Rotor for an electric motor, electric motor with such a rotor and method for manufacturing such a rotor

Abstract

The rotor of an electric motor has a housing on the inside of which at least one magnet is held. It is held in the housing by at least one retaining element, which secures the magnet at least axially within the housing and is connected to the housing by at least one friction stir weld. The retaining element is firmly bonded to the housing by means of a friction stir welding process, thereby forming the friction stir weld that exists between the retaining element and the housing.

Description

[0001] The invention relates to a rotor for an electric motor according to the preamble of claim 1, an electric motor with such a rotor according to claim 20, and a method for manufacturing such a rotor according to claim 21.

[0002] For example, in external rotor EC electric motors, magnets are attached to the inside of a cylindrical housing using an adhesive process. This adhesive process requires considerable technical effort, as it necessitates extraction systems and the handling of the adhesive is complex. Furthermore, the adhesive process is associated with significant costs. To ensure the magnets are correctly positioned and bonded to the rotor, certain requirements must be met regarding the magnet geometry, which involves comparatively expensive grinding operations. The adhesive process also raises sustainability concerns, and recyclability is compromised as a result of the adhesive process.

[0003] The invention is based on the objective of designing the generic rotor, the electric motor and the method for manufacturing the rotor in such a way that cost-effective, reliable manufacturing of the rotor is possible, meeting the requirements for sustainability and recyclability.

[0004] This problem is solved according to the invention in the case of the generic rotor with the characterizing features of claim 1, in the case of the electric motor with the features of claim 20 and in the case of the method with the features of claim 21.

[0005] In the rotor according to the invention, the magnet is secured axially by the locking element, preferably clamped axially in the housing. The locking element is firmly bonded to the housing by means of a friction stir welding process, thereby forming the friction stir weld seam that exists between the locking element and the housing. The friction stir welding process is cost-effective, environmentally friendly, and energy-saving. Since the magnet is no longer glued, it is readily recyclable.

[0006] Since the magnet is not attached to the rotor with an adhesive, a corresponding adhesive gap is no longer required. This leads to a reduction in electromagnetic excitation in the magnetic circuit. Furthermore, the elimination of the adhesive gap allows the magnet to be manufactured with tighter tolerances, which also contributes to a reduction in electromagnetic excitation in the magnetic circuit.

[0007] The elimination of the adhesive has the advantage that corresponding adhesive devices, extraction systems, storage for the adhesive and the like are not required, making the production of the rotor according to the invention cost-effective.

[0008] It is advantageous if the locking element is designed as a ring. The ring allows the magnet to be easily secured in the housing.

[0009] It is also possible, in principle, to assemble the locking element from individual sections, preferably ring sections, each of which is individually connected to the housing by friction stir welding. Such a design of the locking element is advantageous when the rotor has a correspondingly large diameter.

[0010] A structurally simple design and manufacturing of the rotor are advantageously possible if the housing has a rim enclosing a receiving space into which the locking element is inserted. Since the receiving space is located at the housing rim, the locking element can be easily inserted into it during the manufacturing process.

[0011] A secure and reliable connection and fastening is advantageously achieved when the locking element rests with its outer surface against an inner surface of the housing edge. Such a design is particularly advantageous when the locking element is shaped like a ring. In this case, the annular locking element rests with its outer surface against the inner surface of the housing edge.

[0012] For a secure connection and fastening, it is advantageous if the friction stir weld extends over the outside of the locking element and the inside of the housing rim. The friction stir welding process softens and bonds the material of the locking element and the housing rim together. In this way, the friction stir weld extends radially into both the housing rim and the locking element.

[0013] Depending on the rotor design and / or requirements, the friction stir weld is designed to extend at least over a portion of the thickness of the locking element and the housing edge. This allows the axial thickness of the friction stir weld to be adapted to the specific requirements. It is also possible to design the friction stir weld to extend over the entire axial thickness of the locking element up to the magnet being secured.

[0014] The magnet can be arranged on the inside of the housing with at least one return element in between.

[0015] The friction stir weld advantageously extends over the circumference of the housing rim. This ensures a secure attachment of the locking element to the housing around the entire rim. The locking element can be ring-shaped or consist of individual ring segments joined together to form a ring-shaped locking element.

[0016] Alternatively, the friction stir weld can also be formed by individual weld sections spaced apart around the circumference of the housing edge. In this case, the friction stir weld does not need to extend over the entire circumference of the housing edge. This design is particularly suitable when the housing edge has a large diameter. In this case, it may be sufficient to provide the connection between the locking element and the housing edge in sections.

[0017] A secure fastening, in particular clamping of the magnets, is preferably achieved when the locking element rests against the end face of the at least one magnet.

[0018] In order to facilitate the later use of the rotor in an advantageous manner, the end faces of the housing edge and the locking element lie in a common radial plane of the rotor.

[0019] It is advantageous if the magnet is secured axially between the locking element and an axial stop in the housing. The axial stop can be formed, for example, by a projection on the base of the housing. The locking element can press the magnet axially against the axial stop of the housing, so that the magnet is held securely in the housing even without an adhesive.

[0020] Advantageously, the rotor has several magnets arranged in at least one row in the circumferential direction of the housing.

[0021] In another advantageous embodiment, instead of individual magnets, at least one magnetic ring is provided which extends over the circumference of the housing.

[0022] For easier assembly, it is advantageous if the magnets are also secured radially by the locking element. In this case, the locking element serves not only to clamp the magnets axially, but also to position them radially within the housing.

[0023] To facilitate this radial alignment in a simple manner, it is advantageous if the locking element has at least one alignment part that rests against the side of the magnet facing away from the housing. This alignment part, which can advantageously be formed integrally with the locking element, reliably holds or positions the magnets radially within the housing.

[0024] It is particularly advantageous if the alignment element is designed as an annular projection. This allows all magnets arranged circumferentially one behind the other in the housing to be radially positioned in a single operation using the annular projection.

[0025] In a further preferred embodiment, the magnets are also aligned circumferentially within the housing by the locking element. This design of the locking element ensures that it can be used not only for axially securing or clamping the magnets, but also for aligning them circumferentially within the housing during assembly. If, in addition, the locking element is advantageously also used for radially positioning the magnets, then the locking element has a triple function, for which only a single component is required. This results in very simple and cost-effective assembly of the individual parts during the manufacture of the rotor according to the invention.

[0026] In order to advantageously achieve alignment in the circumferential direction of the housing, the locking element has at least one positive locking element on its end face facing the magnet, against which the magnet rests in the circumferential direction of the housing and which prevents or at least limits rotation of the magnet in the circumferential direction of the housing.

[0027] A significant improvement in the clamping effect of the locking element is advantageously achieved if the magnet has at least one receptacle on its end face for a portion of the material softened by friction stir welding. During axial pressing of the magnets, this softened material is pressed into this receptacle, contributing to a secure attachment of the locking element to the magnets. The receptacle on the end face of the magnets can be designed in various ways. It can be a groove-shaped recess, a blind hole, or the like.

[0028] The electric motor, which is in particular an EC external rotor motor, has, in addition to the stator, the rotor according to the invention.

[0029] In the method according to the invention, the at least one locking element is firmly connected to the housing by a friction stir welding process. The magnet(s) are first inserted into the housing and axially secured by the locking element, preferably clamped in the axial direction within the housing.

[0030] The subject matter of the application is not only defined by the subject matter of the individual patent claims, but also by all information and features disclosed in the drawings and the description. These are claimed as essential to the invention, even if they are not explicitly stated in the claims, insofar as they are novel, individually or in combination, compared to the prior art.

[0031] Further features of the invention will become apparent from the further claims, the description and the drawings.

[0032] The invention will be explained in more detail with reference to some embodiments illustrated in the drawing. These show Fig. 1 a front view of a rotor of an external rotor motor according to the invention, Fig. 2 a cut along line AA in Fig. 1, Fig. 3 in enlarged view in axial section a part of a mounting of a magnet of the rotor according to Fig. 1, Fig. 4 in a representation according to Fig. 3 another embodiment of the fastening of a magnet of the rotor according to the invention Fig. 1, Fig. 5 in axial section a force-fit connection of the magnets of the rotor according to the invention, Fig. 6 in a representation accordingly Fig. 5 a form-fit and, if necessary, a force-fit connection of the magnets of the rotor according to the invention, Fig. Figures 7a to 7e show in perspective and front view several embodiments for possible surface structures of the magnets for an additional positive locking within the rotor according to the invention. Fig. 8a to 8c different designs of retaining rings, each in end view and in axial section, Fig. 9a and Fig. 9b further embodiments of retaining rings of the rotor according to the invention, shown in frontal view and perspective view, Fig. 10 an axial section through an external rotor motor, Fig. 11 in perspective view the external rotor motor according to Fig. 10, Fig. 12 in perspective view a magnetic ring with a locking ring, Fig. 13 an axial section through the magnetic ring according to Fig. 12.

[0033] The Fig. 1 and Fig. Figure 2 shows a simplified representation of the rotor of an EC electric motor in external rotor design ( Fig. 10 and Fig. 11) The rotor has a cylindrical housing 1 which transitions at one end into a base 2 located radially to it. The housing 1 and the base 2 are advantageously formed in one piece.

[0034] On the inside of the base 2, a thickening 3 is provided in the center, into which one end of a rotor shaft 40 is inserted in a known manner ( Fig. 10) is inserted. In the installed position, this rotor shaft 40 is rotatably mounted in a stator bushing 41 of a stator 42. The stator bushing 42 projects from a radial base 43 of an electronics housing 44 of the stator 42. The housing 1 of the rotor is open towards the base 43 of the electronics housing 44 of the stator 42.

[0035] The Fig. 10 and Fig. Figure 11 merely shows the basic structure of an external rotor motor. These figures do not show the rotor design according to the invention.

[0036] On the inside of the housing 1 there is an annular return part 4, which is attached to the inner wall of the housing 1 in a suitable manner.

[0037] Magnets 5 are provided on the inside of the return section 4, arranged in two rows side by side and one behind the other. The two rows of magnets 5a, 5b lie axially adjacent to each other. The row of magnets 5b adjacent to the base 2 is axially supported by an axial stop 6, which is advantageously an annular projection of the base 2. The projection 6 is advantageously formed integrally with the base 2 and extends annularly around the axis of the rotor housing 1.

[0038] The return part 4 projects with one end into a ring recess 7, which is provided between the ring projection 6 of the base 2 and the cylindrical housing 1 and against whose side walls the return part 4 rests.

[0039] In the magnet rows 5a, 5b, the magnets 5 are arranged one behind the other in the circumferential direction.

[0040] Advantageously, the magnets 5 in the two magnet rows 5a and 5b are identically designed ( Fig. 2) Preferably, the magnets 5 in the two magnet rows 5a, 5b are arranged such that the magnets 5 in the magnet rows 5a, 5b are arranged without offset to each other in the circumferential direction.

[0041] The magnets 5 of the magnet series 5a do not project axially beyond the housing 1. The end faces 8 and 9 of the magnet series 5a and of the return part 4 advantageously lie in a common radial plane.

[0042] For axial securing of the return part 4, the free edge 10 of the housing 1 is thickened radially inwards in such a way that it overlaps the return part 4 and thus secures it axially.

[0043] The housing 1 is provided on its outer surface with a radial flange 11, to which fan blades 45 are attached. These can advantageously be formed in one piece, but can also be attached to the housing. The fan blades 45 extend radially outwards, and are either flat or curved across their radial width. Radial extension here means that the fan blades lie exactly in the radial direction, but can also be perpendicular to the radial direction.

[0044] Fig. Figure 3 shows, in an enlarged view, the axial locking of the return part 4 and the magnets 5 of the magnet series 5a. The free edge 10 of the housing 1 overlaps the return part 4 and extends to the magnets 5.

[0045] A retaining ring 12 serves to axially secure the magnets 5, and advantageously extends over the circumference of the magnet row 5a.

[0046] In contrast to the advantageous ring shape, the retaining ring 12 can also consist of individual ring sections which are assembled into a ring during the assembly process described below. These ring sections can also be arranged one behind the other at a distance.

[0047] For the sake of simplicity, the ring-shaped design of the locking element 12 is described below.

[0048] The retaining ring 12 has a cylindrical outer surface 13, which rests against a cylindrical inner surface 14 of the thickened rim of the housing 1. The inner surface 14 encloses a receiving space 33 into which the retaining ring 12 is inserted.

[0049] In the area of ​​its cylindrical inner surface 15, the retaining ring 12 has an annular axial projection 16 which bears against the inner surface 17 of the magnets 5 of the magnet series 5a. The projection 16 is significantly shorter in the axial direction than the magnets 5 of the magnet series 5a. The projection 16 is designed such that the magnets 5 are held in contact with the cylindrical return part 4 by the projection 16.

[0050] The retaining ring 12 is designed so that its outer surface 13 rests against the inner surface 14 of the housing edge 10 and its projection 16 rests against the magnet 5.

[0051] The end face 18 of the housing edge 10 and the end face 19 of the retaining ring 12 are each flat and lie in a common radial plane of the rotor.

[0052] The retaining ring 12 is permanently joined to the housing 1 by means of a friction stir welding process. This process is known and therefore will not be described in detail. This welding process creates the weld seam 20, which is formed in the area of ​​the adjacent outer surfaces 13 and 14 of the retaining ring 12 and the housing 1.

[0053] The weld seam 20 extends only over a part of the thickness of the edge 10 of the housing 1 or of the retaining ring 12.

[0054] In the embodiment according to Fig. 4 The weld seam 20 is provided over the entire thickness of the housing edge 10 and the retaining ring 12 and extends to the magnets 5 and the return part 4. In this embodiment, a large weld penetration depth is thus provided, while Fig. Figure 3 shows an embodiment with a lower welding depth.

[0055] Friction stir welding allows the return element 4 and the retaining ring 12 to be reliably and firmly joined to the housing 1. The retaining ring 12 is advantageously designed and positioned such that it presses the magnets 5 of the two magnet rows 5a, 5b axially against the projection 6 of the base, thus clamping the magnets 5 axially.

[0056] Friction stir welding can be carried out such that the weld seam 20 extends over the circumference of the retaining ring 12. However, it is also possible to perform the welds at points distributed around the circumference of the retaining ring 12.

[0057] If the retaining ring is formed by individual ring sections, then these ring sections are each connected to the housing 1 by means of friction stir welding.

[0058] The positioning of the weld seam 20, the depth of the weld seam and the extent of the weld seam are process parameters that are selected according to the design of the rotor so that the magnets 5 are held securely in the rotor 1.

[0059] Friction stir welding produces high-quality welded joints with excellent fatigue properties.

[0060] The housing 1 and the retaining ring 12 are advantageously made of aluminum, which is ideally suited for friction stir welding. Dissimilar materials such as aluminum and steel, as well as materials that are difficult to weld or are incompatible, such as magnesium, copper, or titanium, can also be joined using friction stir welding. Since friction stir welding involves only minimal heat input, no or very few cracks or pores form in the material. The weld 20 is characterized by high strength and minimal distortion.

[0061] In the Fig. 3 and Fig. 4 the magnets 5 are designed such that they have a flat front face 21, against which the retaining ring 12 with a correspondingly flat inner surface 22 lies flat.

[0062] The Fig. 5 and Fig. Figure 6 shows the possibility of forming the connection between the retaining ring 12 and the housing 1 and the magnets 5 exclusively by frictional engagement, as exemplified in Fig. Figure 5 shows this rotor design. Fig. 2. The cylindrical inner surface 15 of the retaining ring 12 essentially forms an axial extension of the inner surface 17 of the magnets 5.

[0063] During training according to Fig. 6, which are trained according to the Fig. 3 and Fig. 4 corresponds to the retaining ring 12 being provided with the projection 16 in the manner described, which rests on the inside 17 of the magnets 5 and thus leads to a positive fit between the retaining ring 12 and the magnets 5 in addition to the force fit via the weld seam 20.

[0064] In Fig. In section 5, the dimensions I and s are specified. Dimension I indicates the thickness of the retaining ring 12, and dimension s indicates the width of the retaining ring 12. Typical values ​​for dimensions I and s are 0.1 mm to 300 mm.

[0065] Fig. Figure 7 shows different possibilities for the end-face design of the magnets 5, which are located in the magnet series 5a.

[0066] Fig. Figure 7e shows the formation of the flat end face 21 of the magnet 5, which rests against the inner side 22 of the retaining ring 12, as can be seen from the Fig. 3 and Fig. 4 has been described. The formation of the magnets 5 according to the Fig. 7a to 7d enables an additional positive locking between the magnets 5 and the retaining ring 12 after friction stir welding.

[0067] The magnet 5 according to Fig. 7a has a groove 23 extending across its circumference in its end face 21. This groove has a rectangular cross-section and is located at half the thickness of the end face 21. The groove 23 runs parallel to the inner surface 17 of the magnet, which in turn runs parallel to the outer surface 24 of the magnet 5. In the installed position, the magnets 5, with their curved outer surface 24, lie flat against the inner surface of the annular return part 4.

[0068] The groove 23 has a constant width along its length and extends to the narrow sides 25, 26 of the magnet 5. The groove 23 is open to the narrow sides 25, 26.

[0069] In friction stir welding, the material of the housing 1 and the retaining ring 12, which is softened during the welding process, is pressed into the groove 23, thereby achieving an additional positive locking to secure the magnets 5.

[0070] In the embodiment according to Fig. 7b has the groove 23 with a partially circular, advantageously semicircular, cross-section. Otherwise, the magnet 5 is designed in the same way as in the embodiment according to Fig. 7a.

[0071] The magnet 5 according to Fig. 7c has a groove 23 in its end face 12, which has a triangular cross-section. Otherwise, the magnet 5 is designed identically to the embodiment shown in [reference to embodiment]. Fig. 7a.

[0072] The magnet 5 according to Fig. Magnet 7d has individual recesses 27 in its end face 21 instead of a continuous groove. The recesses 27 have, for example, a circular cross-section and are spaced apart from each other in the circumferential direction. Advantageously, the recesses 27 are located at half the thickness of the magnet 5. Depending on the requirements, the recesses 27 can also be arranged distributed across the end face 21 of the magnet both circumferentially and vertically.

[0073] The recesses 27 can have any suitable cross-section. The material of the housing 1 and the retaining ring 12, softened during friction stir welding, is pressed into the recesses 27 during the welding process, thereby creating a positive-locking connection.

[0074] The retaining ring 12 can have a wide variety of geometries for positioning the magnets 5 of the magnet series 5a in order to position the magnets in the housing 1 in the required manner.

[0075] Fig. Figure 8 shows the retaining ring 12 according to the training as per Fig. 2. It has a square cross-section and flat outer surfaces. Such a retaining ring 12 secures the magnets 5 in the axial direction, since, as Fig. Figure 2 shows that its flat inner surface 22 rests against the end face 8, 21 of the magnets 5 of the magnet row 5a. The inner surface 15 of the retaining ring 12 lies at least approximately flush with the inner surface 17 of the magnets 5 ( Fig. 5) This embodiment is characterized by its simple and cost-effective manufacture. No special machining and / or shaping of the retaining ring 12 is required.

[0076] The retaining ring 12 according to Fig. 8b has an education, as shown by the Fig. 3 and Fig. 4 is described. The annular projection 16 extends axially from the inner side 22, as shown by the Fig. 3 and Fig. 4 has been described, forming a radial positive fit for magnets 5 of the magnet series 5a.

[0077] The retaining ring 12 according to Fig. 8c consists of individual ring sections 12a, which are joined together to form the retaining ring 12. Small, radially extending gaps 28 are located between the ring sections 12a. The ring sections 12a are advantageously identical. In this example, the retaining ring 12 is formed by ten ring sections 12a. Depending on the diameter of the retaining ring 12, the number of ring sections 12a may vary.

[0078] The ring sections 12a are designed with the same cross-sectional shape as the retaining ring 12 according to Fig. 8a. The ring sections 12a accordingly have smooth outer surfaces. The radial gaps 28 are very small in relation to the circumferential width of the ring sections 12a, so that the magnets 5 of the magnet series 5a are reliably axially secured in the installed position.

[0079] The retaining ring 12 can also be used during training accordingly. Fig. 8b consist of individual ring sections 12a. In this case, the ring sections 12a have the radially inner projection 16, which extends over the circumferential length of the ring sections 12a. With such a design, after their attachment by friction stir welding, the ring sections 12a also position the magnets 5 of the magnet series 5a in the radial direction 2, as can be seen from the Fig. 3 and Fig. 4 has been described for a closed retaining ring.

[0080] The retaining ring 12 according to Fig. 9a is designed to ensure alignment of the magnets 5 in both radial and circumferential directions. Radial alignment is achieved by the annular projection 16, which extends as described around the circumference of the retaining ring 12 on its inner surface 15. In this respect, the retaining ring 12 has a corresponding design. Fig. 8b.

[0081] In addition to the projection 16, the annular inner surface 22 of the retaining ring 12 is provided with raised sections 29, which are distributed around the circumference of the retaining ring 12, preferably evenly spaced. The raised sections 29 extend from the cylindrical outer surface 13 towards the projection 16. The raised sections 29 terminate at a radial distance from the projection 16.

[0082] The raised sections 29, viewed in the axial direction of the retaining ring 12, are preferably triangular in shape. The circumferential width of the raised sections 29 decreases continuously from the outer surface 13. The raised sections 29 each terminate in a point 30.

[0083] The triangular protrusions 29 are designed such that the magnets 5 with their narrow sides 25, 26 lie against the mutually facing side surfaces 34 of adjacent protrusions 29 ( Fig. 9a). This also aligns the magnets 5 in the circumferential direction relative to the retaining ring 12.

[0084] The raised sections 29 do not need to be very high to provide circumferential security. A triangular shape for the raised sections 29 is not necessary. Circumferential security can also be achieved through other shapes of the raised sections 29, for example, by diagonally arranged, straight ribs, and the like.

[0085] Fig. Figure 9b shows a retaining ring which, according to the previous embodiment, is provided with the circumferential annular projection 16. On the end face 22 are recesses 31, which are arranged one behind the other at close intervals in the circumferential direction of the retaining ring 12. The recesses 31 are separated from one another by separating pieces 32, which, in axial view, have an exemplary triangular shape. The separating pieces 32 taper continuously towards the projection 16 and terminate in a point in the region of the projection. Thus, viewed axially, the separating pieces 32 have the same shape as the raised sections 29 of the embodiment according to Fig. 9a. The separating pieces 32 also serve to align the magnets 5 in the circumferential direction within the housing 1.

[0086] The magnets 5 engage in the recesses 31 and lie with their narrow sides 25, 26 against the mutually facing side walls 35 of adjacent separating pieces 32, thereby achieving circumferential locking.

[0087] The described friction stir welding process allows the magnets 5 to be reliably and easily attached to the housing 1. The application of the friction stir welding process reduces electromagnetic excitation in the magnetic circuit due to minimal excitation of the magnets 5 and eliminates the need for an adhesive gap. The costs associated with the joining process can be kept low. The magnets 5 are readily recyclable, particularly because no adhesive is required to attach them to the housing 1. Friction stir welding is environmentally friendly and energy-efficient.

[0088] The Fig. 12 and Fig.Figure 13 shows the possibility of using one or more magnetic rings 50 instead of the individual magnets 5. A retaining ring 12, which has an axial projection 16, is attached to one end face 21. It rests against the inner surface 17 of the magnetic ring 50 over its circumference. The magnetic ring 50 is fastened in the housing 1 as described.

Claims

[1] Rotor for an electric motor, comprising a housing (1) on the inside of which at least one magnet (5, 50) is held, which is held in the housing (1) by at least one locking element (12). characterized by , that the locking element (12) secures the magnet (5, 50) at least axially in the housing (20) and is connected to the housing (1) by at least one friction stir weld (20). [2] Rotor according to claim 1, characterized by , that the locking element (12) is designed as a ring. [3] Rotor according to claim 1 or 2, characterized by , that the housing (1) encloses a receiving space (33) with a rim (10) into which the locking element (12) is inserted. [4] Rotor according to claim 3, characterized by , that the locking element (12) rests with an outer side (13) against an inner side (14) of the housing edge (10). [5] Rotor according to claim 4, characterized by, that the friction stir weld (20) extends at least over part of the thickness of the locking element (12) and the housing edge (10). [6] Rotor according to any one of claims 1 to 5, characterized by , that the friction stir weld (20) extends at least over part of the thickness of the locking element (12) and the housing edge (10). [7] Rotor according to any one of claims 1 to 6, characterized by , that the friction stir weld (20) extends over the circumference of the housing edge (10). [8] Rotor according to any one of claims 1 to 6, characterized by , that the friction stir weld (20) is formed by individual weld sections spaced apart from each other around the circumference of the housing edge (10). [9] Rotor according to any one of claims 1 to 8, characterized by , that the locking element (12) is in contact with the front face (21) of at least one magnet (5, 50). [10] Rotor according to any one of claims 1 to 9, characterized by, that the end faces (18, 19) of the housing edge (10) and of the locking element (12) lie in a common radial plane of the rotor. [11] Rotor according to any one of claims 1 to 10, characterized by , that the magnet (5, 50) is secured axially between the locking element (12) and an axial stop (6) of the housing (1). [12] Rotor according to any one of claims 1 to 11, characterized by , that the rotor has several magnets (5) which are arranged in at least one row (5a, 5b) in the circumferential direction of the housing (1). [13] Rotor according to any one of claims 1 to 11, characterized by , that the rotor has at least one magnetic ring (50) which extends over the circumference of the housing (1). [14] Rotor according to any one of claims 1 to 13, characterized by , that the magnet (5, 50) is secured in the radial direction by the locking element (12). [15] Rotor according to claim 14, characterized by, that the locking element (12) has at least one alignment part (16) which rests against the side (17) of the magnet (5, 50) facing away from the housing (1). [16] Rotor according to claim 15, characterized by , that the alignment part (16) is designed as a ring-shaped projection. [17] Rotor according to any one of claims 1 to 16, characterized by , that the magnets (5) are aligned in the circumferential direction of the housing (1) by the locking element (12). [18] Rotor according to claim 17, characterized by , that the locking element (12) has at least one positive locking element (29, 32) on its end face (22) facing the magnets (5, 50), against which the magnet (5) rests in the circumferential direction of the housing (1) and which prevents or at least limits a rotation of the magnet (5) in the circumferential direction of the housing (1). [19] Rotor according to any one of claims 1 to 18, characterized by, that the magnet (5) has at least one receptacle (23, 27) on its end face for a part of the material softened by friction stir welding. [20] Electric motor, in particular EC external rotor motor, with a stator and a rotor according to any one of claims 1 to 19. [21] Method for manufacturing a rotor according to one of claims 1 to 19, in which at least one magnet (5, 50) is inserted into a housing (1) of the rotor, which is axially secured by at least one locking element (12) which is firmly connected to the housing (1) by a friction stir welding process.

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