Rotor and method for producing rotor

Abstract

The invention relates to a rotor (1) for an axial flux machine (2), in particular for an axial flux machine (2) in a drive train (3) of a motor vehicle (4), comprising an inner ring (5) and an outer ring (6) arranged coaxially with respect to the inner ring, reinforcing struts (7) extending in the radial direction being arranged in the form of spokes between the inner ring (5) and the outer ring (6), a respective magnetic element (8) is arranged between two reinforcing struts (7) adjacent in the circumferential direction, a respective coupling element (9) is arranged on both sides of one of the reinforcing struts between one of the magnetic elements (8) and the corresponding reinforcing strut (7) in the circumferential direction, and wherein the coupling element (9) is arranged between one of the magnetic elements (8) and the corresponding reinforcing strut (7), and wherein the coupling element (9) is arranged in the circumferential direction between one of the magnetic elements (8) and the corresponding reinforcing strut (7). The coupling elements (9) are formed from a material different from the material of the inner ring (6) and / or the outer ring (6) and / or the magnetic elements (8) and / or the reinforcing struts (7).

Description

Technical Field

[0001] This invention relates to rotors for axial flux machines, particularly rotors for axial flux machines in the transmission systems of motor vehicles. The rotor includes an inner ring and an outer ring arranged coaxially with the inner ring. Reinforcing struts extending radially between the inner and outer rings are arranged in a spoke-like manner, and magnetic elements are arranged between each pair of circumferentially adjacent reinforcing struts. The invention also relates to a method for manufacturing the rotor. Background Technology

[0002] Electric motors are increasingly being used to power motor vehicles as an alternative and addition to internal combustion engines that require fossil fuels. Significant efforts have been made to improve the suitability of electric drives for everyday use and to provide users with the driving comfort they are accustomed to.

[0003] A detailed description of the electric drive, possibly the closest existing technology, can be found in the article entitled "Hochintegrativ undflexibel – Elektrische Antriebseinheit für E-Fahrzeuge [Highly Integrated and Flexible Electric Drive Unit for Electric Vehicles]" published by Erik Schneider, Frank Fickl, Bernd Cebulski, and Jens Liebold in the German automotive magazine ATZ, May 2011, Vol. 113, pp. 360-365. This article describes a drive unit for a vehicle axle comprising an electric motor arranged coaxially with a bevel gear differential. Such a drive unit is also referred to as an electric axle or an electrically driven transmission.

[0004] Axial flux motors are increasingly used in the axles of such electric vehicles. An axial flux motor is an electric generator in which the magnetic flux between the rotor and stator extends parallel to the rotor's axis of rotation. Typically, both the stator and rotor are primarily disc-shaped. Axial flux motors are particularly advantageous when axial mounting space is limited in a given application. This is often the case, for example, with the electric drive systems of the electric vehicles described at the beginning. Besides the reduced axial mounting length, another advantage of axial flux motors is their relatively high torque density. This is due to the larger available air gap surface area and lever arm for a given mounting space compared to radial flux motors. Furthermore, less iron volume is required compared to conventional machines, which positively impacts the machine's efficiency.

[0005] Due to the disc-shaped main component of the axial flux motor, it is particularly suitable for applications where a very short overall length of the motor is important and a relatively large motor diameter is still acceptable. Therefore, when developing a corresponding axial flux motor, it is generally recommended to aim for the most compact design possible, while ensuring that the outer diameter of the axial flux motor does not exceed the necessary size. In the case of axial flux motors used in motor vehicles, there is always a requirement for low weight, high power density, and low cost.

[0006] The purpose of a disc-shaped rotor is primarily to transmit the forces acting on the rotor magnets to the rotor shaft. In addition to the circumferential direction, the magnets must be positioned radially and axially, or between the stators.

[0007] Due to centrifugal force and outwardly extending components, unfavorable circumferential tensile stresses are generated between and within the rotor components. Summary of the Invention

[0008] Therefore, an object of the present invention is to provide a rotor for an electric axial flux machine that is inexpensive to manufacture and easy to assemble, and allows for good adjustability of the rotor's circumferential stiffness. Another object of the present invention is to provide an improved method for manufacturing the rotor.

[0009] This objective is achieved by a rotor for an axial flux machine, particularly a rotor for an axial flux machine in the transmission system of a motor vehicle, the rotor comprising an inner ring and an outer ring arranged coaxially relative to the inner ring, wherein reinforcing struts are arranged in a spoke-like manner extending radially between the inner and outer rings, and corresponding magnetic elements are arranged between two circumferentially adjacent reinforcing struts, wherein corresponding connecting elements are arranged circumferentially on both sides of one of the reinforcing struts and between one of the magnetic elements and the corresponding reinforcing strut, and wherein the connecting elements are formed of a material different from that of the inner ring and / or the outer ring and / or the magnetic elements and / or the reinforcing struts.

[0010] This has the following advantages: the connecting elements can be used to connect rotor components (reinforcing struts, magnetic elements, inner ring, outer ring) to each other in the circumferential direction. Therefore, the material and geometry of the connecting elements can be adjusted so that they can withstand relative displacement and perform load transfer. In particular, the connecting elements, due to their preferably given elasticity, can simultaneously reduce pressure on their contact surfaces. Furthermore, the circumferential stiffness of the rotor (especially in the region within the band) can be adjusted in a targeted manner, for example, via the elastic modulus of the connecting elements in the plane of the disc and the geometry of the connecting elements.

[0011] Therefore, the connecting element allows for relative displacement between the components, and despite the circumferential connection, the contact stress between the components can remain low. Furthermore, the connecting element supports the transfer of magnetic loads (due to centrifugal force) generated during rotor operation to the reinforcing element.

[0012] Connecting elements can be produced, for example, by injection molding or by potting with filled, reinforced, or unreinforced polymers. Connecting elements can also be produced using adhesive compounds. Connecting elements can also be produced directly during the molding process and subsequently joined, for example, via adhesive bonding.

[0013] First, the various elements of the claimed subject matter of the present invention are interpreted in the order in which they are mentioned in the claims, and then particularly preferred embodiments of the subject matter of the present invention are described.

[0014] In an electric axial flux motor (AFM), such as in a motor vehicle, the magnetic flux in the electrically driven machine is axially directed in the direction of rotation of the rotor of the axial flux motor within the air gap between the stator and rotor.

[0015] Depending on the application, it may be advantageous to design the axial flux motor in an I-type or H-type arrangement. In an I-type arrangement, the rotor is arranged axially adjacent to the stator or between the two stators. In an H-type arrangement, the two rotors are arranged on opposite axial sides of the stator. The axial flux motor according to the invention is preferably constructed in an I-type arrangement.

[0016] In principle, multiple rotor-stator configurations can also be arranged axially adjacently as type I and / or type H. In this context, multiple type I rotor-stator configurations can also be arranged adjacent to each other along the axial direction. In particular, it is preferred that the type H and / or type I rotor-stator configurations are each formed substantially identically, so that these rotor-stator configurations can be assembled in a modular manner to form an integral configuration. Specifically, such rotor-stator configurations can be arranged coaxially with each other and can be connected to a common rotor shaft or multiple rotor shafts.

[0017] The stator of an electric axial flux motor preferably has a stator body having multiple stator windings arranged circumferentially. When viewed circumferentially, the stator body can be formed as a single section or segmented sections. The stator body can be formed from a stack of stator sheets having multiple laminated electrical steel sheets. Alternatively, the stator body can also be formed from compressed soft magnetic material, such as so-called SMC (soft magnetic composite) material.

[0018] The stator is housed within a housing. The housing may be formed as one part or multiple parts. The housing is particularly preferably made of plastic. The housing may be designed to be closed on all sides. Openings may also be provided in the housing, for example, to reduce weight or to provide access to components.

[0019] Magnetic elements can be designed as permanent magnets, for example. Preferably, the magnetic elements are designed to be substantially identical.

[0020] The rotor shaft is the shaft of the motor that is rotatably mounted, and the rotor or rotor body is non-rotatably connected to the rotor shaft.

[0021] Furthermore, the electric axial flux machine may have a control unit. The control device used in this invention is specifically for the electronic control and / or regulation of one or more technical systems of the electric axial flux machine.

[0022] The electric axial flux motor is particularly intended for use in the drivetrains of hybrid or all-electric motor vehicles. Specifically, the motor is sized to achieve vehicle speeds of more than 50 km / h, preferably more than 80 km / h, and particularly more than 100 km / h. The electric motor particularly preferably has an output of more than 30 kW, preferably more than 50 kW, and particularly more than 70 kW. Furthermore, it is preferred that the motor provides a rotational speed greater than 5000 rpm, particularly preferably greater than 10000 rpm, and very particularly preferably greater than 12500 rpm.

[0023] The electric axial flux motor can preferably also be installed in an electrically operated axle drivetrain. The electric axle drivetrain of a motor vehicle includes an electric axial flux motor and a transmission device, wherein the electric axial flux motor and the transmission device form a structural unit. In particular, it can be specified that the electric axial flux motor and the transmission device are arranged in a common drivetrain housing. Particularly preferably, this drivetrain housing can also form a connection structure for the axial flux motor. Alternatively, the electric axial flux motor can of course also have a motor housing, and the transmission device can of course also have a transmission device housing; in this case, the structural unit can then be implemented by fixing the transmission device relative to the electric axial flux motor. This structural unit is sometimes also referred to as an electric axle.

[0024] Magnetic components The magnetic element preferably has a longitudinal extension and is characterized by a circumferential profile. When the magnetic element is installed in the rotor, a longitudinally extending flat first surface portion and a longitudinally extending flat or freely formed second surface portion are formed on a first side facing a first rotation direction of the rotor. When the magnetic element is installed in the rotor, the first surface portion is radially positioned above the second surface portion. When the magnetic element is installed in the rotor, a longitudinally extending flat third surface portion and a longitudinally extending flat or freely formed fourth surface portion are formed on a second side facing a second rotation direction of the rotor.

[0025] Preferably, when the magnetic element is installed in the rotor, the third surface portion is radially positioned above the fourth surface portion, wherein when the magnetic element is installed in the rotor, a first plane extending through the first surface portion and a third plane extending through the third surface portion intersect radially above the magnetic element in a longitudinally extending direction, and when the magnetic element is installed in the rotor, a second plane extending through the second surface portion and a fourth plane extending through the fourth surface portion intersect radially below the magnetic element in a longitudinally extending direction.

[0026] This offers the following advantages: particularly on the flat first and flat third surface portions, straight and flat surfaces that can be precisely and economically produced can be provided in sub-regions of the circumferential profile of the magnetic element, which can be effectively sealed during injection molding or adhesive bonding to form the rotor. Furthermore, the flat first and flat third surface portions allow for particularly precise radial positioning of the magnetic element.

[0027] Furthermore, the flat first and third surface portions can establish a "center-of-mass to contact surface" relationship for the magnetic element. Therefore, the flat first and third surface portions can be used as a reference when sorting or distributing the magnetic element relative to its center of mass. This enables geometric balance, or minimizes rotor imbalance through geometric sorting.

[0028] Then, by taking into account the weight of the magnetic elements, sorting and / or arranging of the magnetic elements can be performed additionally or in combination to reduce imbalance. This optimizes the positioning accuracy of the magnetic elements so as to minimize the imbalance caused by the uneven positioning of the sorted magnetic elements in the rotor. Therefore, by sorting the magnets, taking into account geometric and mass deviations, and distributing the magnets to specific positions in the rotor, the accuracy of rotor balance affected by the magnetic elements can be optimized.

[0029] Therefore, the flat first surface portion and the flat third surface portion provide areas along the circumferential magnet profile, which are geometrically simplified (flat, straight surface portions) and can therefore be manufactured inexpensively and precisely. As mentioned above, the flat first surface portion and the flat third surface portion can also be used as sealing surfaces during production.

[0030] When the magnetic element is installed in the rotor, a first plane extending through the first surface portion and a third plane extending through the third surface portion intersect radially above the magnetic element in a longitudinally extending direction. The flat first surface portion and the flat third surface portion have contact lines with an outwardly closing direction, and thus can be used as a positioning option for the magnetic element in rotor production.

[0031] The circumferential profile of a magnetic element can be realized, for example, in a sintering tool, on individual disks of a laminated magnetic element, or directly on the entire magnet. The geometric features of the circumferential profile can be formed before passivation or after passivation through additional passivation or subsequent processes with passivation effects. The geometric features of the circumferential profile can be used on segmented magnets and monolithic magnets. The geometric details of the circumferential profile can be realized symmetrically or asymmetrically, and / or partially on or within the circumferential profile.

[0032] For the purposes of this invention, the flat surface portion is a flat two-dimensional surface. This means that for any two points in the surface portion, a straight line will lie entirely within the surface portion. The surface portion itself may also have local non-uniformity, in which case an average plane is placed through the corresponding surface portion.

[0033] Magnetic elements can be designed as permanent magnets, for example. Preferably, the magnetic elements are designed to be substantially identical.

[0034] According to an advantageous embodiment of the invention, the magnetic element is formed in a mirror-symmetrical manner with respect to its longitudinal extension. This embodiment has the advantage of improving the ease of rotor assembly and balance.

[0035] According to another preferred embodiment of the invention, the circumferential profile may at least partially have a chamfer formed at the transition between the circumferential profile and the axial surface. By providing a profile in the transition from the axial magnet region to the circumferential magnet region, the adhesive joints in these regions can be depressurized or their load-bearing capacity can be increased.

[0036] The chamfered portion also allows for a more flexible connection with the injection-molded surface or adhesive surface.

[0037] Furthermore, according to equally advantageous embodiments of the invention, it can be specified that the flat first surface portion and / or the flat or freely formed second surface portion and / or the flat third surface portion and / or the flat or freely formed fourth surface portion each have at least partially a structure protruding from or recessed into the respective flat surface. This allows for the provision of macroscopic shape details, particularly on one or more surface portions of the magnetic element, that improve the transfer of (centrifugal) force to the corresponding adhesive surface and / or directly overmolded area in the mounted state of the magnetic element.

[0038] According to another particularly preferred embodiment of the invention, the circumferential profile may be specified to have a fifth surface portion that, when mounted in the rotor, is radially outwardly oriented and connects the first surface portion to the third surface portion, wherein the fifth surface portion has an arcuate profile, and wherein the axis of rotation extends coaxially with the axis of rotation of the rotor. By specifying the arcuate radial outer profile, uniform (centrifugal) load transfer to the rotor's support components, such as auxiliary bandages or load bandages, can be achieved for both non-laminated and laminated magnetic elements.

[0039] Furthermore, the invention can be further improved such that the circumferential profile has a sixth surface portion that, when mounted in the rotor, is radially inwardly oriented and connects the second surface portion to the fourth surface portion, wherein the sixth surface portion has a chamfered portion formed at the transition between the sixth surface portion and the axial surface. This achieves a wedge shape for the sixth surface portion, which, for example, can improve the connection with the inner ring of the rotor.

[0040] In principle, magnetic components can be positioned via contact surfaces, but they can also be positioned via contact points.

[0041] In another preferred embodiment of the invention, the magnetic element may be further specified to have an upper region and a lower region, wherein the upper region extends upward by half of the longitudinal extension of the magnetic element, and the lower region extends downward by half of the longitudinal extension of the magnetic element, and the first surface portion and the third surface portion extend only within the upper region of the magnetic element. This allows the magnetic element to be balanced or positioned within the rotor via the upper region of the magnetic element.

[0042] Furthermore, it is conceivable that rotor balance can be achieved through the lower region.

[0043] It is also advantageous to further improve the invention so that the magnetic element is laminated or integrally formed.

[0044] Connecting elements Preferably, in each of the reinforcing struts, a connecting element is arranged circumferentially on both sides of the reinforcing strut between one of the magnetic elements and the corresponding reinforcing bracket, wherein the connecting element is formed of a material different from the material of the inner ring and / or outer ring and / or magnetic element and / or reinforcing strut.

[0045] In principle, it is also envisioned that at least one connecting element is arranged between each pair of circumferentially adjacent magnetic elements, the connecting element being connected radially to at least one of the magnetic elements in a force-transmitting manner.

[0046] According to an advantageous embodiment of the invention, the connecting element can be specified to be formed of a material with an elastic modulus between 400 MPa and 46000 MPa. The advantage of this embodiment is that it can provide sufficient stiffness difference for the rotor's magnets to achieve particularly good connection characteristics.

[0047] According to another preferred embodiment of the invention, the connecting element may be formed of a material that has elastic properties during rotor operation. This ensures that the contact surfaces of the connecting element and adjacent components can reduce load.

[0048] Furthermore, another advantageous embodiment of the invention may specify that the connecting element is rod-shaped and has an average thickness of at least 0.4 mm, preferably 0.4 mm to 2 mm, and particularly preferably 0.5 mm to 1.5 mm in the circumferential direction. The advantage of this embodiment is that it allows for a minimum level of flexibility for disconnecting the connection.

[0049] According to another particularly preferred embodiment of the invention, the connecting element may have at least one connecting portion that deviates from the shape of the rod and at least partially rests against one of the magnetic elements. This particularly makes it possible to achieve, for example, better transmission of the radial force component between the connecting element and the magnetic element by the corresponding connecting portion of the connecting element surrounding the magnetic element in a form-fitting manner.

[0050] Furthermore, the present invention can be further improved to make the connecting elements substantially identical, which can also have a positive impact on manufacturing costs due to the higher degree of uniformity.

[0051] In another preferred embodiment of the invention, it may also be specified that the reinforcing struts are cubic, wherein each connecting element rests at least partially on the longitudinal surface of one of the reinforcing struts. This ensures that the load is uniformly transferred from one reinforcing element to the connecting element without local peaks.

[0052] The rotor can be manufactured by the following method: This method is used to manufacture rotors for axial flux motors, particularly rotors for axial flux motors in the transmission systems of motor vehicles, and includes the following steps: - Provides molding tools, - Provides multiple reinforcing pillars, - Offers multiple magnetic components, - Reinforcing struts and magnetic elements are arranged in a molding tool such that the reinforcing struts are positioned in a spoke-like manner, and the magnetic elements are arranged between each pair of circumferentially adjacent reinforcing struts. Furthermore, an air gap is provided on both sides of each reinforcing strut in the molding tool, between one of the magnetic elements and the corresponding reinforcing support. - Use a molding tool to injection mold the inner and outer rings, thus fixing the positions of the reinforcing struts, magnetic components, inner and outer rings relative to each other. - The air gaps on both sides of one of the reinforcing pillars are filled with a material different from that of the inner ring and / or outer ring and / or magnetic elements and / or reinforcing pillars, so that a connecting element is formed between one of the magnetic elements and the corresponding reinforcing support.

[0053] Alternatively, the rotor can also be manufactured by the following method: This method, used for producing rotors for axial flux machines, particularly rotors for axial flux machines in the drivetrain of motor vehicles, includes the following steps: - Provides molding tools, - Provides multiple reinforcing pillars, - Offers multiple magnetic components, - Provide multiple connecting elements made of materials different from those of the inner ring and / or outer ring and / or magnetic elements and / or reinforcing supports. - Reinforcing struts and magnetic elements are arranged in a molding tool such that the reinforcing struts are positioned in a spoke-like manner, and the magnetic elements are arranged between each pair of circumferentially adjacent reinforcing struts. Furthermore, an air gap is provided on both sides of each reinforcing strut in the molding tool, between one of the magnetic elements and the corresponding reinforcing support. - Use a molding tool to injection mold the inner and outer rings, thus fixing the positions of the reinforcing struts, magnetic components, inner and outer rings relative to each other. - Insert the connecting element into the air gap on both sides of one of the reinforcing struts.

[0054] The connecting element can also optionally be connected to an adjacent component structure.

[0055] bandage components According to another preferred embodiment of the invention, the rotor may have an inner ring and an outer ring arranged coaxially with the inner ring, wherein reinforcing struts extending radially between the inner and outer rings are arranged in a spoke manner, and magnetic elements are arranged between each pair of circumferentially adjacent reinforcing struts, wherein annular bandage elements are rested on the outer ring by press fitting, such that prestress is introduced into the rotor via the bandage elements.

[0056] Bandage elements can be manufactured, for example, using machining methods. It is also conceivable that bandage elements are pressed, wound, or laid out, wholly or partially. Bandage elements can also be formed, wholly or partially, by injection molding or casting. Furthermore, bandage elements can be formed through a wet winding process or by pre-impregnation.

[0057] Preferably, the bandage element has a circumferentially closed profile. Particularly preferably, the bandage element has a polygonal cross-sectional profile that deviates from a circular path on its inner surface facing the outer ring.

[0058] Most preferably, the auxiliary bandage of the bandage element has a polygonal cross-sectional profile that deviates from a circular path on its inner surface facing the outer ring. It is also preferred that the auxiliary bandage of the bandage element has a polygonal cross-sectional profile that deviates from a circular path on its outer surface facing away from the outer ring. Preferably, the polygonal cross-sectional profile on the outer surface of the auxiliary bandage substantially corresponds to the polygonal cross-sectional profile on the inner surface. Similarly, the load-bearing bandage of the bandage element preferably also has a polygonal cross-sectional profile that deviates from a circular path on its inner surface facing the auxiliary bandage.

[0059] The bandage element can be at least partially formed of plastic. Particularly preferred is that the plastic is arranged in a circumferentially closed manner on the bandage element. Reinforced plastic, particularly fiber-reinforced plastic, is particularly preferred. The fiber-reinforced plastic material can comprise short fibers, long fibers, or continuous fibers, or a mixture of short fibers, long fibers, and continuous fibers. It is also conceivable that the bandage element is made of a metallic material, particularly steel, and / or ceramic, at least partially and preferably continuously surrounding the bandage.

[0060] The bandage element may be made of multiple parts, which may be made of the same material or partially different materials, wherein preferably at least one material of the bandage in the circumferential direction must have an elastic modulus greater than 48,000 MPa.

[0061] The bandage element can be formed directly onto the outer ring of the rotor in the initial forming process, or it can be attached to the outer ring after it has been formed.

[0062] It is also conceivable that the bandage element is machined in at least some areas before and after attachment to the outer ring.

[0063] The bandage element can completely or partially cover the outer ring of the rotor in the axial direction. In this case, as complete axial overlap as possible is preferred because it enables particularly high and uniform application of pressure.

[0064] In particular, it is advantageous that multiple bandage elements are arranged axially on the rotor in series, which has the following advantages: the bandage elements can be modularly constructed and flexibly adapted to the length of the rotor.

[0065] It is also advantageous to further modify the invention so that the annular auxiliary bandage rests on the outer ring. The connecting element, together with the prestressed auxiliary bandage, allows the rotor disk to withstand circumferential pressure over its entire extension. This ensures that the average stress of the stress amplitude shifts towards the compression direction during operation, which in turn has a positive impact on durability.

[0066] According to an advantageous embodiment of the invention, the bandage element can be designed as several parts, wherein at least one annular auxiliary bandage rests on the outer ring and at least one annular load-bearing bandage rests on the auxiliary bandage. This embodiment has the advantage of allowing for better and more precise control over the prestress introduced into the rotor and the operating loads in the rotor and bandage.

[0067] According to another preferred improvement of the invention, the auxiliary bandage is made of a different material than the load bandage, thereby further optimizing the adjustability of prestress and operating load in the rotor and bandage. This means, for example, that the magnet and radial support at least partially determine the deflection point of the polygonal profile, and thus increase the initial stiffness of the installed bandage.

[0068] Furthermore, according to an equally advantageous embodiment of the invention, it can be specified that at least one material of the multi-part bandage element, particularly the load-bearing bandage, has an elastic modulus greater than 48,000 MPa in the circumferential direction of the bandage element. The advantageous effect of this embodiment is based on the fact that the bandage, due to its increased circumferential stiffness, can absorb the associated operating loads and thus reduce stress on the rotor disc.

[0069] According to another particularly preferred embodiment of the invention, the prestress introduced into the rotor by the auxiliary bandage can be specified to be greater than the prestress introduced by the load bandage. This allows for specific control of the ratio of average stress to stress amplitude in the bandage, particularly when using different materials. It also allows for optimization of the press fit force according to tolerance requirements.

[0070] Furthermore, the invention can be further improved such that the load-bearing bandage rests on the auxiliary bandage, so that the auxiliary bandage does not introduce any prestress into the rotor. The advantage of this embodiment is that the average stress in the bandage element is minimized.

[0071] In another preferred embodiment of the invention, it may also be specified that the outer ring has a polygonal circumferential outer contour with multiple support points.

[0072] In this context, it is particularly preferred that the support points of the polygonal profile are determined by load-introducing elements. For example, this allows the magnet and radial support to at least partially determine the deflection points of the polygonal profile, thereby increasing the initial stiffness of the installed bandage.

[0073] If the centrifugal load of the magnet is introduced relatively discretely into a cylindrical or near-cylindrical bandage element, such a bandage element may only provide low stiffness in a first load region. The first load region is, for example, the load region generated by centrifugal force or thermal expansion during rotor operation.

[0074] This results in a large range of motion between components and a corresponding load range. If the bandage element is polygonal along its load introduction and support points, the bandage element can have advantageous stiffness and absorb the corresponding load particularly well.

[0075] It is also advantageous to further improve the invention so that the bandage element and the outer ring are formed as a single piece, particularly integrally. This has the following advantages: the load-bearing bandage can even be moved closer to the load-generating component (magnet), and thus can absorb the load more effectively. Similarly, the load transmission path with less stiffness is reduced, resulting in a rigid connection with less relative motion.

[0076] The rotor can be manufactured by, for example, a method including the following steps: • A rotor with an inner ring is provided, wherein reinforcing struts extending radially outward from the inner ring are arranged in the rotor in a spoke-like manner, and magnetic elements are arranged between each pair of circumferentially adjacent reinforcing struts. • The annular bandage element is arranged on the outer contour of the rotor by press fitting, so that the prestress is introduced into the rotor through the bandage element. Connect the rotor to the rotor shaft.

[0077] The method can also be adapted to provide a rotor having an inner ring and an outer ring arranged coaxially with the inner ring, wherein reinforcing struts extending radially between the inner and outer rings are arranged in a spoke-like manner, and magnetic elements are arranged between each pair of circumferentially adjacent reinforcing struts.

[0078] In another method step, the inner ring can be partially or completely removed from the rotor, for example, by milling.

[0079] Cover disk According to an advantageous embodiment of the invention, at least one reinforcing strut and / or at least one magnetic element is connected to at least one cover plate, which at least partially covers the rotor on a second end face of the rotor, such that during rotor operation, force can be transmitted from one of the reinforcing struts and / or at least one magnetic element to the at least one cover plate, and / or force can be transmitted from the at least one cover plate to one of the reinforcing struts and / or at least one magnetic element. Further improvements in axial stiffness, distribution of stress peaks, acoustic properties, and wear resistance can be achieved by at least partially covering the rotor on two end faces of the rotor using cover plates.

[0080] According to another preferred improvement of the invention, the cover disk located on the first end face of the rotor and / or the cover disk located on the second end face of the rotor are formed in the shape of annular disks, which has proven to be particularly advantageous in terms of manufacturing cost and for operational reliability.

[0081] According to an advantageous embodiment of the invention, the cover disk located on the first end face of the rotor and / or the cover disk located on the second end face of the rotor can be defined as being formed of multiple parts. In particular, it is conceivable that the cover disk located on the first end face of the rotor and / or the cover disk located on the second end face of the rotor can be formed of disk elements stacked in layers. The stacked disk elements can be made of the same material or different materials. Besides the laminated, axially multi-part structure, the cover disk located on the first end face of the rotor and / or the cover disk located on the second end face of the rotor can also be formed of multiple parts in the circumferential direction, for example, formed as annular segments. In principle, it is also advantageous to design the cover disk located on the first end face of the rotor and / or the cover disk located on the second end face of the rotor as multiple parts in the radial direction, for example, as annular disks arranged coaxially with each other.

[0082] Preferably, the cover disks located on the first end face of the rotor and the cover disks located on the second end face of the rotor each include ferromagnetic material in the overlapping and / or contact areas with the magnetic elements.

[0083] The cover plate located on the first end face of the rotor and the cover plate located on the second end face of the rotor can also partially cover, completely cover, or even protrude from the corresponding end face.

[0084] In principle, the cover plate located on the first end face of the rotor and / or the cover plate located on the second end face of the rotor can be designed to be flat or contoured.

[0085] It is also advantageous that the cover discs located on the first end face of the rotor and / or on the second end face of the rotor have been at least partially, preferably completely, surface-treated on their surfaces facing away from and / or towards the rotor, thereby allowing for further modification and adjustment of the cover discs relative to the specific operating conditions of the rotor. In this context, the cover discs located on the first end face of the rotor and on the second end face of the rotor may also be at least partially, preferably completely, coated on their surfaces facing away from and / or towards the rotor, for example, using paint.

[0086] In particular, it is conceivable that the cover plate located on the first end face of the rotor and / or the cover plate located on the second end face of the rotor are designed as a single piece with one or more other components of the rotor, such as the outer ring and / or bandage elements. The cover plate located on the first end face of the rotor and the cover plate located on the second end face of the rotor can be directly attached to these components in the primary forming method or can be subsequently attached to these components.

[0087] In particular, the cover plate located on the first end face of the rotor and / or the cover plate located on the second end face of the rotor may be at least partially post-processed after being assembled onto the rotor, particularly by at least partially post-processing methods.

[0088] Furthermore, according to an equally advantageous embodiment of the invention, it may be specified that the cover disc located on the first end face of the rotor and / or the cover disc located on the second end face of the rotor are formed of plastic, particularly fiber-reinforced plastic and / or spherical-reinforced plastic, non-magnetic steel, aluminum or ceramic.

[0089] According to another particularly preferred embodiment of the invention, it can be specified that the cover discs located on the first end face of the rotor and the cover discs located on the second end face of the rotor radially protrude beyond the edge of the outer ring, and the bandage element rests axially on the outer ring between the cover discs. This particularly makes it possible for the cover discs to function as receiving and guiding elements for the bandage element during the assembly of the bandage element onto the rotor and during the operation of the rotor.

[0090] Furthermore, the invention can be further modified such that the cover plate on the first end face of the rotor and / or the cover plate on the second end face of the rotor have fastening devices, through which torque can be transmitted from the rotor to the rotor flange, and via the rotor flange, torque can be introduced into the rotor shaft. In another preferred embodiment variation of the invention, the fastening devices may also include fastening openings equidistantly arranged on a circular path. In this way, a preferred connection with the flange can be established, wherein the screws connecting the flange to the rotor then pass through the fastening openings in a torque-transmitting manner.

[0091] It is also advantageous to further improve the invention such that the cover disks on the first end face of the rotor and / or the cover disks on the second end face of the rotor have curvatures pointing inward into the rotor. The advantages of these curvatures are particularly based on the localized transfer and release of stress within the cover disks.

[0092] In another preferred embodiment of the subject matter of the invention, the cover plate on the first end face of the rotor and / or the cover plate on the second end face of the rotor may be provided with an average axial extension that corresponds to 1% to 80% of the axial extension of the magnetic element, which has proven to be particularly advantageous for the desired axial stiffness of the rotor.

[0093] Finally, the invention can also be advantageously designed such that the cover disk on the first end face of the rotor and the cover disk on the second end face of the rotor are substantially the same, which can have a positive impact on the manufacturing cost of the rotor due to the increased proportion of identical parts.

[0094] However, the cover disks on the first end face of the rotor and the cover disks on the second end face of the rotor may also be made of different materials and / or have different geometries.

[0095] The cover plates on the first and / or second end faces of the rotor can be specifically designed according to fire protection requirements and thus serve as protective layers for other components of the rotor. This means, for example, that the rotor can meet overall fire protection requirements, while the individual components hidden beneath the cover plates do not necessarily need to directly meet such requirements.

[0096] Inner Ring According to another preferred embodiment of the invention, the rotor for an axial flux machine, particularly for an axial flux machine in the transmission system of a motor vehicle, has a plurality of magnetic elements arranged circumferentially distributed in the rotor, wherein the magnetic elements are radially supported on an inner ring.

[0097] The inner ring can also be formed, for example, by a rotor shaft, such that the magnetic element is radially inwardly supported on the rotor shaft serving as the inner ring.

[0098] Furthermore, the magnetic element can be at least partially directly radially supported on the inner ring, or at least partially indirectly supported on the inner ring, for example, via contact ribs radially formed between the inner ring and the magnetic element. The contact ribs can be specifically designed as a single piece with the inner ring.

[0099] This has the following advantages: the partially assembled components of the rotor can be processed together via the inner ring during the manufacturing process.

[0100] In this case, for example, by connecting the corresponding processing tool to the inner surface of the inner ring, the inner surface of the inner ring can be reused as a receiving part for processing.

[0101] Similarly, the inner ring can utilize external prestress to help provide the least possible resistance to the circumferential prestress of the rotor, allowing the prestress to generate circumferential residual stress. Therefore, the inner ring is an inner contour with lower stiffness, which allows for prestressing of the rotor in the circumferential direction, for example, by means of a banding element, or allows for the generation of circumferential residual stress due to the prestress.

[0102] The inner ring also allows for individual tolerance increases for as many other rotor components as possible. The inner ring allows for "buffering" of component tolerances. For example, once the stiffness-defined components have been installed together in the rotor, but before the shaft is pressed in, the inner diameter of the rotor or the inner ring can be adjusted to a common target size. Therefore, the inner ring can also define the rotor's inner diameter very precisely.

[0103] The inner ring can be connected to other parts of the rotor as a separate component, or it can be manufactured as a component shared with them.

[0104] The inner ring can be formed by machining, pressing, injection molding, or potting with filled or unfilled, reinforced or unreinforced polymer. The inner ring can be directly attached to the contact ribs and / or reinforcing pillars in the initial forming process or can be subsequently attached to the contact ribs and / or reinforcing pillars. In particular, the inner ring can also be cut from an extruded profile and attached to the rotor.

[0105] Advantageously, the inner surface of the inner ring has contour and / or shape-fitting devices, by means of which the rotor can be received in a circumferentially defined manner in, for example, a processing tool.

[0106] According to an advantageous embodiment of the invention, the rotor may be provided with an outer ring arranged coaxially with the inner ring, on which the magnetic elements are supported radially outward.

[0107] According to another preferred embodiment of the invention, a plurality of contact ribs may further be provided, each extending radially outward from the inner ring, and a plurality of magnetic elements supported on the contact ribs. This allows the magnetic elements to be fixed to the contact ribs in the radial and / or axial and / or circumferential directions. For this purpose, the contact ribs on the contact surfaces of the magnetic elements may have corresponding profiles.

[0108] Preferably, the contact rib has a V-shaped profile cross-section, wherein the tip of the V-shaped profile is oriented radially inward.

[0109] Furthermore, according to an equally advantageous embodiment of the invention, the number of contact ribs can be specified to correspond to the number of magnetic elements. The advantageous effect of this embodiment is based on the fact that it allows for particularly precise and adjustable support of the magnetic elements.

[0110] According to another particularly preferred embodiment of the invention, the plurality of contact ribs may be provided with openings axially passing through the respective contact ribs. This allows the contact ribs to be connected, for example, to the rotor flange, so as to transmit torque from the rotor to the rotor flange via the contact ribs.

[0111] Furthermore, the invention can be further improved such that reinforcing supports extending radially between the inner and outer rings are arranged between each pair of circumferentially adjacent contact ribs. The advantage of this embodiment is that vibration behavior occurring during rotor operation can be better compensated for by the rotor components subjected to centrifugal forces.

[0112] In another preferred embodiment of the invention, the inner ring and the contact rib may be integrally formed, particularly monolithically. This simplifies the production of the inner ring and the contact rib. According to another preferred embodiment of the subject matter of the invention, the inner ring may also be formed by an extrusion method.

[0113] It may also be advantageous to further improve the invention such that the inner ring is made of a material having an elastic modulus of less than 47 GPa. The advantage of this approach is that the circumferential prestress accumulates within the rotor disk structure and is less obstructed by the ring.

[0114] More preferably, the axial extension of the inner ring corresponds to at least 20% of the axial extension of the rotor.

[0115] Finally, the invention can also be advantageously designed such that the inner ring can be removed from the rotor. Thus, for example, the inner ring can be removed before the rotor shaft is pressed in. Therefore, it is particularly preferred that the contact ribs remain in the rotor when the inner ring is removed.

[0116] In principle, the inner ring can also be used as a protective element for radially external components, such as the end face of a support column facing the rotor shaft.

[0117] In this configuration, the inner ring may preferably have clearance relative to the rotor shaft. In particular, the inner ring does not transmit any torque to the rotor shaft via its inner surface.

[0118] Contact Rib Preferably, the rotor for an axial flux machine, particularly for an axial flux machine in the drivetrain of a motor vehicle, may include a plurality of magnetic elements arranged circumferentially in the rotor, wherein the magnetic elements are radially inwardly supported on a plurality of contact ribs.

[0119] This provides the following advantage: the torque generated at the magnetic element can be at least partially transmitted to the rotor shaft via the contact ribs.

[0120] For this purpose, the torque generated by the magnetic element is directed to the contact ribs, and then transmitted to the rotor shaft via the contact ribs, for example, through the inserted rotor flanges. Alternatively, some of the torque (radial) can be transmitted directly to the rotor shaft via the contact ribs, or some of the torque (radial) can be transmitted to the rotor shaft via the inserted inner ring. This can be achieved, for example, through friction engagement and / or form fit and / or material bonding. Similarly, the contact ribs can transmit torque to components or a chain of components, which then transmit the torque to the shaft.

[0121] Furthermore, during rotor operation, the contact ribs provide support against axial tilting of the magnetic element. This also allows the magnetic element to be fixed to the contact ribs in the radial and / or axial and / or circumferential directions. For this purpose, the contact ribs on the contact surface of the magnetic element can have a corresponding profile.

[0122] Furthermore, the contact rib supports within the rotor form a load path that can be prestressed primarily under compressive stress from the rotor shaft to the magnetic elements and then to the bandage elements. This particularly allows for minimizing the stress amplitude within this path.

[0123] Preferably, the contact rib has a V-shaped profile cross-section, wherein the tip of the V-shaped profile is oriented radially inward.

[0124] The contact ribs can be designed as a one-piece or multi-piece design.

[0125] The contact rib should preferably be designed such that the contact rib has a radial extension that corresponds to at least 48% of the radial extension between the radial outer edge of the rotor shaft and the radial outer edge of the magnetic element.

[0126] The contact ribs can be connected to other components of the rotor. The contact ribs can be provided as separate components in the rotor. Multiple contact ribs, preferably all contact ribs, can also be connected to each other, for example, via an inner ring.

[0127] Contact ribs can be produced by machining, pressing, injection molding, or potting with filled or unfilled, reinforced or unreinforced polymers. Contact ribs can also be made of non-magnetic steel or ceramic.

[0128] The contact ribs can be directly attached to the magnetic element and / or rotor shaft during the initial forming process, or they can be subsequently attached to the magnetic element and / or rotor shaft. Furthermore, the contact ribs can be connected to single-layer or multi-layer joints on the shaft side and magnet side.

[0129] According to an advantageous embodiment of the invention, the number of magnetic elements can be specified to correspond to the number of contact ribs, which can help to provide particularly good support for the magnetic elements. However, in principle, it is also conceivable to provide contact ribs for contacting multiple magnetic elements or multiple contact ribs for use with each magnet.

[0130] According to another preferred embodiment of the invention, the plurality of contact ribs may also be provided with openings axially passing through the respective contact ribs. This allows the contact ribs to be connected, for example, to the rotor flange, so as to transmit torque from the rotor to the rotor flange via the contact ribs.

[0131] Furthermore, according to an equally advantageous embodiment of the invention, at least one reinforcing bracket extending radially can be arranged between each pair of circumferentially adjacent contact ribs. The advantage of this embodiment is that vibration behavior occurring during rotor operation can be better compensated for by the rotor components subjected to centrifugal forces.

[0132] According to another particularly preferred embodiment of the invention, a plurality of contact ribs may be provided, each extending radially outward from the inner ring. In this way, the inner ring can, by means of external prestress, help to provide as little resistance as possible to the circumferential prestress of the rotor, so that the prestress can generate circumferential residual stress. Thus, the inner ring has an inner contour with low stiffness, which allows, for example, prestressing of the rotor in the circumferential direction by a bandage element, or allows the generation of circumferential residual stress due to the prestress. Furthermore, for example, by attaching a corresponding processing tool to the inner surface of the inner ring, the inner surface of the inner ring can be reused as a receiving portion for processing.

[0133] Furthermore, the invention can be further improved such that multiple contact ribs, preferably all contact ribs, are formed substantially identically. The resulting improved rotor uniformity particularly allows for reduced manufacturing costs.

[0134] In another preferred embodiment of the invention, it may be specified that the multiple contact ribs are formed of plastic, particularly fiber-reinforced plastic, non-magnetic steel or ceramic.

[0135] It may also be advantageous to further improve the invention so that the contact ribs are formed from extruded profiles. This simplifies the production of the contact ribs and inner rings (if any).

[0136] In another preferred embodiment of the subject matter of the invention, the contact ribs may be defined as being formed by stamping and stacking laminations.

[0137] Finally, the invention can also be advantageously designed such that at least one contact rib has a form-fitting device on its radially inwardly pointing surface toward the rotor shaft, via which a torque transmission connection can be established between the rotor shaft and the contact rib. The resulting advantage is particularly in providing precise positioning of the rotor shaft and the contact rib relative to each other.

[0138] Outer Ring Particularly preferably, the rotor for an axial flux machine, especially for an axial flux machine in the transmission system of a motor vehicle, comprises a plurality of magnetic elements arranged circumferentially in the rotor, wherein the magnetic elements are radially outwardly supported on an outer ring.

[0139] This support can be direct or indirect. In the case of direct support, the magnetic element rests at least partially against the outer ring. In the case of indirect support, a layer of material is still at least partially maintained between the magnetic element and the outer ring.

[0140] This has the following advantages: the typically very brittle magnetic elements can be better protected from mechanical influences, and the load caused by centrifugal force can be transmitted evenly during rotor operation. Therefore, these forces caused by the magnetic elements can be evenly transmitted over a wider circumferential area of ​​the outer ring to other parts of the rotor, such as the bandage elements.

[0141] Therefore, preferably, the outer ring provides a "cushioning layer" for the magnetic element to effectively protect the brittle material of the magnetic element, thereby avoiding unwanted stress peaks. Thus, the outer ring can preferably conform to the magnetic element, which can be achieved in terms of manufacturing, for example, through injection molding processes and / or via bonding layers such as adhesives and / or via a material having an elastic modulus lower than that of the material of the magnetic element. This allows the forces exerted by the magnetic element to be distributed over the largest possible contact area, thereby reducing localized compressive stress.

[0142] In addition, the outer ring can increase the axial stiffness of the rotor.

[0143] The outer ring can be produced by injection molding or by potting with filled or unfilled, reinforced or unreinforced polymers. It is also conceivable that the outer ring be formed from non-magnetic steel or ceramic.

[0144] According to an advantageous embodiment of the invention, the annular bandage element may be positioned on the outer ring by a press fit, such that prestress is introduced into the rotor via the bandage element.

[0145] This allows the bandage element to be protected from direct contact with the typically very rough magnetic element. Therefore, the outer ring separates the brittle, rough magnetic element from the bandage element, which is generally relatively sensitive to notches.

[0146] Furthermore, the outer ring can provide a uniform padding layer on the outer surface of the bandage element, which simplifies the pressing process and ensures uniform load transfer within the bandage element. Additionally, it can reduce or completely eliminate localized (excessive) stress in the lateral direction of the bandage element. The outer ring also provides a uniform outer surface on which the bandage element can be pressed. This surface can also be precisely dimensionally machined prior to the press-fit process, allowing for adjustment of the coverage area of ​​the press-fit bandage element.

[0147] Therefore, the outer ring locally absorbs and concentrates the forces generated by the magnetic elements and / or reinforcing struts during rotor operation, and transmits these forces evenly to the bandage elements over a large area.

[0148] According to another preferred embodiment of the invention, the outer ring may also be specified to be circumferentially closed, which is particularly advantageous from a manufacturing point of view and also advantageous relative to the axial stiffness of the rotor.

[0149] Furthermore, according to an equally advantageous embodiment of the invention, the outer ring can be defined as being formed from individual ring segments. In this case, in particular, the ring segments of the outer ring and the magnetic elements can form structural units, which are then formed into a ring by circumferentially arranging a plurality of these structural units.

[0150] Therefore, the outer ring can be formed as a closed loop or from ring segments arranged to form a ring. The outer ring can be formed by rolling a stamped strip or by cutting an extruded profile. Furthermore, it is conceivable that the outer ring can be stamped from a sheet to form a longitudinal structure and unfold in a fan shape.

[0151] According to another particularly preferred embodiment of the invention, the outer ring may include a plurality of recesses, each of which has a contact surface for the magnetic element extending in the circumferential direction, and each recess has a connecting portion extending radially inward from the outer ring on two sides of the magnetic element in the circumferential direction. This enables improved guidance and positioning of the magnetic element in the circumferential direction. Furthermore, the recesses facilitate rotor production because, for example, the magnetic element can be positioned in a predetermined position relative to the outer ring via the recesses prior to injection molding or potting processes.

[0152] Furthermore, the invention can be further improved such that at least one reinforcing support is arranged between each pair of circumferentially adjacent magnetic elements, the reinforcing support extending radially toward the outer ring, thereby allowing the load path to be transmitted to the outer ring in a defined manner via the reinforcing support.

[0153] In another preferred embodiment of the invention, it may be further specified that a plurality of reinforcing struts are each supported radially on the outer ring, thereby preventing the reinforcing struts from tilting. This also allows the forces of the reinforcing struts to be transmitted particularly evenly to the bandage element. This positively contributes to the overall axial stiffness of the rotor disc.

[0154] It is also advantageous to further improve the invention so that at least one reinforcing bracket is supported on the connecting portion of the outer ring in the radial direction, which can further improve the force transmission between the reinforcing support and the outer ring.

[0155] Multiple reinforcing struts can also be supported radially on the connecting part of the outer ring.

[0156] In another preferred embodiment of the subject matter of the invention, the outer ring may be formed by an extrusion method, which is particularly advantageous in terms of production technology.

[0157] Finally, the invention can also be advantageously designed such that the outer ring has a polygonal circumferential outer profile with multiple support points. It has been shown that if the outer ring is polygonal along its load introduction point and support points, the outer ring has advantageous stiffness and can absorb the corresponding load particularly well.

[0158] In this context, it is particularly preferable that the support points of the polygonal profile are determined by the load-introducing element. Therefore, the shape during loading is predicted in the unloaded structure, leading to an increase in initial stiffness.

[0159] Strengthen the pillar A rotor for an axial flux machine, particularly for an axial flux machine in the transmission system of a motor vehicle, preferably comprises an inner ring and an outer ring arranged coaxially with the inner ring, and magnetic elements arranged between the inner and outer rings. Reinforcing struts extending radially are arranged in a spoke-like manner between the inner and outer rings, and one magnetic element is arranged circumferentially on each side of the reinforcing strut, operatively connected to the reinforcing strut such that during rotor operation, a force component caused by centrifugal force acting on the magnetic element can be transmitted from the magnetic element to the reinforcing strut, and / or a force component generated by centrifugal force acting on the reinforcing strut can be transmitted from the reinforcing strut to the magnetic element. At least one reinforcing strut and / or at least one magnetic element is connected to at least one cover plate, which at least partially covers the rotor on a first end face, such that during rotor operation, force can be transmitted from one reinforcing strut and / or at least one magnetic element to the at least one cover plate, and / or force can be transmitted from the at least one cover plate to one reinforcing strut and / or at least one magnetic element.

[0160] On the one hand, this can increase the axial stiffness of the rotor. Furthermore, the rotor according to the invention can more uniformly direct the centrifugal load of the magnetic elements radially outward, for example, by introducing an outer ring and / or bandage element.

[0161] The inner ring can also be formed, for example, by a rotor shaft, such that the magnetic element is radially inwardly supported on the rotor shaft serving as the inner ring.

[0162] In addition, the reinforcing support can be in direct contact with the bandage, either partially or completely.

[0163] Furthermore, the cover plate allows for the provision of uniform contact surfaces for contact and absorption of operating forces, such as through flanges. The flanges can advantageously be connected to the cover plate via tightly tolerant contact surfaces to uniformly and safely absorb the generated operating forces. For example, the cover plate can also disperse stress peaks caused by rotor inhomogeneities over a larger area, and thus reduce stress peaks.

[0164] Furthermore, the cover plate, due to its uniform, particularly flat, surface, can have a beneficial effect on acoustic and aerodynamic friction during rotor operation. In the event of contact between the rotor and stator, the cover plate can also minimize the effects of contact and wear on rotor functional components. The cover plate can also act as a wear element in the contact between the rotor and stator. On the one hand, this serves to protect the internal structure; on the other hand, the cover plate can be locally treated to minimize the effects of friction, for example by means of: a sliding layer for reducing energy input; a localized wear-resistant layer; and / or a sensor in the contact area that detects the initiation of contact.

[0165] Preferably, the reinforcing struts extending radially between the inner and outer rings are arranged in a spoke-like manner, wherein a magnetic element is arranged between each pair of circumferentially adjacent reinforcing struts.

[0166] According to an advantageous embodiment of the invention, it can be specified that on both sides of each reinforcing strut, a connecting element is arranged in the circumferential direction between one of the magnetic elements and the corresponding reinforcing bracket, wherein the connecting element is formed of a material different from the material of the inner ring and / or outer ring and / or magnetic element and / or reinforcing strut.

[0167] According to another preferred embodiment of the invention, it can be specified that at least one of the reinforcing pillars is formed in multiple parts. It can also be specified that multiple reinforcing pillars are composed of multiple components. Furthermore, all reinforcing pillars can be composed of multiple parts.

[0168] Furthermore, according to an equally advantageous embodiment of the invention, it can be specified that at least one of the reinforcing struts is integrally formed with the inner ring and / or outer ring. It is also preferable that multiple reinforcing struts are integrally formed with the inner ring and / or outer ring. Most preferably, all reinforcing struts are integrally formed with the inner ring and / or outer ring.

[0169] The reinforcing strut can be directly inserted into the rotor in a single molding process, or it can be subsequently arranged in the rotor. The reinforcing strut can be at least partially re-machined before and after installation into the rotor.

[0170] According to another particularly preferred embodiment of the invention, it may be specified that, within the radial extension of the reinforcing bracket, at least one material of at least one reinforcing bracket has an elastic modulus greater than 6000 MPa. It is also preferred that, within the radial extension of the reinforcing struts, at least one material of at least one of the reinforcing struts has an elastic modulus greater than 6000 MPa. Furthermore, it is even more preferred that, within the radial extension of the reinforcing bracket, at least one material of at least one of the reinforcing struts has an elastic modulus greater than 6000 MPa.

[0171] Furthermore, the invention can be further improved such that at least one of the reinforcing pillars is formed of plastic, particularly fiber-reinforced plastic, non-magnetic steel, aluminum, or ceramic.

[0172] Particularly preferred is that the material of one of the reinforcing struts is different from the material of the connecting element and / or the inner ring and / or the outer ring and / or the magnetic element.

[0173] Reinforcing struts can be produced by machining, pressing, winding, injection molding, potting, wet winding, or pre-impregnation using filled or unfilled, reinforced or unreinforced polymers. The reinforcement can be spherical, short fiber, long fiber, or continuous fiber, or a mixture thereof.

[0174] In another preferred embodiment of the invention, it may also be specified that the reinforcing strut, magnetic element and / or inner ring have a prestress that reacts with the load bandage and / or auxiliary bandage at the operating point of the rotor.

[0175] Another advantage of this invention is that at least one of the reinforcing pillars is cubical. Preferably, multiple reinforcing pillars are cubical. Most preferably, all reinforcing pillars are cubical.

[0176] In another preferred embodiment of the subject matter of the invention, it can be specified that a plurality of reinforcing struts, preferably all reinforcing struts, are substantially identical, which is particularly advantageous in terms of manufacturing cost.

[0177] Finally, the invention can also be advantageously designed such that at least one of the reinforcing struts is connected to a cover plate on one of its axial surfaces, the cover plate at least partially covering the rotor on one end face of the rotor. It is also preferable herein that each of the plurality of reinforcing struts is connected to a cover plate on one of its axial surfaces, the cover plate at least partially covering the rotor on one end face of the rotor. It is also highly preferred that all reinforcing struts are each connected to a cover plate on one of its axial surfaces, the cover plate at least partially covering the rotor on one end face of the rotor.

[0178] In particular, the above advantages are that the reinforcing strut allows the shear field to be transmitted to the cover plate and / or the cover plate allows the shear field to be transmitted to the reinforcing strut. Attached Figure Description

[0179] In the following description, the invention will be given in more detail with reference to the accompanying drawings, without limiting the general concept of the invention.

[0180] In the attached diagram: Figure 1 A perspective view of the rotor used in an axial flux machine is shown. Figure 2 An exploded view of the rotor used in an axial flux machine is shown. Figure 3 A cross-sectional view of the rotor of an axial flux engine is shown. Figure 4 It shows Figure 3 Detailed cross-sectional view of the rotor shown. Figure 5 The individual reinforcing struts, outer rings, and bandage elements are shown in a 3D view. Figure 6 The outer ring is shown in cross-sectional view. Figure 7 A detailed view of the contact surface of the outer ring is shown in cross-section. Figure 8 A detailed view of the connecting elements in the rotor is shown in cross-section. Figure 9 The rotors in three different manufacturing states are shown in cross-sectional views. Figure 10 A first embodiment of the magnetic element is shown in cross-sectional view. Figure 11 A first embodiment of the magnetic element is shown in a perspective view. Figure 12 A second embodiment of the magnetic element is shown in a perspective view. Figure 12A third embodiment of the magnetic element is shown in a perspective view. Figure 14 A fourth embodiment of the magnetic element is shown in a perspective view. Figure 15 Two embodiments of the bandage element are shown in three-dimensional cross-sectional views. Figure 16 The rotor is shown in a three-dimensional axial cross-sectional view. Figure 17 The rotor with the cover disk is shown in axial cross-section. Figure 18 The cross-sectional view shows the insulating inner ring with contact ribs and the magnetic element. Figure 19 The rotor without an inner ring is shown in cross-sectional view. Figure 20 Two embodiments of the axial flux engine are illustrated with schematic axial cross-sectional views. Figure 21 A schematic diagram illustrates a motor vehicle with an axial flux engine. Detailed Implementation

[0181] Figure 1 and Figure 2 The rotor 1 for an axial flux motor 2 is shown, particularly for an axial flux motor 2 located within the transmission system 3 of a motor vehicle 4, as also... Figure 21 As depicted in the text.

[0182] The rotor 1 includes an inner ring 5 and an outer ring 6 arranged coaxially with the inner ring. Reinforcing struts 7 with rectangular cross-sections are arranged in a spoke-like manner, extending radially between the inner ring 5 and the outer ring 6. Magnetic elements 8 are arranged between each pair of circumferentially adjacent reinforcing struts 7.

[0183] As from Figure 3 As can be clearly seen, on both sides of each reinforcing support 7, a connecting element 9 is arranged circumferentially between a magnetic element 8 and the corresponding reinforcing bracket 7. The connecting elements 9 are basically the same.

[0184] The connecting element 9 is formed of a different material than the inner ring 5 and / or the outer ring 6 and / or the magnetic element 8 and / or the reinforcing strut 7 and / or the contact rib 60.

[0185] The magnetic element 8 is radially received on the outside by a closed outer ring 6. An annular auxiliary bandage 12 and an annular load bandage 17 are connected to the outer ring. The magnetic element 8 rests radially inward on the inner ring 5 via contact ribs 60, which is connected to the rotor shaft 23 via a flange 16. Cover discs 18 and 19 are axially attached to both sides. The flange 16 receives the inner ring 5 or the contact ribs 60 and is connected to the flange ring 20 by screws. A compression limiter 21 supports the inner ring 5 and acts as a screw support element.

[0186] The connecting element 9 compensates for the relative displacement between the magnetic element 8 and other components, and simultaneously reduces the normal tensile stress on the connecting element 9. Simultaneously, the connecting element 9 transfers the centrifugal force of the magnetic element 8 to the reinforcing strut 7, and thus, among other things, reduces the load on the cover layer. The connecting element 9 axially connects the cover layer, i.e., the cover discs 18, 19, to the rotor 1 to maintain a stable air gap between the rotor 1 and the stator 22. Furthermore, the connecting element 9, together with the prestressed bandage (before the shaft is pressed in), allows the rotor 1 to withstand circumferential pressure. For this purpose, an annular auxiliary bandage 12 is applied to the outer ring 6. The elasticity of the connecting element 9 defines the circumferential stiffness of the rotor 1, or adjusts that circumferential stiffness to the desired level in a targeted manner.

[0187] Figures 3 to 4 A rotor 1 with an inner ring 5 is shown, with reinforcing struts radially supported on the inner ring. However, if the rotor 1 is mounted on the rotor shaft 26 in a manner fixed in terms of rotation, then... Figures 3 to 4 The inner ring 5 can also be removed before being mounted onto the rotor shaft 26, for example, by milling, so that in the mounted state, the inner ring 5 is formed from the outer surface of the rotor shaft 26. This is in Figure 19 As shown in the figure, the reinforcing strut 7 is directly radially supported on the rotor shaft 26.

[0188] Rotor 1 can be used as follows Figure 20 The structure shown in figure a is H-shaped or in Figure 20 b shows the axial flux engine 2 with an I-shaped structure.

[0189] Figure 4 It shows from Figure 3 A detailed view of the known rotor 1. Here, the inner ring 5 and the outer ring 6 arranged coaxially with the inner ring can also be clearly seen, wherein the reinforcing struts 7 extending radially between the inner ring 5 and the outer ring 6 are arranged in a spoke-like manner, and magnetic elements 8 are arranged between each pair of circumferentially adjacent reinforcing struts 7.

[0190] The annular bandage element 44 rests against the outer ring 6 via a press fit, allowing prestress to be introduced into the rotor 1 through the bandage element 44. The bandage element 44 can completely or partially cover the outer ring 6 of the rotor 1 in the axial direction. The bandage element 44 is designed as multiple parts, wherein at least one annular auxiliary bandage 12 rests on the outer ring 6, and at least one annular load bandage 17 rests on the auxiliary bandage 12. In principle, the bandage element 44 can also be designed as a single part. Furthermore, the auxiliary bandage 12 can be applied only via an interference fit, and the load bandage 17 can be positioned on the auxiliary bandage without any load. Of course, the auxiliary bandage 12 and the load bandage 17 can also be arranged via an interference fit.

[0191] The following reference Figure 8 A more detailed explanation of the connecting element 9 of rotor 1 is provided. Connecting element 9 compensates for the relative displacement between magnetic element 8 and other components, while simultaneously reducing normal tensile stress on connecting element 9. Simultaneously, connecting element 9 transfers the centrifugal force of magnetic element 8 to reinforcing strut 7, and thus, among other things, reduces the load on the cover layer. Connecting element 9 axially binds the cover layer, i.e., cover discs 18, 19, to rotor 1 to maintain a stable air gap between rotor 1 and stator 22. Furthermore, connecting element 9, together with the prestressed bandage (before the shaft is pressed in), allows rotor 1 to withstand circumferential pressure. For this purpose, an annular auxiliary bandage 12 is applied to the outer ring 6. The elasticity of connecting element 9 defines the circumferential stiffness of rotor 1, or adjusts that circumferential stiffness to a desired level in a targeted manner.

[0192] The connecting element 9 is preferably made of a material with an elastic modulus between 400 MPa and 46000 MPa, and exhibits elastic properties during the operation of the rotor 1.

[0193] like Figure 8 As shown, the connecting element 9 is rod-shaped and has an average thickness 10 of at least 0.47 mm, preferably 0.5 mm to 10 mm, and particularly preferably 0.5 mm to 5 mm in the circumferential direction. Furthermore, the connecting element 9 has a connecting portion 13 within the region of the magnetic element 8, which deviates from the rod shape and partially rests on one of the magnetic elements 8. The reinforcing struts 7 are cubic, wherein each connecting element 9 at least partially rests on the longitudinal surface 11 of one of the reinforcing struts 7.

[0194] Figure 9A possible method of manufacturing rotor 1 is shown. Rotor 1 is manufactured by equipping the tool with at least magnetic elements 8, and compression restraints 21 and reinforcing struts 7 may be added to the magnetic elements in particular. Subsequently, in one or more steps, the outer ring 6 and contact ribs 60, including the inner ring 5 which may only be temporarily present, are overmolded, pressed, or connected. Covering discs 18, 19 can then be applied, and any remaining filling areas can be filled with a filling compound. Before pressing into rotor shaft 23, rotor 1 can be circumferentially prestressed via auxiliary bandage 12. Load bandage 17 located radially outside of auxiliary bandage 12 can also optionally be prestressed. The central hole and shaft receiving portion are then formed by removing most or all of the inner ring 5. Pressing rotor shaft 23 with flange 16 axially fixed constitutes engagement with rotor 1. Rotor 1 is balanced during balancing processes on flange 16, flange disc 20, outer ring 6, or connecting element 9.

[0195] Therefore, as explained again, the first method for producing the rotor 1 used in the axial flux machine 2 may include the following steps: first, providing a molding tool 14, a plurality of reinforcing struts 7, and a plurality of magnetic elements 8.

[0196] Then, the reinforcing struts 7 and magnetic elements 8 are arranged in the molding tool 14, such that the reinforcing struts 7 are positioned in a spoke-like manner, and the magnetic elements 8 are arranged between each pair of circumferentially adjacent reinforcing struts 7, wherein, in the molding tool 14, an air gap 15 is provided on both sides of each reinforcing strut 7 between one of the magnetic elements 8 and the corresponding reinforcing strut 7. This can be achieved... Figure 9 The manufacturing status can be seen in section a.

[0197] Subsequently, injection molding is performed using molding tool 14 to form the inner ring 5 and the outer ring 6, thereby fixing the positions of the reinforcing strut 7, the magnetic element 8, the inner ring 5, and the outer ring 6 relative to each other. Figure 9 It is shown in b.

[0198] Now, the air gaps 15 on both sides of one of the reinforcing pillars 7 are filled with a material different from the material of the inner ring 5 and / or the outer ring 6 and / or the magnetic element 8 and / or the reinforcing pillar 7, so that a connecting element 9 is formed between one of the magnetic elements 8 and the corresponding reinforcing support 7. The filling can be performed by an injection molding process or a casting process in the molding tool 14. However, the filling can also be performed only after one or both cover plates 18, 19 have been applied.

[0199] Alternatively, molding tool 14, multiple reinforcing struts 7, multiple magnetic elements 8 and multiple connecting elements 9 may be provided first, the connecting elements being made of a different material than the inner ring 5 and / or the outer ring 6 and / or the magnetic elements 8 and / or the reinforcing struts 7.

[0200] Therefore, firstly, the reinforcing struts 7 and magnetic elements 8 are arranged in the molding tool such that the reinforcing struts 7 are positioned in a spoke manner, and the magnetic elements 8 are arranged between each pair of circumferentially adjacent reinforcing struts 7, and wherein, in the molding tool 14, on both sides of each reinforcing strut 7, an air gap 15 is provided between one of the magnetic elements 8 and the corresponding reinforcing support 7.

[0201] Then, the inner ring 5 and outer ring 6 are injection molded using molding tool 14, so that the positions of the reinforcing strut 7, magnetic element 8, inner ring 5, and outer ring 6 relative to each other are fixed. Finally, the connecting element 9 is inserted into the air gap 15 on both sides of one of the reinforcing struts 7.

[0202] Then Figure 9 c shows the rotor 1 with the connecting element 9 inserted.

[0203] Rotor 1 can be used as follows Figure 9 The a shown is in an H-shaped configuration or in Figure 9 The axial flux engine 2 with an I-shaped configuration is shown in b.

[0204] Figure 10 A magnetic element 8 for a rotor 1 of an axial flux engine 2 is shown, wherein the magnetic element 8 has a longitudinal extension 24 and a continuous circumferential profile 25.

[0205] When the magnetic element 8 is installed in the rotor 1, a flat first surface portion 27 extending in the longitudinal direction and a flat second surface portion 28 extending in the longitudinal direction are formed on the first side 26 facing the first rotation direction of the rotor 1. When the magnetic element 8 is installed in the rotor 1, the first surface portion 27 is radially positioned above the second surface portion 28.

[0206] exist Figure 10 In the embodiment shown, the magnetic element 8 is formed in a mirror-symmetrical manner with respect to its longitudinal extension 24. Therefore, when the magnetic element 8 is installed in the rotor 1, a flat third surface portion 30 extending in the longitudinal direction and a flat fourth surface portion 31 extending in the longitudinal direction are formed on the second side 29 facing the second rotation direction of the rotor 1, wherein the third surface portion 30 is radially positioned above the fourth surface portion 31 when the magnetic element 8 is installed in the rotor 1.

[0207] The surface portions 27, 28, 30, and 31 are arranged and shaped such that when the magnetic element 8 is mounted in the rotor 1, a first plane 32 extending through the first surface portion 27 and a third plane 33 extending through the third surface portion 30 intersect radially above the magnetic element 8 in the direction of the longitudinal extension 24, and when the magnetic element 8 is mounted in the rotor 1, a second plane 34 extending through the second surface portion 28 and a fourth plane 35 extending through the fourth surface portion 31 intersect radially below the magnetic element 8 in the direction of the longitudinal extension 24.

[0208] The flat first surface portion 27 and the flat third surface portion 30 have a length of at least 2 mm and at most 48 mm in the circumferential direction of the magnetic element 8. The flat first surface portion 27 and the flat third surface portion 30 can be used for sealing during the manufacture of the rotor 1, for radial positioning in the tool, and as reference surfaces (relative to the centroid of the geometry) for magnetic sorting.

[0209] Figure 10 It is also shown that the circumferential profile 25 has a fifth surface portion 39, which, when mounted in the rotor 1, is radially outwardly oriented and connects the first surface portion 27 to the third surface portion 30. The fifth surface portion 39 has an arcuate profile with a rotation axis extending coaxially with the rotation axis of the rotor 1. Therefore, the magnetic element 8 has a substantially arcuate profile on its radially outer surface, the center of which is concentric with the rotation axis of the rotor 1. Due to this profile, the (centrifugal) load generated by the magnetic element 8 is uniformly transmitted to the radially outer component regions (e.g., auxiliary bandage 12 or load bandage 17). Furthermore, the magnetic element 8 uniformly supports these outer regions.

[0210] As from Figure 10 It is also evident that the magnetic element 8 has an upper region 42 and a lower region 43, wherein the upper region 42 extends upward by half of the longitudinal extension 24 of the magnetic element 8, and the lower region 43 extends downward by half of the longitudinal extension 24 of the magnetic element 8. The first surface portion 27 and the third surface portion 30 extend only within the upper region 42 of the magnetic element 8.

[0211] from Figure 11 As can be seen in the illustrated embodiment, the circumferential profile 25 may have a chamfer 36 formed at the transition between the circumferential profile 25 and the axial surface 37. In this example, the chamfer 36 extends circumferentially around the circumferential profile 25. The chamfer 36 can help improve the adhesion between the magnetic element 8 and adjacent components in the region of the circumferential profile 25, for example, to allow for a thicker and therefore more flexible adhesive or bonding layer relative to the magnetic element 8. The chamfer 36 may vary in its profile along the path of the chamfer portion around the circumference of the magnet.

[0212] Figure 12 An embodiment of the magnetic element 8 is shown, wherein the circumferential profile 25 has a sixth surface portion 40, which, once installed in the rotor 1, is radially inwardly oriented and connects the second surface portion 28 to the fourth surface portion 31. The sixth surface portion 40 has a chamfered portion 41 formed at the transition between the sixth surface portion 28 and the axial surface 37. This defines a wedge-shaped profile on the sixth surface portion 40, which simplifies the connection of the magnetic element 8 to, for example, the inner ring 5 of the rotor 1.

[0213] like Figures 13 to 14 As shown, the flat second surface portion 28 and the flat fourth surface portion 31 may each have a structure 38 that at least partially protrudes from or into the respective flat surface. These structures 38 are designed as profiles that provide a type of undercut in the radial direction for shape fitting in adhesive bonding or joining. Such profiles must be designed at least such that they result in an increase in the surface area for joining and optimize support for operational loads.

[0214] For example, as can be Figure 4 As can be seen, the annular bandage element 44 can be press-fitted onto the outer ring 6 of the rotor 1, so that prestress is introduced into the rotor 1 via the bandage element 44. In the illustrated embodiment, the bandage element 44 is designed as a multi-part structure, wherein at least one annular auxiliary bandage 12 rests on the outer ring 6, and at least one annular load bandage 17 rests on the auxiliary bandage 12, wherein the material of the auxiliary bandage 12 is different from the material of the load bandage 17.

[0215] At least one material of the multi-part bandage element 44, particularly the load bandage 17, has an elastic modulus greater than 48,000 MPa in the circumferential direction of the bandage element 44. In this case, the prestress introduced into the rotor 1 by the auxiliary bandage 12 is greater than the prestress introduced by the load bandage 17. The bandage element 44 can even be configured such that the load bandage 17 rests on the auxiliary bandage 12 in such a way that the load bandage does not introduce any prestress into the rotor 1.

[0216] The outer ring 6 has a polygonal circumferential outer contour 45, which has a plurality of support points 46.

[0217] The bandage element 44 can be attached to the rotor 1, for example, in the following manner: First, the rotor 1 is provided with an inner ring 5 and an outer ring 6 arranged coaxially with the inner ring, wherein reinforcing struts 7 extending radially between the inner ring 5 and the outer ring 6 are arranged in a spoke-like manner, and magnetic elements 8 are arranged between each pair of circumferentially adjacent reinforcing struts 7. Then, the annular bandage element 44 is press-fitted onto the outer ring 6, such that prestress is introduced into the rotor 1 via the bandage element 44. Finally, the rotor 1 is connected to the rotor shaft 23.

[0218] The following reference Figure 4 and Figure 5 A more detailed explanation of reinforced support 7 is provided. Figure 4 A rotor 1 is shown, which includes an inner ring 5 and an outer ring 6 arranged coaxially with the inner ring, and a magnetic element 8 arranged between the inner ring 5 and the outer ring 6, wherein a reinforcing strut 7 is arranged radially between the inner ring 5 and the outer ring 6 in a spoke-like manner.

[0219] One of the magnetic elements 8 is arranged circumferentially on both sides of the reinforcing bracket 7 and is operatively connected to the reinforcing bracket 7 such that during operation of the rotor 1, the force component caused by the centrifugal force acting on the magnetic element 8 can be transmitted from the magnetic element 8 to the reinforcing bracket 7 and / or during operation of the rotor, the force component caused by the centrifugal force acting on the reinforcing bracket can be transmitted from the reinforcing bracket to the magnetic element.

[0220] from Figure 4 It can also be seen that the connecting element 9 is arranged circumferentially on both sides of one of the reinforcing pillars 7 between one of the magnetic elements 8 and the corresponding reinforcing support 7, wherein the connecting element 9 is made of a different material than the inner ring 5 and / or the outer ring 6 and / or the magnetic element 8 and / or the reinforcing pillar 7. Within the radial extension of the reinforcing support 7, the material of the reinforcing support 7 has an elastic modulus greater than 6000 MPa.

[0221] The reinforcing strut 7 is cubic and substantially identical. The reinforcing strut 7 is connected to the cover discs 18 and 19 on at least one of its axial surfaces 50, and the cover discs at least partially cover the rotor 1 on the end face 51 of the rotor. Figure 16 It can be clearly seen in the middle.

[0222] By introducing the radial reinforcing strut 7 parallel (relative to the load direction) into the magnetic element load path, the magnetic load path can be closed via the bandage element 44, rotor shaft 23, or inner ring 5 and contact rib 60. By applying equal prestress to the components involved at the operating point of rotor 1, the reinforcing strut 7 directly contributes to increasing the overall stiffness of rotor 1. Therefore, the magnitude of the radial stress in the magnetic element, and if applicable, its connecting element 9, is reduced. Furthermore, the overall radial stiffness of rotor 1 increases (relative to magnet displacement per unit centrifugal load), which reduces the displacement amplitude and thus reduces the relative stress between the components.

[0223] Therefore, the reinforcing strut 7 introduces magnetic centrifugal loads at other points into the bandage element 444 via the outer ring 6, resulting in a more uniform and less polygonal load introduction into the bandage. Magnetic force is transmitted to the reinforcing strut 7 via load paths “magnetic element-covering disc-reinforcing strut” and “magnetic element-connecting element-reinforcing strut”. The reinforcing strut 7 then introduces the load into the bandage element 44.

[0224] The reinforcing strut 7 applies prestress to the bandage element 44 through an interference fit with the rotor shaft 23. Not only is prestress introduced into the bandage element 44, but it is also polygonized so that it can absorb operating forces more effectively (the operating point stiffness is higher than that of the original rounded bandage element 44).

[0225] The reinforcing pillar 7 is located between the two covering discs 18 and 19, which is in Figure 16 As can be clearly seen, the reinforcing strut serves as a shear field emitter for the cover discs 18 and 19 to increase their influence on axial stiffness. This influence can be further increased by partially aligning the orientation of some of the reinforcing fibers in the reinforcing strut 7 with the main load direction of the shear field. Of course, the reinforcing strut 7 also directly contributes to increasing the axial rotor stiffness through its own area moment of inertia.

[0226] For example, outer ring 6 can be Figures 6 to 7 This is clearly visible in the text and will be described in more detail below. Figure 7 A rotor 1 is shown, which includes a plurality of magnetic elements 8 arranged circumferentially in the rotor 1, wherein the magnetic elements 8 are radially outwardly supported on an outer ring 6.

[0227] The annular bandage element 44 rests against the outer ring 6 by press fitting, so that the prestress is introduced into the rotor 1 through the bandage element 44.

[0228] from Figure 6 It is clearly visible that the outer ring 6 forms a completely closed loop. In principle, it is also conceivable that the outer ring is segmented. Figure 6It is also shown that the outer ring 6 includes a plurality of recesses 70, each recess having a contact surface 71 extending in the circumferential direction for the magnetic element 8, and each of the magnetic element 8 having a connecting portion 72 extending radially inward from the outer ring 6 on both sides in the circumferential direction.

[0229] Between each pair of circumferentially adjacent magnetic elements 8, there is a reinforcing support 7 extending radially to the outer ring 6. Each of these reinforcing supports 7 is supported radially on the connecting portion 72 of the outer ring 6.

[0230] The outer ring 6 has a polygonal circumferential outer contour 45, which has a plurality of support points 46.

[0231] The following reference Figures 16 to 17 A more detailed explanation of covers 18 and 19 is provided. Figure 16 A rotor 1 is shown, which includes an inner ring 5 and an outer ring 6 arranged coaxially with the outer ring, and a magnetic element 8 arranged between the inner ring 5 and the outer ring 6, wherein a reinforcing strut 7 extending in the radial direction is arranged in a spoke manner between the inner ring 5 and the outer ring 6.

[0232] In the circumferential direction, one of the magnetic elements 8 is arranged on each side of the reinforcing bracket 7 and is operatively connected to the reinforcing bracket 7 such that during operation of the rotor 1, the force component caused by the centrifugal force acting on the magnetic element 8 can be transmitted from the magnetic element 8 to the reinforcing bracket 7 and / or during operation of the rotor, the force component caused by the centrifugal force acting on the reinforcing bracket can be transmitted from the reinforcing bracket to the magnetic element.

[0233] At least one of the reinforcing struts 7 and / or at least one of the magnetic elements 8 are connected to at least one cover plate 18, which at least partially covers the rotor 1 on the first end face 51, such that during operation of the rotor, force can be transmitted from one of the reinforcing struts 7 and / or at least one of the magnetic elements 8 to the at least one cover plate 18 and / or force can be transmitted from the at least one cover plate to one of the reinforcing struts and / or at least one of the magnetic elements.

[0234] Furthermore, at least one of the reinforcing struts 7 and / or at least one of the magnetic elements 8 are connected to at least one cover plate 19, which at least partially covers the rotor 1 on the second end face 52, such that during operation of the rotor 1, force can be transmitted from one of the reinforcing struts 7 and / or at least one of the magnetic elements 8 to the at least one cover plate 19 and / or force can be transmitted from the at least one cover plate to one of the reinforcing struts and / or at least one of the magnetic elements 8.

[0235] The cover disk 18 located on the first end face 51 of the rotor 1 and the cover disk 19 located on the second end face 52 of the rotor 1 are each formed as annular disks. The cover disk 18 located on the first end face 51 of the rotor 1 and the cover disk 19 located on the second end face 52 of the rotor 1 each have an average axial extension 58, which corresponds to 1% to 80% of the axial extension 59 of the magnetic element 8.

[0236] The cover plate 18 located on the first end face 51 of the rotor 1 and the cover plate 19 located on the second end face 52 of the rotor 1 have fastening devices 55, through which torque can be transmitted from the rotor 1 to the rotor flange 16, and through the rotor flange, torque can be introduced into the rotor shaft 23. In the illustrated embodiment, the fastening device 55 includes fastening openings 56 equidistantly arranged on a circular path. In the illustrated variant of the rotor 1 embodiment, the cover plate 18 located on the first end face 51 of the rotor 1 and the cover plate 19 located on the second end face 52 of the rotor 1 are substantially the same.

[0237] By attaching at least one cover plate 18, 19, the axial stiffness of rotor 1 increases because the cover plates 18, 19 have stiffness in their plane. Through the connection of the cover plate to rotor 1 and the load transfer via reinforcing strut 7 and / or magnetic element 8 and / or other rotor components, the shear field is transferred at least to the rotor structure, preferably to the corresponding other cover plate 18, 19. This results in an increase in the area moment of inertia, and therefore an increase in the axial stiffness of rotor 1. The cover plates 18, 19 also facilitate the transfer of centrifugal loads from magnetic element 8 via the cover plates 18, 19 to reinforcing strut 7 for the introduction of a uniform load into the outer ring 6 or bandage element 44.

[0238] The cover plates 18 and 19 also balance the forces acting on the rotor 1 in the region of the flange connection. This allows the operating force of the rotor 1 to be uniformly transmitted to the flange 16 via the contact surface. Similarly, the pressing pressure of the flange connection can be uniformly applied to the rotor 1. Any auxiliary elements, such as the knurling in the flange 16, can also be engaged in the cover plates 18 and 19.

[0239] Figure 16It is also shown that the cover plate 18 located on the first end face 51 of the rotor 1 and / or the cover plate 19 located on the second end face 52 of the rotor 1 may have a bend 57 pointing inward or outward of the rotor 1, which results in a lower overall stiffness relative to the radial rotor plane and thus allows for local decompression of the cover plates 18, 19 or the rotor 1.

[0240] The radially inner regions of the cover plates 18 and 19 that contact the flange 16 can be used as a machining layer to obtain a defined surface with the desired characteristics, thereby improving the connection with the flange 16.

[0241] Figure 17 A variation of this embodiment is shown in which a cover disc 18 located on a first end face 51 of the rotor 1 and a cover disc 19 located on a second end face 52 of the rotor 1 radially protrude beyond the edge of the outer ring 6, and the bandage element 44 rests axially on the outer ring 6 between the cover discs 18 and 19. Therefore, the cover discs 18 and 19 can be used, for example, as a direct winding structure or as an auxiliary structure for the production of the load-bearing bandage 17. The cover discs also serve to protect the bandage element.

[0242] Reference Figure 4 and Figure 18 The inner ring 5 of rotor 1 will be explained in more detail. Figure 18 A rotor 1 is shown, which includes a plurality of magnetic elements 8 arranged circumferentially in the rotor 1, wherein the magnetic elements 8 are radially inwardly supported on an inner ring 5 via contact ribs 60.

[0243] The rotor 1 also has an outer ring 6 arranged coaxially with the inner ring 5, and magnetic elements 8 are radially outwardly supported on the outer ring, such as... Figure 4 As can be seen, a reinforcing bracket 7 extending radially between the inner ring 5 and the outer ring 6 is arranged between each pair of circumferentially adjacent contact ribs 60.

[0244] Multiple contact ribs 60 extend radially outward from the inner ring 5, with the magnetic elements 8 supported radially inward on the contact ribs 60. The number of contact ribs 60 corresponds to the number of magnetic elements 8. The inner ring 5 and the contact ribs 60 are integrally formed, particularly monolithically formed. The inner ring 5 and the contact ribs 60 are formed by an extrusion method.

[0245] Therefore, the inner ring 5 also connects the internal components of the rotor 1 to facilitate their operation, particularly during the manufacturing process. Thus, the inner ring 5 provides a defined inner profile, which in the illustrated embodiment is a cylindrical inner profile, to enable the rotor 1 to be specifically received in a handling tool during the manufacturing process.

[0246] Each of the contact ribs 60 has an opening 61 that axially passes through the corresponding contact rib 60 and through which a screw passes, allowing the rotor flange 16 to be connected to the rotor 1.

[0247] As from Figure 18 It can also be clearly seen that the inner ring 5, its contact rib 60, and the magnetic element 8 supported on the contact rib are arranged in an aligned and mirror-symmetrical manner along the radially extending axis of symmetry 65.

[0248] The inner ring 5 can also be removable, or it may have already been removed from rotor 1, as can be... Figure 19 This is seen in variations of the implementation. For example, for this purpose, the inner ring 5 may have been fully machined by turning.

[0249] Now refer to Figure 4 , Figure 18 and Figure 19 The contact rib 60 is described in more detail.

[0250] Figure 4 A rotor 1 is shown, comprising a plurality of magnetic elements 8 arranged circumferentially within the rotor 1, wherein the magnetic elements 8 are radially supported on a plurality of contact ribs 60. The contact ribs 60 are thus directly or indirectly form-fitted with the corresponding magnetic elements to absorb and transmit their torque.

[0251] Furthermore, the contact rib 60 enables the rotor 1 to provide a defined axial stiffness so as to establish a force-locked (axial) frictional connection with the cover plates 18, 19, thereby axially supporting the cover plates 18, 19 and enabling the transmission of torque.

[0252] In the illustrated embodiment, the number of magnetic elements 8 corresponds to the number of contact ribs 60. Each contact rib 60 has an opening 61 that axially passes through the corresponding contact rib 60 to transmit torque to the cover discs 18, 19 and / or the rotor flange 16 and / or to enable screw connections. For this purpose, the opening may have internal threads or be designed as a through hole.

[0253] Between each pair of circumferentially adjacent contact ribs 60, a reinforcing bracket 7 extending radially is arranged, which protrudes radially outward from the inner ring 5. The contact ribs 60 are substantially the same.

[0254] The contact rib 60 between the shaft connection and the magnetic element 8 also allows for a press fit of the rotor shaft 23, achieving both an interference fit and a frictional engagement with the magnetic element 8 and the rotor shaft 23. This, in turn, enables torque to be transmitted to the rotor shaft 23.

[0255] Additionally or alternatively, form-fit details may be provided at the contact point between the contact rib and the shaft interference fit to achieve torque transmission and anti-torsional fit of the contact rib 60 on the rotor shaft 23. Therefore, at least one contact rib 60 may have a form-fitting device 63 on its radially inwardly facing surface 62 of the rotor shaft 23, via which a torque transmission connection can be established between the rotor shaft 23 and the contact rib 60. Since the contact rib 60 is directly connected to the rotor shaft 23, the rotor 1 does not have an inner ring 5. This... Figure 19 As shown in the image.

[0256] Therefore, the contact rib 60 is also used to transmit the contact rib / rotor shaft overlap by pressing it into the rotor shaft, so that the load path rotor shaft-contact rib-magnetic element-outer ring-bandage element is under favorable compressive prestress. The contact rib 60, together with the bandage element 44 and reinforcing strut 7, also serves as a radial stiffening element in the support diagram, so as to distribute the total load amplitude across the individual prestressed spring paths and thus reduce the stress amplitude in the relevant components. For this purpose, the radial stiffness of the contact rib 60 must be less than 92% of the radial stiffness of the magnetic element 8.

[0257] In all the embodiments shown, rotor 1 preferably does not contain any ferromagnetic material. Therefore, the components of rotor 1—except for magnetic element 8—preferably comprise non-ferromagnetic materials such as plastic, ceramic, non-magnetic steel, or aluminum. Most preferably, all components from the group consisting of: inner ring 5, outer ring 6, reinforcing strut 7, connecting element 9, auxiliary bandage 12, load-bearing bandage 17, cover discs 18 and 19, and contact rib 60 are made of plastic.

[0258] This invention is not limited to the embodiments shown in the accompanying drawings. Therefore, the above description is illustrative rather than restrictive. The appended claims should be understood to indicate the presence of the stated features in at least one embodiment of the invention. This does not exclude the presence of other features. Where the claims and the above description define "first" and "second" features, this designation is used to distinguish between two features of the same type, without limiting the order of priority.

[0259] List of reference numerals 1. Rotor 2 Axial flux mechanism 3. Transmission System 4 Motor vehicles 5 Inner Ring 6 Outer Ring 7. Strengthen the pillars 8 Magnetic components 9 Connecting elements 10 Thickness 11 Longitudinal Surface 12. Auxiliary bandages 13 Connection Part 14. Molding tools 15 air gap 16 flanges 17. Load-bearing bandage 18 Covering discs 19 Covering disk 20 Flange Ring 21 Compression Limiter 22 Stator 23 Rotor shaft 24. Longitudinal extension 25 Circumferential Profile 26 Side 27 Surface portion 28 Surface portion 29 Side 30 Surface portion 31 Surface portion 32 plane 33 Plane 34 Plane 35 Plane 36. Chamfered edge 37 Axial surface 38 Structure 39 Surface portion 40 Surface portion 41. Chamfered edge 42 areas 43 areas 44 Bandage Components 45. Outline 46 Support points 50 Axial surface 51 end face 52 end face 55 Fastening devices 56 Fastening devices 57. Bend 58 Extension 59 Extension 60 Contact Ribs 61 Opening 62 Surface 63 Shape-fitting components 65. Axis of symmetry 70 Depression 71 Contact Surface 72. Connection part.

Claims

1. A rotor (1) for an axial flux engine (2), particularly for an axial flux engine (2) in a transmission system (3) of a motor vehicle (4), said rotor comprising Inner ring (5); and Outer ring (6), the outer ring and the inner ring are arranged coaxially. in, A reinforcing strut (7) is arranged in a spoke-like manner, extending radially between the inner ring (5) and the outer ring (6). Furthermore, magnetic elements (8) are arranged between each pair of circumferentially adjacent reinforcing pillars (7). Its features are, On both sides of one of the reinforcing pillars (7), a connecting element (9) is arranged in the circumferential direction between one of the magnetic elements (8) and the corresponding reinforcing bracket (7), wherein the connecting element (9) is formed of a material different from the material of the inner ring (6) and / or the outer ring (6) and / or the magnetic element (8) and / or the reinforcing pillar (7).

2. The rotor (1) according to claim 1. Its features are, The connecting element (9) is formed of a material with an elastic modulus between 400 MPa and 46000 MPa.

3. The rotor (1) according to claim 1 or 2. Its features are, The connecting element (9) is formed of a material that has elastic behavior during the operation of the rotor (1).

4. The rotor (1) according to any one of the preceding claims. Its features are, The connecting element (9) is rod-shaped and has an average thickness (10) of >0.47 mm, preferably 0.5 mm to 10 mm, and particularly preferably 0.5 mm to 5 mm in the circumferential direction.

5. The rotor (1) according to any one of the preceding claims. Its features are, The connecting element (9) has at least one connecting portion (13) that deviates from the shape of the rod and rests at least partially on one of the magnetic elements (8).

6. The rotor (1) according to any one of the preceding claims. Its features are, The connecting element (9) is basically the same.

7. The rotor (1) according to any one of the preceding claims. Its features are, The reinforcing strut (7) is cubic, wherein each of the connecting elements (9) rests at least partially against the longitudinal surface (11) of one of the reinforcing struts (7).

8. The rotor (1) according to any one of the preceding claims. Its features are, The outer ring (6) is covered with an annular auxiliary bandage (12).

9. A method for producing rotors for axial flux machines (2), particularly rotors for axial flux machines (2) in the transmission system (3) of motor vehicles (4), the method comprising the following steps: - Provide molding tools (14). - Provides multiple reinforcing pillars (7). - Provides multiple magnetic components (8). - The reinforcing struts (7) and the magnetic elements (8) are arranged in the molding tool such that the reinforcing struts (7) are positioned in a spoke manner and the magnetic elements (8) are arranged between each pair of circumferentially adjacent reinforcing struts (7), and wherein, in the molding tool (14), an air gap (15) is provided on both sides of each reinforcing strut (7) between one of the magnetic elements (8) and the corresponding reinforcing support (7). - Use the molding tool (14) to inject and mold the inner ring (5) and outer ring (6), so that the reinforcing post (7), the magnetic element (8), the inner ring (5) and the outer ring (6) are fixed in position relative to each other. - The air gap (15) on both sides of one of the reinforcing pillars (7) is filled with a material different from the material of the inner ring (6) and the outer ring (6) and / or the magnetic element (8) and / or the reinforcing pillar (7), so that a connecting element (9) is formed between one of the magnetic elements (8) and the corresponding reinforcing support (7).

10. A method for producing rotors for axial flux machines (2), particularly rotors for axial flux machines (2) in the transmission system (3) of motor vehicles (4), the method comprising the following steps: - Provide molding tools (14). - Provides multiple reinforcing pillars (7). - Provides multiple magnetic components (8). - Provide multiple connecting elements (9) with materials different from those of the inner ring (6) and / or the outer ring (5) and / or the magnetic element (8) and / or the reinforcing strut (7). - The reinforcing struts (7) and the magnetic elements (8) are arranged in the molding tool such that the reinforcing struts (7) are positioned in a spoke manner and the magnetic elements (8) are arranged between each pair of circumferentially adjacent reinforcing struts (7), and wherein, in the molding tool (14), an air gap (15) is provided on both sides of each reinforcing strut (7) between one of the magnetic elements (8) and the corresponding reinforcing support (7). - Use the molding tool (14) to inject and mold the inner ring (5) and outer ring (6), so that the reinforcing post (7), the magnetic element (8), the inner ring (5) and the outer ring (6) are fixed in position relative to each other. - Insert the connecting element (9) into the air gap (15) on both sides of one of the reinforcing pillars (7).

Images