Sealing arrangement, and industrial robot

Abstract

A sealing arrangement (22) comprising an axial sealing element (24) configured to enclose a rotation axis (28) and dynamically seal against a surface (76) of a second part (62; 64) rotatable relative to a first part (60) around the rotation axis (28). The sealing arrangement (22) further comprises a holding element (26) configured to surround the rotation axis (28), to hold the axial sealing element (24) to the first part (60) and to counteract radial expansion of the axial sealing element (24) with respect to the rotation axis (28). An industrial robot (10) comprising a joint (16) with a sealing arrangement (22) is also provided.

Description

[0001] SEALING ARRANGEMENT, AND INDUSTRIAL ROBOT

[0002] Technical Field

[0003] The present disclosure generally relates to axial sealing elements. In particular, a sealing arrangement comprising an axial sealing element and a holding element, and an industrial robot comprising a joint with such sealing arrangement, are provided.

[0004] Background

[0005] In some processing environments, it is desirable to maintain a high level of hygiene. Examples of such processing environments include environments where food, beverages or pharmaceuticals are handled by an industrial robot. Any sanitary problem in such processing environment might result in severe consequences. For this reason, comprehensive cleaning of the robot and its surroundings is often performed on a daily basis. Typical cleaning procedures include high pressure washing with hot water containing chemical agents, such as strong acidic or alkaline detergents and disinfectants.

[0006] In order to prevent media from entering into an internal region of an industrial robot, and to prevent media in an opposite direction, an external axial seal may be provided in a joint between a first link and a second link of the industrial robot such that a rotational dynamic sealing interface is provided between the axial seal and the second link. It is known to secure such axial seal by passing bolts through bolt holes in the axial seal and tightening the axial seal against the first link. Such solution is herein referred to as a bolt-penetrated axial seal solution.

[0007] Summary

[0008] During operation of an industrial robot comprising the bolt-penetrated axial seal solution, a temperature of the axial seal may vary to a large extent, for example between 20 °C to above 80 °C. Sources for an increased temperature may include dynamic friction and heat from an electric motor driving a joint. This may cause the axial seal to soften, e.g., if made of plastic, and may cause the bolts to expand slightly, such that the axial seal thereby becomes loose.

[0009] Furthermore, with the bolt-penetrated axial seal solution, there are relatively small axial contact areas between a head of each bolt and the axial seal. The bolts thereby tend to intrude into the axial seal during tightening. As a consequence, a clamping force between the axial seal and the first link cannot be determined based on the tightening torques applied to the bolts, resulting in a deteriorated assembly.

[0010] Furthermore, with the bolt-penetrated axial seal solution, there are relatively small axial contact areas between a shaft of each bolt and the axial seal. The bolt holes in the axial seal thereby eventually deform during operation which results in the bolts losing their capacity to hold the axial seal correctly in place. Such displacement of an axial seal can be visible to a human.

[0011] Furthermore, an axial seal tends to expand radially due to thermal expansion. With the bolt-penetrated axial seal solution where only a few bolts are distributed circumferentially, the axial seal cannot be retained evenly against radial expansion, especially after the bolt holes deform. The axial seal thereby loses concentricity with respect to a rotation axis and there is a risk that a lip of the seal pops out from the dynamic sealing interface, or that the axial seal forms protrusions or depressions which deteriorate the hygienic design.

[0012] One object of the invention is to provide an improved sealing arrangement comprising an axial sealing element.

[0013] A further object of the invention is to provide an improved industrial robot comprising a joint with a sealing arrangement.

[0014] These objects are achieved by the sealing arrangement according to appended claim 1 and by the industrial robot according to appended claim 14. The invention is based on the realization that by providing a sealing arrangement where an axial sealing element is held to a first part by a holding element that surrounds a rotation axis and counteracts radial expansion of the axial sealing element, the performance of the axial sealing element to dynamically seal against a surface of a second part, rotatable relative to the first part, is improved.

[0015] According to a first aspect, there is provided a sealing arrangement comprising an axial sealing element configured to enclose a rotation axis and dynamically seal against a surface of a second part rotatable relative to a first part around the rotation axis. The sealing arrangement further comprises a holding element configured to surround the rotation axis, to hold the axial sealing element to the first part and to counteract radial expansion of the axial sealing element with respect to the rotation axis.

[0016] The holding element enables the axial sealing element to be reliably held correctly in place with respect to the first part. Due to the holding element being configured to counteract radial expansion of the axial sealing element, a dynamic sealing interface between the axial sealing element and the second part can be reliably maintained during rotation of the second part and during temperature variations. Moreover, this enables the axial sealing element to be maintained centered with respect to the rotation axis. This in turn enables a lifetime of the axial sealing element to be increased.

[0017] Moreover, due to the holding element being configured to hold the axial sealing element to the first part, the sealing arrangement enables the holding element to be tightened with bolts at higher and more accurate torques in comparison with the bolt-penetrated axial seal solution. The sealing arrangement thereby exhibits an improved resistance to performance deteriorations due to temperature variations. The holding element may act as an intermittent mounting part to clamp the axial sealing element to the first part. The axial sealing element may be concentric with the rotation axis. The axial sealing element may be made of, or include, one or more polymeric materials, such as one or more plastic materials, such as polyethylene or polytetrafluoroethylene (PTFE). The axial sealing element may or may not be monolithic. The axial sealing element may include a lip for contacting the second part at the dynamic sealing interface.

[0018] The holding element may be configured to surround the rotation axis by at least 150 degrees, such as at least 180 degrees, such as at least 270 degrees. The axial sealing element may statically seal against the first part.

[0019] The holding element may be made of metal. According to some examples, the holding element and the first part, and optionally also the second part, are made of the same type of material, such as the same type of metal.

[0020] The holding element maybe configured to enclose the rotation axis, i.e., to surround the rotation axis by 360 degrees. The sealing arrangement may be delivered as a pre-assembled package to an assembly site, where the axial sealing element encloses the holding element.

[0021] The holding element may be configured to be secured to the first part. The holding element is thereby fixed to the first part. The securing maybe made in many different ways, including with bolts, adhesive and clamps.

[0022] The holding element may comprise one or more through holes configured to be oriented substantially parallel with, or parallel with, the rotation axis. The holding element can thereby be tightened to the first part using one or more bolts, where one bolt passes through each through hole. The one or more bolts can thereby act directly on the holding element to tighten the holding element and indirectly clamping the axial sealing element, rather than acting directly on the axial sealing element. Moreover, if the holding element is made of metal, for example, the one or more bolts can be tightened to a desired torque which provides for a reliable clamping of the axial sealing element. The holding element may be enclosed by the axial sealing element. In these cases, the axial sealing element may overlap the holding element along the rotation axis. As an alternative, the holding element may be offset from the axial sealing element along the rotation axis.

[0023] The holding element may be a holding ring. Thus, the holding element may be annular and configured to enclose the rotation axis. In these cases, the holding element may be configured to be concentric with the rotation axis.

[0024] The surface may be substantially transverse to, or transverse to, the rotation axis. A surface substantially transverse to the rotation axis may be angled at least 45 degrees, such as at least 6o degrees, such as at least 75 degrees, to the rotation axis.

[0025] The axial sealing element may comprise a primary radially locking profile enclosing the rotation axis. In these cases, the holding element may comprise a secondary radially locking profile enclosing the rotation axis and engaging the primary radially locking profile. This enables a relatively large contact area between the holding element and the axial sealing element which counteracts local stresses and consequential crack initiation in, and oval expansion of, the axial sealing element. As a consequence, the axial sealing element will be more correctly positioned with respect to the second part during operation and during temperature variations and the lifetime of the axial sealing element will be increased.

[0026] Also the engagement between the primary and secondary radially locking profiles may enclose the rotation axis. Thus, the secondary radially locking profile may engage the primary radially locking profile along an annular interface. A width of this annular interface may be at least 1 %, such as at least 2 %, of an inner radius of the axial sealing element. An offset along the rotation axis between the lip and the annular interface may be less than the width of the annular interface, both before and after the lip contacts the second part. In some examples, the lip is positioned within the annular interface along the rotation axis, both before and after the lip contacts the surface. This may in particular contribute to maintaining the lip in a desired position with respect to the second part.

[0027] The primary radially locking profile may include a male radially locking profile and the secondary radially locking profile may include a female radially locking profile.

[0028] Each of the primary radially locking profile and the secondary radially locking profile may include a conical profile. The use of conical primary and secondary radially locking profiles enables a self-centering effect of the axial sealing element with respect to the rotation axis during tightening of the holding element to the first part, enables the axial sealing element to be maintained centered with respect to the rotation axis when the second part rotates relative to the first part, and enables the axial sealing element to be retained against radial expansion.

[0029] As an alternative to radial primary and secondary radially locking profiles, each of the primary and secondary radially locking profile may include an annular step.

[0030] The axial sealing element may be rotationally locked to the holding element with respect to the rotation axis. Due to this rotational locking, the performance of the axial sealing element is improved and more predictable. For example, deformation of the axial sealing element, such as due to local stresses, is reduced, and loads on one or more bolts for tightening the holding element can be reduced.

[0031] The axial sealing element may comprise a wave-formed primary rotationally locking profile enclosing the rotation axis. In these cases, the holding element may comprise a wave-formed secondary rotationally locking profile enclosing the rotation axis and engaging the primary rotationally locking profile. The use of wave-formed primary and secondary rotationally locking profiles reduces local stresses in the axial sealing element, contributing to an increased lifetime thereof, while still enabling a reliable rotational locking therebetween. Each of the primary and secondary rotationally locking profile may comprise at least two sets of peaks and valleys. For each of the primary and secondary rotationally locking profiles, a radial distance between the peaks and valleys maybe at least 2 % and / or less than 8 %, such as 5 %, of an outer radius of the axial sealing element.

[0032] According to a second aspect, there is provided an industrial robot comprising a joint with a sealing arrangement according to the first aspect, the first part and the second part.

[0033] The holding element may be secured to the first part by fasteners. The fasteners may be bolts.

[0034] An external axial sealing element surface of the axial sealing element may be substantially flush with, or flush with, a first external surface of the first part and a second external surface of the second part. Each of the first and second external surfaces may be cylindrical. The external axial sealing element surface of the axial sealing element may or may not be cylindrical.

[0035] A proximal link of the industrial robot may constitute the first part, and a distal link of the industrial robot or a part secured to the distal link, may constitute the second part. The industrial robot may be a hygienic industrial robot. To this end, the industrial robot may meet the IEC (International Electrotechnical Commission) standard 60529 and / or the IP69K rating according to the German standard DIN 40050-9.

[0036] Brief Description of the Drawings

[0037] Further details, advantages and aspects of the present disclosure will become apparent from the following description taken in conjunction with the drawings, wherein:

[0038] Fig. 1: schematically represents a side view of an industrial robot comprising a sealing arrangement;

[0039] Fig. 2: schematically represents a cross-sectional side view of the sealing arrangement; Fig. 3: schematically represents an enlarged view of section A in Fig. 2;

[0040] Fig. 4: schematically represents an end view of an axial sealing element;

[0041] Fig. 5: schematically represents a perspective view of a holding element;

[0042] Fig. 6: schematically represents an end view of the holding element;

[0043] Fig. 7: schematically represents an end view of the sealing arrangement;

[0044] Fig. 8: schematically represents a partial cross-sectional side view of a joint of the industrial robot; and

[0045] Fig. 9: schematically represents a partial cross-sectional side view of a further example of a joint of the industrial robot.

[0046] Detailed Description

[0047] In the following, a sealing arrangement comprising an axial sealing element and a holding element, and an industrial robot comprising a joint with such sealing arrangement, will be described. The same or similar reference numerals will be used to denote the same or similar structural features.

[0048] Fig. 1 schematically represents a side view of an industrial robot 10. The industrial robot 10 of this example is a hygienic robot, e.g., for handling food, beverages and / or pharmaceuticals. The industrial robot 10 of this example meets the IP69K rating according to the German standard DIN 40050-9. The IP rating may however be lower in some implementations.

[0049] The industrial robot 10 of this specific and non-limiting example comprises a base 12, a first link 14a rotatable relative to the base 12 at a first joint 16a, a second link 14b rotatable relative to the first link 14a at a second joint 16b, a third link 14c rotatable relative to the second link 14b at a third joint 16c, a fourth link 14b rotatable relative to the third link 14c at a fourth joint i6d, a fifth link 14c rotatable relative to the fourth link 14b at a fifth joint i6e, a sixth link i4f rotatable relative to the fifth link 14c at a sixth joint i6f, and an end effector 18, here fixed to the sixth link 14b One, several or all of the joints i6a-i6f may also be referred to with reference numeral "16". Fig. 1 further shows an external region 20 outside of the industrial robot 10. Fig. 1 further shows a sealing arrangement 22. The industrial robot 10 comprises one or more such sealing arrangements 22. Each sealing arrangement 22 maybe provided at one of the joints 16.

[0050] Fig. 2 schematically represents a cross-sectional side view of the sealing arrangement 22. The sealing arrangement 22 comprises an axial sealing element 24 and a holding ring 26. The holding ring 26 is one example of a holding element.

[0051] Fig. 2 further shows a rotation axis 28 enclosed by the axial sealing element 24. Unless otherwise indicated, a radial direction, an axial direction, a rotational direction and a circumferential direction are used with respect to the rotation axis 28. The rotation axis 28 maybe associated with the joint 16 where the sealing arrangement 22 is installed. For example, when the sealing arrangement 22 is installed in the fourth joint i6d, the fourth link 14b may rotate relative to the third link 14c around the rotation axis 28.

[0052] The axial sealing element 24 of this example is concentric with the rotation axis 28. The axial sealing element 24 of this example is made of polyethylene. The axial sealing element 24 comprises an external axial sealing element surface 30. The external axial sealing element surface 30 may or may not be cylindrical. In any case, the external axial sealing element surface 30 is here concentric with the rotation axis 28.

[0053] The axial sealing element 24 and the holding ring 26 may optionally be delivered as a pre-assembled package in the state shown in Fig. 2, where the axial sealing element 24 encloses the holding ring 26. As shown, the axial sealing element 24 of this example overlaps the holding ring 26 along the rotation axis 28. Fig. 2 further shows an outer radius 32 and an inner radius 34 of the axial sealing element 24.

[0054] The holding ring 26 of this example is annular and concentric with the rotation axis 28. Thus, the holding ring 26 here encloses the rotation axis 28. The holding ring 26 of this example is made of metal, such as stainless steel. The holding ring 26 comprises a plurality of, here eight, through holes 36. Each through hole 36 runs in parallel with the rotation axis 28 through the holding ring 26.

[0055] Fig. 3 schematically represents an enlarged view of the sealing arrangement 22 in section A in Fig. 2. As shown, the axial sealing element 24 comprises a lip 38. Moreover, in the sealing arrangement 22 of this example, the axial sealing element 24 comprises a male primary radially locking profile 40 and the holding ring 26 comprises a female secondary radially locking profile 42. Each of the primary and secondary radially locking profiles 40, 42 of this example is conical and encloses the rotation axis 28.

[0056] The secondary radially locking profile 42 engages the primary radially locking profile 40 along an annular interface 44 enclosing the rotation axis 28 in a concentric relationship therewith. The primary and secondary radially locking profiles 40, 42 provide a shape-locking coupling between the axial sealing element 24 and the holding ring 26. The holding ring 26 thereby retains the axial sealing element 24 evenly against radial expansion, e.g., due to a temperature increase.

[0057] The conicities of the primary and secondary radially locking profiles 40, 42 enable a large contact area between the primary and secondary radially locking profiles 40, 42, thereby minimizing local stresses on the axial sealing element 24, which in turn increases the lifetime of the axial sealing element 24. Moreover, this design prevents the axial sealing element 24 from expanding into an oval shape and maintains concentricity of the axial sealing element 24.

[0058] The annular interface 44 has a width 46. In some examples, the width 46 corresponds to a width of the primary radially locking profile 40 and / or of the secondary radially locking profile 42. The width 46 is here approximately 3 % of the inner radius 34.

[0059] The lip 38 in this example is positioned within the annular interface 44 along the rotation axis 28 in the state of the sealing arrangement 22 shown in Fig. 3. That is, the lip 38 is positioned radially outside of the annular interface 44 and is axially aligned with the annular interface 44.

[0060] Fig. 4 schematically represents an end view of the axial sealing element 24. The axial sealing element 24 of this example comprises a wave-formed primary rotationally locking profile 48 facing radially inwards and enclosing the rotation axis 28. The primary rotationally locking profile 48 comprises a plurality of sets, here eight, of a primary peak 50 and a primary valley 52. A radial distance between the primary peaks 50 and the primary valleys 52 is here approximately 5 % of the outer radius 32.

[0061] Fig. 5 schematically represents a perspective view of the holding ring 26, and Fig. 6 schematically represents an end view of the holding ring 26. The holding ring 26 of this example comprises a wave-formed secondary rotationally locking profile 54 facing radially outwards and enclosing the rotation axis 28. The shape of the secondary rotationally locking profile 54 corresponds to the shape of the primary rotationally locking profile 48. The secondary rotationally locking profile 54 comprises a plurality of sets, here eight, of a secondary peak 56 and a secondary valley 58. As shown in Fig. 5, the secondary radially locking profile 42 here partially overlaps the secondary rotationally locking profile 54 in a direction parallel with the rotation axis 28.

[0062] Fig. 7 schematically represents an end view of the sealing arrangement 22. As shown, the secondary rotationally locking profile 54 engages the primary rotationally locking profile 48 around the rotation axis 28. Each primary peak 50 is seated in a secondary valley 59 and each secondary peak 56 is seated in a primary valley 52. The holding ring 26 thereby retains the axial sealing element 24 against rotation.

[0063] The use of wave-formed primary and secondary rotationally locking profiles 48, 54 enables local stresses in the axial sealing element 24 to be reduced. The amplitude (here the radial extension) and the wavelength (e.g., number of sets of peaks and valleys) of the primary and secondary rotationally locking profiles 48, 54 may be varied for different implementations. Fig. 8 schematically represents a partial cross-sectional side view a joint 16-1 for the industrial robot io. The joint 16-1 may for example be any of the joints i6a-i6f. The joint 16-1 comprises the sealing arrangement 22 installed therein. The joint 16-1 of this example comprises a proximal body 60, a distal body 62 and an adapting ring 64 fixed to the distal body 62, here by distal bolts 66. In this example, the distal body 62 and the adapting ring 64 may form one of the links I4b-i4f of the industrial robot 10, and the proximal body 60 may be constituted by one of the links 143-140 of the industrial robot 10. The distal body 62 and the adapting ring 64 are rotatable relative to the proximal body 60 around the rotation axis 28. Fig. 8 further shows an internal region 68 inside of the industrial robot 10.

[0064] The proximal body 60 and the adapting ring 64 are here examples of a first part and a second part, respectively. The proximal body 60, the distal body 62, and the adapting ring 64 comprise a proximal body surface 70, a distal body surface 72 and an adapting ring surface 74, respectively. The proximal body surface 70 is an example of a first external surface. The adapting ring surface 74 is an example of a second external surface. In this example, the proximal body surface 70, the adapting ring surface 74 and the distal body surface 72 are cylindrical surfaces of a common external diameter and concentric with the rotation axis 28. As shown in Fig. 8, the external axial sealing element surface 30 is flush with each of the proximal body surface 70 and the adapting ring surface 74. The joint 16-1 thereby has a very hygienic design without steps or gaps. To provide the external axial sealing element surface 30 flush with each of the proximal body surface 70 and the adapting ring surface 74, at least the axially outer surfaces of the external axial sealing element surface 30 maybe concentric with the adapting ring surface 74 and the proximal body surface 70, respectively.

[0065] Each of the proximal body 60, the adapting ring 64 and the distal body 62 is here made of metal, such as stainless steel.

[0066] The adapting ring 64 comprises an axial surface 76. The axial surface 76 of this example is oriented transverse to the rotation axis 28. The axial surface 76 is one example of a surface of a second part. In operation of the joint 16-1 of this example, the lip 38 dynamically seals against the axial surface 76 at a dynamic sealing interface 78 and statically seals against the proximal body 60. The proximal body 60 comprises a plurality of threaded holes 80.

[0067] The joint 16-1 of this example further comprises a transmission 82 and an electric motor 84. The electric motor 84 is arranged to rotationally drive the distal body 62 relative to the proximal body 60 around the rotation axis 28 via the transmission 82.

[0068] The sealing arrangement 22 of this example comprises a plurality of sealing arrangement bolts 86. Each sealing arrangement bolt 86 is one example of a fastener.

[0069] In Fig. 8, the holding ring 26 has been secured to the proximal body 60 by threadingly engaging the threaded holes 80 with respective sealing arrangement bolts 86 passing through the respective through holes 36. The sealing arrangement bolts 86 thus act directly on the holding ring 26 and do not contact the axial sealing element 24. Due to the rigidity of the holding ring 26, here made of metal, the tightening torques of the sealing arrangement bolts 86 can be high and accurately obtained.

[0070] During tightening of the sealing arrangement bolts 86, the holding ring 26 moves towards the proximal body 60 and the axial sealing element 24 will be forced into concentricity with the rotation axis 28 due to the forcing of the primary radially locking profile 40 by the secondary radially locking profile 42. The axial sealing element 24 thereby self-centers with respect to the rotation axis 28.

[0071] The axial sealing element 24 is then held to the proximal body 60 by the holding ring 26 and the holding ring 26 counteracts radial expansion of the axial sealing element 24, e.g., due to temperature variations between 20 °C and 80 °C. In addition, the engagement between the primary and secondary rotationally locking profiles 48, 54 prevents rotation of the axial sealing element 24. The axial sealing element 24 can thereby reliably be held in a correct position in relation to the adapting ring 64 during operation of the joint 16-1. This contributes both to an improved performance and an increased lifetime of the axial sealing element 24.

[0072] As can be gathered from Fig. 8, the lip 38 is positioned within the annular interface 44 along the rotation axis 28 also when sealing against the axial surface 76. This alignment of the lip 38 and the annular interface 44 along the rotation axis 28 particularly contributes to maintaining the lip 38 in a correct position during temperature variations. The particular manner of securing the axial sealing element 24 to the proximal body 60 using the holding ring 26 as described herein thus provides several advantages.

[0073] Fig. 9 schematically represents a partial cross-sectional side view of a further example of a joint 16-2 for the industrial robot 10. Mainly differences with respect to the joint 16-1 will be described. The joint 16-2 of this example comprises the proximal body 60 and the distal body 62, but not the adapting ring 64. The axial surface 76 is here provided on the distal body 62. The distal body 62 and the distal body surface 72 are thus further examples of a second part and a second external surface, respectively. In these cases, the axial surface 76 may for example be hardened.

[0074] The designs in Fig. 8 and 9 may be combined. Thus, the industrial robot 10 may comprise both one or more joints 16-1 and one or more joints 16-2. Also one or both joints 16-1, 16-2 may also be referred to with reference numeral "16".

[0075] While the present disclosure has been described with reference to exemplary embodiments, it will be appreciated that the present invention is not limited to what has been described above. For example, it will be appreciated that the dimensions of the parts maybe varied as needed. Accordingly, it is intended that the present invention may be limited only by the scope of the claims appended hereto.

Claims

CLAIMS1. A sealing arrangement (22) comprising:- an axial sealing element (24) configured to enclose a rotation axis (28) and dynamically seal against a surface (76) of a second part (62; 64) rotatable relative to a first part (60) around the rotation axis (28); characterized in that the sealing arrangement (22) further comprises:- a holding element (26) configured to surround the rotation axis (28), to hold the axial sealing element (24) to the first part (60) and to counteract radial expansion of the axial sealing element (24) with respect to the rotation axis (28).

2. The sealing arrangement (22) according to claim 1, wherein the holding element (26) is configured to enclose the rotation axis (28).

3. The sealing arrangement (22) according to any of the preceding claims, wherein the holding element (26) is configured to be secured to the first part (60).

4. The sealing arrangement (22) according to any of the preceding claims, wherein the holding element (26) comprises one or more through holes (36) configured to be oriented substantially parallel with the rotation axis (28).

5. The sealing arrangement (22) according to any of the preceding claims, wherein the holding element (26) is enclosed by the axial sealing element (24).

6. The sealing arrangement (22) according to any of the preceding claims, wherein the holding element (26) is a holding ring.

7. The sealing arrangement (22) according to claim 6, wherein the holding element (26) is configured to be concentric with the rotation axis (28).

8. The sealing arrangement (22) according to any of the preceding claims, wherein the surface (76) is substantially transverse to the rotation axis (28).

9. The sealing arrangement (22) according to any of the preceding claims, wherein the axial sealing element (24) comprises a primary radially locking profile (40) enclosing the rotation axis (28), wherein the holding element (26) comprises a secondary radially locking profile (42) enclosing the rotation axis (28) and engaging the primary radially locking profile (40).

10. The sealing arrangement (22) according to claim 9, wherein the primary radially locking profile (40) includes a male radially locking profile and the secondary radially locking profile (42) includes a female radially locking profile.

11. The sealing arrangement (22) according to claim 9 or 10 wherein each of the primary radially locking profile (40) and the secondary radially locking profile (42) includes a conical profile.

12. The sealing arrangement (22) according to any of the preceding claims, wherein the axial sealing element (24) is rotationally locked to the holding element (26) with respect to the rotation axis (28).

13. The sealing arrangement (22) according to claim 12, wherein the axial sealing element (24) comprises a wave-formed primary rotationally locking profile (48) enclosing the rotation axis (28), and wherein the holding element (26) comprises a wave-formed secondary rotationally locking profile (54) enclosing the rotation axis (28) and engaging the primary rotationally locking profile (48).

14. An industrial robot (10) comprising a joint (16) with the sealing arrangement (22) according to any of the preceding claims, the first part (60) and the second part (62; 64).15- The industrial robot (10) according to claim 14, wherein an external axial sealing element surface (30) of the axial sealing element (24) is substantially flush with a first external surface (70) of the first part (60) and a second external surface (72; 74) of the second part (62; 64).

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