Rotor for an axial flux machine, in particular for a motor vehicle, method for manufacturing such a rotor and axial flux machine

Abstract

The invention relates to a rotor (10) for an axial flux machine, with permanent magnets (12) which are held on a carrier (18) which is formed from a fiber-reinforced plastic, which is formed from a matrix (M) formed from a first material and reinforcing fibers (F) formed from a second material different from the first material embedded in the matrix (M), wherein the reinforcing fibers (F) are provided with a coating (BS) formed from a third material different from the first material and from the second material, by means of which the reinforcing fibers (F) are electrically insulated from each other and from the permanent magnets (12).

Description

[0001] The invention relates to a rotor for an axial flux machine, in particular for a motor vehicle, according to the preamble of claim 1. The invention further relates to a method for manufacturing such a rotor. The invention also relates to an axial flux machine for a motor vehicle.

[0002] DE 10 2021 105 499 B4 discloses a rotor for an axial flux machine. CN 107979256 A1 discloses an electrical machine as known. DE 10 2019 216 844 A1 discloses an axial flux machine. Furthermore, EP 3 506 463 A1 discloses an integrated flywheel energy storage device.

[0003] The object of the present invention is to provide a rotor for an axial flux machine, a method for manufacturing such a rotor and an axial flux machine, so that a particularly efficient operation of the axial flux machine can be realized.

[0004] This problem is solved by a rotor with the features of claim 1, by a method with the features of claim 9, and by an axial flux machine with the features of claim 10. Advantageous embodiments with expedient further developments of the invention are specified in the remaining claims.

[0005] A first aspect of the invention relates to a rotor for an axial flux machine, in particular for a motor vehicle. This means that the motor vehicle, preferably designed as a motor vehicle, especially a passenger car, and also simply referred to as a vehicle, in its fully manufactured state comprises the axial flux machine and can be driven electrically by means of the axial flux machine, in particular purely electrically. The axial flux machine is an electric machine and is also referred to as an axial flux motor (AFM). In its fully manufactured state, the axial flux machine comprises the rotor and, for example, a stator by means of which the rotor can be driven and thereby rotated about a machine axis of rotation relative to the stator. The rotor, whose axial direction coincides with the machine axis of rotation, has permanent magnets, which are also simply referred to as magnets.Furthermore, the rotor, whose radial direction is perpendicular to the axial direction of the rotor and thus perpendicular to the machine's axis of rotation, has a support, which is formed separately from the permanent magnets and is also referred to as a support structure. The permanent magnets are held on the support, in particular in such a way that relative movements between the respective permanent magnets and the support are prevented. The support is formed, in particular entirely and / or exclusively, from a fiber-reinforced plastic, which is also referred to as a fiber-reinforced plastic. The fiber-reinforced plastic is formed, in particular exclusively and / or entirely, from a matrix and reinforcing fibers, also simply referred to as fibers, embedded in the matrix. The matrix is ​​formed, in particular entirely and / or exclusively, from a first material.The respective reinforcing fiber is formed, in particular completely and / or exclusively, from a second material different from the first. It is conceivable that the reinforcing fibers are long fibers, so that the matrix and the reinforcing fibers embedded in the matrix form, for example, a laser fiber composite. Furthermore, it is possible that the reinforcing fibers are short fibers, so that the matrix and the reinforcing fibers embedded in the matrix form a short-fiber composite in which, for example, the reinforcing fibers are arranged randomly and are therefore non-directional fibers.

[0006] To achieve particularly low-loss and therefore particularly efficient operation of the axial flux machine and thus of the motor vehicle as a whole, the invention provides that the reinforcing fibers are coated. The coating is formed, in particular exclusively and / or completely, from a third material that differs from the first and second materials. The coating electrically insulates the reinforcing fibers from one another. Advantageously, the third material has a high specific electrical resistance. Furthermore, the coating electrically insulates the reinforcing fibers from the permanent magnets.In other words, the coating electrically insulates the reinforcing fibers from each other, i.e., from one another, and from the permanent magnets. For this purpose, the third material, and thus the coating, is designed as a non-conductor. Within the scope of this disclosure, a non-conductor is understood to be a material whose electrical conductivity is less than 10. -8 S · cm -1 This allows unwanted eddy current paths between the individual reinforcing fibers and between the respective reinforcing fiber and the respective permanent magnet to be avoided, thus enabling a particularly efficient and therefore cost-effective operation of the axial flux machine.

[0007] In particular, it is conceivable that the reinforcing fibers are continuous fibers.

[0008] In order to electrically insulate the reinforcing fibers from each other and from the permanent magnet particularly effectively and efficiently, and consequently to achieve particularly efficient operation of the axial flux machine, one embodiment of the invention provides that the third material is and comprises a silicate. Alternatively or additionally, the third material is or comprises silicon (Si). Alternatively or additionally, the third material is or comprises a ceramic. For example, the third material can be or comprise a silicon carbide such as SiC3. For example, the third material can be or comprise a silicate such as SiO2.

[0009] Another embodiment is characterized by the fact that the coating is a plasma coating. This allows the reinforcing fibers to be electrically insulated particularly advantageously from each other and from the permanent magnets, thus enabling particularly efficient operation.

[0010] In order to achieve particularly efficient operation of the electric machine (axial flux machine), a further embodiment of the invention provides that the coating is bonded to the matrix and / or the reinforcing fibers, in particular exclusively, by adhesion. This allows for a strong bond between the matrix and the reinforcing fibers embedded in the matrix and coated with the coating.

[0011] Since the coating is formed from the third material, this third material is also referred to as the coating material. Preferably, the coating material is selected such that a particularly advantageous adhesion between the matrix and the coating material can be achieved, thereby ensuring a particularly strong bond between the composite. Furthermore, it is preferably provided that the coating has a layer thickness that is advantageously small, for example, relative to the respective reinforcing fiber. For example, the layer thickness is only a few nanometers. In particular, it is conceivable that the layer thickness is at most 100 nanometers, and more specifically, at most 50 nanometers. It is also conceivable that the layer thickness is at most 10 nanometers, and more specifically, less than 10 nanometers.This allows for particularly advantageous mechanical properties of the aforementioned composite to be realized, enabling a particularly advantageous, efficient operation of the axial flux machine.

[0012] To achieve a particularly advantageous and efficient operation of the axial flux machine, a further embodiment of the invention provides that the second material, from which the reinforcing fibers are formed, is an electrically conductive material. The reinforcing fibers themselves, that is, considered on their own, are thus electrically conductive, but the reinforcing fibers are electrically insulated from each other and from the permanent magnets by means of the coating.

[0013] It has proven particularly advantageous if the second material is carbon, so that preferably the reinforcing fibers are carbon fibers. Thus, the fiber composite material is a carbon fiber reinforced plastic, which allows for particularly advantageous mechanical properties of the substrate.

[0014] Finally, it has proven particularly advantageous if the carrier has a ring, also referred to as an outer ring, on which the permanent magnets are supported at least indirectly, and in particular directly, in the radial direction of the rotor. This allows even particularly high centrifugal forces acting on the permanent magnets, which result, for example, from high rotational speeds at which the rotor turns around the machine's axis of rotation relative to the stator, to be transferred from the permanent magnets to the ring and thus absorbed by the ring, enabling particularly efficient operation of the axial flux machine.

[0015] A second aspect of the invention relates to a method for manufacturing a rotor, particularly according to the first aspect of the invention, for an axial flux machine, especially of a motor vehicle. In a method according to the second aspect of the invention, a rotor support is manufactured from a fiber-reinforced plastic, which is made from a matrix formed from a first material and reinforcing fibers formed from a second material different from the first material and embedded in the matrix.

[0016] In this process, permanent magnets, also simply referred to as magnets, are provided separately from the carrier and are fixed at least indirectly to the carrier, in particular in such a way that relative movements between the respective permanent magnets and the carrier are prevented or are prevented.

[0017] To achieve particularly efficient operation of the axial flux machine, the method according to the second aspect of the invention provides that the reinforcing fibers are coated with a third material, different from the first and second materials, by means of which the reinforcing fibers are electrically insulated from each other and from the permanent magnets. Advantages and advantageous embodiments of the first aspect of the invention are to be considered as advantages and advantageous embodiments of the second aspect of the invention, and vice versa.

[0018] For example, in the method according to the second aspect of the invention, a coating process is carried out in which the reinforcing fibers are provided with the third material, also referred to as the coating material, and thus with the coating. In the coating process, for example, the third material is applied to the reinforcing fibers in a liquid state. It is conceivable that in the coating process the third material is applied to each individual reinforcing fiber, so that, for example, the reinforcing fibers are individually provided with the coating material.Furthermore, it is conceivable that in the coating process, individual reinforcing fibers form a fiber bundle or roving, whereby in the coating process each fiber bundle or roving is, for example, individually coated with the coating material, so that when the respective fiber bundle or roving is coated with the third material, the respective reinforcing fibers forming the respective fiber bundle or roving are coated with the coating material, particularly simultaneously. The coating process, also referred to as a coating process, can thus be carried out for individual fibers, for the rovings, for filament yarn, or for fiber bundles.

[0019] For example, the first material from which the matrix is ​​formed is or comprises an epoxy resin and / or a polyester resin and / or vinyl ester and / or polyamide. Since the matrix is ​​formed from the first material, the first material is also referred to as the matrix material. For example, in this process, the reinforcing fibers, which are coated with the matrix material, particularly impregnated, are laid down using a winding process. Here, for example, the reinforcing fibers impregnated with the matrix material form fiber bundles or fiber rovings, which are laid down using the aforementioned winding process. The winding process can be a conventional winding process, an additive translational winding technique, or a robot-guided fiber placement.Impregnation, in which reinforcing fibers are coated with the matrix material, occurs, for example, through the soaking of the reinforcing fibers, particularly fiber bundles or rovings formed by the reinforcing fibers. Alternatively, pre-impregnated rovings, also known as bundles, fiber bundles, or fiber rovings, can be used; these are also referred to as prepregs.

[0020] In this process, for example, an assembly is carried out in which the permanent magnets are fixed and thus mounted to the carrier, in particular to the ring. During assembly, the ring is stretched, in particular outwards in the radial direction of the rotor, and the stretched ring is mounted onto the permanent magnets, in particular onto a magnetic cassette formed by the permanent magnets. To avoid possible damage resulting from the stretching of the ring, it is possible to directly wind the permanent magnets, in particular the magnetic cassette formed by the permanent magnets, with reinforcing fibers. For this purpose, the reinforcing fibers, in particular as prepreg or wet-impregnated bundles, are laid onto the permanent magnets, in particular onto the magnetic cassette, under tension.

[0021] The invention allows at least the following advantages to be realized: - Reduction of eddy current losses in the rotor due to an alternating magnetic field in the operation of an axial flux machine, which is used, for example, as an electric traction machine. - No induction of additional eddy currents in the magnets through electrical connection of the reinforcing fibers to the permanent magnets - Contact corrosion between the carrier, especially the ring, and the magnets, i.e., between the magnets and the first material, is prevented. - Corrosion of magnetic surfaces due to environmental conditions is prevented. - Improved magnetic performance due to reduced heat generation resulting from decreased eddy current losses in the rotor - Cost reduction due to a reduced proportion of rare earth elements in the permanent magnets, in particular through a reduction in coercive field strength due to lower operating temperatures of the axial flux machine.

[0022] For example, the respective permanent magnet is laminated, that is, designed as a laminated magnet, in particular such that the respective magnet segments of the respective permanent magnet are arranged successively and thus one on top of the other in the radial direction of the rotor, wherein, for example, the magnet segments of the respective permanent magnet are designed separately from one another and connected to each other. For example, the respective magnet segments of the respective permanent magnet are bonded together by means of an adhesive and thereby connected to each other.

[0023] For example, the permanent magnets are passivated permanent magnets. Preferably, the adhesive is an electrically non-conductive adhesive and thus preferably a non-conductor.

[0024] The invention is based in particular on the following findings and considerations: The rotor is, for example, a disc rotor or a rotor disk. In other words, the rotor is, for example, disk-shaped. For example, the axial flux machine in its fully manufactured state has a double-rotor arrangement or a double-stator arrangement. In order to achieve a particularly high torque and power density, the axial flux machine in its fully manufactured state has, for example, a double-rotor arrangement which includes rotor disks, wherein, for example, the rotor can be a first of the rotor disks. The respective rotor disk includes, for example, the carrier and the permanent magnets, which, for example, form the aforementioned magnet cassette.

[0025] The disc-shaped design of the rotor enables, for example, novel drive concepts for motor vehicles. Due to space constraints, the outer diameter of the rotor is typically relatively limited, especially for coaxial applications in passenger cars. Therefore, and for efficiency reasons, an increase in the efficiency of the axial flux machine is sought compared to conventional solutions. In axial flux machines, laminated permanent magnets are currently pressed into a magnet cassette made of SMC (Sheet Molding Compound), where SMC is, for example, the aforementioned fiber-reinforced plastic that comprises the matrix and the reinforcing fibers, such as carbon fibers. This lamination of the permanent magnets can advantageously minimize eddy current losses occurring in the magnets. The carbon fibers themselves are electrically conductive, which can lead to eddy currents within the axial flux machine as a result of an alternating magnetic field.These eddy currents occur within the carbon material itself. Furthermore, electrical connections between individual magnet segments via the carbon fibers can also induce eddy current paths within the magnet (contact resistance). This can lead to a significant increase in rotor losses, which is detrimental to both efficiency and magnetic performance (higher magnet temperature leads to power reduction due to lower remanence and retarding field stability). Power reduction means that the maximum power output of the electric machine is deliberately limited and thereby reduced compared to a state where power reduction does not occur.Electrical contact between the carbon fibers and the permanent magnets, or the magnetic material from which the permanent magnets are made, can lead to contact corrosion via an electrolyte, causing the magnets to corrode. Similarly, fluctuating temperatures during operation of the axial flux machine, as well as environmental influences, can cause corrosion on the magnet surfaces, potentially leading to failure of the axial flux machine over its lifetime. The invention now makes it possible to reduce eddy current losses in the magnets compared to conventional solutions, thereby increasing the efficiency of the axial flux machine.

[0026] To absorb the high centrifugal forces of the magnets resulting from high rotor speeds, for example, the ring is mounted with an interference fit or preload onto the permanent magnets, particularly the magnet cassette. Carbon fibers are advantageous because they exhibit high strength and stiffness combined with low density. To achieve advantageous mechanical properties of the carrier, especially the ring, the reinforcing fibers are preferably designed as continuous fibers.

[0027] It is conceivable that the support has a first support element formed from the fiber-reinforced plastic. Furthermore, it is possible that the support has a second support element, which is, for example, a stack of sheets formed from a sheet also known as electrical steel or designed as such. The support elements are connected to one another, in particular in such a way that relative movement between the support elements is prevented.

[0028] Preferably, the second material from which the matrix is ​​formed is a reactive resin.

[0029] Another insight underlying the invention is that, if no countermeasure is taken, an electrical contact, particularly a direct one, can occur between the carbon fibers and the magnetic material from which the permanent magnets are formed. In this case, the carbon from which the reinforcing fibers are formed acts as a noble cathode, and the magnetic material acts as a less noble anode, which can cause the permanent magnets to corrode. This can now be avoided in the invention by coating the reinforcing fibers.

[0030] The coating is designed to shield the individual reinforcing fibers from each other and from their surroundings, providing electrical insulation. Preferably, the coating thickness, also referred to as the layer thickness, is small relative to the thickness of the individual reinforcing fibers, for example, in the range of a few nanometers to a few micrometers. This ensures advantageous stability of the composite. Furthermore, it is preferably designed that the coating can withstand significantly higher temperatures without damage than those encountered in a subsequent process step, such as during the curing of the matrix material and / or during operation of the axial flux machine.Thus, for example, the matrix, i.e., the matrix material, can harden, while the coating and the associated electrical insulation of the reinforcing fibers caused by the coating remain unaffected.

[0031] A further advantage achievable with the invention is that, compared to conventional solutions, inhomogeneous electrical conductivity is significantly reduced, leading to reduced losses in the rotor. Within the magnet cassette, eddy current paths can be reduced compared to conventional solutions, since eddy current paths can only propagate in the individual, electrically isolated reinforcing fibers. The induction of additional eddy currents in the permanent magnets through an electrical connection of the reinforcing fibers to the individual magnet segments can be avoided.

[0032] In particular, the invention can be used for SMC, TSIM (Thermoset Injection Molding) or other fiber fabrics. In the coating process, the reinforcing fibers can be provided with the coating, for example, by conventional application of the third material to the reinforcing fibers, or an immersion bath is used by means of which the reinforcing fibers are provided with the third material and thus with the coating, in particular by immersing the reinforcing fibers in the immersion bath.

[0033] The carrier can advantageously ensure that the permanent magnets are held on and, for example, in the carrier, particularly on and, for example, in the magnet cassette (also simply referred to as a cassette), both during operation of the axial flux machine, in which the rotor rotates around the machine's axis of rotation relative to the stator, and during standstill of the rotor, which does not rotate around the machine's axis of rotation relative to the stator. To manufacture the carrier, in particular the ring, the aforementioned rovings, also referred to as bundles, fiber bundles, or fiber rovings, are wound onto a tube to create or maintain a specific geometry of the carrier, in particular the ring, while a curing process takes place in which the matrix material hardens.After the matrix material, and thus the fiber-reinforced plastic (also known simply as fiber composite), has cured, rings of a desired thickness are cut from the tube to produce the respective rotor or carrier. In another method, the rings are wound in a mold with a specific geometry, particularly a desired carrier thickness. This has the advantage that the fibers are not separated when the rings are cut from the tube, meaning they remain continuous, allowing the carrier to withstand particularly high radial loads. To prevent potential damage, especially that caused by stretching of the carrier, particularly the ring, especially during the mounting of permanent magnets to the ring and vice versa, it is possible to directly wind the permanent magnets that, for example, form the aforementioned magnet cassette.For this purpose, reinforcing fibers, such as prepreg or wet-impregnated rovings, are laid on the magnet cassette with pretension. Using a specific winding technique, for example, to wind the rovings onto the aforementioned tube, different fiber orientations of the reinforcing fibers, particularly within the matrix, can be created as required. Typically, the reinforcing fibers, also simply referred to as fibers, are laid predominantly circumferentially around the tube, especially at a 90-degree angle, to best absorb the centrifugal forces of the magnets during operation. With conventional winding, fiber layers of exactly 90 degrees cannot be achieved. Layers in the composite have an orientation of approximately 89 degrees.

[0034] The surfaces of the carrier, especially after its separation from the tube, require post-processing. Grinding processes are used for this purpose. One advantage that can be achieved by directly winding the permanent magnets with the reinforcing fibers, particularly those that are impregnated, is that this allows for advantageous adjustment of the carrier geometry, and the reinforcing fibers can, for example, be laid at a 90-degree angle to effectively absorb radial loads.

[0035] Further advantages, features, and details of the invention will become apparent from the following description of preferred embodiments and from the drawings. The features and combinations of features mentioned above in the description, as well as those mentioned below in the figure description and / or shown in the figures alone, can be used not only in the combinations specified, but also in other combinations or individually, without departing from the scope of the invention.

[0036] The drawing shows in: Fig. 1 a schematic front view of a rotor for an axial flux machine, in particular of a motor vehicle; Fig. 2 a schematic and enlarged representation of a in Fig. 1. Area of ​​the rotor designated B; Fig. 3. Partially a schematic sectional view of a first embodiment of a rotor support; Fig. 4. Partially a schematic sectional view of a second embodiment of the carrier; Fig. 5. A schematic cross-sectional view of a reinforcing fiber of a fiber-reinforced plastic from which the carrier is formed; and Fig. 6 A schematic representation to illustrate a method for manufacturing the rotor.

[0037] In the figures, identical or functionally equivalent elements are provided with the same reference symbols.

[0038] Fig. Figure 1 shows a schematic front view of a rotor 10 for an axial flux machine, also known as an axial flux motor, of a motor vehicle, also referred to simply as a vehicle. The axial flux machine is an electric machine and, in its fully manufactured state, comprises the rotor 10 and a stator by means of which the rotor 10 can be driven and thus rotated about a machine axis of rotation relative to the stator. For example, the rotor 10 is disk-shaped and thus a rotor disk. It is conceivable that the axial flux machine has a complete rotor, which can be driven by means of the stator and thus rotated about the machine axis of rotation relative to the stator. For example, the axial flux machine can provide drive torques via its complete rotor for, in particular, purely electric propulsion of the motor vehicle. The complete rotor includes, for example, the rotor 10, in particular as the first rotor disk.Furthermore, it is conceivable that the complete rotor has at least or exactly two rotor disks, namely the aforementioned first rotor disk and a second rotor disk. It is conceivable that the rotor disks, which are also referred to as rotor elements, are at least partially spaced apart from each other in the axial direction of the axial flux machine and thus of the respective rotor disk. It is conceivable that at least a portion of the stator is arranged between the rotor disks in the axial direction of the axial flux machine, whose axial direction coincides with the machine's axis of rotation, in particular such that the first rotor disk, viewed in the axial direction of the axial flux machine towards the second rotor disk, and the second rotor disk, viewed in the axial direction of the axial flux machine towards the first rotor disk, are each at least partially overlapped and thus covered by the aforementioned portion of the stator.It is conceivable that the rotor disks are designed separately from one another and, in particular, permanently and rotationally fixed to each other. As described above, rotor 10 can be the first rotor disk, and the preceding and following explanations regarding the first rotor disk can readily be applied to the second rotor disk and vice versa.

[0039] The rotor 10 has permanent magnets 12, which, for example, form a magnet cassette 14 of the rotor 10. Each permanent magnet 12 is also simply referred to as a magnet.

[0040] In Fig. 1 is illustrated with B as a region of the rotor 10, where the region B is in Fig. Figure 2 is shown enlarged. It looks particularly good. Fig. Figure 2 shows that, for example, the respective permanent magnet 12 has a segmented structure. This means that the respective permanent magnet 12 has, for example, individual magnet segments 16, wherein the respective magnet segments 16 of the respective permanent magnet 12 are arranged successively and one above the other in the radial direction of the rotor 10, whose axial direction coincides with the machine's axis of rotation. It is conceivable that the respective magnet segments 16 of the respective permanent magnet 12 are formed separately from one another and connected to each other, in particular by means of an adhesive. The radial direction of the rotor 10 is perpendicular to the axial direction of the rotor 10 and thus perpendicular to the machine's axis of rotation.The rotor 10 also has a carrier 18, separate from the permanent magnets 12, on which the permanent magnets 12 are held and thereby fixed, in particular in such a way that relative movements between the respective permanent magnet 12 and the carrier 18 are prevented. For example, the respective magnet segment 16 and thus the respective permanent magnet 12 is made of a magnetic material, which is preferably a metallic material.

[0041] The support 18, for example, has a first support element 19 and a second support element not shown in the figures. The support 18, and in particular the first support element 19, is made of a fiber-reinforced plastic composite. For example, the second support element is connected to the first support element 19, in particular such that relative movements between the first support element 19 and the second support element are prevented. In particular, the second support element is a stack of sheets made of sheet metal, in particular electrical steel.

[0042] While Fig. Figure 3 shows a schematic sectional view of a first embodiment of the support 18, in particular of the support element 19. Fig. 4. Partially a schematic sectional view of a second embodiment of the support 18, in particular of the support element 19. From Fig. Figures 2 to 4 clearly show that the fiber-reinforced plastic is formed, in particular entirely, from a matrix M and reinforcing fibers F embedded in the matrix M, the reinforcing fibers F also being referred to simply as fibers. The matrix M is formed, in particular entirely and / or exclusively, from a first material, which is also referred to as the matrix material. In particular, the matrix material is a material different from the magnetic material. The reinforcing fibers F are formed, in particular exclusively and / or entirely, from a second material different from the first material, which is also referred to as the fiber material. In the first embodiment and also in the second embodiment, the fiber-reinforced plastic is a carbon fiber reinforced plastic (CFRP), so the fiber material is carbon.Thus, the reinforcing fibers F are carbon fibers, also known as carbon fibers. The reinforcing fibers F themselves, that is, considered on their own, are therefore electrically conductive. Preferably, the matrix material is a plastic. For example, the matrix material is a reactive resin.

[0043] At the in Fig. In the first embodiment of the carrier 18 shown in Figure 3, the reinforcing fibers F are long fibers, such that the matrix M and the reinforcing fibers F embedded in the matrix M form a long-fiber composite. In the embodiment shown in Fig. In the second embodiment of the carrier 18 shown in Figure 4, the reinforcing fibers F are short fibers, so that the matrix M and the reinforcing fibers F embedded in the matrix M form a short fiber composite.

[0044] Looks especially good Fig. It can be seen that the support element 19, and thus the support 18, has a support ring 20, preferably an inner, middle, and most preferably a central one, as a first ring, on which the permanent magnets 12 are supported at least indirectly, and in particular directly, in the radial direction of the rotor 10. Furthermore, the support element 19, and thus the support 18, has an outer ring 22 as a second ring, on which the permanent magnets 12 are supported at least indirectly, and in particular directly, in the radial direction of the rotor 10. The rings are thus formed from the fiber-reinforced plastic. In particular, the rings are arranged coaxially with each other. It can be seen that the first ring, also referred to as the inner ring, and thus the support ring 20, has an opening 24, preferably a middle and most preferably a central one, designed as a through-opening.For example, at least a section of the rotor shaft of the overall rotor can be arranged or is arranged in the opening 24, such that, for example, the rotor shaft, which is formed separately from the support 18 and is also simply referred to as the shaft, can be connected or is connected to the support 18 in a rotationally fixed manner, particularly over its length. In particular, the overall rotor can provide the drive torques via the rotor shaft.

[0045] The support element 19, and thus the support 18, also has intermediate webs 26, which are arranged between the permanent magnets 12 in the circumferential direction of the rotor 10, and thus around the machine's axis of rotation, such that the permanent magnets 12 and the intermediate webs 26 alternate along the circumferential direction of the rotor 10. The intermediate webs 26 are also made of the fiber-reinforced plastic. It is further evident that the intermediate webs 26, also simply referred to as webs, are arranged between the rings, particularly in the radial direction of the rotor 10, with the rings being connected to each other via the webs.

[0046] In order to achieve particularly efficient operation of the axial flux machine, the reinforcing fibers F, in particular at least predominantly and thus at least more than half or even completely, that is, entirely, are provided with a coating BS, which is formed from a third material different from the first material, the second material, and preferably also from the magnetic material. The coating BS electrically insulates the reinforcing fibers F from each other and from the permanent magnets 12. This is evident from... Fig. 3 and Fig. 4 is that the composite thus also includes the coating BS, so that the reinforcing fibers F provided with the coating BS and thus coated are embedded in the matrix M.

[0047] Fig. Figure 5 shows a section of a schematic cross-sectional view of one of the reinforcing fibers F. It looks particularly good from Fig. The BS coating is recognizable in 5. Fig. 5 shown reinforcing fiber F.

[0048] In Fig. Figure 6 schematically illustrates a method for manufacturing the rotor 10. In particular, the method comprises a Fig.Figure 6 schematically illustrates the coating process, which is also referred to as the coating method. In the coating method, the reinforcing fibers F are provided with the third material, also referred to as the coating material, and thus with the coating BS, in particular, for example, by applying the coating material in a liquid state to the reinforcing fibers F, especially by spraying it on. For this purpose, for example, a supply device 28 is provided by means of which the coating material is sprayed or dispensed, and in particular sprayed or dispensed directly against the reinforcing fibers F, thereby providing the reinforcing fibers F with the coating material and thus with the coating BS. Reference symbol list 10 Rotor 12 permanent magnets 14 magnetic cassettes 16 magnetic segments 18 carriers 19 first support element 20 support ring 22 Outer ring 24-hour opening 26 intermediate walkways 28 Provisioning facility Area B BS coating F Reinforcing fiber M Matrix QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] DE 10 2021 105 499 B4

[0002] CN 107979256 A1

[0002] DE 10 2019 216 844 A1

[0002] EP 3 506 463 A1

[0002]

Images