Separately excited rotor having a doubly sheathed contact wire, method for the production thereof, electric machine having such a rotor, and motor vehicle therewith

Abstract

The invention relates to a separately excited rotor (1) in which one end of a rotor winding (4) is connected, as a contact wire (7), to a corresponding terminal contact (6) of an end disc (5). The terminal contact (6) is arranged in a receiving space (10) which is filled with an electrically insulating elastic material. The surrounding areas are encapsulated with an electrically insulating potting compound that is more rigid in comparison thereto. The invention also relates to a method (18) for producing such a rotor (1), to an electric machine (17) having such a rotor (1), and to a motor vehicle (16) having such an electric machine (17).

Description

[0001] 24-3542

[0002] 1

[0003] Externally excited rotor with double-sheathed contact wire, method for its manufacture, electric machine with such a rotor and motor vehicle therewith

[0004] The present invention relates to a separately excited rotor and a method for its manufacture. The invention also relates to an electric machine with such a rotor and a motor vehicle with such an electric machine.

[0005] Electrical machines can be used effectively in a wide variety of applications. Increasingly stringent requirements are being placed on them, for example, regarding efficiency, weight, robustness, and reliability, while simultaneously striving for the simplest possible design and lowest possible cost. One challenge, for instance, can be the reliable and precise arrangement and electrical insulation of components. The production and arrangement of prefabricated, dimensionally stable components for electrical insulation and / or for fixing other components can be complex and prone to errors due to their intricate geometries. The application of liquid insulating or potting materials can, in principle, address this problem.However, low-viscosity materials may flow off undesirably and uncontrollably, high-viscosity materials may not penetrate relatively small gaps, and solidifying materials may break or crack during hardening and / or later operation.

[0006] One approach to improving production efficiency is described by the

[0007] WO 2021 / 229807 A1 describes a squirrel-cage rotor with a laminate of multiple steel plates as the rotor core and a conductor in each of multiple slots.

[0008] 18.02.202524-3542

[0009] 2

[0010] Slots are arranged circumferentially around a rotational axis of the rotor core. An insulating layer is formed in the slots by applying an insulating paint. The insulating material contains a modified silicone resin, inorganic particles, and a thinning agent.

[0011] DE 102023120815 A1 describes a rotor for a reluctance machine with a rotor body having cavities defined by the inner surfaces of the rotor body. A filler is arranged in the cavities and is covalently bonded to the inner surfaces of the rotor body by an adhesive coating. The adhesive coating is formed by applying a precursor composition to the inner surfaces and then subjecting the precursor composition to a plasma on the inner surfaces of the rotor body. The precursor composition comprises an organofunctional silane or a hydrolysate thereof, while the adhesive coating has a composite structure containing a continuous matrix component and a discontinuous organic component.

[0012] However, these existing approaches cannot solve all the problems observed in practice. Therefore, further improvements are needed.

[0013] The object of the present invention is to provide a particularly robust and reliable electrical machine in a simple manner.

[0014] This problem is solved by the subject matter of the main claim and the dependent claims or independent claims. Further possible embodiments of the invention are disclosed in the subclaims, the description, and the figures. Features, advantages, and possible embodiments set forth in the description for one of the subject matter of the independent claims are to be regarded, at least analogously, as features, advantages, and possible embodiments of the respective subject matter of the other independent claims, as well as of any possible combination of the subject matter of the independent claims, optionally in conjunction with one or more of the dependent claims.

[0015] The separately excited rotor according to the invention, i.e., designed for separate excitation, is intended for an electric machine, in particular as an internal rotor. The rotor according to the invention comprises at least one winding carrier and at least

[0016] 18.02.202524-3542

[0017] 3

[0018] A winding wire is wound around the winding carrier to form a rotor winding and thus ultimately one or more poles of the rotor. Additionally, the rotor according to the invention comprises an end disk or star disk positioned perpendicular to the intended axis of rotation of the rotor, which at least partially covers a radially inner part of the winding carrier in an axial end region of the rotor. This radially inner part can be a portion or region located radially inside the winding heads formed by the rotor winding. The end disk surrounds a rotor shaft for the rotor or rotors in an annular manner and has an electrical connection contact on its axially outer end face, radially inside the rotor winding or a main part, i.e., a winding head of the rotor winding.The end plate can, for example, function as a switching ring or include a switching ring to which various winding wires of the rotor can be electrically connected. The electrical connection contact of the end plate can be electrically connected at its other end, for example, to a slip ring module, a brush holder, an adjacent pole, an adjacent rotor winding, or an adjacent winding wire of the rotor.

[0019] According to the invention, one end of the winding wire is guided radially inwards from the rotor winding or from a main part of the rotor winding to the connection contact and electrically connected to it there. The end disk, including the connection contact (i.e., the electrical connection point between the rotor winding and the end disk), is at least partially covered by a cover element that is parallel to the end disk and axially outside of it.

[0020] According to the invention, the end plate and the cover element together form walls of a receiving space that surround the connection contact and the electrically connected end of the winding wire, except for a single passage through which the winding wire is led from the receiving space to the rotor winding or its main part, at least substantially completely or except for a side enclosed by the rotor shaft. The passage can, in particular, be arranged radially on the outside or run at least partially or substantially tangentially in a radially outer region of the receiving space. Accordingly, the winding wire can thus pass radially, tangentially, or obliquely through the

[0021] 18.02.202524-3542

[0022] 4

[0023] The process must be guided, i.e., carried out in a guided manner. The receiving space is narrower in the circumferential direction around the rotor shaft than a pole of the rotor. In other words, the receiving space can be specifically dimensioned to receive the connection contact and the corresponding end of the winding wire without, for example, encompassing a significantly or several times larger section in the circumferential direction. For example, the receiving space can be at most five times or at most twice as wide in the circumferential direction as the connection contact and the end of the winding wire connected to it combined.

[0024] According to the invention, the receiving chamber is filled with an electrically insulating elastic material, for example, by casting or injection molding. Surrounding areas of the rotor—at least those located axially on the inner side of the cover element—are encased or potted with a comparatively firmer, i.e., stiffer and less elastic, electrically insulating potting material. The elastic material can, in particular, be a silicone or a polyorganosiloxane.

[0025] The end plate and / or the cover element can, in particular, form walls or have wall sections that extend axially between the end plate and the cover element. For example, some of these walls or wall sections can extend outwards from the rotor shaft. These walls or wall sections can limit the receiving space between the end plate and the cover element in the circumferential direction. At least one other wall or wall section can, for example, extend at least substantially parallel to the rotor shaft and at least substantially in a tangential direction or parallel to a tangent to the rotor shaft running in the principal planes of extension of the end plate and the cover element. This wall or wall section can limit the receiving space between the end plate and the cover element radially outwards, i.e., towards the rotor winding or its main part.

[0026] The fact that the recording space is at least substantially completely or at least substantially tightly enclosed by the walls can, in particular, mean that any openings, gaps, or slits are small enough, i.e., narrow enough, so that the elastic material, especially a silicone or a material with a similar viscosity, does not leak out, or does not leak out to a significant extent, during the recording process.

[0027] 18.02.202524-3542

[0028] 5

[0029] during hardening or crosslinking, it runs or flows out of the receiving space.

[0030] Thus, compared to conventionally constructed rotors, the additional walls or wall sections surrounding the connection contact and forming the receiving space allow the end plate's connection contact and the associated end of the winding wire to be easily, efficiently, and reliably completely encased in the elastic material by introducing it into the receiving space. In other words, appropriately adapted shapes in the end plate and / or the cover element can retain the elastic material in the area of ​​the connection contact during rotor manufacturing. These additional shapes, which ultimately form the side walls of the receiving space, can be created without significant additional effort during the manufacturing of the end plate and / or the cover element, as these components can already be relatively complex in shape and prefabricated separately.

[0031] During rotor manufacturing, for example, the receiving space can be completely filled with the elastic material in a single step. This eliminates the need to apply the elastic material in several thin layers around the connection contact to prevent leakage and ensure complete encapsulation of the contact and the connected end of the winding wire. This can simplify and accelerate rotor manufacturing.

[0032] In principle, the rotor can be filled with conventional potting compound to improve robustness. However, practical experience has shown that this conventional potting compound can break or crack during curing and / or operation of the rotor, particularly in the area of ​​the terminal contact or between it and the main part of the rotor winding along the section or end of the winding wire running between this main part of the rotor winding and the terminal contact. In conventional rotors, this can lead to a radially outer fragment of the cured potting compound being pulled by centrifugal forces on the corresponding section or end of the winding wire, thereby damaging or interrupting its electrical connection to the terminal contact of the end plate.

[0033] 18.02.202524-3542

[0034] 6

[0035] The elastic material additionally arranged according to the invention in the area of ​​the connection contact and the corresponding end of the winding wire extending from it can now also act as strain relief for the corresponding end of the winding wire or its connection to the connection contact in the event of breakage or tearing of the potting material, and, due to its greater elasticity, prevent the winding wire from breaking away from the connection contact. Effectively, the connection contact and the electrical connection there with the winding wire are thus encased multiple times: first by the elastic material and then, outside of that, by the potting material. This results in an overall improvement in the robustness and reliability of the rotor.

[0036] Several corresponding receiving spaces can be formed around the rotor shaft, spaced apart and distributed circumferentially. Each of these spaces can contain a connection contact and an electrically connected end of a winding wire, surrounded, cast into, or injected with the elastic material. For example, the rotor can have six poles and four connection contacts, and consequently four corresponding receiving spaces, which can be arranged, for instance, evenly distributed around the circumference.

[0037] In one possible embodiment of the present invention, the terminal contact comprises two electrical contact elements between which the winding wire, or its end or end region, is crimped. The terminal contact can thus, for example, initially be fork-shaped with the two electrical contact elements open towards the outer end face. The winding wire can then be inserted between these two contact elements. The two contact elements can then be pressed together to permanently hold and connect the winding wire. The contact elements and / or the corresponding end of the winding wire can also be heated to ensure particularly good electrical contact. In the manner proposed here, the winding wire can be positioned at the terminal contact particularly easily and a secure and reliable electrical connection can be established.

[0038] In another possible embodiment of the present invention, the cover element has, in the area of ​​the receiving space, on its side facing the end plate

[0039] 18.02.202524-3542

[0040] 7

[0041] On the axially outer end face, facing away from the surface, is a filling opening for filling the elastic material into the respective receiving chamber. The filling opening can be, for example, a hole or a filling nozzle. By positioning the filling opening on the axially outer end face, the elastic material can be filled axially into the receiving chamber. This ensures particularly easy access for a filling tool to the receiving chamber or the filling opening. This, in turn, enables or facilitates simple, quick, and reliable filling of the receiving chamber and thus ultimately also the corresponding manufacturing of the rotor as a whole.

[0042] In another possible embodiment of the present invention, the cover element is a sleeve carrier, or the cover element functions as a sleeve carrier, which has sleeves for screwing it to the end plate. Correspondingly, the end plate can then have corresponding threads. The sleeve carrier can serve as a spacer element and / or for creating a clamping force and / or, for example, as a carrier for a seal against the end face and / or against the rotor shaft to prevent leakage of the potting material. At the same time, the cover element can, as described, define the receiving space for the elastic material and thus be designed to be multifunctional. In this way, a simple, compact, and robust rotor design can be achieved overall.

[0043] In a further possible embodiment of the present invention, walls of the receiving chamber, arranged circumferentially around the rotor or around the rotor shaft on both sides of the connection contact and perpendicular to the main extension planes of the end disk and the cover element, which extend at least substantially to the rotor shaft, are part of the end disk. A wall of the receiving chamber, also perpendicular to the main extension planes of the end disk and the cover element, which is at least substantially parallel to a tangential plane to the rotor shaft and extends radially outwards to the receiving chamber, for example towards the main part or the winding head of the rotor winding, is part of the cover element. This latter wall, formed as part of the cover element, can in particular abut the passage for the winding wire or form an edge of this passage.This wall can also be referred to as the outer tangential wall. This tangential wall does not necessarily have to be completely flat or planar, but can be.

[0044] 18.02.202524-3542

[0045] 8

[0046] For example, the tangential wall may be curved or arched around the rotor shaft. Due to its relatively short circumferential length, the tangential wall can also extend along the rotor shaft, at least essentially parallel to the tangential plane. Because the tangential wall is part of the cover element, the winding wire can be easily guided to the terminal contact and electrically connected to it before the cover element is attached. Simultaneously, because the other walls of the receiving space are part of the end plate, the cover element can be easily fitted. These end plate walls, which define the receiving space circumferentially on both sides, can also be called radial walls. These radial walls can extend radially outwards from the rotor shaft.Likewise, the radial walls can, for example, be parallel to each other and / or offset or tilted relative to a respective radial direction, so that they would not intersect the central axis of rotation of the rotor shaft or the rotor as a whole if extended imaginarily.

[0047] The exact arrangement and course of the radial walls as well as the tangential wall can be chosen flexibly and according to requirements in each individual case.

[0048] Because the radial walls extend at least substantially to the rotor shaft, the rotor shaft itself can function as a wall of the receiving space. The rotor shaft, or a corresponding section of it, can, for example, run at least substantially or approximately parallel to the outer tangential wall and therefore also be referred to as the inner tangential wall. Since the receiving space is radially bounded on the inside by the rotor shaft, a corresponding additional wall, such as a part or feature of the end plate or cover element, can be eliminated. This can save material, weight, installation space, and complexity.

[0049] Due to the viscosity of the elastic material, a gap or slot can remain between the rotor shaft and the radial walls without significant leakage of the elastic material. Therefore, precise conformity of the radial walls to the rotor shaft is not necessary, thus enabling or supporting a correspondingly simple and cost-effective manufacturing process.

[0050] 18.02.202524-3542

[0051] 9

[0052] The present invention also relates to a method for manufacturing the rotor according to the invention. In this method, the winding carrier is provided and wound with the winding wire, and the rotor shaft is connected to the winding carrier. The sequence of these two steps can be selected as required. In a further step of the method according to the invention, the end plate is arranged to cover the winding carrier. This can be done just before the winding carrier is wound with the winding wire. Then, one end of the winding wire is connected to the terminal contact of the end plate, and the cover element is placed on the end plate and fastened. Only then is the at least one receiving space filled with the elastic material. Afterward, and in particular after a waiting period for the elastic material to harden or crosslink, the rotor is encased in the potting compound.The process may also include further, possibly optional, process steps, for example for attaching additional parts or components.

[0053] In a potential advanced training process, the opening for the winding wire—that is, the point where the winding wire enters and exits the opening—is monitored by a camera while the receiving chamber is being filled with the elastic material. The filling of the elastic material into the receiving chamber is then automatically stopped if the camera detects any leakage of the elastic material at the opening, based on camera images or data. This allows at least part of the rotor manufacturing process to be automated. For example, to account for tolerances in the routing of the winding wire to the connection contact, the receiving chamber around the winding wire can be configured to have the largest gap or...

[0054] exhibit leakage. Accordingly, the elastic material can reliably escape there as soon as the receiving chamber is completely filled and further elastic material is introduced. Furthermore, for the described effect of the elastic material to improve robustness, it can be particularly important or beneficial that the winding wire is encased in the elastic material. This can be achieved if the elastic material emerges around the winding wire at the feedthrough. Thus, the emergence of the elastic material at the feedthrough, as used here, represents a useful criterion for stopping the filling of the receiving chamber with the elastic material.

[0055] 18.02.202524-3542

[0056] 10

[0057] In a possible embodiment of the present invention, the pressure of the elastic material in a filling tool is monitored by means of a pressure sensor during the filling of the receiving chamber. Such a filling tool can be, for example, a filling nozzle or filling hose, or a pump or press for conveying the elastic material into the receiving chamber. The filling of the elastic material into the receiving chamber is then automatically stopped when the pressure reaches or exceeds a predetermined value, or when a predetermined pressure increase is detected. Even if the receiving chamber is not completely sealed all around from the environment, an increased or rising pressure can occur during or immediately after the receiving chamber is completely filled with the elastic material due to its viscosity. Thus, the pressure can be used to detect whether or not the filling process has been interrupted.when the receiving chamber is completely filled with the elastic material. Thus, pressure or pressure increase can be used as a criterion for detecting complete filling of the receiving chamber with the elastic material. The pressure sensor can be positioned at a certain distance from the receiving chamber itself, for example, in a feeder or storage container for the elastic material. This allows the complete filling of the receiving chamber to be detected without, for example, specific requirements regarding visibility within the receiving chamber.

[0058] The present invention also relates to an electric machine with the separately excited rotor according to the invention and a stator that surrounds the rotor and to which the rotor is movably mounted. The electric machine can be designed or configured, in particular, as a traction machine for a motor vehicle. However, other applications, configurations, or embodiments of the electric machine according to the invention are also possible.

[0059] The present invention also relates to a motor vehicle equipped with the electric machine according to the invention. In particular, the electric machine according to the invention can be a traction machine of the motor vehicle according to the invention.

[0060] Further features of the invention may become apparent from the claims, the figures, and the description of the figures. The features mentioned above in the description

[0061] 18.02.202524-3542

[0062] 11

[0063] and combinations of features as well as the features and combinations of features shown below in the figure description and / or in the figures alone are not only usable in the combination specified in each case, but also in other combinations or on their own, without leaving the scope of the invention.

[0064] The drawing shows in:

[0065] Fig. 1 shows a partial schematic representation of a separately excited rotor for an electric machine in an intermediate state during manufacturing;

[0066] Fig. 2 shows a partial schematic representation of the rotor in a later intermediate state during manufacturing;

[0067] Fig. 3 shows a schematic representation of a motor vehicle with the electric machine as the traction machine; and

[0068] Fig. 4 shows a partial schematic flowchart for a method for manufacturing the rotor.

[0069] In the figures, identical and functionally equivalent elements are provided with the same reference symbols.

[0070] Fig. 1 shows a partial schematic representation of a separately excited rotor 1 in a partially assembled state. The rotor 1 comprises a central rotor shaft 2 and several rotor poles 3. The rotor poles 3 are formed by winding wires wound onto a winding carrier, i.e., each rotor winding 4. In the state shown here, a radially inner part of the winding carrier is covered by an end plate 5, which surrounds the rotor shaft 2 in an annular manner and can extend radially, for example, to the rotor windings 4 or corresponding winding heads.

[0071] The end disk 5 has two electrical contact elements on its axial outer surface, or outer end face, which form a connection contact 6. One end of the corresponding rotor winding 4, shown here as primary, is connected to this contact.

[0072] 18.02.202524-3542

[0073] 12

[0074] The winding wire, acting as contact wire 7, is guided radially inwards over the end plate 5 and to the connection contact 6. Here, the contact wire 7 is shown, by way of example, placed between the two contact elements of the connection contact 6.

[0075] In a subsequent manufacturing step, any remaining cavities or gaps in the rotor 1 can be filled with an electrically insulating potting compound, which then hardens. To elastically decouple the connection contacts and the attached contact wire 7 from this potting compound, the connection contact 6 and the contact wire 7 can be encased with an elastic material, such as silicone or polyorganosiloxane. However, due to the comparatively low viscosity of liquid silicone, a very high material input is currently required to reliably cover or encase the connection contact 6 and the attached end of the contact wire 7. Furthermore, this ultimately results in an undefined shape for the silicone coating, which can lead to inconsistent and unpredictable behavior.

[0076] To address this problem, the connection contact 6 and the end of the contact wire 7 connected to it are enclosed by walls or wall sections that retain the elastic material, i.e., the silicone, in the area of ​​the connection contact 6. This is schematically indicated here by side walls 8 and a tangential wall 9. The side walls 8 can delimit the connection contact 6 circumferentially around the rotor shaft 2 on both sides from the surrounding environment. The tangential wall 9 serves as a barrier to the rotor winding 4, i.e., radially outwards. Radially inwards, the rotor shaft 2 can act as a wall. Thus, the end plate 5, the side walls 8, the tangential wall 9, and the rotor shaft 2 can define a receiving space 10 in which the connection contact 6 is located. Instead of the rotor shaft 2, an additional lower or inner tangential wall could also be provided.The receiving chamber 10 has a feedthrough opening 11 through which the contact wire 7 is guided into the receiving chamber 10. In contrast to the illustration shown here, the outer tangential wall 9 could also be arranged, for example, closer to the terminal contact 6, so that the contact wire 7 could then, for example, extend radially outwards through the feedthrough opening 11.

[0077] 18.02.202524-3542

[0078] 13

[0079] For further illustration, Fig. 2 shows a partial schematic representation of the rotor 1 at a later point or step during manufacturing. Here, the end disk 5 is covered by a cover element, which in this case is a sleeve carrier 12. This sleeve carrier 12 has screw sleeves 13 as spacers to the end disk 5 and as guides for screws for fastening to the end disk 5 and / or the winding carrier. The sleeve carrier 12 also forms a front wall 14, which covers the receiving chamber 10 axially to the outside. A filling opening 15 is provided in this front wall 14. In the state shown here, the elastic material can be filled into the receiving chamber 10 through this filling opening 15.

[0080] For example, the side walls 8 can be part of the end plate 5 and the tangential wall 9 part of the sleeve carrier 12. Other configurations or designs are also possible. In total, there can be features or geometries on the outer surface of the end plate 5 and / or on an inner surface of the sleeve carrier 12 facing it, which interlock precisely and thus form the defined, or at least nearly enclosed, receiving space 10. This can then function analogously to a casting mold to hold the elastic material or silicone filled into it around the connection contact 6. Only the contact wire 7, which runs from there into the rotor winding 4, can protrude from the receiving space 10.

[0081] The defined receiving space 10 allows the volume, i.e., the amount of elastic material, to be reduced to a minimum, preventing the elastic material from running or flowing uncontrollably into surrounding areas of the rotor 1 during manufacturing. Furthermore, the introduction of the elastic material through the filling opening 15 is comparatively precisely defined, and there is, for example, no stringing caused by machine application with a nozzle that moves back and forth over the connection contact 6, or similar processes.

[0082] After the receiving chamber 10 has been filled with the elastic material, any remaining cavities or spaces in the rotor 1 can be filled or cast with a conventional potting material.

[0083] To illustrate an application for the rotor 1, Fig. 3 shows a partial schematic representation of a motor vehicle 16 with an electric

[0084] 18.02.202524-3542

[0085] 14

[0086] Machine 17. This electric machine 17 comprises the rotor 1 and a stator and serves as a traction machine, i.e., to drive the motor vehicle 16. The electric machine 17 can also be operated, for example, in generator mode.

[0087] Fig. 4 shows an exemplary schematic flow chart 18 for a method for manufacturing the rotor 1. In process step S1, the winding carrier can be connected to the rotor shaft 2. In process step S2, the end disk 5 can be slid onto the rotor shaft 2 and optionally connected to the winding carrier. In process step S3, the winding carrier can be wound with the winding wire and its end connected as a contact wire 7 to the terminal contact 6 of the end disk 5.

[0088] Similarly, at least some of these procedural steps can be carried out in a different order.

[0089] In process step S4, the sleeve carrier 12 is placed onto the rotor shaft 2 and the end plate 5 and screwed into place. In process step S5, for example, a silicone nozzle can be attached to the filling opening 15 and the receiving chamber 10 filled with the elastic material. In process step S6, the rotor 1 can be potted or encased with the electrically insulating potting compound.

[0090] The rotor 1 produced in this way can then be combined with the stator to form the electric machine 17.

[0091] Overall, the examples described show how a potting chamber consisting of at least two components for filling with silicone can be formed and used to support contact wires of a separately excited rotor 1.

[0092] 18.02.202524-3542

[0093] 15

[0094] Reference symbol list

[0095] 1 Rotor

[0096] 2 Rotor shaft

[0097] 3 Rotor pole

[0098] 4 Rotor winding

[0099] 5 Front disc

[0100] 6 connection contacts

[0101] 7 Contact wire

[0102] 8 side walls

[0103] 9 Tangential wall

[0104] 10 Recording room

[0105] 11 Implementation opening

[0106] 12 shell carriers

[0107] 13 Screw sleeve

[0108] 14 Front wall

[0109] 15 Filling opening

[0110] 16 motor vehicle

[0111] 17 electric machine

[0112] 18 Schedule

[0113] S1-S6 process steps

[0114] February 18, 2025

Claims

24-3542 16 Patent claims 1. Externally excited rotor (1) for an electric machine (17) with - a winding support and at least one winding wire wound around the winding support to form a rotor winding (4), - a front disk (5) perpendicular to the intended axis of rotation of the rotor (1), which at least partially covers a radially inner part of the winding carrier in an axial end region of the rotor (1), thereby surrounding a rotor shaft (2) of the rotor (1) in a ring shape and having an electrical connection contact (6) on its axially outer end face radially inside the rotor winding (4), where - one end (7) of the winding wire is led radially inwards from the rotor winding (4) to the connection contact (6) and is electrically connected to it, - the end plate (5) including the connection contact (6) is covered by means of a cover element (12) arranged parallel to it and axially outside of it, - the end plate (5) and the cover element (12) together form walls (8, 9) of a receiving space (10) which surround the connection contact (6) at least substantially completely or except for a single passage (11) through which the winding wire (7) is led from the receiving space (10) to the rotor winding (4), - the receiving space (10) is narrower in the circumferential direction than a pole (3) of the rotor (1), - the receiving chamber (10) is filled with an electrically insulating elastic material and surrounding areas of the rotor (1) are filled with a comparatively firmer electrically insulating potting material.

2. Rotor (1) according to any one of the preceding claims, characterized by the fact that the connecting contact (6) comprises two electrical contact elements between which the winding wire (7) is crimped. 18.02.202524-3542 17 3. Rotor (1) according to any one of the preceding claims, characterized by the fact that the lid element (12) has a filling opening (15) on its axially outer end face facing away from the end plate (5) in the area of ​​the receiving space (10) for filling the elastic material into the receiving space (10).

4. Rotor (1) according to any one of the preceding claims, characterized by the fact that the cover element (12) is a sleeve carrier (12) which has sleeves (13) for screwing to the end plate (5).

5. Rotor (1) according to any one of the preceding claims, characterized by the fact that Walls (8) of the receiving space (10) arranged circumferentially on both sides of the connection contact (6), perpendicular to the main extension planes of the end disk (5) and the cover element (12), which extend at least substantially to the rotor shaft (2), are part of the end disk (5), and a wall (9) of the receiving space (10) also perpendicular to the main extension planes of the end disk (5) and the cover element (12), which extends at least substantially parallel to a tangential plane to the rotor shaft (2) and radially outwards bounds the receiving space (10), is part of the cover element (12).

6. Method (18) for manufacturing the rotor (1) according to one of the preceding claims, wherein the winding carrier is provided and wound with the winding wire, the rotor shaft (2) is connected to the winding carrier, the end plate (5) is arranged to cover the winding carrier, one end (7) of the winding wire is connected to the connection contact (6) of the end plate (5), the cover element (12) is placed on the end plate (5) and fastened, then the receiving space (10) is filled with the elastic material and then the rotor (1) is potted with the potting material.

7. Method (18) according to claim 6, characterized by the fact that 18.02.202524-3542 18 When filling the receiving space (10) with the elastic material, the opening (11) for the winding wire (7) is observed by means of a camera and the filling of elastic material into the receiving space (10) is automatically stopped if the camera detects an escape of the elastic material at the opening (11).

8. Method (18) according to claim 6 or 7, characterized by the fact that When filling the receiving chamber (10) with the elastic material, the pressure of the elastic material in a filling tool is monitored by means of a pressure sensor, and the filling of elastic material into the receiving chamber (10) is automatically stopped when the pressure reaches or exceeds a predetermined value.

9. Electric machine (17), in particular as a traction machine (17) for a motor vehicle (16), with a separately excited rotor (1) according to one of claims 1 to 5 and a stator that surrounds the rotor (1) and to which the rotor (1) is movably mounted.

10. Motor vehicle (16) with an electric machine (17) according to claim 9. February 18, 2025

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