Rotor for an axial flux machine, in particular of a motor vehicle, as well as 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) of the rotor (10) formed separately from the permanent magnets (12), wherein at least one layer (S) is arranged between a respective sub-area (TB1) of the respective permanent magnet (12) and a respective sub-area (TB2) of the carrier (18), in which a filler (F) mechanically stabilizing the respective layer (S) is contained, consisting of particles (P) formed as solids.

Description

[0001] The invention relates to a rotor for an axial flux machine, in particular of a motor vehicle, according to the preamble of claim 1. Furthermore, the invention relates to an axial flux machine for a motor vehicle, comprising at least one such rotor.

[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 create a rotor for an axial flux machine, in particular for a motor vehicle, as well as an axial flux machine, so that a particularly advantageous operation of the axial flux machine can be realized.

[0004] This problem is solved by a rotor with the features of claim 1 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 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 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 structure separate from the permanent magnets, which is also referred to as the support device or support structure. The permanent magnets are held on the support structure, in particular in such a way that relative movements between the respective permanent magnet and the support structure are prevented. The support structure can, for example, be made entirely or partially of a fiber-reinforced plastic, which can be made entirely and / or exclusively of a matrix and reinforcing fibers embedded in the matrix, also simply referred to as fibers. The matrix is ​​made entirely and / or exclusively of a plastic.Alternatively or additionally, it is conceivable that the support could be at least partially made of a metallic material such as sheet metal, particularly electrical steel. In other words, it is conceivable that the support has, for example, a first support element made of the aforementioned fiber-reinforced plastic. Furthermore, it is conceivable that the support has a second support element, which is, for example, a stack of sheets made of the aforementioned sheet metal, also known as electrical steel. The support elements are connected to each other.

[0006] For example, fiber-reinforced plastic is a fiber-reinforced plastic, so that at least some of the reinforcing fibers, in particular the or all of the reinforcing fibers, are, for example, carbon fibers.

[0007] In order to achieve a particularly advantageous operation of the axial flux machine and thus of the motor vehicle as a whole, the invention provides that at least one layer is arranged between each respective sub-region of the respective permanent magnet and each respective sub-region of the support, in which a filler material consisting of solid particles, which mechanically stabilizes the layer, is incorporated. In particular, it is provided that the respective sub-region of the respective permanent magnet and the respective sub-region of the support are supported against each other by the layer arranged between the sub-regions, in particular such that no air gap is arranged between the respective sub-region and the layer.In particular, it is conceivable that the respective section of the permanent magnet and / or the respective section of the substrate is directly supported by the layer and thus in direct contact with it. The layer is mechanically stabilized by the filler material, specifically by the solid particles, so that even under very strong forces acting on the layer from the respective section and / or over a particularly long service life of the axial flux machine, undesirable deformations and thus undesirable reductions in the layer thickness can be avoided. This ensures that the permanent magnets are and remain securely and firmly held to the substrate, thus preventing, for example, excessive relative movement between the respective permanent magnet and the substrate.

[0008] For example, the layer is formed from a first material. Preferably, the individual particle, and thus the filler, is formed from a second material that differs from the first material.

[0009] Since the layer is arranged between the sections, it acts as a spacer layer, keeping the sections at a distance from each other. Because the invention prevents undesirable deformations, particularly thickness reductions, of the layer, the sections can be advantageously held in place by the layer even under high forces and / or over a long service life of the axial flux machine, thus ensuring particularly low-loss and therefore efficient operation of the axial flux machine.

[0010] In order to achieve particularly low-loss and therefore particularly efficient and thus particularly advantageous operation of the axial flux machine and thus of the motor vehicle as a whole, one embodiment of the invention provides that the layer itself, that is, when considering the layer alone and thus when considering the layer alone without the filler, is electrically non-conductive, i.e., designed as a non-conductor. A non-conductor is a material whose electrical conductivity is less than 10 -8 S · cm -1 This allows unwanted eddy current paths and thus excessive eddy current losses to be avoided, enabling a particularly efficient and high-efficiency operation of the axial flux machine.

[0011] In order to achieve particularly efficient operation, a further embodiment of the invention provides that, when considering only the filler, i.e., the filler itself and thus when considering only the filler and without considering the layer, the filler is electrically non-conductive, i.e., designed as a non-conductor.

[0012] Since preferably the layer itself and / or the filler itself is electrically non-conductive, the layer and the filler incorporated within it form an electrical insulating layer, which prevents unwanted eddy current paths and thus undesirable eddy current losses. An electrical insulating layer is understood to be one that is electrically insulating, i.e., electrically non-conductive and therefore a non-conductor. Thus, for example, the insulating layer is used as magnetic insulation to electrically isolate the respective permanent magnet, particularly from the substrate.

[0013] Alternatively or additionally, it is conceivable that the layer itself, that is, considering the layer alone, acts as an adhesive by means of which the respective permanent magnet is bonded to the substrate and thus attached to it. Thus, alternatively or additionally, the layer is used as a magnetic adhesive to bond the respective permanent magnet to the substrate and thus attach it to the substrate. Alternatively or additionally, the layer is used, for example, as a magnet encapsulation and / or insulating layer and / or a fixing ring for the substrate. The fixing ring of the substrate is, for example, a region of the substrate that is at least substantially ring-shaped and thus designed as a ring. Alternatively or additionally, the layer is used, for example, on webs.In other words, the support, particularly the first support element, has intermediate webs, also known as ribs, which are arranged between the permanent magnets in the circumferential direction of the rotor, and thus around the machine's axis of rotation, such that the permanent magnets and the intermediate webs are arranged alternately in the circumferential direction of the rotor. It is conceivable that, for example, the respective section of the support is formed by one of the ribs, so that, for example, the respective layer is arranged at least partially between the respective permanent magnet and the respective intermediate web in the circumferential direction of the rotor.

[0014] The aforementioned magnet encapsulation involves, for example, the application of a layered material, in which the particles and thus the filler can be incorporated, in a liquid state between the respective components. This material then hardens, forming the layer. This allows for the advantageous, at least partial or even complete, encapsulation of the permanent magnet. This provides particularly effective protection against unwanted corrosion for the permanent magnet and / or its substrate.

[0015] It is also evident that the filler is a mechanically stable and, for example, electrically non-conductive additive, which stabilizes the layer and thus ensures an advantageously high mechanical stability, thereby preventing excessive deformation of the layer.

[0016] To stabilize the layer particularly advantageously and thus ensure particularly advantageous operation, a further embodiment of the invention provides that at least some of the particles, i.e., at least some of the particles, are made of glass. In other words, it is conceivable that at least some of the particles are made of glass. It is conceivable that all, and in particular all, of the particles incorporated into the layer are made of glass.

[0017] It has proven particularly advantageous if at least some of the particles, for example, a second portion of the particles, are made of ceramic. Thus, it is conceivable that a second portion of the particles are made of ceramic and are therefore ceramic particles. In particular, it is conceivable that all particles incorporated into the layer are made of ceramic and are therefore ceramic particles. This can ensure a particularly high mechanical stability of the layer.

[0018] The particles, and thus the filler, are incorporated into the layer in such a way that each particle is at least partially, in particular at least predominantly and thus at least more than half, or completely and thus fully embedded in the layer. This allows the layer to be mechanically stabilized particularly effectively.

[0019] Another embodiment is characterized in that at least some of the particles are shaped as spheres. Preferably, all, or in particular all, of the particles are shaped as spheres. This allows the layer to be mechanically stabilized particularly advantageously.

[0020] In order to be able to stabilize the layer particularly mechanically by means of the filler, it is provided in a further embodiment of the invention that the smallest outer dimension of the respective particle is at least 1 micrometer.

[0021] In order to mechanically stabilize the layer advantageously, but on the other hand not to unduly impair a function of the layer itself, it is provided in a further embodiment of the invention that the largest outer dimension of the respective particle is at most 500 micrometers.

[0022] Preferably, the diameter of each sphere is in a range of 1 micrometer or 500 micrometers or inclusive, respectively.

[0023] To achieve particularly efficient operation, a further embodiment of the invention provides that the respective permanent magnet is completely surrounded by the respective layer, at least in the respective cutting plane intersecting the respective permanent magnet and along a respective circumferential direction extending in the respective cutting plane. It is conceivable that the respective permanent magnet is completely and thus fully surrounded by the respective layer. This allows for particularly advantageous mechanical stability of the rotor overall. Especially if the layer and / or the filler is electrically non-conductive, particularly advantageous electrical insulation of the respective permanent magnet can be achieved, thus avoiding excessive eddy current losses.This ensures particularly low-loss and therefore particularly efficient operation of the axial flux machine.

[0024] A second aspect of the invention relates to an axial flux machine for a motor vehicle, also referred to simply as a vehicle, wherein the axial flux machine according to the second aspect of the invention comprises at least or exactly one rotor according to the first aspect of the invention.

[0025] Advantages and advantageous embodiments of the first aspect of the invention are to be regarded as advantages and advantageous embodiments of the second aspect of the invention and vice versa.

[0026] The invention is based in particular on the following findings and considerations: In axial flux machines, also known as axial flux motors, laminated permanent magnets are currently fixed in a magnet cassette. The magnet cassette is, for example, the aforementioned carrier or the first carrier element, wherein the carrier, in particular the first carrier element, has a support ring, in particular an inner ring, on which, for example, the permanent magnets are supported at least indirectly, in particular directly, in the radial direction of the rotor. For example, the support ring is the aforementioned fixing ring. It is conceivable that the carrier, in particular the first carrier element, has an outer ring on which the permanent magnets are supported at least indirectly, in particular directly, in the radial direction of the rotor.This prevents excessive losses, making particularly efficient operation possible.

[0027] It is conceivable that the support ring, the outer ring, and the intermediate webs are all formed as a single unit, i.e., from a single piece. Therefore, it is preferably provided that the support ring, the outer ring, and the intermediate webs are not formed and connected separately, but rather that they are formed as a single unit, thus being integrally manufactured and therefore formed as a monoblock. It is conceivable that the respective section of the support is formed by the support ring and / or the outer ring.

[0028] Advantageously, the support is at least partially made of carbon fiber reinforced plastic (CFRP), in particular such that the first support element is made of carbon fiber reinforced plastic. This allows for advantageous stability of the support while simultaneously keeping its weight particularly low. The support can, for example, absorb centrifugal forces that act on the permanent magnets (also simply called magnets) when the rotor rotates around the machine's axis of rotation relative to the stator.The carrier ensures, for example, during operation of the axial flux machine, in which the rotor rotates around the machine's axis of rotation relative to the stator during operation, as well as during standstill of the rotor, which does not rotate around the machine's axis of rotation relative to the rotor, that the permanent magnets are held on and, for example, in the carrier, in particular on and, for example, in the magnet cassette, which is also simply referred to as the cassette.

[0029] Carbon fiber reinforced plastic uses carbon fibers as reinforcing fibers. These carbon fibers are electrically conductive, which, within an axial flux machine (such as an electric traction machine used in motor vehicles for purely electric propulsion), can lead to eddy currents due to an alternating magnetic field if no countermeasures are taken. These eddy currents occur both within the carbon fiber reinforced plastic itself (also known as carbon composite) and, if no countermeasures are taken, through the electrical connection of individual magnet segments via the carbon fibers, induce eddy current paths in the magnets.If no countermeasures are taken, this can lead to a significant increase in rotor losses, which can be detrimental to efficiency and magnetic performance, particularly with regard to high magnet temperatures. These temperatures lead to early 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 reduced compared to a state where power reduction does not occur. Furthermore, if no countermeasures are taken, direct contact can occur between the substrate, usually made of carbon fiber reinforced plastic, and the permanent magnet. In this case, the substrate can act as the noble cathode, and the permanent magnet—that is, the magnetic material from which the permanent magnet is made—can act as the less noble anode.This electrical contact between the cathode and the anode can lead to contact corrosion, particularly with the aid of an electrolyte, which corrodes the less noble anode, and thus the respective permanent magnet. Corrosion can also occur on the surface of the permanent magnet due to fluctuating temperatures during operation of the axial flux machine, as well as due to environmental influences. This corrosion can eventually lead to the failure of the axial flux machine over its lifetime.

[0030] The invention now makes it possible to avoid the aforementioned problems and disadvantages, thus enabling an increase in efficiency compared to conventional solutions. If the filler and / or the layer itself is designed as a non-conductor, it exhibits electrically insulating properties, thereby enabling advantageous, low-loss operation of the axial flux machine.

[0031] 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 and thereby connected to each other, in particular by means of the respective layer.

[0032] The permanent magnets are, for example, passivated permanent magnets. For instance, the individual magnet segments of each permanent magnet are bonded together using an adhesive. Preferably, the adhesive is the aforementioned layer. To enable the carrier to absorb the high centrifugal forces of the magnets resulting from high rotor speeds, the outer ring is mounted onto the permanent magnets with an interference fit or preload. To avoid excessive eddy current paths and thus excessive eddy current losses, the layer itself and / or the filler is preferably designed as a non-conductor. This prevents unwanted electrical contact between the reinforcing fibers and the permanent magnets.

[0033] To manufacture the support structure, particularly the first support element, and especially the support ring and / or the intermediate webs and / or the outer ring, fiber rovings impregnated with the matrix material (also called matrix material) are laid down using a winding process. This winding process can be, for example, a conventional winding process, an additive translational winding technique, or a robot-guided fiber placement process. Impregnation of the fiber rovings with the matrix material occurs, for example, through a soaking process. Alternatively, pre-impregnated rovings, also known as prepregs, are used.The rovings are wound, for example, onto a tube and shaped to create or maintain the geometry of the support, particularly the first support element, which may include the support ring and / or the outer ring and / or the webs, while a curing process takes place in which the matrix material hardens. After the matrix material, and thus the fiber-reinforced plastic (also simply called fiber composite), has cured, rings of a desired thickness are cut from the tube to produce the respective rotor or support, particularly the first support element. Alternatively, the rings are wound into a mold that has a target geometry, particularly a desired thickness of the support, especially of the first support element.This has the advantage that the fibers are not separated from each other when the rings are cut from the tube, meaning they run continuously, allowing the carrier to withstand particularly high radial loads. To prevent potential damage, especially due to rotation of the carrier, particularly during the mounting of permanent magnets to the carrier and vice versa, it is possible to directly wind the permanent magnets, which, for example, form a magnet cassette. For this purpose, the reinforcing fibers are laid on the magnet cassette as prepregs or wet-impregnated rovings with pretension. The rotor is, for example, a disc rotor or a rotor disk. In other words, the rotor is, for example, disk-shaped. For instance, the axial flux machine, in its fully manufactured state, has a double-rotor arrangement or a double-stator arrangement.To achieve a particularly high torque-power density, the axial flux machine preferably has a double-rotor arrangement in its fully manufactured state, which includes rotor disks, wherein, for example, the aforementioned rotor can be a first of the rotor disks. Each rotor disk includes, for example, the carrier and the permanent magnets, which, for example, form the aforementioned magnet cassette.

[0034] Through a specific winding technique, for example, used to wind the rovings onto the aforementioned tube, different fiber orientations of the reinforcing fibers, particularly within the matrix, can be generated as needed. 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 at exactly 90 degrees cannot be achieved. The layers in the composite have an orientation of approximately 89 degrees. The surfaces of the substrate, especially the first substrate element, particularly after its separation from the tube, require post-processing. Grinding processes are used for this purpose.One advantage that can be achieved by, for example, directly winding the permanent magnets with the reinforcing fibers, especially those impregnated with resin, is that this allows for advantageous adjustment of the geometry of the support, particularly of the first support element, and the reinforcing fibers can, for example, be laid in an orientation of 90 degrees in order to advantageously absorb radial loads.

[0035] The matrix, formed from a plastic and therefore designed as a plastic matrix, can be produced, for example, using pre-impregnated base materials such as SMT, BMC, or prepregs, fiber lay-ups, or an injection molding process such as CFP. Adhesion can be achieved through a manufacturing chain, particularly by inserting permanent magnets, especially with the intermediate webs, into a cavity prior to final processing of the magnetic cassette. This ensures that the permanent magnets, or the magnetic cassette, can be reliably processed along the manufacturing chain, also referred to as the process chain. Preferably, the reinforcing fibers are designed as long fibers and / or continuous fibers.

[0036] 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. For example, the permanent magnets are hard magnets, particularly laminated hard magnets. The support, especially the first support element, is made of SMC (Sheet Molding Compound). The matrix is ​​made of a reactive resin, for example. The support, especially the first support element, is pressed, for example. Laminating the permanent magnets prevents excessive eddy current losses.

[0037] It is conceivable that the layer itself, that is, that the layer when considered in isolation, is formed as a solid and thus as a solid medium, wherein the solid medium is preferably electrically insulating, and therefore electrically non-conductive.

[0038] A further insight underlying the invention is that the layer itself can be subjected to considerable stress, particularly due to a preload force from the aforementioned outer ring and / or the support ring and / or the intermediate webs. Without countermeasures, this can lead to irreversible damage to the layer, both within the manufacturing process chain for producing the rotor and during operation of the axial flux machine. This can now be avoided because, in the invention, the layer is mechanically stabilized by means of the filler. The layer can thus advantageously transmit loads or stresses without causing excessive damage to the layer and consequently to the rotor.The layer itself, that is, the layer when considered in isolation, can, for example, be formed as a solid, particularly a continuous one, and can be formed, for example, as a film, particularly a plastic film, or as another, particularly homogeneous, sheet-like structure. In particular, it is conceivable that the layer can be formed as an adhesive film, particularly made of plastic, whereby, for example, the respective permanent magnet can be bonded to the substrate by means of the adhesive film. Thus, the respective adhesive film is or forms an adhesive layer by means of which the respective permanent magnet can be bonded to the substrate and thereby attached to the substrate.Preferably, the thickness of each particle, referred to as its outer dimension, is in a range from 1 micrometer to 500 micrometers, preferably being within a narrow tolerance window, so that the overall layer formed by the layer and the filler incorporated in the layer has an at least substantially constant thickness, thus enabling the advantageous transmission of forces and loads across the entire layer.

[0039] The filler is a medium that ensures the aforementioned distance between the sub-areas and is, for example, added to the layer in a defined volume fraction. Thus, the layer has a first volume fraction of the total layer, and the filler has a second volume fraction of the total layer. In particular, the layer is formed from a first material, while the filler, i.e., the individual particle, can be formed from a second material different from the first. This allows the layer to be mechanically stabilized particularly advantageously. The filler has the function, on the one hand, of reliably transmitting acting forces. On the other hand, the filler has the function of maintaining the aforementioned distance between the sub-areas at least substantially constant and reliably throughout the process. Preferably, the filler is electrically insulating.For example, the particles are glass spheres and / or ceramic spheres. Preferably, the layer itself is designed such that adhesion between the layer and the substrate, in particular the respective intermediate web, is not impaired or is negligibly impaired.

[0040] The invention allows at least the following advantages to be realized: - Reduction of eddy current losses in the rotor due to the alternating magnetic field during operation of the axial flux machine; - Inhomogeneous electrical conductivity is significantly reduced compared to conventional solutions, leading to reduced losses in the rotor; - consistently high mechanical strength is tolerable; - Cost reduction due to a reduced proportion of rare earth elements in the permanent magnets by reducing the coercive field strength as a result of the lower temperatures during operation of the axial flux machine; - Contact corrosion between the precious material, especially the substrate, and the permanent magnet is prevented; - direct electrical insulation of the magnetic cassette and the carrier, especially the second carrier element, can be achieved, reducing eddy current losses compared to conventional solutions; - Improved magnetic performance due to reduced heat generation resulting from decreased eddy current losses in the rotor; - Increasing the efficiency of the axial flux machine by reducing rotor losses; - reduced eddy current paths within the magnetic cassette assembly, as the eddy current paths can no longer spread between the magnet segments, the intermediate webs, and the outer ring and / or the support ring; - Inhomogeneous electrical conductivity is significantly reduced, leading to reduced losses in the rotor; - Corrosion of a magnetic surface due to environmental conditions is prevented; - The passivation process of the magnets can be omitted, resulting in a cost reduction; - The complex coating process of the magnetic cassette can be eliminated, thus enabling a cost reduction.

[0041] It is advantageous if the layer, and preferably the filler, can withstand a temperature equal to, similar to, or higher than that required in a subsequent process sequence, such as during matrix curing or operation of the axial flux machine. This allows, for example, the matrix, which is designed as a reactive resin, to cure while the layer, and consequently the electrical insulation between the respective permanent magnets and the substrate, remains unaffected. Furthermore, the curing temperature of the matrix can be used, for example, to cure the adhesive formed by the layer in the same process step and, optionally but not exclusively, to bond the two components together.

[0042] In a rotor manufacturing process, for example, the layer, and with it the particles incorporated in the layer, is applied to the respective permanent magnet, particularly in a liquid state, especially by a deposition process. This can occur, for example, directly after the production of the respective permanent magnet or before a manufacturing process for producing the magnetic cassette, especially before the permanent magnets and the substrate are processed into the magnetic cassette. For example, the substrate, especially the first substrate element, can be produced by TSIM (Thermoset Injection Molding) or other fiber fabrics. The respective permanent magnet can be coated with the layer on its entire magnetic surface or only on at least or exactly one partial area.

[0043] Further advantages, features, and details of the invention will become apparent from the following description of a preferred embodiment and from the drawing. 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.

[0044] 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. A schematic sectional view of the rotor; Fig. 4 a schematic representation of a method for manufacturing the rotor; and Fig. 5 a schematic sectional view of a magnet of the rotor.

[0045] In the figures, identical or functionally equivalent elements are provided with the same reference symbols.

[0046] 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. In its fully manufactured state, the axial flux machine 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 is disk-shaped and thus a rotor disk. It is conceivable that the axial flux machine can have a complete rotor, which can be driven by 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 motor for, in particular, purely electric propulsion of the motor vehicle. The complete motor includes, for example, the rotor 10, especially as the first rotor disk.Furthermore, it is conceivable that the complete motor 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 their respective rotor disks. It is also conceivable that at least a part of the stator is arranged between the rotor disks in the axial direction of the axial flux machine, 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 part 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.

[0047] The rotor 10 has permanent magnets, which, for example, form a magnet cassette 14 of the rotor 10. The respective permanent magnet 12 is also simply referred to as a magnet.

[0048] 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, for example, in the radial direction of the rotor 10, whose axial direction coincides with the machine's axis of rotation. It is conceivable that the magnet segments 16 are formed separately from one another and connected to each other, in particular by means of an adhesive.

[0049] The rotor 10, whose radial direction is perpendicular to the axial direction of the rotor 10 and thus perpendicular to the machine's axis of rotation, also has a carrier 18 formed separately 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 metallic material.

[0050] Especially good from a combination of Fig. Figures 1 to 3 show that the support 18 comprises, for example, a first support element 19, a second support element 21, and, for example, a third support element 23. The support element 19 is made of a fiber-reinforced plastic, which is also simply referred to as a fiber composite. In the embodiment shown in the figures, the fiber-reinforced plastic is a carbon fiber reinforced plastic (CFRP), which is formed, in particular entirely, from a matrix, also referred to as a matrix material, and reinforcing fibers embedded in the matrix, which are also simply referred to as fibers. The matrix, in particular entirely, is formed from a plastic, so that the matrix is ​​also referred to as a plastic matrix. For example, the reinforcing fibers are carbon fibers.

[0051] The support element 21 is, in this case, a laminated core also referred to as an electrical steel core, which is formed from electrical steel, also simply referred to as sheet metal. In particular, the support elements 19, 21 and 23 are connected to one another, specifically in such a way that the relative movements between the support elements 19, 21 and 23, considered in pairs, are prevented.

[0052] Looks especially good Fig. As can be seen from Figure 1, 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 inwards 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 inwards in the radial direction of the rotor 10. In particular, the rings are arranged coaxially to 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 one section of the rotor shaft of the complete 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 aforementioned section of length. In particular, the complete rotor can provide the drive torques via the rotor shaft.

[0053] The separating 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, which extends around the axial 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. It is also apparent that the intermediate webs 26, which are also simply referred to as webs, are arranged between the rings, particularly in the radial direction of the rotor 10, with the rings, for example, being connected to one another via the webs. In the embodiment shown in the figures, the support element 19 is formed in one piece, so that the intermediate webs 26, the support ring 20, and the outer ring 22 are all formed in one piece, i.e., from a single component.

[0054] In order to achieve a particularly advantageous operation of the axial flux machine, at least one layer S formed from a first material is arranged between a respective sub-area TB1 of the respective permanent magnet 12 and a respective sub-area TB2 of the support element 19 and thus of the support 18, in particular opposite the respective sub-area TB1 in the circumferential direction of the rotor 10, in which a filler F mechanically stabilizing the respective layer S is contained, consisting of particles P formed as solids, wherein preferably the respective particle P is formed from a second material different from the first material.

[0055] Out of Fig. Figures 1 to 3 show that, for example, the first of the sub-areas TB2 of the carrier 18 are formed by the carrier element 19, in particular by the intermediate webs 26, such that, for example, the layer S with the filler F incorporated therein is arranged circumferentially between the respective permanent magnet 12 and the respective webs. Second of the sub-areas TB2 are formed, for example, by the carrier element 21, that is, in particular by the laminated core, such that, for example, the respective layer S is arranged radially along the rotor 10 between the respective permanent magnet 12 and the carrier element 21. Thus, for example, the respective first sub-area TB1 lies opposite the respective corresponding sub-area TB1 in the circumferential direction of the rotor 10, and, for example, the respective second sub-area TB2 lies opposite the respective corresponding sub-area TB1 in the radial direction of the rotor 10.

[0056] It is evident that layer S, together with the filler F incorporated into layer S, forms a single layer which, due to the mechanical stabilization provided by the filler F, functions particularly advantageously as a spacer layer. This spacer ensures that the respective permanent magnet 12 is maintained at an advantageous distance from the support 18, even over a long service life of the axial flux machine. This, in turn, guarantees efficient operation of the axial flux machine over a long service life.

[0057] To achieve particularly low-loss and therefore highly efficient operation of the axial flux machine, it is provided, for example, that layer S, when considering only the layer itself, is designed as a non-conductor and thus electrically non-conductive. Alternatively or additionally, it is provided that, when considering only the filler F, the filler F is also electrically non-conductive and thus designed as a non-conductor. In other words, the entire layer thus acts as a spacer medium, by means of which the respective permanent magnet 12 is advantageously held at the respective distance from the support 18.

[0058] Out of Fig. Figure 4 describes an advantageous method for manufacturing the rotor 10. In this method, a layer material, from which the layer S is produced, is supplied to a mixing unit 27, particularly in a liquid state. The layer material is supplied with the filler F, and thus with the particles P. The supply of the layer material to the mixing unit 27 is illustrated by arrow 28, and the supply of the filler F to the mixing unit 27 by arrow 30. By means of the mixing unit 27, and particularly within the mixing unit 27, the layer material, which is, for example, the aforementioned first material, is mixed with the particles P, and thus with the filler F, as illustrated by arrow 32. This mixture distributes the particles P throughout the layer material. A mixture is thereby produced that comprises the layer material, particularly in a liquid state, and the particles P contained within the layer material, particularly in a liquid state.The mixture from the mixing unit 27 is fed to coating units 34, by means of which the mixture, particularly in a liquid state, is applied to the respective permanent magnets 12, specifically such that a first coating unit 34 applies the mixture to a first side S1 of the respective permanent magnet 12 and a second coating unit 34 applies the mixture to a respective second side S2 of the respective permanent magnet 12, the mixture being applied, for example, simultaneously to sides S1 and S2. It can be seen that sides S1 and S2 point away from each other. For example, a first side S1 and S2 forms a respective first sub-area TB1, and the other side S2, S1 forms a respective second sub-area TB1 of the respective permanent magnet 12.After the mixture is applied to sides S1 and S2, the layer material can harden, whereby the layer S is produced from the layer material, in which the filler F and thus the particles P are included, in particular embedded.

[0059] Fig. 5 shows the permanent magnet 12 from Fig. 4 after the permanent magnet 12 has been coated with the mixture and thus with the entire layer. This is evident from Fig.As described in sections 3 to 5, preferably the respective permanent magnet 12 is surrounded by the respective layer S and thus by the respective overall layer, at least in a respective cutting plane intersecting the respective permanent magnet 12 and extending perpendicular to the axial direction of the rotor 10, and along a respective circumferential direction of the respective permanent magnet 12 extending in the respective cutting plane and defined by an arrow 38. This allows, for example, the respective permanent magnet 12 to be particularly advantageously electrically insulated from the support 18, especially if the overall layer has electrically insulating properties. This can be achieved, in particular, by designing the layer S and / or the filler F as a non-conductor. Reference symbol list 10 Rotor 12 permanent magnets 14 magnetic cassettes 16 magnetic segments 18 carriers 19 first support element 20 support ring 21 second support element 22 Outer ring 23 third support element 24-hour opening 26 Intermediate walkway 27 Mixing unit 28 Arrow 30 Arrow 32 Arrow 34 coating units 38 Arrow Area B F Filler P particles S layer S1 page S2 page TB1 Sub-area TB2 Sub-area 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]

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