CN112823464A

CN112823464A - Rotor for an electric motor, method for producing a rotor, and electric motor

Info

Publication number: CN112823464A
Application number: CN201980047922.9A
Authority: CN
Inventors: 丹尼尔·保罗; 马克·穆勒; 于尔根·穆塞尔; 马丁·莱曼; 马丁·斯托克
Original assignee: ThyssenKrupp AG
Current assignee: ThyssenKrupp AG
Priority date: 2018-07-17
Filing date: 2019-07-17
Publication date: 2021-05-18
Also published as: WO2020016320A2; WO2020016320A3; DE102018211865A1

Abstract

The invention relates to a rotor (R) for an electric motor, comprising a rotor shaft (1) and a rotor assembly (2) connected to the rotor shaft in a rotationally fixed manner, wherein the rotor assembly comprises at least one rotor disk (2a, 2b, …), wherein the rotor disk comprises at least two rotor disk segments (2 ', 2' …) arranged one behind the other in the circumferential direction, which are connected to one another by means of a connecting means (21), wherein the rotationally fixed connection between the rotor shaft (1) and the rotor assembly (2) comprises at least one first pressure plate (3) and one second pressure plate (4), wherein the at least one pressure plate is connected to the rotor shaft (1) in a rotationally fixed manner, wherein the rotor assembly (2) is clamped between the pressure plates (3, 4). The invention also relates to a method for producing a rotor and to an electric motor.

Description

Rotor for an electric motor, method for producing a rotor, and electric motor

Technical Field

The present invention relates to a rotor for an electric motor according to the preamble of claim 1, a method for manufacturing a rotor according to claim 20 and an electric motor according to the preamble of claim 23.

Background

A rotor for an electric machine is known, which comprises a rotor shaft and a rotor set connected to the rotor shaft at least in a rotationally fixed manner. The rotor set usually consists of several rotor disks, which are mounted in succession on a rotor shaft in the axial direction.

In this context, rotor disks are also known which are composed of individual rotor disk segments which are connected to one another by connecting means. This is a so-called segmented rotor disk. In this design, it is basically provided that the rotor disk is not integrally formed from sheet metal, but rather is formed from a plurality of rotor disk segments, which are combined to form the rotor disk. The use of a segmented rotor disk has the advantage that the material utilization is increased compared to, for example, a circular stamped rotor disk. Segmented stator elements or rotor elements are known, for example, from EP 2356734a 1.

On the other hand, such a segmented design of the rotor disk causes problems in the rotationally fixed connection of the rotor stack to the rotor shaft. Conventional, that is to say non-segmented, rotor stacks are usually connected to the rotor shaft in a transverse press connection (Querpressverband), for example by means of a shrink fit. With this transverse compression connection, tensile stresses occur in the circumferential direction. If this method is applied to a segmented rotor disk, the tensile stress can spread the connection means (verindringsmittel) of the rotor disk segments, i.e. the joint, and thus a secure fit against a force fit of the rotor set on the shaft.

Disclosure of Invention

The object of the present invention is accordingly to provide an improved rotor, preferably a rotor in which the problems outlined above do not occur or at least are reduced, in particular a rotor in which a reliable connection between a rotor set with segmented rotor disks and a rotor shaft can be ensured.

According to the invention, this object is achieved by a rotor having the features of claim 1.

Since the rotationally fixed connection between the rotor shaft and the rotor assembly comprises at least one first pressure plate and a second pressure plate, wherein the at least one pressure plate is connected at least rotationally fixed to the rotor shaft, wherein the rotor assembly is clamped between the pressure plates, a connection suitable for transmitting torque can be provided between the rotor assemblies having segmented rotor disks, wherein tensile stresses at the joints between the rotor disk segments are not to be expected, or at least not to be expected to a degree detrimental to the connection. In comparison to, for example, a hot transverse press connection, the joining also advantageously does not have a thermal influence on the sheet metal package.

Further advantageous embodiments of the invention are provided, in particular, by the features of the dependent claims. The bodies or features of different claims can in principle be combined with one another as desired.

In an advantageous embodiment of the invention, it can be provided, for example, that the rotor assembly comprises several rotor disks, which are arranged one behind the other in the axial direction of the rotor shaft. In this regard, the rotor set can be made up of several individual rotor disks. The rotor disks can be connected to one another by means of suitable connecting means.

In a further advantageous embodiment of the invention, it can be provided, for example, that the rotor shaft passes through an opening provided in the rotor group, wherein a circumferential gap is provided between the rotor shaft and the opening. In other words, it is preferably provided that the plate package inner geometry is spaced apart from the rotor shaft outer diameter by a gap, and that the centering of the plate package relative to the rotor shaft is effected via the outer diameter of the plate package. This is particularly advantageous because the cost of the components is reduced by shortening the component tolerance chain, since the precision can in turn be achieved by the assembly process with the outer centering device. Furthermore, it is preferably not necessary to machine the rotor shaft underneath the sheet metal pack. Preferably, no radial forces and no transverse compressive connections occur in the sheet metal pack. Preferably, heat can be dissipated through the gap.

For mounting the pressure plate on the rotor shaft, various advantageous variants are conceivable.

In an advantageous embodiment of the invention, it can be provided, for example, that the pressure plate is mounted directly on the rotor shaft or is formed integrally with the rotor shaft. This variant saves material and is simple to implement in terms of production technology.

In a further advantageous embodiment of the invention, it can be provided, for example, that the pressure plate is mounted on the flange or is designed in one piece with the flange, wherein the flange is connected to the rotor shaft. In this variant, for example, the different rotor shaft ends may be provided by flanges. Furthermore, the production of the rotor shaft is generally simpler to design, since the flange comprising the respective pressure plate can be produced separately.

In a further advantageous embodiment of the invention, it can be provided, for example, that the rotor group, in particular the rotor disks, preferably at least one rotor disk section, is equipped with at least one magnet, in particular a permanent magnet. Depending on the type of electric machine, other electromagnetic components/electrically conductive conductors, such as short-circuit bars or windings, can also be arranged in the rotor disk instead of magnets.

In a further advantageous embodiment of the invention, it can be provided, for example, that the rotor stack, in particular the rotor disks, preferably at least one rotor disk section, is equipped with at least one pocket for accommodating a magnet. The pocket is accordingly used to reliably receive the magnet.

In a further advantageous embodiment of the invention, it can be provided, for example, that the pocket is completely surrounded by the material of the rotor disk section.

In a further advantageous embodiment of the invention, it can be provided, for example, that the pockets are open toward the rotor disk segment edges, wherein the pockets are preferably closed by the rotor disk segment edges of adjacent rotor disk segments.

In a further advantageous embodiment of the invention, it can be provided, for example, that the pocket is open in the radial direction.

In a further advantageous embodiment of the invention, it can be provided that the rotor disk segments are connected to one another by connecting means, in particular form-fitting connecting means, preferably dovetail-shaped connecting means. By this measure, the rotor disk segments can be connected to one another in a simple manner to form a circular rotor disk.

In a further advantageous embodiment of the invention, it can be provided that at least two rotor disks are arranged offset to one another. This results in a higher stability of the rotor set, similar to the offset during masonry.

In a further advantageous embodiment of the invention, it can be provided that at least one tie rod is arranged between two rotor segments arranged next to one another in the circumferential direction. The tie rods between the rotor segments are preferably used to receive tensile forces in the circumferential direction at the same time as compressive forces in the radial direction, which act on the tie rods, in particular under the effect of centrifugal forces, radially outward via the windings and the casting compound.

In a further advantageous embodiment of the invention, it can be provided that the rotor segments are designed in the form of a T, which comprises one long arm and two rotor teeth, wherein the tie rod is arranged between the rotor segments, in particular the rotor teeth, which are arranged next to one another in the circumferential direction.

In a further advantageous embodiment of the invention, it can be provided that the tie rod is equipped with a positive-fit and/or non-positive-fit connection means between the tie rod and the rotor section.

In a further advantageous embodiment of the invention, it can be provided that the connecting means is designed as a T-shaped or L-shaped profile. This construction can be easily manufactured on the end side of the tie rod. The T-shaped profile can be easily pushed axially into a corresponding recess in the rotor section, for example. The L-shaped profile can for example be easily snapped on, but can also be inserted.

In a further advantageous embodiment of the invention, it can be provided that one or more rotor segments are equipped with a cast form-fitting groove, wherein the cast form-fitting groove is preferably provided in the long arm of the rotor segment. Such cast form-fitting grooves have, for example, a dovetail shape. By casting with a casting compound, further stabilization of the rotor segment composite or the rotor disk composite can be achieved.

In a further advantageous embodiment of the invention, it can be provided that at least one pressure plate, preferably both pressure plates, are equipped with receiving means for the winding heads. The winding head may be enclosed. It is possible to absorb centrifugal forces acting on the winding and/or to prevent plastic deformation.

In a further advantageous embodiment of the invention, it can be provided that the receiving means is designed as a recess, in particular as a recess corresponding to the winding head. This makes it possible, for example, to produce a form-fitting connection, which in turn serves to increase the stability of the rotor.

In a further advantageous embodiment of the invention, it can be provided that the casting compound is arranged in the intermediate space between the recess and the winding head. By this measure, a part of the torque transmission can be achieved by the pressure disk.

Another object of the invention is to provide an advantageous method for producing a rotor according to the invention.

According to the invention, this object is solved by a method having the method steps according to claim 20. Furthermore, due to the remaining clearance between the rotor set and the rotor shaft, a centering device may be used, which is in contact with the outer diameter or outer surface of the rotor set. This centering device may also be referred to as an outer centering device.

Another object of the present invention is to provide an improved electric motor, in particular an electric motor, in which a reliable connection between a rotor set having segmented rotor disks and a rotor shaft can be ensured.

According to the invention, this object is solved by an electric motor having the features of the characterizing portion of claim 23.

Drawings

Further features and advantages of the invention will become apparent from the following description of preferred embodiments with reference to the accompanying drawings. Wherein

Fig. 1 shows a rotor according to the invention in a side view;

fig. 2 shows a rotor according to the invention in a sectional side view;

fig. 2a shows a rotor according to the invention in a sectional view in front;

FIG. 3a shows an offset arrangement of the rotor disks in a first condition;

FIG. 3b shows the arrangement of the offset of the rotor disks in the second condition;

FIG. 4 shows a connection device (variant) between rotor disk segments;

FIG. 5 illustrates one embodiment of a platen;

FIG. 6 illustrates one embodiment of a platen;

FIG. 7 illustrates one embodiment of a platen;

FIG. 8 illustrates one embodiment of a platen;

FIG. 9 illustrates one embodiment of a platen;

fig. 10 shows a magnet and pocket arrangement possibility (variation);

figure 11 shows a rotor with a centring device;

figure 12 shows an electric motor according to the invention;

fig. 13 shows a detail of the rotor according to the invention, in particular of the tie rods between the rotor segments;

FIG. 14 shows a detail of FIG. 13;

FIG. 15 shows a T-shaped end of the tie rod;

FIG. 16 shows an L-shaped end of the tie rod;

fig. 17 shows a schematic cross-sectional view through a rotor according to the invention.

List of reference numerals

L axis of rotation/longitudinal axis

R rotor

S stator

F_ZTension force

F_DPressure of

1 rotor shaft

2 rotor set

2a, 2b, … rotor disks

2', 2 ", … rotor disk segment

3 first platen

4 second platen

5 bags

6 magnet

7 gap

8 openings/holes

9 centering device

10 Flange

21 (of rotor disk segments) connection device

22 (of rotor disks)

23 short-circuit bar

24 long arm

25 rotor tooth

26 (for rotor disk segments) tie rods

27 casting form-fitting groove

28 winding head

29 receiving device/recess

30 draw-bar (axial, for rotor disc)

31 connecting device

32 casting material

Detailed Description

The rotor R for an electric motor according to the invention basically comprises a rotor shaft 1 and a rotor set 2. The rotor assembly 2 is basically rotationally symmetrical and accordingly has a rotational axis L or a longitudinal axis in the axial direction. The rotor set 2 is provided with openings 8 or holes along this longitudinal axis. The rotor assembly 2 thus overall has a hollow cylindrical shape.

The rotor shaft 1 is inserted through the opening 8 and is connected at least in a rotationally fixed, preferably fixed manner to the rotor assembly 2. The rotor shaft 1 is preferably a hollow shaft.

The rotor group 2 comprises

several rotor disks

2a, 2b, … of substantially circular design, preferably made of steel sheet. The thickness of the rotor disk can be selected based on centrifugal force. The

rotor disks

2a, 2b … are arranged along the rotor shaft 1 in the axial direction and form a rotor group 2. The rotor disks 2 can be connected to one another via suitable means. Preferably, the

rotor disks

2a, 2b, … are connected to one another by one or more connecting means 22 acting in the circumferential direction, for example punched projections, adhesive joints or the like. Accordingly, the connection means 22 contribute to the rotor discs not being able to rotate relative to each other. Furthermore, the adhesive connection means also serve for axial fixing.

Furthermore, the rotor or rotor set 2 can be equipped with a short-circuit bar 23. Preferably, the shorting bars extend parallel to the rotation axis L in the axial direction. Preferably, the plurality of shorting bars are arranged side by side in the circumferential direction. The shorting bars are preferably solid copper bars, which are preferably connected to the pressure plate (fig. 8) or together with the other shorting bar ends form a shorting ring in the circumferential direction (fig. 9).

Such a rotor disk comprises at least two, preferably several, rotor disk segments 2', 2 ″ …, which are arranged one behind the other in the circumferential direction and are preferably connected to one another via a connecting piece 21. The connecting means 21 are preferably form-fitting connecting means, in particular a tongue-and-groove connection, for example according to the type of a dovetail connection (Schwalbenschwanzverbindung). The option of a form-fitting connection is given, for example, in DE 202004005652U 1. Other connecting means, such as adhesive connecting means, in particular adhesives, are also conceivable. Numerous variations in the number, shape and location of the segments are contemplated.

Different situations are also conceivable for the arrangement of the rotor disk segments in the circumferential direction. In particular, the rotor disks or the groups of rotor disks can be arranged offset from one another. In particular, a deflection of the butt edge (Sto β kante) between the rotor disk sections is provided, similar to the deflection during the laying process. In this case, the abutment edges are not arranged one behind the other in the axial direction, but are arranged offset from one another in each layer or in a plurality of layers. Fig. 3 shows two exemplary embodiments in which the respective rotor disk segments 2' of the rotor disks 2a to 2d are directly axially offset in succession (fig. 3 a). Alternatively, fig. 3b shows that the groups of a plurality of

rotor disks

2a, 2b, 2c on the one hand and 2d, 2e, 2f on the other hand are arranged offset.

The rotor assembly 2 is at least rotationally fixed, i.e. connected to the rotor shaft 1 via a connection suitable for transmitting torque.

According to the invention, it is proposed that the rotationally fixed connection between the rotor shaft 1 and the rotor group 2 is realized by means of an axially acting press connection, which may also be referred to as a press fit. The rotationally fixed connection essentially comprises a first pressure plate 3 and a second pressure plate 4, wherein at least one pressure plate, but preferably both

pressure plates

3, 4, is connected rotationally fixed to the rotor shaft 1, wherein the rotor set 2 is clamped between the

pressure plates

3, 4. The introduction of torque can accordingly be effected via one or two pressure disks depending on the shaft stiffness.

The

pressure plates

3, 4 exert a pressure force on the rotor set 2 in the axial direction, so that there is at least a friction-fit and/or form-fit connection between the

pressure plates

3, 4 and the rotor set 2 and finally a connection for transmitting a torque between the rotor shaft 1 and the rotor set 2 is produced. Preferably, the torque transmission is from the rotor disk section to the pressure plate. There may also be a friction fit between the rotor disks.

The

pressure plate

3 or 4 is preferably designed as a circumferentially continuous pressure plate. In other words, the pressure plate projects radially like a circumferential flange from the rotor shaft 1. In addition, the

pressure plates

3, 4 axially fix the rotor set 2. It is thereby preferably provided that the

pressure plates

3, 4 are also connected to the rotor shaft 1 in an axially fixed manner, i.e. in an axially immovable manner. This also applies indirectly, for example, when using the flange 10 described in more detail below.

Different variants are conceivable for one or

more platens

3, 4.

In the first embodiment, it can be provided that the pressure plate 3 and/or 4 is embodied as a separate component with respect to the rotor shaft 1. The pressure plate 3 and/or 4 is pushed onto the rotor shaft 1 and is connected to it in a rotationally fixed manner by suitable means. The rotor shaft 1 typically forms one or more axial ends of the rotor.

In another embodiment, the pressure plate 3 and/or 4 is formed on the flange 10 or is integrally formed with the flange 10. The flange 10 can be inserted into the rotor shaft 1 in sections. A portion of the flange 10 projects axially from the rotor shaft 1 and forms an axial end of the rotor. As is usual, the pressure plate 3 and/or 4 projects radially beyond the flange 10 or the rotor shaft 1.

The above-described embodiments can also be applied jointly to the rotor, i.e. the first variant is at one end of the rotor and the other variant is at the other end of the rotor.

It is also conceivable that the pressure plate is already integrally formed with the rotor shaft. Accordingly, the second platen may be configured as described above.

Furthermore, it is preferably provided that a circumferential gap 7 is formed between the rotor shaft 1 and the bore 8 of the rotor stack 2, in particular in the axial direction along the rotor shaft. This gap may also be referred to as a free space between the outer surface of the rotor shaft 1 and the inner surface of the bore 8. In particular, no transverse press connection is provided between the rotor shaft 1 and the rotor assembly 2.

The centering of the rotor set 2 is preferably performed via the outer surface of the rotor set 2. For this purpose, a centering device 9 is provided, which interacts with the outer surface of the rotor set 2. Such a centering device is described, for example, in DE 102015216971 a 1.

The rotor group 2, in particular the

rotor disks

2a, 2b, …, preferably at least one rotor disk segment 2', 2 ″ …, is equipped with at least one magnet 6, in particular a permanent magnet. In this case, pockets 5 can be provided in the rotor disk group 2, in particular in the

rotor disks

2a, 2b, …, preferably in the rotor disk segments 2', 2 ″ …, wherein different designs can be considered. Thus, the pockets 5 can be completely surrounded by the material of the rotor disk section, for example. The pockets 5 may be open towards the rotor disc segment rim. The pockets 5 are in this case preferably closed by adjacent rotor disk segments. In a further alternative or additional embodiment, the pocket may also be radially open.

For the magnets and ultimately also for the pockets, different spatial designs can be considered, preferably rectangular or circular segments. Preferably, a plurality of pockets and magnets are provided in the rotor set or rotor disk segment.

The mounting of the rotor R according to the invention preferably comprises at least the following method steps:

a) fixing the first pressure plate 3 on the rotor shaft 1 or the flange 10, or inserting the flange 10 with the first pressure plate 3 into the rotor shaft 1

b) Insert rotor set 2

c) Centering of the rotor set 2 by means of a centering device 9 acting on the outer diameter of the rotor set

d) Threading device

Second platen 4

e) Compressing the rotor set 2 by pushing the

pressure plates

3, 4 together

f) The second platen 4 is fixed.

Before the insertion of the rotor set 2, further preferred method steps are carried out:

circular arrangement of rotor disk segments (2 ', 2' …)

Connection of rotor disk segments (2 ', 2' …)

-arranging the rotor discs (2a, 2b, 2c, …) axially into a rotor group.

It is further preferably provided that the rotor disks are arranged in an offset manner.

The electric motor according to the invention basically comprises a rotor and a stator. The rotor is preferably the above-mentioned rotor.

The present invention is not limited to any particular motor type. The types of motors may be, for example: permanent magnet synchronous machines (PSM), asynchronous machines (ASM), direct current series motors (GRM), external excitation synchronous machines (FSM).

Further advantageous embodiments of the rotor according to the invention are shown in fig. 13 to 17.

Reference is made to the embodiments made above with respect to the basic structure of the rotor.

Fig. 13 shows a section of a rotor disk 2a, which rotor disk 2a comprises at least two rotor sections 2', 2 ″. These rotor segments have an at least partially T-shaped form and accordingly have one long radially extending arm 24 and two rotor teeth 25 extending in the circumferential direction.

Tie rods 26 are provided between the rotor teeth of two rotor segments arranged next to one another, in particular of two rotor segments 2', 2 ″. For the connection between the rotor segment 2' or 2 ″ and the tie rod 26, the end region of the tie rod is equipped with a connecting means 31. The connecting means 31 can be designed, for example, as a T-shaped or L-shaped profile which engages in a corresponding recess (aussaprung) of the rotor section and can establish at least one form-fitting and/or force-fitting connection between the tie rod 26 and the rotor section. The T-shaped profile can be pushed axially into a corresponding recess of the rotor section. The L-shaped profile can be pushed axially or snapped radially into a corresponding recess of the rotor section.

Also shown by arrows in fig. 14, the tie rod is adapted to transmit a pulling force F_ZAnd/or pressure F_D。

Furthermore, it is provided that one or more rotor segments 2 ', 2 ", 2'" are equipped with a cast form-fitting groove (Vergussformschlussnut) 27. Preferably, a cast form-fitting groove 27 is provided in the long arm 24 of the rotor section.

Preferably, provision is made here for at least one of the platens 3 and/or 4, preferably both platens, to be equipped with receiving means 29 for the winding heads 28. The winding heads 28 are usually formed by windings or connection tabs for short-circuit bars, projecting axially from the rotor set 2. The receiving means 29 for the winding heads are usually designed as corresponding recesses which are correspondingly provided for receiving the winding heads 28, in particular for positively receiving the winding heads 28. Furthermore, it can be provided that the casting compound 32 fills the intermediate space between the recess 29 and the winding head 28 and hardens there.

Furthermore, it can be provided that the rotor or the rotor assembly is equipped with at least one, preferably more, axially extending tie rods 30. The

rotor disks

2a, 2b, … are additionally pressed against one another and fixed by means of tie rods 30.

A device and a method of the above-mentioned type are used, for example, in the production of electric motors for motor vehicles.

The features and details described in connection with the method are of course also applicable to the features and details described in connection with the device according to the invention and vice versa, so that the disclosure with respect to the various inventive aspects is always or may be referred to one another. Furthermore, the method according to the invention can be carried out with the device according to the invention.

Claims

1. Rotor (R) for an electric motor, comprising a rotor shaft (1) and a rotor set (2) connected at least in a rotationally fixed manner thereto, wherein the rotor set comprises at least one rotor disk (2a, 2b, …), wherein the rotor disk comprises at least two rotor disk segments (2 ', 2' …) arranged one behind the other in the circumferential direction,

it is characterized in that the preparation method is characterized in that,

the rotationally fixed connection between the rotor shaft (1) and the rotor assembly (2) comprises at least one first pressure plate (3) and a second pressure plate (4), wherein the at least one pressure plate is connected to the rotor shaft (1) at least rotationally fixed, wherein the rotor assembly (2) is clamped between the pressure plates (3, 4).

2. The rotor according to claim 1, characterized in that the rotor group (2) comprises a plurality of rotor disks (2a, 2b, …) arranged one after the other in the axial direction of the rotor shaft (1).

3. Rotor according to at least one of the preceding claims, characterized in that the rotor shaft (1) passes through an opening (8) provided in the rotor group (2), wherein a surrounding gap (7) is provided between the rotor shaft and the opening.

4. Rotor according to at least one of the preceding claims, characterized in that the pressure plate (3 and/or 4) is mounted directly on the rotor shaft (1) or is designed in one piece therewith, or the pressure plate (3 and/or 4) is mounted on a flange (10) or is designed in one piece therewith, wherein the flange is connected with the rotor shaft (1).

5. Rotor according to at least one of the preceding claims, characterized in that the rotor group (2), in particular the rotor disks (2a, 2b, …), preferably at least one rotor disk section (2', 2 ", …), is equipped with at least one magnet (6), in particular a permanent magnet.

6. Rotor according to at least one of the preceding claims, characterized in that the rotor group (2), in particular the rotor disks (2a, 2b, …), preferably at least one rotor disk section (2', 2 ", …), is equipped with at least one pocket (5) for accommodating the magnet (6).

7. The rotor according to at least one of the preceding claims, characterized in that the pockets (5) are completely surrounded by the material of the rotor disc segments (2', 2 "…).

8. The rotor according to at least one of the preceding claims, characterized in that the pockets (5) are open towards the rotor disk segment edge, wherein the pockets (5) are preferably closed by an adjacent rotor disk segment edge of a rotor disk segment.

9. The rotor according to at least one of the preceding claims, characterized in that the pockets (5) are open in a radial direction.

10. Rotor according to at least one of the preceding claims, characterized in that the rotor disk segments (2', 2 "…) are connected to one another by means of connecting means (21), in particular form-fitting connecting means, preferably dovetail-shaped connecting means.

11. Rotor according to at least one of the preceding claims, characterized in that at least two rotor discs are arranged offset to each other.

12. Rotor according to at least one of the preceding claims, characterized in that at least one tie rod (26) is provided between two rotor segments (2', 2 ") arranged side by side in the circumferential direction.

13. Rotor according to at least one of the preceding claims, characterized in that the rotor section is designed as a T-shape, comprising one long arm (24) and two rotor teeth (25), wherein the tie rods (26) are arranged between the rotor teeth (25) arranged side by side in the circumferential direction.

14. Rotor according to at least one of the preceding claims, characterized in that the tie rod (26) is equipped with a connecting means (31) for a form-fit and/or force-fit connection between the tie rod (26) and the rotor section (2' and/or 2 ").

15. The rotor according to at least one of the preceding claims, characterized in that the connecting means (31) are designed as a T-shaped or L-shaped profile.

16. Rotor according to at least one of the preceding claims, characterized in that one or more of the rotor segments (2 ', 2 ") is equipped with a cast form-fitting groove (27), wherein the cast form-fitting groove (27) is in particular provided in the rotor segment's long arm (24).

17. Rotor according to at least one of the preceding claims, characterized in that at least one pressure plate (3 and/or 4), preferably both pressure plates, is equipped with receiving means (29) for a winding head (28).

18. The rotor according to at least one of the preceding claims, characterized in that the receiving means (29) are designed as recesses, in particular as recesses corresponding to the winding heads (28).

19. Rotor according to at least one of the preceding claims, characterized in that a casting compound (32) is arranged in the intermediate space between the recess (29) and the winding head (28).

20. Method for manufacturing a rotor (R) according to at least one of the preceding claims, in particular according to claim 3, characterized in that it comprises at least the following method steps:

-fixing the first pressure plate (3) on the rotor shaft (1) or the flange (10), or inserting the flange (10) with the first pressure plate (3) into the rotor shaft (1)

-inserting the rotor set (2)

-centring of the rotor set (2) by means of centring means (9) acting on the outer diameter of the rotor set

-threading a second platen (4)

-compressing the rotor set (2) by pushing the pressure plates (3, 4) together

-fixing a second platen (4).

21. Method according to claim 20, characterized in that the following method steps are carried out before inserting the rotor set (2):

circular arrangement of rotor disk segments (2 ', 2' …)

Connection of rotor disk segments (2 ', 2' …)

-arranging the rotor discs (2a, 2b, 2c, …) axially into a rotor group.

22. Method according to at least one of the preceding claims, characterized in that the rotor disks are arranged in an offset manner.

23. Electric motor comprising a rotor (R) and a stator (S), characterized in that said rotor is a rotor (R) according to at least one of the preceding claims.