Rotor and motor

Abstract

The invention relates to a rotor (4) of an electric machine (1), in particular for use in a drive train of a hybrid or all-electric motor vehicle. The rotor (4) has at least one first rotor body (5) with a first group of permanent magnets (6) and a second rotor body (7) with a second group of permanent magnets (8), wherein: the first rotor body (5) and the second rotor body (7) can be rotated relative to each other about a common axis of rotation (10) by means of mechanical field damping means (11) against the action of first torsional stiffness means (9); each rotor body (5, 7) has a two-part design and comprises an inner ring gear (28) connected in a torque-transmitting manner to the rotor shaft (16) and an outer ring gear (29) connected in a torque-transmitting manner to the inner ring gear (28); and the permanent magnets (6, 8) are located only in the outer ring gear (29) made of electrical sheet steel.

Description

Technical Field

[0001] The present invention relates to a rotor for an electric machine, in particular for use in the drivetrain of a hybrid or fully electric motor vehicle, wherein the rotor comprises at least a first rotor body having a first set of permanent magnets and a second rotor body having a second set of permanent magnets, the first rotor body and the second rotor body being rotatable relative to each other about a common rotation axis by means of a mechanical field damping mechanism, overcoming the action of a first torsional stiffness mechanism. The invention also relates to an electric machine. Background Art

[0002] Electric motors are increasingly being used to drive motor vehicles, creating an alternative to fossil fuel-intensive internal combustion engines. Significant efforts have been made to improve the suitability of electric drives for everyday use while also providing users with the driving comfort they are accustomed to.

[0003] Perhaps the closest prior art is a detailed description of electric drives in the article "Highly Integrative and Flexible – Electric Drive Unit for Electric Vehicles" (Hochintegrativ und flexibel – Elektrische Antriebseinheit für E-Fahrzeuge) by Erik Schneider, Frank Fickl, Bernd Cebulski, and Jens Liebold, published in the German automotive magazine ATZ, Volume 113, May 2011, pp. 360-365. This article describes a drive unit for a vehicle axle, which includes an electric motor arranged coaxially with respect to a bevel gear differential. Such a drive unit is also known as an e-axle or an electrically operable drivetrain.

[0004] Electric motors experience losses during operation due to magnetic reversals. These losses are collectively referred to as iron losses and reduce machine efficiency. In mobile applications, low motor efficiency can mean reduced vehicle range or increased demands on battery capacity. Minimizing these iron losses is therefore an ongoing goal, particularly in mobile applications with purely electric drives.

[0005] An example of such an electric machine with iron losses, such as that used in the drivetrains of hybrid or all-electric motor vehicles, is a so-called permanently excited synchronous machine. Due to their high power density compared to other types of machines, permanently excited synchronous machines are preferred for use in electric vehicles, where available installation space is often a limiting factor. The machine's excitation field is typically generated by permanent magnets arranged in the machine's rotor. In permanently excited synchronous machines, the slip ring contacts required in electrically excited synchronous machines to power the field coils arranged on the rotor can be omitted.

[0006] However, a disadvantage of permanent excitation is that the excitation field cannot be easily modified. In principle, a synchronous machine can be operated beyond its rated speed by controlling the so-called field decay range. Within this range, the machine operates at its maximum rated power, with the torque delivered by the machine decreasing as speed increases. Electrically excited synchronous machines can be very easily operated within the field decay range by reducing the excitation current. Even in the case of permanently excited machines, methods are known to generate an air gap field component by supplying a suitable current to the machine's stator, which counteracts the excitation field generated by the permanent magnets and thus weakens it. However, such control of the machine leads to increased losses, so that the machine can only operate at reduced efficiency within this range.

[0007] An effective method for reducing iron losses in electric machines is to intentionally weaken the magnetic field between the stator and rotor for high-speed operating points, because with a weak magnetic field, the losses due to high-frequency magnetic reversals are lower. In addition to electrical methods, there are also mechanical methods for targeted field attenuation. Patent specifications US58211710, FR2831345, EP1085644, EP11867030, DE1012011708670, DE1012016103470, CN104600929 and CN105449969 disclose a rotor for a radial flux machine, which is divided into a plurality of rotor disks perpendicular to the axis of rotation, the rotor disks being equipped with permanent magnets and rotatable relative to each other, the rotor providing a full magnetic field in a position where the magnetic poles are axially aligned, and a weakened magnetic field in a position rotated relative to this position, depending on the relative rotation between the rotor disks. Active or passive mechanisms are described that are said to be able to switch between these two positions depending on the rotor speed or torque, and thus enable the electric machine to operate more efficiently across the entire motor characteristic map.

[0008] DE 10 2021 101 898 describes an arrangement in which the rotor of a radial flux machine is divided into two rotor segments, the individual rotor disks of which alternate axially. One rotor segment is directly connected to the rotor shaft, and the other rotor segment is connected to the rotor shaft via a torsional stiffness mechanism for torque-transmitting rotation. The torsional stiffness mechanism is selected such that, at low torques, the rotor segments are in a rotational position with a weakened magnetic field, and at high torques, the rotor segments are in a torsional position with a full magnetic field. DE 10 12021 101 904 claims protection for a structurally designed mechanical module that can be introduced into the interior of a rotor disk equipped with permanent magnets, produces the described connection of the rotor segments to the rotor shaft, and allows the control characteristic curve to be defined via the torsional stiffness mechanism, which is implemented using a spring and a cam mechanism equipped with rollers.

[0009] All previously mentioned passive solutions that use torque as a sensor variable to overcome the torsional stiffness mechanism to trigger the relative movement between the two rotor segments assume that, in a position where the initial magnetic field with misaligned poles is attenuated, the total electromagnetic torque generated by the stator current supply is simply distributed between the two rotor segments, roughly according to their share of the total length and their respective phase positions relative to the stator field, regardless of the presence of the other rotor segments. Only in this way can a partial torque proportional to the total torque be easily directed to overcome the torsional stiffness mechanism between the rotor segment or one of the rotor segments and the rotor shaft and bring the desired rotation into a position with full magnetic field and aligned poles with increased torque. However, experiments and modeling by the applicant have shown that the actual situation is much more complicated.

[0010] Even in the de-energized state, the rotor disks of the two rotor sections interact in the form of a magnetic repulsive torque. A position with full magnetic field and aligned poles results in an unstable equilibrium in which the repulsive torque disappears. When rotating from this equilibrium position, a repulsive torque is generated that increases with increasing rotation until it reaches a maximum value and then decreases again with further rotation. The trajectory of the repulsive torque over the rotation angle within the electrical cycle, the height of the maximum value, and the rotation angle at which the maximum value occurs depend largely on the type of permanent magnet arrangement chosen within the rotor disks. The trajectory within the electrical cycle is essentially nonlinear.

[0011] Given the desired effective stator current supply for different speeds, these magnetic repulsive torques increase in different ways depending on the speed, sometimes by several times. Overall, the resulting partial torque cannot easily overcome the torsional stiffness between the rotor segment or one of the rotor segments and the rotor shaft in any case, so that the rotor segment is rotated into a position with a full magnetic field, because the partial torque is not directed in the correct direction due to the high proportion of the magnetic repulsive torque.

[0012] Reliable control behavior requires, among other things, that the control characteristic curve of the mechanical field damping on the motor characteristic diagram exhibit neither undesirable changes nor excessive hysteresis. However, at the speeds of modern traction machines in the automotive sector, an undesirably high deviation of the control characteristic curve toward higher torques can be observed due to the influence of centrifugal forces. Increased friction between the components of the mechanical field damping mechanism at high speeds can also lead to excessive hysteresis in the control characteristic curve.

[0013] To provide the required installation space for such mechanical field damping mechanisms between the rotor shaft and the rotor's outer ring, corresponding recesses are typically provided in the rotor's electrical steel sheets. The cavities for the permanent magnets are located within these recesses. However, these recesses reduce the remaining cross-section and thus reduce the rotor disk's speed stability. This can lead to an undesirable reduction in the motor's power density.

[0014] In order to provide a functional arrangement in the sense of the aforementioned passive solutions for torque-adaptive field damping of a rotor of an electric machine, it is an object of the present invention to provide a rotor provided with improved mechanical field damping, in particular at high speeds. Summary of the Invention

[0015] This object is achieved by a rotor of an electric machine, in particular a rotor of an electric machine for use in a drive train of a hybrid or fully electric motor vehicle, wherein the rotor has at least a first rotor body with a first set of permanent magnets and a second rotor body with a second set of permanent magnets, the first rotor body and the second rotor body being rotatable relative to each other around a common rotation axis by means of a mechanical field damping mechanism overcoming the action of a first torsional stiffness mechanism; and the rotor bodies each have a two-part design, comprising an inner ring gear connected to the rotor shaft in a torque-transmitting manner and an outer ring gear coupled to the inner ring gear in a torque-transmitting manner, and the permanent magnets are arranged only in the outer ring gear made of electrical steel sheets.

[0016] This offers the advantage that the electric machine can be implemented with a purely mechanical field damping device which adjusts the position of the permanent magnets in the rotor, as required by the field damping requirements, in a reliable and cost-effective manner, depending on the operating conditions of torque and speed. Thus, in principle, the invention also avoids the need for external actuators on or in the rotor.

[0017] According to the present invention, the rotor body has a two-part design with an inner ring gear and an outer ring gear. The inner ring gear begins radially far enough inward relative to the magnet pockets containing the permanent magnets that it is essentially outside the magnetic flux and does not have to be made of electrical steel sheets. Thus, the inner ring gear can be made, for example, of high-strength (hardened) steel and, in particular, also accommodate and support components for mechanical field damping.

[0018] The connection between the inner ring gear and the outer ring gear can be form-fitting, integral, and / or friction-locked. The inner ring gear is preferably formed from a different material than the rotor laminations. The inner ring gear is also preferably formed from a stronger material than the electrical steel laminations of the outer ring gear.

[0019] In particular, the electric machine can be designed as a rotary machine. In this case, a distinction is made between radial flux machines and axial flux machines. A radial flux machine is characterized by the magnetic field lines extending radially in the air gap formed between the rotor and the stator, while an axial flux machine has magnetic field lines extending axially in the air gap formed between the rotor and the stator. Within the context of the present invention, the electric machine can be configured as a radial flux machine or an axial flux machine.

[0020] The rotor is the rotating part of the electric machine. It comprises, in particular, a rotor shaft and one or more rotor bodies formed from a rotor lamination stack, which are arranged on the rotor shaft in a rotationally fixed manner. The rotor shaft can be hollow, which, on the one hand, reduces weight and, on the other hand, allows lubricant or coolant to be supplied to the rotor bodies.

[0021] For the purposes of the present invention, the rotor body is understood to mean the rotor without the rotor shaft. The rotor body therefore comprises, in particular, the rotor lamination stack and the permanent magnets inserted into the recesses of the rotor lamination stack or fixed to the circumference of the rotor lamination stack, as well as any axial covering parts for closing the recesses.

[0022] The permanent magnets can preferably be inserted into pockets of the rotor lamination stack. Each pocket can be provided with a single larger rotor magnet designed as a bar magnet or a plurality of smaller permanent magnet elements.

[0023] The rotor has a plurality of rotor bodies. Particularly preferably, the rotor bodies are formed substantially identically, in particular in a substantially identical manner. It is highly preferred that the rotor bodies be formed from identical, in particular substantially identical, rotor laminations. Therefore, the rotor body is particularly preferably formed from a rotor lamination stack, which consists of a plurality of laminated individual sheets or rotor laminations, typically made of electrical steel, which are layered and stacked one on top of the other to form a stack, referred to as a rotor lamination stack. The individual laminations can be held together in the rotor lamination stack by adhesive bonding, welding, screwing, or riveting. In particular, the rotor lamination stack can also include permanent magnets, which are inserted into recesses in the rotor lamination stack or are circumferentially fixed to the rotor lamination stack.

[0024] Mechanical field attenuation mechanisms are generally known from the prior art. Particularly preferred mechanical field attenuation mechanisms in the context of the present invention are described in the as yet unpublished patent publications DE 10 20 22 10 69 44 and DE 10 20 22 10 69 45 as well as DE 10 20 21 10 19 04 B3, DE 10 20 21 10 18 98 A1 and DE 10 20 21 10 19 00 A1, which are hereby incorporated by reference into the disclosure of the present application.

[0025] According to an advantageous embodiment of the present invention, the inner ring gear can be made of steel, in particular hardened steel. The advantage of this design is that the use of steel can contribute to higher speed load capacity of the rotor and a longer service life of the motor. (Hardened) steel can also better withstand high temperatures and mechanical loads, which can further improve the reliability and service life of the motor. The high heat resistance of steel also helps to improve the thermal load capacity of the rotor and thus allows the rotor to be used in applications with high temperatures.

[0026] According to a further preferred embodiment of the present invention, the inner ring gear and the outer ring gear can also be connected to each other in a torque-transmitting manner with a positive fit. This allows for a connection method that is generally more stable, wear-resistant, and vibration-resistant than other connection methods, which increases the reliability and service life of the rotor. A positive connection can also offer advantages in terms of assembly, as it is generally easier to produce than, for example, welding two ring gears together. It is particularly preferred that the positive connection has no play in the circumferential direction in order to avoid impact-type mechanical loads caused by play during operation of the rotor.

[0027] Furthermore, according to an equally advantageous embodiment of the invention, the inner ring gear can also have an external tooth system on its outer side, which engages in a corresponding internal tooth system on the inner side of the outer ring gear. The technical advantage of an inner ring gear of the rotor of an electric machine that has an external tooth system on its outer side, which engages in a corresponding internal tooth system on the inner side of the outer ring gear, is a particularly high connection stiffness and torque transmission efficiency. Advantages related to the thermal loadability of the rotor can also be achieved, as the tooth system improves heat dissipation and thus increases the thermal loadability of the rotor.

[0028] According to another particularly preferred embodiment of the present invention, the external and internal tooth systems can also be designed as plug-in tooth systems. This makes assembly and disassembly of the ring gear particularly easy. The plug-in tooth system allows the two ring gears to be simply plugged together and disconnected without having to loosen or tighten the connection. This makes maintenance and servicing of the rotor much easier, allowing this work to be performed more quickly and efficiently. If the rotor body is damaged or defective, the plug-in tooth system also makes it faster and easier to replace the rotor body.

[0029] Furthermore, the present invention can be further developed such that each of the multiple teeth of the external tooth system has a first undercut, and each of the multiple teeth of the internal tooth system has a second undercut, wherein the first undercut and the second undercut are designed to enable radial force transmission between the meshing internal and external tooth systems. Thus, this type of tooth system with undercuts not only allows torque to be transmitted from the electrical steel laminations of the outer ring gear to the inner ring gear, but also absorbs radial centrifugal forces acting on the electrical laminations of the outer ring gear at high speeds.

[0030] In a likewise preferred embodiment of the invention, the teeth of the external toothing system and / or the teeth of the internal toothing system can also be dovetail-shaped in cross section, which has proven to be particularly advantageous for the transmission of circumferential and radial forces.

[0031] It can also be advantageous if the invention is further developed so that the external tooth system has a groove with a groove base between two circumferentially adjacent teeth, in which groove the teeth of the internal tooth system engage with tooth heads with clearance relative to the groove base. This ensures, among other things, that the two ring gears only contact one another on the inclined flanks of the teeth, which are designed, for example, in the form of a dovetail. The high precision of the tooth shape for the form-fitting connection is therefore limited by the inclined flanks. In addition, the radial clearance can be used to heat the inner ring gear to a certain degree before assembly, so that when the outer ring gear is assembled, the teeth have clearance all around, and the desired gap-free contact, for example, on the inclined flanks of the dovetail teeth, is only achieved when the teeth have cooled. If a corresponding overlap is provided between the inclined flanks of the dovetail teeth of the external tooth system and the internal tooth system, this also makes it possible to preload the outer ring gear radially inwards during assembly.

[0032] According to another preferred embodiment of the subject matter of the invention, the external tooth system and / or the internal tooth system can have chamfers. This simplifies the connection or axial insertion of the ring gears into one another.

[0033] Finally, the invention can also advantageously be designed such that the permanent magnets are arranged in pairs distributed in a V-shaped manner in cross section on the circumference of the outer ring gear, the free legs of the V-shaped arrangement extending radially inwards and the V-shaped arrangement having a radially extending mirror axis that runs coaxially with respect to the radially extending mirror axis of the teeth of the internal or external toothing system, and / or the permanent magnets are arranged in pairs distributed in a V-shaped manner in cross section on the circumference of the outer ring gear, the free legs of the V-shaped arrangement extending radially inwards and defining a radially extending mirror axis between two circumferentially adjacent V-shaped arrangements that runs coaxially with respect to the radially extending mirror axis of the teeth of the internal or external toothing system. It has been shown that such an arrangement of the toothing system relative to the permanent magnets can contribute to a particularly advantageous and high torsional strength of the connection between the inner and outer ring gears.

[0034] The object of the invention is also achieved by an electric machine comprising a stator and a rotor spaced apart from the stator by an air gap, the rotor being designed as a rotor according to one of claims 1 to 10 .

[0035] The object of the present invention is also achieved by a kit of parts for producing a mechanical field damping device for a rotor of an electric machine, in particular for use in the drive train of a hybrid or fully electric motor vehicle, comprising:

[0036] a first rotor body having a first receiving recess and a second rotor body, the first rotor body and the second rotor body being rotatable relative to each other about a common rotation axis against the action of a first torsional stiffness mechanism,

[0037] a first torsional stiffness mechanism designed as a first torsional spring arrangement with a first torsional spring, which can be positioned coaxially with respect to the axis of rotation and between the first rotor body and the second rotor body or between one of the rotor bodies and the rotor shaft, such that a rotation of one of the rotor bodies, which begins during adjustment of the field damping mechanism, can cause an opening or closing actuation of the first torsional spring, and the first torsional spring has at least one first spring leg,

[0038] a first receiving shoe in which the first spring leg can be positioned and which in turn can be received in a first receiving pocket of the first rotor body and fixed to the first rotor body, so that the first spring leg of the first torsion spring can be coupled to the first rotor body without play in the axial direction and in the circumferential direction relative to the first rotor body.

[0039] One advantage of this kit is that it provides a simple and flexible solution for manufacturing and assembling mechanical field attenuation mechanisms. By using pre-constructed and pre-assembled parts, installation and maintenance can be performed more easily and quickly. The kit is also more flexible and adaptable to different applications and motor vehicle types. The kit can also reduce costs by simplifying the supply chain and reducing inventory levels. For example, the kit can be a packaging unit. In addition, the kit can be designed as a combination of separate storage containers for storing the individual components of the kit or corresponding groups of components. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] The invention is explained in more detail below with reference to the accompanying drawings without limiting the general idea of ​​the invention.

[0041] In the attached figure:

[0042] Figure 1 The motor is shown in cross-section;

[0043] Figure 2 A schematic circuit block diagram of a rotor with a mechanical field damping mechanism is shown;

[0044] Figure 3 The rotor is shown in cross-section;

[0045] Figure 4 A detailed view of the rotor is shown in cross-sectional representation;

[0046] Figure 5 A first embodiment of a torsion spring arrangement with two rotor bodies is shown in exploded perspective representation;

[0047] Figure 6shows a perspective view of a first embodiment of a torsion spring arrangement with two rotor bodies in an assembled state;

[0048] Figure 7 shows a detailed enlarged view of the rotor body having a torsion spring arrangement thereon;

[0049] Figure 8 The kit of parts is shown in a schematic representation. DETAILED DESCRIPTION

[0050] Figure 1 An electric machine 1 is shown, in particular for use in the drive train of a hybrid or fully electric motor vehicle. The electric machine 1, which is designed as a radial flux machine, comprises a stator 2 and a rotor 4 separated from the stator 2 by an air gap 3, wherein the rotor 4 has at least a first rotor body 5 with a first set of permanent magnets 6 and a second rotor body 7 with a second set of permanent magnets 8, which can be seen by observing Figure 1 and Figure 2 Easy to understand.

[0051] The first rotor body 5 and the second rotor body 7 can rotate relative to each other around a common rotation axis 10 by means of a mechanical field damping mechanism 11, overcoming the action of the first torsional stiffness mechanism 9. The two rotor bodies 5, 7 are essentially formed from the same rotor laminations, and the position and number of the first set of permanent magnets 6 in the rotor body 5 are the same as the position and number of the second set of permanent magnets 8 in the rotor body 7.

[0052] Figure 2 The field damping mechanism 11, shown by way of example in FIG, comprises an unspecified lever element that is pivotable about a pivot point, wherein the first rotor body 5 can be coupled to a first lever portion of the lever element, and the second rotor body 7 can be coupled to a second lever portion of the lever element. The first and second lever portions are arranged on opposite sides of the lever, so that the first and second rotor bodies 5, 7 can be rotated relative to each other by tilting the lever element to achieve the desired adjustment of the mechanical field damping mechanism 11. The field damping mechanism 11 is described in detail in DE 10 20 22 10 69 44 and DE 10 20 22 10 69 45, so reference is made here to avoid repetition.

[0053] like Figure 1 As already indicated in , the rotor bodies 5, 7 each have a two-part design, comprising an inner ring gear 28 connected to the rotor shaft 16 in a torque-transmitting manner and an outer ring gear 29 coupled in a torque-transmitting manner to the inner ring gear 28, the permanent magnets 6, 8 being arranged only in the outer ring gear 29 made of electrical steel sheet. The inner ring gear 28 is made of steel, in particular hardened steel.

[0054] Figure 3An embodiment is shown in which an inner ring gear 28 and an outer ring gear 29 are connected to each other in a torque-transmitting, form-fitting manner. To this end, the inner ring gear 28 has an external tooth system 51 on its outer side surface 50, which engages in a corresponding internal tooth system 52 on the inner side surface 53 of the outer ring gear 29. In this exemplary embodiment, the outer tooth system 51 and the inner tooth system 52 are designed as plug-in tooth systems. To facilitate the connection of this plug-in tooth system, the outer tooth system 51 and / or the inner tooth system 52 can have chamfers.

[0055] from Figure 4 As can be seen in the detailed illustration, the teeth 54 of the external tooth system 51 each have a first undercut 55, and the teeth 56 of the internal tooth system 52 also have a second undercut 57. The first and second undercuts 55, 57 are designed to enable radial force transmission between the meshing internal and external tooth systems 52, 51. To achieve this, the teeth 54 of the external tooth system 51 and the teeth 56 of the internal tooth system 52 have a dovetail-shaped cross-section. In this case, the two ring gears 28, 29 contact only the inclined flanks of the dovetail-shaped teeth 54, 56. Therefore, the high precision of the tooth shape for the form-fit connection is limited by the inclined flanks. This also allows for the use of larger radii in the tooth bases of the ring gears 28, 29. This reduces local stresses and enables faster and more cost-effective production of the tooth systems 51, 52, for example, by selecting a milling cutter with a larger diameter. The undercuts 55, 57 are thus generated by the inclined flanks of the teeth 54, 56. In this form, the opening of the tooth gaps in the ring gears 28 , 29 is wider, which makes it easier and more cost-effective to manufacture the tooth system, for example by broaching, forming or milling.

[0056] The external tooth system 51 also has a groove 58 with a groove base 59 between two circumferentially adjacent teeth 54, into which the teeth 56 of the internal tooth system 52 engage with tooth heads 60 with clearance relative to the groove base 59, which can be seen from the Figure 4 With this design, an overlap can be provided, in particular, in the tooth flanks of the meshing teeth 54, 56, which results in an inward prestressing of the inner ring gear 28 and the outer ring gear 29 during assembly and thus further reduces the stress of the ring gears 28, 29 at rotational speed.

[0057] The permanent magnets 6, 8 are arranged in pairs distributed in a V-shaped manner in cross section on the circumference of the outer ring gear 29, the free legs 61 of the V-shaped arrangement extending radially inwards, and the V-shaped arrangement having a radially extending mirror axis 62, which extends coaxially with respect to the radially extending mirror axis 63 of the teeth 54, 56 of the internal tooth system 52 or the external tooth system 51. At the same time, a radially extending mirror axis 64 is defined between two circumferentially adjacent V-shaped arrangements and extends coaxially with respect to the radially extending mirror axis 65 of the teeth 56 of the internal tooth system 52 or the external tooth system 51. In this case, Figure 4 It is also clearly shown that the toothing 54 of the external toothing system 51, through which the mirror axes 62, 63 extend, is wider in the circumferential direction than the circumferentially adjacent teeth 54 of the external toothing system 51. The same applies to the toothing 56 of the internal toothing system 52, through which the mirror axes 64, 65 extend. This means that the effects of the high centrifugal forces caused by the V-shaped arrangement of the permanent magnets 6, 8 in these areas can be better absorbed.

[0058] The first rotor body 5 and the second rotor body 7 can be rotated relative to each other about a common rotation axis 10 by means of a mechanical field damping mechanism 11, overcoming the effect of the first torsional stiffness mechanism 9. Figure 5 More detailed description. Figure 5 As can be seen in FIG, the first torsional stiffness mechanism 9 is designed as a first torsion spring arrangement 12 having a first torsion spring 13, which is arranged coaxially with respect to the rotation axis 10 and between the first rotor body 5 and the second rotor body 7, so that a rotation of one of the rotor bodies 5, 7, which begins during adjustment of the field damping mechanism 11, causes an opening or closing actuation of the first torsion spring 13. Although not shown in the figures, the first torsion spring 13 can also be arranged in a torque-transmitting manner between one of the rotor bodies 5, 7 and the rotor shaft 16.

[0059] The first torsion spring arrangement 12 has a second torsion spring 14 which is arranged coaxially with respect to the rotation axis 10 of the rotor 4 and between the first rotor body 5 and the second rotor body 7 such that a rotation of one of the rotor bodies 5, 7 which begins during adjustment of the field damping mechanism 11 causes an opening or closing actuation of the second torsion spring 14. Figure 5 and Figure 7 As shown in the figure, the first torsion spring 13 and the second torsion spring 14 are designed to be essentially identical and are arranged to be rotated relative to each other about the rotation axis 10 so that the first spring leg 17 and the second spring leg 18 of the first torsion spring 13 are directed to be offset radially outward by 90° in the circumferential direction, and the first spring leg 19 and the second spring leg 20 of the second torsion spring 14 are also directed to be offset radially outward by 90° in the circumferential direction.

[0060] The first torsion spring 13 has a first spring leg 17 extending radially into the first rotor body 5 and a second spring leg 18 extending radially into the second rotor body 7. Similarly, the second torsion spring 14 also has a first spring leg 19 extending radially into the first rotor body 5 and a second spring leg 20 extending radially into the second rotor body 7.

[0061] The first spring leg 17 of the first torsion spring 13 is held in the first receiving shoe 30, which is in turn received in the first receiving pocket 31 of the first rotor body 5 and fixed to the first rotor body 5, so that the first spring leg 17 of the first torsion spring 13 is coupled to the first rotor body without clearance in the axial direction and in the circumferential direction relative to the first rotor body 5. The first receiving shoe 30 can be inserted into the first receiving pocket 31 with clearance.

[0062] from Figure 5 It can also be seen that the first receiving shoe 30 has a first receiving groove 32 , in which the first spring leg 17 of the first torsion spring 13 is arranged without play, for example by means of a press fit.

[0063] The first spring leg 17 of the first torsion spring 13 protrudes from the first receiving groove 32, and the portion 33 protruding from the first receiving groove 32 is supported against the wall 34 of the first receiving recess 31, which can also be seen by observing Figure 7 This allows part of the shoe load to be absorbed by the rotor body 5. The wall 34 of the first receiving pocket 31 has a convex profile that projects into the first receiving pocket 31, and this can also be seen from Figure 7 This ensures, for example, that the position of the spring leg 17 can also be adjusted in the direction of rotation.

[0064] Figure 5 It is also shown that the first receiving shoe 30 has a first opening 35 through which a first fastening means 36 passes, by means of which the first receiving shoe 30 is fixed to the first rotor body 5 .

[0065] Figure 5 It is also shown that the second spring leg 18 of the first torsion spring 13 is retained in the second receiving shoe 37, which in turn is received in the second receiving pocket 38 of the second rotor body 7 and fixed to the first rotor body 7, so that the second spring leg 18 of the first torsion spring 13 is coupled to the second rotor body 7 without gap in the axial direction and in the circumferential direction relative to the second rotor body 7.

[0066] The first spring leg 19 of the second torsion spring 14 is also held in a similar manner in the third receiving shoe 39, which in turn is received in the third receiving recess of the first rotor body 5 and fixed to the first rotor body 5, so that the first spring leg 19 of the second torsion spring 14 is coupled to the first rotor body 5 without gap in the axial direction and in the circumferential direction relative to the first rotor body 5.

[0067] Finally, the second spring leg 20 of the second torsion spring 14 is also held in the fourth receiving shoe 41, which is in turn received in the fourth receiving recess 42 of the second rotor body 7 and fixed to the second rotor body 7, so that the second spring leg 20 of the second torsion spring 14 is coupled to the second rotor body without gap in the axial direction and in the circumferential direction relative to the second rotor body 7.

[0068] Figure 5 It is also shown that the first receiving shoe 30 , the second receiving shoe 37 , the third receiving shoe 39 and the fourth receiving shoe 41 are formed identically.

[0069] By means of the receiving shoes 30, 37, 39, 41, an element is thus arranged between the spring legs 17, 18, 19, 20 and the rotor body 5, which is adjustable and fixable in terms of its position within the receiving recesses 31, 38, 42. The receiving shoes 30, 37, 39, 41 are pressed onto the spring legs 17, 18, 19, 20, for example by corresponding oversizing, so that they are fixed to each other without play. The spring legs 17, 18, 19, 20 with the preassembled receiving shoes 30, 37, 39, 41 can be positioned in the rotor body 5, 7 using an assembly tool (not shown). Since a gap is formed between the receiving recesses 31, 38, 42 and the receiving shoes 30, 37, 39, 41, that is, the receiving shoes 30, 37, 39, 41 are engaged with a gap in the receiving recesses 31, 38, 42, the position of the receiving shoes 30, 37, 39, 41 in the receiving recesses 31, 38, 42 can be adjusted. The receiving shoes 30, 37, 39, 41 positioned in the receiving recesses 31, 38, 42 can then be fixed by the fastening device 36. The fastening device is shown as a screw in the figure. However, the fastening device can also be designed as a rivet or the fastening device 36 can be a brazed connection or a welded connection.

[0070] Figure 6 Shown in assembled state Figure 5 The known arrangement structure.

[0071] Figure 8 A kit 43 of parts for producing a mechanical field damping device 11 for a rotor 4 of an electric machine 1, in particular for use in a drive train of a hybrid or fully electric motor vehicle, is shown, comprising:

[0072] A first rotor body 5 having a first receiving pocket 31 and a second rotor body 7 , the first rotor body 5 and the second rotor body 7 being rotatable relative to each other around a common rotation axis 10 against the action of a first torsional stiffness means 9 .

[0073] a first torsional stiffness mechanism 9 designed as a first torsional spring arrangement 12 with a first torsional spring 13, which can be positioned coaxially with respect to the axis of rotation 10 and between the first rotor body 5 and the second rotor body 7 or between one of the rotor bodies 5, 7 and the rotor shaft 16, so that a rotation of one of the rotor bodies 5, 7, which begins during adjustment of the field damping mechanism 11, can lead to an opening or closing actuation of the first torsional spring 13, and the first torsional spring 13 has at least one first spring leg 17,

[0074] a first receiving shoe 30 in which the first spring leg 17 can be positioned and which in turn can be received in a first receiving pocket 31 of the first rotor body 5 and fixed to the first rotor body 5, so that the first spring leg 17 of the first torsion spring 13 can be coupled to the first rotor body without play in the axial direction and in the circumferential direction relative to the first rotor body 5.

[0075] As shown, the kit 43 can provide receiving shoes 30 , 37 , 39 , 41 for all spring legs 17 , 18 , 19 , 20 of the torsion spring arrangement 12 , and the receiving shoes 30 , 37 , 39 , 41 can be designed essentially identically.

[0076] The present invention is not limited to the embodiments shown in the accompanying drawings. Therefore, the above description should not be regarded as restrictive, but rather as illustrative. The appended claims should be understood to mean that the recited features are present in at least one embodiment of the present invention. This does not exclude the presence of other features. Where the claims and the above description specify a "first" feature and a "second" feature, such designation is used to distinguish between two features of the same type and does not define an order of precedence.

[0077] Reference Signs List

[0078] 1 motor

[0079] 2 stator

[0080] 3 Air gap

[0081] 4 rotors

[0082] 5. Rotor body

[0083] 6 permanent magnets

[0084] 7 Rotor body

[0085] 8 permanent magnets

[0086] 9 Torsional stiffness mechanism

[0087] 10 Axis of rotation

[0088] 11 Field attenuation mechanism

[0089] 12 Torsion spring arrangement

[0090] 13 Torsion spring

[0091] 14 Torsion spring

[0092] 16 rotor shaft

[0093] 17 Spring Leg

[0094] 18 Spring Legs

[0095] 19 Spring Leg

[0096] 20 Spring Legs

[0097] 28 Ring gear

[0098] 29 Ring gear

[0099] 30 Acceptance Hoof

[0100] 31 Receiving pocket

[0101] 32 receiving grooves

[0102] 33 parts

[0103] 34 wall

[0104] 35 Opening

[0105] 36 Fastening devices

[0106] 37 Acceptance Hoof

[0107] 38 receiving pockets

[0108] 39 Acceptance Hoof

[0109] 41 Acceptance Hoof

[0110] 42 receiving pockets

[0111] 43 complete sets of parts

[0112] 50 lateral surface

[0113] 51 External tooth system

[0114] 52 Internal tooth system

[0115] 53 lateral surface

[0116] 54 teeth

[0117] 55 undercut

[0118] 56 teeth

[0119] 57 Undercut

[0120] 58 grooves

[0121] 59 groove base

[0122] 60 tooth head

[0123] 61 Legs

[0124] 62 Mirror Axis

[0125] 63 Mirror Axis

[0126] 64 Mirror Axis

[0127] 65 Mirror Axis

Claims

1. A rotor (4) of an electric machine (1), in particular for use in a drive train of a hybrid or fully electric motor vehicle, wherein: The rotor (4) comprises at least a first rotor body (5) with a first set of permanent magnets (6) and a second rotor body (7) with a second set of permanent magnets (8), wherein the first rotor body (5) and the second rotor body (7) are rotatable relative to each other about a common rotation axis (10) by means of a mechanical field damping mechanism (11) against the action of a first torsional stiffness mechanism (9), It is characterized by: The rotor bodies (5, 7) each have a two-part design, comprising an inner ring gear (28) connected to the rotor shaft (16) in a torque-transmitting manner and an outer ring gear (29) coupled to the inner ring gear (28) in a torque-transmitting manner, wherein the permanent magnets (6, 8) are arranged only in the outer ring gear (29) formed from electrical steel sheets.

2. The rotor (4) according to claim 1, It is characterized by: The inner ring gear (28) is made of steel, in particular hardened steel.

3. The rotor (4) according to claim 1 or 2, It is characterized by: The inner ring gear (28) and the outer ring gear (29) are connected to each other in a torque-transmitting manner in a form-fitting manner.

4. The rotor (4) according to claim 3, It is characterized by: The inner ring gear (28) has an external tooth system (51) on its outer side surface (50), which engages in a corresponding internal tooth system (52) on the inner side surface (53) of the outer ring gear (29).

5. The rotor (4) according to claim 4, It is characterized by: The external tooth system (51) and the internal tooth system (52) are designed as plug-in tooth systems.

6. The rotor (4) according to claim 4 or 5, It is characterized by: The plurality of teeth (54) of the external tooth system (51) each have a first undercut (55), and the plurality of teeth (56) of the internal tooth system (52) each have a second undercut (57), wherein the first undercut (55) and the second undercut (57) are designed to enable force to be transmitted radially between the meshing internal tooth system (52) and the external tooth system (51).

7. The rotor (4) according to claim 6, It is characterized by: The plurality of teeth (54) of the external tooth system (51) and / or the plurality of teeth (56) of the internal tooth system (52) have a dovetail-shaped cross section.

8. The rotor (4) according to claim 6 or 7, It is characterized by: The external tooth system (51) has, between two circumferentially adjacent teeth (54), a groove (58) with a groove base (59), into which the teeth (56) of the internal tooth system (52) engage with tooth heads (60), wherein the tooth heads (60) have clearance relative to the groove base (59).

9. The rotor (4) according to any one of claims 4 to 8, It is characterized by: The external tooth system (51) and / or the internal tooth system (52) have chamfers.

10. A rotor (4) according to any one of claims 4 to 9, It is characterized by: The permanent magnets (6, 8) are arranged in pairs distributed in a V-shaped manner in cross section on the circumference of the outer ring gear (29), wherein the free legs (61) of the V-shaped arrangement extend radially inwards and the V-shaped arrangement has a radially extending mirror axis (62) which extends coaxially with respect to a radially extending mirror axis (63) of the teeth (54, 56) of the internal tooth system (52) or the external tooth system (51), and / or The permanent magnets (6, 8) are arranged in pairs distributed in a V-shaped manner in cross section on the circumference of the outer ring gear (29), wherein the free legs (61) of the V-shaped arrangement structure extend radially inward and a radially extending mirror axis (64) is defined between two circumferentially adjacent V-shaped arrangements, and the mirror axis extends coaxially with respect to a radially extending mirror axis (65) of the teeth (56) of the internal tooth system (52) or the external tooth system (51).

11. An electric machine (1) comprising a stator (2) and a rotor (4) spaced apart from the stator (2) by an air gap (3), It is characterized by: The rotor (4) is designed as a rotor according to any of the preceding claims.

12. A kit (43) for producing a mechanical field damping device (11) for a rotor (4) of an electric machine (1), in particular for use in a drive train of a hybrid or fully electric motor vehicle, comprising: a first rotor body (5) having a first receiving recess (31) and a second rotor body (7), wherein the first rotor body (5) and the second rotor body (7) are rotatable relative to each other about a common rotation axis (10) against the action of a first torsional stiffness means (9), a first torsional stiffness mechanism (9) designed as a first torsional spring arrangement (12) with a first torsional spring (13), the first torsional spring being positionable coaxially with respect to the rotation axis (10) and being positioned between the first rotor body (5) and the second rotor body (7) or between one of the rotor bodies (5, 7) and a rotor shaft (16), such that a rotation of one of the rotor bodies (5, 7) starting when the field damping mechanism (11) is adjusted can result in an opening or closing actuation of the first torsional spring (13), and the first torsional spring (13) having at least one first spring leg (17), a first receiving shoe (30) in which the first spring leg (17) can be positioned, and which in turn can be received in a first receiving recess (31) of the first rotor body (5) and fixed to the first rotor body (5), so that the first spring leg (17) of the first torsion spring (13) can be coupled to the first rotor body (5) without clearance in the axial direction and in the circumferential direction relative to the first rotor body.

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