Rotor with slip ring device, method for producing a rotor with a slip ring device, and electric machine with a rotor
Patent Information
- Application Number
- EP2023741323
- Authority / Receiving Office
- EP · EP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2022-07-14
- Filing Date
- 2023-07-10
- Publication Date
- 2025-05-21
AI Technical Summary
The existing rotor designs with slip ring devices for electrical machines do not provide a fluid-tight seal between the rotor and the sliding contacts, which is problematic when the rotor is cooled with oil, as it allows oil to seep between the sliding contacts and slip rings.
A rotor design with a built-in slip ring device that runs through a cylindrical hollow shaft section, allowing for a continuous outer lateral surface for bearing arrangement and a flange section with busbar openings to guide the busbars out, ensuring a fluid-tight seal and easy assembly.
This design effectively prevents coolant, such as oil, from reaching the slip rings while allowing for simple and cost-effective installation of the slip ring device, reducing manufacturing costs and maintaining structural rigidity with metallic materials.
Smart Images
Figure 1.1
Abstract
Description
[0001] Description
[0002] Rotor with slip ring device, method for producing a rotor with a grinding straightening device and electrical machine with a rotor
[0003] The invention relates to a rotor for an electrical machine, wherein the rotor has a built-up rotor shaft with a hollow shaft support and a shaft stub arranged at the end, wherein a slip ring device is guided through a shaft section of the shaft stub. The invention also relates to a method for producing the rotor according to the invention. Furthermore, the invention relates to a separately excited electrical machine with the rotor according to the invention.
[0004] A rotor with a slip ring device is known, for example, from EP 2 816 711 B1, in which the slip ring device is plugged onto a rotor shaft from the outside. A bearing is arranged on the slip ring device in an area of the overmolded electrical conductors. The problem here is that the bearing arrangement in the area of the slip ring arrangement does not provide a fluid-tight seal between the rotor and the sliding contacts mounted on the slip rings. This is particularly disadvantageous when the rotor is oil-cooled, since it is important to prevent the oil from the rotor cooling system from getting between the sliding contacts and the slip rings.
[0005] It is an object of the invention to provide a rotor for a separately excited electrical machine in which the slip ring can be arranged in a simple and inexpensive manner and enables a fluid-tight separation between an active part of the rotor and a current-supply section of the rotor.
[0006] This object is achieved by the subject matter of the independent patent claims. Preferred developments of the invention are the subject matter of the dependent patent claims, the following description, and the drawings, wherein each feature can represent an aspect of the invention both individually and in combination, unless explicitly stated otherwise in the description.
[0007] In a first aspect, the invention relates to a rotor for a separately excited electrical machine, comprising a built-up rotor shaft with a cylindrical hollow shaft body, at the respective axial end of which a shaft stub is arranged, wherein the respective shaft stub has a flange section and a shaft section, wherein the shaft section has an outer circumferential surface, a slip ring device extending through the shaft section, which has at least one annular first slip ring which projects beyond a distal end of the shaft section in the axial direction of the rotor, and a first busbar connected to the first slip ring and extending through the shaft section, wherein one end of the first busbar is guided through a first busbar opening formed in the flange section and is thus guided out of an interior of the hollow shaft body.
[0008] In other words, according to the first aspect of the invention, a rotor is provided for a separately excited electric machine. The electric machine is preferably configured and / or designed to be arranged in a motor vehicle. The electric machine is preferably located in a drive train of the motor vehicle in order to be able to drive the motor vehicle at least partially electrically.
[0009] The rotor has an assembled rotor shaft. The assembled rotor shaft comprises a cylindrical hollow shaft body, on which a rotor laminated core is usually arranged. The rotor laminated core, together with a rotor winding arranged thereon, can also be referred to as the active part of the rotor. A shaft stub is arranged at the respective axial end of the hollow shaft body. The respective shaft stub comprises a flange section and a shaft section. The flange section is preferably designed and / or constructed to form a connection with the hollow shaft body. The shaft section is preferably designed and / or constructed to mount the rotor via at least one bearing device such that the rotor can rotate about a rotor axis of the rotor. For this purpose, the shaft section is provided with an outer circumferential surface. The outer circumferential surface is preferably in the circumferential direction of the rotor orof the shaft section is continuous, i.e. uninterrupted.
[0010] Furthermore, the rotor comprises a slip ring device that runs through the shaft section or through an interior of the shaft section. The slip ring device comprises at least one annular first slip ring that projects beyond a distal end of the shaft section in the axial direction of the rotor. This section of the slip ring device that projects beyond the distal end of the shaft section can also be referred to as the energization section. The distal end of the shaft section is formed on a side of the shaft section facing away from the hollow shaft body. A first busbar that runs through the shaft section is electrically connected to the first slip ring. A distal end of the first busbar is guided through a first busbar opening formed in the flange section. The distal end of the first busbar is thus guided out of an interior of the hollow shaft body.Consequently, the end of the first busbar can be electrically connected to a rotor winding of the separately excited rotor. The first slip ring and / or the first busbar are each formed from an electrically conductive material. The electrically conductive material preferably comprises copper and / or is formed from copper. In particular, the electrically conductive material is a copper alloy, which particularly advantageously comprises at least partially bronze.
[0011] Because the slip ring device extends through the interior of the shaft section, the shaft section can have a continuous outer surface in the circumferential direction of the rotor, on which a bearing device for rotatably supporting the rotor can be arranged. Thus, in this region of the shaft section, a fluid-tight or coolant-tight seal can be easily created between the bearing device and the bearing seat, preventing coolant, in particular oil, from the rotor from entering the area of the first slip ring.
[0012] In addition, the slip ring device can be arranged easily and inexpensively in the rotor thanks to the internal slip ring device in the shaft section.
[0013] An advantageous development of the invention lies in the fact that the flange section, the shaft section and / or the hollow shaft body are made of the same material. It is therefore conceivable that the flange section and the shaft section are made of the same material, with the hollow shaft body comprising a different material than the shaft section. However, it is also conceivable that the shaft section and the hollow shaft body are made of the same material, with the flange section comprising a different material. However, it is preferably provided that the flange section, the shaft section and the hollow shaft body are made of the same material. This has the advantage that the three components can be easily connected to one another, provided they are not at least partially formed integrally with one another.Furthermore, the risk of contact corrosion in the three components can be reduced if they are preferably made of the same metallic material.
[0014] Preferably, the shaft section and the shaft flange are formed as a single piece. This single-piece design means that the shaft section and the shaft flange are manufactured and connected to one another in a single manufacturing process. This can be done, for example, by an additive process, a casting process, and / or a milling process.
[0015] In a preferred embodiment of the invention, it is provided that the flange section, the shaft section and / or the hollow shaft body are formed from a metal and / or comprise a metallic material. This has the advantage that the rotor can have the required structural rigidity for the planned service life of the rotor using an inexpensive material. In this way, the manufacturing costs of the rotor can be reduced. According to an advantageous development of the invention, it is provided that at an axial end of the hollow shaft body, one of the shaft stubs is formed integrally with the hollow shaft body. Accordingly, it can be provided that the shaft stub is already formed integrally with the hollow shaft body.In other words, the hollow shaft body is provided with an opening at one distal end, while at another distal end of the hollow shaft body, the shaft stub is formed directly, i.e., immediately, with the hollow shaft body in a single manufacturing process. This has the advantage of reducing the number of components. This, in turn, can have a beneficial effect on the manufacturing process, thereby reducing manufacturing costs.
[0016] In a preferred embodiment of the invention, it is provided that the shaft stub is connected to the hollow shaft body at one axial end of the hollow shaft body in a materially bonded, positively bonded and / or non-positively bonded manner. The materially bonded connection can preferably be an adhesive connection and / or a welded connection. The positively bonded connection can preferably be a connection in which the flange of the shaft stub engages with the hollow shaft body at least at one point. This can preferably be a guide structure comprising a tongue and groove connection. The non-positively bonded connection can preferably be a screw and / or riveted connection. In this case, it can preferably be provided that the flange is screwed onto the hollow shaft body.
[0017] An advantageous embodiment of the invention provides that the slip ring device has an annular second slip ring which is different from the first slip ring and spaced from the first slip ring in the axial direction of the rotor, and a second busbar connected to the second slip ring and extending through the shaft section, wherein one end of the second busbar is guided through a second busbar opening formed in the flange section and is thus led out of the interior of the hollow shaft body. In other words, it is provided that the slip ring device has two spaced-apart and separate electrically conductive slip rings, wherein each slip ring is connected to at least one electrically conductive busbar. The first slip ring has at least the first busbar and the second slip ring has at least the second busbar.Both the end of the first busbar and the end of the second busbar are guided through a corresponding busbar opening in the flange section of the stub shaft. The respective end of the busbar is designed and configured to be electrically connected to the rotor winding of the rotor.
[0018] It is conceivable that the outer diameter of the annular first slip ring is equal to the outer diameter of the annular second slip ring. This has the advantage that the sliding contacts, or carbon brushes, acting on the first slip ring and the second slip ring can be arranged at the same height. However, the disadvantage is that arranging the two slip rings next to each other and guiding the two busbars in the slip ring device is somewhat more complex, particularly during the manufacture of the slip ring device, since the first busbar and the second busbar cannot be guided at the same height relative to the radial direction of the busbars.
[0019] Alternatively, a preferred development of the invention provides that an outer diameter of the annular first slip ring is smaller than an inner diameter of the annular second slip ring. If, in this context, the respective busbar extends in the axial direction of the respective slip ring, the first slip ring can be guided through the second slip ring, and the first busbar and the second busbar run parallel to one another at least in sections and / or offset from one another in the circumferential direction. Thus, the slip rings can be arranged in a simple manner. This applies in particular to an overmolding process.
[0020] An advantageous embodiment of the invention is that the first slip ring and / or the second slip ring are arranged in an electrically insulating slip ring carrier. It goes without saying that at least one outer circumferential surface of the first slip ring and the second slip ring is exposed so that they can come into electrically conductive contact with the sliding contacts, which can also be referred to as carbon brushes. It is provided that not only the slip rings, but also the first busbar and / or the second busbar are arranged in the slip ring carrier. It is preferably provided that, with the exception of the respective distal end section, these are completely surrounded by the insulating slip ring carrier or embedded in it. The slip ring device can thus be easily prefabricated and inserted into the shaft section.The possibility of prefabrication can reduce production costs.
[0021] It is particularly advantageous for the slip ring carrier to be sealed in a media-tight manner in the area of the respective busbar opening. This prevents coolant from penetrating the interior of the hollow shaft body through the busbar opening. Likewise, when the hollow shaft body is cooled from the inside, a seal can be achieved that prevents the coolant from penetrating to the outside through the busbar openings.
[0022] In principle, the slip ring device can be arranged in the shaft section such that it is connected to the shaft section in a rotationally fixed manner. A preferred embodiment of the invention provides that the slip ring device is arranged in the shaft section in a form-fitting, material-fitting and / or force-fitting manner. The form-fitting arrangement can provide that the shaft section has a projection on a side facing inwards in the radial direction and the slip ring device has a recess corresponding to the projection on an outer side facing outwards in the radial direction, such that when the slip ring device is inserted, the projection engages in the recess in the axial direction of the shaft section and forms a form-fitting connection with the shaft section. The material-fitting connection is preferably an adhesive connection. The force-fitting connection can preferably be a screw and / or rivet connection.An advantageous development of the invention lies in the fact that a bearing seat is formed on an outer circumferential surface of the shaft section. In the area of the bearing seat, the outer circumferential surface of the shaft section is completely closed in the circumferential direction. In addition, a step is formed in the area of the bearing seat with respect to the radial direction of the shaft section, which step serves as a stop for the bearing seat in the axial direction of the rotor. It is particularly advantageous that a bearing device is arranged on the bearing seat so that the rotor is rotatably mounted. The design of the bearing seat and the arrangement of the bearing device prevent a coolant of the rotor, in particular an oil, from flowing in the area of the bearing seat towards the slip rings and coming into contact with them.
[0023] In a second aspect, the invention relates to a method for producing the rotor according to the invention, wherein the slip ring device is inserted with the annular first slip ring first over a flange side of the shaft stub into the shaft section, so that the first slip ring is led out beyond the distal end of the shaft section, and the end of the first busbar is led through the first busbar opening of the flange section.
[0024] The end of the first busbar is therefore formed on a side of the busbar facing away from the slip ring. The end of the first busbar is preferably deflected such that it is directed in the direction of the first slip ring or is aligned parallel to the longitudinal direction of the first slip ring. In this way, the slip ring device can be inserted into the shaft section, preferably coaxially to the shaft section, via a translational movement, wherein the first slip ring projects beyond the distal end of the shaft section and the end of the first busbar is guided through the busbar opening in the flange section. The slip ring device can thus be arranged in the rotor in a simple and cost-effective manner. Due to the fact that the slip ring device is designed to be internal, a bearing device for rotatably supporting the rotor can be arranged on the shaft section.An outer surface can be formed continuously in the area of the bearing device so that it can be prevented that the cooling medium of the rotor in the area of the rotor bearing reaches the direction of the first slip ring.
[0025] In a preferred embodiment of the invention, the shaft end and the hollow shaft body are connected to each other in a materially bonded, positively connected, and / or non-positively connected manner after the slip ring device has been arranged in the shaft end. The materially bonded connection is preferably an adhesive connection or a welded connection. The positive connection is preferably a tongue-and-groove connection. The non-positive connection is preferably a screw and / or riveted connection.
[0026] An advantageous embodiment of the invention provides that the slip ring device is arranged in the shaft section in a materially bonded, non-positively bonded, and / or positively bonded manner. The positively bonded arrangement can provide that the shaft section has a projection on a side facing inward in the radial direction, and the slip ring device has a recess corresponding to the projection on an outer side facing outward in the radial direction, such that the projection engages in the recess when the slip ring device is inserted in the axial direction of the shaft section and forms a positive connection with the shaft section. The materially bonded connection is preferably an adhesive connection. The non-positive connection can preferably be a screw and / or rivet connection.
[0027] The slip ring device, comprising the first slip ring and the first busbar, is preferably arranged in the slip ring carrier by overmolding. The first slip ring, the first busbar, the second slip ring, and the second busbar are preferably arranged in the slip ring carrier by overmolding. In this way, a slip ring device is provided that can be prefabricated and easily arranged in the shaft stub. Thus, manufacturing costs can be reduced. In a third aspect, the invention relates to a separately excited electrical machine with the rotor according to the invention.
[0028] The electric machine is preferably a component of a traction drive in order to drive a motor vehicle at least partially, preferably completely, electrically.
[0029] It should be noted that all features described above and below with respect to one aspect of the present invention apply equally to any other aspect of the present invention. In particular, all features of the rotor can also be features of the method and / or the electric machine. This also applies vice versa.
[0030] Further features and advantages of the present invention emerge from the dependent claims and the following exemplary embodiments. The exemplary embodiments are not limiting, but rather are to be understood as examples. They are intended to enable the skilled person to implement the invention. The applicant reserves the right to make individual and / or several of the features disclosed in the exemplary embodiments the subject of patent claims or to incorporate such features into existing patent claims. The exemplary embodiments are explained in more detail with reference to drawings.
[0031] In these show:
[0032] Fig. 1 shows a section of a three-dimensional view of a rotor in the area of a shaft stub with a slip ring device;
[0033] Fig. 2 is an exploded view of the rotor;
[0034] Fig. 3 a sectional view through the shaft stub and the slip ring device.
[0035] Fig. 1 shows a section of a three-dimensional view of a rotor RO in the area of a shaft stub WS with a slip ring device SRV. The rotor RO has an assembled rotor shaft RW. The assembled rotor shaft RW comprises a cylindrical hollow shaft body HWK, on which a rotor laminated core RBP is arranged in a rotationally fixed manner. The shaft stub WS is arranged at the respective axial end of the hollow shaft body HWK. The respective shaft stub WS comprises a flange section FA and a shaft section WA. The flange section FA is connected in a rotationally fixed manner to the hollow shaft body HWK. The shaft section WA is set up and / or designed to mount the rotor RO via at least one bearing device LER such that the rotor can rotate about a rotor axis RA of the rotor RO. For this purpose, the shaft section WA is provided with an outer circumferential surface AM. The outer circumferential surface AM is in the circumferential direction of the rotor RO orof the shaft section WA is continuous, i.e. uninterrupted or continuously annular.
[0036] The slip ring device SRV runs through the shaft section WA and comprises an annular first slip ring ESR and an annular second slip ring ZSR. Both the first slip ring ESR and the second slip ring ZSR project at least partially beyond a distal end DE of the shaft section WA relative to the axial direction of the rotor RO. The distal end DE of the shaft section WA is formed on a side of the shaft section WA facing away from the hollow shaft body HWK. A first busbar ESS running through the shaft section WA is electrically connected to the first slip ring ESR. A second busbar ZSS is also electrically contacted with the second slip ring ZSR. A distal end of the first busbar ESS is guided through a first busbar opening ESO formed in the flange section FA of the shaft stub WS.Likewise, a distal end of the second busbar ZSS is guided through a second busbar opening ZSO formed in the flange section FA of the shaft stub WS. Thus, the distal end of the first busbar ESO and the distal end of the second busbar ZSS are guided out of an interior of the hollow shaft body HWK. Consequently, the end of the first busbar ESS and the end of the second busbar ZSS can be electrically connected to a rotor winding (not shown) of the separately excited rotor RO. The first slip ring ESR, the second slip ring ZSR, the first busbar ESS and the second busbar ZSS are each formed from an electrically conductive material. The electrically conductive material preferably comprises copper and / or is formed from copper. It is conceivable that the first busbar ESS is arranged with a material fit to the first slip ring ESR and / or the second busbar ZSS is arranged with a material fit to the second slip ring ZSR.The integral connection is preferably a soldered or welded joint. However, it is also conceivable for the first busbar ESS and the first slip ring ESR and / or the second busbar ZSS and the second slip ring ZSR to be formed integrally with one another.
[0037] Because the slip ring device SRV extends through the interior of the shaft section WA, the shaft section WA in the present exemplary embodiment has an outer circumferential surface AM in the region of a bearing seat LS, which extends continuously in the circumferential direction of the rotor RO. A bearing device LER for rotatably supporting the rotor RO can be arranged on said outer surface. Thus, in this region of the shaft section WA, a fluid-tight or coolant-tight seal can be easily achieved in the region of the bearing seat LS, preventing coolant, in particular oil, from the rotor RO from entering the area of the slip rings ESR, ZSR.
[0038] It can also be seen that the first slip ring ESR, the first busbar ESS, the second slip ring ZSR and the second busbar ZSS are arranged in a slip ring carrier SRT by overmolding. In other words, the first slip ring ESR and the first busbar ESS, the second slip ring ZSR and the second busbar ZSS are arranged in the slip ring carrier or held by it. The first slip ring ESR and the second slip ring are galvanically isolated from one another in the slip ring carrier SRT and arranged at a distance from one another in the axial direction of the rotor RO. An outer circumferential surface of the first slip ring ESR and an outer circumferential surface of the second slip ring ZSR are exposed so that they can come into electrically conductive contact with the sliding contacts or carbon brushes (not shown).By arranging the slip rings ESR and ZSR in the slip ring carrier SRT, a slip ring device SRV is provided that can be prefabricated and easily installed in the shaft stub WS. This reduces manufacturing costs.
[0039] As can be seen from Fig. 1 and Fig. 2, an outer diameter of the annular first slip ring ESR is smaller than an inner diameter of the annular second slip ring ZSR. If, in this context, the respective busbar ESS, ZSS connected to the slip ring ESR, ZSR extends in the axial direction of the respective slip ring ESR, ZSR, the first slip ring ESR can be guided through the second slip ring ZSR and the first busbar ESS and the second busbar ZSS run parallel to one another at least in sections and / or offset from one another in the circumferential direction. Thus, the first slip ring ESR and the second slip ring ZSR can be arranged relative to one another in a simple manner before being encapsulated in a plastic material to form the slip ring carrier SRT.
[0040] Fig. 3 shows a sectional view through the shaft end WS and the slip ring device SRV. The end of the second busbar ZSS is formed on a side of the second busbar ZSS facing away from the second slip ring ZSR, with the end of the second busbar ZSS being deflected such that it is directed toward the second slip ring ZSR or parallel to the longitudinal direction of the second slip ring ZSR. The first busbar ESS is formed in the same way.Thus, the slip ring device SRV can preferably be inserted into the shaft section WA coaxially to the shaft section WA via a translational movement, wherein the first slip ring ESR and the second slip ring ZSR project beyond the distal end DE of the shaft section WA and the end of the first busbar ESS is guided through the first busbar opening ESO in the flange section FA and the end of the second busbar ZSS is guided through the second busbar opening ZSO. The slip ring device SRV can thus be arranged in the rotor RO in a simple and cost-effective manner. Due to the fact that the slip ring device SRV is designed to be internal, the bearing device LER arranged on the shaft section WA for the rotatable mounting of the rotor RO can enable a fluid-tight seal to the shaft section WA, so that in this area a coolant, in particular an oil, from the area of the rotor RO does not reach the slip rings ESR, ZSR.
[0041] The slip ring carrier SRT forms a media-tight seal in the area of the first busbar opening ESO and / or the second busbar opening ZSO. This prevents coolant from penetrating the hollow shaft body HWK via the first busbar opening ESO and / or the second busbar opening ZSO.
Claims
Patent claims 1. Rotor (RO) for a separately excited electrical machine, comprising a built-up rotor shaft (RW) with a cylindrical hollow shaft body (HWK), at the respective axial end of which a shaft stub (WS) is arranged, wherein the respective shaft stub (WS) has a flange section (FA) and a shaft section (WA) which comprises an outer circumferential surface (AM), a slip ring device (SRV) extending through the shaft section (WA), which has at least one annular first slip ring (ESR) which projects beyond a distal end (DE) of the shaft section (WA) in the axial direction of the rotor (RO), and a first busbar (ESS) connected to the first slip ring (ESR) and extending through the shaft section (WA), wherein one end of the first busbar (ESS) is guided through a first busbar opening (ESO) formed in the flange section (FA) and is thus guided out of an interior of the hollow shaft body (HWK).
2. Rotor according to claim 1, characterized in that the flange section (FA), the shaft section (WA) and / or the hollow shaft body (HWK) are made of the same material.
3. Rotor according to one of the preceding claims, characterized in that the flange section (FA), the shaft section (WA) and / or the hollow shaft body (HWK) are formed from a metal and / or comprise a metallic material.
4. Rotor according to one of the preceding claims, characterized in that at an axial end of the hollow shaft body (HWK) one of the shaft stubs (WS) is formed integrally with the hollow shaft body (HWK).
5. Rotor according to one of the preceding claims, characterized in that at one axial end of the hollow shaft body (HWK) the shaft stub (WS) is connected to the hollow shaft body (HWK) in a material-locking, form-locking and / or force-locking manner.
6. Rotor according to one of the preceding claims, characterized in that the slip ring device (SRV) has an annular second slip ring (ZSR) which is different from the first slip ring (ESR) and spaced apart from the first slip ring (ESR) in the axial direction of the rotor (RO), and a second busbar (ZSS) which is connected to the second slip ring (ZSR) and runs through the shaft section (WA), one end of the second busbar (ZSS) being guided through a second busbar opening (ZSO) formed in the flange section (FA) and thus being guided out of the interior of the hollow shaft body (HWK).
7. Rotor according to claim 6, characterized in that the outer diameter of the annular first slip ring (ESR) is smaller than an inner diameter of the annular second slip ring (ZSR).
8. Rotor according to one of claims 6 or 7, characterized in that the first slip ring (ESR) and / or the second slip ring (ZSR) are arranged in an electrically insulating slip ring carrier (SRT).
9. Rotor according to claim 8, characterized in that the slip ring carrier (SRT) is sealed in a media-tight manner with the respective busbar opening (ESO, ZSO) in the region of the latter.
10. Rotor according to one of the preceding claims, characterized in that a bearing seat (LS) is formed on an outer circumferential surface (AM) of the shaft section (WA).
11. Rotor according to one of the preceding claims, characterized in that the slip ring device (SRV) is arranged in the shaft section (WA) in a form-fitting, material-fitting and / or force-fitting manner.
12. Method for producing a rotor (RO) according to one of the preceding claims, wherein the slip ring device (SRV) with the annular first slip ring (ESR) first is inserted into the shaft section (WA) via a flange side of the shaft stub (WS) so that the first slip ring (ESR) is guided beyond the distal end (DE) of the shaft section (WA), and the end of the first busbar (ESS) is guided through the first busbar opening (ESO) of the flange section (FA).
13. Method according to claim 12, characterized in that the shaft stub (WS) and the hollow shaft body (HWK) are connected to one another in a materially bonded, positively bonded and / or non-positively bonded manner after the arrangement of the slip ring device (SRV) in the shaft stub (WS).
14. Method according to claim 12 or 13, characterized in that the slip ring device (SRV) is arranged in the shaft section (WA) in a materially bonded, non-positively bonded and / or form-fitting manner.
15. Method according to one of claims 12 to 14, characterized in that the first slip ring (ESR), the first busbar (ESS), the second slip ring (ZSR) and the second busbar (ZSS) are arranged in the slip ring carrier (SRT) by overmolding.
16. Electrical machine with a rotor (RO) according to one of claims 1 to 11.