Rotor, electric machine and kit of parts

Abstract

The invention relates to a rotor (4) for an electric machine (1), in particular for use within a drive train of a hybrid-electric or fully electric motor vehicle, wherein: the rotor (4) comprises at least a first rotor body (5) having a first group of permanent magnets (6), and a second rotor body (7) having a second group of permanent magnets (8); the first rotor body (5) and the second rotor body (7) can be rotated relative to one another about a common axis of rotation (10), against the effect of a first torsional stiffness mechanism (9), by means of a mechanical field-attenuation mechanism (11); the field-attenuation mechanism (11) has a first mechanical stop (12) which limits the rotation of the two rotor bodies (5, 7) relative to one another in a first circumferential direction, and a second mechanical stop (13) which limits the rotation of the two rotor bodies (5, 7) relative to one another in a second circumferential direction; the field-attenuation mechanism (11) has a hub (16) which is coupled to a rotor shaft (14) of the rotor (4) for conjoint rotation; the first rotor body (5) is coupled to a first annular stop disc (17), and the second rotor body (7) is coupled to a second annular stop disc (15); and both the first stop disc (17) and the second stop disc (15) are positioned at an end of the first rotor body (5) that points out of the rotor (4).

Description

[0001] Rotor, electric machine and kit-of-parts

[0002] The present invention relates to a rotor for an electric machine, in particular for use within a drive train of a hybrid or fully electric motor vehicle, wherein the rotor has at least a first rotor body with a first group of permanent magnets and a second rotor body with a second group of permanent magnets, wherein the first rotor body and the second rotor body are rotatable relative to one another against the effect of a first torsional stiffness about a common axis of rotation by means of a mechanical field weakening mechanism, wherein the field weakening mechanism has a first mechanical stop which limits the rotation of the two rotor bodies relative to one another in a first circumferential direction and has a second mechanical stop which limits the rotation of the two rotor bodies relative to one another in a second circumferential direction.The invention further relates to an electrical machine and a kit of parts.

[0003] Electric motors are increasingly being used to power motor vehicles, creating alternatives to combustion engines that require fossil fuels. Considerable efforts have already been made to improve the everyday suitability of electric drives and also to provide users with the same level of driving comfort they are accustomed to.

[0004] A detailed description of an electric drive can be found in an article in the magazine ATZ 113th year, 05 / 2011, pages 360-365 by Erik Schneider, Frank Fickl, Bernd Cebulski and Jens Liebold with the title: Highly integrated and flexible electric drive unit for electric vehicles, which arguably represents the closest state of the art. This article describes a drive unit for one axle of a vehicle which includes an electric motor arranged coaxially with a bevel gear differential. Such drive units are also referred to as e-axles or electrically operated drive trains. During operation, electric machines are subject to losses due to magnetization reversal, which are summarized as iron losses and reduce the machine efficiency. In mobile applications, a low efficiency of the electric machine means a reduced range of the vehicle and increased demand for battery capacity.It is therefore a constant goal, especially in mobile applications with purely electric drive, to minimize the iron losses described.

[0005] An example of such an electrical machine with iron losses, which can be used within the drivetrain of a hybrid or fully electric motor vehicle, is the so-called permanent-magnet synchronous machine. Due to its high power density compared to other machine types, it is particularly popular in the field of electromobility, where the available installation space is often a limiting factor. The machine's excitation field is usually generated by permanent magnets arranged in the machine's rotor. Slip ring contact, which is necessary in electrically excited synchronous machines to supply current to an excitation coil arranged on the rotor, can be dispensed with in the permanent-magnet synchronous machine.

[0006] A disadvantage of permanent magnet excitation, however, 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 weakening range. In this range, the machine operates at its maximum rated power, with the torque output by the machine reducing as the speed increases. Electrically excited synchronous machines can be operated very easily in the field weakening range by reducing the excitation current. Even with permanent magnet machines, there are known ways of generating an air gap field component by applying a suitable current to the stator of the machine. This air gap field component counteracts the excitation field generated by the permanent magnets and thus weakens it.However, this type of control of the machine results in increased losses, meaning the machine can only be operated at reduced efficiency in this range. An effective method for reducing iron losses in electrical machines is the targeted weakening of the magnetic field between the stator and rotor at high-speed operating points, since losses due to high-frequency remagnetization are lower in a weaker magnetic field. In addition to electrical methods, there are also mechanical approaches for targeted field weakening.Patents US58211710, FR2831345, EP1085644, EP11867030, DE1012011708670, DE1012016103470, CN104600929, and CN 105449969 disclose a rotor of a radial flux machine divided perpendicular to the rotation axis into several rotor disks equipped with permanent magnets that can be rotated relative to one another. Depending on the relative rotation between the rotor disks, the rotor provides the full magnetic field in a position with the magnetic poles aligned in the axial direction and a weakened magnetic field in a position rotated relative to the rotor disk. Active or passive mechanisms are described that claim to be able to switch between these two positions depending on the rotor speed or torque, thus enabling more efficient operation of the electric machine across the entire motor characteristic map.

[0007] DE 10 12021 101 898 describes an arrangement in which the rotor of a radial flux machine is divided into two sub-rotors, whose individual rotor disks alternate in the axial direction. One sub-rotor is connected directly to the rotor shaft, while the other sub-rotor is connected to the rotor shaft in a torque-transmitting manner via a torsional stiffness. The torsional stiffness is selected such that at low torques, the sub-rotors are in a torsional position with a weakened magnetic field, and at high torques, the sub-rotors are in a torsional position with a full magnetic field. DE 10 12021 101 904 claims a structurally designed mechanical module that can be inserted into the interior of the permanent-magnet-equipped rotor disks, establishes the described connections between the sub-rotors and the rotor shaft, and allows an adjustment characteristic to be defined via the torsional stiffness, which is implemented using springs and roller-equipped cam gears.All of the previously mentioned passive solutions, which use a torque as a sensor variable to trigger a relative rotation between two partial rotors against a torsional stiffness, assume that the total electromagnetic torque generated by the stator current in the case of the initially field-weakened position with non-aligned magnetic poles is simply distributed between the two partial rotors, roughly according to their share of the total length and their respective phase position to the stator field, regardless of the presence of the other partial rotor. Only then could a partial torque proportional to the total torque be readily directed against a torsional stiffness between the partial rotors or one of the partial rotors and the rotor shaft, and cause the desired rotation with increasing torque into the position with full magnetic field with aligned magnetic poles.However, tests and modelling by the applicant have shown that the actual circumstances are far more complicated.

[0008] Even in the de-energized state, interactions occur between the rotor disks of the two sub-rotors in the form of magnetic repulsion moments. The position with the full magnetic field and aligned magnetic poles represents a fragile equilibrium with a vanishing repulsion moment. As rotation begins from this equilibrium position, a repulsion moment arises that increases with increasing rotation until it reaches a maximum, before then decreasing again with further rotation. The progression of the repulsion moment over the angle of rotation within an electrical period, the height of the maximum, and the angle of rotation at which it occurs depend heavily on the chosen arrangement of the permanent magnets within the rotor disks. The progression over an electrical period is fundamentally non-linear.

[0009] In the case of the desired efficient stator current supply for different speeds, these magnetic repulsion moments increase in different ways, sometimes several times over, depending on the speed. Overall, the resulting partial moments are in no way suitable for simply counteracting the torsional rigidity between the partial rotors or one of the partial rotors and the rotor shaft, causing the partial rotors to rotate into the position with full magnetic field, since they are not directed in the correct direction due to the high proportion of magnetic repulsion moments.

[0010] For reliable adjustment behavior, it is necessary, among other things, that the end stops of a mechanical field weakening mechanism are precisely defined and designed to be reliable. In order to represent a functional arrangement in the sense of the aforementioned passive solutions for torque-adaptive field weakening of the rotor of an electrical machine, the object of the present invention is to provide a rotor and an electrical machine with improved mechanical field weakening. Furthermore, the object of the invention is to realize a kit of parts for forming a field weakening mechanism for a rotor of an electrical machine.

[0011] This object is achieved by a rotor for an electric machine, in particular for use within a drive train of a hybrid or fully electric motor vehicle, wherein the rotor has at least a first rotor body with a first group of permanent magnets and a second rotor body with a second group of permanent magnets, wherein the first rotor body and the second rotor body are rotatable relative to one another against the effect of a first torsional stiffness about a common axis of rotation by means of a mechanical field weakening mechanism, wherein the field weakening mechanism has a first mechanical stop which limits the rotation of the two rotor bodies relative to one another in a first circumferential direction and a second mechanical stop which limits the rotation of the two rotor bodies relative to one another in a second circumferential direction,The field weakening mechanism comprises a hub that is non-rotatably coupled to a rotor shaft of the rotor, the first rotor body being coupled to a first annular stop disk, and the second rotor body being coupled to a second annular stop disk, both the first stop disk and the second stop disk being positioned at an end of the first rotor body that protrudes from the rotor. This provides the advantage that the stops are arranged axially outside the rotor body, and the stop disks and the hub can be coupled to the rotor, in particular as a modular assembly, by axially sliding them onto the rotor shaft.

[0012] This provides the advantage of creating an electric machine with a purely mechanical field weakening device that reliably and cost-effectively adjusts the positions of permanent magnets within the rotor required for field weakening as required, depending on the operating conditions of torque and speed. The invention thus fundamentally eliminates the need for actuators that intervene externally on or in the rotor.

[0013] In principle, it would also be conceivable to position a second hub with associated stop discs at a second end protruding from the rotor. This would allow the stop system of the field weakening mechanism to be "mirrored," for example, to safely absorb higher stop forces.

[0014] The electric machine can, in particular, be designed as a rotary machine. In the case of electric machines designed as rotary machines, a distinction is made in particular between radial flux machines and axial flux machines. A radial flux machine is characterized by the fact that the magnetic field lines in the air gap formed between the rotor and stator extend in the radial direction, whereas in the case of an axial flux machine, the magnetic field lines in the air gap formed between the rotor and stator extend in the axial direction. In the context of this invention, it is possible for the electric machine to be configured as a radial flux machine or an axial flux machine.

[0015] A rotor is the rotating part of an electrical machine. The rotor comprises, in particular, a rotor shaft and one or more rotor bodies formed from rotor cores, arranged in a rotationally fixed manner on the rotor shaft. The rotor shaft can be hollow, which not only reduces weight but also allows the supply of lubricant or coolant to the rotor body.

[0016] For the purposes of the invention, a rotor body is understood to mean the rotor without the rotor shaft. The rotor body is therefore composed, in particular, of a rotor core and the permanent magnets incorporated into the pockets of the rotor core or fixed circumferentially to the rotor core, as well as any axial cover parts for closing the pockets.

[0017] The permanent magnets can preferably be incorporated into the pockets of the rotor core. A single larger rotor magnet designed as a bar magnet or several smaller permanent magnet elements can be provided per pocket.

[0018] The rotor has a plurality of rotor bodies. Particularly preferably, the rotor bodies are formed from substantially identical parts, in particular substantially identical. It is most preferred for the rotor bodies to be formed from identical, in particular substantially identical rotor laminations. The rotor bodies are therefore particularly preferably formed from a rotor lamination stack, which is composed of a plurality of laminated individual laminations or rotor laminations, generally made of electrical steel sheet, which are layered and stacked one on top of the other to form a stack, the so-called rotor lamination stack. The individual laminations can be held together in the rotor lamination stack by gluing, welding, or screwing. A rotor lamination stack can, in particular, also have permanent magnets introduced into the pockets of the rotor lamination stack or fixed circumferentially to the rotor lamination stack.

[0019] Mechanical field weakening mechanisms are generally known from the prior art. Particularly preferred mechanical field weakening mechanisms in connection with this invention are described in the as yet unpublished DE102022106944 and DE102022106945, as well as in the patent publications DE102021101904B3, DE102021101898A1, and DE102021101900A1, and are hereby incorporated by reference into the disclosure of this application.

[0020] It may further be preferred that the first rotor body and the second rotor body are rotatable relative to one another against the effect of a first torsional stiffness about a common axis of rotation by means of a mechanical field weakening mechanism, wherein the first torsional stiffness is designed as a first leg spring arrangement with a first leg spring which is coaxial to the axis of rotation and is arranged between the first rotor body and the second rotor body or between one of the rotor bodies and a rotor shaft in such a way that the rotation of one of the rotor bodies which begins when the field weakening mechanism is adjusted causes an opening or closing actuation of the first leg spring.

[0021] The formation of a torsional stiffness as a leg spring arrangement to define an adjustment characteristic to weaken the magnetic field by a relative rotation of the rotor bodies allows in particular the reduction of the centrifugal force influence on the adjustment characteristic and its hysteresis.

[0022] According to an advantageous embodiment of the invention, it can be provided that the hub has a plurality of hub teeth protruding outwards in the radial direction, which form / forms the first mechanical stop with the first stop disc and / or the second mechanical stop with the second stop disc. The advantage of this embodiment is that a stop can be defined in both circumferential directions by the teeth. Preferably, the hub has at least two hub teeth. Most preferably, the number of hub teeth is at least four. Furthermore, the hub teeth are preferably arranged equidistantly around the circumference of the hub. Most preferably, the hub teeth are essentially identical in shape.

[0023] According to a further preferred development of the invention, it can also be provided that the first stop disc has a plurality of first teeth projecting inwards in the radial direction, which together with at least one of the hub teeth form the first mechanical stop and / or the second stop disc has a plurality of second teeth projecting inwards in the radial direction, which together with at least one of the hub teeth form / form the second mechanical stop.

[0024] This makes it possible to design the stops in a particularly advantageous manner from a manufacturing perspective. In this context, it is preferred to produce a stop disc by stamping from a sheet metal. A stop disc preferably has at least two teeth. Most preferably, the number of teeth on a stop disc is at least four. Furthermore, the teeth are preferably distributed equidistantly around the circumference of a stop disc. Most preferably, the teeth on a stop disc are shaped essentially identically.

[0025] It is further preferred that the number of hub teeth corresponds to the number of teeth of one stop disc, preferably the number of teeth of both stop discs.

[0026] Furthermore, according to a likewise advantageous embodiment of the invention, it can be provided that the first stop disk has a plurality of first fastening openings, each of which is penetrated by a first fastening pin, wherein the first fastening pin axially penetrates the first rotor body, such that rotation of the first rotor body causes rotation of the first stop disk, and / or the second stop disk has a plurality of second fastening openings, each of which is penetrated by a second fastening pin, wherein the second fastening pin axially penetrates the second rotor body, such that rotation of the second rotor body causes rotation of the second stop disk. The first fastening pin and / or the second fastening pin can be designed in particular as a screw.

[0027] According to a further particularly preferred embodiment of the invention, it can be provided that the first stop disk has a plurality of first through-openings through which one of the second fastening pins passes, and the first through-openings are designed such that the second fastening pins do not restrict relative rotation of the first stop disk to the second stop disk, and / or the second stop disk has a plurality of second through-openings through which one of the first fastening pins passes, and the second through-openings are designed such that the first fastening pins do not restrict relative rotation of the first stop disk to the second stop disk. As a result, the two stop disks can rotate freely relative to one another, with the stop in the circumferential direction then being provided solely by the teeth of the hub and the stop disks.

[0028] Furthermore, the invention can also be further developed in such a way that the rotationally fixed connection between the rotor shaft and the hub is formed by means of a spline. The advantage of this design is that the hub can be slid onto the rotor shaft particularly easily, while still achieving a sufficiently high torque transmission capacity.

[0029] In a likewise preferred embodiment of the invention, the hub can also be arranged axially outside the first rotor body and the second rotor body on the rotor shaft. This makes the hub particularly easy to install, as it is not necessary to insert it into the rotor body. This also facilitates the modular design of the hub and the stop discs.

[0030] It may also be advantageous to further develop the invention in such a way that the first fastening pins and / or the second fastening pins are designed as screws.

[0031] The object of the invention is further achieved by an electric machine, in particular for use within a drive train of a hybrid or fully electric motor vehicle, comprising a rotor according to one of claims 1-8. Finally, the object of the invention can also be achieved by a kit of parts for forming a field weakening mechanism of a rotor of an electric machine, comprising

[0032] • a hub which can be coupled in a rotationally fixed manner to a rotor shaft of the rotor of the electric machine,

[0033] • a first ring-like stop disc which can be coupled to a first rotor body of the rotor and

[0034] • a second ring-like stop disc which can be coupled to a second rotor body of the rotor,

[0035] • wherein both the first stop disc and the second stop disc are positionable at an end of the first rotor body pointing out of the rotor, wherein a first mechanical stop is formed between the hub and the first stop disc and a second mechanical stop is formed between the hub and the second stop disc.

[0036] This allows the components required to manufacture the field-weakening mechanism to be provided in a particularly convenient manner. The kit of parts can, for example, be a single packaging unit. Furthermore, it is possible to design the kit of parts as a collection of separate storage containers for storing the individual components or the respective component groups of the kit of parts.

[0037] The invention will be explained in more detail below with reference to figures without limiting the general inventive concept.

[0038] It shows: Figure 1 an electrical machine in a cross-sectional view,

[0039] Figure 2 is a schematic block diagram of a rotor with a mechanical field weakening mechanism

[0040] Figure 3 shows a rotor in a first axial sectional view,

[0041] Figure 4 shows a rotor in a second axial section view,

[0042] Figure 5 shows a first stop disc and a second stop disc in a front view,

[0043] Figure 6 shows a hub in a perspective view,

[0044] Figure 7 shows a rotor shaft in a perspective view,

[0045] Figure 8 shows the first stop disc, second stop disc and hub in a first operating position in a front view,

[0046] Figure 9 the first stop disc, second stop disc and hub in a second operating position in a front view,

[0047] Figure 10 the first stop disc, second stop disc and hub in a third operating position in a frontal view.

[0048] Figure 1 shows an electric machine 1, in particular for use within a drive train of a hybrid or fully electric motor vehicle. The electric machine 1, configured 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 group of permanent magnets 6 and a second rotor body 7 with a second group of permanent magnets 8, which can be clearly seen from the combination of Figure 1 and Figure 2. The first rotor body 5 and the second rotor body 7 can be rotated relative to one another about a common axis of rotation 10 by means of a mechanical field weakening mechanism 11, counter to the effect of a first torsional stiffness 9.The two rotor bodies 5,7 are essentially formed from identical rotor laminations, wherein the position and number of permanent magnets 6 of the first group and the number of permanent magnets 8 of the second group in the rotor bodies 5,7 are identical.

[0049] The field weakening mechanism 11 shown as an example in Figure 2 comprises a lever element (not further identified) that can be pivoted about a pivot point, wherein the first rotor body 5 can be coupled to a first lever section and the second rotor body 7 can be coupled to a second lever section of the lever element. The first lever section and the second lever section are arranged on opposite sides of the lever, so that the first rotor body 5 and the second rotor body 7 can be rotated relative to one another by tilting the lever element for a desired adjustment of the mechanical field weakening mechanism 11. This field weakening mechanism 11 is described in detail in DE102022106944 and DE102022106945, so that reference is made here to these documents to avoid repetition.

[0050] The first torsional stiffness 9 is designed as a first leg spring arrangement with a first leg spring, which is arranged coaxially to the rotational axis 10 and between the first rotor body 5 and the second rotor body 7 in such a way that the rotation of one of the rotor bodies 5, 7 that occurs during the adjustment of the field weakening mechanism 11 causes an opening or closing actuation of the first leg spring. Even if not shown in Figures 2-3, it is nevertheless possible for the first leg spring to be arranged between one of the rotor bodies 5, 7 and the rotor shaft 14 in a torque-transmitting manner.

[0051] Figure 3 shows an embodiment of a rotor 4 for an electrical machine 1, wherein the rotor 4 has a 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 one another about a common axis of rotation 10 by means of a mechanical field weakening mechanism 11, counter to the effect of a first torsional stiffness 9. In the exemplary embodiment shown, a total of four first rotor bodies 5 and three second rotor bodies 7 are present in the rotor 4, wherein the first rotor bodies 5 each form the axial end of the rotor 4.

[0052] The field weakening mechanism 11 has a first mechanical stop 12 which limits the rotation of the two rotor bodies 5,7 relative to each other in a first circumferential direction and a second mechanical stop 13 which limits the rotation of the two rotor bodies 5,7 relative to each other in a second circumferential direction, which can be clearly seen from Figures 9-10.

[0053] The field weakening mechanism 11 further comprises a hub 16 which is non-rotatably coupled to a rotor shaft 14 of the rotor 4. The first rotor body 5 is coupled to a first annular stop disk 17 and the second rotor body 7 is coupled to a second annular stop disk 15. Both the first stop disk 17 and the second stop disk 15 are positioned at an end of the first rotor body 5 pointing out of the rotor 4, as can be clearly seen in Figures 3-4. What can also be clearly seen in Figures 3-4 is that the hub 16 is arranged axially outside the first rotor body 5 and the second rotor body 7 on the rotor shaft 14.

[0054] Figure 6 shows that the hub 16 has four hub teeth 18 projecting outwards in the radial direction, which, together with the first stop disk 17, form the first mechanical stop 12 and / or, together with the second stop disk 15, form the second mechanical stop 13. Figure 5 shows that the first stop disk 17 has four first teeth 20 projecting inwards in the radial direction, which, together with at least one of the hub teeth 18, form the first mechanical stop 12. The second stop disk 15 also has a plurality of second teeth 19 projecting inwards in the radial direction, which, together with at least one of the hub teeth 18, form the second mechanical stop 13.

[0055] The first stop disk 17 has a plurality of first circular fastening openings 23, each of which is penetrated by a first fastening pin 24, wherein the first fastening pin 24 axially penetrates the first rotor body 5, so that a rotation of the first rotor body 5 causes a rotation of the first stop disk 17. Analogously, the second stop disk 15 also has a plurality of second circular fastening openings 21, each of which is penetrated by a second fastening pin 22, wherein the second fastening pin 22 axially penetrates the second rotor body 7, so that a rotation of the second rotor body 7 causes a rotation of the second stop disk 15.

[0056] The first stop disc 17 further comprises a plurality of first elongated hole-like through-openings 26, through which one of the second fastening pins 22 extends. The first through-openings 26 are designed such that the second fastening pins 22 do not restrict relative rotation of the first stop disc 17 to the second stop disc 15. The same applies analogously to the second stop disc 15, which likewise comprises a plurality of second, elongated hole-like through-openings 25, through which one of the first fastening pins 24 extends, and the second through-openings 25 are likewise designed such that the first fastening pins 24 do not restrict relative rotation of the first stop disc 17 to the second stop disc 15.

[0057] The first fastening pins 24 and the second fastening pins 22 are each designed as screws. The screws are preferably identical.

[0058] A look at Figures 6-7 together shows that the rotationally fixed connection between the rotor shaft 14 and the hub 16 is formed by means of a spline 29. Figure 8 shows the rotor 4 in a field-weakened, neutral position, without a moment acting between the rotor bodies 5, 7. It can be clearly seen that in this operating situation the hub teeth 18 do not have a stop with the first stop disk 17 and the second stop disk 15. Figure 9 shows the rotor 4 in a field-strengthened, tensile position. In this case, the rotor bodies 5, 7 and their associated stop disks 15, 17 are rotated relative to one another until the hub teeth 18, together with the teeth 19, 20 of the stop disks 15, 17, form a first stop 12, which, viewed from the hub teeth 18, lies on the counterclockwise flank of the hub teeth 18.Figure 10 shows the rotor 4 in a field-strengthened, thrust-loaded position, in which the rotor bodies 5, 7 and the stop disks 15, 17 assigned to them are rotated relative to one another until the hub teeth 18, together with the teeth 19, 20 of the stop disks 15, 17, form a second stop 13, which, viewed from the hub teeth 18, lies on the flank of the hub teeth 18 pointing in the clockwise direction.

[0059] The invention is not limited to the embodiments illustrated in the figures. The above description is therefore not to be considered restrictive, but rather explanatory. The following claims are to be understood in such a way that a stated feature is present in at least one embodiment of the invention. This does not exclude the presence of further features. Where the claims and the above description define 'first' and 'second' features, this designation serves to distinguish between two similar features without establishing a priority.

[0060] List of reference symbols

[0061] 1 electric machine

[0062] 2 Stator

[0063] 3 Air gap

[0064] 4 Rotor

[0065] 5 rotor bodies

[0066] 6 permanent magnets

[0067] 7 Rotor body

[0068] 8 permanent magnets

[0069] 9 Torsional stiffness

[0070] 10 axis of rotation

[0071] 11 Field weakening mechanism

[0072] 12 stops

[0073] 13 stop

[0074] 14 Rotor shaft

[0075] 15 Stop disc

[0076] 16 Hub

[0077] 17 Stop disc

[0078] 18 hub teeth

[0079] 19 teeth

[0080] 20 teeth

[0081] 21 mounting holes

[0082] 22 Fixing pin

[0083] 23 mounting holes

[0084] 24 fixing pin

[0085] 25 access openings

[0086] 26 access openings

[0087] 29 spline

Claims

Claims 1. A rotor (4) for an electric machine (1), in particular for use within a drive train of a hybrid- or fully electric-powered motor vehicle, wherein the rotor (4) has at least a 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) are rotatable relative to one another about a common axis of rotation (10) by means of a mechanical field weakening mechanism (11) against the effect of a first torsional stiffness (9), wherein the field weakening mechanism (11) has a first mechanical stop (12) that limits the rotation of the two rotor bodies (5, 7) relative to one another in a first circumferential direction and a second mechanical stop (13) that limits the rotation of the two rotor bodies (5, 7) relative to one another in a second circumferential direction,characterized in that the field weakening mechanism (11) has a hub (16) which is non-rotatably coupled to a rotor shaft (14) of the rotor (4), wherein the first rotor body (5) is coupled to a first annular stop disc (17) and the second rotor body (7) is coupled to a second annular stop disc (15), wherein both the first stop disc (17) and the second stop disc (15) are positioned at an end of the first rotor body (5) pointing out of the rotor (4).

2. Rotor (4) according to claim 1, characterized in that the hub (16) has a plurality of hub teeth (18) projecting outwards in the radial direction, which, with the first stop disc (17), engage the first mechanical stop (12) and / or with the second stop disc (15) forms / forms the second mechanical stop (13).

3. Rotor (4) according to claim 1 or 2, characterized in that the first stop disc (17) has a plurality of first teeth (20) projecting inwards in the radial direction, which together with at least one of the hub teeth (18) form the first mechanical stop (12) and / or the second stop disc (15) has a plurality of second teeth (19) projecting inwards in the radial direction, which together with at least one of the hub teeth (18) form the second mechanical stop (13).

4. Rotor (4) according to one of the preceding claims, characterized in that the first stop disc (17) has a plurality of first fastening openings (23), each of which is penetrated by a first fastening pin (24), wherein the first fastening pin (24) axially penetrates the first rotor body (5) so that a rotation of the first rotor body (5) causes a rotation of the first stop disc (17) and / or the second stop disc (15) has a plurality of second fastening openings (21), each of which is penetrated by a second fastening pin (22), wherein the second fastening pin (22) axially penetrates the second rotor body (7) so that a rotation of the second rotor body (7) causes a rotation of the second stop disc (15).

5. Rotor (4) according to claim 4, characterized in that the first stop disc (17) has a plurality of first through-openings (26) through which one of the second fastening pins (22) passes, and the first through-openings (26) are designed such that the second fixing pins (22) a relative rotation of the first Stop disc (17) to the second stop disc (15), and / or the second stop disc (15) has a plurality of second through-openings (25) through which one of the first fastening pins (24) passes, and the second through-openings (25) are designed such that the first fastening pins (24) do not restrict a relative rotation of the first stop disc (17) to the second stop disc (15).

6. Rotor (4) according to one of the preceding claims, characterized in that the rotationally fixed connection between the rotor shaft (14) and the hub (16) is formed by means of a spline (29).

7. Rotor (4) according to one of the preceding claims, characterized in that the hub (16) is arranged axially outside the first rotor body (5) and the second rotor body (7) on the rotor shaft (14).

8. Rotor (4) according to one of the preceding claims, characterized in that the first fastening pins (24) and / or the second fastening pins (22) are designed as screws.

9. Electrical machine (1), in particular for use within a drive train of a hybrid or fully electrically powered motor vehicle, comprising a rotor (4) according to one of the preceding claims.

10. Kit-of-parts for forming a field weakening mechanism (11) of a rotor (4) of an electrical machine (1) comprising - a hub (16) which can be coupled in a rotationally fixed manner to a rotor shaft (14) of the rotor (4) of the electrical machine (1), - a first annular stop disc (17) which can be coupled to a first rotor body (5) of the rotor (4) and - a second annular stop disc (15) which can be coupled to a second rotor body (7) of the rotor (4), wherein both the first stop disc (17) and the second Stop disc (15) can be positioned at an end of the first rotor body (5) pointing out of the rotor (4), wherein a first mechanical stop (12) can be formed between the hub (16) and the first stop disc (17) and a second mechanical stop (13) can be formed between the hub (16) and the second stop disc (15).

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