Robotic joint
Patent Information
- Application Number
- PCT/CN2025/079043
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2025-02-25
- Publication Date
- 2026-09-03
Smart Images

Figure CN2025079043_03092026_PF_FP_ABST
Abstract
Description
ROBOTIC JOINTFIELD
[0001] Embodiments of the present disclosure generally relate to a robot, and more specifically, to a robotic joint with improved sealing performances.BACKGROUND
[0002] Multi-axis industrial robots are widely used in various fields. A robot typically comprises a manipulator formed by a plurality of joints. Each joint comprises a fixed part and a movable part rotatable with respect to the fixed part. A tool may be fixed to an end flange of the manipulator. During operation of the robot, the manipulator and hence the tool is designed to move within a working space of the robot such that various tasks can be automatically performed.
[0003] In many applications, such as hygienic applications including food, beverage, dairy, pharmaceutical, medical industries and the like, chemicals are widely used. Robots used in these industries should be able to withstand these chemicals. At an interface between one component of a robotic joint and the other component of the robotic joint, a sealing device is provided to prevent the chemicals from entering an inner side of the robotic joint. The conventional sealing device, however, is not satisfactory in terms of structural complexity, the sealing performances and costs. There is a need to improve the robotic joint.SUMMARY
[0004] Example embodiments of the present disclosure provide a robotic joint which can improve sealing performances at an interface between the fixed part and the movable part of the robotic joint.
[0005] In a first aspect of the present disclosure, there is provided a robotic joint. The robotic joint comprises: a first robotic casing comprising an inner chamber; and a second robotic casing configured to rotate with respect to the first robotic casing around an axial direction; wherein the robotic joint further comprises a sealing apparatus arranged between the first robotic casing and the second robotic casing, the sealing apparatus comprising: a sleeve made of a plastic material, the sleeve comprising an axial hole and a sealing surface; and a sealing ring made of a flexible material, the sealing ring comprising a mounting portion and a sealing lip protruding from the mounting portion, the sealing lip being configured to abut against the sealing surface to form a sealing interface. By provision of the sleeve made of a plastic material, direct contact between the first and second casings can be prevented with a simplified design.
[0006] In some embodiments, the robotic joint may further comprise a drive unit configured to drive the second robotic casing to rotate with respect to the first robotic casing around the axial direction, wherein the drive unit comprises a fixed part, fixed to the first robotic casing, arranged in the chamber, and a movable part fixed to the second robotic casing; wherein the sleeve is provided on one of the first robotic casing and the second robotic casing and / or on one of the fixed part and the movable part of the drive unit, and the sealing ring is provided on the other of the first robotic casing and the second robotic casing and / or on the other of the fixed part and the movable part of the drive unit. By provision of the sleeve, direct contact between the first robotic casing and the second robotic casing is prevented.
[0007] In some embodiments, the sleeve may comprise a tubular body extending in the axial direction and defining the sealing surface, the sealing surface extending along the axial direction.
[0008] In some embodiments, the sleeve may be formed as an annular plate and comprises an annular plate body extending in a radial direction perpendicular to the axial direction and defining the sealing surface, the sealing surface extending along the radial direction.
[0009] In some embodiments, the plastic material may be selected from a group comprising of Polytetrafluoroethylene (PTFE) , Polyphenylene sulfide (PPS) preferably with glass fibers, a plastic material for producing a plastic bearing.
[0010] In some embodiments, the sleeve may be integrally formed with the one of the first robotic casing and the second robotic casing via injection molding.
[0011] In some embodiments, the sleeve may comprise a first sleeve mounting flange extending inwardly in a radial direction perpendicular to the axial direction around the axial hole from the tubular body, and the first sleeve mounting flange is configured to attach the sleeve to the one of the fixed part and the movable part of the drive unit.
[0012] In some embodiments, the sealing lip of the sealing ring may at least partially extend along the axial direction and is elastically biased onto the sealing surface.
[0013] In some embodiments, the sleeve may further comprise a second sleeve mounting flange extending outwardly in the radial direction, and when the sleeve is fixed to the one of the fixed part and the movable part of the drive unit, the second sleeve mounting flange abuts against an axial end surface of the respective robotic casing of the first and the second robotic casings.
[0014] In some embodiments, the sleeve may comprise a sleeve mounting flange extending, from the annular plate body, inwardly in the radial direction perpendicular to the axial direction around the axial hole, and the sleeve is mounted to the one of the fixed part and the movable part of the drive unit via the sleeve mounting flange.
[0015] In some embodiments, the sealing lip of the sealing ring may at least partially extend along the radial direction and is elastically biased onto the sealing surface.
[0016] In some embodiments, the mounting portion is elastically compressed in a groove formed by the other of the first robotic casing and the second robotic casing and / or by the other of the fixed part and the movable part of the drive unit.
[0017] In some embodiments, the mounting portion may be held by the other of the first robotic casing and the second robotic casing and / or by the other of the fixed part and the movable part of the drive unit via a shape fit.
[0018] In a second aspect of the present disclosure, there is provided a robot. The robot comprises a manipulator, the manipulator comprising at least one robotic joint according to any of the first aspect.
[0019] It would be appreciated that this summary is not intended to identify key features or essential features of embodiments of the present disclosure, nor is it intended to be used to limit the scope of the present disclosure. Other features of the present disclosure will become evident through the following description.BRIEF DESCRIPTION OF THE DRAWINGS
[0020] Through the following detailed descriptions with reference to the accompanying drawings, the above and other objectives, features and advantages of the example embodiments disclosed herein will become more comprehensible. In the drawings, several example embodiments disclosed herein will be illustrated in an example and in a non-limiting manner, wherein:
[0021] Fig. 1 is an overall perspective view of a robot according to an example embodiment of the present disclosure;
[0022] Fig. 2 is a plane view of a robotic joint according to a first example embodiment of the present disclosure;
[0023] Fig. 3 is a sectional view of the robotic joint shown in Fig. 2 cut along its axial direction;
[0024] Fig. 4 is a perspective view of a first robotic casing as well as the drive unit of the robotic joint shown in Fig. 2;
[0025] Fig. 5 is a sectional view of the first robotic casing as well as the drive unit shown in Fig. 4 cut along its axial direction;
[0026] Fig. 6 is an exploded view of the first robotic casing as well as the drive unit shown in Fig. 4;
[0027] Fig. 7 is a plane view of a robotic joint according to a second example embodiment of the present disclosure;
[0028] Fig. 8 is a sectional view of the robotic joint shown in Fig. 7 cut along its axial direction;
[0029] Fig. 9 is a perspective view of a first robotic casing as well as the drive unit of the robotic joint shown in Fig. 7;
[0030] Fig. 10 is a sectional view of the first robotic casing as well as the drive unit shown in Fig. 9 cut along its axial direction; and
[0031] Fig. 11 is an exploded view of the first robotic casing as well as the drive unit shown in Fig. 9.
[0032] Throughout the drawings, the same or similar reference symbols are used to indicate the same or similar elements.DETAILED DESCRIPTION OF EMBODIMENTS
[0033] Principles of the present disclosure will now be described with reference to several example embodiments shown in the drawings. Though example embodiments of the present disclosure are illustrated in the drawings, it is to be understood that the embodiments are described only to facilitate those skilled in the art in better understanding and thereby achieving the present disclosure, rather than to limit the scope of the disclosure in any manner.
[0034] The term “comprises” or “includes” and its variants are to be read as open terms that mean “includes, but is not limited to. ” The term “or” is to be read as “and / or” unless the context clearly indicates otherwise. The term “based on” is to be read as “based at least in part on. ” The term “being operable to” is to mean a function, an action, a motion or a state that can be achieved by an operation induced by a user or an external mechanism. The term “one embodiment” and “an embodiment” are to be read as “at least one embodiment. ” The term “another embodiment” is to be read as “at least one other embodiment. ” The terms “first, ” “second, ” and the like may refer to different or same objects. Other definitions, explicit and implicit, may be included below. A definition of a term is consistent throughout the description unless the context clearly indicates otherwise.
[0035] Fig. 1 is an overall view of a robot 1 according to one example embodiment of the present disclosure. As shown in Fig. 1, the robot 1 comprises a manipulator. The manipulator 1 includes a plurality of joints. The manipulator may comprise a plurality of robotic casings 10a, 10b, 10c, 10d, 10e, 10f. An end flange 10g is provided on the robotic casing 10f and a tool (not shown) may be fixed to the end flange 10g. Two adjacent robotic casings form one robotic joint. One robotic casing is configured to rotate with respect to the other adjacent robotic casing. In the shown embodiment, the manipulator 1 is a six-axis manipulator and comprises six robotic joints. It is to be understood that the number of the axes may be any other proper number, for example, 4, 5, 7, and more.
[0036] Figs. 2-6 show a robotic joint comprising a sealing apparatus according to a first example embodiment of the present disclosure. Fig. 2 is its outer appearance view of the robotic joint and Fig. 3 shows its inner components. Fig. 4 shows a perspective view of a first robotic casing of the robotic joint as well as the drive unit; Fig. 5 is a sectional view of Fig. 4 cut along its axial direction; and Fig. 6 is an exploded view of the first robotic casing shown in Fig. 4.
[0037] As shown in Figs. 2 and 3, the robotic joint comprises a first robotic casing 10 and a second robotic casing 20. The first robotic casing 10 comprises a first chamber 11. In the shown example, the first robotic casing 10 is of a shape of a bent tube. It is to be understood that the first robotic casing 10 may be of any other proper shape. The second robotic casing 20 comprises a second chamber 21. In the shown example, the second robotic casing 20 is of a shape of a bent tube. It is to be understood that the second robotic casing 20 may be of any other proper shape. The second robotic casing 20 is arranged adjacent to one axial end of the first robotic casing 10 and is driven by a drive unit 30 mounted on the first robotic casing 10. At the opposite end of the first robotic casing 10, a link or another robotic joint may be provided.
[0038] As shown in Figs. 3-6, a drive unit 30 may be provided in the inner chamber 11 of the first robotic casing 10 of the robotic joint. The drive unit 30 is configured to drive the second robotic casing 20 to rotate with respect to the first robotic casing 10 around an axial direction X1. The drive unit 30 may comprise a fixed part 32 and a movable part 34 coupled to the fixed part 32. The fixed part 32 may be fixed to the first robotic casing 10 and is received in the first chamber 11. The movable part 34 is fixed to the second robotic casing 20. When a motor of the drive unit 30 operates, the movable part 34 and thus the second robotic casing 20 rotates with respect to the first robotic casing 10 accordingly. As shown in Fig. 3, another drive unit 30 may be provided in the inner chamber of the second robotic casing 20 of the robotic joint. The drive unit 30 in the second robotic casing 20 is configured to drive a robotic casing (not shown) of an adjacent robotic joint around an axial direction X2.
[0039] In some embodiments, as shown in Figs. 3-6, the drive unit 30 may be an actuator including a motor 33 and a gearbox 35. A stator of the motor 33 is fixed to the first robotic casing 10. In some embodiments (not shown) , in addition to the motor 33 and the gearbox 35, the drive unit 30 may further include a transmission device, such as a belt-transmission, a gear-transmission and the like, between the motor and the gearbox. The gearbox 35 may include an input portion fixed to a rotor of the motor and an output portion fixed to the second robotic casing 20. According to the present disclosure, the term “fixed part” refers to the stationary components in the drive unit 30, including the stator of the motor, the fixed component in the gearbox, and the like. Likewise, the term “movable part” refers to the rotatory components in the drive unit 30, including the rotor of the motor, the rotatory component in the gearbox (for example, the input portion, the output portion) , and the like.
[0040] As shown in Figs. 2-5, the fixed part 32 and the movable part 34 are shaped to define an axial recess 40 therebetween. A sealing apparatus 50 is arranged in the axial recess 40. By provision of the axial recess 40, the sealing apparatus 50 can prevent foreign matters from entering an inner portion of the robotic joint through a clearance between the first robotic casing 10 and the second robotic casing 20.
[0041] In some embodiments, the movable part 34 includes a first flange 37 for coupling to the second robotic casing 20. The first flange 37 may include a plurality of screw holes 372. The movable part 34 may be fixed to the second robotic casing 20 via screw fasteners. The fixed part 32 adjacent to the first flange 37 may include a second flange 39. In some embodiments, as best shown in Figs. 3, 5, and 6, the second flange 39 is a stationary portion of the gearbox 35. The axial recess 40 has a smaller diameter than an outer size of the first flange 37 of the movable part 34 and an outer size of the second flange 39 of the gearbox 35.
[0042] In many applications, such as food, beverage, dairy, pharmaceutical, medical industries and the like, robots are made of material that can withstand chemicals. Corrosive -resistant materials, such as a stainless steel, may be used for producing the robotic casings 10, 20. At the interfaces of the robotic casings 10, 20, there is a need to prevent the two adjacent robotic casings 10, 20 from contacting. This imposes requirements on the structure of the sealing apparatus 50. The reason is below. After long term use, corrosion may occur at the interface if there is direct metal to metal contact at the interface. Thus, there is a need to provide a sealing apparatus 50 that prevents two adjacent robotic casings 10, 20 from contacting.
[0043] In some embodiments, as shown in Figs. 3-6, the sealing apparatus 50 comprises a sleeve 54 and a sealing ring 52. The sleeve 54 may be made of a rigid material, for example, a non-metal material, such as a plastic material. The sealing ring 52 may be made of flexible material. The sleeve 54 comprises an axial hole 542 for passage of a transmission shaft 31 of the drive unit, and a sealing surface 544. The sealing ring 52 may comprise a mounting portion 524 and a sealing lip 522 protruding from the mounting portion 524. The sealing lip 522 is configured to abut against the sealing surface 544 to form a sealing interface.
[0044] In some embodiments, the sleeve 54 may be provided on one of the fixed part 32 and the movable part 34. In addition, or alternatively, the sleeve 54 may be provided on one of the first robotic casing 10 and the second robotic casing 20. The sleeve 54 may be provided on the other of the fixed part 32 and the movable part 34. In addition, or alternatively, the sleeve 54 may be provided on the first robotic casing 10 and the second robotic casing 20.
[0045] In some embodiments, as shown in Figs. 3-6, the sleeve 54 may be provided on the movable part 34. The sleeve 54 is provided on the first robotic casing 10 and / or the fixed part 32. It is be understood that the shown example is merely illustrative. In some unshown embodiments, the sleeve 54 may be provided on the fixed part 32 and the sleeve 54 may be provided on the second robotic casing 20 and / or the movable part 34.
[0046] As shown in Figs. 3-6, the sleeve 54 may comprise a tubular body 546 extending in the axial direction and defining the sealing surface 544. The sealing surface 544 extends along the axial direction. The sealing lip 522 at least axially protrudes from the mounting portion 524. The sealing lip 522 is configured to axially abut against the sealing surface 544 to form an air-tight sealing interface. The sleeve 54 may further comprise a first sleeve mounting flange 548 configured to attach the sleeve 54 to the second robotic casing 20. The first sleeve mounting flange 548 may extend inwardly in a radial direction perpendicular to the axial direction around the axial hole 542 from the tubular body 546. The first sleeve mounting flange 548 may comprise a plurality of mounting holes 549 for passage of screw fasteners 55. Screw fasteners 55 are used for attaching the sleeve 54 to the fixed part 32 of the drive unit 30.
[0047] In some embodiments, the sleeve 54 may further comprise a second sleeve mounting flange 545 extending outwardly in the radial direction. When the sleeve 54 is fixed to the movable part 34, the second sleeve mounting flange 545 abuts against an axial end surface of the second robotic casing 20. The second sleeve mounting flange 545 forms a part of an outer surface of the robotic joint.
[0048] There are a plurality of means for mounting the sealing ring 52. In some embodiments, as shown in Figs. 3-6 (as best shown in Figs. 3 and 5) , a groove 25 may be formed on an outer circumferential surface of the robotic joint. The mounting portion 524 is elastically compressed in the groove 25. In some embodiments, the groove 25 is defined by a part of the first robotic casing 10 and a part of the fixed part 32. Thus, the mounting portion 524 of the sealing ring 52 is sandwiched between the first robotic casing 10 and the fixed part 32. In some embodiments, the groove 25 is defined merely by the first robotic casing 10. Thus, the mounting portion 524 of the sealing ring 52 is received in the groove in the first robotic casing 10. In some embodiments, the mounting portion 524 is held by the first robotic casing 10and / or by the fixed part 32 via a shape fit.
[0049] In some embodiments, the sleeve 54 may be integrally formed with the one of the first robotic casing 10 and the second robotic casing 20 via injection molding.
[0050] According to the present disclosure, by provision of the sleeve 54 at the sealing interface, the risk that the two adjacent robotic casings 10, 20 contact with each other is obviated. In some embodiments, the two adjacent robotic casings 10, 20 may be made of metal material, such as a stainless steel and the sleeve 54 may be made of a non-metal material, such as a plastic material. Thus, the metal to metal interface in the robotic joint is obviated.
[0051] In some embodiments, the plastic material needs to meet at least one of the following characteristics: -Resistant to chemical detergents, e.g. hydrogen peroxide; -Resistant to wearing and low friction, to prevent large friction torque and wear; -Ease of machining, which can achieve good dimensional tolerance and surface roughness, -Compliance with FDA requirements, and permission to use in the food industry.
[0052] In some embodiments, the plastic material may be Polytetrafluoroethylene PTFE. It has good self-lubricating properties. In some embodiment, the plastic material may be Polyphenylene sulfide PPS, preferably with glass fibers, for example, with 40%glass fibers. It has good abrasion resistance and hardness, can be used in the food and drinking water industry. In some embodiments, the plastic material may be a plastic material for producing a plastic bearing, for example, a plastic material from Igus. It has good abrasion resistance and is an FDA-compliant material.
[0053] Figs. 7-11 show a robotic joint according to a second example embodiment of the present disclosure. The embodiment shown in Figs. 7-11 is analogous to that shown in Figs. 2-6. Emphasis is placed on their differences. As shown in Figs. 7-11, the robotic joint comprises a first robotic casing 10 and a second robotic casing 20. The first robotic casing 10 comprises a first chamber 11. The second robotic casing 20 comprises a second chamber 21. A drive unit 30 may be provided in the inner chamber 11 of the first robotic casing 10 of the robotic joint. The drive unit 30 is configured to drive the second robotic casing 20 to rotate with respect to the first robotic casing 10 around an axial direction X1. The drive unit 30 may comprise a fixed part 32 and a movable part 34 coupled to the fixed part 32. The fixed part 32 may be fixed to the first robotic casing 10 and is received in the first chamber 11. The movable part 34 is fixed to the second robotic casing 20.
[0054] As shown in Figs. 7-11, the fixed part 32 and the movable part 34 are shaped to define an axial recess 40 therebetween. Asealing apparatus 50 is arranged in the axial recess 40. In some embodiments, the movable part 34 includes a first flange 37 for coupling to the second robotic casing 20. The first flange 37 may include a plurality of screw holes 372. The movable part 34 may be fixed to the second robotic casing 20 via screw fasteners. The fixed part 32 adjacent to the first flange 37 may include a second flange 39. In some embodiments, as best shown in Figs. 8-11, the second flange 39 is a stationary portion of the gearbox 35. The axial recess 40 has a smaller diameter than an outer size of the first flange 37 of the movable part 34 and an outer size of the second flange 39 of the gearbox 35.
[0055] As shown in Figs. 7-11, the sealing apparatus 50 comprises a sleeve 54 and a sealing ring 52. The sleeve 54 may be made of a rigid material, for example, a non-metal material, such as a plastic material. The sealing ring 52 may be made of flexible material. The sleeve 54 comprises an axial hole 542 for passage of a transmission shaft 31 of the drive unit, and a sealing surface 543. The sealing ring 52 may comprise a mounting portion 524 and a sealing lip 522 protruding from the mounting portion 524. The sealing lip 522 is configured to abut against the sealing surface 544 to form an air-tight sealing interface.
[0056] In some embodiments, as shown in Figs. 7-11, the sleeve 54 may be provided on the movable part 34. The sleeve 54 is provided on the first robotic casing 10 and / or the fixed part 32. It is be understood that the shown example is merely illustrative. In some unshown embodiments, the sleeve 54 may be provided on the fixed part 32 and the sleeve 54 may be provided on the second robotic casing 20 and / or the movable part 34.
[0057] As shown in Figs. 7-11, the sleeve 54 is formed as an annular plate. The annular plate comprises an axial hole 542. The sleeve 54 comprises an annular plate body 541 extending in a radial direction perpendicular to the axial direction and defines the sealing surface 543. The sealing surface 543 extends along the radial direction. The sleeve 54 further comprises a sleeve mounting flange 547. The sleeve mounting flange 547 extends, from the annular plate body 541, inwardly in the radial direction perpendicular to the axial direction around the axial hole 542. The sleeve mounting flange 547 may comprise a plurality of mounting holes 549 for receiving screw fasteners 55. The sleeve 54 is mounted to the fixed part 32 by the screw fasteners 54. The sealing lip 522 at least radially protrudes from the mounting portion 524. The sealing lip 522 is configured to radially abut against the sealing surface 544 to form an air-tight sealing interface.
[0058] In the shown embodiment, the sleeve 54 is fixed to the fixed part 32 of the drive unit 30. In some embodiments (not shown) , the sleeve 54 may be integrally formed with one of the first robotic casing 10 and the second robotic casing 20 via injection molding.
[0059] The description of the various embodiments of the present invention have been presented for purposes of illustration, but are not intended to be exhaustive or limited to the embodiments disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The terminology used herein was chosen to best explain the principles of the embodiments, the practical application or technical improvement over technologies found in the marketplace, or to enable others of ordinary skill in the art to understand the embodiments disclosed herein.
Claims
1.A robotic joint, comprisinga first robotic casing (10) comprising an inner chamber; anda second robotic casing (20) configured to rotate with respect to the first robotic casing (10) around an axial direction;wherein the robotic joint further comprises a sealing apparatus (50) arranged between the first robotic casing (10) and the second robotic casing (20) , the sealing apparatus (50) comprising:a sleeve (54) made of a plastic material, the sleeve (54) comprising an axial hole (542) and a sealing surface (544) ; anda sealing ring (52) made of a flexible material, the sealing ring (52) comprising a mounting portion (524) and a sealing lip (522) protruding from the mounting portion (524) , the sealing lip (522) being configured to abut against the sealing surface to form a sealing interface.2.The robotic joint of claim 1, further comprising a drive unit (30) configured to drive the second robotic casing (20) to rotate with respect to the first robotic casing (10) around the axial direction, wherein the drive unit (30) comprises a fixed part (32) , fixed to the first robotic casing (10) , arranged in the chamber, and a movable part (34) fixed to the second robotic casing (20) ;wherein the sleeve (54) is provided on one of the first robotic casing (10) and the second robotic casing (20) and / or on one of the fixed part (32) and the movable part (34) of the drive unit (30) , and the sealing ring (52) is provided on the other of the first robotic casing (10) and the second robotic casing (20) and / or on the other of the fixed part (32) and the movable part (34) of the drive unit (30) .3.The robotic joint of claim 2, wherein the sleeve (54) comprises a tubular body (546) extending in the axial direction and defining the sealing surface (544) , the sealing surface (544) extending along the axial direction.4.The robotic joint of claim 2, wherein the sleeve (54) is formed as an annular plate and comprises an annular plate body (541) extending in a radial direction perpendicular to the axial direction and defining the sealing surface (543) , the sealing surface (543) extending along the radial direction.5.The robotic joint of claim 3 or 4, wherein the plastic material is selected from a group comprising of Polytetrafluoroethylene (PTFE) , Polyphenylene sulfide (PPS) preferably with glass fibers, a plastic material for producing a plastic bearing.6.The robotic joint of any one of claims 1-5, wherein the sleeve (54) is integrally formed with the one of the first robotic casing (10) and the second robotic casing (20) via injection molding.7.The robotic joint of claim 3, wherein the sleeve (54) comprises a first sleeve mounting flange (548) extending inwardly in a radial direction perpendicular to the axial direction around the axial hole (542) from the tubular body (546) , and the first sleeve mounting flange (548) is configured to attach the sleeve (54) to the one of the fixed part (32) and the movable part (34) of the drive unit (30) .8.The robotic joint of claim 7, wherein the sealing lip (522) of the sealing ring (52) at least partially extends along the axial direction and is elastically biased onto the sealing surface.9.The robotic joint of claim 7 or 8, wherein the sleeve (54) further comprises a second sleeve mounting flange (545) extending outwardly in the radial direction, and when the sleeve (54) is fixed to the one of the fixed part (32) and the movable part (34) of the drive unit (30) , the second sleeve mounting flange (545) abuts against an axial end surface of the respective robotic casing of the first and the second robotic casings (10, 20) .10.The robotic joint of claim 4, wherein the sleeve (54) comprises a sleeve mounting flange (547) extending, from the annular plate body (541) , inwardly in the radial direction perpendicular to the axial direction around the axial hole (542) , and the sleeve (54) is mounted to the one of the fixed part (32) and the movable part (34) of the drive unit (30) via the sleeve mounting flange (547) .11.The robotic joint of claim 10, wherein the sealing lip (522) of the sealing ring (52) at least partially extends along the radial direction and is elastically biased onto the sealing surface (543) .12.The robotic joint of any one of claims 2-11, whereinthe mounting portion (524) is elastically compressed in a groove (25) formed by the other of the first robotic casing (10) and the second robotic casing (20) and / or by the other of the fixed part (32) and the movable part (34) of the drive unit (30) .13.The robotic joint of any one of claims 2-11, wherein the mounting portion (524) is held by the other of the first robotic casing (10) and the second robotic casing (20) and / or by the other of the fixed part (32) and the movable part (34) of the drive unit (30) via a shape fit.14.A robot comprising a manipulator, the manipulator comprising at least one robotic joint according to any one of claims 1-13.