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

Abstract

The invention relates to a rotor (1) for an electrical machine, having a rotor shaft (5), having a laminated core (3) that is arranged on the rotor shaft (5) and connected to the rotor shaft (5) for conjoint rotation, having a star disc (12) that is arranged on an axial end face of the laminated core (3) and at least partially outwardly covers winding heads (7), which protrude axially from the end face, of rotor windings (4) in the radial direction (9) of the rotor (1), and having a support ring (13) that at least partially encases the star disc (12), wherein provision is made for an annular channel (18) that is arranged between the rotor shaft (5) and the support ring (13) in the radial direction (9) of the rotor (1) and into which at least one channel (19) that is able to channel a lubricant and / or coolant and that runs in the rotor shaft (5) opens, and wherein the annular channel (18) is non-round when viewed in a plane running perpendicular to the axial direction (7) of the rotor (1).

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] The annular channel is non-circular when viewed in a plane perpendicular to the axial direction of the rotor, as a result of which the rotor, viewed in said plane, has a shape other than a circle. For this purpose, it is provided in particular that the inner circumferential surface of the support ring, viewed in said plane, is non-circular, i.e., has a shape other than a circle. Alternatively or additionally, the outer circumferential surface can be non-circular when viewed in the plane, thus having a shape other than circular, or the outer circumferential surface of the rotor shaft can be circular when viewed in the plane.

[0013] 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.

[0014] 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.Due to the non-circular design of the annular channel, the lubricant and / or coolant from the annular channel can be distributed particularly advantageously, in particular at least substantially evenly, on the support ring end face, particularly during rotation of the rotor, so that the support ring end face can be supplied with the lubricant and / or coolant from the annular channel over a particularly large area.

[0015] 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. For example, if the annular channel were circular when viewed in the plane and thus circular in shape, this could potentially result in a very uneven supply of lubricant and / or coolant from the annular channel to the support ring face, which can now be avoided by the invention.In other words, the invention enables at least substantially uniform wetting of the support ring end face, also referred to as the end face or designed as the end face, with the lubricant and / or coolant from the annular channel, so that particularly advantageous heat dissipation from the rotor can be ensured.In order to be able to achieve particularly advantageous, in particular at least substantially uniform, wetting of the support ring end face with the lubricant and / or coolant from the annular channel, one embodiment of the invention provides that the annular channel and thus, for example, the inner circumferential surface, due to their respective non-circular shapes, have at least a first longitudinal region which, in the circumferential direction, is set back outwards in the radial direction of the rotor relative to second longitudinal regions of the annular channel and thus the inner circumferential surface, which second longitudinal regions directly adjoin the first longitudinal region on both sides in the circumferential direction, in particular viewed in the plane. For example, the first longitudinal region is arcuate, in particular viewed in the plane. It is conceivable that the respective second longitudinal region is straight and thus rectilinear, or arcuate, in particular viewed in the plane.In particular, for example, the first length range is concave, i.e., concavely curved, particularly viewed in the plane. For example, the respective second length range is concave, i.e., concavely curved, particularly viewed in the plane.

[0016] It has proven particularly advantageous if the channel, in particular with respect to the first length range and the second length ranges exclusively, opens into the first length range, so that, for example, the channel does not open into one of the second length ranges. As a result, the lubricant and / or coolant flowing out of the channel can be supplied to the support ring end face via the annular channel in a particularly advantageous manner, in particular in such a way that the support ring end face can be wetted particularly advantageously, in particular at least substantially uniformly, with the lubricant and / or coolant.

[0017] Since the first length range, particularly viewed in the plane, is set back outwards in the radial direction of the rotor compared to the second length ranges, the first length range is a so-called out-of-roundness, by means of which, for example, the actual non-circular shape of the annular channel and thus, for example, of the inner circumferential surface is formed.

[0018] The inner circumferential surface is, for example, an edge or edge region of the support ring, also referred to as the annular channel edge, which ends inwardly at the edge, in particular in the radial direction of the rotor. The annular channel is delimited outwardly in the radial direction of the rotor, in particular directly, by the edge of the support ring. Thus, the edge of the support ring is preferably non-circular when viewed in the plane, as a result of which the annular channel is non-circular when viewed in the plane. Thus, the first length region and the second length region are length regions of the edge of the support ring. The aforementioned non-circularity of the annular channel is therefore a non-circularity of the edge.This radial out-of-roundness allows, for example, a flow rate of the lubricant and / or coolant, also referred to as the flow rate, to be adjusted as needed in the circumferential direction running around the axial direction of the rotor, so that a wetting surface of the support ring, whose wetting surface is wettable or is wetted with the lubricant and / or coolant from the channel, can be adjusted as needed, i.e., adjusted. A first distance running in the radial direction of the rotor, by which the first length range, and thus the radial out-of-roundness, is set back outwards relative to the second length ranges, is also referred to as the depth of the first length range, and thus the depth of the radial out-of-roundness.A second extension of the first length range, i.e., the radial out-of-roundness, running in the circumferential direction of the rotor, is also referred to as the width of the first length range, i.e., the width of the out-of-roundness. By adjusting the depth and width of the out-of-roundness, i.e., by appropriately designing or adjusting the depth and width of the out-of-roundness, the distribution of the lubricant and / or coolant from the annular channel can be adjusted or adjusted as needed, so that, for example, the distribution of the lubricant and / or coolant from the annular channel on the support ring face can be adjusted to a desired wetting distribution. This allows for particularly advantageous cooling of the support ring face.

[0019] In order to be able to wet the support ring end face with the lubricant and / or coolant over a particularly large area and thus in a particularly advantageous and required manner, a further embodiment of the invention provides that the annular channel and thus in particular the inner circumferential surface of the support ring, thus the edge of the support ring, has a plurality of first length regions due to its non-circular shape, wherein the respective first length region is set back outwards in the radial direction of the rotor compared to the respective second length regions of the annular channel and thus the inner circumferential surface, thus the edge of the support ring, which second length regions directly adjoin the respective first length region on both sides in the circumferential direction.The previous and following statements regarding the first length range mentioned above can also be readily applied to the plurality of first length ranges, and the previous and following statements regarding the second length ranges mentioned above can also be readily applied to the second length ranges mentioned thereafter, and vice versa. Preferably, the number of first length ranges is at least or exactly two. Preferably, the number of first length ranges is greater than two. Thus, for example, the number of second length ranges is at least or exactly two, in particular greater than two.

[0020] For example, the number of second length ranges corresponds to the number of first length ranges. For example, the first length ranges are evenly distributed in the circumferential direction of the rotor, viewed around the axial direction of the rotor. Alternatively or additionally, the second length ranges are preferably evenly distributed in the circumferential direction of the rotor. This allows for a particularly advantageous and needs-based supply and thus wetting of the support ring face with the lubricant and / or coolant from the annular channel.

[0021] A further embodiment is characterized in that the channel, in particular with respect to the first length regions and the second length regions, opens exclusively into the first length regions, whereby the support ring end face can be wetted particularly advantageously and in particular over a particularly large area with the lubricant and / or coolant from the ring channel.

[0022] It has proven particularly advantageous if the respective first longitudinal region is assigned precisely one respective outlet opening of the channel, which opens via its respective outlet opening, in particular directly, into the respective first longitudinal region to which the respective outlet opening is assigned. Thus, the lubricant and / or coolant flowing through the channel can flow through the respective outlet opening and thus flow out of the channel and thereby flow, in particular directly, into the respective first longitudinal region, whereby a particularly advantageous and in particular at least substantially uniform and / or extensive wetting of the support ring end face with the lubricant and / or coolant from the annular channel can be achieved.

[0023] Preferably, the outlet openings of the channel are evenly distributed in the circumferential direction of the rotor.

[0024] 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.

[0025] A further embodiment is characterized in that the outlet opening is circular, particularly when viewed in a plane perpendicular to the radial direction of the rotor. This ensures a particularly advantageous supply of the lubricant and / or coolant to the annular channel and thus to the support ring face.

[0026] It has therefore proven particularly advantageous if the outlet opening is designed as a slot whose longitudinal extension runs in the circumferential direction of the rotor. This allows the annular channel, and through it the support ring face, to be filled with an advantageous, particularly advantageously large, amount of lubricant and / or coolant as needed, thus ensuring particularly advantageous wetting of the support ring face with the lubricant and / or coolant and thus particularly advantageous cooling of the rotor.

[0027] Finally, it has proven particularly advantageous if the edge of the support ring facing inwards in the radial direction of the rotor and towards the rotor shaft, in particular the outer circumferential surface of the rotor shaft, through whose edge the annular channel is directly delimited outwards in the radial direction of the rotor, is convexly curved, in particular when viewed in a sectional plane in which the machine axis of rotation and thus the axial direction of the rotor runs. As a result, the lubricant and / or coolant introduced into the annular channel via the channel and thus initially received in the annular channel can flow particularly advantageously along the convex edge of the support ring, also referred to as the edge region, and then flow, in particular directly, along the end face of the support ring, thereby achieving particularly advantageous cooling.

[0028] 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.

[0029] Further details of the invention will become apparent from the following description of preferred embodiments with the accompanying drawings. In the drawings:

[0030] Fig. 1 shows a partial schematic perspective view of a rotor of an electric machine for a motor vehicle;

[0031] Fig. 2 shows a schematic and partially sectioned

[0032] Perspective view of the rotor;

[0033] Fig. 3 shows a further schematic and partially sectioned

[0034] Perspective view of the rotor;

[0035] Fig. 4 shows a partial schematic and perspective front view of a first embodiment of the rotor; and

[0036] Fig. 5 shows a partial schematic and perspective front view of a second embodiment of the rotor.

[0037] In the figures, identical or functionally identical elements are provided with the same reference symbols.

[0038] 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.

[0039] 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 in such a way 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.

[0040] 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.

[0041] 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.

[0042] 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.

[0043] 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.

[0044] 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.By means of 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 on the roof regions 16, in particular directly, in the radial direction of the rotor 1 and thus of the star disk 12, towards the outside, in particular against centrifugal forces.

[0045] An axial end face 17 of the support ring 13 can be seen particularly well in Fig. 2 and 3, the axial end face 17 of which is also referred to as the support ring end face or axial support ring end face. 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 away from the first axial end face of the laminated core 3. In order to be able to realize 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 outwards in the radial direction of the rotor 1, in particular directly, by the support ring 14, in particular an inner circumferential surface M1 of the support ring 13.In the radial direction inwards of the rotor 1, the annular channel 18 is delimited, in particular directly, by the rotor shaft 5, in particular by an outer circumferential surface M2 of the rotor shaft 5. From Fig. 3 it can be seen 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 ends inwards in the radial direction of the rotor 1 at the edge R. Thus, the annular channel 18 is delimited outwards in the radial direction of the rotor 1, in particular directly, by the edge R of the support ring 13.

[0046] Fig. 4 shows a first embodiment of the rotor 1 in a schematic and perspective front view.

[0047] From Fig. 2, it can be seen that a channel 19, also referred to as a supply channel, runs within the rotor shaft 5, through which a lubricant and / or coolant, also simply referred to as a fluid, can flow. Preferably, the rotor 1 or the electric machine contains 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.

[0048] From Fig. 2 to 4 it can be seen that, 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), wherein 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. The end face 17 can thus be wetted with the fluid from the annular channel 18, so that the end face 17 can be cooled by means of the fluid from the annular channel 18.

[0049] In order to be able to wet the end face 17 particularly advantageously, in particular over a particularly large area and / or at least uniformly, with the fluid from the annular channel 18, it is provided that, as can be seen from Figs. 4 and 5, the edge R and thus the inner circumferential surface M1 and thus the annular channel 18 is non-circular when viewed in a plane running perpendicular to the axial direction of the rotor 1 and thus perpendicular to the machine rotation axis 2, and thus has a shape different from a circular shape. For example, the outer circumferential surface M2 of the rotor shaft 5, which directly borders the annular channel 18 in the radial direction of the rotor 1, is round, i.e. circular, when viewed in the plane.

[0050] Due to their respective non-circular shape, the edge R and thus the annular channel 18 have a plurality of first length regions L1, wherein the respective first length region L1 is set back outwards in the radial direction of the rotor 1 compared to respective second length regions L2 of the edge R and thus of the annular channel 18, which second length regions L2 directly adjoin the respective first length region L1 on both sides in the circumferential direction of the rotor 1. For example, a number of the first length regions L1 corresponds to a number of the second length regions L2. For example, the first length regions L1 are arranged so as to be evenly distributed in the circumferential direction of the rotor 1 and, for example, the second length regions L2 are arranged so as to be evenly distributed in the circumferential direction of the rotor 1.

[0051] From Fig. 4 and 5 it can be seen that the channel 19, with respect to the first length ranges L1 and the second length ranges L2, opens exclusively into the first length ranges L1, in this case such that exactly one respective outlet opening 20 of the channel 19 is assigned to the respective first length range L1. The channel 19 opens via its respective outlet opening 20 directly into the respective first length range L1, to which the respective outlet opening 20 is assigned. The respective outlet opening 20 can be flowed through by the fluid, for example in the radial direction of the rotor 1, so that the fluid flowing through the respective outlet opening 20 in the radial direction of the rotor 1 can be introduced directly into the annular channel 18 in the radial direction of the rotor 1.

[0052] In the first embodiment shown in Fig. 4, the respective outlet opening 20 is formed as a respective slot, the respective longitudinal extension direction of which runs in the circumferential direction of the rotor 1.

[0053] In the second embodiment shown in Fig. 5, the respective outlet opening 20 is circular and thus circular in shape. In particular, it is provided that the respective outlet opening 20 is at least partially, in particular at least predominantly and thus more than half or completely, overlapped by the edge R of the support ring 13 in the radial direction of the rotor 1, whereby the end face 17 of the support ring 13 can be particularly advantageously supplied with the fluid and thus wetted via the annular channel 18.

[0054] The respective first length range L1 is also referred to as out-of-roundness or radial out-of-roundness. In both the first and second embodiments, exactly one outlet opening 20 is provided for each out-of-roundness. Alternatively, it is conceivable that two or more outlet openings 20 of the channel 19 are provided for each out-of-roundness.

[0055] It may be desirable for a quantity of fluid, which is introduced, i.e. injected, into the rotor shaft 5 and thus into the channel 19, for example, from exactly one side, to be distributed as evenly as possible between the A side and the B side, i.e. between the end faces of the support rings 13 facing away from the laminated core 3 in the axial direction. For this purpose, it is conceivable, for example, that a first number of outlet openings 20 on the A side and a second number of outlet openings 20 on the B side differ from one another, for example such that the second number is twice as large as the first number. For example, the second number can be 6, wherein the first number is, for example, 3. For example, the outlet openings 20 are arranged so as to be evenly distributed in the circumferential direction of the rotor 1.For example, by having two or more radial out-of-roundnesses per outlet opening 20 of the channel 19 (for example, six or more out-of-roundnesses with, for example, three outlet openings 20), six or more radial wetting areas can be created on the A-side for the support ring end face there, even though the fluid only exits radially at three locations, for example. With a sufficient cross-section of the annular channel 18, which is designed, for example, as an oil ring channel or also referred to as an oil ring channel, the number of outlet openings 20 formed in the rotor shaft 5 and penetrate it, in particular completely, can be reduced accordingly.

[0056] It is particularly clearly evident from Fig. 3 that the edge R and thus the inner circumferential surface M1, particularly viewed in a sectional plane in which the machine rotational axis 2 runs, is convexly curved, thus curved toward the rotor shaft 5 and is thereby particularly circular.

[0057] 1 rotor

[0058] 2 machine rotation axes

[0059] 3 sheet package

[0060] 4 rotor windings

[0061] 5 Rotor shaft

[0062] 6 Rotor groove

[0063] 7 winding head

[0064] 8 Support device

[0065] 9 Double arrow

[0066] 10 Pole piece

[0067] 11 Double arrow

[0068] 12 star disc

[0069] 13 Support ring

[0070] 14 ring bearers

[0071] 15 supporting tooth

[0072] 16 roof area

[0073] 17 axial front side

[0074] 18 Ring Canal

[0075] 19 Channel

[0076] 20 Exit opening

[0077] 21 Double arrow

[0078] L1 first length range

[0079] L2 second length range

[0080] M1 inner circumferential surface

[0081] M2 outer peripheral surface

[0082] 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 which winding heads (7) of rotor windings (4) of the rotor (1) supported by the laminated core (3) 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 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,wherein the annular channel (18) is non-circular when viewed in a plane perpendicular to the axial direction (7) of the rotor (1).

2. Rotor (1) according to claim 1, characterized in that the annular channel (18) has, due to its non-circular shape, at least a first longitudinal region (L1) which is set back outwards in the radial direction (9) compared to second longitudinal regions of the annular channel (18) which directly adjoin the first longitudinal region (L1) on both sides in the circumferential direction (11).

3. Rotor (1) according to claim 2, characterized in that the channel (19) opens into the first longitudinal region (L1).

4. Rotor (1) according to claim 1, characterized in that the annular channel (18) has a plurality of first length regions (L1) due to its non-circular shape, wherein the respective first length region (L1) is spaced apart from respective in the circumferential direction (11) to the respective, first length region (L1) directly adjoining on both sides, second length regions (L2) of the annular channel (18) is set back outwards in the radial direction (9).

5. Rotor (1) according to claim 4, characterized in that the channel (19) opens into the first longitudinal regions (L1).

6. Rotor (1) according to claim 5, characterized in that the respective first length region (L1) is assigned exactly one respective outlet opening (20) of the channel (19), which opens via its respective outlet opening (20) into the respective first length region (L1) to which the respective outlet opening (20) is assigned.

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

8. Rotor (1) according to claim 6 or 7, characterized in that the outlet opening (20) is circular or designed as a slot whose longitudinal extension direction runs in the circumferential direction (11) of the rotor (1).

9. Rotor (1) according to one of the preceding claims, characterized in that an edge (R) of the support ring (13) pointing inwards in the radial direction (9) of the rotor (1) and facing the rotor shaft (5), by whose edge (R) the annular channel (18) is directly delimited outwards in the radial direction (9), is convexly curved.

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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