Rotor for an electric machine of a motor vehicle, and electric machine for a motor vehicle

Abstract

The invention relates to a rotor (1) for an electric machine of a motor vehicle, having: a rotor shaft (5); a laminated core (3) arranged on the rotor shaft (5) and connected to the rotor shaft (5) for conjoint rotation; at least one star disc (12) which is arranged on an axial end side of the laminated core (3) and by which end windings (7), protruding axially from the end side, of rotor windings (4), carried by the laminated core (3), of the rotor (1) are at least partially covered towards the outside in a radial direction (9) of the rotor (1); and a support ring (13) by which the star disc (12) is at least partially encased, comprising an annular channel (18) which is arranged between the rotor shaft (5) and the support ring (13) in the radial direction (9) of the rotor (1) and into which there leads at least one channel (19) which extends in the rotor shaft (5) and through which a lubricant and / or coolant is able to flow.

Description

[0001] Rotor for an electric machine of a motor vehicle and electric machine for a motor vehicle

[0002] The invention relates to a rotor for an electric machine of a motor vehicle, in particular a motor car, according to the preamble of patent claim 1. Furthermore, the invention relates to an electric machine for a motor vehicle, in particular for a motor car.

[0003] WO 2015 / 150109 A1 discloses a rotor element designed to be arranged on a current-excited rotor of an electric machine. DE 102019205 101 A1 discloses a method for producing an electromechanical component for an electric machine from a laminated core, wherein the laminated core has a plurality of pole teeth. Furthermore, DE 102018 128 521 A1 discloses a support device for a rotor of a separately excited internal rotor synchronous machine of an electrically driven motor vehicle, comprising a star disk that can be arranged on a laminated core of the rotor between an end face of the laminated core and winding overhangs of rotor windings of the rotor projecting from the end face. The support device also has a support ring for encasing the star disk.

[0004] The object of the present invention is to provide a rotor for an electric machine of a motor vehicle and an electric machine for a motor vehicle, so that a particularly advantageous cooling of the rotor can be realized.

[0005] This object is achieved according to the invention by a rotor having the features of patent claim 1 and by an electric machine having the features of patent claim 10. Advantageous embodiments of the invention are the subject of the dependent claims.

[0006] A first aspect of the invention relates to a rotor for an electric machine of a motor vehicle, also simply referred to as a vehicle. This means that the motor vehicle, which is preferably designed as a motor vehicle, in particular as a passenger car, and also simply referred to as a vehicle, has the electric machine and thus the rotor in its fully manufactured state. The electric machine has the rotor and, for example, a stator, by means of which the rotor can be driven and is therefore rotatable about a machine axis of rotation relative to the stator. In particular, the electric machine can provide drive torques via its rotor for driving the motor vehicle, which can thus be driven by means of the electric machine, in particular purely electrically.Thus, the motor vehicle is preferably designed as a hybrid vehicle or as an electric vehicle, in particular as a battery-electric vehicle (BEV). The electric machine is preferably a high-voltage component whose electrical voltage, in particular the operating and rated voltage, is preferably greater than 50 volts, in particular greater than 60 volts, and most preferably amounts to several hundred volts. For example, the electric machine is designed as a current-excited synchronous machine (SSM), in particular as a current-excited or separately excited internal rotor synchronous machine.

[0007] The rotor has a rotor shaft, also simply referred to as a shaft, via which, for example, the electric machine can provide the aforementioned drive torques. Furthermore, the rotor has a laminated core arranged on the rotor shaft and connected to the rotor shaft in a rotationally fixed manner. The rotor also has at least one star disk, which is arranged, in particular directly, on an axial end face of the laminated core. Thus, in the axial direction of the rotor, the star disk adjoins the laminated core, in particular directly, and thereby adjoins the axial end face of the laminated core, in particular in such a way that the star disk bears, in particular directly, against the axial end face of the laminated core. The axial direction of the rotor and thus of the electric machine as a whole coincides with the machine axis of rotation.In particular, the axial end face of the laminated core is understood to be that side of the laminated core whose axial end face extends in a plane perpendicular to the axial direction of the rotor, and whose radial direction is perpendicular to the axial direction and thus perpendicular to the machine's rotational axis. The star disk, for example, is part of a support device of the rotor, which support device will be explained in more detail below.

[0008] The star disk covers, i.e., overlaps, the winding heads of rotor windings supported by the laminated core, which protrude axially from the end face in the axial direction of the rotor. The rotor windings are supported by the laminated core and are covered, i.e., overlapped, at least partially, in particular at least predominantly and thus more than half or completely, in the radial direction of the rotor. The rotor also has a support ring, by which the star disk is at least partially encased. The support ring is, for example, a further component of the support device. The star disk and the support ring are preferably separately formed and interconnected components.In particular, it is provided that the star disk and the laminated core are formed separately from one another, and very preferably the support ring and the laminated core are formed separately from one another, so that preferably the support ring, the star disk and the laminated core, especially when viewed in pairs, are components formed separately from one another. The support ring and the star disk are at least indirectly rotationally connected to the rotor shaft, so that the rotor shaft, the laminated core, the star disk and the support ring are jointly rotatable about the axis of rotation relative to the stator. In other words, the laminated core, the star disk and the support ring are rotatable with the rotor shaft, in particular about the machine axis of rotation and relative to the stator.The support ring in particular at least partially encloses the star disk in such a way that the star disk is at least partially, in particular at least predominantly and thus more than half or completely, overlapped and thus covered by the support ring in the radial direction of the star disk towards the outside. Furthermore, it is conceivable that the star disk is at least partially, in particular at least predominantly and thus more than half or completely, overlapped and thus covered by the support ring in the axial direction of the star disk and thus in the axial direction of the rotor, in particular in a direction coinciding with the axial direction of the star disk and pointing away from the axial end face of the laminated core. In particular, it is provided that the star disk can be or is supported at least indirectly, in particular directly, on the support ring towards the outside in the radial direction of the rotor.

[0009] For example, the star disk has a ring carrier which is arranged, in particular directly, on a rotor yoke of the laminated core. In other words, the ring carrier is arranged, in particular directly and / or in the axial direction of the rotor and thus in the axial direction of the laminated core, on the rotor yoke of the laminated core. Expressed again in other words, the ring carrier is arranged in the axial direction of the laminated core and thus in the axial direction of the rotor and in the axial direction of the star disk, in particular directly, on a first part of the axial end face of the laminated core, wherein the first part of the axial end face of the laminated core is formed by the rotor yoke of the laminated core. For example, the ring carrier has a through-opening in which at least a longitudinal region of the rotor shaft is arranged, in particular such that the rotor shaft penetrates the through-opening.For example, it is conceivable that the ring carrier and thus the star disk are connected to the rotor shaft via the ring carrier, in particular by means of a press fit.

[0010] The star disk further comprises, for example, support teeth which protrude outwards from the ring carrier in the radial direction of the star disk and thus of the rotor. The support teeth are spaced apart from one another, in particular evenly, in the circumferential direction of the rotor running around the axial direction of the rotor and thus around the machine rotation axis, in particular such that the support teeth are evenly arranged in the circumferential direction of the star disk and the rotor running around the axial direction of the rotor. As a result, for example, viewed in the circumferential direction of the rotor and thus of the star disk, a respective groove is formed between two support teeth which are immediately adjacent in the circumferential direction of the rotor and thus of the star disk, which groove is also referred to as a rotor groove.The support teeth are arranged, for example, in particular directly, on rotor teeth of the laminated core that protrude radially from the rotor yoke, i.e., in the radial direction of the rotor and thus of the laminated core and the star disk, the rotor teeth of which support the rotor windings. In particular, the support teeth are arranged, for example, in particular directly, on the rotor teeth of the laminated core that protrude radially from the rotor yoke in such a way that the support teeth are arranged between the respective rotor teeth and the winding overhangs, in particular in the axial direction of the star disk and thus of the laminated core and the rotor.The rotor windings are, for example, wound around the rotor teeth and are thereby supported by the rotor teeth and thus the laminated core in such a way that the rotor windings extend through the slots between the supporting teeth and in particular through further slots, also referred to as laminated core slots, which are arranged in the circumferential direction of the laminated core and thus of the rotor between rotor teeth, in particular in such a way that, viewed in the circumferential direction of the rotor and thus of the laminated core running around the axial direction of the rotor, a respective laminated core slot is arranged between each two rotor teeth of the laminated core that are immediately adjacent in the circumferential direction of the rotor.Thus, it is preferably provided that the rotor teeth are arranged spaced from one another in the circumferential direction of the rotor, wherein it can in particular be provided that the rotor teeth of the laminated core are arranged evenly distributed in the circumferential direction of the laminated core and thus of the rotor. Thus, for example, the rotor yoke is overlapped by the ring carrier in the axial direction of the laminated core and thus of the rotor, wherein the rotor teeth are overlapped by the support teeth in the axial direction of the rotor and thus of the laminated core. The rotor windings form the winding heads, which protrude from the laminated core in the axial direction of the rotor and thus from the axial end face of the laminated core, and thus project beyond the axial end face of the laminated core in the axial direction of the rotor. For example, the support teeth of the star disk are at least partially wrapped by the winding heads.In particular, the support teeth are arranged, for example, in the axial direction of the star disk and thus of the rotor between the axial end face and the winding heads. Roof regions of the star disk protrude, for example, in the axial direction of the rotor from the support teeth, for example from the outer or outermost ends of the support teeth, in particular in the axial direction of the rotor, in particular in such a way that the roof regions protrude from the ends of the support teeth in the aforementioned direction, which coincides with the axial direction of the star disk and thus of the rotor and points away from the axial end face. The roof regions are arranged, for example, in the axial direction of the star disk and thus of the rotor, in particular directly, on pole shoes of the laminated core protruding from the rotor teeth.For example, respective third parts of the axial end face of the laminated core are formed by the pole shoes of the laminated core, so that, for example, the roof regions are supported, in particular in the axial direction of the rotor and / or directly, on the third part of the axial end face. The roof regions at least partially, in particular at least predominantly or completely, overlap and thus cover the winding heads in the radial direction of the rotor towards the outside, so that the winding heads can be or are supported at least indirectly, in particular directly, on the roof regions towards the outside in the radial direction of the star disk. The roof regions are also referred to as end pieces, which, for example, are collar-like or protrude like a collar from the ends of the supporting teeth.The roof areas are used in particular to absorb or support centrifugal forces acting on the winding heads, i.e. in particular centrifugal forces acting outwards on the winding heads in the radial direction of the rotor, in order to avoid, for example, excessive deformation of the winding heads.

[0011] In order to be able to achieve particularly advantageous cooling of the rotor, the invention provides that the rotor has an annular channel arranged in the radial direction of the rotor between the rotor shaft and the support ring, which is delimited, for example, in the radial direction of the rotor outwards, in particular directly, by the support ring, in particular an inner circumferential surface of the support ring, and in the radial direction of the rotor inwards, in particular directly, by the rotor shaft, in particular an outer circumferential surface of the rotor shaft. The annular channel runs completely around the circumferential direction of the rotor running around the axial direction of the rotor. In other words, the annular channel runs completely closed between the support ring and the rotor shaft, viewed in the circumferential direction of the rotor.At least one channel, which is preferably liquid and through which a lubricant and / or coolant can flow and which runs in the rotor shaft, opens into the annular channel, in particular directly and is also referred to as a supply channel. In particular, the channel opens into the annular channel via at least one or precisely one outlet opening of the channel in such a way that the outlet opening of the channel, through which the lubricant and / or coolant can flow, is at least partially, in particular at least predominantly and thus at least more than half or completely overlapped in the radial direction of the rotor towards the outside by the support ring, in particular by the inner circumferential surface of the support ring. For example, the rotor shaft is designed as a hollow shaft, so that, for example, the rotor shaft has at least one hollow longitudinal region through which at least part of the channel is formed.The annular channel can be supplied with the lubricant and / or coolant via the channel through which the lubricant and / or coolant can flow and which runs inside the rotor shaft.

[0012] Preferably, the lubricant and / or coolant is a component of the rotor. Most preferably, the lubricant and / or coolant is a liquid. For example, the lubricant and / or coolant is an oil.

[0013] Because the channel (supply channel) opens into the annular channel, in particular via its outlet opening and in particular directly, the lubricant and / or coolant flowing through the channel can flow through the outlet opening and thus flow out of the channel and thereby flow, in particular directly, into the annular channel, whereby the annular channel can be or is supplied with the lubricant and / or coolant. From the annular channel, the lubricant and / or coolant with which the annular channel was supplied can flow along the support ring, in particular along a second axial end face of the support ring, also referred to as the support ring end face, in particular when the rotor rotates about the machine axis of rotation relative to the stator during operation of the electric machine, so that centrifugal forces act on the lubricant and / or coolant in the annular channel outwards in the radial direction of the rotor.In this case, for example, the second axial end face of the support ring faces away from the first axial end face of the laminated core in the axial direction. Since the lubricant and / or coolant flows or can flow from the annular channel, in particular directly along the support ring end face, the support ring end face can be cooled particularly advantageously, so that particularly advantageous end face cooling of the support ring and thus of the rotor can be achieved. In particular, because the lubricant and / or coolant flows or can flow from the annular channel, in particular directly along the support ring end face, heat can be transferred from the support ring and thus from the rotor to the lubricant and / or coolant flowing along the support ring end face, whereby particularly good cooling can be achieved.By means of the annular channel, the lubricant and / or coolant from the annular channel can be distributed particularly advantageously, in particular at least substantially uniformly, on the support ring end face, in particular during rotation of the rotor, so that the support ring end face can be wetted and thus supplied with the lubricant and / or coolant in a particularly advantageous manner, in particular over a particularly large area.

[0014] The background of the invention is, in particular, that rotor cooling can be crucial for the continuous electrical performance of the electric machine. Since the invention enables particularly advantageous cooling of the support ring face and thus of the rotor, a particularly high continuous output of the electric machine can be achieved. The invention enables particularly advantageous, in particular particularly large-area, wetting of the support ring face, also referred to as the face or designed as the face, with the lubricant and / or coolant from the annular channel, thus ensuring particularly advantageous heat dissipation from the rotor.

[0015] In order to be able to supply the support ring end face with the lubricant and / or coolant via the annular channel in a particularly advantageous manner, one embodiment of the invention provides that the annular channel is directly delimited by the inner circumferential surface of the support ring in the radial direction of the rotor shaft outwards and thus in a direction running in the radial direction of the rotor and pointing away from the rotor shaft. The inner circumferential surface of the support ring is or forms, for example, an edge or edge region of the support ring, also referred to as the annular channel edge, which ends inwards at the edge, particularly in the radial direction of the rotor shaft and thus of the rotor.The annular channel is delimited outwards in the radial direction of the rotor and thus of the rotor shaft, i.e. in the previously mentioned direction, also referred to as the first direction, running in the radial direction of the rotor and thus of the rotor shaft and pointing away from the rotor shaft, in particular directly, by the edge of the support ring. It has proven particularly advantageous if the inner circumferential surface, i.e. the edge of the support ring, viewed in a plane also referred to as the viewing plane, in which the axial direction of the rotor shaft and thus the machine axis of rotation runs, is convex, i.e. curved inwards in the radial direction and thus towards the rotor shaft. This allows the lubricant and / or coolant to flow out of the annular channel particularly advantageously and in particular directly along the edge of the support ring and subsequently along the end face of the support ring, whereby particularly advantageous heat dissipation can be achieved.

[0016] A further embodiment is characterized in that the inner circumferential surface of the support ring has a first partial region and a second partial region which adjoins the first partial region in the axial direction of the rotor shaft and thus of the rotor and directly adjoins the first partial region toward the laminated core, and which is set back outwardly relative to the first partial region in the radial direction of the rotor shaft and thus of the rotor. Thus, for example, the annular channel has a first depth running in the radial direction of the rotor shaft and thus of the rotor, which extends in the radial direction of the rotor shaft between the outer circumferential surface of the rotor shaft and the first partial region of the inner circumferential surface.In addition, for example, the annular channel has a second depth which runs in the radial direction of the rotor shaft and thus of the rotor and is greater than the first depth. This second depth extends in the radial direction of the rotor shaft and thus of the rotor between the second partial region of the inner circumferential surface and the outer circumferential surface of the rotor shaft. On the one hand, this allows the lubricant and / or coolant from the channel (supply channel) to collect particularly advantageously initially in the annular channel, in particular in the second partial region, whereupon the lubricant and / or coolant from the annular channel, in particular from the second partial region, can flow via the first partial region to and then along the support ring end face. This allows particularly advantageous cooling of the rotor to be achieved.

[0017] In order to be able to supply the support ring end face particularly advantageously with the lubricant and / or coolant from the annular channel, it is provided in a further embodiment of the invention that the inner circumferential surface of the support ring is convexly curved at least in the first partial area when viewed in the said viewing plane.

[0018] In a further, particularly advantageous embodiment of the invention, it is provided that the channel opens into the annular channel via the at least one outlet opening of the channel, whereby a particularly advantageous supply of the annular channel and, via the annular channel, the support ring end face with the lubricant and / or coolant can be ensured.

[0019] It has proven particularly advantageous if the outlet opening in the radial direction of the rotor shaft is at least predominantly overlapped outwards, i.e. at least more than half or even completely, by the second partial region. As a result, the lubricant and / or coolant flowing through the outlet opening and thus flowing out of the channel via the outlet opening can initially flow directly into the second partial region of the annular channel and be guided, so that, for example, the lubricant and / or coolant from the channel can initially collect in the second partial region. In particular, due to the centrifugal forces, the lubricant and / or coolant can then flow from the second partial region into the first partial region, whereupon the lubricant and / or coolant can flow from the first partial region to and along the support ring end face.This ensures particularly effective and efficient cooling of the support ring face and thus of the rotor.

[0020] For example, the channel opens into the annular channel via a plurality of outlet openings of the channel. Preferably, the outlet openings of the channel are arranged consecutively and spaced apart from one another in the circumferential direction of the rotor shaft and thus of the rotor, extending around the axial direction of the rotor shaft and thus of the rotor. Preferably, the outlet openings of the channel are evenly distributed in the circumferential direction of the rotor and thus of the rotor shaft. This allows for at least substantially uniform wetting of the support ring face with the lubricant and / or coolant from the annular channel.

[0021] The respective outlet opening is, for example, a bore in the rotor shaft, wherein the bore is formed by machining. In other words, drilling is to be understood as a machining process. Furthermore, it is conceivable for the respective outlet opening to run in the radial direction of the rotor and thus to be flowed through by the lubricant and / or coolant in the radial direction, so that, for example, the lubricant and / or coolant can be discharged from the respective outlet opening in the radial direction of the rotor and thus introduced into the respective first longitudinal region. This can achieve particularly advantageous wetting of the support ring end face and thus particularly advantageous cooling of the support ring and thus of the rotor.

[0022] In a further embodiment of the invention, it is provided that the annular channel is delimited in the radial direction of the rotor shaft and thus of the rotor inwards directly by the outer circumferential surface of the rotor shaft.

[0023] In order to be able to guide the lubricant and / or coolant particularly as needed and thus achieve a particularly advantageous supply of the support ring end face with the lubricant and / or coolant, a further embodiment of the invention provides that the rotor shaft has a first shaft element in which at least a first longitudinal region of the channel runs. The rotor shaft has a second shaft element which is formed separately from the first shaft element, arranged on the first shaft element and connected to the first shaft element in a rotationally fixed manner. A second longitudinal region of the channel runs in the second shaft element, in particular directly adjoining the first longitudinal region.The second longitudinal region of the channel is fluidically connected to the first longitudinal region of the channel, such that the lubricant and / or coolant can first flow through the first longitudinal region on its way through the channel and then flow out of the first longitudinal region and into the second longitudinal region and then flow through the second longitudinal region. Thus, it is preferably provided that the second longitudinal region is arranged downstream of the first longitudinal region in the flow direction of the lubricant and / or coolant flowing through the channel and towards the annular channel. Thus, for example, the second longitudinal region has the outlet opening, such that in particular the channel opens into the annular channel via the second longitudinal region and in particular via the outlet opening of the second longitudinal region. In this case, it is particularly provided that the channel ends at the outlet opening of the second longitudinal region.In this case, it is preferably provided that the outer circumferential surface of the rotor shaft, which delimits the annular channel inwardly in the radial direction of the rotor shaft and thus of the rotor, is formed, in particular completely, by the second shaft element. As a result, for example, a particularly outer circumferential shape of the second shaft element, i.e. in particular a shape of the outer circumferential surface, can be selected and implemented as required without, for example, undesirably influencing the first shaft element. This ensures a particularly advantageous supply of the lubricant and / or coolant to the annular channel and consequently to the support ring end face, so that the support ring and thus the rotor can be advantageously cooled via the support ring end face.

[0024] A second aspect of the invention relates to an electric machine for a motor vehicle, also simply referred to as a vehicle, and preferably designed as a motor vehicle, in particular a passenger car, having a stator and a rotor according to the first aspect of the invention. Advantages and advantageous embodiments of the first aspect of the invention are to be regarded as advantages and advantageous embodiments of the second aspect of the invention, and vice versa.

[0025] Further details of the invention emerge from the following description of preferred embodiments with the associated drawings.

[0026] It shows:

[0027] Fig. 1 shows a partial schematic perspective view of a rotor of an electric machine for a motor vehicle; and

[0028] Fig. 2 shows a schematic and partially sectioned

[0029] Perspective view of the rotor;

[0030] Fig. 3 shows a partial schematic and sectional perspective view of a first embodiment of the rotor; and

[0031] Fig. 4 shows a partial schematic and sectional perspective view of a second embodiment of the rotor.

[0032] In the figures, identical or functionally identical elements are provided with the same reference symbols.

[0033] Fig. 1 shows a section in a schematic perspective view of a rotor 1 for an electric machine of a motor vehicle, also simply referred to as a vehicle. This means that the motor vehicle, which is preferably designed as a motor vehicle, in particular as a passenger car, in its fully manufactured state has the electric machine and thus the rotor 1 and can be driven by means of the electric machine, in particular purely electrically. The electric machine has the rotor 1 and a stator (not shown in the figures), by means of which the rotor 1 can be driven and is therefore rotatable about a machine axis of rotation 2 relative to the stator. The rotor 1, the axial direction of which coincides with the machine axis of rotation 2, has a laminated core 3 and rotor windings 4 which are carried by the laminated core 3. The rotor windings 4 are formed, for example, by winding wires.Thus, the electric machine is, for example, an externally excited or current-excited machine, in particular an externally excited or current-excited synchronous machine (SSM). For example, the laminated core 3, also referred to as the rotor core, is constructed from several individual laminations, which are arranged one behind the other, in particular in the axial direction of the laminated core 3 and thus of the rotor 1 as a whole, and in particular are stacked one on top of the other, in particular face-to-face and thus stacked in the axial direction.

[0034] The laminated core 3 has, for example, a rotor yoke (not visible in the figures), in particular one that is at least substantially annular, in which at least a longitudinal region of a rotor shaft 5 of the rotor 1 is arranged, extending in the axial direction of the rotor 1 and rotatable about the machine axis of rotation 2 relative to the stator. The laminated core 3 is thus arranged on the longitudinal region of the rotor shaft 5 and thus on the rotor shaft 5, wherein the laminated core 3 is connected in a rotationally fixed manner to the rotor shaft 5. In particular, the electric machine can provide torques for driving the motor vehicle via the rotor shaft 5 and thus via the rotor 1. In particular, the laminated core 3 is connected in a rotationally fixed manner to the rotor shaft 5, preferably via the rotor yoke, in particular such that the laminated core 3 is arranged on the longitudinal region and thus on the rotor shaft 5.Rotor teeth of the laminated core 3, which cannot be seen in the figures, are arranged on the rotor yoke, in particular in such a way that the rotor teeth protrude outwards from the rotor yoke in the radial direction of the laminated core 3 and thus of the rotor 1, the radial direction of which runs perpendicular to the axial direction and thus perpendicular to the machine rotation axis 2, wherein moreover the rotor teeth are spaced from one another in the circumferential direction of the rotor 1 and thus of the laminated core 3, which runs around the axial direction and thus around the machine rotation axis 2, and are arranged in particular so as to be evenly distributed, so that in the circumferential direction of the rotor 1 a respective rotor groove 6 of the laminated core 3, also referred to as a laminated core groove, is arranged between each two rotor teeth which are immediately adjacent in the circumferential direction of the rotor 1.The rotor windings 4 are wound around the rotor teeth, so that the rotor windings 4 run in the rotor slots 6 or run through them, in particular in the axial direction of the rotor 1 and thus of the laminated core 3. The rotor windings 4 form respective winding overhangs on end faces of the laminated core 3 that are opposite one another or facing away from one another in the axial direction of the rotor 1 and thus of the laminated core 3. These winding overhangs protrude from the respective axial end face of the laminated core 3 in the axial direction of the laminated core 3 and thus of the rotor 1, and thus protrude beyond the respective end face of the laminated core 3 in the axial direction of the rotor 1. One of the winding overhangs can be seen in Figs. 1 and 2 and is designated by 7, wherein the winding overhang 7 protrudes from a first of the axial end faces of the laminated core 3 in the axial direction of the rotor 1. The respective axial end face of the laminated core 3 is also referred to as the respective axial laminated core end face.For example, the first axial end face of the laminated core 3 is referred to as the A-side, or the first axial end face of the laminated core 3 is arranged on a so-called A-side of the rotor 1, wherein, for example, the second axial end face of the laminated core 3, facing away from the first axial end face of the laminated core 3 in the axial direction of the rotor 1, is also referred to as the B-side or is arranged on a so-called B-side of the rotor 1. The rotor 1 is described below with reference to the A-side, wherein the previous and following statements regarding the A-side can easily be transferred to the B-side and vice versa.

[0035] In conjunction with Fig. 2, it can be seen that a respective support device 8 is connected to the respective axial end face of the laminated core 3 in the axial direction of the rotor 1, wherein the support device connected to the first axial end face of the laminated core 3 and thus arranged on the A-side is explained in more detail below. Of course, the previous and following explanations regarding the support device 8 connected to the first axial end face of the laminated core 3 in the axial direction of the rotor 1 can also be easily transferred to the other support device 8, which is connected to the second axial end face of the laminated core 3 in the axial direction of the rotor 1.

[0036] The rotor teeth extend outward in the radial direction of the rotor 1 and thus of the laminated core 3, in particular away from the rotor yoke, wherein the axial direction of the rotor 1 and thus of the laminated core 3 is illustrated by a double arrow 21. The radial direction of the rotor 1 and thus of the laminated core 3 is illustrated by a double arrow 9. In the radial outward direction, a respective pole shoe 10 adjoins the respective rotor tooth, which is arranged at a respective outer or outermost end of the respective rotor tooth in the radial direction of the rotor 1.It can be seen that the respective pole shoe 10, viewed in the circumferential direction of the rotor 1, has a greater width or a greater extension than the respectively associated rotor tooth, wherein the circumferential direction of the rotor 1 and thus of the laminated core 3, running around the axial direction and thus around the machine rotation axis 2, is illustrated by a double arrow 11 and, for example, runs in a plane that is perpendicular to the axial direction (machine rotation axis 2). Furthermore, the respective rotor slot 6 is at least partially overlapped outwards in the radial direction of the laminated core 3 and thus of the rotor 1 by the respective pole shoe 10, so that the pole shoes 10 prevent the rotor windings 4 arranged between the rotor yoke and the pole shoe 10 from slipping off the rotor teeth when the rotor 1 rotates.Furthermore, the rotor 1 has the support devices 8, wherein the laminated core 3 is arranged between the support devices 8 in the axial direction of the rotor 1 and thus of the laminated core 3.

[0037] From Fig. 1 it can be seen that the respective support device 8 has a respective star disk 12 which - relative to the A-side - is arranged in the axial direction of the rotor 1 and thus of the laminated core 3 and the star disk 12 between the first axial end face of the laminated core 3 and the respective winding overhang 7. In particular, the star disk 12 ensures a deflection of the winding wires by which the rotor windings 4 are formed, in particular on the first axial end face. The respective support device 8 also comprises a respective support ring 13. As will be explained in more detail below, the winding overhangs 7 are at least partially covered, i.e. overlapped, by the star disk 12 in the radial direction of the rotor 1. Furthermore, the star disk 12 is at least partially encased by the associated support ring 13.

[0038] The star disk 12 has a ring carrier 14 (Fig. 1), which is arranged in the axial direction of the rotor 1, in particular directly, on the rotor yoke, in particular rests. In particular, the ring carrier 14 rests in the axial direction of the rotor 1 directly on a first part of the first axial end face of the laminated core 3, wherein the first part of the first axial end face of the laminated core 3 is formed by the rotor yoke. The star disk 12 also has support teeth 15 projecting outward from the ring carrier 14 in the radial direction of the rotor 1 and thus of the star disk 12, wherein in particular one support tooth 15 is provided for each rotor tooth, in particular precisely. In other words, for example, a respective support tooth 15 of the star disk 12 is assigned to the respective rotor tooth, in particular precisely.The support teeth 15 are spaced apart from one another in the circumferential direction of the rotor 1 and thus of the star disk 12, which runs around the axial direction of the rotor 1 and thus of the star disk 12, and are arranged in particular so as to be evenly distributed, so that, in particular when viewed in the circumferential direction of the rotor 1 and thus of the star disk 12, between each two support teeth 15 that are immediately adjacent in the circumferential direction of the rotor 1, a respective groove of the star disk 12 is arranged, the respective groove of which is also referred to as the respective star disk groove and is arranged, for example, in extension of the respective rotor groove 6 and thus, for example, is part of the respective rotor groove 6 or extends the respective rotor groove 6, in particular in the axial direction of the rotor 1.The rotor windings 4 or the winding wires run through the respective rotor slot 6 and the respective adjoining star disk slot, so that on the first axial end face of the laminated core 3, the support teeth 15 are arranged in the axial direction of the rotor 1 between the winding overhangs 7 and the first axial end face of the laminated core 3. The support teeth 15 are arranged on the rotor teeth of the laminated core 3, which protrude radially from the rotor yoke and support the rotor windings 4, between the rotor teeth and the winding overhangs 7 of the rotor windings 4, such that the support teeth 15 bear directly against the first axial end face of the laminated core 3 in the axial direction of the rotor 1. In other words, the support teeth 15 bear directly against respective second parts of the first axial end face of the laminated core 3 in the axial direction of the rotor, wherein the second parts of the first axial end face of the laminated core 3 are formed by the respective rotor teeth.

[0039] Furthermore, the star disk 12 has roof regions 16, which protrude from the supporting teeth 15, in particular from the outermost or extreme ends of the supporting teeth 15, viewed in the radial direction of the star disk 12 and thus of the rotor 1, in the axial direction of the rotor 1 and thus of the star disk 12, and which are also referred to as end pieces. The roof regions 16 are arranged, in particular directly, on the pole pieces 10 of the laminated core 3 protruding from the rotor teeth. For example, the roof regions 16 are arranged directly on respective third parts of the first axial end face of the laminated core 3 in the axial direction of the rotor 1, wherein the third parts of the first axial end face of the laminated core 3 are formed by the pole pieces 10.Due to the roof regions 16, the winding heads 7 are at least partially, in particular at least predominantly and thus more than half or completely, overlapped and thus covered in relation to the A-side in the radial direction of the rotor 1 and thus of the star disk 12, so that the winding heads 7 can be or are supported outwardly in the radial direction of the rotor 1 and thus of the star disk 12, in particular directly, against centrifugal forces, on the roof regions 16. An axial end face 17 of the support ring 13, whose axial end face 17 is also referred to as the support ring end face or axial support ring end face, can be seen particularly clearly in Figs. 2 and 3. The support ring end face is an axial end surface of the support ring 13. It can be seen that the support ring end face faces away from the laminated core 3 in the axial direction of the rotor 1 and thus from the first axial end face of the laminated core 3.

[0040] In order to be able to realize a particularly advantageous cooling of the support ring 13 and thus of the rotor 1, the rotor 1 has an annular channel 18 arranged in the radial direction of the rotor 1 between the rotor shaft 5 and the support ring 13, which is delimited in the radial direction of the rotor 1 to the outside, in particular directly, by the support ring 13, in particular an inner circumferential surface M1 of the support ring 13.

[0041] 3 and 4 that the inner circumferential surface M1 of the support ring 13 is formed by an edge R of the support ring 13, also referred to as the annular channel edge or edge region, which edge R ends, for example, in the radial direction of the rotor 1 and thus of the rotor shaft 5, inwards at the edge R. Thus, the annular channel 18 is delimited outwards in the radial direction of the rotor 1 and thus of the rotor shaft 5, in particular directly, by the edge R of the support ring 13.

[0042] 3 and 4 also show that a channel 19, also referred to as a supply channel, runs within the rotor shaft 5 and can be flowed through by a lubricant and / or coolant, also simply referred to as a fluid. The rotor 1 or the electric machine preferably comprises the fluid, which is thus preferably a component of the rotor 1, in particular of the electric machine. The fluid is preferably a liquid, in particular an oil. As will be explained in more detail below, the channel 19 through which the fluid can flow opens, in particular directly, into the annular channel 18, so that the fluid flowing through the channel 19 can be introduced, in particular directly, into the annular channel 18.From the annular channel 18, the fluid introduced into the annular channel 18 and thus initially received in the annular channel 18 can flow to and along the end face 17 (support ring end face), whereby the fluid from the annular channel 18 can flow directly along the end face 17 and thus directly touches or can touch the end face 17. Thus, the end face 17 can be wetted with the fluid from the annular channel 18, so that the end face 17 and thus the support ring 13 and the rotor 1 as a whole can be cooled by means of the fluid from the annular channel 18.

[0043] In order to be able to supply the support ring end face particularly advantageously with the fluid from the annular channel 18, the inner circumferential surface M1 is convexly curved, viewed in a plane also referred to as the viewing plane, in which the axial direction of the rotor shaft 5 and thus of the rotor 1 and the machine rotational axis run. This is particularly clearly visible in Figs. 3 and 4. It can also be seen from Figs. 3 and 4 that the inner circumferential surface M1 has a first partial region T1 and a second partial region T2, which adjoins the first partial region T1 directly in the axial direction of the rotor shaft 5 and thus of the rotor 1 and towards the laminated core 3.The second partial region T2 is set back outwards in the radial direction of the rotor shaft 5 and the rotor 1 compared to the first partial region T1, so that the annular channel 18 in the second partial region T2 has a greater height or depth running in the radial direction of the rotor shaft 5 and thus of the rotor 1 than in the first partial region T1. Thus, for example, the fluid from the channel 19 can initially collect in the second partial region T2. ​​From the second partial region T2, the fluid can flow into the first partial region T1, from where the fluid can flow particularly advantageously to and along the support ring end face (end face 17). As a result, the support ring end face can be supplied with an advantageously large quantity of fluid, so that particularly good cooling can be achieved.In this case, the inner circumferential surface M1 is convex, at least in the first partial area T1, when viewed in the viewing plane, i.e. curved inwards in the radial direction of the rotor shaft 5 and thus towards the rotor shaft 5.

[0044] The channel 19 opens via at least or exactly one outlet opening 20, in particular directly, into the annular channel 18, in particular into the second partial region T2. ​​For example, the channel 19 opens via several outlet openings 20, in particular directly, into the annular channel 18, in particular into the second partial region T2. ​​Of these possibly provided several outlet openings of the channel 19, the outlet opening designated by 20 can be seen in Figs. 3 and 4. Viewed towards the annular channel 18, the channel 19 thus ends at the outlet opening 20.

[0045] To enable the fluid to particularly advantageously initially collect in the sub-region T2, it is provided that the outlet opening 20 is at least predominantly, in this case completely, overlapped by the second sub-region T2 in the radial direction of the rotor shaft 5 and thus of the rotor 1. Thus, the outlet opening 20 is not overlapped by the first sub-region T1 in the radial direction of the rotor shaft 5. As a result, the fluid flowing through the outlet opening 20 and thus flowing out of the channel 19 can be guided directly into the sub-region T2 and advantageously collect there, whereupon the fluid can flow into the sub-region T1 and via this to the end face 17.

[0046] In the first embodiment shown in Fig. 3, the channel 19 has a first length range L1, a second length range L2 and a third length range L3. The length ranges L1, L2 and L3 are fluidically connected to one another, so that the fluid flows through the length ranges L1, L2 and L3 on its way through the channel 19. In the flow direction of the fluid flowing through the channel 19 and towards the annular channel 18, the length range L2 is arranged downstream of the length range L1 and the length range L3 is arranged downstream of the length range L2 and thus downstream of the length range L1. Thus, on its way through the channel 19 and towards the annular channel 18, the fluid first flows through the length range L1, then through the length range L2 and then through the length range L3. It can be seen that the length range L3 has or forms the outlet opening 20 of the channel 19.In the present case, the first embodiment provides that the longitudinal regions L1 and L2 run perpendicularly or, in this case, obliquely to one another. This means that the fluid can flow through the longitudinal region L1 along a first flow direction and the longitudinal region L2 along a second flow direction, wherein the first flow direction and the second flow direction run perpendicularly or, in this case, obliquely to one another. The fluid can flow through the longitudinal region L3 along a third flow direction, wherein the third flow direction, so to speak, adjoins the second flow direction as an extension of the second flow direction. Thus, the longitudinal regions L2 and L3 are arranged, for example, parallel or coaxially to one another.In the present case, the second flow direction and thus also the third flow direction runs in the radial direction of the rotor shaft 5 and the rotor 1, so that the length region L2 and the length region L3 and also the outlet opening 20 can be flowed through by the fluid in the radial direction of the rotor shaft 5 and thus of the rotor 1.

[0047] In the first embodiment shown in Fig. 3, the rotor shaft 5 has a first shaft element 24 and a second shaft element 22. It is preferably provided that the shaft element 24, viewed on its own, is of one-piece design, i.e., is formed from a single piece. This means that the shaft element 24, viewed on its own, is a one-piece, i.e., one-part and thus made from a single piece, and thus integrally manufactured monoblock. Furthermore, it is provided in the first embodiment that the shaft element 22, viewed on its own, is of one-piece design, i.e., is formed from a single piece, and so the shaft element 22, viewed on its own, is preferably formed from a single piece. Thus, the shaft element 22 is preferably a one-piece, i.e., one-part and thus made from a single piece, and thus integrally manufactured monoblock.The shaft element 24 can be formed from a first material, and the shaft element 22 can be formed from a second material. In principle, it would be conceivable for the second material to correspond to the first material. Alternatively, it is conceivable for the second material to be a material different from the first material. For example, the first material is a metallic material. The second material can be a metallic material or a plastic, in particular an elastomer. For example, the shaft element 22 is designed as a sealing element. The second material can be elastically, in particular rubber-elastic, deformable, so that the shaft element 22 can be elastically, in particular rubber-elastic, deformable. For example, the second material is rubber. The shaft element 22 is formed separately from the shaft element 24, wherein in the present case the shaft element 22 is arranged on the shaft element 24.The shaft elements 21 and 22 are connected to one another in a rotationally fixed manner. It is provided that the outer circumferential surface M2, which directly bounds the annular channel 18 and at least the partial regions T1 and T2 in the radial direction of the rotor shaft 5, is formed at least predominantly, i.e., at least more than half, and in this case entirely, by the shaft element 22. Furthermore, it can be seen from Fig. 3 that the longitudinal regions L1 and L2 are formed in the shaft element 24 and thus run within the shaft element 24. The longitudinal regions L1 and L2 are formed, in particular, directly by a respective inner circumferential surface of the shaft element 24. The longitudinal region L3 and thus the outlet opening 20 are formed in the shaft element 22 and thus run within the shaft element 22.In particular, the length range L3 and thus the outlet opening 20 are limited, in particular directly, by an inner circumferential surface of the shaft element 22.

[0048] In the embodiment shown in Fig. 4, the rotor shaft 5 has at least one shaft element 23, which can be the shaft element 24, for example. Thus, for example, the previous and following statements regarding the shaft element 24 can easily be applied to the shaft element 23 and vice versa. A further shaft element which is formed separately from the shaft element 23, arranged on the shaft element 23 and connected to the shaft element 23 in a rotationally fixed manner and which forms the outer circumferential surface M2, is not provided in the second embodiment. Thus, in the second embodiment (Fig. 4), it is provided that the outer circumferential surface M2 is formed at least predominantly, in this case completely, by the shaft element 23.The longitudinal regions L1 and L2 of the channel 19 are formed in the shaft element 23 and thus run within the shaft element 23, in particular such that the longitudinal regions L1 and L2 are delimited, in particular directly, by a respective inner circumferential surface of the shaft element 23. The longitudinal region L2 comprises or forms the outlet opening 20. In the second embodiment, the longitudinal regions L1 and L2, i.e., the first flow direction and the second flow direction, run, for example, perpendicular to one another. The respective longitudinal region L1, L2, L3 and thus, for example, the outlet opening 20 can be a respective bore, thus being produced by machining.

[0049] List of reference symbols

[0050] 1 rotor

[0051] 2 machine rotation axes

[0052] 3 sheet packages

[0053] 4 rotor winding

[0054] 5 Rotor shaft

[0055] 6 Rotor groove

[0056] 7 winding head

[0057] 8 Support device

[0058] 9 Double arrow

[0059] 10 Pole piece

[0060] 11 Double arrow

[0061] 12 star disc

[0062] 13 Support ring

[0063] 14 ring bearers

[0064] 15 supporting tooth

[0065] 16 roof area

[0066] 17 axial front side

[0067] 18 Ring Canal

[0068] 19 Channel

[0069] 20 Exit opening

[0070] 21 Double arrow

[0071] 22 second shaft element

[0072] 23 Shaft element

[0073] 24 first wave element,

[0074] L1 first length range

[0075] L2 second length range

[0076] L3 third length range

[0077] M1 inner circumferential surface

[0078] M2 outer peripheral surface

[0079] R edge

Claims

Patent claims 1. A rotor (1) for an electric machine of a motor vehicle, comprising a rotor shaft (5), a laminated core (3) arranged on the rotor shaft (5) and connected to the rotor shaft (5) in a rotationally fixed manner, at least one star disk (12) arranged on an axial end face of the laminated core (3), by means of which star disk, winding heads (7) of rotor windings (4) of the rotor (1) carried by the laminated core (3) and projecting axially from the end face, are at least partially covered outwards in the radial direction (9) of the rotor (1), and a support ring (13) by means of which the star disk (12) is at least partially encased, characterized by an annular channel (18) arranged in the radial direction (9) of the rotor (1) between the rotor shaft (5) and the support ring (13), into which at least one channel (19) runs in the rotor shaft (5) and through which a lubricant and / or coolant can flow.

2. Rotor (1) according to claim 1, characterized in that the annular channel (18) is delimited in the radial direction of the rotor shaft (5) towards the outside directly by an inner circumferential surface (M1) of the support ring (13).

3. Rotor (1) according to claim 2, characterized in that the inner circumferential surface (M1) is convexly curved when viewed in a plane in which the axial direction (21) of the rotor shaft (5) runs.

4. Rotor (1) according to claim 2 or 3, characterized in that the inner circumferential surface (M1) has a first partial area (T1) and a second partial area (T2) which adjoins the first partial area (T1) directly in the axial direction (21) of the rotor shaft (5) and towards the laminated core (3), and which is set back outwards in the radial direction (9) of the rotor shaft (5) relative to the first partial area (T1).

5. Rotor (1) according to claim 4, characterized in that the inner circumferential surface (M1) is convexly curved at least in the first partial region (T1) when viewed in a plane in which the axial direction (21) of the rotor shaft (5) runs.

6. Rotor (1) according to one of the preceding claims, characterized in that the channel (19) opens into the annular channel (18) via at least one outlet opening (20) of the channel (19).

7. Rotor (1) according to claim 6 in its dependent claim 4 or 5, characterized in that the outlet opening (20) is at least predominantly overlapped outwards in the radial direction (9) of the rotor shaft (5) by the second partial region (T2).

8. Rotor (1) according to one of the preceding claims, characterized in that the annular channel (18) is delimited in the radial direction (9) of the rotor shaft (5) inwards directly by an outer circumferential surface (M2) of the rotor shaft (5).

9. Rotor (1) according to claim 8, characterized in that the rotor shaft (5) has a first shaft element (24), in which at least a first longitudinal region (L1, L2)) of the channel runs, and a second shaft element (22) which is formed separately from the first shaft element (24), is arranged on the first shaft element (24) and is connected in a rotationally fixed manner to the first shaft element (24), in which a second longitudinal region (L3) of the channel (19) runs, which is fluidically connected to the first longitudinal region (L1, L2), wherein the outer peripheral surface (M2) is formed by the second shaft element (22).

10. Electrical machine for a motor vehicle, with a stator and with a rotor (1) according to one of the preceding claims.

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