Electric machine, component for an electric machine and motor vehicle comprising an electric machine

Abstract

An electrical machine comprising at least one component (3) forming either a stator (4) or a rotor (5), which component has at least two teeth (15) each extending along a radial direction (12) of the electrical machine (2), each having a winding (16) wound around said teeth, wherein at least one of the windings (16) comprises a plurality of winding layer groups (27) arranged one above the other with respect to the radial direction (12), wherein each of the winding layer groups (27) comprises one or more winding layers (28) arranged one above the other, wherein the winding layer groups (27) are each formed from a separate and electrically conductive conductor wire (20), wherein the electrical machine (2) has a cooling system (21) by means of which a cooling fluid can be guided through a hollow cross-section of at least two conductor wires (20) in such a way that at least two of the winding layer groups (27) are fluidically connected in parallel.

Description

[0001] The present invention relates to an electric machine. The present invention further relates to a component for an electric machine. Furthermore, the present invention relates to a motor vehicle comprising an electric machine.

[0002] In relation to the housing of an electrical machine, this typically comprises a fixed stator or stator and a rotor or rotor mounted so as to be rotatable about a rotational axis. If the electrical machine is designed as an internal rotor, the rotor is arranged in a region radially further inward than the stator with respect to its rotational axis. If the electrical machine is designed as an external rotor, the rotor is arranged in a region radially further outward than the stator with respect to this rotational axis.

[0003] To operate an electric machine, its windings are energized by an electric current, which causes the windings to heat up. Consequently, cooling of the windings is necessary, for which purpose a cooling fluid is passed, for example, through a rotor shaft or through a rotor core. Corresponding systems are known from DE 20 2012 007 645 U1 or WO 2020 / 049 830 A1. However, such cooling concepts, in particular so-called rotor shaft cooling, are disadvantageous because the cooling effect only occurs indirectly. This means that the heat is not transferred directly to the cooling fluid at its point of origin, i.e., in the area of ​​the windings, but instead must first be transferred from the winding to the rotor shaft or to the rotor core, which weakens the cooling effect.To counteract this, it is known from the prior art to direct the cooling fluid through the conductor wires designed as waveguides for direct cooling of the windings. Corresponding systems are known, for example, from DE 10 2020 114 683 A1, DE 10 2013 205 506 A1, DE 10 2017 119 033 A1, WO 2017 / 055 246 A2, WO 2015 / 150 556 A1, DE 10 2013 205 506 A1, or US Pat. No. 3,821,569 A.

[0004] Further concepts regarding the cooling of the windings of electrical machines by means of a cooling liquid are known from US 2013 / 0 285 487 A1, US 3 652 882 A and US 4 360 750 A.

[0005] It is the object of the present invention to provide an improved concept for an electrical machine with a conductor wire which forms a winding and through whose hollow cross-section a cooling fluid can be guided.

[0006] According to the invention, the object is achieved in an electrical machine of the type mentioned at the outset in that the machine comprises at least one component forming either a stator or a rotor, which component has at least two teeth each extending along a radial direction of the electrical machine, each with a winding wound around said teeth, wherein at least one of the windings has a plurality of winding layer groups arranged one above the other with respect to the radial direction, wherein each of the winding layer groups comprises one or more winding layers arranged one above the other, wherein the winding layer groups are each formed from a separate and electrically conductive conductor wire, wherein the electrical machine has a cooling system by means of which a cooling fluid can be guided through a hollow cross section of at least two conductor wires in such a way that at least two of the winding layer groups are fluidically connected in parallel.

[0007] The electric motor can preferably generate a traction torque that can be transmitted to the wheels of a motor vehicle via a drive train. The present invention is based on the idea that the cooling fluid flow supplied to the winding is divided into several partial flows that are fed to different winding layer groups. The partial flows do not flow through the entire winding, but only a portion of it, namely the respective winding layer group, thereby increasing the cooling effect. The cooling fluid is preferably a gas, in particular air, or, more preferably, a cooling liquid, in particular water or oil.

[0008] According to the invention, at least one of the windings comprises a plurality of winding layer groups arranged one above the other in the radial direction. Each of the winding layer groups comprises one winding layer or a plurality of winding layers arranged one above the other, wherein the winding layer groups are each formed from a separate conductor wire. The winding thus comprises a plurality of conductor wires, wherein these conductor wires or the winding layer groups can be electrically connected in series with one another. In this embodiment, the respective winding is formed from a conductor that is interrupted with respect to its longitudinal direction, wherein the sections of this conductor are formed from the separate conductor wires.

[0009] Each of the winding layers extends along the entire circumference of the respective tooth or completely surrounds it laterally. The winding layer comprises at least one winding circuit of the conductor wire, which surrounds or completely surrounds the tooth by 360° or exactly once. If the winding layer has multiple winding circuits, then this can have a spiral structure, viewed in the radial direction, that is perpendicular to the radial direction. In this case, the winding circuits within a winding layer are arranged concentrically around the respective tooth.

[0010] Below, definitions of relevant spatial directions for the electrical machine according to the invention are introduced. A rotor shaft of the rotor is mounted for rotation about a rotation axis that extends along a longitudinal direction of the electrical machine. The radial direction extends perpendicular to the longitudinal direction. A circumferential direction, in turn, is perpendicular to the radial direction. This means that a point rotating about the rotation axis moves along the circumferential direction. If one of these directions is mentioned without specific reference, it refers to the electrical machine according to the definitions just introduced. The longitudinal, radial, and circumferential directions with respect to the component correspond to the longitudinal, radial, and circumferential directions of the electrical machine.

[0011] The conductor wire forming a winding layer group can have an input-side end section and / or an output-side end section. The end sections can comprise the front ends or end faces of the respective conductor wire, so that the inlet opening of the cooling channel is arranged in the region of the input-side end section and / or the outlet opening of the cooling channel is arranged in the region of the output-side end section. The input-side end section and / or the output-side end section can protrude laterally from the winding relative to the longitudinal direction of the respective tooth or winding in order to facilitate or enable fluidic and / or electrical contact with this winding.

[0012] According to the invention, the tooth, or at least a portion of the tooth, extends along the radial direction. The winding laterally surrounds the respective tooth, relative to the radial direction or the longitudinal direction of the tooth. Accordingly, a longitudinal direction of the conductor wire or the winding extends at least largely perpendicular to the radial direction.

[0013] The conductor wire forming the winding has a hollow cross-section. This means that the conductor wire has a cooling channel inside it that extends along the longitudinal direction of the conductor wire and is closed at the sides. The longitudinal direction of the conductor wire and the longitudinal direction of the cooling channel are identical. Preferably, the conductor wire has an opening at each of its ends, i.e., at its end faces, which each form an inlet or outlet opening of the cooling channel. The cooling fluid can be supplied to the conductor wire through one of these openings and discharged through the other opening.

[0014] The conductor wire is electrically conductive and therefore consists of an electrically conductive material, such as a metal like copper. The outer cross-section of the conductor wire can be round, particularly elliptical or circular, or rectangular, particularly with rounded corners. The same applies to its inner cross-section, which forms the outer cross-section of the cooling channel.

[0015] The electrical machine according to the invention is preferably designed as a salient-pole synchronous machine. Salient-pole synchronous machines are synchronous machines, usually DC-excited, in which windings are energized to generate the DC excitation field. In contrast to solid-pole machines, in which the rotor or armature has longitudinal slots in which the windings are accommodated, salient-pole synchronous machines have teeth on the stator or rotor that form pole shoes, around which the windings are wound. Salient-pole synchronous machines are often implemented as internal rotors. If, in this case, the salient-pole synchronous machine is implemented as an external-pole salient-pole machine, the teeth are arranged on the stator. In a salient-pole synchronous machine implemented as an internal-pole salient-pole machine, the teeth are arranged on the rotor.Preferably, the electrical machine according to the invention is designed as an internal rotor in which the component is the rotor, so that the electrical machine is an internal pole salient pole machine.

[0016] It is conceivable that the electrical machine according to the invention has one or more fluidic input connection components, by means of which the respective input-side end sections of the conductor wires of at least two winding layer groups are fluidically connected to one or more supply chambers, which are fluidically connected upstream of these conductor wires, in such a way that these winding layer groups are fluidically connected in parallel. The cooling fluid flow flowing through the supply chamber is divided at the fluidic input connection component into several sub-streams, which are supplied to different winding layer groups accordingly. The fluidic input connection component can be made of a plastic or a metal.

[0017] One or more fluidic output connection components can be provided, by means of which the respective output-side end sections of the conductor wires of at least two winding layer groups are fluidically connected to one or more discharge chambers, which are fluidically connected downstream of these conductor wires. After flowing through the respective winding layer group, the cooling fluid is fed to the discharge chamber via the output-side end section and the fluidic output connection component. The partial flows flowing through the respective winding layer groups combine in the respective fluidic output connection component. The fluidic output connection component can be made of a plastic or a metal.

[0018] The electrical machine according to the invention can have one or more supply parts, each of which is or are arranged next to at least one of the windings with respect to a longitudinal direction of the electrical machine, wherein the or at least one of the plurality of supply parts is designed as a feed part and has the or at least one of the plurality of feed chambers, or wherein the or at least one of the plurality of supply parts is designed as a discharge part and has the or at least one of the plurality of discharge chambers. The supply part can be a component made of a metal or a plastic.

[0019] It is conceivable that the or at least one of the plurality of supply parts is formed in a ring shape and is arranged concentrically around the or a rotor shaft extending along the longitudinal direction and rotatably mounted of the component forming the rotor, wherein the or at least one of the plurality of supply chambers and / or the or at least one of the plurality of discharge chambers is formed in a ring shape and is arranged concentrically around the rotor shaft. The supply part can be fastened to the component, in particular the rotor shaft and / or the teeth. It is conceivable that the supply chamber is fluidically connected upstream of all winding layer groups of all windings and / or that the discharge chamber is fluidically connected downstream of all winding layer groups of all windings.

[0020] It is conceivable that the or at least one of the plurality of fluidic input connection components and / or the or at least one of the plurality of fluidic output connection components is attached to the supply part. It is conceivable that the supply part has at least one receiving opening that opens into the supply chamber or the discharge chamber, with the connection component being inserted into the receiving opening. Preferably, both the supply part and the discharge part are provided, with the respective winding being arranged therebetween, relative to the longitudinal direction.

[0021] The electrical machine preferably has one or more electrical connecting components, each of which connects end sections of the conductor wires of two adjacent winding layer groups of one of the windings to one another, so that these winding layer groups are electrically connected in series. Although the winding in this embodiment does not have a single continuous conductor wire, but rather several conductor wires, at least the conductor wires of the winding layer groups connected by means of the electrical connecting component form an electromagnetic field coil due to their electrical series connection. The advantage here is that to produce the winding, not a single, continuous or uninterrupted piece of conductor wire needs to be wound around the tooth, but rather only shorter pieces of conductor wire need to be positioned accordingly.The electrical connection component can be made of an electrically conductive material, such as a metal such as copper. The electrical connection component can be made of an electrically insulating material, such as a plastic, and can have an electrically conductive connecting element by means of which the electrical contact between the respective end sections is realized.

[0022] It is particularly preferably provided that the end sections of the conductor wires of all pairwise adjacent winding layer groups of the respective winding are connected to one another via an electrical connection component, so that all winding layer groups of the respective winding are electrically connected in series one after the other.

[0023] Particularly preferably, at least one common connection component is provided, which forms the or one of the plurality of fluidic connection components and the or one of the plurality of electrical connection components. In this embodiment, the common connection component is provided as a common component that, on the one hand, realizes the electrical connection component or one of the electrical connection components and, on the other hand, the fluidic connection component or one of the fluidic connection components.

[0024] Preferably, the at least one common connecting component comprises a base body made of an electrically conductive material, which may be a metal such as copper, wherein the base body has at least one channel and / or at least one chamber through which the cooling fluid can be conducted. The channel or chamber is fluidically arranged between the supply or discharge chamber and the respective conductor wire. The respective end sections can be in touching contact with the electrically conductive base body, so that the electrical contact is established via the latter.

[0025] With regard to the cooling system, it can be provided that it forms a cooling circuit in which the cooling fluid can be conveyed by means of a conveying means. In this embodiment, the cooling fluid circulates from the conveying means to the windings and back again, thus being circulated accordingly. The conveying means can be a cooling fluid pump. A cooling device for cooling the cooling fluid, such as a heat exchanger, can be integrated into the cooling system.

[0026] The rotor shaft, or a rotor shaft of the component forming the rotor, extending along a longitudinal direction of the electric machine and rotatably mounted, can have or delimit at least one supply channel and / or at least one discharge channel, wherein the supply channel and / or the discharge channel extends at least partially along the longitudinal direction of the rotor shaft. The supply channel can lead from the conveying means to at least one of the conductor wires having the hollow cross-section. The discharge channel can lead from at least one of the conductor wires having the hollow cross-section to the conveying means. The supply channel and / or the discharge channel can be formed as a, in particular central, longitudinal bore in the rotor shaft.The supply channel and / or the discharge channel can have a hollow cylindrical or sleeve-like geometry and extend between the rotor shaft and a, in particular rotationally fixed, rotor shaft sleeve in which the rotor shaft is arranged or mounted.

[0027] The cooling circuit can comprise a movable section and a fixed section. In the movable section, the cooling fluid is guided through rotating components of the electric machine, in particular through the rotor. In the fixed section, the cooling fluid is guided through stationary components of the electric machine, in particular through the conveying means. For the cooling fluid to pass from the fixed to the movable section, it can be introduced into the supply channel by means of an introduction lance. For the cooling fluid to pass from the movable to the fixed section, it can flow through at least one transverse bore and / or lateral opening in the rotor shaft.

[0028] Particularly preferably, the component is assembled from multiple parts, with at least two of the parts each having at least one of the teeth. This embodiment is particularly advantageous for electrical machines designed as salient-pole synchronous machines. This makes it possible to implement the concept of conductor wires through which cooling fluid flows in salient-pole synchronous machines as well. For example, the windings in salient-pole synchronous machines are typically formed by winding the conductor wire around the tooth, for example using a winding needle. However, this requires sufficient elasticity of the conductor wire, since the adjacent arrangement of the teeth means there is only limited space available for guiding the winding needle. This causes the conductor wire to be bent so severely during the winding process that conductor wires with hollow cross-sections are fundamentally unsuitable for this purpose.For example, conductor wires with a hollow cross-sectional geometry typically have too high a mechanical stiffness, so that the flexibility required for winding using a winding needle is not provided.

[0029] This problem associated with the manufacture of salient-pole synchronous machines is overcome by the multi-part or multi-piece structure of the component. This multi-piece design enables the winding of the conductor wire around the tooth, particularly using the winding needle, before the component parts are assembled to form the final stator or rotor. Since the teeth are not yet in their final relative position in this state, a larger tool guidance area extending around the respective tooth is available for the winding needle. After the conductor wires have been wound around the tooth, the component parts can be joined or fastened together. Possible options for this include welding, soldering, screwing, riveting, and / or intermeshing toothing of the respective components.The parts may consist of iron, in particular laminated iron, wherein the joined parts preferably form a yoke.

[0030] In the electrical machine according to the invention, it can be provided that at least one of the parts, in particular each of the parts, is segment-like. With respect to the assembled state of the component, the segment-like part can be pie-shaped when viewed along the longitudinal direction, i.e., it can have two lateral outer sides that are at an angle to one another and that are in contact with the lateral outer sides of adjacent parts. The opening angle of the circular segment describing the part, i.e., the angle between its lateral outer sides, is preferably identical for all parts and is in particular 60°. In this case, the component is composed of six, preferably identically shaped or designed, parts. The lateral outer sides can converge to a point on the radial inside or be separated from one another by an inner outer side of the respective part.The lateral outer sides can be separated from each other radially on the outside by an outer outer side of the respective part. The inner outer side and / or the outer outer side can be circularly curved when viewed along the longitudinal direction.

[0031] In the electrical machine according to the invention, it can additionally or alternatively be provided that at least one of the parts, in particular each of the parts, has exactly one tooth. The tooth or, if the respective part has a plurality of teeth, the teeth can be arranged distributed on the outer side along the circumferential direction. Relative to the assembled state of the component and viewed along the longitudinal direction, the teeth can result in a star-like structure in which the teeth are arranged in particular equidistantly along the circumferential direction. If the opening angle of each of the parts is 60° and each of the parts also has exactly one tooth, the component comprises exactly six teeth. Receiving grooves through which the windings extend are formed between adjacent teeth.

[0032] If the component forms the rotor, it can be provided that the parts are arranged along a circumference of the rotor shaft or of a rotor shaft extending along the longitudinal direction of the electric machine and mounted for rotation. The parts are arranged next to one another along the circumferential direction. The inner outer side of the part can be in contact with the rotor shaft and in particular can be fastened thereto. The inner outer side of the part and a radial outer side of the rotor shaft can each have toothings that engage with one another or are toothed with one another. The longitudinal direction of the toothings preferably extends along the radial directions. A width direction of the toothings, along which their cross-sections remain the same, preferably extends along the longitudinal direction. The parts can thus be slipped onto the rotor shaft along the longitudinal direction for assembly.In addition to or as an alternative to the gearing, welded and / or soldered and / or screwed and / or riveted connections may be provided to fasten the parts to the rotor shaft.

[0033] The rotor shaft can be connected to the housing via at least one bearing, which is in particular a ball or roller bearing. The rotor shaft can be coupled to an input and / or output shaft of the electric machine or form such a shaft. Accordingly, a torque can be transmitted from the rotor shaft, in particular via the input and / or output shaft, to the drive train of the motor vehicle and / or vice versa.

[0034] Preferably, the teeth each have a T-shape with a longitudinal bar and a cross bar, the longitudinal bar extending along the radial direction, the conductor wire being wound around the longitudinal bar. With regard to the assembled state, it is preferably provided that the longitudinal direction of the longitudinal bar extends along the radial direction and the longitudinal direction of the cross bar extends along the circumferential direction. The cross bar can be curved radially on the outside, so that an air gap, in particular one with a constant width, is formed between this outer surface of the tooth and the stator or rotor. The tooth forms a pole piece, which effects a desired, in particular sinusoidal, field shape of the magnetic field generated by the winding towards the air gap.

[0035] The present invention further relates to a component for an electrical machine, designed as a stator or a rotor and having at least two teeth each extending along a radial direction of the component, each with a winding wound around it, wherein at least one of the windings has a plurality of winding layer groups arranged one above the other with respect to the radial direction, wherein each of the winding layer groups comprises one or more winding layers arranged one above the other, wherein the winding layer groups are each formed from a separate and electrically conductive conductor wire, wherein a cooling fluid of a cooling system of the electrical machine can be guided through a hollow cross section of at least two conductor wires in such a way that at least two of the winding layer groups are fluidically connected in parallel.All advantages and features explained in connection with the electrical machine according to the invention are equally transferable to the component according to the invention and vice versa.

[0036] The present invention further relates to a motor vehicle comprising an electric machine according to the above description. All advantages and features explained in connection with the electric machine according to the invention and the component according to the invention are equally applicable to the motor vehicle according to the invention and vice versa.

[0037] The electric machine can be connected to a drive train of the motor vehicle or be a component thereof, such that torque can be transmitted from the electric machine to wheels of the motor vehicle and / or vice versa. Specifically, the rotor or a rotor shaft of the rotor, which in particular forms an input and / or output shaft of the electric machine, can be coupled to a drive train of the motor vehicle, such that rotation of the rotor or the rotor shaft is transmitted to components of the drive train and vice versa. In addition to a drive shaft and the wheels, the drive train comprises further components that enable the transmission of torque between the electric machine and the wheels of the motor vehicle, such as a transmission and / or a clutch and / or a differential or the like. Details in this regard are well known to those skilled in the art and will not be explained in more detail here.

[0038] The electric machine can be operated in a drive mode in which it generates a traction torque to drive the motor vehicle. In this mode, the electrical energy stored in an electrical energy storage device of the motor vehicle is converted into kinetic energy of the motor vehicle by means of the electric machine. The accelerating or positive torque generated by the electric machine is transferred to the drive train and thus to the wheels. Specifically, the windings are electrically energized using the energy stored in the electrical energy storage device, which induces magnetic fields in the windings. These magnetic fields interact with the magnetic fields of other coils or permanent magnets of the electric machine in such a way that the rotation of the rotor and thus the positive torque is generated.

[0039] The electric machine can be operated in a recuperation mode in which it generates a deceleration torque to brake the motor vehicle. In this mode, the electric machine converts the kinetic energy of the motor vehicle into electrical energy, which can be stored in the motor vehicle's electrical energy storage device and / or used to operate the motor vehicle's electrical devices. The decelerating or negative torque present on the part of the rotor is transferred to the drive train and via this to the wheels. Specifically, the magnetic fields of additional coils or permanent magnets cause an electric current to be induced in the windings, with the corresponding electromagnetic interaction causing the negative torque and the current induced in the windings being usable, for example, to charge the electrical energy storage device.

[0040] Further advantages and features of the present invention will become apparent from the following exemplary embodiments and from the accompanying drawings. These schematically show: Fig. 1 a schematic diagram of a motor vehicle according to the invention according to an embodiment comprising an electric machine according to the invention according to an embodiment with a component according to the invention according to an embodiment, Fig. 2 a longitudinal section through the electric machine of the motor vehicle of Fig. 1, Fig. 3 an enlarged view of a cross-section of the electric machine of the motor vehicle of the Fig. 1, Fig. 4 an enlarged view of a portion of the Fig. 2 shown longitudinal section, whereby this area is Fig. 2 is indicated by a box IV, Fig. 5 - 7 several views of one of the windings of the component of the electrical machine of the Fig. 2, Fig. 8 a longitudinal section through the electric machine of the motor vehicle of the Fig. 1 concerning one of the windings, Fig. 9 a schematic diagram of one of the windings of the electrical machine of the Fig. 2, and Fig. 10 an enlarged view of a portion of the representation of the Fig. 6 relating to a connecting component, this area being Fig. 6 is indicated by a box X.

[0041] Fig. 1 shows a motor vehicle 1 according to the invention according to an exemplary embodiment, comprising an electric machine according to the invention according to an exemplary embodiment. The electric machine 2 comprises a component 3 according to the invention according to an exemplary embodiment, which in this case is a rotor 4 of the electric machine 2. The electric machine 2 further comprises a stator 5.

[0042] The electric machine 2 is a salient-pole synchronous machine, embodied, for example, as an internal rotor. The rotor 4 is arranged in a region of the electric machine 2 that is radially further inward than a region in which the stator 5 is arranged. A rotor shaft 6 of the rotor 4 is rotatably mounted on a housing 7 of the electric machine 2, for example by means of a ball or roller bearing. The rotor shaft 6 is arranged in a rotor shaft sleeve 58, which is arranged in particular in a rotationally fixed manner and will be discussed in more detail below.

[0043] The electric machine 2 is configured to be operated in a drive mode in which electrical energy stored in an electrical energy storage device 8 of the motor vehicle 1 is converted into kinetic energy of the motor vehicle 1. A generated drive torque, which is used to propel the motor vehicle 1, can be transferred from the electric machine 2 to a drive train 9 of the motor vehicle 1. The drive torque can only be transferred to the rear wheels, but can additionally or alternatively also be transferred to the front wheels. The electric machine 2 can also be operated in a recuperation mode in which kinetic energy of the motor vehicle 1 is converted by means of the electric machine 2 into electrical energy, which can be used, for example, to charge the electrical energy storage device 8.

[0044] Below, definitions regarding relevant spatial directions are introduced with reference to the electric machine 2. The rotor shaft 6 is mounted for rotation about a rotation axis 10, which extends along a longitudinal direction 11 of the electric machine 2. A radial direction 12 extends perpendicular to the longitudinal direction 11. A circumferential direction 13 is perpendicular to the radial direction 12. This means that a point rotating about the rotation axis 10 moves along the circumferential direction 13.

[0045] Below, details regarding component 3 and rotor 4 are given based on the Fig. 2 and Fig. 3 explained. Fig. 2 shows a sectional view of component 3, with the cutting plane running along the rotation axis 10. Fig. 3 shows a sectional view of component 3, with the section plane perpendicular to the rotation axis 10. In particular, based on the Fig. 3 shows that component 3, i.e., rotor 4, is composed of several parts 14. Each of the parts 14 comprises a tooth 15 extending along the radial direction 12, around which a respective winding 16 is wound. Component 3 is manufactured by assembling the component 3 from the several parts 14, with conductor wires 20 of the windings 16 previously being wound around the respective tooth 15.

[0046] Details regarding the geometry of the parts 14 are explained below. For example, exactly one tooth 15 is provided for each part 14. Each of the six parts 14 is segment-shaped. Along the circumferential direction 13, a total of six teeth 15 are provided, forming a star-like structure. Between adjacent teeth 15, receiving grooves 53 are formed, in which the windings 16 are arranged or through which the windings 16 extend.

[0047] The segment-like parts 14 each have two lateral outer sides 50 that are angled to one another and are in contact with the lateral outer sides 50 of adjacent parts 14. The opening angle between the lateral outer sides 50 is identical for all parts and amounts to 60°. The lateral outer sides 50 can converge to a point on the radial inside or, as in the present exemplary embodiment, can be separated from one another by an inner outer side 51 of the respective part 14. The inner outer side 51 is circularly curved when viewed along the longitudinal direction 11. The lateral outer sides 50 are separated from one another on the radial outside by an outer outer side 52 of the respective part 14, with the tooth 15 being arranged on the outer outer side 52. The lateral outer sides 50 that are angled to one another are thus arranged at a distance from one another, with the inner outer side 51 and the outer outer side 52 extending therebetween.The outer sides 52 each represent a part of a groove base of one of the receiving grooves 53.

[0048] The parts 14 are arranged next to one another on the rotor shaft 6 along the circumferential direction 13. The inner outer side 51 of the respective part 14 is in contact with the rotor shaft 6 and is fastened thereto. Specifically, the inner outer side 51 of the respective part 14 and a radial outer side 54 of the rotor shaft 6 each have a toothing 17, wherein the toothings 17 engage with one another. To fasten the parts 14 to the rotor shaft, a welded and / or soldered and / or screwed and / or riveted connection can be provided additionally or alternatively.

[0049] The teeth 15 each have a T-shape with a longitudinal beam 18 and a cross beam 19, wherein the longitudinal direction of the longitudinal beam 18 extends along the radial direction 12 and the longitudinal direction of the cross beam 19 along the circumferential direction 13. The winding 16 is wound around the longitudinal beam 18. The cross beam 19 is bent radially on the outside, wherein between the tooth 15 forming a pole shoe and the stator 5, which in Fig. 3 is not shown, forms an air gap 23 a few millimeters wide.

[0050] Below, details regarding the windings 16 are given based on the Fig. 4, which is an enlarged view of the Fig. 2 represents the box marked IV. Each of the windings 16 is formed from electrically conductive conductor wires 20, which each have hollow cross-sections to form a cooling channel 26 through which a cooling fluid can be passed. The cooling fluid in this case is, for example, a cooling liquid, namely water or oil. The conductor wires 20 each consist of a metal, namely copper. The outer cross-section of the conductor wire 20 is, for example, rectangular and has rounded corners. It is also conceivable for the outer cross-section to be round, in particular elliptical or circular. The inner cross-section of the conductor wire 20, i.e. an outer cross-section of the cooling channel 26 formed by the respective conductor wire 20, is circular. However, this inner cross-section can also be elliptical or rectangular and, in particular, have rounded corners.

[0051] Each of the conductor wires 20 has one of the cooling channels 26, which extends along the longitudinal direction of the respective conductor wire 20 and is closed laterally. Each of the conductor wires 20 has an opening exclusively at its front or end ends, i.e., at its end faces, which each form an inlet or outlet opening of the cooling channel 26. The cooling fluid is supplied to the conductor wire 20 or cooling channel 26 via one of these openings and is discharged from the conductor wire 20 or cooling channel 26 via the other opening.

[0052] Furthermore, the electric machine 2 has a cooling system 21 (see Fig. 2) that forms a cooling circuit in which the cooling fluid can be conveyed by means of a conveying means 22, which in this case is a cooling fluid pump. The cooling circuit, or rather a portion of the path taken by the cooling fluid as it flows through the cooling circuit, is indicated in the figures by wavy arrows. To guide the cooling fluid, the rotor shaft 6 has a supply channel 24 extending along the longitudinal direction 11, which is in particular a central or longitudinal bore of the rotor shaft 6, and a discharge channel 25 running parallel thereto. Further details regarding the channels 24, 25 are explained below.

[0053] Below, details of the structure of the winding 16 are given using the Fig. 5 to 9. The Fig. 5 to 7 show different schematic views of one of the windings 16, wherein further components of component 3 are omitted for better visibility. Fig. 5 shows the winding 16 in a frontal view looking along the longitudinal direction 11. Fig. 6 shows the winding 16 in a perspective view. Fig. 7 shows the winding 16 in a plan view looking along the radial direction 12. Fig. 8 shows a similar representation as Fig. 4, wherein the area of ​​the winding 16 is shown enlarged and the sectional plane is rotated by an angle around the rotation axis 10 such that it runs centrally through connecting components 30, 33, 36, which are explained in more detail below. Fig. Figure 9 shows a much simplified representation of the Fig. 8, which makes the structure of the winding 16 easier to understand.

[0054] As can be seen from the Fig. 5 to 9, the winding 16 has, relative to the radial direction 12, a plurality of winding layer groups 27 arranged one above the other, wherein each of the winding layer groups 27 comprises, for example, a winding layer 28. Alternatively, at least one of the winding layer groups 27 can also have, relative to the radial direction 12, a plurality of winding layers 28 arranged one above the other. Thus, in the present case, each of the winding layers 28 comprises a plurality of winding circuits 29 forming a spiral structure, wherein the conductor wire 20 extends exactly once completely around the tooth 15 within one winding circuit 29. A total of nine winding layer groups 27 are provided.

[0055] With regard to the winding layer groups 27, it is provided that the one-piece conductor wire 20 forming the respective winding layer group 27 has an input-side end section 31 and an output-side end section 34. The end sections 31, 34 comprise the front ends or end faces of the respective conductor wire 20, wherein an inlet or outlet opening of the cooling channel 26 of the respective conductor wire 20 is arranged there. As can be seen in particular from the Fig. 7 and Fig. 8, the end sections 31, 34 protrude laterally and along the longitudinal direction 11 from the winding 16.

[0056] As can be seen in particular from the Fig. 8 and Fig. As can be seen from Figure 9, several fluidic input connection components 30 are provided, by means of which the input-side end sections 31 of two adjacent winding layer groups 27 are connected to a fluidically upstream supply chamber 32 in such a way that these winding layer groups 27 are fluidically connected in parallel. A total of four fluidic input connection components 30 are provided, which, as can be seen from the Fig. 5, are arranged offset from one another along the radial direction 12. Due to the position of the cutting plane, Fig. 8 and Fig. 9 only some of the fluidic input connection components 30 are visible, whereby in Fig. 9 the non-visible fluidic input connection components 30 are indicated by dashed lines. As can be seen from the Fig. 9, the second and third, the fourth and fifth, the sixth and seventh, and the eighth and ninth winding layer groups 27 are each connected to one of the fluidic input connection components 3, relative to the radial direction 12 outwards.

[0057] Furthermore, several fluidic output connection components 33 are provided, by means of which the output-side end sections 34 of two adjacent winding layer groups 27 are fluidically connected to a discharge chamber 35, which is fluidically connected downstream of these. A total of four fluidic output connection components 33 are provided, which, like the fluidic input connection components 30, are arranged offset from one another along the radial direction 12. The Fig. The fluidic input connection components 33 not visible in FIG. 9 are indicated by dashed lines. Relative to the outward radial direction 12, the first and second, the third and fourth, the fifth and sixth, and the seventh and eighth winding layer groups 27 are each connected to one of the fluidic output connection components 33.

[0058] With regard to the fluidic connecting components 30, 33, it is thus provided that they are each fluidically connected upstream or downstream of an adjacent pair of winding layer groups 27. The cooling fluid flow flowing through the supply chamber 32 is divided between the two downstream winding layer groups 27 by means of the fluidic input connecting components 30, whereby the resulting partial flows flowing parallel through the winding layer groups 27 pass through the fluidic output connecting components 33 into the discharge chamber 35 and are reunited there.

[0059] For electrical contacting of the winding layer groups 27, electrical connecting components 36 are provided, which each connect the end sections 31, 34 of two adjacent winding layer groups 27 to one another, so that these winding layer groups 27 are electrically connected in series. Specifically, it is provided that the end sections 31, 34 of the conductor wires 20 of all pairwise adjacent winding layer groups 27 of the winding 16 are each connected to one another via an electrical connecting component 36, so that all winding layer groups 27 of the respective winding 16 are electrically connected in series one after the other. The electrical current is guided in Fig. 9 indicated by dotted arrows.

[0060] With regard to the electrical connection components 36, it is provided that one part of them forms the fluidic input connection components 30 and another part of them forms the fluidic output connection components 33. Each electrical connection component 36 thus forms a fluidic connection component 30, 33 and vice versa, so that in this respect a common connection component 30, 33, 36 is realized. Thus, in this regard, it can generally be provided that at least one of the electrical connection components 36 forms one of the fluidic input connection components 30 or one of the fluidic output connection components 36, so that these two components are a common component.

[0061] Fig. 10 shows a perspective and enlarged view of one of the common connecting components 30, 33, 36. Specifically shown is the topmost of the Fig. 6 shown connecting component 30, 33, 36, wherein the display area of ​​the Fig. 10 in Fig. 6 is marked by a box X. Accordingly, the connecting components 30, 33, 36 each comprise a base body 37 made of an electrically conductive material, namely a metal such as copper. This creates the required electrical contact between the adjacent winding layer groups 27. The base body 37 comprises two channels 38, each forming a connection interface, through which the cooling fluid can be guided. For this purpose, the respective end sections 31, 34 are inserted into the channels 38 or plugged in in a fluid-tight clamping manner, which also establishes the electrical contact. The inner cross-section of the channels 38 corresponds to the outer cross-section of the end section 31, 34 plugged into them. Instead of the channels 38, the base body 37 can have at least one chamber for guiding the cooling fluid.

[0062] Related to the Fig. 4, Fig. 8 and Fig. 9, an input connection component 55 and an output connection component 56 are provided, which, apart from the aspects explained below, correspond to the connection components 30, 33, 36. With particular reference to the Fig. 4 and Fig. 8, the input connection component 55 has a longitudinal section 44 that extends through the supply chamber 32, so that an electrical contacting head 45, via which the electrical contact can be made from the outside with the respective winding 16, is arranged on the outside of a supply part 40, which will be explained below. An opening 46, in particular a slot-like opening, is provided laterally on the longitudinal section 44, through which the cooling fluid flows from the supply chamber 32 into the respective end section 31. The output connection component 56 also has a longitudinal section 44 that extends through the discharge chamber 35, so that an electrical contacting head 45, via which the electrical contact can be made from the outside with the respective winding 16, is arranged on the outside of a discharge part 41, which will be explained below.An opening 46, in particular a slot-like opening, is provided laterally on the longitudinal section 44 of the output connection component 56, through which the cooling fluid flows from the respective end section 34 into the discharge chamber 35.

[0063] The following are based on the Fig. 4 and Fig. 8 Details regarding the implementation of the supply chamber 32 and the discharge chamber 35 are explained. Thus, with respect to the longitudinal direction 11, supply parts 39 are arranged next to the winding 16, so that the winding 16 is arranged between the supply parts 39. One of the supply parts 39 is the supply part 40, which has the supply chamber 32. The other of the supply parts 39 is the discharge part 41, which has the discharge chamber 35. The supply parts 39 are each made of a plastic and have an annular shape that extends concentrically around the rotor shaft 6. Accordingly, the supply chamber 32 and the discharge chamber 35 are also annular and arranged concentrically around the rotor shaft. The supply chamber 32 and the discharge chamber 35 thus each form a common chamber that is fluidically connected upstream or downstream of all end sections 31, 34 of all windings 16.

[0064] As can be seen in particular from the Fig. As can be seen in Figure 8, the supply parts 39 each have receiving openings 42 which open into the feed chamber 32 and the discharge chamber 35, respectively. The receiving openings 42 are essentially cylindrical and adapted to the shape of the connecting components 30, 33, 36 and the components 55, 56. The connecting components 30, 33, 36 and the components 55, 56 are fastened to the supply part 39 by being inserted into one of the receiving openings 42. Both the receiving openings 42 and the connecting components 30, 33, 36 and the components 55, 56 have locking means 43 for fastening these components to one another. As locking means 43, locking grooves of the connecting components 30, 33, 36 and the components 55, 56 are provided, into which locking lugs of the receiving openings 42 or of the respective supply part 39 engage.

[0065] Now, with reference to the Fig. 2 and Fig.4 details regarding the specific guidance of the cooling fluid in the cooling system 21 are explained. After the cooling fluid has passed through the conveying means 22, it is introduced into an introduction chamber 47 arranged on the end face of the rotor shaft 6 by means of an introduction lance (not shown in the figures). The cooling fluid flows through the introduction chamber 47 into the supply channel 24 via end-face openings 49 of the rotor shaft 6, which are arranged at its conveying-means-side end. After the cooling fluid has flowed through the supply channel 24 and reached a winding-side end of the rotor shaft 6, it exits the rotor shaft 6 via lateral openings 57, particularly due to the centrifugal force generated by the rotation of the rotor shaft 6. The cooling fluid then enters the supply chamber 32 through first transverse bores 59 in the rotor shaft sleeve 58.Subsequently, the cooling fluid flows through the winding 16 as described above and then enters the discharge chamber 35. From there, due to the following cooling fluid, it is guided into a cooling fluid channel of a connecting part 48, which opens into second transverse bores 60 in the rotor shaft sleeve 58. The second transverse bores 60 open into the discharge channel 25. This has a hollow cylindrical or sleeve-like geometry and extends between the rotor shaft 6 and the rotor shaft sleeve 58 along the longitudinal direction 11, so that the cooling fluid flows back to the conveying-means-side end of the rotor shaft 6 and is fed there to the conveying means 22.

[0066] Although component 3 according to the invention forms the rotor 4 of the electric machine 2 in the illustrated embodiment, it is equally conceivable within the scope of the present invention for the stator 5 to implement component 3 and the aspects explained thereby. In this case, in particular, the teeth 15, the windings 16, and the aspects explained thereby are implemented in the stator 5.

Claims

[1] An electrical machine comprising at least one component (3) forming either a stator (4) or a rotor (5), which component has at least two teeth (15) each extending along a radial direction (12) of the electrical machine (2), each having a winding (16) wound therearound, wherein at least one of the windings (16) comprises a plurality of winding layer groups (27) arranged one above the other with respect to the radial direction (12), wherein each of the winding layer groups (27) comprises one or more winding layers (28) arranged one above the other, wherein the winding layer groups (27) are each formed from a separate and electrically conductive conductor wire (20), wherein the electrical machine (2) has a cooling system (21) by means of which a cooling fluid can be guided through a hollow cross-section of at least two conductor wires (20) in such a way that at least two of the winding layer groups (27) are fluidically connected in parallel. [2] Electrical machine according to claim 1, characterized by that it is designed as a salient pole synchronous machine. [3] Electrical machine according to claim 1 or 2, characterized by one or more fluidic input connection components (30), by means of which or by means of which respective input-side end sections (31) of the conductor wires (20) of at least two winding layer groups (27) are fluidically connected to one or more feed chambers (32), which are or are fluidically connected upstream of these conductor wires (20), in such a way that these winding layer groups (27) are fluidically connected in parallel. [4] Electrical machine according to one of the preceding claims, characterized byone or more fluidic output connection components (33), by means of which or by means of which respective output-side end sections (34) of the conductor wires (20) of at least two winding layer groups (27) are fluidically connected to one or more discharge chambers (35) which are respectively fluidically connected downstream of these conductor wires (20). [5] Electrical machine according to claim 3 or 4, characterized by one or more supply parts (39), each of which is or are arranged next to at least one of the windings (16) in relation to a longitudinal direction (11) of the electrical machine (2), wherein the or at least one of the plurality of supply parts (39) is designed as a feed part (40) and has the or at least one of the plurality of feed chambers (32), or wherein the or at least one of the plurality of supply parts (39) is designed as a discharge part (41) and has the or at least one of the plurality of discharge chambers (35). [6] Electrical machine according to claim 5, characterized by that the or at least one of the plurality of supply parts (39) is formed in a ring shape and is arranged concentrically around the or a rotor shaft (6) extending along the longitudinal direction (11) and mounted for rotation, of the component (3) forming the rotor (4), wherein the or at least one of the plurality of supply chambers (32) and / or the or at least one of the plurality of discharge chambers (35) is formed in a ring shape and is arranged concentrically around the rotor shaft (6). [7] Electrical machine according to claim 5 or 6, characterized by that the or at least one of the plurality of fluidic input connection components (30) and / or the or at least one of the plurality of fluidic output connection components (33) is fastened to the supply part (39). [8] Electrical machine according to one of the preceding claims, characterized byone or more electrical connecting components (36) which each connect or connect end sections (31, 34) of the conductor wires (20) of two adjacent winding layer groups (27) of one of the windings (16) to one another, so that these winding layer groups (27) are electrically connected in series. [9] Electrical machine according to claim 8, characterized by that the end sections (31, 34) of the conductor wires (20) of all pairwise adjacent winding layer groups (27) of the respective winding (16) are connected to one another via an electrical connecting component (36), so that all winding layer groups (27) of the respective winding (16) are electrically connected in series one after the other. [10] Electrical machine according to one of claims 3 to 7 and according to one of claims 8 or 9, characterized bythat at least one common connection component (30, 33, 36) is provided, which forms the or one of the plurality of fluidic connection components (30, 33) and the or one of the plurality of electrical connection components (36). [11] Electrical machine according to claim 10, characterized by in that the at least one common connecting component (30, 33, 36) has a base body (37) made of an electrically conductive material, wherein the base body (37) has at least one channel (38) and / or at least one chamber through which the cooling fluid can be guided. [12] Electrical machine according to one of the preceding claims, characterized byin that the cooling system (21) forms a cooling circuit in which the cooling fluid can be conveyed by means of a conveying means (22), wherein the rotor shaft (6) of the component (3) forming the rotor (4), or a rotor shaft (6) extending along a longitudinal direction (11) of the electrical machine (2) and mounted for rotation, has or delimits at least one supply channel (24) and / or at least one discharge channel (25), wherein the supply channel (24) and / or the discharge channel (25) extends at least in sections along the longitudinal direction of the rotor shaft (6), wherein the supply channel (24) leads from the conveying means (22) to at least one of the conductor wires (20) having the hollow cross section and / or the discharge channel (25) leads from at least one of the conductor wires (20) having the hollow cross section to the conveying means (22). [13] Electrical machine according to one of the preceding claims, characterized bythat the component (3) is assembled from several parts (14), wherein at least two of the parts (14) each have at least one of the teeth (15). [14] Component for an electrical machine (2), designed as a stator (4) or a rotor (5) and having at least two teeth (15) each extending along a radial direction (12) of the component (3), each with a winding (16) wound around it, wherein at least one of the windings (16) comprises a plurality of winding layer groups (27) arranged one above the other with respect to the radial direction (12), wherein each of the winding layer groups (27) comprises one or more winding layers (28) arranged one above the other, wherein the winding layer groups (27) are each formed from a separate and electrically conductive conductor wire (20), wherein a cooling fluid of a cooling system (21) of the electrical machine (2) can be guided through a hollow cross section of at least two conductor wires (20) in such a way that at least two of the winding layer groups (27) are fluidically connected in parallel. [15] Motor vehicle comprising an electric machine (2) according to one of claims 1 to 13.

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