DE102024002151A1 - Axial flux machine for a motor vehicle and method for assembling such an axial flux machine - Google Patents

Abstract

The invention relates to an axial flux machine (10) for a motor vehicle, comprising at least one stator (12b), at least two rotors (14b, c) which are rotationally fixed to a rotor shaft (16) common to the rotors (14b, c) of the axial flux machine (10), and a housing device (22) which forms at least one axial contact surface (42c) against which the stator (12b) rests in the axial direction of the axial flux machine (10), wherein the housing device (22) has two separately formed and interconnected housing half-shells (44, 46) whose separating surfaces (48, 50), via which the housing half-shells (44, 46) are at least indirectly assembled and at least indirectly supported against each other, extend in a respective separating plane which runs in the axial direction of the axial flux machine (10).

Description

The invention relates to an axial flux machine for a motor vehicle. Furthermore, the invention relates to a method for assembling such an axial flux machine.

The DE 10 2020 122 249 A1 discloses an electrical machine arrangement, comprising an electric machine for driving an electrically powered motor vehicle.

The object of the present invention is to provide an axial flux machine for a motor vehicle and a method for assembling such an axial flux machine, so that a particularly advantageous design of the axial flux machine can be realized.

This problem is solved by an axial flux machine with the features of claim 1 and by a method with the features of claim 8. Advantageous embodiments with expedient further developments of the invention are specified in the remaining claims.

A first aspect of the invention relates to an axial flux machine for a motor vehicle, also referred to simply as a vehicle. This means that the motor vehicle, preferably designed as a motor vehicle, in particular as a passenger car, in its fully manufactured state, has the axial flux machine and can be driven electrically, in particular purely, by means of the axial flux machine. The axial flux machine is also referred to as an electric axial flux machine and is an electric machine. The axial flux machine is also referred to as an axial flux motor (AFM). Preferably, the axial flux machine is a high-voltage component whose electrical voltage, in particular its operating or rated voltage, is preferably greater than 50 volts, in particular greater than 60 volts, and most preferably several hundred volts. The axial flux machine has a stator and two rotors, also referred to as rotor elements, which are non-rotatably connected to a rotor shaft of the axial flux machine common to both rotors, in particular via a radial shaft connection. The respective rotor is thus designed separately from the rotor shaft and non-rotatably connected to the rotor shaft. Thus, the rotors are designed separately from one another, and are connected to each other in a rotationally fixed manner, particularly exclusively, via the rotor shaft. The rotors form, in particular, an overall rotor, which also includes, for example, the rotor shaft. The overall rotor can be driven by means of the stator and is therefore rotatable about a machine axis of rotation relative to the stator. Thus, the rotors and the rotor shaft are rotatable about the machine axis of rotation relative to the stator of the axial flux machine, whose axial direction coincides with the machine axis of rotation. The axial flux machine, whose radial direction is perpendicular to the axial direction of the axial flux machine and thus perpendicular to the machine axis of rotation, also has a housing assembly, wherein the rotors and the rotor shaft, in particular the overall rotor, are rotatable about the machine axis of rotation relative to the housing assembly. In particular, the respective rotor is at least partially arranged in the housing assembly. For example, the rotor shaft is at least partially arranged in the housing assembly. For example, the stator is at least partially arranged in the housing assembly. In particular, it is provided that the stator is designed separately from the housing assembly and is rotationally fixed to the housing assembly. In particular, the stator is connected to the housing in such a way that translational relative movements between the stator and the housing in the axial direction of the axial flux machine are prevented. Preferably, the respective rotor is connected to the rotor shaft in such a way that translational relative movements between the respective rotor and the rotor shaft, which is also simply referred to as the shaft, in the axial direction of the rotor shaft and thus in the axial direction of the axial flux machine are prevented. For example, the axial flux machine can provide drive torques via the rotor shaft for, in particular, purely electric propulsion of the motor vehicle. For example, the respective rotor is designed as a disk, at least in a respective partial area of the respective rotor, so that the respective rotor is designed, for example, as a respective rotor disk.

It is most preferably provided that the stator is arranged at least partially between the rotors in the axial direction of the axial flux machine, whereby at least a part of the stator is arranged between the rotors in the axial direction of the axial flux machine such that, viewed in a first viewing direction parallel to the axial direction of the axial flux machine and extending from the first rotor to a second rotor, a first rotor is at least partially overlapped, i.e., covered, by this part of the stator, and that, viewed in a second viewing direction parallel to the axial direction of the axial flux machine and extending from the second rotor to the first rotor and opposite to the first viewing direction, the second rotor is at least partially overlapped, i.e., covered, by this part of the stator. The axial direction of the axial flux machine, whose circumferential direction runs around the axial direction of the axial flux machine and thus around the machine's axis of rotation, runs Perpendicular to the radial direction of the axial flux machine. When the radial direction is mentioned before and after, this refers, unless otherwise specified, to the radial direction of the axial flux machine. Furthermore, "axial" means the axial direction, and "radial" means the radial direction.

For example, the stator has a through-hole, particularly a central one, into which, viewed in a plane perpendicular to the axial direction, the rotor is arranged at least substantially circularly and/or coaxially with the machine's axis of rotation. The through-hole is, for example, penetrated by the length of the entire rotor, particularly in the axial direction and/or completely. For example, the length is partially formed by the first rotor and partially by the second rotor. Furthermore, the length is, for example, penetrated by the rotor shaft, particularly in the axial direction and/or completely. For example, the rotor shaft is designed as a hollow shaft at least over a length of its length, particularly along its entire axial length.

For example, the housing assembly, in particular an inner circumferential surface of the housing assembly, defines a receiving space, in particular directly, wherein, for example, the respective rotor and/or the rotor shaft and/or the stator is arranged, in particular at least partially, in the receiving space and thus in the housing assembly. The housing assembly forms at least one axial contact surface against which the stator rests in the axial direction, in particular directly, whereby, for example, the stator is positioned axially relative to the housing assembly, which is also simply referred to as the housing. The aforementioned axial contact surface is also referred to as the first axial contact surface. When the contact surface is mentioned above and below, it refers, unless otherwise specified, to the first axial contact surface. For example, the housing assembly has several axial contact surfaces, namely the first contact surface and at least or exactly one further, second contact surface, wherein, for example, the stator rests in the axial direction, in particular directly, against the contact surfaces. Thus, the housing assembly forms the axial contact surfaces.

The housing assembly comprises, in particular, at least or exactly, two separately formed and interconnected housing half-shells, also referred to as half-shell housing parts, whose separating surfaces, via which the housing half-shells are at least indirectly joined and supported against each other, extend in a respective separating plane running in the axial direction. In particular, if the separating surfaces are in direct contact with each other, i.e., directly supported against each other, so that the housing half-shells are then directly joined and directly supported against each other via the separating surfaces, the separating planes coincide. If, for example, the separating surfaces are supported against each other by means of at least or exactly one element formed separately from the housing half-shells and arranged between the separating surfaces, so that the housing half-shells are indirectly joined and supported against each other via the element, the interfaces and thus the separating planes are spaced apart from each other, with the separating planes running parallel to each other. The element can be, for example, a sealing element, which is made of an elastomer, so that, for example, the housing halves are sealed against each other by means of the sealing element. Particularly when the separating surfaces are in direct contact, the separating planes coincide, and preferably the separating planes coincide with the machine's axis of rotation, which thus runs in the respective separating plane. For example, when the separating surfaces are indirectly supported against each other, for example, via the element, the separating planes are spaced apart from each other, in particular such that the respective separating plane is spaced away from the machine's axis of rotation and runs parallel to it. Furthermore, it would be conceivable for the separating surfaces to be in direct contact, in which case the respective separating plane is spaced away from the machine's axis of rotation and runs parallel to it. Since the housing assembly comprises the housing halves, each housing half partially, and in particular half, delimits the receiving space, so that the receiving space is partially, and in particular directly, delimited by the respective housing half. In particular, each housing half-shell thus forms a respective part, specifically a respective half, of the aforementioned inner circumferential surface. The invention enables a particularly advantageous design of the axial flux machine, allowing for particularly simple and therefore time- and cost-effective assembly, i.e., manufacturing. Furthermore, a modular design of the axial flux machine can be implemented, allowing, for example, the easy representation of different power levels. Furthermore, an advantageously small number of parts of the axial flux machine can be represented.

Since the housing assembly, which is also referred to as the housing, comprises at least or exactly two housing halves, the housing assembly is multi-part, in particular two-part. The different power levels can be achieved, in particular, by stacking several stators and several rotors, especially in the axial direction, i.e., arranging them sequentially. In particular, the invention allows for the advantageous creation of a modular system, enabling the different power levels to be represented with a particularly small number of components. Furthermore, a large number of identical components can be implemented, making the different power levels simple and cost-effective to represent.

One of the housing halves is, for example, an upper shell, while the other housing half is, for example, a lower shell. In particular, it is conceivable that, in the installed position of the axial flux machine, which assumes its installed position in the fully manufactured state of the motor vehicle containing the axial flux machine, the housing halves are arranged successively in the vehicle's vertical direction, especially such that the upper shell is positioned higher than the lower shell in the vehicle's vertical direction, and thus the lower shell is positioned lower than the upper shell in the vehicle's vertical direction. The contact surface is also referred to as the housing contact surface and enables simple and precise positioning of the housing, particularly relative to the housing assembly. Furthermore, the multi-part, especially two-part, housing assembly is suitable for advantageous overall integration.

In an advantageous embodiment of the invention, the contact surface is machined by machining, in particular by milling. This allows the stator to be positioned and thus aligned particularly precisely and easily relative to the housing.

To achieve a particularly advantageous design of the axial flux machine, a further embodiment of the invention provides that the stator, which is formed separately from the housing assembly, is screwed to the housing assembly by means of at least one screw element, which is formed separately from both the housing assembly and the stator, and is thereby connected to the housing assembly, in particular such that the stator is rotationally fixed to the housing assembly and preferably such that translational relative movements in the axial direction between the stator and the housing assembly are prevented. This allows the axial flux machine to be assembled and thus manufactured in a particularly time- and cost-effective manner. Furthermore, this enables a particularly advantageous modular design of the axial flux machine.

It has proven particularly advantageous if the screw element is screwed to the corresponding housing assembly from the outside. This allows the stator to be connected to the housing assembly particularly easily, especially by arranging the stator within the housing assembly. For this purpose, for example, a screwing tool is brought into torque-transmitting interaction with the screwing element in the vicinity of the housing assembly, so that the screwing element is screwed in by means of the screwing tool, thereby connecting the stator to the housing.

To enable a particularly simple and rotationally rigid connection of the respective rotor to the rotor shaft, a further embodiment of the invention provides that a respective first length section of the rotor shaft is arranged within a respective second length section of the respective rotor, such that the respective second length section is arranged on the respective first length section. Each length section has a non-circular shape when viewed in a plane perpendicular to the axial direction, specifically such that the respective first length section has a non-circular shape on its outer circumference when viewed in the respective plane, and the respective second length section has a non-circular shape on its inner circumference when viewed in the respective plane. This ensures that the respective rotor is rotationally rigidly connected to the rotor shaft.

Preferably, the respective shape, viewed in the respective plane, is a polygon or polygonal profile. Thus, the aforementioned radial shaft connection, also simply referred to as a shaft connection, which is, for example, a shaft-hub connection, comprises the described non-circular shapes, such as those formed as polygons. Alternatively or additionally, it is conceivable that the respective rotor is rotationally fixed to the rotor shaft via a splined connection, so that, for example, the radial shaft connection also features the splined connection.

To enable particularly time- and cost-effective assembly, i.e., manufacturing, of the axial flux machine, a further embodiment of the invention provides that at least one spacer element, designed separately from the rotors, the stator, and the housing, and for example also referred to as an adjusting disk, is arranged in the axial direction of the axial flux machine between the rotors. This spacer element holds at least the respective sections of the rotors at an axially extending distance from one another. For this purpose, the spacer element can be supported at least indirectly, and in particular directly, on the respective rotor in the axial direction. It is particularly conceivable that a set of adjusting disks is provided to allow the rotors to be adjusted, i.e., positioned, axially relative to one another as required.

In comparison to an axial connection, which, for example, has axial teeth arranged on mutually facing sides and interlocking, and optionally an axial screw connection, the radial shaft connection in the invention has the advantage that such an axial connection or axial toothing does not require further machining or fine-machining for final assembly and the axial final adjustment of the rotors relative to each other; only the contact surface of the housing needs to be machined. This allows for time- and cost-effective assembly and manufacturing of the axial flux machine.

A second aspect of the invention relates to a method for assembling an axial flux machine according to the first aspect of the invention. Advantages and advantageous embodiments of the first aspect of the invention are to be regarded as advantages and advantageous embodiments of the second aspect of the invention, and vice versa.

To achieve a particularly advantageous design and thus a particularly simple, time-saving, and cost-effective assembly of the axial flux machine, one embodiment of the second aspect of the invention provides that, in the first step of the process, the rotors, including any axial adjusting disks between the rotors, are arranged on the rotor shaft and thus pre-assembled by sliding them onto the rotor shaft in the axial direction. In a second step of the process, following the first, the rotor assembly is balanced. In a third step, following the second, the rotor assembly is disassembled by pulling the rotors off the rotor shaft and removing them. In a fourth step, following the third, the rotors, now removed from the rotor shaft, are magnetized. In other words, in the fourth step, the rotors are magnetized while completely removed from the rotor shaft and thus not mounted on it. It is therefore preferably provided that the rotors are not magnetized in the second, first, and third steps of the method. In a fifth step of the method, following the fourth step, the magnetized rotors are arranged on the rotor shaft and thus mounted on it, forming a rotor-stator assembly. This is done, in particular, by sliding the magnetized rotors onto the rotor shaft in the axial direction of the rotor shaft and thus of the axial flux machine, for example, while the stator is also moved in the axial direction of the rotor shaft and thus of the axial flux machine relative to the rotor shaft, thereby positioning the stator between the rotors in the axial direction of the axial flux machine. Furthermore, for example, in a fifth step of the method, the stator is arranged on the rotor shaft, in particular such that the stator is spaced, especially completely, away from the rotor shaft in the radial direction of the rotor shaft and thus of the axial flux machine. In other words, for example, in a fifth step of the process, an inner area of the rotor shaft is arranged in the stator, in particular such that the stator, in particular the entire stator, is spaced away from the rotor shaft in the radial direction of the rotor shaft.

In a sixth step of the process, which follows the fifth step, the housing assembly is mounted by at least indirectly assembling and screwing the housing halves together and thereby connecting them, with the rotor-stator assembly arranged in the housing assembly, i.e., in the receiving space.

To enable particularly time- and cost-effective assembly of the axial flux machine, a further embodiment of the second aspect of the invention provides that, in the fifth step of the method, the rotors and the stator are held at a distance from each other in the axial direction of the axial flux machine by means of a holding device. Alternatively or additionally, in the fifth step of the method, the rotor shaft is held in a fixed position in the axial direction of the axial flux machine by means of a clamping device. In the fifth step of the process, the stator is positioned between the rotors. Alternatively or additionally, in the fifth step, the stator is positioned on the rotor shaft at a distance from the rotor shaft that extends radially in the direction of the axial flux machine. Alternatively or additionally, in the fifth step, the stator is held in a fixed position in the axial direction of the axial flux machine by means of a fixing device. Alternatively or additionally, in a further step of the process following the fifth step and preceding the sixth step, the housing assembly is measured and/or calculated, and in the sixth step, the housing assembly is mounted based on the results of the measurement and/or calculation.

Further advantages, features, and details of the invention will become apparent from the following description of a preferred embodiment and from the drawing. The features and combinations of features mentioned above in the description, as well as those mentioned below in the figure description and/or shown in the figures alone, can be used not only in the combinations specified, but also in other combinations or individually, without departing from the scope of the invention.

• 1 eine schematische Perspektivansicht einer Axialflussmaschine für ein Kraftfahrzeug;
• 2 ausschnittsweise eine schematische Längsschnittansicht der Axialflussmaschine;
• 3 eine schematische und perspektivische Längsschnittansicht der Axialflussmaschine; und
• 4 eine schematische Perspektivansicht eine Rotorwelle der Axialflussmaschine.

The drawing shows in:

• 1 a schematic perspective view of an axial flux machine for a motor vehicle;
• 2 Partially a schematic longitudinal section view of the axial flux machine;
• 3 a schematic and perspective longitudinal section view of the axial flux machine; and
• 4 A schematic perspective view of a rotor shaft of an axial flux machine.

In the figures, identical or functionally equivalent elements are provided with the same reference symbols.

1 Figure 10 shows a schematic perspective view of an axial flux machine 10 for a motor vehicle, also simply referred to as a vehicle. 2 shows the axial flux machine 10 in a schematic longitudinal section view, and 3 Figure 10 shows the axial flux machine in a schematic and perspective longitudinal section view. 1 , 2 until 3 It is evident that the axial flux machine 10 has several, in this case at least or exactly three, stators 12a-c. For example, the stators 12a-c are designed separately from one another and, in particular, are connected to one another indirectly. Furthermore, the axial flux machine 10 has several, in this case at least or exactly four, rotors 14a-d, which are also referred to as rotor elements. The rotor elements are designed separately from one another and separately from the stators 12a-c. The separately designed rotor elements are connected to one another indirectly in a rotationally fixed manner, in particular exclusively. In the embodiment shown in the figures, the rotor elements are connected to one another in a rotationally fixed manner, in particular exclusively, via a rotor shaft 16 of the axial flux machine 10, which is also simply referred to as a shaft and is designed separately from the stators 12a-c and separately from the rotor elements. The rotor elements and the rotor shaft 16 thus form a complete rotor 18, which is rotatable about a machine axis of rotation 20 relative to the stators 12a-c and relative to a housing 22 of the axial flux machine 10. The axial flux machine 10, whose axial direction coincides with the machine axis of rotation 20, thus comprises the housing 22, which, in particular directly, delimits a receiving space 24. The stators 12a-c and the rotors 14a-d are each arranged at least partially, in particular at least predominantly and thus to more than half or completely, in the receiving space 24 and thus in the housing 22. It is evident that the rotor shaft 16 is arranged partly in the receiving space 24 and partly protrudes from the receiving space 24 and thus from the housing 22. It is also evident that the rotor shaft 16 is a shaft common to the rotors 14a-d. Each rotor element is connected to the rotor shaft 16 in a rotationally fixed manner, in particular via a radial shaft connection, and the rotor elements are connected to each other in a rotationally fixed manner, in particular exclusively via the radial shaft connections. In particular, a direct rotationally fixed connection between the rotor elements themselves is not provided.

The complete rotor 18 is rotatably mounted on the housing assembly 22 via at least or exactly two bearings 26 and 28 of the axial flux machine 10, the radial direction of which is perpendicular to the axial direction of the axial flux machine 10 and thus perpendicular to the machine's axis of rotation 20. Each bearing 26, 28 is a rolling bearing, in particular a ball bearing. Each bearing 26, 28 has an inner bearing ring 30, 32 and an outer bearing ring 34, 36. The inner bearing rings 30, 32 and the outer bearing rings 34, 36 are also referred to as bearing rings. Each bearing ring has a raceway. Each bearing 26, 28 also has rolling elements 38, 40. The rolling element 38, 40 is designed as a sphere. For example, the respective inner bearing ring 30, 32 is non-rotatably connected to the rotor shaft 16. In particular, the respective outer bearing ring 34, 36 is non-rotatably connected to the housing assembly 22. Thus, the inner bearing rings 30 and 32 rotate with the rotor shaft 16 about the machine axis of rotation 20 relative to the housing and relative to the outer bearing rings 34 and 36. When the rotor shaft 16 and thus the inner bearing rings 30, 32 rotate about the machine axis of rotation 20 relative to the outer bearing rings 34, 36, the rolling elements 38 roll directly on the raceways of the bearing rings of bearing 26, and the rolling elements 40 roll directly on the raceways of the bearing rings of bearing 28. It is also evident that the stator 12a is arranged in the axial direction of the axial flux machine 10 between the rotors 14a and 14b, the stator 12b is arranged in the axial direction of the axial flux machine 10 between the rotors 14b and 14c, and the stator 12c is arranged in the axial direction of the axial flux machine 10 between the rotors 14c and 14d.

The housing assembly 22 forms axial contact surfaces 42a-f against which the stators 12a-c bear, in particular directly and in the axial direction of the axial flux machine 10. Stator 12a bears directly against the contact surfaces 42a and 42b, which face each other in the axial direction of the axial flux machine 10. Where the axial direction is mentioned above and below, this refers, unless otherwise specified, to the axial direction of the axial flux machine 10. Stator 12b bears in the axial direction, in particular directly, against the contact surfaces 42c and 42d, which face each other in the axial direction. Stator 12c bears in the axial direction, in particular directly, against the contact surfaces 42e and 42f, which face each other in the axial direction. This positions the stators 12a-c in the axial direction relative to each other and relative to the housing assembly 22. In particular, the respective contact surface 42a-f is machined, especially by milling, in order to be able to position the stators 12a-c in the axial direction of the axial flux machine 10 relative to each other and relative to the housing assembly 22.

For example, bearing 26 is a fixed bearing. For example, bearing 28 is an elastically positioned bearing.

For example, rotors 14a and 14b form a first rotor pair. For example, rotors 14b and 14c form a second rotor pair. For example, rotors 14c and 14d form a third rotor pair. It is conceivable that at least one or exactly one spacer element, also referred to as a distance element, is arranged axially between rotors 14a and 14b of the first rotor pair and/or between rotors 14b and 14c of the second rotor pair and/or between rotors 14c and 14d of the third rotor pair, by means of which, for example, the respective rotors 14a-d of the respective rotor pair are held at an axial distance from each other. In the axial direction, an air gap is arranged between each rotor 14a-d and each stator 12a-c, which is limited in the axial direction on one side, particularly directly, by the respective rotor 14a-d and on the other side, particularly directly, by the respective stator 12a-c. The respective air gap can be adjusted, for example, by means of the spacer element. Alternatively or additionally, an air gap between the respective rotors 14a-d of the respective rotor pair can be adjusted, for example, by means of the spacer element.

Out of 4 It is particularly evident that the respective radial shaft connection is a polygon connection. In this case, the rotor shaft 16, over a total length GL, has a non-circular shape on its outer circumference and in a plane perpendicular to the axially extending plane. This shape is a polygon, such as a square or a hexagon. Each portion of the total length GL is also referred to as the first length sections of the rotor shaft 16, so that the rotor shaft 16 exhibits the aforementioned polygon in these first length sections. The respective first length section of the rotor shaft 16 is arranged within a respective second length section of the respective rotor 14a-d, such that the respective second length section of the respective rotor 14a-d is arranged on the respective first length section of the rotor shaft 16. The respective second length section also exhibits the non-circular shape, in this case a polygon, on its inner circumference when viewed in the aforementioned plane. The rotor shaft 16 is inserted into the rotors 14a-d. In other words, the rotors 14a-d are mounted onto the total length GL and thus onto the rotor shaft 16, so that the respective first length section of the rotor shaft 16, in the circumferential direction of the axial flux machine 10 around the machine's axis of rotation 20, positively engages with the respective second length section of the respective rotor 14a-d. This connects the respective rotor 14a-d to the rotor shaft 16 in a rotationally fixed manner, with the rotors 14a-d being connected to each other, for example, exclusively, via the rotor shaft 16 and thus via the respective radial shaft connection. In particular, it is provided that a rotationally fixed connection of the respective rotors 14a-d of the respective rotor pair is achieved via connections facing each other in the axial direction. The end faces of the respective rotors 14a-d of the respective rotor pair are arranged without interlocking gears, i.e., they are omitted. This allows the axial flux machine 10 to be assembled, i.e., manufactured, in a particularly time- and cost-effective manner.

Out of 1 , 2 until 3 It can be seen that the housing assembly 22 has two separately formed and interconnected housing half-shells 44 and 46, which are in 3 shown in a schematic, sectioned, and perspective exploded view. The housing halves 44 and 46 are joined at least indirectly via their parting surfaces 48 and 50 and supported at least indirectly against each other, with the respective parting surface 48, 50 extending in a respective parting plane that runs in the axial direction of the axial flux machine 10. This means that the respective parting plane coincides with the machine's axis of rotation 20, or the respective parting plane is spaced from the machine's axis of rotation 20 and runs parallel to the machine's axis of rotation 20. The respective first length section is in 3 labelled L1, and the respective second length range are in 3 labelled L2.

The following describes a method, also referred to as an assembly method, for assembling, that is, for manufacturing, the axial flux machine 10. The axial flux machine 10 is characterized by its two-part housing assembly 22 and a positive-locking shaft-hub connection, via which the respective rotor 14a-d is positively and rotationally fixedly connected to the rotor shaft 16. The housing (housing assembly 22) is composed of the housing half-shells 44 and 46. For example, the respective housing half-shell 44, 46 is manufactured by a casting process and is thus designed as a single cast component. The respective contact surfaces 42a-f, facing each other in the axial direction, form or define, for example, a respective receptacle for the respective, at least partial, receiving and guiding of the respective stator 12a-c. In particular, the axial distances between the stators 12a-c are determined by the described machining or post-processing of the respective contact surfaces 42a-f. After the stators 12a-c have been arranged in the housing, for example, they are connected to the housing assembly 22 from the outside by screws. The rotors 14a-d are aligned with the stators 12a-c, resulting, for example, in air gaps between the rotors 14a-d and the stators 12a-c.

Out of 3 It is evident that, for example, each stator 12a-c is assigned at least or exactly one screw opening 52 of the housing assembly 22, which is designed, in particular, as a through-opening. The screw opening 52 assigned to each stator 12a-c, which is designed, for example, as a through-opening, is penetrated, for example, by a screw element assigned to each stator 12a-c, which is designed, in particular, as a screw. The respective stator 12a-c is connected to the housing assembly 22 by means of the screw element assigned to it, in particular by being screwed to the housing assembly 22 and thus connected to the housing assembly 22. The respective shaft-hub connection between the rotor shaft 16 and the respective rotor 14a-d is positively engaged by the respective polygon. The polygon, also referred to as a polygon profile, is, for example, a polygon profile P4C. This design is characterized by high torque transmission and longitudinal displacement of the rotor shaft 16 relative to the respective rotor 14a-d, which acts as a hub, particularly under torque and centric load application. Furthermore, the polygonal rotor shaft 16 can be machined economically in a single setup. For example, the bearings 26 and 28 are identical deep groove ball bearings. In this process, the rotors 14a-d are unbalanced and unmagnetized before the process begins. The rotors 14a-d are slid onto the polygonal rotor shaft 16 one after the other, for example, starting with rotor 14a. Axially, i.e., axially extending, distances between the rotors 14a-d are optimally adjusted using the aforementioned spacers, since, for example, the positioning of the stators 12a-c is determined by the contact surfaces 42a-f of the housing, which act as guide surfaces. After the rotors 14a-d are assembled, a sleeve is inserted, for example, as a placeholder for a spacer element between the rotor 14d and the bearing 28, as well as for the bearing 28 itself, and secured with a shaft nut, which is screwed, for example, onto the rotor shaft 16. The assembly thus formed can then be balanced and magnetized. Since the polygon shaft is rotationally symmetrical in four respects, each rotor 14a-d can be subsequently rotated. Such rotation should be prevented by a suitable marking. Furthermore, the rotors 14a-d must not be interchanged when viewed axially. A dowel pin is not required for positioning relative to each other. For mounting the magnetized rotors 14a-d, the polygon shaft is used, for example. Clamped in place. For example, a mounting fixture is provided for all rotors 14a-d and all stators 12a-c. The rotors 14a-d should be held radially from the outside. The four rotors 14a-d and the three stators 12a-c are guided together towards the rotor shaft 16 at relative speeds to each other, so that the air gaps between the stators 12a-c and the rotors 14a-d are always symmetrical. This joint feeding reduces the load on rotors 14b and 14c, for example, because an attractive force acts on both sides. The stators 12a-c are held after reaching their respective end positions so that both bearings 26 and 28 can be mounted. First, the spacer element for bearing 28 is slid on, so that bearing 28b can then be pressed onto the rotor shaft 16. After the inner bearing ring 32 is tightened using the shaft nut, the mounting fixtures for the rotors can be removed. The bearing 26a is then installed. Preferably, no spacer element for adjusting the rotor shaft 16 relative to the housing is provided or required between the bearing 26a and the rotor shaft 16. In particular, the bearing 26a is pressed onto the rotor shaft 16. The inner bearing ring 30 is then tightened, for example, using another shaft nut, which is screwed onto the rotor shaft 16. To mount the two housing halves 44 and 46, they are placed on the stators 12a-c so that all stators 12a-c are in contact with the respective contact surfaces 42a-f. From this point on, the mounting fixtures for the stators 12a-c can be removed, and the housing halves 44 and 46 are assembled. After the housing halves 44 and 46 are screwed together, the stators 12a-c are connected to the housing assembly 22 by screws. Subsequently, for example, a bearing cap 54 can be mounted for the bearing 26. And after inserting a spring, for example, a bearing cap 56 can also be mounted for the bearing 28.

Reference symbol list

10

Axial flux machine

12a-c

stator

14a-d

rotor

16

Rotor shaft

18

Total rotor

20

Machine axis of rotation

22

Housing setup

24

Recording room

26

Storage

28

Storage

30

inner bearing ring

32

inner bearing ring

34

Outer bearing ring

36

Outer bearing ring

38

rolling elements

40

rolling elements

42a-f

Site area

44

Housing half-shell

46

Housing half-shell

48

Separation surface

50

Separation surface

52

Screw opening

54

Bearing cover

56

Bearing cover

GL

Total length range

L1

first length range

L2

second length range

QUOTES INCLUDED IN THE DESCRIPTION

This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions.

Cited patent literature

• DE 10 2020 122 249 A1 [0002]

Claims (10)

Axial flux machine (10) for a motor vehicle, comprising at least one stator (12b), at least two rotors (14b, c) which are non-rotatably connected to a rotor shaft (16) common to the rotors (14b, c) of the axial flux machine (10), and a housing device (22) which forms at least one axial contact surface (42c) against which the stator (12b) rests in the axial direction of the axial flux machine (10), wherein the housing device (22) has two separately formed and interconnected housing half-shells (44, 46) whose separating surfaces (48, 50), via which the housing half-shells (44, 46) are at least indirectly assembled and at least indirectly supported against each other, extend in a respective separating plane which runs in the axial direction of the axial flux machine (10). Axial flux machine (10) according to Claim 1 , characterized in that the mounting surface (42c) is machined. Axial flux machine (10) according to Claim 1 or 2 , characterized in that the stator (12b), which is formed separately from the housing device (22), is screwed to the housing device (222) by means of at least one screw element formed separately from the housing device (22) and separately from the stator (12b), and is thereby connected to the housing device (22). Axial flux machine (10) according to Claim 3 , characterized in that the screw element is screwed in from outside the housing device (22). Axial flux machine (10) according to one of the preceding claims, characterized in that a respective first length region (L1) of the rotor shaft (16) is arranged in a respective second length region (L2) of the respective rotor (14b, c), wherein the respective length region (L1, L2) has a non-circular shape when viewed in a respective plane perpendicular to the axial direction of the axial flux machine (10), whereby the respective rotor (14b, c) is connected to the rotor shaft (16) in a rotationally fixed manner. Axial flux machine (10) according to Claim 5 characterized in that the respective form, when viewed in the respective plane, is a respective polygon. Axial flux machine (10) according to one of the preceding claims, characterized in that at least one spacer element, formed separately from the rotors (14b, c), separately from the stator (12b) and separately from the housing device (22), is arranged in the axial direction of the axial flux machine (10) between the rotors (14b, c), by means of which at least respective partial areas of the rotors (14b, c) are held at a distance from each other in the axial direction of the axial flux machine (10). Method for assembling an axial flux machine (10) according to one of the preceding claims. Procedure according to Claim 8 , characterized in that: - in a first step of the method, the rotors (14b, c) are arranged on the rotor shaft (16) and thereby pre-assembled on the rotor shaft (16) by sliding the rotors (14b, c) onto the rotor shaft (16) in the axial direction of the rotor shaft (16); - in a second step of the method following the first step, the rotor assembly (18) is balanced; - in a third step of the method following the second step, the rotor assembly (18) is disassembled by pulling the rotors (14b, c) off the rotor shaft (16) and removing them; - in a fourth step of the method following the third step, the rotors (14b, c) removed from the rotor shaft (16) are magnetized; - in a fifth step of the method following the fourth step, forming a rotor-stator assembly: ◯ the magnetized rotors (14b, c) are arranged on the rotor shaft (16) and thereby mounted on the rotor shaft (16); and ◯ the rotor shaft (16) is arranged in the stator (12b); and - in a sixth step of the method following the fifth step, the housing assembly (22) is assembled by at least indirectly assembling and screwing together the housing halves (44, 46) and connecting them together while arranging the rotor-stator assembly in the housing assembly (22). Procedure according to Claim 9 , characterized in that: - in the fifth step of the method, the rotors (14b, c) and the stator (12b) are held at a respective distance from each other in the axial direction of the axial flux machine (10) by means of a holding device; and/or - in the fifth step of the method, the rotor shaft (16) is held stationary in the axial direction of the axial flux machine (10) by means of a clamping device; and/or - in the fifth step of the method, the stator is arranged between the rotors (14b, c); and/or - in the fifth step of the method, the stator (12b) is arranged on the rotor shaft (16) at a distance from the rotor shaft (16) extending in the radial direction of the axial flux machine (10); and/or - in the fifth step of the method, the stator (12b) is held in a fixed position in the axial direction of the axial flux machine (10) by means of a fixing device; and/or - in a further step of the method following the fifth step and preceding the sixth step, the housing device (22) is measured and/or calculated, wherein in the sixth step of the method the housing device (22) is mounted depending on a result of the measurement and/or calculation.