Electric machine, method for producing mechanical magnetic field attenuation mechanism, mechanical magnetic field attenuation mechanism, and kit of parts

Abstract

The invention relates to an electric machine (1), in particular for use in a powertrain of a hybrid drive motor vehicle or an all-electric drive motor vehicle, comprising a stator (2) and a rotor (4) spaced apart from the stator (2) by an air gap (3), 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). 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) against the influence of the first rotational stiffness element (9) by means of a mechanical field damping mechanism (11), and at least one first spring leg (17) of the first leg spring (13) is held in a first receiving block (30), the first receiving block is received in a first receiving recess (31) of the first rotor body (5) and is fixed to the first rotor body (5) such that a first spring leg (17) of the first leg spring (13) is coupled to the first rotor body (5) in an axial direction and a circumferential direction in a play-free manner with respect to the first rotor body (5).

Description

Technical Field

[0001] The present invention relates to an electric machine, in particular for use in the powertrain of a hybrid or fully electric motor vehicle, comprising a stator and a rotor separated from the stator by an air gap, wherein the rotor comprises 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, wherein the first rotor body and the second rotor body are rotatable relative to each other about a common rotation axis by means of a mechanical field damping mechanism, overcoming the influence of a first torsional stiffness element. The invention also relates to a method for producing the mechanical field damping mechanism, the mechanical field damping mechanism, and a kit of parts. Background Art

[0002] Electric motors are increasingly being used to power 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] A detailed description of electric drives can be found in the article by Erik Schneider, Frank Fickl, Bernd Cebulski, and Jens Liebold in the German automotive magazine ATZ, Volume 113, May 2011, pages 360-365. The article is titled "Highly integrated and flexible electric drive unit for electric vehicles." This article, which is perhaps the closest prior art, describes a drive unit for a vehicle axle that includes 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 operable powertrain.

[0004] Electric motors experience losses during operation due to magnetic reversals. These losses are collectively referred to as iron losses and reduce the efficiency of the machine. In mobile applications, low motor efficiency means reduced vehicle range or increased demand for battery capacity. Minimizing these iron losses is therefore a constant goal, especially in mobile applications with purely electric drives.

[0005] An example of an electric machine with iron losses, such as that used in the powertrain of hybrid or all-electric vehicles, is a permanently excited synchronous machine. Due to their higher 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, by controlling the field decay range, a synchronous machine can be operated beyond its rated speed. 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 easily operated within the field decay range by reducing the excitation current. Even in the case of permanently excited machines, there are known methods for generating an air gap field component by supplying a suitable current to the machine's stator. This counteracts the excitation field generated by the permanent magnets and thus weakens the excitation field. However, such control of the machine results in increased losses, forcing the machine to 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 operating points with high speeds, 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 US Pat. No. 58211710, FR2831345, EP1085644, EP11867030, DE1012011708670, DE1012016103470, CN104600929, and CN105449969 disclose a rotor for a radial flux machine, which is divided into several rotor disks equipped with permanent magnets perpendicular to the axis of rotation and which can rotate relative to each other. Depending on the relative rotation between the rotor disks, the rotor provides a full magnetic field in a position where the magnetic poles are aligned in the axial direction, and a weakened magnetic field in a position rotated relative to this position. An active or passive mechanism is described which is said to be able to switch between these two positions depending on rotor speed or torque and which thus enables the electric machine to operate more efficiently with respect to the entire engine map.

[0008] DE 10 12021 101 898 describes a device in which the rotor of a radial flux machine is divided into two partial rotors, the individual rotor disks of which alternate in the axial direction. One rotor part is directly connected to the rotor shaft, the other part is connected to the rotor shaft in a torque-transmitting manner via a torsional stiffening element. The torsional stiffening element is selected so that: at low torques, the partial rotor is in a torsional position with a weakened magnetic field, and at high torques, the partial rotor is 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, establishes the described connection of the partial rotors to the rotor shaft, and allows the definition of an adjustment characteristic curve via the torsional stiffening element, which is implemented using a spring and a cam drive equipped with rollers.

[0009] All of the aforementioned passive solutions—which use torque as a sensor variable to overcome the torsional stiffness to trigger the relative movement between the two rotor segments—assume that, in the initial field-depleted position with misaligned poles, 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 the partial torques, which are proportional to the total torque, be easily directed to overcome the torsional stiffness between the rotor segment or one of the rotor segments and the rotor shaft, and achieve the desired rotation by means of the increased torque into a position with full magnetic field and aligned poles. However, experiments and modeling by the applicant have shown that the actual situation is much more complex.

[0010] Even in the de-energized state, there is an interaction between the rotor disks of the two sub-rotors in the form of a magnetic repulsive torque. The position with full magnetic field and aligned poles represents 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 curve of the repulsive torque as a function of 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 selected within the rotor disks. The curve 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 is not easily oriented to overcome the torsional stiffness between the partial rotor or one of the partial rotors and the rotor shaft, and thus cannot rotate the partial rotor into a position with a full magnetic field, because the partial torque is not directed in the right direction for this purpose due to the high proportion of the magnetic repulsive torque.

[0012] For reliable control behavior, it is necessary, among other things, that the control characteristic curve of the mechanical field damping on the engine map neither shifts undesirably nor exhibits excessive hysteresis. However, at the speeds of traction machines in today's automotive industry, the influence of centrifugal forces, in particular on existing torsional stiffness elements, which can be designed as compression springs, leads to an undesirably high shift of the control characteristic curve toward higher torques. Increased friction on the guide elements of the torsional stiffness elements can also lead to excessive hysteresis in the control characteristic curve. Summary of the Invention

[0013] In order to provide a functional device in the sense of the aforementioned passive solution for torque-adaptive field damping of a rotor of an electric machine, the present invention aims to provide an electric machine with improved mechanical field damping. It is also aimed to provide an optimized method for producing a field damping mechanism and an improved mechanical field damping mechanism. It is also aimed to provide a kit of parts for producing a mechanical field damping mechanism for a rotor of an electric machine.

[0014] This object is achieved by an electric machine, in particular for use in a powertrain of a hybrid or fully electric motor vehicle, comprising a stator and a rotor separated from the stator by an air gap, wherein the rotor comprises 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, wherein the first rotor body and the second rotor body are rotatable relative to each other about a common rotation axis by means of a mechanical field damping mechanism, against the influence of a first torsional stiffness element, wherein the first torsional stiffness element is designed as a first leg spring arrangement with a first leg spring, the first leg spring Arranged coaxially with 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 initiated when the field damping mechanism is adjusted causes the first leg spring to open or close, wherein at least one first spring leg of the first leg spring is held in a first receiving block which in turn is received in a first receiving recess of the first rotor body and is fixed to the first rotor body, such that the first spring leg of the first leg spring is coupled to the first rotor body in an axial direction as well as in a circumferential direction in a play-free manner relative to the first rotor body.

[0015] 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 required for field damping as required, depending on the operating conditions of torque and speed, in a reliable and cost-effective manner. Thus, in principle, the invention also avoids the need for actuators intervening externally on or in the rotor.

[0016] Designing the torsionally rigid element as a leg spring device for defining the control characteristic for damping the magnetic field by relative rotation of the rotor body in particular allows reducing the influence of centrifugal forces on the control characteristic and its hysteresis.

[0017] The play-free arrangement of the spring legs in the receiving blocks allows very precise positioning of the spring legs in the corresponding receiving pockets, which also contributes to a play-free arrangement of the spring legs relative to the rotor body and to corresponding tolerance compensation between the connected components.

[0018] This connection also makes it possible to adjust the center of gravity of the leg springs precisely to the axis of rotation of the rotor, which is particularly important with regard to unbalance at high rotor speeds exceeding 15,000 rpm.

[0019] The receiving block is preferably designed such that it can transmit both torque and force, which can come from a counterforce of a leg spring, for example.

[0020] It is also preferred that the contact points between the spring leg and the spring block and, if applicable, the wall of the receiving pocket are at different radii, which means that forces can be introduced into the leg spring without lateral forces. This can contribute, among other things, to a particularly secure and safe clamping of the spring leg.

[0021] In particular, the electric machine can be designed as a rotating machine. In the case of an electric machine designed as a rotating machine, a distinction is made between radial flux machines and axial flux machines. A radial flux machine is characterized by the magnetic field lines extending in the radial direction in the air gap formed between the rotor and the stator, while in the case of an axial flux machine, the magnetic field lines extend in the axial direction in the air gap formed between the rotor and the stator. In the context of the present invention, the electric machine can be configured as a radial flux machine or an axial flux machine.

[0022] The rotor is the rotating (rotating) part of the electric machine. Specifically, it comprises a rotor shaft and one or more rotor bodies formed by a stack of rotor laminations arranged non-rotatably on the rotor shaft. The rotor shaft can be hollow, which reduces weight and allows lubricant or coolant to be supplied to the rotor body.

[0023] For the purposes of the present invention, a rotor body is understood to mean a rotor without a rotor shaft. The rotor body is therefore made in particular of the rotor lamination stack and the permanent magnets inserted into the pockets 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 pockets.

[0024] 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.

[0025] A plurality of rotor bodies are provided. Particularly preferably, the rotor bodies are formed from substantially identical parts, in particular substantially identical parts. Highly preferably, the rotor bodies are formed from identical rotor laminations, in particular substantially identical rotor laminations. Therefore, the rotor body is particularly preferably formed from a rotor lamination stack, which is composed of a plurality of laminated individual sheets or rotor laminations, typically made of electrical steel, which are layered and stacked one above the other to form a stack, i.e., a rotor lamination stack. The individual laminations can be held together in the rotor lamination stack by gluing, welding, or screwing. The rotor lamination stack can also, in particular, include permanent magnets, which are inserted into recesses in the rotor lamination stack or are circumferentially fixed to the rotor lamination stack.

[0026] Mechanical field damping mechanisms are generally known from the prior art. Particularly preferred mechanical field damping mechanisms relevant to the present invention are described in the unpublished DE 102022106944 and DE 102022106945, as well as in the patent publications DE 102021101904 B3, DE 102021101898 A1, and DE 102021101900 A1, which are hereby incorporated by reference into the disclosure of the present application.

[0027] According to a preferred embodiment of the invention, the first leg spring arrangement can include a second leg spring, which is arranged coaxially with the rotor's axis of rotation and between the first and second rotor bodies or between one of the rotor bodies and the rotor shaft, such that when the field damping mechanism is adjusted, a rotation of one of the rotor bodies causes the second leg spring to open or close. This design has the advantage that the second leg spring enables modeling and precise adjustment of the adjustment characteristic curve. The leg springs can have essentially the same or different designs, depending on the requirements of the specific application to be achieved by the desired adjustment characteristic curve. The leg springs can be connected in series or in parallel with one another.

[0028] According to another preferred embodiment of the present invention, the first leg spring may include a first spring leg extending radially into the first rotor body and / or a second spring leg extending radially into the second rotor body, and / or the first leg spring may include a first spring leg extending axially into the first rotor body and / or a second spring leg extending axially into the second rotor body, and / or the second leg spring may include a first spring leg extending radially into the first rotor body and / or a second spring leg extending radially into the second rotor body, and / or the second leg spring may include a first spring leg extending axially into the first rotor body and / or a second spring leg extending axially into the second rotor body. This allows for a particularly compact radial or axial torsional stiffening element to be realized, depending on the given installation space.

[0029] Furthermore, according to an equally advantageous embodiment of the present invention, the first and second leg springs can be designed as essentially identical parts and arranged approximately 180° relative to one another about the axis of rotation, such that the first and second spring legs of the first leg spring point in a common radial and / or axial direction, and the first and second spring legs of the second leg spring are oriented in radial and / or axial directions opposite to those of the first leg spring. This advantageously prevents or at least mitigates lateral forces generated when the leg springs are actuated and design imbalances in the rotating rotor. For example, a set of two identical opening and closing leg springs can be formed, wherein the corresponding distance between the coils allows the first and second leg springs to be screwed into one another and then rotated 180° relative to one another. Preferably, the distance between the coils of the leg springs is slightly greater than the wire thickness of the leg springs in the axial direction.

[0030] In an equally preferred embodiment of the invention, it can also be provided that at least one leg spring, preferably all leg springs, are wound from a spring wire having a substantially rectangular cross-section. This increases the energy content of the leg spring in its installation space and facilitates the bending torque transmission and lateral, forceless suspension of the spring ends designed as legs in the recess of the disk, which forms a structural unit with a rotor part or the rotor shaft for transmitting torque.

[0031] It may also be advantageous to further develop the invention so that at least one leg spring, preferably all leg springs, are preloaded. This has the advantage that the torque at which the adjustment process should begin can be defined. To this end, the leg springs in the device can then be installed preloaded, for example, about a specific rotation angle.

[0032] According to an advantageous embodiment of the invention, it can be provided that the first receiving block can be inserted into the first receiving recess with some play. This design has the advantage that the position of the first spring leg of the first leg spring can be slightly varied and thus adjusted without impairing the coupling between the first spring leg and the first rotor body.

[0033] According to a further preferred embodiment of the present invention, the first receiving block may include a first receiving recess, in which the first spring leg of the first leg spring is arranged without play. This allows for precise setting of the adjustment characteristic curve of the leg spring arrangement. A further advantage is that this reduces friction between the components and thus increases the service life of the leg spring arrangement.

[0034] Furthermore, according to an equally advantageous embodiment of the invention, it can be provided that the first spring leg of the first leg spring protrudes from the first receiving recess, wherein the section protruding from the first receiving recess rests against the wall of the first receiving cavity. This design has the advantageous effect that some of the mechanical loads can be absorbed by the corresponding rotor body during operation of the rotor.

[0035] According to another particularly preferred embodiment of the invention, it can be provided that the wall of the first receiving recess has a convex contour that projects into the first receiving recess. This has the particular effect that the positioning of the spring leg relative to the receiving recess can be widely adjusted.

[0036] Furthermore, the present invention can be further developed such that the first receiving block has a first opening through which the first fastening device penetrates, and the first receiving block is fixed to the first rotor body by means of the first fastening device. This design has the advantage that the gap between the receiving block and the receiving recess can be adjusted particularly easily.

[0037] In a likewise preferred embodiment of the invention, it can also be provided that the first leg spring arrangement has a second leg spring which is arranged coaxially with the axis of rotation of the rotor and is arranged between the first rotor body and the second rotor body or between one of the rotor bodies and the rotor shaft.

[0038] Characterized in that a rotation of one of the rotor bodies, which begins when the field damping mechanism is adjusted, causes the second leg spring to open or close, and the first leg spring and the second leg spring are designed as essentially identical components and are arranged rotated about 180° relative to each other about the axis of rotation, so that the first spring leg and the second spring leg of the first leg spring are pointed in a common radial direction and / or axial direction, and the first spring leg and the second spring leg of the second leg spring are oriented in a radial direction and / or axial direction opposite to the first spring leg and the second spring leg of the first leg spring.

[0039] The present invention can also advantageously be further developed such that the second spring leg of the first leg spring is retained in a second receiving block, which is in turn received in a second receiving recess of the second rotor body and fixed to the first rotor body, such that the second spring leg of the first leg spring is coupled to the second rotor body in an axial and circumferential direction with respect to the second rotor body in a play-free manner; and / or the first spring leg of the second leg spring is retained in a third receiving block, which is in turn received in a third receiving recess of the first rotor body and fixed to the first rotor body, such that the first spring leg of the second leg spring is coupled to the first rotor body in an play-free manner in an axial and circumferential direction with respect to the first rotor body; and / or the second spring leg of the second leg spring is retained in a fourth receiving block, which is in turn received in a fourth receiving recess of the second rotor body and fixed to the second rotor body, such that the second spring leg of the second leg spring is coupled to the second rotor body in an play-free manner in an axial and circumferential direction with respect to the second rotor body. This has the advantage that the adjustability of the adjustment characteristic curve can be correspondingly improved.

[0040] According to another preferred embodiment of the object of the present invention, it can be provided that the first receiving block, the second receiving block, the third receiving block and the fourth receiving block are designed identically. This makes it possible to reduce the production costs of the receiving blocks due to the high degree of uniformity.

[0041] Furthermore, the object of the present invention is achieved by a method for producing a mechanical field attenuation mechanism, the method comprising the following steps:

[0042] providing a first rotor body and a second rotor body, the first rotor body having a first receiving recess,

[0043] providing a first torsionally rigid element, which is designed as a first leg spring arrangement with a first leg spring having a first spring leg and a second spring leg,

[0044] Set up the first receiving block,

[0045] Fixing the first receiving block to the first spring leg in a play-free manner,

[0046] Insert the first receiving block into the first receiving recess with some play, and

[0047] fixing the receiving block to the first rotor body so that the first spring leg of the first leg spring is coupled to the first rotor body in an axial direction and in a circumferential direction in a play-free manner relative to the first rotor body,

[0048] coupling the second spring leg to the second rotor body or rotor shaft,

[0049] The first and second rotor bodies are rotatable relative to each other about a common rotation axis, overcoming the influence of the first torsional stiffness member, so that rotation of one of the rotor bodies initiated when adjusting the field damping mechanism may cause the first leg spring to open or close.

[0050] The object of the present invention is further achieved by a mechanical field damping mechanism for a rotor of an electric machine, in particular for use in a powertrain of a hybrid or fully electric motor vehicle, wherein the rotor comprises at least a first rotor body and a second rotor body, wherein the first rotor body and the second rotor body are rotatable relative to each other about a common rotation axis against the influence of a first torsional stiffness element, wherein the first torsional stiffness element is designed as a first leg spring arrangement having a first leg spring, which is arranged coaxially with the rotation axis and between the first and second rotor bodies or between one of the rotor bodies and the rotor shaft, such that a rotation of one of the rotor bodies, initiated when the field damping mechanism is adjusted, causes the first leg spring to open or close, wherein at least one first spring leg of the first leg spring is held in a first receiving block, which in turn is received in a first receiving recess of the first rotor body and is fixed to the first rotor body, such that the first spring leg of the first leg spring is coupled to the first rotor body in an axial direction and in a circumferential direction without play relative to the first rotor body.

[0051] Furthermore, the object of the present invention is achieved by a kit of parts for producing a mechanical field damping mechanism for a rotor of an electric machine, in particular for use in a powertrain of a hybrid or fully electric motor vehicle, comprising:

[0052] a first rotor body and a second rotor body, the first rotor body having a first receiving recess, wherein the first rotor body and the second rotor body are rotatable relative to each other about a common rotation axis against the influence of the first torsional stiffness element,

[0053] a first torsionally rigid element designed as a first leg spring arrangement with a first leg spring, which can be positioned coaxially with 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, initiated when adjusting the field damping mechanism, can lead to an opening or closing of the first leg spring, and the first leg spring having at least one first spring leg,

[0054] a first receiving block in which the first spring leg can be positioned and which in turn can be received in a first receiving recess of the first rotor body and can be fixed to the first rotor body, so that the first spring leg of the first leg spring can be coupled to the first rotor body in an axial direction as well as in a circumferential direction in a play-free manner relative to the first rotor body.

[0055] One advantage of this parts kit is that it provides a simple and flexible solution for the production and assembly of mechanical field attenuation mechanisms. By using pre-assembled and pre-assembled components, installation and maintenance can be performed more quickly and easily. The parts kit is also more flexible and adaptable to different applications and vehicle types. It can also reduce costs by streamlining the supply chain and reducing inventory levels. For example, the parts kit can be a packaging unit. Furthermore, the parts kit can be designed as a combination of separate storage containers for the individual components of the parts kit or corresponding component groups. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] The invention is explained in more detail below with reference to the accompanying drawings without limiting the general concept of the invention.

[0057] In the attached figure:

[0058] Figure 1 The electric machine is shown in cross section,

[0059] Figure 2 shows a schematic block diagram of a rotor with a mechanical field damping mechanism,

[0060] Figure 3 The leg spring device and two rotor bodies of the first embodiment are shown in an exploded perspective view.

[0061] Figure 4 shows a perspective view of the leg spring device and two rotor bodies of the first embodiment in an assembled state,

[0062] Figure 5 shows a perspective view of a rotor body to which the leg spring arrangement of the first embodiment is fixed,

[0063] Figure 6 shows a cross-sectional view of a rotor body with the leg spring arrangement of the first embodiment fixed to the rotor body,

[0064] Figure 7 shows an enlarged detailed view of a section of a rotor body to which the leg spring arrangement of the first embodiment is fixed,

[0065] Figure 8shows an axial cross-section of a rotor body to which the leg spring arrangement of the first embodiment is fixed,

[0066] Figure 9 shows a perspective view of a first embodiment of a leg spring arrangement,

[0067] Figure 10 Three embodiments of receiving blocks for spring legs are shown in each case in a perspective view,

[0068] Figure 11 A perspective view showing a fourth embodiment of the receiving block and the leg spring arrangement,

[0069] Figure 12 shows a perspective view of the rotor body with the leg spring arrangement fixed to the rotor body,

[0070] Figure 13 shows a perspective view of a rotor body with another embodiment of a leg spring device fixed to the rotor body,

[0071] Figure 14 A kit of parts for producing a mechanical field damping mechanism for use in a rotor of an electric motor is shown.

[0072] Figure 15 The rotor is shown in cross-section,

[0073] Figure 16 A detailed view of the rotor is shown in a cross-sectional view. DETAILED DESCRIPTION

[0074] Figure 1 An electric machine 1 is shown, in particular for use in a powertrain of a hybrid or fully electric motor vehicle. The electric machine 1 is constructed as a radial flux machine and 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 one 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 together. Figure 1 and Figure 2 Easy to understand.

[0075] 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 influence of the first torsional stiffness element 9. The two rotor bodies 5, 7 are essentially formed from the same rotor laminations, wherein the position and number of the first set of permanent magnets 6 in the rotor body 5 are identical to the position and number of the second set of permanent magnets 8 in the rotor body 7.

[0076] Figure 2The field damping mechanism 11, shown by way of example in FIG, comprises a rod element (not specified in further detail) that can be pivoted about a pivot point, wherein the first rotor body 5 can be coupled to a first rod section, and the second rotor body 7 can be coupled to a second rod section of the rod element. The first and second rod sections are arranged on opposite sides of the rod, so that by tilting the rod element, the first rotor body 5 and the second rotor body 7 can be rotated relative to each other for 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.

[0077] As from Figure 3 As can be seen in the figure, the first torsionally rigid element 9 is designed as a first leg spring device 12 having a first leg spring 13, which is arranged coaxially with 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 when the field damping mechanism 11 is adjusted, results in an opening or closing of the first leg spring 13. Even if not shown in the figure, the first leg spring 13 can also be arranged in a torque-transmitting manner between one of the rotor bodies 5, 7 and the rotor shaft 16.

[0078] The first leg spring arrangement 12 has a second leg spring 14 which is arranged coaxially with the axis of rotation 10 of the rotor 4 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 when the field damping mechanism 11 is adjusted, results in the second leg spring 14 opening or closing. Figure 3 As shown in the figure, the first leg spring 13 and the second leg spring 14 are designed essentially identically and are arranged rotated approximately 180° 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 leg spring 13 are directed radially outwardly offset by 90° in the circumferential direction, and the first spring leg 19 and the second spring leg 20 of the second leg spring 14 are also directed radially outwardly offset by 90° in the circumferential direction.

[0079] The first leg 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 leg 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.

[0080] The first spring leg 17 of the first leg spring 13 is held in the first receiving block 30, which is in turn received in the 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 leg spring 13 is coupled to the first rotor body 5 in the axial direction and the circumferential direction in a clearance-free manner relative to the first rotor body. The first receiving block 30 can be inserted into the first receiving recess 31 with clearance, which is Figure 7 It can also be clearly seen in the figure that the gap between the receiving block 41 and the receiving recess 42 is clearly visible.

[0081] Figure 3 It is also shown that the first receiving block 30 has a first receiving groove 32 , in which the first spring leg 17 of the first leg spring 13 is arranged in a play-free manner, for example by means of a press fit. Figure 10 Various embodiments of the receiving groove 32 are shown.

[0082] The first spring leg 17 of the first leg spring 13 protrudes from the first receiving groove 32, wherein the section 33 protruding from the first receiving groove 32 rests against the wall 34 of the first receiving pocket 31. This allows a portion of the block load to be absorbed by the rotor body 5. The wall 34 of the first receiving pocket 31 has a convex profile that protrudes into the first receiving pocket 31, which can also be seen from the Figure 7 This ensures, for example, that the position of the spring leg 17 can also be adjusted in the direction of rotation.

[0083] Figure 3 It is also shown that the first receiving block 30 has a first opening 35 through which a first fastening device 36 passes, by means of which the first receiving block 30 is fixed to the first rotor body 5 .

[0084] Figure 3 It is also shown that the second spring leg 18 of the first leg spring 13 is held in a second receiving block 37, which in turn is received in a second receiving recess 38 of the second rotor body 7 and is fixed to the first rotor body 7, so that the second spring leg 18 of the first leg spring 13 is coupled to the second rotor body 7 in an axial direction and in a circumferential direction in a clearance-free manner relative to the second rotor body.

[0085] In a similar manner, the first spring leg 19 of the second leg spring 14 is also held in the third receiving block 39, which in turn is received in the third receiving recess 40 of the first rotor body 5 and fixed to the first rotor body 5, so that the first spring leg 19 of the second leg spring 14 is coupled to the first rotor body 5 in an axial direction and in a circumferential direction in a clearance-free manner relative to the first rotor body.

[0086] Finally, the second spring leg 20 of the second leg spring 14 is also held in the fourth receiving block 41, which in turn is 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 leg spring 14 is coupled to the second rotor body 7 in an axial direction and in a circumferential direction in a clearance-free manner relative to the second rotor body.

[0087] Figure 3 It is also shown that the first receiving block 30 , the second receiving block 37 , the third receiving block 39 and the fourth receiving block 41 are designed identically.

[0088] Therefore, an element that can be adjusted and fixed in place in a receiving recess 31, 38, 40, 42 by means of a receiving block 30, 37, 39, 41 is arranged between the spring legs 17, 18, 19, 20 and the rotor body 5. The receiving block 30, 37, 39, 41 is pressed onto the spring legs 17, 18, 19, 20, for example, by a corresponding oversize, so that the receiving block and the spring legs are fixed to each other in a play-free manner. The spring legs 17, 18, 19, 20 with the preassembled receiving block 30, 37, 39, 41 can be positioned in the rotor body 5, 7 using an assembly tool (not shown). Because a gap is formed between the receiving recesses 31, 38, 42 and the receiving blocks 30, 37, 39, 41, i.e., the receiving blocks 30, 37, 39, 41 engage with play in the receiving recesses 31, 38, 42, the position of the receiving blocks 30, 37, 39, 41 in the receiving recesses 31, 38, 42 can be adjusted. The receiving blocks 30, 37, 39, 41 positioned in the receiving recesses 31, 38, 42 can then be fixed in place by the fastening means 36. The fastening means are shown as screws in the figures. However, the fastening means can also be designed as rivets, or the fastening means 36 can be provided in the form of brazed or welded connections.

[0089] Figure 4 Shown from Figure 3 The mechanical field damping mechanism 11 can be produced or assembled, for example, as follows. First, a first rotor body 5 and a second rotor body 7 are provided, along with a first torsional stiffness element 9. The first rotor body has a first receiving recess 31. The first torsional stiffness element is designed as a first leg spring device 12 having a first leg spring 13 with a first spring leg 17 and a second spring leg 18. Furthermore, a first receiving block 30 is provided.

[0090] The first receiving block 30 is then fixed to the first spring leg 17 in a play-free manner, for example, by means of a press fit. The first receiving block 30, with the first spring leg 17 fixed therein, is then inserted, with play, into the first receiving recess 31. In this assembled position, the receiving block 30 is then fixed to the first rotor body 5, so that the first spring leg 17 of the first leg spring 13 is coupled to the first rotor body 5 in a play-free manner in the axial direction and in the circumferential direction relative to the first rotor body. To complete the assembly of the first torsional stiffness element 9, the second spring leg 18 is then coupled to the second rotor body 7 or the rotor shaft 16.

[0091] Therefore, the first rotor body 5 and the second rotor body 7 can rotate relative to each other around the common rotation axis 10 overcoming the influence of the first torsional stiffness member 9, so that the rotation of one of the rotor bodies 5, 7 starting when the field damping mechanism 11 is adjusted can cause the first leg spring 13 to open or close.

[0092] Figures 5 to 8 Various views of the leg spring arrangement 12 on the first rotor body 5 are shown in a partially assembled state.

[0093] Figure 9 The leg spring arrangement 12 is shown in an exposed perspective view. Among other things, it can be easily seen that the leg springs 13, 14 are formed from a spring wire having a substantially rectangular cross section, wherein the short edges of the leg springs 13, 14 of rectangular cross section extend in the axial direction and the long edges are oriented in the circumferential direction.

[0094] Figure 3 Three different embodiments of the receiving block 30 are shown. In the upper variant, designated a, the receiving groove 32 is open radially inwards and in the circumferential direction, but is closed radially outwards, so that the spring leg 17 accommodated in the receiving groove 32 can also be arranged in the receiving groove 32 in a play-free manner radially outwards. In principle, it is also conceivable to design the receiving groove 32 in the form of a channel, so that the spring leg 17 can be inserted into the receiving groove 32 from radially inwards to radially outwards and fixed in the receiving groove in a play-free manner. Figure 10 In addition, the receiving groove 32 can also be opened in the radial direction, the circumferential direction and the axial direction, as shown in FIG. Figure 10 As seen in image c.

[0095] Figure 11 A further embodiment of a receiving block 30 is shown, which is shaped like a ring segment and has an opening 35 at each of its circumferential ends for receiving a fastening device 36 .

[0096] Figure 12A further embodiment of a leg spring arrangement 12 is shown, in which the spring leg 20 is axially preloaded by a spring element 44 .

[0097] Figure 15 and Figure 16 An embodiment is shown in which an inner annular disk 28 and an outer annular disk 29 are connected to one another in a torque-transmitting manner. For this purpose, the inner annular disk 28 has an external toothing 51 on its outer circumferential surface 50, which engages in a corresponding internal toothing 52 on the inner circumferential surface 53 of the outer annular disk 29. In this exemplary embodiment, the outer toothing 51 and the inner toothing 52 are designed as splice-type toothings. To facilitate this splice-type toothing connection, the outer toothing 51 and / or the inner toothing 52 may have chamfers.

[0098] from Figure 16 As can be seen in the detailed illustration in FIG, each tooth 54 of the outer toothing 51 has a first undercut 55, and each tooth 56 of the inner toothing 52 has a second undercut 57. The first and second undercuts 55, 57 are designed to enable force transmission in the radial direction between the meshing inner and outer toothings 52, 51. To achieve this, the teeth 54 of the outer toothing 51 and the teeth 56 of the inner toothing 52 have a dovetail-shaped cross-section. Here, the two annular disks 28, 29 contact only on 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 to the inclined flanks. This also allows for the use of larger radii in the tooth bases of the annular disks 28, 29. This reduces local stresses and enables faster and more cost-effective production of the toothings 51, 52, for example, by selecting a milling tool with a larger diameter. The undercuts 55, 57 are thus generated by the inclined flanks of the teeth 54, 56. In this form, the openings of the tooth gaps in the annular disks 28 , 29 are wider, which makes it easier and more cost-effective to produce the toothing, for example by broaching, forming or milling.

[0099] The outer toothing 51 further comprises a groove 58 having a groove base 59 between two teeth 54 adjacent in the circumferential direction, into which the teeth 56 of the inner toothing 52 engage with tooth tips 60, wherein the tooth tips 60 have play relative to the groove base 59, which can be seen from the Figure 4 In this design, an overlap can be provided in particular in the tooth flanks of the meshing teeth 54, 56, which results in an inward preload of the inner and outer annular disks 28, 29 during assembly and thus further reduces the stresses in the annular disks 28, 29 at speed.

[0100] The permanent magnets 6 and 8 are arranged in pairs in a V-form in cross section and distributed on the circumference of the outer annular disk 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 the radially extending mirror axis 63 of the teeth 54 and 56 of the inner toothing 52 or the outer toothing 51. At the same time, a radially extending mirror axis 64 is defined between two adjacent V-shaped arrangements in the circumferential direction, which extends coaxially with the radially extending mirror axis 65 of the teeth 56 of the inner toothing 52 or the outer toothing 51. In this case, Figure 4 It is also clearly shown that the meshing teeth 54, 56 through which the mirror axes 62, 63 extend are wider in the circumferential direction than the adjacent teeth 54, 56. The same applies to the meshing teeth 54, 56 through which the mirror axes 64, 65 extend.

[0101] Figure 14 A kit of parts 43 is shown for producing a mechanical field damping device 11 for a rotor 4 of an electric machine 1 , in particular for use in a powertrain of a hybrid or fully electric motor vehicle, comprising:

[0102] a first rotor body 5 and a second rotor body 7 , the first rotor body having a first receiving recess 31 , wherein the first rotor body 5 and the second rotor body 7 can rotate relative to each other around a common rotation axis 10 against the influence of the first torsional stiffness element 9 ,

[0103] a first torsionally rigid element 9 designed as a first leg spring arrangement 12 with a first leg spring 13, which can be positioned coaxially with 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 when the field damping mechanism 11 is adjusted, can lead to an opening or closing of the first leg spring 13, and the first leg spring 13 has at least one first spring leg 17,

[0104] a first receiving block 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 can be fixed to the first rotor body 5, so that the first spring leg 17 of the first leg spring 13 can be connected to the first rotor body 5 in an axial direction as well as in a circumferential direction in a manner free of play relative to the first rotor body.

[0105] As shown, the parts kit 43 can provide receiving blocks 30 , 37 , 39 , 41 for all spring legs 17 , 18 , 19 , 20 of the leg spring device 12 , wherein the receiving blocks 30 , 37 , 39 , 41 are designed essentially identically.

[0106] 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 define 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.

[0107] Reference Signs List

[0108] 1 motor

[0109] 2 stator

[0110] 3 Air gap

[0111] 4 rotors

[0112] 5. Rotor body

[0113] 6 permanent magnets

[0114] 7 Rotor body

[0115] 8 permanent magnets

[0116] 9 Torsional stiffness element

[0117] 10 Axis of rotation

[0118] 11 Field attenuation mechanism

[0119] 12 Leg spring device

[0120] 13 Leg spring

[0121] 14 Leg spring

[0122] 16 Rotor shaft

[0123] 17 Spring Leg

[0124] 18 Spring Legs

[0125] 19 Spring Leg

[0126] 20 Spring Legs

[0127] 28 annular disk

[0128] 29 annular disk

[0129] 30 Acceptance Block

[0130] 31 Receiving pocket

[0131] 32 receiving grooves

[0132] 33 sections

[0133] 34 wall

[0134] 35 Opening

[0135] 36 Fastening device

[0136] 37 Acceptance Block

[0137] 38 receiving pockets

[0138] 39 Acceptance Block

[0139] 40 receiving pocket

[0140] 41 Acceptance Block

[0141] 42 receiving pockets

[0142] 43 parts kit

[0143] 44 Spring element

[0144] 50 lateral surface

[0145] 51 external teeth

[0146] 52 internal teeth

[0147] 53 lateral surface

[0148] 54 teeth

[0149] 55 undercut

[0150] 56 teeth

[0151] 57 Undercut

[0152] 58 grooves

[0153] 59 groove base

[0154] 60 tooth tip

[0155] 61 Legs

[0156] 62 Mirror Axis

[0157] 63 Mirror Axis

[0158] 64 Mirror Axis

[0159] 65 Mirror Axis

Claims

1. An electric machine (1), in particular for use in a powertrain of a hybrid or fully electric motor vehicle, comprising a stator (2) and a rotor (4) separated from the stator (2) by an air gap (3), wherein: The rotor (4) comprises at least one 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 influence of a first torsional stiffness element (9), It is characterized by: The first torsional stiffness element (9) is designed as a first leg spring device (12) having a first leg spring (13), which is arranged coaxially with the rotation axis (10) and is arranged 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) starting when the field damping mechanism (11) is adjusted causes the first leg spring (13) to open or close, wherein at least one first spring leg (17) of the first leg spring (13) is held in a first receiving block (30), which in turn is received in a first receiving recess (31) of the first rotor body (5) and fixed to the first rotor body (5), such that the first spring leg (17) of the first leg spring (13) is coupled to the first rotor body (5) in an axial direction and in a circumferential direction in a clearance-free manner relative to the first rotor body.

2. The electric machine (1) according to claim 1, It is characterized by: The first receiving block (30) can be inserted into the first receiving recess (31) with play.

3. The electric machine (1) according to claim 1 or 2, It is characterized by: The first receiving block (30) has a first receiving groove (32), in which the first spring leg (17) of the first leg spring (13) is arranged in a play-free manner.

4. The electric machine (1) according to claim 3, It is characterized by: The first spring leg (17) of the first leg spring (13) protrudes from the first receiving groove (32), wherein the section (33) protruding from the first receiving groove (32) rests against a wall (34) of the first receiving pocket (31).

5. The electric machine (1) according to claim 4, It is characterized by: The wall (34) of the first receiving recess (31) has a convex profile that protrudes into the first receiving recess (31).

6. An electric machine (1) according to any one of the preceding claims, It is characterized by: The first receiving block (30) has a first opening (35) through which a first fastening device (36) passes, and the first receiving block (30) is fixed to the first rotor body (5) by means of the first fastening device.

7. An electric machine (1) according to any one of the preceding claims, It is characterized by: The first leg spring device (12) has a second leg spring (14), which is arranged coaxially with the rotation axis (10) of the rotor (4) and is arranged 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), The invention relates to a method for adjusting the field damping mechanism (11) and a method for adjusting the field damping mechanism (11). The invention relates to a method for adjusting the field damping mechanism (11) and a method for adjusting the field damping mechanism (11). The invention relates to a method for adjusting the field damping mechanism (11) and a method for adjusting the field damping mechanism (11). The invention relates to a method for adjusting the field damping mechanism (11) and a method for adjusting the field damping mechanism (11). The invention relates to a method for adjusting the field damping mechanism (11) and a method for adjusting the field damping mechanism (11). The invention relates to a method for adjusting the field damping mechanism (11) and a method for adjusting the field damping mechanism (11).

8. The electric machine (1) according to claim 7, It is characterized by: The second spring leg (18) of the first leg spring (13) is held in a second receiving block (37), which in turn is received in a second receiving recess (38) of the second rotor body (7) and is fixed to the first rotor body (7), so that the second spring leg (18) of the first leg spring (13) is coupled to the second rotor body (7) in an axial direction and in a circumferential direction in a play-free manner relative to the second rotor body, and / or The first spring leg (19) of the second leg spring (14) is held in a third receiving block (39), which in turn is received in a third receiving recess (40) of the first rotor body (5) and fixed to the first rotor body (5), so that the first spring leg (19) of the second leg spring (14) is coupled to the first rotor body (5) in an axial direction and in a circumferential direction in a play-free manner relative to the first rotor body, and / or The second spring leg (20) of the second leg spring (14) is held in a fourth receiving block (41), which in turn is received in a 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 leg spring (14) is coupled to the second rotor body (7) in an axial direction and in a circumferential direction in a clearance-free manner relative to the second rotor body.

9. The electric machine (1) according to claim 8, It is characterized by: The first receiving block (30), the second receiving block (37), the third receiving block (39) and the fourth receiving block (41) are designed identically.

10. A method for producing a mechanical field attenuation mechanism (11), the method comprising the following steps: A first rotor body (5) and a second rotor body (7) are provided, wherein the first rotor body has a first receiving recess (31), a first torsionally rigid element (9) is provided, the first torsionally rigid element being designed as a first leg spring device (12) with a first leg spring (13), the first leg spring having a first spring leg (17) and a second spring leg (18), · Setting the first receiving block (30), fixing the first receiving block (30) to the first spring leg (17) in a play-free manner, Inserting the first receiving block (30) into the first receiving recess (31) with play, and fixing the receiving block (30) to the first rotor body (5) so that the first spring leg (17) of the first leg spring (13) is coupled to the first rotor body (5) in an axial direction and in a circumferential direction in a play-free manner relative to the first rotor body, coupling the second spring leg (18) to the second rotor body (7) or rotor shaft (16), enabling the first rotor body (5) and the second rotor body (7) to rotate relative to each other about a common rotation axis (10) against the influence of the first torsional stiffness member (9), such that rotation of one of the rotor bodies (5, 7) initiated when the field damping mechanism (11) is adjusted can cause the first leg spring (13) to open or close.

11. A mechanical field damping device (11) for a rotor (4) of an electric machine (1), in particular for use in a powertrain of a hybrid or fully electric motor vehicle, wherein: The rotor (4) has at least a first rotor body (5) and a second rotor body (7), wherein the first rotor body (5) and the second rotor body (7) are rotatable relative to each other around a common rotation axis (10) against the influence of a first torsional stiffness member (9), It is characterized by: The first torsional stiffness element (9) is designed as a first leg spring device (12) having a first leg spring (13), which is arranged coaxially with the rotation axis (10) and is arranged 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) starting when the field damping mechanism (11) is adjusted causes the first leg spring (13) to open or close, wherein at least one first spring leg (17) of the first leg spring (13) is held in a first receiving block (30), which in turn is received in a first receiving recess (31) of the first rotor body (5) and fixed to the first rotor body (5), such that the first spring leg (17) of the first leg spring (13) is coupled to the first rotor body (5) in an axial direction and in a circumferential direction in a clearance-free manner relative to the first rotor body.

12. A kit of parts (43) for producing a mechanical field damping mechanism (11) for a rotor (4) of an electric machine (1), in particular for use in a powertrain of a hybrid or fully electric motor vehicle, the kit of parts comprising: a first rotor body (5) and a second rotor body (7), the first rotor body having a first receiving recess (31), wherein the first rotor body (5) and the second rotor body (7) are rotatable relative to each other around a common rotation axis (10) against the influence of a first torsional stiffness member (9), a first torsionally rigid element (9) designed as a first leg spring device (12) having a first leg spring (13), the first leg spring being positionable coaxially with the axis of rotation (10), the first leg spring being positioned 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), such that a rotation of one of the rotor bodies (5, 7) initiated when the field damping mechanism (11) is adjusted can result in the first leg spring (13) opening or closing, and the first leg spring (13) having at least one first spring leg (17), a first receiving block (30) in which the first spring leg (17) can be positioned, and which in turn can be received in the first receiving recess (31) of the first rotor body (5) and can be fixed to the first rotor body (5), so that the first spring leg (17) of the first leg spring (13) can be coupled to the first rotor body (5) in an axial direction and in a circumferential direction in a play-free manner relative to the first rotor body.

Images