier of the detection circuit board, and the outer ring board detection part and the inner ring board detection part which are arranged on the code reading element are mutually independent and do not interfere with each other; the outer or inner ring plate detector can be a detection circuit board or a position sensor integrated in the code reading element 41, but can of course be a detection circuit board or a position sensor mounted on one side surface of the code reading element 41. The detection circuit board or the position sensor is known in the art and is not described herein.

And a driving assembly corresponding to the encoder assembly is further installed in the joint shell. The driving component is a driving controller 5 installed between the encoder component 4 and the joint housing 1, data transmission is performed between the code reading element 41 and the driving controller 5, that is, data information generated by the code reading element 41 can be transmitted to the driving controller 5, specifically, the outer ring plate detection part and the inner ring plate detection part are respectively in data connection with the driving controller 5, and are used for respectively transmitting position signals of the motor rotor 22 and the planet carrier upper cover 33 to the driving controller 5.

In the present embodiment, one code reading element 41 is adopted to correspond to the outer ring plate 42 of the code wheel and the inner ring plate 43 of the code wheel at the same time, that is, the purpose of detecting the motor output and the joint output at the same time is achieved, so as to reduce the volume of the encoder assembly 4. Furthermore, the code wheel outer ring plate 42 and the code wheel inner ring plate 43 are positioned on the same plane and are matched with the code reading element 41 to form a double-disc structure with a fixed movement, and the double-disc structure has the characteristics of compact structure, small volume and the like.

The working principle of the encoder assembly 4 is as follows:

when the mechanical arm joint normally operates, the motor rotor 22 drives the code disc outer ring plate 42 to rotate, the outer ring plate detection part can detect the absolute position of the code disc outer ring plate 42, and the rotating speed position of the code disc outer ring plate 42 is the absolute position of the output end of the outer rotor motor 2; meanwhile, the lower planet carrier cover 34 drives the inner ring plate 43 of the code disc to rotate, the inner ring plate detection part can detect the absolute position of the inner ring plate 43 of the code disc, and the rotating speed position of the inner ring plate 43 of the code disc is the absolute position of the output end of the speed reducer; when the outer ring plate detection part and the inner ring plate detection part respectively transmit the detected positions of the output end of the outer rotor motor 2 and the output end of the speed reducer to the drive controller 5 and the system controller, the drive controller 5 and the system controller can detect and store the relative positions of the output end of the outer rotor motor 2 and the output end of the speed reducer in real time, and a rotating speed error exists in the forward rotation and reverse rotation processes of a mechanical arm joint in the prior art, so that the actual positions output by the output end of the speed reducer have deviation, in order to solve the problem, the invention respectively measures the absolute positions of the output end of the outer rotor motor 2 and the output end of the speed reducer, and if the actual position output by the output end of the speed reducer is not equal to the theoretical position, the system controller controls the motor assembly to rotate forwards or reversely to adjust so that the actual position of the output end of the speed reducer is equal to the theoretical position, through the mode of measuring the absolute position of the output end of the speed reducer and the output end of the motor, the accurate position control of the whole mechanical arm joint is realized, and the output precision is ensured.

Referring to fig. 1 and 2, the robot joint of the present invention has a cylindrical shape, and fig. 3 and 4 are views illustrating a state of use of the robot joint, in which the robot joint is mounted in a housing, in accordance with a state of use of a robot in the related art. Referring to fig. 3, the base is now fixedly mounted with an output end; referring to fig. 4, the base is now fixedly mounted with two outputs.

The foregoing shows and describes the general principles, essential features, and advantages of the invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are described in the specification and illustrated only to illustrate the principle of the present invention, but that various changes and modifications may be made therein without departing from the spirit and scope of the present invention, which fall within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.