A robotic arm joint and a robotic arm

Abstract

The present invention discloses a robotic arm joint and a robotic arm, relating to the technical field of robotic arms. The robotic arm joint includes a body, an end cover and a speed reduction mechanism. An installation groove is provided on the body; the end cover is arranged at the opening of the installation groove, the end cover and the installation groove enclose an installation cavity, and the end cover is provided with a through hole; the speed reduction mechanism is arranged in the installation cavity, the output end of the speed reduction mechanism is connected to the body, and the input shaft of the speed reduction mechanism extends out of the installation cavity through the through hole. By arranging the speed reduction mechanism entirely on one robotic arm joint, this robotic arm joint avoids assembly errors and improves assembly efficiency.

Description

Technical Field

[0001] The present invention relates to the technical field of robotic arms, and in particular to a robotic arm joint and a robotic arm. Background Art

[0002] With the advancement of mechatronics technology and the vigorous development of the wave of artificial intelligence, industrial products are developing in the direction of intelligence, systematization, miniaturization, modularization and human-machine collaboration. On the automated production line, the assembly and transfer of parts are completed by robotic arms. Robotic arms have the development trend of high precision, modularization, lightweight and multi-degree of freedom. A robotic arm usually includes a plurality of robotic arm joints connected in sequence, and the robotic arm joints at the end thereof can be equipped with fixtures, cutting tools and detectors to perform various actions. The robotic arm joint is provided with a reduction mechanism connected to the drive device, and in the prior art, the reduction mechanism is divided into two adjacent robotic arm joints, and then the two are assembled. This makes it difficult to operate in the production process, and it is easy to produce errors in the assembly of the reduction mechanism, and the assembly efficiency is low.

[0003] In view of the above problems, it is necessary to develop a robotic arm joint and a robotic arm to solve the problem of easy assembly errors and low assembly efficiency caused by the sub-assembly of the speed reduction mechanism components. Summary of the invention

[0004] The object of the present invention is to provide a robot arm joint and a robot arm, in which all speed reduction mechanisms are arranged on one robot arm joint to avoid assembly errors and improve assembly efficiency.

[0005] To achieve this object, the present invention adopts the following technical solutions:

[0006] A mechanical arm joint, comprising:

[0007] A body, wherein a mounting groove is provided on the body;

[0008] An end cover, the end cover is arranged at the opening of the mounting groove, the end cover and the mounting groove form a mounting cavity, and the end cover is provided with a through hole;

[0009] A speed reduction mechanism is arranged in the installation cavity, an output end of the speed reduction mechanism is connected to the body, and an input shaft of the speed reduction mechanism extends out of the installation cavity through the through hole.

[0010] Preferably, the reduction mechanism is a harmonic reducer, which includes the input shaft, a wave generator arranged on the input shaft, a flexible wheel sleeved outside the wave generator, and a steel wheel capable of meshing with the flexible wheel, and the steel wheel is respectively fixed to the body and the end cover.

[0011] Preferably, the end cover includes a cover plate and an annular flange disposed around the edge of the cover plate. The inner surface of the flange is a first positioning surface, which abuts against the outer peripheral surface of the steel wheel, and the cover plate abuts against the end surface of the steel wheel.

[0012] Preferably, the end cover and the steel wheel are in interference fit.

[0013] Preferably, it further includes a guiding component, and the guiding component includes:

[0014] A first bearing, which is disposed on the bottom surface of the installation groove;

[0015] A second bearing, which is disposed in the through hole;

[0016] One end of the input shaft extending into the installation cavity is rotatably connected to the body through the first bearing, and the input shaft is rotatably connected to the end cover through the second bearing.

[0017] Preferably, it further includes a positioning component, and the positioning component includes:

[0018] A first bearing cover, which is disposed on one end face of the input shaft extending into the installation cavity, and the first bearing cover abuts against the inner ring of the first bearing;

[0019] A second bearing cover, which is sleeved outside the input shaft and connected to the end cover, and the second bearing is located between the second bearing cover and the end cover;

[0020] The wave generator abuts against the inner rings of the first bearing and the second bearing respectively.

[0021] Preferably, the side wall of the through hole is a second positioning surface, and the outer side wall of the outer ring of the second bearing abuts against the second positioning surface.

[0022] Preferably, a first sealing ring is disposed between the end surface of the steel wheel and the bottom surface of the installation groove, and a second sealing ring is disposed between the end cover and the steel wheel.

[0023] Preferably, an oil seal is disposed between the input shaft and the end cover.

[0024] A robotic arm includes the robotic arm joint described above.

[0025] Preferably, the robotic arm includes at least two of the robotic arm joints connected in sequence. An annular boss protrudes from the outside of the end cover, and the side wall of the boss is a third positioning surface. Among two adjacent robotic arm joints, the body in one robotic arm joint is buckled on the boss of the other robotic arm joint and abuts against the third positioning surface.

[0026] Advantages of the present invention:

[0027] The present invention provides a robotic arm joint and a robotic arm. In this robotic arm joint, a reduction mechanism is arranged in the installation groove of the body, and components inside the reduction mechanism are fixed by an end cover, enabling the entire robotic arm joint to be assembled with another robotic arm joint after the assembly is completed, avoiding the situation of assembling the reduction mechanism in different work positions and resulting in incorrect assembly of the reduction mechanism. At the same time, the robotic arm joint realizes modular assembly, greatly improving the production efficiency. Description of the Drawings

[0028] Figure 1 is a schematic structural diagram of the robotic arm provided by the present invention;

[0029] Figure 2 is a front view of the robotic arm joint provided by the present invention;

[0030] Figure 3 is the present invention Figure 2 a cross-sectional view taken along line A-A in;

[0031] Figure 4 is a schematic structural diagram of the body and the reduction mechanism provided by the present invention;

[0032] Figure 5 is a cross-sectional view of the end cover provided by the present invention.

[0033] 1. Body; 2. End cover; 3. Reduction mechanism; 4. Guide assembly; 5. Positioning assembly; 6. Bushing; 7. Oil seal; 8. Robotic arm;

[0034] 21. Through hole; 22. First positioning surface; 23. Second sealing ring; 24. Second positioning surface; 25. Third positioning surface; 31. Steel wheel; 32. Wave generator; 33. Input shaft; 41. First bearing; 42. Second bearing; 51. First bearing cover; 52. Second bearing cover; 81. Base; 82. First robotic arm joint; 83. Second robotic arm joint; 84. Third robotic arm joint; 85. Fourth robotic arm joint. Detailed Embodiments

[0035] The embodiments of the present invention will be described in detail below. The examples of the embodiments are shown in the drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the drawings are exemplary and are intended to explain the present invention and should not be construed as limiting the present invention.

[0036] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance. Among them, the terms "first position" and "second position" are two different positions.

[0037] Unless otherwise clearly defined and limited, the terms "installed", "connected", "connected", "fixed" shall be understood in a broad sense. For example, it can be a fixed connection or a detachable connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium. It can be the communication inside two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0038] Unless otherwise clearly defined and limited, the first feature being "above" or "below" the second feature may include the first feature and the second feature being in direct contact, or may include the first feature and the second feature not being in direct contact but being in contact through additional features therebetween. Moreover, the first feature being "above", "above", and "on" the second feature includes the first feature being directly above and obliquely above the second feature, or merely indicating that the first feature is at a higher horizontal height than the second feature. The first feature being "below", "below", and "under" the second feature includes the first feature being directly below and obliquely below the second feature, or merely indicating that the first feature is at a lower horizontal height than the second feature.

[0039] The technical solution of the present invention will be further described below with reference to the drawings and through specific embodiments.

[0040] As Figure 1 shown, this embodiment provides a robotic arm 8, which includes a plurality of robotic arm joints connected in sequence. The end of the robotic arm 8 is used to connect the actuator, and two adjacent robotic arm joints are drivingly connected to achieve multi-degree-of-freedom movement of the end of the robotic arm 8.

[0041] Specifically, the robot 8 includes a base 81, a first robot joint 82, a second robot joint 83, a third robot joint 84 and a fourth robot joint 85. The first robot joint 82 on the base 81 can rotate around the Z axis, the first robot joint 82 can drive the second robot joint 83 to rotate around the X axis, the second robot joint 83 can drive the third robot joint 84 to rotate around the X axis, and the third robot joint 84 can drive the fourth robot joint 85 to rotate around the Z axis.

[0042] Among two adjacent robot arm joints, the driven robot arm joint is transmission-connected to the output end of the other adjacent robot arm joint through the input shaft 33 of the reduction mechanism 3, and the reduction mechanism 3 may be a harmonic reducer or a planetary gear reducer.

[0043] Since the harmonic reducer has the advantages of high reduction ratio and high precision, it can improve the rotation accuracy of the robot arm joint. The harmonic reducer can achieve a very high reduction ratio in a smaller volume and can greatly reduce the space occupied by the robot arm joint. Therefore, a harmonic reducer is used in the robot arm joint in this embodiment.

[0044] To facilitate the assembly of the robot arm 8, in this embodiment, the speed reduction mechanism 3 is integrated into the driven robot arm joint, so that each robot arm joint has a high degree of modularity. After the robot arm joint is assembled, two adjacent robot arm joints can be assembled to solve the problem of easy assembly errors and low assembly efficiency caused by the components of the speed reduction mechanism 3 being separately assembled in two robot arm joints. In this embodiment, the third robot arm joint 84 is taken as an example for introduction.

[0045] like Figure 2 and Figure 3 As shown, the mechanical arm joint includes a body 1, an end cover 2 and a speed reduction mechanism 3. The body 1 is provided with a mounting groove, the end cover 2 is arranged at the opening of the mounting groove and is relatively fixed to the body 1, the end cover 2 and the mounting groove form a mounting cavity, the end cover 2 is provided with a through hole 21, the speed reduction mechanism 3 is arranged in the mounting cavity, the output end of the speed reduction mechanism 3 is connected to the body 1, and the input shaft 33 of the speed reduction mechanism 3 extends out of the mounting cavity through the through hole 21.

[0046] The mechanical arm 8 installs all the components of the reduction mechanism 3 on the third mechanical arm joint 84 through the end cover 2. This makes it unnecessary to first split the reduction mechanism 3, install them in the two mechanical arm joints respectively, and then assemble the two when assembling the third mechanical arm joint 84 and the second mechanical arm joint 83. Instead, the reduction mechanism 3 can be completely assembled on the third mechanical arm joint 84, and then the second mechanical arm joint 83 can be assembled on the input shaft 33 as a whole. The advantage of this is that only the structures that match each other on the two mechanical arm joints need to be assembled, and then the driving member is connected to the input shaft 33 of the reduction mechanism 3 by transmission. Compared with connecting the two mechanical arm joints through the components of the reduction mechanism 3, such modular assembly greatly reduces the occurrence of assembly errors and improves production efficiency. Moreover, since the mechanical arm joints are heavy, the more complex the assembly structure is, the more difficult it is to grasp the assembly accuracy, resulting in low accuracy of the mechanical arm 8 and inability to perform refined work. The mechanical arm 8 is more convenient for replacing and maintaining the reduction mechanism 3.

[0047] By providing the end cover 2, the modularity of the third robot arm joint 84 can be improved, and the two robot arm joints that cooperate with each other can be assembled separately and then assembled, which is conducive to the reasonable division of the assembly production line, thereby improving the assembly efficiency.

[0048] In addition, the modular design of the robot arm joints can facilitate the standardized production of the robot arm joints, so that the structure of the joints can be used for the connection of a variety of robot arms, greatly improving the applicability of the parts, enabling large-scale production and reducing production costs.

[0049] Preferably, the speed reduction mechanism 3 is a harmonic speed reducer, including an input shaft 33, a wave generator 32 arranged on the input shaft 33, a flexible wheel sleeved outside the wave generator 32, and a steel wheel 31 that can mesh with the flexible wheel, and the steel wheel 31 is fixed to the body 1 and the end cover 2 respectively. When the input shaft 33 rotates, the wave generator 32 is driven to rotate to generate a periodic elastic deformation wave to deform the flexible wheel. The elongated part of the flexible wheel meshes with the inner ring of the steel wheel 31, and the remaining part is disengaged from the steel wheel 31. The tooth pitch of the flexible wheel and the steel wheel 31 is equal, but the number of teeth is small, so that the flexible wheel and the steel wheel 31 rotate relative to each other. When one of them is fixed, the other outputs torque and speed as an output end. In this embodiment, the steel wheel 31 is fixedly connected to the body 1 of the third mechanical arm joint 84 as a fixing member, and the rotation of the mechanical arm joint is realized by the rotation of the steel wheel 31.

[0050] It should be noted that the harmonic reducer can adopt any structure in the art, and the specific structure of the harmonic reducer and the connection relationship between the various components will not be specifically introduced in this embodiment.

[0051] It is understandable that the end cover 2 may also be directly fixedly connected to the body 1 .

[0052] Preferably, the end cap 2 includes a cover plate and a circular flange disposed around the edge of the cover plate. The inner surface of the flange is the first positioning surface 22, which abuts against the outer peripheral surface of the steel wheel 31, and the cover plate abuts against the end surface of the steel wheel 31. Through the cooperation between the first positioning surface 22 and the outer peripheral surface of the steel wheel 31, the accuracy of the third robotic arm joint 84 can be improved, making the input shaft 33 rotate more smoothly, and the difficulty of assembling the end cap 2 is reduced, greatly improving the work efficiency.

[0053] Preferably, the end cap 2 and the steel wheel 31 are in interference fit, which can eliminate the assembly gap between the end cap 2 and the steel wheel 31. During the operation of the reduction mechanism 3, the end cap 2 will not become loose due to the vibration caused by the high-speed rotation of the input shaft 33, thereby improving the trajectory operation accuracy of the robotic arm 8 and reducing the noise at the same time. The reduction of the operating noise of the transmission system can improve the competitiveness of the robotic arm 8 product.

[0054] Furthermore, the steel wheel 31 includes a large-diameter section and a small-diameter section. The large-diameter section is close to the inner side of the body 1, and the small-diameter section is in interference fit with the end cap 2. The steel wheel 31 can be fixedly connected to the body 1 by bolts. The bolts are screwed in from the step surface formed at the connection between the large-diameter section and the small-diameter section and are threadedly connected to the body 1.

[0055] Preferably, the third robotic arm joint 84 further includes a guiding component 4, which includes a first bearing 41 and a second bearing 42. The first bearing 41 is disposed on the bottom surface of the installation groove, and the second bearing 42 is disposed in the through hole 21. One end of the input shaft 33 extending into the installation cavity is rotatably connected to the body 1 through the first bearing 41, and the input shaft 33 is rotatably connected to the end cap 2 through the second bearing 42. The bearings are used to reduce the friction suffered by the input shaft 33 during rotation, reduce the loss during transmission, and improve the transmission efficiency.

[0056] Preferably, the third robotic arm joint 84 further includes a positioning component 5, which includes a first bearing cover 51 and a second bearing cover 52. The first bearing cover 51 is disposed on one end face of the input shaft 33 extending into the installation cavity. The first bearing cover 51 abuts against the inner ring of the first bearing 41. The second bearing cover 52 is sleeved outside the input shaft 33 and is connected to the end cap 2. The second bearing 42 is located between the second bearing cover 52 and the end cap 2. The wave generator 32 abuts against the inner rings of the first bearing 41 and the second bearing 42 respectively.

[0057] The second bearing cover 52 and the end cap 2 jointly fix the second bearing 42, and the wave generator 32 abuts against the inner rings of the first bearing 41 and the second bearing 42. The three jointly rotate with the input shaft 33, and the axial positioning of the entire structure is achieved through the first bearing cover 51.

[0058] In other embodiments, the third robotic arm joint 84 further includes a bushing 6, which is disposed between the first gear and the wave generator 32, and between the second gear and the wave generator 32. The bushing 6 abuts against the inner ring of the first gear, the wave generator 32, and the inner ring of the second gear, and rotates synchronously with the input shaft 33, and all components are stably fixed.

[0059] To prevent relative sliding between the input shaft 33 and the wave generator 32, which may lead to a reduction in transmission efficiency, in this embodiment, a flat key is provided on the input shaft 33. A part of the flat key is embedded in the input shaft 33, and the other part is embedded in the wave generator 32, ensuring their synchronous rotation.

[0060] Wherein, a first sealing ring is provided between the end face of the steel wheel 31 and the bottom surface of the mounting groove, and a second sealing ring 23 is provided between the end cover 2 and the steel wheel 31. The space jointly enclosed by the end cover 2, the steel wheel 31, and the body 1 is divided into two oil cavities by the wave generator 32, and both oil cavities are filled with lubricating grease for lubricating the first bearing 41 and the second bearing 42 to reduce wear.

[0061] In this embodiment, by providing the end cover 2, modular design of the third robotic arm joint 84 is achieved, which can ensure that when the third robotic arm joint 84 is disassembled from another robotic arm it is mating with, the oil cavity inside the third robotic arm joint 84 always remains sealed, preventing leakage of lubricating grease.

[0062] Further, in order to prevent grease leakage when disassembling and maintaining the two robotic arm joints, an oil seal 7 is provided between the input shaft 33 and the end cover 2.

[0063] Preferably, the side wall of the through hole 21 of the end cover 2 is a second positioning surface 24, and the outer side wall of the outer ring of the second bearing 42 abuts against the second positioning surface 24. The second positioning surface 24 provides accuracy guarantee for the position of the second bearing 42 and the oil seal 7, reducing the wobbling of the input shaft 33 during rotation and improving accuracy. Among them, the second positioning surface 24 can be provided in two stepped sections for abutting against the outer rings of the second bearing 42 and the oil seal 7 respectively.

[0064] Preferably, an annular boss is convexly provided on the outer side of the end cover 2, and the side wall of the boss is a third positioning surface 25. In two adjacent robotic arm joints, the body 1 of the second robotic arm joint 83 is buckled on the boss of the third robotic arm joint 84 and abuts against the third positioning surface 25. The third positioning surface 25 can reduce the difficulty for operators to assemble the robotic arm 8, provide a reference for the operators' assembly, greatly improve the assembly efficiency, and ensure the assembly accuracy.

[0065] During the assembly process of the robotic arm joint, the assembly steps are as follows:

[0066] S1: Mount the steel gear 31 of the harmonic reducer on the body 1 of the third robotic arm joint 84 by screws;

[0067] S2: Pass the input shaft 33 through the second bearing 42, and install the second bearing 42 into the through hole 21 of the end cover 2, so that the outer surface of the second bearing 42 abuts against the second positioning surface 24;

[0068] S3: Use screws to install the second bearing cover 52 on the end cover 2 to fix the outer ring of the second bearing 42;

[0069] S4: Install the wave generator 32 and the first bearing 41 on the input shaft 33 in sequence, and install a bushing 6 between the second bearing 42 and the wave generator 32 and between the wave generator 32 and the first bearing 41 respectively;

[0070] S5: Install the first bearing cover 51 on the input shaft 33 at one end of the first bearing 41 by screws, and make the first bearing 41, the wave generator 32, the second bearing 42 and the two bushings 6 abut tightly in the axial direction of the input shaft 33;

[0071] S6: Snap the end cover 2 onto the steel gear 31 and fix it with screws, and at the same time fix the first bearing 41 on the bottom surface of the body 1;

[0072] S7: Install a oil seal 7 between the input shaft 33 and the second positioning surface 24 of the end cover 2.

[0073] During the assembly process of the third robotic arm joint 84, except for the steel gear 31, other structures of the reduction mechanism 3 are assembled with the end cover 2 and then installed into the body 1, which is convenient for installation, disassembly and maintenance.

[0074] In some embodiments, the steel gear 31 can also be first installed on the end cover 2 together with other structures in the reduction mechanism 3, and then the end cover 2 and the reduction mechanism 3 are installed in the body 1. Since the stepped surface of the steel gear 31 is exposed outside the end cover 2, bolts can be screwed in from the stepped surface to fix the steel gear 31 and the body 1 with screws.

[0075] It can be understood that the robotic arm 8 has relatively high requirements for the rotation accuracy of the input shaft 33. During the assembly process, the first positioning surface 22, the second positioning surface 24 and the third positioning surface 25 on the end cover 2 can well guarantee the accuracy and reduce the assembly difficulty. And the three positioning surfaces of the end cover 2 are all circumferential surfaces and are coaxially arranged. They can be machined by a lathe, with simple operation and it is easier to ensure the coaxial accuracy of the three surfaces, providing guarantee for the high precision of subsequent assembly. Moreover, the coaxiality here will help to reduce the vibration and noise caused by the high-speed movement of the shafting during the operation of the robotic arm 8. Reducing the vibration of the transmission system can reduce the jitter of the robot end, thereby improving the trajectory operation accuracy of the robot. Reducing the running noise of the transmission system can improve the competitiveness of the robot product.

[0076] Preferably, the second robotic arm joint 83 is further provided with a rotary motor, and the output shaft of the rotary motor can drive the input shaft 33 to rotate. By using the rotary motor to drive the input shaft 33 to rotate and reducing the rotational speed through the speed reduction mechanism 3, the third robotic arm joint 84 can be driven to rotate relative to the second robotic arm joint 83, and the relative rotation angle of the two robotic arm joints can be calculated based on the rotational speed of the rotary motor and the speed reduction ratio of the speed reduction mechanism 3.

[0077] Preferably, the rotary motor can drive the input shaft 33 to rotate through a gear set, or can also drive the input shaft 33 by tensioning a belt on the output shaft and the input shaft 33.

[0078] The above content is only a preferred embodiment of the present invention. For those of ordinary skill in the art, according to the idea of the present invention, there will be changes in the specific implementation manner and application scope. The content of this specification should not be construed as a limitation to the present invention.

Claims

1. A robotic arm, characterized in that, The robotic arm includes a plurality of robotic arm joints, and the robotic arm joints include: A body (1) with a mounting groove provided thereon; An end cap (2) disposed at the opening of the mounting groove. The end cap (2) and the mounting groove enclose a mounting cavity, and the end cap (2) is provided with a through hole (21); A reduction mechanism (3) disposed in the mounting cavity. The output end of the reduction mechanism (3) is connected to the body (1), and the input shaft (33) of the reduction mechanism (3) extends out of the mounting cavity through the through hole (21); When assembling the robotic arm, the reduction mechanism (3) is fully assembled on one of the robotic arm joints, and then the other robotic arm joint is integrally assembled on the input shaft (33); The reduction mechanism (3) is a harmonic reducer, which includes the input shaft (33), a wave generator (32) disposed on the input shaft (33), a flexible gear sleeved outside the wave generator (32), and a steel gear (31) capable of meshing with the flexible gear. The steel gear (31) is fixed to the body (1) and the end cap (2) respectively; It further includes a guiding component (4), and the guiding component (4) includes: A first bearing (41) disposed on the bottom surface of the mounting groove; A second bearing (42) disposed in the through hole (21); One end of the input shaft (33) extending into the mounting cavity is rotatably connected to the body (1) through the first bearing (41), and the input shaft (33) is rotatably connected to the end cap (2) through the second bearing (42).

2. The robotic arm according to claim 1, wherein The end cap (2) includes a cover plate and a circular flange disposed around the edge of the cover plate. The inner surface of the flange is a first positioning surface (22), and the first positioning surface (22) abuts against the outer peripheral surface of the steel gear (31). The cover plate abuts against the end face of the steel gear (31).

3. The robotic arm according to claim 2, characterized in that, The end cap (2) and the steel gear (31) are in interference fit.

4. The robotic arm according to claim 1, wherein, It further includes a positioning component (5), and the positioning component (5) includes: A first bearing cover (51) disposed on one end face of the input shaft (33) extending into the mounting cavity. The first bearing cover (51) abuts against the inner ring of the first bearing (41); A second bearing cover (52) sleeved outside the input shaft (33) and connected to the end cap (2). The second bearing (42) is located between the second bearing cover (52) and the end cap (2); The wave generator (32) abuts against the inner rings of the first bearing (41) and the second bearing (42) respectively.

5. The robotic arm according to claim 1, characterized in that, The side wall of the through hole (21) is a second positioning surface (24), and the outer side wall of the outer ring of the second bearing (42) abuts against the second positioning surface (24).

6. The robotic arm according to claim 1, characterized in that, A first sealing ring is disposed between the end face of the steel gear (31) and the bottom surface of the mounting groove, and a second sealing ring (23) is disposed between the end cap (2) and the steel gear (31).

7. The robotic arm according to claim 1, characterized in that, An oil seal (7) is provided between the input shaft (33) and the end cover (2).

8. The robotic arm according to claim 1, wherein, The robotic arm includes at least two robotic arm joints connected in sequence. An annular boss protrudes from the outer side of the end cover (2), and the side wall of the boss is a third positioning surface (25). Among two adjacent robotic arm joints, the body (1) in one robotic arm joint is buckled on the boss of the other robotic arm joint and abuts against the third positioning surface (25).

Images