Slip ring module and rotor for an electric machine

Abstract

The invention relates to a slip ring module (1) for the rotor (2) of an electric machine (3), in particular for a separately excited rotor of a synchronous machine. The slip ring module consists of an electrically insulating plastic main part (4) and a first slip ring (5) and a second slip ring (6) which are rotationally rigidly fastened to the main part (4). Two electric conductors (8, 9) electrically connect the slip rings: the first conductor (8) runs axially and radially through the module and terminates in a third contact portion (13), and the second conductor (9) likewise has an axial and radial region of extent and terminates in a fourth contact portion (16). The two conductors are for the most part enclosed by the plastic of the main part and thus fixed in order to ensure a stable electric connection.

Description

[0001] P240739

[0002] - 1 -

[0003] Slip ring module and rotor for an electric machine

[0004] The present invention relates to a slip ring module for a rotor of an electric machine, in particular for a separately excited rotor of a synchronous machine, comprising a base body formed from an electrically insulating plastic, a first slip ring and a second slip ring each arranged non-rotatably on a slip ring seat of the base body, a first electrical conductor which is electrically conductively connected to the first slip ring via a first electrical contact section, and a second electrical conductor which is electrically conductively connected to the second slip ring via a second electrical contact section, wherein the first electrical conductor has a first axial extension area which extends axially away from the slip ring seat through the slip ring module and has a first radial extension area.which adjoins the first axial extension area and at whose distal end a third electrical contacting section is formed, and the second electrical conductor has a second axial extension area that extends axially away from the slip ring seat through the slip ring module, as well as a second radial extension area that adjoins the second axial extension area and at whose distal end a fourth electrical contacting section is formed.

[0005] Slip ring modules for rotors of electrical machines, especially for separately excited synchronous machines, are widely used solutions to ensure a reliable electrical connection between stationary and rotating components. A typical slip ring module usually consists of several slip rings mounted on a rotor and electrical conductors that enable the transmission of power or signals. Although these modules are technically mature, the known solutions still have several disadvantages, particularly concerning mechanical stability, axial size, and manufacturing costs. P240739

[0006] - 2 -

[0007] A common design for a slip ring module, widely used in practice, features a three-part shaft. However, this design presents several problems. Firstly, the three-part construction leads to a cumulative effect of tolerances, which can result in inaccuracies such as runout. These inaccuracies cause imbalances that can negatively impact the smooth running and efficiency of the system. Another issue is that the required cable routing causes the bearing surfaces of the shaft to become uneven or wavy. This reduces bearing life and increases the system's susceptibility to wear or even premature bearing failure. Furthermore, the manufacturing costs are relatively high due to the three-part shaft design, as more complex manufacturing processes and tighter tolerance requirements must be met.

[0008] Another technical problem arises from the axial size of the slip ring module. Due to the necessary air and creepage distances between the slip rings and the conductive parts, a minimum clearance must be maintained to ensure electrical insulation. However, this clearance significantly increases the axial installation space of the entire module. This is particularly problematic in applications where available installation space is limited, as larger modules are more difficult to integrate and mount.

[0009] An alternative approach to reducing these problems is to use a shaft with two wide slots instead of the three-part shaft, as proposed in another known solution. However, this design also has significant drawbacks. The wide slots, necessary for cable routing, also affect the bearing contact surface. This uneven surface reduces bearing life and can lead to noise, vibration, and harshness (NVH) issues, which is particularly detrimental in noise-sensitive applications. Furthermore, the problem of axial size remains with this solution, as the clearances and creepage distances still have a significant impact on the distances between the slip rings and the conductive components, thus increasing the axial length of the slip ring module. P240739

[0010] - 3 -

[0011] It is therefore an object of the invention to provide a slip ring module for a rotor of an electric machine, in particular for a separately excited rotor of a synchronous machine, that avoids or at least reduces the problems known from the prior art. It is also an object of the invention to realize a correspondingly optimized rotor.

[0012] This problem is solved by a slip ring module for a rotor of an electric machine, in particular for a separately excited rotor of a synchronous machine, comprising a base body formed from an electrically insulating plastic, as well as a first slip ring and a second slip ring each arranged non-rotatably on a slip ring seat of the base body, as well as a first electrical conductor which is electrically conductively connected to the first slip ring via a first electrical contact section, and a second electrical conductor which is electrically conductively connected to the second slip ring via a second electrical contact section, wherein the first electrical conductor has a first axial extension area which extends axially away from the slip ring seat through the slip ring module and has a first radial extension area.which adjoins the first axial extension area and at whose distal end a third electrical contacting section is formed, and the second electrical conductor has a second axial extension area that extends axially away from the slip ring seat through the slip ring module, as well as a second radial extension area that adjoins the second axial extension area and at whose distal end a fourth electrical contacting section is formed, wherein the first electrical conductor and the second electrical conductor are at least partially, preferably completely except for the electrical contacting sections, enclosed by the plastic of the base body and thus fixed in the base body.

[0013] This slip ring module according to the invention offers the advantage that the electrical conductors are firmly fixed within the base body by being completely encased in plastic. This significantly increases the structural stability of the slip ring module, as the conductors are reliably held in place and no P240739

[0014] - 4 -

[0015] Relative movements or vibrations can occur, potentially leading to mechanical wear or electrical contact problems. Furthermore, this fixed design improves conductor insulation, minimizing the risk of short circuits or unwanted electrical connections. From an economic perspective, this design enables cost-effective manufacturing, as the integration of the conductors into the plastics processing is easily automated, reducing the number of components required. Additionally, the slip ring module can be easily mounted onto a rotor as a single component.

[0016] The present invention thus relates to a slip ring module for a rotor of an electric machine, in particular for a separately excited synchronous machine, which is characterized by an optimized design of the current conduction elements as well as - as will be explained in more detail later - the mounting slots in the shaft body, which leads to an improved bearing life, optimized noise, vibration and roughness properties (NVH) and a reduced axial size.

[0017] A further significant advantage of the present invention lies in the optional possibility of subsequently optimizing the slip ring module through precise mechanical machining, in particular by turning or milling an insulation slot. This insulation slot is formed axially between the slip rings in the electrically insulating base body of the slip ring module. The base body preferably consists of a plastic material, typically formed by injection molding. After the base body has been manufactured, the insulation slot itself is precisely machined by turning or milling at the points where the electrical conductors run within the slip ring module. The precise placement and machining of the insulation slot improves the overall electrical insulation within the module by optimizing the distances between the electrical conductors and conductive components in the rotor.The key advantage of this post-processing is that it reduces the required creepage distance without impairing the module's insulating function. Since the plastic from which the base body is made has high electrical insulation properties, the insulation slot can be designed to precisely meet electrical safety requirements while simultaneously minimizing the installation space. P240739.

[0018] - 5 -

[0019] By reducing creepage distances, for example in the axial direction, the overall length of the slip ring module can be significantly shortened. This is particularly advantageous in applications where available installation space is limited. In many electrical machines, such as synchronous machines, axial installation space is a critical design factor, as excessive size can lead to inefficient use of space and higher production costs. Precise post-processing of the insulation slot can considerably reduce the axial size of the slip ring module, enabling a more compact design.

[0020] Another important aspect of post-processing by turning or milling is the flexibility these processes offer. The depth, width, and exact shape of the insulation slot can be precisely adapted to the specific electrical and mechanical requirements of the respective slip ring module. This allows the insulation slot to be designed in such a way that it meets the necessary safety requirements for electrical insulation while remaining as compact as possible to minimize the axial size. Furthermore, precise milling or turning makes it possible to create a surface of the insulation slot that is so smooth and uniform that potential electrical arcing is prevented.

[0021] Machining the insulation slot not only offers advantages in terms of electrical insulation and size, but also improves the mechanical stability of the slip ring module. Since the insulation slot is precisely positioned where electrical isolation is required, the rest of the slip ring module remains mechanically stable and robust. This is particularly important for the module's longevity, as it avoids mechanical weak points caused by inaccurate or unnecessarily wide insulation areas. The invention thus also enables, in particular, the targeted optimization of the electrical and mechanical properties of the slip ring module. P240739

[0022] - 6 -

[0023] First, the individual elements of the claimed subject matter of the invention are explained in the order in which they are mentioned in the claim set, and subsequently, particularly preferred embodiments of the subject matter of the invention are described.

[0024] grinding ring module

[0025] For the purposes of this patent application, a slip ring module is an assembly used in the rotor of an electric machine, particularly in the separately excited rotor of a synchronous machine, for transmitting electrical signals or currents. The slip ring module consists of a base body made of an electrically insulating plastic and at least two slip rings that are fixed against rotation on a slip ring seat of the base body. These slip rings are connected to electrical contact sections via electrical conductors that extend partially axially and radially through the module. The base body encloses the conductors, at least partially, so that they are fixed in position and mechanically protected.

[0026] The function of the slip ring module is therefore primarily to ensure a reliable and stable electrical connection between the stationary and rotating parts of the machine. The special arrangement of the conductors and slip rings enables efficient and low-loss transmission of electrical energy. The insulating base not only provides mechanical stabilization of the conductors but also the necessary electrical insulation to prevent short circuits and electrical flashovers.

[0027] Possible embodiments of the slip ring module include variants in which the electrical conductors are formed as a single unit as busbars or are constructed in multiple parts, with individual contact sections attached separately to the conductor. These modular variants allow for flexible adaptation to different mechanical and electrical requirements. Furthermore, the conductors can have different cross-sectional shapes, such as rectangular or circular, to achieve an optimal balance between space requirements, mechanical strength, and electrical performance, depending on the application. In addition, the slip ring module can be designed to pass through various mounting and guide slots in the rotor, as described in P240739.

[0028] - 7 -

[0029] The geometry of these slots can further improve the stability and ease of assembly of the overall system.

[0030] For the purposes of this patent application, a base body is understood to be the supporting element of the slip ring module, which accommodates, stabilizes, and protects the module's essential components. The base body is made of an electrically insulating plastic material that ensures reliable and permanent insulation of the integrated electrical conductors. The conductors are completely or at least partially enclosed by the plastic of the base body, thereby fixing them firmly in position and preventing any relative movement. This contributes significantly to the mechanical stability and electrical safety of the entire slip ring module.

[0031] The main function of the base body is to mechanically support the slip rings and electrical conductors and hold them in their correct position. It ensures that the slip rings are securely mounted on their designated slip ring seats and that the electrical contact sections of the conductors are precisely positioned and insulated. This guarantees a reliable electrical connection while preventing short circuits and electrical flashovers.

[0032] The base body can be designed in various geometric shapes, depending on the specific requirements of the application. A preferred embodiment is a cylindrical or annular base body on which the slip rings are arranged concentrically, thus enabling a uniform distribution of mechanical loads. Alternatively, the base body can also have a more complex geometry to optimally adapt to the available installation space and assembly requirements.

[0033] Preferably, the base body is made of a heat-resistant and mechanically robust plastic material that offers high insulation properties and resistance to external influences. In certain versions, the base body can also be reinforced, for example, with fiberglass. P240739

[0034] - 8 - to ensure additional mechanical strength. One possible variation of the base body is to provide integrated cooling structures or channels that enable efficient heat dissipation and thus reduce the thermal load on the slip ring module.

[0035] slip ring

[0036] For the purposes of this patent application, a slip ring is to be understood as a ring-shaped component mounted on a base body of a slip ring module and used to transmit electrical energy between the stationary and rotating parts of an electric machine. The slip ring is preferably made of a conductive material that ensures uniform and reliable current transmission while simultaneously withstanding the mechanical stress caused by the rotation of the rotor.

[0037] The slip ring is preferably designed to establish electrical contact with stationary brushes or contact springs that remain in contact with the outer surface of the slip ring as it rotates. This contact enables the continuous transmission of electrical current or signals between the rotating and stationary parts of the machine. Advantageously, the slip ring comprises a conductive core that ensures current transmission and an outer layer made of a material that reduces mechanical friction and increases the slip ring's service life.

[0038] The slip ring can be made of various materials, depending on the specific requirements of the application. For example, conductive metals such as copper or special alloys can be used to maximize electrical efficiency while minimizing wear from friction.

[0039] Possible designs of the slip ring include various geometric configurations to accommodate different space constraints and performance requirements. For example, the slip ring can advantageously be manufactured in different diameters and widths to adapt to the specific dimensions of the rotor. The outer surface of the slip ring can also be designed differently, for example, smooth or with special grooves or P240739.

[0040] - 9 -

[0041] Coatings that further reduce friction or improve heat dissipation. In some embodiments, the slip ring can also consist of several segmented parts that together form a ring-shaped structure, which can facilitate assembly and allow adaptation to different rotor geometries.

[0042] For the purposes of this patent application, a slip ring seat is a defined surface or area on the base body of the slip ring module on which a slip ring is mounted in a rotationally fixed manner. The slip ring seat serves to mechanically fix the slip ring and simultaneously ensure precise positioning to enable a reliable mechanical connection and electrical contact. The slip ring seat is designed to hold the slip ring in its position and prevent it from shifting or loosening during operation.

[0043] The design of the slip ring seat can vary depending on the embodiment. It is preferably formed from the same electrically insulating plastic material as the base body of the slip ring module to create a homogeneous and stable structure. The slip ring seat can be designed as a raised surface or as a specially shaped receptacle that positively engages and secures the slip ring. Advantageously, the slip ring seat can also have a special surface structure that increases the friction between the slip ring and the base body to ensure even more secure fixation.

[0044] Possible embodiments of the slip ring seat further include a flat surface on which the slip ring is press-fitted, or a recess into which the slip ring is precisely inserted and secured by an additional retaining device, such as a clamping device or a retaining ring. In another embodiment, the slip ring seat could also include elastic elements that allow a certain degree of flexibility to absorb mechanical stresses and extend the service life of the slip ring. Furthermore, it is possible for the slip ring seat to have an anti-rotation device, P240739

[0045] - 10 - for example in the form of projections or ribs that engage in corresponding recesses on the slip ring and thus ensure a rotationally fixed connection.

[0046] Electrical conductor

[0047] For the purposes of this patent application, an electrical conductor is a component that serves to reliably transmit electrical energy within the slip ring module from one point to another. The electrical conductor establishes a continuous electrical connection between the slip rings and the corresponding electrical contact sections.

[0048] The electrical conductor can be made of a material with high electrical conductivity, such as copper or aluminum. These materials are preferred because they have low specific resistance, thus enabling current flow with minimal energy loss. The construction of the electrical conductor can vary depending on the specific requirements of the application. For example, the conductor can be a single, continuous busbar, ensuring high mechanical stability and efficient current transmission. Alternatively, the conductor can be multi-sectioned, with individual segments connected together. This allows for greater flexibility in adapting to the module's geometry and facilitates assembly and maintenance.

[0049] Preferably, the electrical conductor is designed such that it is partially, and preferably completely, enclosed by the plastic of the base body. This offers the advantage of secure fixation and improved insulation, thereby preventing short circuits. It is also conceivable that in other areas of the module the conductor may be exposed to allow for easy contact with other electrical components.

[0050] Possible embodiments of the electrical conductor include a rectangular or circular cross-sectional shape, depending on the mechanical and electrical requirements placed on the slip ring module. A rectangular shape allows for a compact design and efficient use of space, P240739

[0051] - 11 - while a circular shape advantageously offers higher mechanical strength and flexibility. Furthermore, in certain designs, the conductor can be adapted by bending or shaping so that it can be optimally integrated into the intended structure of the module. This allows for targeted control of the current flow and improved mechanical stability of the entire system.

[0052] Axial extension range

[0053] For the purposes of this patent application, an axial extension area is a section of an electrical conductor that extends in the axial direction, i.e., along the axis of rotation of the slip ring module or the rotor. The axial extension area serves to guide the electrical conductor through the slip ring module and enables the electrical connection between the slip rings and the corresponding external terminals. This area is designed to extend away from the position of the slip ring seat and pass through the base body of the slip ring module.

[0054] The axial extension area can have various cross-sectional shapes depending on the requirements of the specific application. For example, the cross-section can be rectangular to enable a compact design and achieve optimal space utilization within the module. Alternatively, the cross-section can be circular to achieve a uniform distribution of mechanical loads and increase robustness against axial and radial forces.

[0055] The conductor can be manufactured from a single piece of material in its axial extension to maximize mechanical strength and minimize electrical contact resistance. Alternatively, the axial extension can be constructed in multiple sections, for example, by connecting individual sections using special contact sections. This modular design allows for more flexible adaptation of the conductor to the specific requirements of the module. P240739

[0056] - 12 -

[0057] Advantageously, the axial extension area is completely enclosed by the plastic of the base body, resulting in increased insulation and secure fixation of the conductor within the module. This enclosure protects the conductor from mechanical influences and ensures that no relative movement occurs between the conductor and the base body that could lead to wear or damage.

[0058] The extension area can be rectangular or circular, as described, but other geometric shapes such as oval or polygonal are also possible, depending on the specific requirements for mechanical strength and electrical conductivity. Preferably, the axial extension area can also have a taper or widening along its length to allow adaptation to different mechanical or thermal loads.

[0059] Electrical contact section

[0060] For the purposes of this patent application, an electrical contact section is a specific area of ​​an electrical conductor designed to establish an electrical connection to another component or an external electrical system. This section is designed to ensure reliable and stable transmission of electrical currents by being in electrically conductive contact with the component to be connected, either directly or via additional contact elements.

[0061] The contact section can be made of a material with high electrical conductivity, such as copper or a copper alloy, and is preferably optimized by a special surface coating, such as silver or gold plating, to minimize contact resistance and increase corrosion resistance.

[0062] The design of the electrical contact section can take various forms, depending on the specific requirements of the application. Preferably, the contact section can be designed as a flat or rod-shaped element that is inserted and fixed either into an opening, a slot, or directly into another component. In another P240739

[0063] - 13 -

[0064] In one embodiment, the contact section can be designed as a flexible element to adapt to the geometry of the component to be joined. Advantageously, the contact section can also include a spring-loaded contact mechanism that ensures a permanent contact force and thus a secure electrical connection, even under conditions that could lead to relative movement between the joined components.

[0065] It is also conceivable that the electrical contact section is designed in a modular form, allowing it to be easily replaced or adapted to ensure an optimal connection for different applications. This can be particularly advantageous if the slip ring module is to be used in different types of machines or under different operating conditions.

[0066] Advantageously, the electrical contact section is formed in one piece, preferably monolithically, with the electrical conductor.

[0067] Radial extension range

[0068] For the purposes of this patent application, a radial extension area of ​​an electrical conductor is a section of the conductor that extends radially inwards or outwards from an axial extension area of ​​the conductor in a direction perpendicular to the axis of the rotor or slip ring module. This area enables the spatial separation and positioning of the electrical contact points in the radial direction, thereby ensuring optimal connection to other components or connection points. The radial extension area thus establishes the electrical connection from the axial conductor section to the more distant components.

[0069] The radial extension area can have various cross-sectional shapes, with a rectangular or circular cross-section being particularly preferred, as these shapes offer a good balance between mechanical strength and electrical conductivity. One embodiment of the radial extension area could have a rectangular cross-section to enable a flat and compact design, which is particularly advantageous in confined installation spaces.

[0070] - 14 -

[0071] This is an advantage. Another embodiment could have a circular cross-section to increase mechanical strength and ensure a uniform stress distribution.

[0072] Furthermore, the radial extension area can also include an additional insulating layer that protects the conductor from external influences and increases electrical safety. This insulation is particularly important in environments with high voltages or strong electromagnetic fields, as it minimizes the risk of short circuits or flashovers.

[0073] Advantageously, the radial extension area is formed in one piece, preferably monolithically, with the axial extension area of ​​the conductor.

[0074] Guide section

[0075] For the purposes of this patent application, a guide section is a specially shaped section of an electrical conductor within a slip ring module, which serves to precisely guide and stabilize the conductor in a defined position during assembly in a rotor and allows targeted guidance and positioning in a narrow guide slot of the rotor.

[0076] The function of the guide section is therefore primarily to insert the conductor securely and precisely into the designated guide slots of the rotor during assembly and to hold it there in a defined position. The geometry of the guide section ensures that the conductor remains stable in its position, which increases the mechanical stability of the entire slip ring module and the rotor. This helps to prevent deformations or misalignments that could impair the function and service life of the module.

[0077] The guide section is designed with a specific shape in which the axial extent is significantly greater than the circumferential extent. This shape allows the conductor to be inserted into the rotor through a narrow slot, thus improving the integrity and stability of the rotor. Preferably, the guide section is an integral part of the electrical conductor P240739.

[0078] - 15 - is executed, but can also be designed as a separate component that is connected to the conductor.

[0079] Possible embodiments of the guide section include various cross-sectional geometries. For example, the guide section can be rectangular or trapezoidal to ensure an optimal fit in a corresponding guide slot. Preferably, additional coatings or surface treatments can also be provided to protect the guide section against mechanical wear or corrosion.

[0080] Support element

[0081] For the purposes of this patent application, a support element is to be understood as a component that serves to mechanically stabilize and fix an electrical contact section within a rotor, in particular to protect it from the stresses that may occur during operation due to centrifugal forces or vibrations. The support element preferably surrounds the contact section, at least partially, and lies close to the outer surface of the rotor. This mechanical support prevents unintentional movement or displacement of the contact section and ensures that the electrical contact remains permanent and reliable.

[0082] The support element is designed to efficiently transfer the forces to the surrounding rotor structure, thereby minimizing the mechanical stress on the electrical conductor and the contact section itself. In its construction, the support element is preferably made of a rigid yet easily deformable material that allows for a tight fit around the contact section while remaining sufficiently elastic to compensate for minor movements or thermal expansions without compromising its mechanical integrity.

[0083] Another aspect of the support element is that it can also provide a sealing function for the contact section against the rotor. This sealing function protects the contact section from the ingress of P240739.

[0084] - 16 -

[0085] Dust, moisture, or other foreign substances that could impair the electrical connections or cause corrosion are prevented from entering. This further increases the reliability and longevity of the electrical connection. Sealing is achieved through a tight fit of the support element, creating a tight seal between the contact section and the surrounding rotor structure.

[0086] Possible embodiments of the support element include, for example, a ring-shaped structure that completely encloses the contact section and distributes forces evenly across the rotor. Another possible embodiment is a segmented structure in which the support element consists of several parts that are joined together to encompass the contact section and press it against the rotor. This design can be particularly advantageous for contact section geometries with more complex geometries. Furthermore, the support element can be made of an insulating material to provide electrical insulation in addition to mechanical insulation, which is especially relevant in high-voltage applications.

[0087] Advantageous embodiments of the invention

[0088] According to an advantageous embodiment of the invention, the third contact section may have a first guide section extending radially outwards from the first axial extension area, the axial cross-sectional area of ​​which is larger than its circumferential cross-sectional area, and / or the fourth contact section may have a second guide section extending radially outwards from the second axial extension area, the axial cross-sectional area of ​​which is larger than its circumferential cross-sectional area. Advantageously, the specific design of the guide sections improves the mechanical stability and the precise positioning of the electrical contact sections within the module.The larger axial cross-sectional area provides greater resistance to axial forces, which is particularly advantageous during assembly and operation, as it prevents deformation or misalignment of the contacts. Another advantage of this design is that the guide slots into which the module is inserted can be kept narrow. This is P240739.

[0089] - 17 - contributes significantly to the stability of bearing seats in this area of ​​the rotor, as smaller slots have less impact on the structural integrity of the rotor. This results in an overall more robust and durable design, which extends the service life of both the module and the entire rotor system.

[0090] According to a further preferred embodiment of the invention, the first electrical conductor can also be formed in one piece, particularly as a busbar, and / or the second electrical conductor can also be formed in one piece, particularly as a busbar. The one-piece construction of the electrical conductors, especially in the form of busbars, offers significant advantages with regard to electrical conductivity and mechanical strength. A continuous conductor without joints minimizes electrical resistance and eliminates potential weak points that could arise from connections. This leads to improved electrical efficiency and higher load-carrying capacity of the slip ring module. In addition, manufacturing is simplified because fewer machining steps and connections are required, which reduces production costs and increases the reliability of the final product.

[0091] Furthermore, according to another advantageous embodiment of the invention, the first electrical conductor may be designed in multiple parts, with the third electrical contact section being connected to the first axial extension as a separate component, and / or the second electrical conductor may be designed in multiple parts, with the fourth electrical contact section being connected to the second axial extension as a separate component. The multi-part design of the electrical conductors allows for flexible design and adaptation of the slip ring module to specific requirements, such as the integration of separate components for the electrical contact sections. This makes it possible to optimally adapt the conductors to the geometric and functional requirements of the module, thereby, for example, simplifying assembly and improving the electrical connection.Furthermore, a separate contact section can be specifically manufactured from a material particularly suitable for contacting, which increases the module's durability and reliability. This modular design can also simplify the module's maintenance and repair by requiring only P240739.

[0092] - 18 - individual components need to be replaced. Another significant advantage of this design is that the guide slot in the rotor can be made particularly narrow. This reduces the impact on the rotor's structural integrity, contributing to increased stability and service life of the entire system. At the same time, the axially extending section of the conductor can still have a comparatively large and, for example, circular cross-section, optimizing mechanical strength and electrical conductivity without unnecessarily weakening the rotor. This combination of compact slot guidance and robust conductor design offers an ideal solution for demanding applications where both space savings and high mechanical and electrical requirements must be met.

[0093] According to a further particularly preferred embodiment of the invention, the first axial extension area and / or the second axial extension area and / or the first electrical contact section and / or the second electrical contact section and / or the third electrical contact section and / or the fourth electrical contact section may have a substantially rectangular conductor cross-section. The substantially rectangular conductor cross-section offers the advantage of better space utilization within the slip ring module. This shape allows the conductor to be positioned closer to the surrounding components, resulting in a more compact design. This is particularly advantageous in applications where space is limited and a minimal size is desired.Furthermore, the rectangular cross-section can improve heat dissipation, as a larger surface area is available for heat release, which reduces the thermal stress on the conductors and extends the module's lifespan.

[0094] Furthermore, the invention can also be further developed in such a way that the first axial extension area and / or the second axial extension area has a conductor cross-section that deviates from the rectangular shape, in particular a circular conductor cross-section. A conductor cross-section that deviates from the rectangular shape, in particular a circular one, offers advantages with regard to the mechanical strength and flexibility of the conductor. A circular cross-section can better withstand axial and radial loads, which is P240739

[0095] - 19 - The mechanical robustness of the module is improved, making it more resistant to deformation and vibration. Furthermore, this shape can facilitate handling and assembly, as a round conductor is easier to guide through confined spaces and can adapt to different geometries. This results in an overall improvement in the reliability and longevity of the slip ring module.

[0096] The object of the invention is also achieved by a rotor for an electric machine, in particular for a separately excited synchronous machine, comprising a rotor body with a first mounting slot extending axially inwards from an end face of the rotor body into the rotor body and from the outer surface of the rotor body, and a second mounting slot extending axially inwards from the end face of the rotor body into the rotor body and from the outer surface of the rotor body, and a slip ring module according to one of claims 1-6, wherein the slip ring module extends through the first mounting slot with its first radial extension area and extends through the second mounting slot with its second radial extension area.Integrating the slip ring module into the rotor by extending its radial components into the mounting slots offers significant advantages in terms of compact design and mechanical stability. This arrangement allows for particularly space-saving integration of the slip ring module, minimizing the rotor's axial installation space. This is especially beneficial in applications where installation space is limited. Furthermore, the positive-locking connection between the slip ring module and the rotor ensures high mechanical stability, increasing the overall system's service life and reducing the risk of vibrations or imbalances.

[0097] The slip ring module preferably comprises at least one electrical conductor having several bending zones. These bending zones allow for flexible and precise guidance of the conductors through the module or the mounting slots of the rotor body. The electrical conductors are advantageously shaped such that they have a large axial extent, while being particularly narrow in the circumferential or tangential direction. This shape is particularly advantageous in the area where, during assembly, a P240739

[0098] - 20 -

[0099] Axial displacement of the module occurs, particularly during the axial insertion of the module onto or into the rotor body. Due to the narrow tangential dimensions, the rotor bearing seat is only minimally interrupted by the mounting slots, which significantly improves the stability of the bearing areas and extends the bearing service life. Furthermore, avoiding unnecessarily wide slots minimizes the mechanical weakening of the rotor structure.

[0100] It can also be advantageous to further develop the invention such that the first and second mounting slots run parallel to the rotor's axis of rotation. Arranging the mounting slots parallel to the rotor's axis of rotation offers the advantage of a uniform load distribution during rotation. This leads to a reduction in vibrations and imbalances, which improves the rotor's smooth running and increases the bearing service life. Furthermore, this alignment allows for simpler and more precise assembly of the slip ring module, as the components can be aligned along a defined axis, increasing production accuracy and simplifying the assembly process.

[0101] According to a further preferred embodiment of the invention, the first and second mounting slots can be arranged at an angle to the rotor's axis of rotation. Mounting slots inclined to the axis of rotation offer the advantage of improved mechanical clamping between the slip ring module and the rotor. This arrangement can further increase the module's stability under load, as the inclined position provides additional protection against axial displacement. This is particularly advantageous in high-speed applications where high centrifugal forces occur that could dislodge the module from its position. Furthermore, this design can enable optimized power transmission to the rotor, thus improving the overall machine efficiency.

[0102] Finally, the invention can also be advantageously implemented in such a way that a first support element radially below the third electrical contacting section at least partially, preferably completely, surrounds the third contacting section and is attached to the outer surface of the rotor P240739

[0103] - 21 - a second support element is located radially below the fourth electrical contact section, at least partially, preferably completely, encompassing the fourth contact section and resting against the outer surface of the rotor. The use of support elements to fix the electrical contact sections offers significant advantages in terms of mechanical stability and securing the electrical connections during operation. These support elements ensure that the contact sections remain in position even under strong centrifugal forces or vibrations, thus increasing the reliability and service life of the electrical connection. Furthermore, the support elements protect the contact sections from mechanical damage that could be caused by external influences, thereby contributing to the longevity of the entire system.

[0104] According to a preferred embodiment of the invention, a bearing seat can be provided on the rotor in the region of the first axial extension area and the second axial extension area. Providing a bearing seat in the axial extension areas of the slip ring module offers the advantage of improved mechanical integration and stabilization of the module within the rotor. Direct bearing support in these areas ensures precise alignment and stable fixation of the slip ring module, which positively influences the overall dynamics of the rotor. This reduces the likelihood of vibrations and increases the bearing's service life, as the loads are distributed evenly. Furthermore, this design simplifies the assembly and maintenance of the module, since the axial extension areas provide a defined and stable reference plane for the bearing.

[0105] The invention will now be explained in more detail with reference to figures, without limiting the general concept of the invention.

[0106] It shows:

[0107] Figure 1 shows a first embodiment of a slip ring module and a rotor body in an unassembled state in a perspective view, P240739

[0108] - 22 -

[0109] Figure 2 shows a first embodiment of a slip ring module and a rotor body in an assembled state in an axial section view.

[0110] Figure 3 shows the electrical conductors and slip rings of the first embodiment of the slip ring module in a freestanding, perspective view.

[0111] Figure 4 shows a second embodiment of a slip ring module and a rotor body in an unassembled state in a perspective view.

[0112] Figure 5 shows the electrical conductors and slip rings of the second embodiment of the slip ring module in a freestanding, perspective view.

[0113] Figure 6 shows a third embodiment of a slip ring module and a rotor body in an unassembled state in a perspective view.

[0114] Figure 7 shows an electric machine with a slip ring module in a schematic axial section view.

[0115] Figure 7 shows a slip ring module 1 for a rotor 2 of an electric machine 3, in particular for a separately excited rotor 2 of a synchronous machine 3.

[0116] Figures 1-6 below describe in more detail three embodiments of a slip ring module 1 according to the invention. All these embodiments have in common that they comprise a base body 4 formed from an electrically insulating plastic, as well as a first slip ring 5 and a second slip ring 6 axially spaced from it by the insulating slot 35, each of which is arranged in a rotationally fixed manner on a slip ring seat 7a, 7b of the base body 4. P240739

[0117] - 23 -

[0118] The slip ring module 1 further comprises a first electrical conductor 8, which is electrically connected to the first slip ring 5 via a first electrical contacting section 17, and a second electrical conductor 9, which is electrically connected to the second slip ring 6 via a second electrical contacting section 18.

[0119] The first electrical conductor 8 has a first axial extension 10, which extends axially away from the slip ring seat 7 through the slip ring module 1, and a first radial extension 11, which adjoins the first axial extension 10 and at whose distal end 12 a third electrical contact section 13 is formed. Similarly, the second electrical conductor 9 also has a second axial extension 31, which extends axially away from the slip ring seat 7 through the slip ring module 1, and a second radial extension 14, which adjoins the second axial extension 31 and at whose distal end 15 a fourth electrical contact section 16 is formed.

[0120] The first electrical conductor 8 and the second electrical conductor 9 are completely enclosed by the plastic of the base body 4, except for the electrical contact sections 13, 16, 17, 18, and thus fixed in the base body 4.

[0121] The third contact section 13 has a first guide section 19 extending radially outwards from the first axial extension area 10, the axial cross-sectional area 20 of which is larger than its circumferential cross-sectional area 21. The fourth contact section 16 also has a second guide section 32 extending radially outwards from the second axial extension area 31, the axial cross-sectional area 23 of which is larger than its circumferential cross-sectional area 24, which can also be clearly seen in Figure 3.

[0122] The rotor 2 comprises a rotor body 30 with a first mounting slot 43 extending axially inwards from an end face 41 of the rotor body 30 into the rotor body 30 and from the outer surface 22 of the rotor body 30 radially inwards and P240739

[0123] - 24 - a second mounting slot 44 extending axially from the end face 41 of the rotor body 30 into the rotor body 30 and radially inwards from the outer surface 22 of the rotor body 30. In the assembled state, the slip ring module 1 extends through the first mounting slot 43 with its first radial extension 10 and through the second mounting slot 44 with its second radial extension 31. In the embodiments shown in Figures 1-5, the first mounting slot 43 and the second mounting slot 44 run parallel to the axis of rotation 25 of the rotor 2.

[0124] In the area of ​​the first axial extension area 11 and the second axial extension area 31, a bearing seat 33 is provided on the rotor 2.

[0125] All the illustrated embodiments also have in common that a first support element 27 surrounds the third electrical contact section 13 radially below it and rests against the outer surface 28 of the rotor 2. Similarly, a second support element 29 surrounds the fourth electrical contact section 16 radially below it and rests against the outer surface 28 of the rotor 2.

[0126] In the first embodiment of the slip ring module 1, shown in Figures 1-3, the first electrical conductor 8 and the second electrical conductor 9 are formed as a single piece, forming a busbar. Figure 3 further shows that the first axial extension area 10, the second axial extension area 31, the first electrical contact section 17, the second electrical contact section 18, the third electrical contact section 13, and the fourth electrical contact section 16 have a substantially rectangular conductor cross-section.

[0127] In a first embodiment, shown in Figure 1, the slip ring module 1 comprises two electrical conductors 8, 9 with several functional sections that are formed monolithically with the electrical conductors 8, 9 by forming the conductors 8, 9, for example by bending. These bending sections are designed such that the axial extension area 10, 31 of the electrical conductors 8, 9 is formed in each case.

[0128] - 25 -

[0129] The conductors 8, 9 extend radially (away from the center of the rotor 2) while being narrow in the tangential direction (along the circumference of the rotor 2). This narrow tangential extension of the conductors 8, 9 in the area of ​​their guide sections 19, 32, which pass through the mounting slots 43, 44, minimizes the width of the cable entry in the area of ​​the bearing seat 33 of the rotor 2. This significantly contributes to the mechanical stability of the rotor 2, as less material needs to be removed in the area of ​​the bearing seat 33 to accommodate the electrical conductors during assembly. The reduction in the slot width of the mounting slots 43, 44 increases the structural strength of the rotor 2, which has a positive effect on the service life of the bearings mounted on the bearing seat 33, as well as on the noise and vibration (NVH) characteristics of the entire system.

[0130] As can be seen particularly in Figure 3, the conductors 8, 9 were each formed by bending a busbar with a rectangular conductor cross-section. In the contact sections 17, 18 to the slip rings 5, 6, the longitudinal side of the respective conductor cross-section is oriented perpendicular to the radially extending longitudinal sides of the respective axial extension area 10, 31. These two areas of a conductor 8, 9 are thus arranged rotated by 90° relative to each other. The axial extension areas 10, 31 run, so to speak, "upright," and the longitudinal sides extend in the radial direction. Radially outside the axial extension areas 10, 31, a guide section 19, 32 adjoins each, with the conductor 8, 9 between the respective axial extension area.

[0131] 10.31 and the corresponding guide section 19,32 do not undergo any bending. Only radially outside the guide sections 19,32 is the respective conductor 8,9 bent again by 90° from a radial plane into a tangential plane in the radial extension area 11,14. Finally, the contact sections 13,16 of the conductors 8,9 are then bent from the tangential plane by 90° into an axial plane.

[0132] It is also clearly visible that the axial extension areas 10, 31 are completely enclosed by the plastic of the base body 4. The guide sections

[0133] 19.32, however, do not exhibit any insulation through the plastic material of the base body 4. P240739

[0134] - 26 -

[0135] Additionally, the slip ring module 1 is equipped with an insulating slot 35, which is subsequently machined or post-processed into the plastic material of the base body 4. The base body 4 is typically made of an electrically insulating plastic to ensure the necessary electrical isolation between the various current-carrying components. The insulating slot 35 can be introduced or post-processed after the base body 4 has been manufactured by mechanical processes such as turning or milling. This measure reduces the required creepage distance between the electrical conductors and conductive parts of the rotor 2, which makes it possible to reduce the axial size of the slip ring module 1.

[0136] In the illustrated embodiment of the first configuration, the slip ring module 1 is equipped with support elements 27, 29, which stabilize the conductor feedthrough on the rotor body 30. The support elements 27, 29 serve to mechanically stabilize the electrical conductors 8, 9 and, in particular, to protect them from centrifugal forces, especially at high rotational speeds. This fixation prevents the conductors 8, 9 from shifting or being damaged during operation, thus increasing the operational reliability of the entire slip ring module 1. Furthermore, the support elements 27, 29 provide a sealing function by preventing dirt or moisture from penetrating the sensitive area of ​​the electrical contacts. For this purpose, the support elements 27, 29 can also be pressed into the corresponding openings 34 to create a suitable seal.

[0137] In a second embodiment, shown in Figures 4-5, the slip ring module 1 does not comprise monolithic electrical conductors 8, 9, but rather a multi-part embodiment of the conductors 8, 9. In the embodiment shown in Figures 4-5, the first electrical conductor 8 is thus multi-part, and the third electrical contact section 13 is connected to the first axial extension 10 as a separate component. Similarly, the second electrical conductor 9 is also multi-part, and the fourth electrical contact section 16 is connected to the second axial extension 31 as a separate component. In the embodiment shown, the first axial extension 10 and the second axial extension 31 have P240739

[0138] - 27 - a conductor cross-section deviating from the rectangular shape, namely a circular conductor cross-section. The contact sections 13, 16, the radial extension areas 11, 14, and the guide sections 19, 32 are monolithically formed and created by bending a corresponding busbar with a rectangular conductor cross-section. Radially within the guide sections 19, 32, positive locking elements are formed that encompass the circular conductor section in the axial extension area 10, 32 of the conductors 8, 9. Furthermore, the axial extension areas 10, 32 of the conductors 8, 9 abut the end faces of the contact sections 17, 18 of the electrical conductors 8, 9, which can be clearly seen in Figure 5.

[0139] In this variant, the rotor body 30 has keyhole-shaped mounting slots 43, 44 through which the conductors 8, 9 are inserted axially into the rotor body 30 during assembly. These keyhole-shaped mounting slots 43, 44 are designed such that different sections of the electrical conductors 8, 9 are guided through different opening areas of the mounting slots 43, 44. The axial extension section 10, 31 of the conductors 8, 9 is guided through the bores 36, 37, while the guide sections 19, 32 of the conductors 8, 9 are guided through the slots extending radially outwards from the bores 36, 37 when the slip ring module 1 is inserted into the rotor body 30. This embodiment also ensures that the area of ​​the bearing seat 33 on the rotor body 30 is penetrated by only the smallest possible slots.

[0140] In a third embodiment, shown in Figure 6, the slip ring module 1 comprises threaded axial extension areas 10, 31 of the conductors 8, 9 and correspondingly shaped mounting slots 43, 44. The first mounting slot 43 and the second mounting slot 44 thus project at an angle 26 to the axis of rotation 25 of the rotor 2. This threaded design allows the slip ring module 1 to be screwed into the rotor 2 during the assembly process and simultaneously pushed axially into position. This ensures a particularly strong and secure connection between the slip ring module 1 and the rotor 2, further improving the mechanical stability of the entire system. This embodiment is particularly suitable for applications involving high rotational speeds and associated centrifugal forces. P240739

[0141] - 28 - The threaded guide of the slip ring module 1 prevents the slip ring module 1 from loosening or shifting during operation.

[0142] Furthermore, a combination of keyhole-shaped mounting slots 43, 44, as shown in Figure 4, and threaded mounting slots 43, 44, as shown in Figure 6, can also be provided. This combination enables particularly flexible and robust mounting of the slip ring module 1 in the rotor 2. The invention is not limited to the embodiments shown in the figures. The foregoing description is therefore not to be considered limiting, but rather explanatory. The following claims are to be understood as meaning that a named feature is present in at least one embodiment of the invention. This does not preclude the presence of further features. Insofar as the claims and the foregoing description define 'first' and 'second' features, this designation serves to distinguish between two similar features without establishing a hierarchy.

[0143] P240739

[0144] - 29 -

[0145] List of reference signs

[0146] 1 slip ring module

[0147] 2 Rotor

[0148] 3 electric machine

[0149] 4 basic shapes

[0150] 5 slip ring

[0151] 6 slip ring

[0152] 7 Slip ring seat

[0153] 8 ladders

[0154] 9 ladders

[0155] 10 Scope

[0156] 11 Scope

[0157] 12 End

[0158] 13 Contact section

[0159] 14 Scope

[0160] 15 End

[0161] 16 Contact section

[0162] 17 Contact section

[0163] 18 Contact section

[0164] 19 Leadership section

[0165] 20 Cross-sectional area

[0166] 21 Cross-sectional area

[0167] 22 Surface area

[0168] 23 Cross-sectional area

[0169] 24 Cross-sectional area

[0170] 25 Rotation axis

[0171] 26 angles

[0172] 27 Support element

[0173] 28 Surface area

[0174] 29 Support element

[0175] 30 rotor bodies

[0176] 31 Scope

[0177] 32 Management section P240739

[0178] 33 bearing seat

[0179] 34 Opening

[0180] 35 Insulation slots

[0181] 36 bore 37 bore

[0182] 41 Front

[0183] 43 Mounting slot 44 Mounting slot

Claims

P240739 - 31 - Claims 1. Slip ring module (1) for a rotor (2) of an electric machine (3), in particular for a separately excited rotor (2) of a synchronous machine (3), comprising: • a base body (4) formed from an electrically insulating plastic, as well as • a first slip ring (5) and • a second slip ring (6) which are each arranged in a rotationally fixed manner on a slip ring seat (7) of the base body (4), as well as • a first electrical conductor (8) which is electrically connected to the first slip ring (5) via a first electrical contact section (17), and • a second electrical conductor (9) which is electrically connected to the second slip ring (6) via a second electrical contact section (18), • wherein the first electrical conductor (8) has a first axial extension area (10) which extends axially away from the slip ring seat (7) through the slip ring module (1) and has a first radial extension area (11) which adjoins the first axial extension area (10) and at whose distal end (12) a third electrical contacting section (13) is formed • and the second electrical conductor (9) has a second axial extension area (31) extending axially away from the slip ring seat (7) through the slip ring module (1), and a second radial extension area (14) extending from the second axial P240739 - 32 - extension area (31) adjoins and a fourth electrical contacting section (16) is formed at its distal end (15), characterized in that the first electrical conductor (8) and the second electrical conductor (9) are at least partially, preferably completely, enclosed by the plastic of the base body (4) and thus fixed in the base body (4), except for the electrical contacting sections (13, 16, 17, 18).

2. Slip ring module (1 ) according to claim 1 , characterized in that the third contacting section (13) has a first guide section (19) extending radially outwards from the first axial extension area (10), the axial cross-sectional area (20) of which is larger than its circumferential cross-sectional area (21 ) and / or the fourth contacting section (16) has a second guide section (32) extending radially outwards from the second axial extension area (31 ), the axial cross-sectional area (23) of which is larger than its circumferential cross-sectional area (24).

3. Slip ring module (1 ) according to claim 1 or 2, characterized in that the first electrical conductor (8) is formed in one piece, in particular as a busbar and / or the second electrical conductor (9) is formed in one piece, in particular as a busbar.

4. Slip ring module (1) according to one of the preceding claims, characterized in that the first electrical conductor (8) is designed in multiple parts and the third electrical contacting section (13) is connected as a separate component to the first axial extension area (10) and / or P240739 - 33 - the second electrical conductor (9) is designed in multiple parts and the fourth electrical contacting section (16) is connected as a separate component to the second axial extension area (31 ).

5. Slip ring module (1 ) according to one of the preceding claims, characterized in that the first axial extension area (10) and / or the second axial extension area (31 ) and / or the first electrical contacting section (17) and / or the second electrical contacting section (18) and / or the third electrical contacting section (13) and / or the fourth electrical contacting section (16) have / have a substantially rectangular conductor cross-section.

6. Slip ring module (1 ) according to one of the preceding claims, characterized in that the first axial extension area (10) and / or the second axial extension area (31 ) have a conductor cross-section that deviates from the rectangular shape, in particular a circular conductor cross-section.

7. Rotor (2) for an electric machine (3), in particular for a separately excited synchronous machine, comprising - a rotor body (30) with - a first mounting slot extending axially from an end face (41) of the rotor body (30) into the rotor body (30) and radially inwards from the outer surface (22) of the rotor body (30). (43) - a second mounting slot extending axially from the end face (41) of the rotor body (30) into the rotor body (30) and radially inwards from the outer surface (22) of the rotor body (30). (44) as well as P240739 - 34 - a slip ring module (1 ) according to one of the preceding claims, - wherein the slip ring module (1 ) with its first radial extension area (11 ) extends through the first mounting slot (43) and with its second radial extension area (14) extends through the second mounting slot (44).

8. Rotor (2) according to claim 7, characterized in that the first mounting slot (43) and the second mounting slot (44) run parallel to the axis of rotation (25) of the rotor (2).

9. Rotor (2) according to claim 7, characterized in that the first mounting slot (43) and the second mounting slot (44) extend at an angle (26) to the axis of rotation (25) of the rotor (2).

10. Rotor (2) according to claim 7 or 8, characterized in that radially below the third electrical contacting section (13) a first support element (27) surrounds the third contacting section (13) at least partially, preferably completely, and bears against the outer lateral surface (22) of the rotor (2) and / or radially below the fourth electrical contacting section (16) a second support element (29) surrounds the fourth contacting section (16) at least partially, preferably completely, and bears against the outer lateral surface (22) of the rotor (2).

11. Rotor (2) according to one of claims 7 to 9, characterized in that P240739 - 35 - in the area of ​​the first axial extension area (11 ) and the second axial extension area (31 ) a bearing seat (33) is provided on the rotor (2).

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