Axial flux machine, electric axle drivetrain, and motor vehicle

Abstract

The invention relates to an axial flux machine (1), comprising a rotor (3) mounted rotatably relative to a stator (2), wherein: the stator (2) has at least one first disc-shaped stator body (21), and the rotor (3) and also the first stator body (21) are arranged such that a first magnetically active gap (24a) running in a radial plane (9) is formed axially between the first stator body (21) and the rotor (3); the stator (2) is surrounded at least in portions by a motor housing (4); a ring-segment-shaped groove (5) which is open towards the first stator body (21) and extends in a radial plane (8) is formed; and a plurality of cooling openings (6) are provided in the motor housing (4) in the region of the ring-segment-shaped groove (5), by means of which cooling openings a cooling fluid (7) that can be introduced into the ring-segment-shaped groove (5) can be applied to the first stator body (21).

Description

[0001] Axial flux machine, electric axle drive train and motor vehicle

[0002] The present invention relates to an axial flux machine comprising a rotor rotatably mounted relative to a stator, wherein the stator has at least one first disc-shaped stator body, and the rotor and the first stator body are arranged such that a first magnetically active gap a extending in a radial plane is formed axially between the first stator body and the rotor, and the stator is at least partially enclosed by a motor housing. The invention further relates to an electric axle drive train and a motor vehicle.

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

[0004] A detailed description of an electric drive can be found in an article in the magazine ATZ 113th year, 05 / 2011, pages 360-365 by Erik Schneider, Frank Fickl, Bernd Cebulski and Jens Liebold with the title: Highly integrated and flexible electric drive unit for electric vehicles. This article describes a drive unit for one axle of a vehicle which comprises an electric motor which is arranged concentrically and coaxially to a bevel gear differential, with a switchable 2-speed planetary gear set arranged in the power train between the electric motor and bevel gear differential, which is also positioned coaxially to the electric motor or the bevel gear differential or spur gear differential. The drive unit is very compact and, thanks to the switchable 2-speed planetary gear set, allows a good compromise between climbing ability, acceleration and energy consumption.Such drive units are also referred to as e-axles or electrically operated drive trains.

[0005] In addition to purely electric drivetrains, hybrid drivetrains are also known. Such drivetrains in hybrid vehicles typically comprise a combination of an internal combustion engine and an electric motor, enabling purely electric operation—for example, in urban areas—while maintaining sufficient range and availability, especially for long-distance journeys. Furthermore, in certain operating situations, it is possible to use both the internal combustion engine and the electric motor simultaneously.

[0006] An axial flux machine is a dynamoelectric machine in which the magnetic flux between the rotor and stator runs parallel to the rotor's axis of rotation. Both the stator and rotor are often largely disk-shaped. Axial flux machines are particularly advantageous when the axial space available in a given application is limited. This is often the case, for example, with the electric drive systems for electric or hybrid vehicles described above.

[0007] In addition to the shorter axial length, another advantage of the axial flux machine is its comparatively high torque density. This is due to the larger air gap area available in a given installation space compared to radial flux machines. Furthermore, a smaller iron volume is required compared to conventional machines, which has a positive effect on the machine's efficiency.

[0008] Typically, an axial flux machine comprises at least one stator with windings for generating the axially aligned magnetic field. At least one rotor is equipped with permanent magnets, for example, whose magnetic field interacts with the magnetic field of the stator windings to generate a drive torque across an air gap.

[0009] In the development of electric machines intended for e-axles and hybrid modules, there is a continuing need to increase their power densities, so that the cooling of axial-flow machines required for this purpose is becoming increasingly important. Due to the necessary cooling capacities, hydraulic fluids, such as cooling oils, have become established in most concepts for dissipating heat from the thermally stressed areas of an electric machine. However, these cooling strategies are often inadequate and / or associated with high costs in technical implementation. The object of the invention is therefore to eliminate or at least mitigate the problems known from the prior art and to provide an axial-flow machine with an effective and cost-effective cooling system.

[0010] This object is achieved by an axial flux machine comprising a rotor rotatably mounted relative to a stator, wherein the stator has at least a first disc-shaped stator body and the rotor and the first stator body are arranged such that a first magnetically active gap a extending in a radial plane is formed axially between the first stator body and the rotor, and the stator is at least partially enclosed by a motor housing, wherein an annular segment-shaped groove is formed on the motor housing and is open towards the first stator body and extends in a radial plane, and in the region of the annular segment-shaped groove a plurality of cooling openings are provided in the motor housing, by means of which cooling openings a cooling fluid that can be introduced into the annular segment-shaped groove can be applied to the first stator body.

[0011] This provides the advantage of particularly efficient cooling fluid transfer and distribution between the motor housing and the stator of the axial-flow machine. Furthermore, the cooling fluid transfer and distribution via the ring-segment-shaped groove also allows for a particularly compact axial design.

[0012] Furthermore, the configuration according to the invention allows only the housings to be adapted for different installation space situations, but the electrical machine as such to be designed identically in each case, whereby installation space-specific adaptation is correspondingly simplified and can also be manufactured more cost-effectively.

[0013] For example, by cooling a stator over the entire surface through the ring-segment-like groove, cooling of the rotor of the electric machine can also be achieved, which further improves the cooling performance.

[0014] The ring segment-shaped groove is located axially on one side of the

[0015] Axial flux machine and is open to the axial flux machine. The housing of the axial flux machine contains cooling openings extending axially through the housing, allowing the cooling fluid to flow into the axial flux machine and thereby cool the first stator body of the axial flux machine.

[0016] It is understood that a ring-segment-shaped groove can also be designed to be closed all the way around.

[0017] First, the individual elements of the claimed subject matter of the invention are explained in the order in which they appear in the set of claims, and subsequently, particularly preferred embodiments of the subject matter of the invention are described.

[0018] The magnetic flux in an electric axial flux machine (AFM) according to the invention is directed axially in the magnetically effective gap between stator and rotor relative to a rotational direction of the rotor of the axial flux machine. There are different types of axial flux machines. The axial flux machine according to the invention can be configured as an I-type. In principle, it is also possible for a plurality of I-type and / or H-type rotor-stator configurations to be arranged axially next to one another. In this context, it would also be possible to arrange one or more I-type rotor-stator configurations and one or more H-type rotor-stator configurations next to one another in the axial direction. In particular, it is also preferable for the H-type and / or I-type rotor-stator configurations to be essentially identical, so that they can be combined in a modular manner to form an overall configuration.Such rotor-stator configurations can in particular be arranged coaxially to one another and connected to a common rotor shaft or to several rotor shafts.

[0019] According to a further preferred development of the invention, it can also be provided in particular that the stator comprises at least one second disc-shaped stator body, which is arranged coaxially to the first stator body and to the rotor shaft, with one of the rotor bodies axially arranged therebetween and spaced from the first stator body, so that an I-configuration of an axial flux machine is realized.

[0020] A rotor may also have a rotor shaft. A rotor shaft is a rotatably mounted shaft of an electrical machine to which the rotor or rotor body is rotationally fixedly coupled.

[0021] In this context, it is particularly preferred that the rotor has a rotor shaft with at least one first disc-shaped rotor body arranged in a rotationally fixed manner on the rotor shaft, which allows for cost-efficient production by dividing the rotor into magnetically active components (rotor body) and purely mechanical components (rotor shaft). In particular, this also makes it possible to design the various I and / or Fl configurations mentioned above in a particularly flexible manner.

[0022] The rotor of an electric axial flux machine can preferably be designed, at least in part, as a laminated rotor. A laminated rotor is designed with layers in the axial direction. Alternatively, the rotor of an axial flux machine can also have a rotor carrier or rotor body, which is equipped with magnetic laminations and / or SMC material and with magnetic elements designed as permanent magnets.

[0023] A rotor can comprise a rotor body. A rotor body preferably has an inner part, via which the rotor can be connected to a shaft in a rotationally fixed manner, and an outer part that delimits the rotor in the radial outward direction. The rotor body can be formed between the inner part and the outer part with a plurality of rotor struts, via which the inner part and the outer part are connected to one another and which, together with the radial outer surface of the inner part and the radial inner surface of the outer part, forms a receiving space for the magnetic elements and the flux-guiding elements of the rotor. As an alternative to the receiving space, the magnetic elements can be arranged or mounted on the rotor carrier. A magnetic element can be formed as a permanent magnet in the form of a bar magnet or in the form of smaller magnetic blocks designed as blocks. The magnetic elements are generally arranged in, on, or on a rotor carrier.The magnetic element of a rotor of an axial flux machine, designed as a permanent magnet, interacts with a rotating magnetic field which is generated by the stator winding coils which are usually supplied with a three-phase current.

[0024] The stator of an electric axial flux machine preferably has a stator body with a plurality of stator windings arranged in the circumferential direction. The stator body can be formed as a single piece or segmented in the circumferential direction. The stator body can be formed from a stator core with a plurality of laminated electrical sheets. Alternatively, the stator body can also be formed from a pressed soft magnetic material, such as the so-called SMC (Soft Magnetic Compound).

[0025] The axial flux machine can have a motor housing. The motor housing encloses the axial flux machine at least partially, preferably completely. A motor housing can also accommodate the control and power electronics. The motor housing can also be part of a cooling system for the electric machine and can be designed such that cooling fluid can be supplied to the axial flux machine via the motor housing and / or heat can be dissipated to the outside via the housing surfaces.

[0026] A motor housing can, in particular, be formed from a metallic material. Advantageously, the motor housing can be formed from a metallic cast material, such as gray cast iron or cast steel. In principle, it is also conceivable to construct the motor housing entirely or partially from a plastic. Particularly preferably, the motor housing has a cylindrical, ring-shaped basic shape. The motor housing can be constructed in one piece or in multiple pieces. It can also be advantageous for one or more stator supports to be formed integrally with the motor housing, at least in sections, which can further improve the ease of assembly of the axial flux machine.According to an advantageous embodiment of the invention, it can be provided that a first disc-shaped stator body and / or a second disc-shaped stator body are / is designed as a circuit board, in particular as a printed circuit, which is also referred to as a printed circuit board PCB, whereby the stator body can be produced particularly compactly and cost-effectively. The winding of the stator body is formed integrally with the circuit board. The circuit board is preferably a multilayer board with several copper layers over which the stator windings extend. A further possible embodiment is the design of the stator body as a sandwich of several multilayer boards. The circuit board is preferably formed from a composite of epoxy resin and glass fiber.

[0027] The axial flux machine is intended in particular for use within an electrically operated drive train of a motor vehicle. In particular, the axial flux machine is dimensioned such that vehicle speeds greater than 50 km / h, preferably greater than 80 km / h, and in particular greater than 100 km / h can be achieved. The axial flux machine particularly preferably has an output greater than 30 kW, preferably greater than 50 kW, and in particular greater than 70 kW. It is further preferred that the axial flux machine provides speeds greater than 5,000 rpm, more preferably greater than 10,000 rpm, and most preferably greater than 12,500 rpm.

[0028] According to an advantageous embodiment of the invention, it can be provided that the number of cooling openings corresponds to the number of coils of the first stator body, so that efficient cooling of each individual coil can be provided.

[0029] According to a further preferred development of the invention, it can also be provided that the ring-segment-shaped groove is hydraulically connected to a cooling channel section extending radially outward, which in turn is hydraulically connected to the output side of a heat exchanger via a hydraulic coupling means. This can ensure that the cooling fluid is conveyed from the heat exchanger via the cooling channel section into the ring-segment-shaped groove.

[0030] Furthermore, according to a similarly advantageous embodiment of the invention, a pressure relief valve can be arranged between the ring-segment-shaped groove and the hydraulic coupling means, which opens into an overflow channel on the outlet side. The advantageous effect of this embodiment is that the hydraulic system of the stator cooling can be protected from overpressure and any resulting damage.

[0031] According to another particularly preferred embodiment of the invention, a return channel can be formed radially outside the first stator body, through which cooling fluid can be discharged from the first stator body. This can achieve the effect that multiple stators can be connected to the cooling system. Furthermore, this can create the possibility of busbar cooling.

[0032] Furthermore, the invention can also be further developed such that the stator comprises at least one second disc-shaped stator body, which is coaxial with the first stator body and spaced from the first stator body with the rotor axially interposed therebetween, wherein the cooling channel section is connected to at least one first hydraulic path extending axially through the axial flow machine, so that the cooling fluid can be guided to the second disc-shaped stator body. The advantage of this configuration is that the cooling oil can be transported axially from the first to the second stator body, but only one hydraulic connection, namely the coupling means, is required.

[0033] In a likewise preferred embodiment of the invention, the axial flow machine can also be provided with a second hydraulic path extending axially through the axial flow machine and connected to the cooling channel section. This can further improve the hydraulic cooling performance and provide a better distribution of the cooling fluid.

[0034] It may also be advantageous to further develop the invention in such a way that a second ring-segment-shaped groove is formed on the motor housing, which is open towards the second stator body and extends in a radial plane, and in the region of the second ring-segment-shaped groove a plurality of cooling openings are provided in the motor housing and / or on a connecting housing of a higher-level structure, by means of which a cooling fluid which can be introduced into the second ring-segment-shaped groove can be applied to the second stator body, wherein the second groove is connected to the first hydraulic path and / or second hydraulic path, which likewise contributes to improved cooling performance and cooling fluid distribution.

[0035] The object of the invention is further achieved by an electric axle drive train for a motor vehicle, comprising at least two axial flux machines according to one of claims 1-8, whose rotors are arranged coaxially to one another. This makes it possible to drive two vehicle wheels of a vehicle axle separately, each with an axial flux machine.

[0036] An electrically operable drive train thus comprises two electric axial flux machines and preferably a gear assembly coupled to each electric axial flux machine. The gear assembly and the electric axial flux machine form a structural unit. This can be formed, for example, by a drive train housing in which the gear assembly and the electric axial flux machine are jointly housed.

[0037] The electric machine preferably has a motor housing and / or the gearbox a gearbox housing, whereby the structural unit is then achieved by fixing the gearbox relative to the electric machine. The gearbox housing is a housing for accommodating a gearbox. Its task is to guide existing shafts via the bearings and to grant the wheels (and possibly cam disks) the degrees of freedom they require under all loads without hindering their rotational and possibly path-related movement, as well as to absorb bearing forces and support moments. A gearbox housing can be single- or multi-shell, i.e., undivided or split. In particular, the gearbox housing should also dampen noise and vibrations and be able to safely accommodate hydraulic fluid.The gear housing is preferably formed from a metallic material, particularly preferably from aluminum, gray cast iron or cast steel, in particular by means of a primary forming process such as casting or die casting.

[0038] The transmission arrangement can be coupled, in particular, to the electric motor, which is designed to generate a drive torque for the motor vehicle. The drive torque is particularly preferably a main drive torque, so that the motor vehicle is driven exclusively by the drive torque. The transmission arrangement is preferably designed as a planetary gear, most preferably as a switchable, in particular two-speed planetary gear.

[0039] Finally, the object of the invention can also be achieved by a motor vehicle having a first electric axle drive train according to claim 9 on a first vehicle axle and a second electric axle drive train according to claim 9 on a second vehicle axle. This makes it possible, in particular, for each vehicle wheel of a two-axle motor vehicle to be driven by a respective axial flux machine assigned to it.

[0040] For the purposes of this application, motor vehicles are defined as land vehicles that are propelled by mechanical power without being tied to railway tracks. A motor vehicle can, for example, be selected from the group of passenger cars (PCs), trucks (HGVs), mopeds, light motor vehicles, motorcycles, buses (KOM), or tractors.

[0041] The invention will be explained in more detail below with reference to figures without limiting the general inventive concept. It shows:

[0042] Figure 1 is a schematic hydraulic block diagram of an axial flow machine in an axial section,

[0043] Figure 2 shows an axle drive train with two axial flow machines in an axial sectional view,

[0044] Figure 3 shows a first embodiment of hydraulic lines and paths of the axial flow machine in a cut-out cross-sectional view,

[0045] Figure 4 shows a second embodiment of hydraulic lines and paths of the axial flow machine in a cut-out cross-sectional view,

[0046] Figure 5 shows a first cross-sectional view of the motor housing of the axial flow machine,

[0047] Figure 6 shows a second cross-sectional view of the motor housing of the axial flow machine,

[0048] Figure 7 shows a third cross-sectional view of the motor housing of the axial flow machine,

[0049] Figure 8 shows a motor vehicle with two electrically driven vehicle axles in a schematic block diagram.

[0050] Figure 1 shows an axial flux machine 1, comprising a rotor 3 rotatably mounted relative to a stator 2, wherein the stator 2 has a first disc-shaped stator body 21 and the rotor 3 and the first stator body 21 are arranged such that a first magnetically active gap 28 extending in a radial plane 9 is formed axially between the first stator body 21 and the rotor 3.

[0051] The stator 2 is at least partially enclosed by a motor housing 4. Formed on the motor housing 4 is an annular segment-shaped groove 5 which is open towards the first stator body 21 and extends in a radial plane 8. In the region of the annular segment-shaped groove 5, a plurality of cooling openings 6 are provided in the motor housing 4, by means of which a cooling fluid 7 which can be introduced into the annular segment-shaped groove 5 can be applied to the first stator body 21. The number of cooling openings 6 corresponds to the number of coils 10 of the first stator body 21. As indicated in Figure 1, the cooling fluid 7 can also flow around the coils 10, for example by providing corresponding channels in the stator body 21. The cooling openings 6 for the cooling fluid 7 are selected such that the most efficient cooling of the coils 10 or the stator bodies 21, 22 can be ensured.

[0052] For space reasons, the two axial flow machines 1 are located directly and immediately axially adjacent to each other. The axial flow machine 1 is cooled here with a cooling fluid 7, which is pumped by a pump (not shown) from a sump (also not shown) through the heat exchanger 13.

[0053] Figure 1 further shows that the stator 2 comprises a second disc-shaped stator body 22, which is coaxial with the first stator body 21 and spaced from the first stator body 21 with the rotor 3 axially interposed, wherein the cooling channel section 11 is connected to at least one first hydraulic path 23 extending axially through the axial flow machine 1, so that the cooling fluid 7 can be guided to the second disc-shaped stator body 22. The axial flow machine 1 further has a second hydraulic path 24 extending axially through the axial flow machine 1 and connected to the cooling channel section 11.

[0054] Figure 1 also shows that a second ring-segment-shaped groove 26 is formed on the motor housing 4, which is open towards the second stator body 22 and extends in a radial plane 25, and in the region of the second ring-segment-shaped groove 26, a plurality of cooling openings 27 are provided in the motor housing 4, by means of which cooling openings 27 a cooling fluid 7 which can be introduced into the second ring-segment-shaped groove 26 can be applied to the second stator body 22, wherein the second groove 26 is connected to the first hydraulic path 23 and / or second hydraulic path 24.

[0055] Figure 2 shows a section through an electrically operable axle drive train 30, such as might be installed, for example, in the front axle 33 of a motor vehicle 31, which is sketched as an example in Figure 8. In this exemplary embodiment, two independent axial flux machines 1 are installed, which are constructed in a mirrored manner. In the example shown, such an axle drive train 30 consists of one axial flux machine 1 each with a gear arrangement assigned to it, but not visible in Figure 2.

[0056] As can be seen from Figure 8, the rear axle 32 of a motor vehicle 31 can also consist of two mirrored and independent systems, as shown in Figure 2. Preferably, the axial flow machines 1 in the motor vehicle 31 are designed to be substantially identical.

[0057] Figure 3 shows a schematic view of the oil distribution channels of the axial flow machine 1, comprising the ring-segment-shaped groove 5. A cooling channel section 11 leads from the output side 12 of the heat exchanger 13 into the ring-segment-shaped groove 5, which is arranged on the gearbox side but is open towards the axial flow machine 1. The oil line in the ring-segment-shaped groove 5 is only indicated here as an example. In order to improve an even distribution of the cooling fluid 7, it is expedient, for example, to arrange a channel 18 between hydraulic paths 23, 24 and thus connect them hydraulically. Figure 3 shows an embodiment without this channel 18. In principle, it would also be conceivable for the annular groove 5 to not run in a closed manner between the hydraulic paths 23, 24 in the circumferential direction, unlike as shown in Figure 3, but rather to be interrupted between the hydraulic paths 23, 24.

[0058] From the ring segment-shaped groove 5, two outlets lead upwards in a radial direction to the axially extending hydraulic paths 23, 24 in order to enable the oil cooling of the second stator body 22 on the side of the axial flow machine 1 facing away from the gearbox.

[0059] Furthermore, the return channel 17 from the axial flow machine 1 can be seen in Figure 4, which taps the cooling fluid 7 in the direction of gravity at the highest point of the axial flow machine 1 and directs it into the sump, which is not further designated.

[0060] The oil level in the axial-flow machine 1 can be adjusted even at low / stopped flow rates by adjusting the height of the feed point (outlet 12 of the heat exchanger 13) or the highest point of the cooling channel section 11 in the direction of gravity, as well as the height of the cooling openings 6 in the direction of gravity. This prevents overheating of the axial-flow machine.

[0061] The flow rate can also be used to supply additional components simultaneously, for example, via a series or parallel connection. In this case, additional components (gearbox gears, bearings, etc.) downstream of the axial flow machine are supplied with cooling fluid via orifices. The distribution and pressure can be adjusted via the orifices, including those in the outlet to the sump. However, this is not shown in the figures.

[0062] Figure 5 shows a cross-sectional view of an axial flow machine 1 according to the invention. On the transmission side, several axially extending cooling openings 6 are provided in the motor housing 4, which guide the cooling fluid 7 to the transmission-side first stator body 21 of the stator 2.

[0063] In the area of ​​the unspecified electrical connections, the two hydraulic paths 23, 24 are located for cooling the second stator body 22, which faces away from the transmission. The outlets from the ring-segment-shaped groove 5 are sealed here with connectors to the axial-flow machine 1. Of course, it is also conceivable that seals could be installed directly in the motor housing 4 at the outlets or on the axial-flow machine 1, or even that a low leakage level could be achieved.

[0064] Figures 6 and 7 show the cross-sectional side of the axial flow machine 1 facing away from the gearbox. Figure 7 shows the motor housing 4 of the axial flow machine 1 closed by means of a sealing element 29, and Figure 6 shows the open motor housing 4 without the sealing element 29. Below the sealing element 29 are the cooling openings 27, which guide the oil supply into the second stator body 22, where it cools the winding heads, etc., and can then flow out with the return flow from the gearbox-side, second stator body 22 in a groove-like return channel 17 on the outer diameter of the stator 2. In order to be able to distribute the cooling fluid 7 from the two hydraulic paths 23, 24 to the individual cooling openings 27, a contour or channel structure that distributes the cooling fluid 7 in the circumferential direction is located below the sealing element 29.

[0065] In the return channel 17, both volume flows of cooling fluid 7 from the two stator bodies 21, 22 (the stator bodies 21, 22 facing away from the transmission) are combined. The cooling fluid 7 flows from the two stator bodies 21, 22 into the return channel 17 at the circumference of the stator 2, from where it is discharged at the highest point in the direction of gravity and fed to the sump.

[0066] Thus, within an axle drive train 30, the distribution of cooling fluid 7 and supply through the transmission housing is achieved for the first stator body on the transmission side, and the oil distribution for the second stator body 22 facing away from the transmission is realized internally in the motor housing 4 of the axial flow machine 1.

[0067] As shown in Figures 3 and 4, the ring-segment-shaped groove 5 is hydraulically connected to a cooling channel section 11 extending radially outward, which in turn is hydraulically connected to the output side 12 of a heat exchanger 13 via a hydraulic coupling means 14. Figures 3-4 further show that a return channel 17 is formed radially above the first stator body 21, by means of which cooling fluid 7 can be discharged from the first stator body 21.

[0068] As shown in the embodiment of Figure 3, a pressure relief valve 15 is arranged between the ring-segment-shaped groove 5 and the hydraulic coupling means 14, which opens into an overflow channel 16 on the outlet side.

[0069] Finally, Figure 8 shows a motor vehicle 31 having a first electric axle drive train 30, as known from Figure 2, on a first vehicle axle 32 and a second electric axle drive train 30, as known from Figure 2, on a second vehicle axle 33.

[0070] The invention is not limited to the embodiments illustrated in the figures. The above description is therefore not to be considered restrictive, but rather explanatory. The following claims are to be understood in such a way that a stated feature is present in at least one embodiment of the invention. This does not exclude the presence of further features. Where the claims and the above description define 'first' and 'second' features, this designation serves to distinguish between two similar features without establishing a priority.

[0071] List of reference symbols

[0072] 1 axial flux machine

[0073] 2 Stator

[0074] 3 Rotor

[0075] 4 engine housing

[0076] 5 grooves

[0077] 6 cooling holes

[0078] 7 Cooling fluid

[0079] 8 Radial plane

[0080] 9 Radial plane

[0081] 10 coils

[0082] 11 Cooling channel section

[0083] 12 Output page

[0084] 13 heat exchangers

[0085] 14 coupling agents

[0086] 15 Pressure relief valve

[0087] 16 overflow channel

[0088] 17 Return channel

[0089] 18 channel

[0090] 21 Stator body

[0091] 22 Stator body

[0092] 23 Hydraulic path

[0093] 24 Hydraulic path

[0094] 25 Radial plane

[0095] 26 grooves

[0096] 27 cooling openings

[0097] 28 gap

[0098] 29 Sealing element

[0099] 30 Axle drive train

[0100] 31 Motor vehicle

[0101] 32 vehicle axles

[0102] 33 vehicle axle

Claims

Claims Axial flux machine (1) comprising a rotor (3) rotatably mounted relative to a stator (2), wherein the stator (2) has at least one first disk-shaped stator body (21) and the rotor (3) and the first stator body (21) are arranged such that a first magnetically effective gap (28) extending in a radial plane (9) is formed axially between the first stator body (21) and the rotor (3), and the stator (2) is at least partially encompassed by a motor housing (4), characterized in that an annular segment-shaped groove (5) open towards the first stator body (21) and extending in a radial plane (8) is formed on the motor housing (4) and a plurality of cooling openings (6) are provided in the motor housing (4) in the region of the annular segment-shaped groove (5), by means of which a cooling fluid (7) that can be introduced into the annular segment-shaped groove (5) is directed onto the first stator body (21) ) is applicable.An axial flux machine (1) according to claim 1, characterized in that the number of cooling openings (6) corresponds to the number of coils (10) of the first stator body (21). An axial flux machine (1) according to any of the preceding claims, characterized in that the annular segment-shaped groove (5) is hydraulically connected to a cooling channel section (11) extending radially outwards, which in turn is hydraulically connected to the outlet side (12) of a heat exchanger (13) via a hydraulic coupling means (14). An axial flux machine (1) according to one of the preceding claims, characterized in that a pressure relief valve (15) is arranged between the annular segment-shaped groove (5) and the hydraulic coupling means (14), which opens on the outlet side into an overflow channel (16). An axial flux machine (1) according to one of the preceding claims, characterized in that a return channel (17) is formed radially outside the first stator body (21), by means of which cooling fluid (7) can be discharged from the first stator body (21).An axial flux machine (1) according to one of the preceding claims, characterized in that the stator (2) comprises at least one second disk-shaped stator body (22), which is coaxial to the first stator body (21) and spaced apart from the first stator body (21) by an axial intermediate arrangement of the rotor (3), wherein the cooling channel section (11) is connected at least to a first hydraulic path (23) extending axially through the axial flux machine (1), so that the cooling fluid (7) can be guided to the second disk-shaped stator body (22). An axial flux machine (1) according to claim 6, characterized in that the axial flux machine (1) has a second hydraulic path (24) extending axially through the axial flux machine (1) and connected to the cooling channel section (11). Axial flux machine (1) according to one of the preceding claims 6-7, characterized in that a second annular segment-shaped groove (26) open towards the second stator body (22) and extending in a radial plane (25) is formed on the motor housing (4), and a plurality of cooling openings (27) are provided in the motor housing (4) and / or on a connecting housing of a higher-level structure in the region of the second annular segment-shaped groove (26), by means of which a cooling fluid (7) that can be introduced into the second annular segment-shaped groove (26) can be applied to the second stator body (22), wherein the second groove (26) is connected to the first hydraulic path (23) and / or second hydraulic path (24). Electric axle drive train (30) for a motor vehicle (31), comprising at least two axial flux machines (1) according to one of claims 1-8, the rotors (3) of which are arranged coaxially to each other.motor vehicle (31) comprising a first electric axle drive train (30) according to claim 9 on a first vehicle axle (32) and a second electric axle drive train (30) according to claim 9 on a second vehicle axle (33).

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