WO2023208834A1

WO2023208834A1 - Assembly for an electric machine, and method for producing an assembly for an electric machine

Info

Publication number: WO2023208834A1
Application number: PCT/EP2023/060634
Authority: WO
Inventors: Shkelzen Bekteshi; Benedikt Streck
Original assignee: Rolls-Royce Deutschland Ltd & Co Kg
Priority date: 2022-04-25
Filing date: 2023-04-24
Publication date: 2023-11-02

Abstract

The invention relates to an assembly for an electric machine. The assembly comprises a coil winding (8) with a plurality of coil turns (801) and stator poles (7) of a stator, said stator poles being arranged in at least two paired rows (71-1, 71-2; 71-3, 71-4) which are mutually spaced, wherein each pair of rows (71-1, 71-2; 71-3, 71-4) define a winding area (80, 80-1, 80-2) between the rows for receiving the coil winding (8) or a section (802, 803) of the coil winding (8), and each stator pole (7) has a first end (73) and a second end (72). The assembly additionally comprises axially spaced, non-magnetic and non-magnetizable first and second holding plate (94, 93), said stator poles (71) extending between the holding plate (94, 93). According to the invention, all of the stator poles (71) of at least one of the rows (71- 1, 71- 3) are encapsulated with an injection-molding material at the first ends (73) thereof, said injection-molding material forming the first holding plate (94). The invention additionally relates to methods for producing an assembly for an electric machine.

Description

Assembly for an electrical machine and method for producing an assembly for an electrical machine

Description

The invention relates to an assembly for an electrical machine, an electrical machine with such an assembly and methods for producing an assembly for an electrical machine.

A transverse flux machine is a rotating electrical machine in which a relevant magnetic flux is essentially transverse or perpendicular to an axis of rotation of at least one rotor of the transverse flux machine. The stator winding is designed as a circumferential winding that is arranged concentrically to the axis of rotation of the rotor. The transverse flux machine is often designed as a permanently excited synchronous machine and can be designed to be supplied with a single-phase or multi-phase alternating voltage. The design of the transverse flux machine allows magnetic and electrical circuits to be constructed largely independently of each other.

It is known that the stator of a transverse flux machine or other rotating electrical machine has a plurality of stator poles (also called stator yokes or referred to as iron cores). The problem arises as to how these can be provided and arranged in an efficient manner.

The present invention is based on the object of providing an assembly for an electrical machine which includes stator poles which are provided in an effective manner. Furthermore, efficient methods for producing an assembly with stator poles should be provided.

This object is achieved by an assembly with the features of claim 1, an electrical machine with the features of claim 9, a method with the features of claim 11 and a method with the features of claim 16. Embodiments of the invention are specified in the dependent claims.

The present invention then considers, in a first aspect of the invention, an assembly for an electrical machine, for example a transverse flux machine, which has a coil winding with a plurality of coil turns and stator poles of a stator, the stator poles being arranged in at least two mutually assigned and spaced rows. Two rows assigned to each other define a winding space between them for receiving the coil winding or a section of the coil winding. Each stator pole has a first end and a second end. The assembly further includes axially spaced, non-magnetic and non-magnetizable first and second holding plates, with the stator poles extending between the holding plates.

It is provided that all stator poles of at least one of the rows are encapsulated at their first ends with an injection molding material which forms the first holding plate.

Accordingly, one aspect of the present invention is based on the idea of connecting or integrating the one ends of the stator poles of at least one row with the first holding plate via an injection molding process, the first holding plate being produced by the injection molding process. In this way, one end of all the stator poles are connected to the first holding plate at the same time, without the need for complex individual assembly of the individual stator poles on the first holding plate. By overmolding the ends of the stator poles with injection molding material, a secure and stable positive connection of the stator poles to the holding plate is also provided. The formation of separate structures on the stator poles for provision For example, adhesive surfaces or other connecting elements are not required, which contributes to a cost reduction.

A further advantage associated with the solution according to the invention is that the stator poles are connected to the holding plate during production, so that a separate process step for producing the holding plate is not necessary.

The present invention thus enables the stator poles to be connected to an associated holding plate in a safe and simple manner in just a few process steps.

One embodiment of the invention provides that all stator poles of at least one assigned row are encapsulated at their second ends with an injection molding material which forms the second holding plate. The solution according to the invention is therefore used in the same way with regard to those rows of stator poles that are connected to the second holding plate. It also applies to these rows that they are encapsulated with the second holding plate using injection molding technology. In this way, the stator poles connected to the second holding plate can be efficiently connected to the second holding plate in one work step and at the same time safely and reliably. This embodiment of the invention provides that of two mutually assigned rows of stator poles, which form a winding space between them, one row is connected to the first holding plate via an injection molding process and the other row is connected to the second holding plate via an injection molding process.

It should be noted that the term “winding space” in the sense of the present invention is to be understood as meaning that it does not necessarily designate the entire winding space of a coil winding, but can also designate partial winding spaces that are composed of an overall winding space.

It is further pointed out that the winding wire, which forms the individual coil turns and the coil winding as a whole, is provided with insulation in a manner known per se. The thickness of the insulation ensures the required insulation distances. The winding wire is, for example, a rectangular conductor or round conductor provided with winding insulation. Examples of materials that can be used for the winding wire are copper and aluminum. Furthermore, a nickel protective layer can be used, which prevents conductor corrosion, in particular oxidation. A further embodiment of the invention provides that the coil winding is fixed in sections in the winding space by spaced-apart elements made of fixation material, the elements made of fixation material holding the coil turns and each being supported on the stator poles of at least one of the rows that delimit the winding space. It can be provided that the elements made of fixation material are designed in the shape of a disk as fixation disks. This configuration effectively allows the coil winding to be arranged and fixed in the winding space.

A further embodiment provides for the provision of winding spaces or partial winding spaces through two rows of bent stator poles arranged offset from one another.

In a further embodiment it is provided that the stator poles are each curved, with the two rows of stator poles assigned to one another being radially spaced apart, the radial direction relating to the axis of rotation of an electrical machine in which the assembly can be arranged, and the stator poles the radially inner row are bent concavely when viewed from the radially outside and the stator poles of the radially outer row are bent convexly when viewed from the radially outside, so that their mutually facing sections together define the winding space, wherein they define the winding space transversely to a circumferential direction along which the Stator winding extends, limit.

It can be provided that the stator poles of all rows are designed in an identical manner and the stator poles of two rows assigned to one another are arranged in reverse orientation in the two rows.

One embodiment provides that the stator poles have a straight middle section and two sections angled therefrom, each of which forms one end of the stator poles. The stator poles are bent in a C shape, for example.

A further embodiment provides that the stator poles are arranged in at least four circumferential rows, with two of the circumferential rows being assigned to each other and forming a partial winding space, the partial winding spaces extending radially spaced apart in the circumferential direction, and in the partial winding spaces Sections of the coil winding that extend longitudinally in the circumferential direction are arranged (which are bent or returned by 180 ° at the circumferential ends of the coil windings).

A further embodiment provides that the stator poles are each aligned radially and have radially aligned side surfaces spaced apart in the circumferential direction. In this way, effective convection cooling of the stator poles is possible across both side surfaces.

A further embodiment provides that both ends of the stator poles are each arranged in one of the holding plates. As explained, the stator poles are firmly connected at one end to one of the holding plates using an injection molding process. At their other end they are simply inserted into corresponding recesses in the holding plates. The ends of the stator poles can also be referred to as pole heads.

According to a further aspect of the invention, the present invention relates to an electric machine comprising: a rotor provided with permanent magnets, having an axis of rotation defining an axial direction, a radial direction and a circumferential direction, a stator having, as active components, stator poles and a coil winding comprises, wherein the stator is designed as a ring structure with a plurality of ribs which adjoin one another in the circumferential direction, the active components of the stator are formed by assemblies according to claim 1, and the assemblies are held and positioned by the ribs of the ring structure.

One embodiment provides that the rotor comprises axially spaced outer walls, each of which has or integrates permanent magnets, with the assemblies each protruding radially into a volume between the axially spaced outer walls of a rotor. It is provided that the rotor and the stator form an air gap that extends in the radial direction and runs around the circumference (with an air gap normal vector pointing in the axial direction).

In a further aspect of the invention, the present invention relates to a method for producing an assembly of an electrical machine, the assembly having: a coil winding with a plurality of coil turns, Stator poles of a stator, which are arranged in at least two mutually assigned and spaced rows, with two mutually assigned rows defining a winding space between them for receiving the coil winding or a section of the coil winding, and wherein each stator pole has a first end and a second end , axially spaced, non-magnetic and non-magnetizable first and second holding plates, the stator poles extending between the holding plates.

The method includes the step of connecting all stator poles of at least one row at their first ends to the first holding plate as part of an injection molding process in which the first holding plate is produced.

The method according to the invention provides for one end of the stator poles of at least one row to be positively connected to the first holding plate via an injection molding process, the first holding plate being produced by the injection molding process. The method according to the invention allows the stator poles to be connected to an associated holding plate safely and easily in just a few process steps.

One embodiment of this provides that all stator poles of at least one assigned row are connected in a corresponding manner at their second ends to the second holding plate as part of an injection molding process in which the second holding plate is produced. Thereafter, of two mutually assigned rows of stator poles, which form a winding space between them, one row is connected to the first holding plate via an injection molding process and the other row is connected to the second holding plate via an injection molding process.

A further embodiment provides that the coil winding is arranged on the stator poles connected to the first holding plate or to the second holding plate before the winding space is formed to accommodate the coil winding. In this way, easy assembly of the coil winding is possible.

A further embodiment provides that the stator poles are arranged in four rows, with two of the rows being assigned to each other and forming a partial winding space, with the partial winding spaces extending radially spaced apart in the circumferential direction, and in each of the partial winding spaces Sections of the coil winding extending in the circumferential direction are arranged. In this embodiment, the process includes the steps: Connecting all stator poles of two of the rows at their first ends to the first holding plate as part of an injection molding process,

Connecting all stator poles of the other two rows at their second ends to the second holding plate as part of an injection molding process,

Arranging two sections of the coil winding on the two rows of stator poles connected to the first holding plate or to the second holding plate,

Arrangement of the two holding plates parallel to one another in such a way that the stator poles of the respective holding plate extend in the direction of the other holding plate and thereby form two partial winding spaces between them, each of which accommodates one of the two sections of the coil winding.

Accordingly, two rows of stator poles are connected to the first holding plate and two associated rows of stator poles are connected to the second holding plate. After attaching the coil winding, the holding plates are arranged in parallel, with two assigned rows forming a partial winding space between them in which the coil winding runs.

In a further aspect of the invention, the present invention relates to a method for producing an assembly of an electrical machine, the assembly having: a coil winding with a plurality of coil turns,

Stator poles of a stator, which are arranged in at least two mutually assigned and spaced rows, with two mutually assigned rows defining a winding space between them for receiving the coil winding or a section of the coil winding, and wherein each stator pole has a first end and a second end , axially spaced, non-magnetic and non-magnetizable first and second holding plates, the stator poles extending between the holding plates.

The procedure includes the steps:

Connecting all stator poles of at least one row at their first ends to the first holding plate,

Connecting all stator poles of at least one assigned row at their second ends to the second holding plate,

Arranging the coil winding on the stator poles connected to the first holding plate or to the second holding plate,

Arrangement of the two holding plates parallel to one another in such a way that the stator poles of the respective holding plate extend in the direction of the other holding plate and thereby Two rows assigned to each other form a winding space between them for the coil winding.

This aspect of the invention is based on the idea of connecting the stator poles of one row or some of the rows to the first holding plate and connecting the stator poles of another row or some of the other rows to the second holding plate. In principle, this connection can be made in any manner and sequence. The coil winding is then arranged on the stator poles connected to the first holding plate or to the second holding plate. Only then are the holding plates arranged parallel to one another, with the respective stator poles extending in the direction of the other holding plate and forming at least one winding space for the coil winding, with two assigned rows each forming a winding space or partial winding space.

Due to the fact that the stator poles of one row or some of the rows are connected to the first holding plate and the stator poles of another row or some of the other rows are connected to the second holding plate, the coil winding can be arranged on the stator poles before the winding spaces are created. This allows for easy and effective assembly of the coil winding.

One embodiment of this provides that all stator poles in a row are simultaneously connected to the associated holding plate in order to simplify the manufacturing process. This can be done, for example, by connecting the stator poles of the at least one row at their first end to the first holding plate as part of an injection molding process in which the first holding plate is produced and / or by connecting the stator poles of the at least one associated row at their second end be connected to the second holding plate as part of an injection molding process in which the second holding plate is produced.

A further embodiment of the method provides that both ends of the stator poles are each arranged in one of the holding plates, with the stator poles being firmly connected to one of the holding plates at one end and being inserted into corresponding recesses in the other of the holding plates at their other end.

The invention is explained in more detail below with reference to the figures of the drawing using several exemplary embodiments. Show it: Figure 1 is a partially sectioned view of an exemplary embodiment of an electric drive unit, which comprises a motor unit, a bearing unit and a coupling unit, the motor unit being designed as a transverse flux machine with an external rotor;

Figure 2 shows the motor unit and the clutch unit of the electric drive unit of Figure 1 in a partially sectioned perspective view;

Figure 3 shows the electric drive unit of Figure 1 in a partially sectioned perspective view;

Figure 4 is a perspective view of the top of the electric drive unit of Figure 1;

Figure 5 is a perspective view of the underside of the electric drive unit of Figure 1;

Figure 6 schematically shows an exemplary embodiment of an electric drive unit, which comprises a transverse flux machine with an external rotor and a bearing unit corresponding to Figures 1 to 5, the transverse flux machine having two rotor-stator assemblies which are arranged one behind the other in the axial direction and are firmly connected to one another;

Figure 7 is a perspective, partially sectioned view of an embodiment of an assembly secured to ribs of the stator, the assembly including axially spaced first and second retaining plates, stator poles extending between the retaining plates, and a circumferentially extending coil winding;

Figure 8 shows the assembly of Figure 7 in a perspective view;

Figure 9 is a sectional view of the assembly of Figures 7 and 8;

Figure 10 shows the arrangement of two rows of stator poles on the first holding plate

Assembly of Figures 7-9 in a perspective view and in a view from above; Figure 11 shows the arrangement according to Figure 10 together with a coil winding which is supported on the stator poles of the two rows, in a perspective view and in a view from above;

Figure 12 shows the arrangement of two further rows of stator poles on a second holding plate of the assembly of Figures 7-9 in a perspective view and in a view from below;

13 shows the assembly after the arrangement according to FIG. 10 with two rows of stator poles and the arrangement according to FIG form a partial winding space for the coil winding;

Figure 14 schematically shows a tool of an injection molding device for receiving the stator poles and for producing the first holding plate;

Figure 15 shows the closed tool corresponding to Figure 14;

Figure 16 shows a flow chart of a method for producing an assembly corresponding to Figures 10-13; and

Figure 17 is a flow chart of a further method for producing an assembly corresponding to Figures 10-13.

Figures 1 to 5 show different views of an exemplary embodiment of an electric drive unit. The electric drive unit comprises an electric motor unit 1, a bearing unit 2 with an output shaft 21 and a static bearing part 22 and a coupling unit 3. The three units 1, 2, 3 represent modular units that can be manufactured separately and can be connected to one another via defined mechanical interfaces , as will be explained later. The description of the first exemplary embodiment refers to all of Figures 1 to 5, unless specific reference is made to specific figures. The electric motor unit 1 comprises a rotor 11 and a stator 12. In the exemplary embodiment shown, the motor unit 1 is designed as a transverse flux machine, in which the rotor 11 is designed as an external rotor 11. Such motor units 1 are also referred to as transverse flux motors.

The rotor 11 has two axially spaced outer walls 111, 112, each of which has or integrates permanent magnets (not shown separately) aligned in the radial direction. The two outer walls 111, 112 are connected to one another by a radially outer, front wall 113. The stator 12 is formed by a ring structure with a plurality of ribs 120 which adjoin one another in the circumferential direction and which each form a cooling air channel 121 between them. The individual ribs 121 hold the active components of the stator 12, which are arranged in the volume 122 defined by the outer walls 111, 112 and the front wall 113 of the rotor 11. The active components of the stator are, in particular, stator poles (also referred to as stator yokes or iron cores) and coil windings, as will be explained later. In this case, several circumferential windings are realized in the stator 12, which are arranged at the same distance from the central axis of symmetry of the drive unit in the circumferential direction.

In such a configuration as a transverse flux motor, an air gap 131 runs between the rotor 11 and the stator 12 (namely the air gap 131 between the permanent magnets of the rotor 11 and the active components of the stator 12) in such a way that the air gap 131 extends in the radial direction and thereby rotates in the circumferential direction of the electric motor 1. In the construction described, two air gaps are provided, each on the inside adjacent to the outer walls 111, 112.

The rotor 11 and the stator 12 are connected to one another via an axially front bearing 141 and an axially rear bearing 142, so that the rotor 11 can rotate around the stator 12.

In alternative embodiments, the motor unit 1 can have a plurality of rotor-stator assemblies of the type described, which are arranged one behind the other in the axial direction and are firmly connected to one another.

The bearing unit 2 includes the output shaft 21 and the static bearing part 22. The output shaft 21 has a rotation and longitudinal axis (not shown separately) which is identical to the axis of symmetry of the overall arrangement, the rotation and longitudinal axis defining the axial direction of the drive unit. The static bearing part 22 serves to support the output shaft 21. For this purpose, the bearing unit 2 comprises an axially front bearing 24 and an axially rear bearing 25. The bearings 24, 25 can be designed in such a way that a certain axial play of the output shaft 21 is permitted.

The static bearing part 22 has a plurality of ribs or stiffeners 27 which are arranged in the circumferential direction. The static bearing part 22 further comprises a basic structure extending in the radial direction, for example a base plate 260, which has a mechanical interface 26 on its radially outer region for connecting the bearing unit 2 and thus the entire drive unit with a static structure, for example the airframe of an aircraft. can train. Instead of a base plate 260, the basic structure can be formed, for example, by several interconnected, radially extending arms.

The rotationally symmetrical output shaft 21 includes an axially front end 211, which is coupled to a shaft journal 32 of the coupling unit 3 and is driven by the electric motor unit 1, as will be explained. The shaft journal 32 can be formed in one piece with the coupling unit 3. The output shaft 21 further comprises an axially rear end 212, which forms an interface 23 for connection to a load to be driven. For example, a propeller can be connected as a load to the output shaft 21 via the interface 23. The interface 23 includes, for example, openings 231 for realizing screw connections or bolt connections. The output shaft 21 widens conically between the axially front end 211 and the axially rear end 212. The axial length of the output shaft 21 is greater than the axial height of the motor unit 1 and clutch unit 3, so that the output shaft 21 protrudes axially relative to the latter.

However, this is only to be understood as an example. Depending on the choice of bearing and application, the output shaft 21 can also have a shape other than a conical one. Alternatively, it can also be provided that the axial length of the output shaft 21 does not exceed the axial height of the motor unit 1.

The output shaft 21 is pre-assembled in the static bearing part 22, so that the output shaft 21 and bearing part 22 together form the modular bearing unit 2.

The coupling unit 3 serves to transmit the torque of the rotor 11 of the motor unit 1 to the output shaft 21. The rotor 11 is radial to the output shaft 21 spaced. Accordingly, the clutch unit 3 has clutch means which extend in the radial direction between the rotor 11 and the output shaft 21.

In the exemplary embodiment shown, these coupling means are provided by a clutch disk 31, although this is not necessarily the case. For example, the coupling means can alternatively be formed by a plurality of radially extending and circumferentially spaced struts or spokes, similar to a bicycle hub, or by a diaphragm coupling.

The clutch disk 31 is coupled radially on the outside to the rotor 11 and radially on the inside with the output shaft 21. The coupling of the clutch disk 31 with the rotor 11 takes place via a predefined mechanical interface 42, which includes bolts 421 which connect the radially outer edge 312 (see FIG. 2) of the clutch disk 31 to the axially front wall 112 of the rotor 11 in a rotationally fixed manner.

The clutch disk 31 is coupled to the output shaft 21 via the already mentioned shaft journal 32. The radially inner edge 311 (see FIG. 2) of the clutch disk 31, which has a central recess, is connected to the shaft journal via a mechanical interface 43, which includes bolts 431 32 connected in a rotationally fixed manner. The shaft journal 32 includes an axially projecting region 321, which projects into the axially front end 211 of the output shaft 21 and transmits a torque to the output shaft 21 due to a positive connection between the shaft journal 32 and the axially front end 211 of the output shaft 21. In addition, a mechanical connection 44 with bolts 441 can be provided for a rotationally fixed connection between the shaft journal 32 and the axially front end 211 of the output shaft 21. The shaft journal 32 can alternatively be integrated into the clutch disk 31.

Alternatively, the clutch disk 31 is connected directly to the output shaft 21, without the interposition of a shaft journal 32.

To connect the motor unit 1 and the bearing unit 2, a mechanical interface 41 is provided, which connects the motor unit 1 to the base plate 260 of the bearing unit 1 by means of bolts 411 or the like (see Figure 2). For this purpose, the stator has a holding plate 15, which forms, on the one hand, a flange 151 for connection to the stator 12 and, on the other hand, a flange 152 for connection to the base plate 260, as can be seen in particular from FIG. In some embodiments this can be the case Holding plate 15 can be designed to be flexible in order to improve the dynamic behavior of the drive unit.

By using a clutch unit 3 with a clutch disk 31, a torque transmission from the rotor 11 to the output shaft 21 can be realized, which on the one hand has a high torsional rigidity and on the other hand with regard to lateral forces, axial forces and / or bending forces that come from a load connected to the output shaft 21 are introduced into the electric drive unit, has a low rigidity, so that introduced forces such as imbalances can be absorbed by the coupling unit 3, so that the rotor 11 is decoupled from such forces and the precision and symmetry of the air gap 131 between the rotor 11 and the stator 12 is not or only slightly influenced by such forces.

Figures 4 and 5 show a perspective view of the complete drive unit consisting of motor unit 1, bearing unit 2 and coupling unit 3. Reinforcing ribs 27 of the bearing unit 2, which are spaced apart in the circumferential direction perpendicularly on the base plate 260, can be clearly seen in Figure 4 . In the view obliquely from below in Figure 5, the clutch disk 31 can be seen, which is connected to the rotor 11 at its radially outer edge 312 or to the shaft journal 32 at its radially inner edge 311.

Figures 6 to 9 show exemplary embodiments of the invention, which are fundamentally based on the exemplary embodiment of Figures 1 to 5 and in which the active components of the stator 12 and their arrangement are shown in more detail.

6 shows an electric drive unit with a motor unit 1 designed as a transverse flux machine with a rotor 11 and stator 12 and with a bearing unit 2, which includes an axially arranged, rotatable output shaft 21 and a static bearing part 22 which supports the output shaft 21. The coupling unit 3 explained in Figures 1 to 5 is not shown in Figure 6, but is included in a corresponding manner. The reference numerals contained in FIG. 6 generally designate the same parts as explained with reference to FIGS. 1 to 5, provided that no differences arise from the following description. This applies in particular to the design of the stator 12 as a ring structure with a plurality of ribs 120 which adjoin one another in the circumferential direction and which each form a cooling air channel 121 between them. Figure 6 also shows the axis of rotation 110 of the rotor 11, which is equal to the axis of rotation of the output shaft 21 and represents the axis of symmetry of the construction. The axis of rotation 110 defines an axial direction x, a radial direction r and a circumferential direction.

A difference from Figures 1 to 5 results from the fact that the motor unit 1 of Figure 6 comprises two rotor-stator assemblies 1110, 1120, which are arranged one behind the other in the axial direction and are firmly connected to one another. Accordingly, the rotor 11 comprises three axially spaced outer walls 111, 112, 114, each of which has or integrates permanent magnets 5, as well as two frontal, radially outer walls 113, 115. The outer walls 111, 112, 114 and the frontal walls 113, 115 form this two axially spaced volumes 122 of the two rotor-stator assemblies 1110, 1120, each containing the active components of the stator 12 of the respective assembly, according to the description of the volume 122 in Figure 1.

It should be noted that the active components of the stator 12 are held and positioned by the ribs 120. For this purpose, the ribs 120 have holding projections 123, to which a functional assembly explained with reference to FIGS. 7 to 14 is attached, which projects into the volume 122 (separately for each rotor-stator assembly 1110, 1120).

The permanent magnets 5 of the rotor are only shown on the right side of Figure 6 for better clarity. They are arranged on the inside of the outer walls 111, 112, 114. The air gap 131 shown in FIG. 1 runs between them and the assigned stator poles of the functional assembly mentioned.

Another difference between FIG. 6 and FIGS. The general rule is that the transverse flux machine has a first end 1010 facing a load to be driven and a second end 1020 facing away from the load to be driven. In Figure 6, it forms openings 101 at its first end 1010, which enable an air flow 60 to enter the motor unit in an initially primarily axial orientation. This can be supported by a fan 91, which is, however, optional. For example, the air flow comes from a propeller that is driven by the output shaft 21. The second end 1020 facing away from the load to be driven is sealed airtight to prevent incoming air from immediately leaving the motor unit in the axial direction. For this purpose, a cover plate 102 is provided, which is shown schematically. The cover plate 102 is connected to the stator 12 in FIG. 6, but could alternatively be connected to the rotor 11 (or, depending on the design, even be formed by a clutch disk 31 according to FIGS. 1 to 5).

This ensures that the incoming air flow 60 flows radially outwards as an air flow 61 through the cooling air channels 121 and the active components of the stator arranged in the volume 122. The radial air flow 61 can also be optionally supported by fans 92.

It should be noted that the front walls 113, 115 of the rotor 11 are provided with radial openings 116, which enable the cooling air flow 61 to be directed into the environment.

Alternatively, it can be provided that openings in the motor unit are formed at the second end 1020 facing away from the load to be driven, while the first end 1010 facing the load to be driven is sealed in an airtight manner in this case. For this purpose, the openings 101 are closed by structures. A further alternative provides that a cooling flow is provided which extends radially inwards through the stator 12. For this purpose, it is provided that an air flow on the outer circumference of the rotor, which comes from a propeller, for example, is deflected via baffles and directed through the openings 116 in the walls 113, 115 of the rotor 11 into the stator 12 and from radially outside to radially inside the active components of the stator arranged in the volume 122 and the cooling air channels 121 flows.

Figures 7 to 9 show in greater detail, using exemplary embodiments, the active components of the stator, which are each arranged in the volume 122 of Figure 6. For this purpose, the stator according to FIG. 7 comprises an assembly 9, which can represent a modular, prefabricated component. The assembly 9 extends in the radial direction r and in the circumferential direction cp. It comprises two axially spaced, non-magnetic and non-magnetizable holding plates 93, 94. These have radially inner

Fastening areas 930, 940 on which the holding plates 93, 94 are connected to a plurality of the ribs 120 of the stator 12. This is done, for example, via the holding projections 123 of the ribs 120, see Figure 6. Stator poles 71 extend between the holding plates 93, 94, the entirety of which provides an iron core structure 7 of the stator. The stator poles 71 define a circumferentially extending winding space 80, in which a circumferentially extending coil winding 8 is arranged. It is provided that an air flow flowing through the cooling air channels 121 (see Figure 6) flows radially through the assemblies 9 in the area between the two holding plates 93, 94 and flows past the stator poles 71 and the coil winding 8.

The stator poles 71 are each aligned radially. They each have two radially aligned, circumferentially spaced side surfaces 710, 720, both of which are cooled by a cooling air flow.

The coil winding 8 consists of individual coil turns 801 (see Figure 8), which merge into one another and are formed by a continuous winding wire. The coil winding 8 includes two axially spaced winding packages 81, 82 in a partial winding space 80-1 and two axially spaced winding packages 83, 84 in a partial winding space 80-2, the winding packages 81-84 each having sections extending longitudinally in the circumferential direction the coil winding 8 represent. As can be seen in Figure 8, the winding packages 81-84 form a coil winding 8, with Figure 8 additionally showing a deflected section 85 of the coil winding 8, which connects the winding packages 81-84. A corresponding deflected section can be found at the other end of the coil winding 8.

Two of the winding packages 81, 82 and 83, 84 are spaced apart in the axial direction both from each other and from the holding plates 93, 94, so that cooling air can flow around them on their top and bottom. This is illustrated in FIG. 9. The assembly 9 then forms three radially extending and axially spaced cooling air flow channels 67, 68, 69 for cooling the winding packages 81, 82 and 83, 84, with a cooling air flow channel 67 running adjacent to the upper holding plate 93, a cooling air flow channel 68 runs in the area between the winding packages 81, 83 and 82, 84 and a cooling air flow channel 69 runs adjacent to the lower holding plate 94. The division of the winding into axially spaced winding packages 81-84 increases the coolable surface of the winding. In other embodiment variants, more than two axially spaced winding packages can also be provided. Alternatively, axially spaced winding packages 81, 82 and 83, 84 can be dispensed with, so that only one winding package is arranged in each partial winding space 80-1, 80-2. 7 and 9, two winding packages 81, 82 and 83, 84 can each be fixed in the winding space 80-1, 80-2 by a fixation material 86, although the fixation material only extends slightly in the circumferential direction (and is therefore disk-shaped or is plate-shaped) in order not to impair cooling by the cooling air flow.

It should be noted that in order to avoid physical contact of the coil winding 8 with the stator poles 71, a mechanical protective layer can additionally be applied to the stator poles 71 on the side facing the winding space 80-1, 80-2, for example an aramid paper analogous to the use of Groove papers in the groove of radial flow machines.

Referring again to FIG. 7, a special arrangement of the stator poles 71 is provided to realize the partial winding spaces 80-1, 80-2. The stator poles 71 are arranged in four circumferential rows 71-1, 71-2, 71-3, 71-4, with two of the circumferential rows 71-1, 71-2 and 71-3, 71-4 being assigned to each other and form a partial winding space 80-1, 80-2. It is further provided that the stator poles 71 of two mutually assigned circumferential rows 71-1, 71-2 and 71-3, 71-4 are each arranged offset from one another in the circumferential direction.

The stator poles 71 are also bent. For example, they are bent in a C shape. The stator poles 71 of each radially inner circumferential row 71-1, 71-3 are bent concavely when viewed from the radial outside and the stator poles 71 of each of the radially outer circumferential rows 71-2, 71-4 are bent convexly when viewed from the radially outside, so that their Mutually facing sections together define the partial winding spaces 80-1, 80-2. The stator poles 71 of each two rows delimit the partial winding spaces transversely to the circumferential direction. For this purpose, the stator poles 71 are arranged in the opposite orientation in the mutually assigned circumferential rows 71-1, 71-2 and 71-3, 71-4.

It is further provided that the ends 72, 73 of the stator poles 71 form pole heads (upper pole heads and lower pole heads). The ends 72, 73 adjoin the permanent magnets 5 of FIG. 8 and are separated from them only by an air gap (corresponding to the air gap 131 of FIG. 1). For this purpose, it is provided that the ends 72, 73 or pole heads are each arranged in one of the holding plates 93, 94 and flush with their outer sides 931, 941 complete. Accordingly, in Figures 7 to 9, the upper ends 72 of the stator poles 71 can be seen in the plane of the outside 931 of the upper holding plate 93.

In each rotor-stator assembly 1110, 1120 of Figure 6, several assemblies 9 are provided, which connect to one another in the circumferential direction. For example, three assemblies 9 are provided for each rotor-stator assembly 1110, 1120, with the coil winding of one assembly each being supplied with one phase of a three-phase alternating voltage.

The stator poles 71 can be formed, for example, by laminated metal sheets.

The manufacturing process with which the stator poles 71 are connected to the holding plates 93, 94 to form winding spaces is explained below with reference to FIGS. 10 to 17.

According to Figure 10, two rows of stator poles 71 are first firmly connected to one holding plate 94 via an injection molding process and integrated into it. The holding plate 94 is the axially rear holding plate in relation to the electrical machine of Figures 1-6. It is also referred to below as the first holding plate or lower holding plate.

The stator poles of rows 71-1 and 71-3 are connected to the first holding plate 94. This is done using an injection molding process in which the first holding plate 94 is formed in one step and at the same time one end of the stator poles 71 is connected to the holding plate 94. The corresponding injection molding process is shown schematically in Figures 14 and 15. According to the upper half of Figure 14, the stator poles 71 are arranged in two rows 71-1, 71-3. The stator poles 71 have an approximately C-shaped configuration, having a straight middle section 715 and two sections 716, 717 angled therefrom. The unwound sections 716, 717 form the two ends 72, 73 of the stator poles.

The stator poles 71 are inserted into a die 910 of an injection molding device. The die 110 forms the negative of the outer shape for the first holding plate 94. It has recesses 911 in areas that accommodate one end 73 of the stator poles 71 and elevations 912 in areas that form recesses 95 in the holding plate 94 after production . This can be seen further in Figure 15. Figure 15 shows the stator poles 71 as they are arranged in the recesses 911 of the die 910. The ends 73 of the angled, oblique sections 717 protrude into the corresponding recesses 911 of the die 910. In principle, a different course of the ends 73 of the stator poles 71 can also be provided. However, they do not just run perpendicular to the holding plate 94, since in such a case no positive connection would occur when overmolding with injection molding material.

A cover 915 is placed on the die 910 for the injection molding process. So that the injected plastic cannot penetrate between the sections 717, 716 of the stator poles 71 in the areas The plastic can then be injected. The ends 73 of the stator poles 71 are positively molded with the injection molding material, which at the same time forms the first holding plate 94 (which is shown in FIG. 15).

In Figure 14 below, the finished first holding plate 94 with the integrated ends 73 of the stator poles 71 is shown in a perspective view from below. The two rows 71-1, 71-3 of stator poles 71 are firmly connected to the holding plate 94. The ends 73 are flush with the outside 941 of the first holding plate 94. They are overmolded with the injection molding material of the first holding plate 94.

Furthermore, two rows 95-2, 95-4 of recesses 95 can be seen, which serve to accommodate one end of the other two rows 71-2, 71-4 of stator poles 71, with these one ends being inserted into the first holding plate 94 . The stator poles 71 of the rows 71-2, 71-4 are firmly connected at their other ends to the other holding plate 93, as is explained with reference to FIG. 12.

Before going into Figure 12, it should be noted that, according to Figure 11, the coil winding 8 is arranged on the stator poles 71 connected to the first holding plate 94. As can be seen from the top view of the holding plate 94 in FIG. 2 are arranged. The longitudinally extending sections 802, 803 are bent at the circumferential ends and form deflected sections 85 there. The coil winding 8 is formed by a continuous, with a Insulating layer provided winding wire is formed, which forms a plurality of coil turns of the coil winding 8.

According to Figure 12, two further rows of stator poles 71 are also firmly connected to the other holding plate 93 via an injection molding process and integrated into it. The holding plate 93 is the axially front holding plate in relation to the electrical machine of Figures 1-6. It is also referred to below as the second holding plate or upper holding plate.

The stator poles of rows 71-2 and 71-4 are connected to the second holding plate 93. This is done using an injection molding process in which the first holding plate 93 is formed in one step and at the same time one end of the stator poles 71 is connected to the holding plate 93. The corresponding injection molding process is carried out completely analogously to the production of the first holding plate 94 explained with reference to FIGS. 14 and 15, with simultaneous integration of the ends of the stator poles.

12, the second holding plate 93 forms two rows 95-1, 95-3 of recesses 95, which serve to hold the other ends 72 of the stator poles 71 of the two rows 71-1, 71-. 3, which are connected to the first holding plate 94 according to FIG. 10, these ends 72 being inserted into the second holding plate 93.

Figure 13 shows the finished assembly, with the two holding plates 94, 93 being arranged parallel to one another and the stator poles 71 of the respective holding plate extending in the direction of the other holding plate. The two partial winding spaces 80-1, 80-2 are formed by the total of four rows of stator poles, with two rows 71-1, 71-2 or 71-3, 71-4 of stator poles 71 being assigned to each other and between them form the respective partial winding space 80-1 or 80-2. The stator poles 71 of the rows 71-1 and 71-3 are concavely curved as explained when viewed from the radial outside. The stator poles 71 of the rows 72-2 and 71-4 are convexly curved when viewed from the radial outside.

The stator poles 71 of each row are thus firmly connected to one holding plate at one end 73, 72 and protrude at their other end 72, 73 into a recess 95 in the other holding plate. It should be noted that the coil winding 8 can be fixed in sections by fixation disks 86 in the partial winding spaces 80-1, 80-2, with the fixation disks 86 holding the individual coil turns 801 and each being supported on the stator poles 71 of one of the rows , which limit the winding space.

Figure 16 shows a flow chart of a first method for producing an assembly corresponding to Figures 7-15. First, in a first step 161, all stator poles of at least one row are connected at their first ends 73 to the first holding plate 94 as part of an injection molding process in which the first holding plate 94 is produced. This is done, for example, according to Figures 14 and 15. Furthermore, according to step 162, all stator poles of at least one assigned row are connected at their second ends 72 to the second holding plate 93, also as part of an injection molding process in which the second holding plate 93 is produced. This is also done, for example, in accordance with Figures 14 and 15.

The coil winding is arranged according to step 163 on the stator poles 71 connected to the first holding plate 94 or to the second holding plate 93. This is done, for example, via the fixation disks 86 mentioned, which are supported on the corresponding stator poles.

Subsequently, according to step 164, the two holding plates 94, 93 are arranged parallel to one another in such a way that the stator poles 71 of the respective holding plate extend in the direction of the other holding plate and thereby form at least one winding space between them, which contains the coil winding 8 or a section 802, 803 takes up the coil winding.

Furthermore, according to step 165, it is provided that the two ends 73, 72 of the stator poles 71 are each arranged in one of the holding plates, the stator poles 71 being firmly connected at one end to one of the holding plates and at their other end in corresponding recesses 95 in the other of the retaining plates are inserted. It can be provided in embodiments that the ends of the stator poles 61 inserted into a respective recess 95 are additionally fixed in the respective recess 95, for example with an adhesive.

17 shows a flowchart of a further method for producing an assembly according to FIGS. 7-15. According to step 171, all stator poles 71 are initially at least one row at their first ends 73 with the first Holding plate 94 connected. This connection can, but does not have to, be made using injection molding technology as shown in Figures 14 and 15. In principle, other connection techniques are also possible and it is also possible for the individual stator poles 71 to be connected individually and sequentially to the first holding plate 94.

Furthermore, in step 172, all stator poles of at least one assigned row are connected at their second ends 72 to the second holding plate 93. Here too, this connection can be made using injection molding technology, but does not have to be. In principle, other connection techniques are also possible here, including an individual and sequential connection of the individual stator poles 71 to the second holding plate 93.

The further steps 173-175 correspond to steps 163-165, so that reference is made to the corresponding statements on steps 163-165.

17, the focus is on the coil winding being arranged on the stator poles connected to one of the holding plates before the winding spaces or partial winding spaces are formed by two rows of stator poles assigned to each other, which are on the axially spaced holding plates are arranged. In the method according to FIG. 16, the focus is on the method of connecting the stator poles of a row to the respective holding plate in one step using injection molding technology.

It is to be understood that the invention is not limited to the embodiments described above and various modifications and improvements may be made without departing from the concepts described herein. It should also be noted that any of the features described can be used separately or in combination with any other features, provided they are not mutually exclusive. The disclosure extends to and includes all combinations and subcombinations of one or more features described herein. If ranges are defined, they include all values within these ranges as well as all sub-ranges that fall within a range.

Claims

Patent claims

1 . Assembly for an electrical machine, comprising: a coil winding (8) with a plurality of coil turns (801),

Stator poles (7) of a stator, which are arranged in at least two rows (71-1, 71-2; 71-3, 71-4) assigned to one another and spaced apart from one another, with two rows (71-1, 71-4) assigned to each other. 2; 71-3, 71-4) define between them a winding space (80, 80-1, 80-2) for receiving the coil winding (8) or a section (802, 803) of the coil winding (8), and each Stator pole (7) has a first end (73) and a second end (72), axially spaced, non-magnetic and non-magnetizable first and second holding plates (94, 93), the stator poles (71) being between the holding plates (94, 93) extend,

- All stator poles (71) of at least one of the rows (71-1, 71-3) are encapsulated at their first ends (73) with an injection molding material which forms the first holding plate (94).

2. Assembly according to claim 1, characterized in that all stator poles (71) of at least one row (71-2, 71-4) assigned to the row are encapsulated at their second ends (72) with an injection molding material which covers the second holding plate (93 ) forms.

3. Assembly according to claim 1 or 2, characterized in that the stator poles (71) of two mutually assigned rows (71-1, 71-2; 71-3, 71-4) are arranged offset from one another.

4. Assembly according to one of the preceding claims, characterized in that the stator poles (71) are each curved, the two rows (71-1, 71-2; 71-3, 71-4) of stator poles (71 ) are radially spaced, the radial direction relating to the axis of rotation of an electrical machine in which the assembly can be arranged, the stator poles (71) of the radially inner row (71-1, 71-3) are concavely curved when viewed from the radially outside and the stator poles (71) of the radially outer row (71-2, 71-4) are convexly curved when viewed from the radially outside, so that their mutually facing sections together define the winding space (80, 80-1, 80-2), where they limit the winding space (80, 80-1, 80-2) transversely to a circumferential direction along which the stator winding extends.

5. Assembly according to one of the preceding claims, characterized in that the stator poles (71) have a straight middle section (715) and two sections (716, 717) angled therefrom, each of which has one end (72, 73) of the stator poles (71). form.

6. Assembly according to one of the preceding claims, characterized in that the stator poles (71) of all rows (71-1, 71-2; 71-3, 71-4) are designed in an identical manner and the stator poles (71) of those assigned to one another Rows (71-1, 71-2; 71-3, 71-4) are arranged in reverse orientation.

7. Assembly according to one of the preceding claims, characterized in that the stator poles (71) are arranged in at least four rows (71-1, 71-2, 71-3, 71-4), with two of the rows (71- 1, 71-2; 71-3, 71-4) are assigned to each other and form a partial winding space (80-1, 80-2), the partial winding spaces (80-1, 80-2) being radially spaced apart Circumferential direction, and wherein sections (802, 803) of the coil winding (8) extending in the circumferential direction are arranged in the partial winding spaces (80-1, 80-2).

8. Assembly according to one of the preceding claims, characterized in that both ends (73, 72) of the stator poles (71) are each arranged in one of the holding plates (94, 93), the stator poles (71) being at one end (73 ) are firmly connected to one of the holding plates (83) and are inserted at their other end (72) into corresponding recesses (95) in the other of the holding plates (93).

9. Electric machine, which has: a rotor (11) provided with permanent magnets (5), which has an axis of rotation (110) which defines an axial direction, a radial direction and a circumferential direction, a stator (12), which is active Components stator poles (71) and a coil winding (8), the stator (12) being designed as a ring structure with a plurality of ribs (120) which adjoin one another in the circumferential direction, the active components (71, 8) of the stator (12 ) are formed by assemblies according to claim 1, and the assemblies are held and positioned by the ribs (120) of the ring structure. Electrical machine according to claim 9, characterized in that the rotor (11) comprises axially spaced outer walls (111, 112, 114), each of which has or integrates permanent magnets (5), the assemblies each being in a volume (122) between the axially spaced outer walls (111, 112, 114) of the rotor (11) protrude radially. Method for producing an assembly for an electrical machine, the assembly comprising: a coil winding (8) with a plurality of coil turns (801),

Stator poles (7) of a stator, which are arranged in at least two rows (71-1, 71-2; 71-3, 71-4) assigned to one another and spaced apart from one another, with two rows (71-1, 71-4) assigned to each other. 2; 71-3, 71-4) define between them a winding space (80, 80-1, 80-2) for receiving the coil winding (8) or a section (802, 803) of the coil winding (8), and each Stator pole (7) has a first end (73) and a second end (72), axially spaced, non-magnetic and non-magnetizable first and second holding plates (94, 93), the stator poles (71) being between the holding plates (94, 93), the method comprising the steps:

- Connecting (161) all stator poles of at least one row (71-1, 71-3) at their first ends (73) to the first holding plate (94) as part of an injection molding process in which the first holding plate (94) is produced. Method according to claim 11, characterized by the further step of connecting (162) all stator poles (71) of at least one associated row (71-2, 71-4) at their second ends (72) with the second holding plate (93) in the context of a Injection molding process in which the second holding plate (93) is produced. Method according to claim 11 or 12, characterized in that the coil winding (8) is arranged on the stator poles (71) connected to the first holding plate (94) or to the second holding plate (93) before the winding space (80, 80- 1, 80-2) is formed to accommodate the coil winding (8). Method according to one of claims 11 to 13, characterized in that the stator poles (71) are arranged in four rows (71-1, 71-2, 71-3, 71-4), with two of the rows (71-1 , 71-2; 71-3, 71-4) are assigned to each other and form a partial winding space (80-1, 80-2), the partial winding spaces (80-1, 80-2) being spaced radially in the circumferential direction run, with the partial winding spaces (80- 1, 80-2) sections (802, 803) of the coil winding (8) each extending in the circumferential direction are arranged, and the method comprises:

- Connecting all stator poles (71) of two of the rows (71-1, 71-3) at their first ends (73) to the first holding plate (94) as part of an injection molding process,

- Connecting all stator poles (71) of the other two rows (71-2, 71-4) at their second ends (72) to the second holding plate (93) as part of an injection molding process,

- Arranging two sections (802, 803) of the coil winding (8) on the two rows of stator poles (71) connected to the first holding plate (94) or to the second holding plate (93),

- Arrangement of the two holding plates (94, 93) parallel to one another in such a way that the stator poles (71) of the respective holding plate (94, 93) extend in the direction of the other holding plate (93, 94) and there are two partial winding spaces ( 80-1, 80-2), each of which accommodates one of the two sections (802, 803) of the coil winding (8). Method according to one of claims 11 to 14, characterized in that both ends (73, 72) of the stator poles (71) are each arranged in one of the holding plates (94, 93), the stator poles (71) being at one end (73 ) are firmly connected to one of the holding plates (94) and inserted at the other end (72) into corresponding recesses (95) in the other of the holding plates (93). Method for producing an assembly for an electrical machine, the assembly comprising: a coil winding (8) with a plurality of coil turns (801),

Stator poles (7) of a stator, which are arranged in at least two rows (71-1, 71-2; 71-3, 71-4) assigned to one another and spaced apart from one another, with two rows (71-1, 71-4) assigned to each other. 2; 71-3, 71-4) define between them a winding space (80, 80-1, 80-2) for receiving the coil winding (8) or a section (802, 803) of the coil winding (8), and each Stator pole (7) has a first end (73) and a second end (72), axially spaced, non-magnetic and non-magnetizable first and second holding plates (94, 93), the stator poles (71) being between the holding plates (94, 93), the method comprising the steps: - Connecting (171) all stator poles (71) of at least one row (71-1, 71-3) at their first ends (73) to the first holding plate (94),

- Connecting (172) all stator poles (71) of at least one assigned row (71-2, 71-4) at their second ends (72) to the second holding plate (93),

- Arranging (173) the coil winding (8) on the stator poles (71) connected to the first holding plate (94) or to the second holding plate (93),

- Arrangement (174) of the two holding plates (94, 93) parallel to one another in such a way that the stator poles (71) of the respective holding plate (94, 93) extend in the direction of the other holding plate (93, 94) and two are assigned to each other Rows (71-1, 71-2; 71-3, 71-4) form a winding space (80, 80-1, 80-2) between them for the coil winding (8).

17. The method according to claim 16, characterized in that all stator poles (71) of a row (71-1, 71-2; 71-3, 71-4) are simultaneously connected to the associated holding plate (94, 93).

18. The method according to claim 16 or 17, characterized in that the stator poles (71) of the at least one row (71-1, 71-3) are connected at their first end (73) to the first holding plate (94) as part of an injection molding process, in which the first holding plate (94) is produced, are connected and / or that the stator poles (71) of the at least one assigned row (71-2, 71-4) are connected at their second end (72) to the second holding plate (93) are connected as part of an injection molding process in which the second holding plate (93) is produced.

19. The method according to any one of claims 16 to 18, characterized in that the stator poles (71) are arranged in four rows (71-1, 71-2, 71-3, 71-4), with two of the rows (71 -1, 71-2; 71-3, 71-4) are assigned to one another and form a partial winding space (80-1, 80-2), the partial winding spaces (80-1, 80-2) being spaced apart radially extend in the circumferential direction, and wherein sections (802, 803) of the coil winding (8) extending in the circumferential direction are arranged in the partial winding spaces (80-1, 80-2), and wherein the method comprises:

- Connecting all stator poles (71) of two of the rows (71-1, 71-3) at their first ends (73) to the first holding plate (94),

- Connecting all stator poles (71) of the other two rows (71-2, 71-4) at their second ends (72) to the second holding plate (93),

- Arranging two sections (802, 803) of the coil winding (8) on the two rows (71-1, 72-2, 71-3, 71-) connected to the first holding plate (94) or to the second holding plate (93). 4) of stator poles (71), - Arrangement of the two holding plates (94, 93) parallel to one another in such a way that the stator poles (71) of the respective holding plate (94, 93) extend in the direction of the other holding plate (93, 94) and have two partial winding spaces ( 80-1, 80-2), each of which accommodates one of the two sections (802, 803) of the coil winding (8). Method according to one of claims 16 to 19, characterized in that both ends (73, 72) of the stator poles (71) are each arranged in one of the holding plates (94, 93), the stator poles (71) being at one end (73 ) are firmly connected to one of the holding plates (94) and inserted at the other end (72) into corresponding recesses (95) in the other of the holding plates (93).