STATOR FOR AN ELECTRIC MACHINE AND METHOD FOR PRODUCING A STATOR FOR AN ELECTRIC MACHINE

Abstract

A stator for an electric machine comprises a stator core, at least two grooves which are arranged in the stator core, an electrical winding which comprises at least two dimensionally stable electrical conductors, and at least one interconnecting element on at least one side of the stator core, wherein at least one of the conductors is arranged in the grooves, respectively, the interconnecting element is electrically connected to at least one of the conductors, the interconnecting element is mechanically connected to the stator core via at least one of the conductors, the conductors are each mechanically fixed in the grooves, and the mechanical connection between the interconnecting element and the stator core is self-supporting via at least one of the conductors. In addition, an electric machine and a method for producing a stator for an electric machine are specified.

Claims

1. A stator for an electric machine, the stator comprising: a stator core, at least two grooves which are arranged in the stator core, an electrical winding which comprises at least two dimensionally stable electrical conductors, and at least one interconnecting element on at least one side of the stator core, wherein in each case at least one of the conductors is arranged in the grooves, the interconnecting element is electrically connected to at least one of the conductors, the interconnecting element is mechanically connected to the stator core via at least one of the conductors, the conductors are each mechanically fixed in the grooves, and the mechanical connection between the interconnecting element and the stator core is self-supporting via at least one of the conductors.

2. The stator according to claim 1, wherein the interconnecting element is mechanically connected in a form-fitting manner to at least one of the conductors.

3. The stator according to claim 1, wherein the interconnecting element has at least one recess.

4. The stator according to claim 3, wherein the interconnecting element is mechanically and electrically connected to one of the conductors in the region of the recess.

5. The stator according to claim 3, wherein one of the conductors extends through the recess.

6. The stator according to claim 3, wherein the recess has a shape for positioning a conductor in the recess.

7. The stator according to claim 1, which has an insulation system which is arranged at least in intermediate spaces between the stator core and the conductors and/or between the stator core and the interconnecting element.

8. The stator according to claim 1, which has at least one further interconnecting element.

9. The stator according to claim 8, wherein the interconnecting element and the further interconnecting element are electrically insulated from one another.

10. The stator according to claim 8, wherein the interconnecting element and the further interconnecting element have an intermeshing shape in places.

11. An electric machine having a stator according to claim 1 and a rotor which is movable relative to the stator.

12. A method for producing a stator for an electric machine comprising the following steps: providing a stator core of the stator with at least two grooves, introducing at least two dimensionally stable electrical conductors into the grooves, wherein at least one of the conductors is arranged in the grooves, respectively, mechanically fixing the conductors in the respective grooves, and attaching at least one interconnecting element to at least one side of the stator core, wherein an electrical winding of the stator comprises the conductors and the interconnecting element, the interconnecting element is electrically connected to at least one of the conductors, the interconnecting element is mechanically connected to the stator core via at least one of the conductors, the conductors are each mechanically fixed in the grooves, and the mechanical connection between the interconnecting element and the stator core is self-supporting via at least one of the conductors.

13. The method according to claim 12, wherein the stator has at least one further interconnecting element, and the interconnecting element and the further interconnecting element are mechanically connected to one another and electrically insulated from one another before being attached to the stator core.

14. The method according to claim 12, wherein the interconnecting element is electrically connected to at least one of the conductors by cold welding, laser welding, electron beam welding, metal inert gas welding, metal active gas welding, friction stir welding, soldering or via pressure or spring contacts.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0039] FIGS. 1, 2 and 3 show exemplary embodiments of the stator.

[0040] FIG. 4 shows an exemplary embodiment of the electric machine.

[0041] An exemplary embodiment of the method for producing a stator for an electric machine is described with FIG. 5.

[0042] A further exemplary embodiment of the stator is described with FIGS. 6 and 7.

[0043] Sectional illustrations through further exemplary embodiments of the stator are shown in FIGS. 8 and 9.

[0044] FIGS. 10 and 11 show excerpts from further exemplary embodiments of the stator.

DETAILED DESCRIPTION

[0045] An exemplary embodiment of a stator 20 for an electric machine 21 is shown in FIG. 1. The view in FIG. 1 is an oblique side view, in which not the entire stator 20 is illustrated. The stator 20 comprises a stator core 22, which has the shape of a cylinder. A plurality of grooves 23 is arranged in the stator core 22. The grooves 23 extend completely through the stator core 22. Moreover, the grooves 23 are arranged next to one another along a circumference of the stator core 22. The grooves 23 each have identical spacings with respect to one another. Therefore, the grooves 23 are distributed uniformly along the circumference of the stator core 22.

[0046] One dimensionally stable electrical conductor 25 is arranged in the grooves 23, respectively. The grooves 23 are open toward the center of the stator core 22. The conductors 25 do not completely fill the grooves 23 in each case. Adjoining the openings, the grooves 23 each have a region which is free of the conductors 25. The conductors 25 are a rod, respectively. Along a longitudinal axis of the stator core 22, the conductors 25 extend out of the stator core 22. Therefore, the conductors 25 project out of the stator core 22 on one side. The conductors 25 all project out of the stator core 22 by the same length.

[0047] The stator 20 further has a plurality of interconnecting elements 26. The stator 20 can have a plurality of interconnecting elements 26 and at least one further interconnecting element 29. The interconnecting elements 26 and the further interconnecting element 29 can have the same construction and the same features. The interconnecting elements 26 are arranged on at least one side of the stator core 22. In addition, the stator 20 has a plurality of electrical windings 24. Each electrical winding 24 of the stator 20 has at least two of the conductors 25 and at least one interconnecting element 26 or at least one further interconnecting element 29.

[0048] The interconnecting elements 26 each have the shape of a ring segment. The interconnecting elements 26 are arranged distributed along the circumference of the stator core 22. In addition, some of the interconnecting elements 26 are arranged one above the other along the longitudinal axis of the stator core 22. The interconnecting elements 26 have an electrically conductive material.

[0049] Each of the interconnecting elements 26 is electrically connected to at least one of the conductors 25. In this case, each of the interconnecting elements 26 is electrically connected to two conductors 25. This means that two of the conductors 25 are electrically connected to one another, respectively, via one interconnecting element 26, respectively. For this purpose, each interconnecting element 26 has two recesses 27. In the region of the recesses 27, each of the interconnecting elements 26 is mechanically and electrically connected to one of the conductors 25, respectively. For this purpose, one of the conductors 25 extends through each of the recesses 27. This means that one of the conductors 25 is arranged in each of the recesses 27. In the region of the recesses 27, the interconnecting elements 26 are mechanically connected in a form-fitting manner to one of the conductors 25, respectively. The interconnecting elements 26 and the conductors 25 can be electrically and mechanically connected to one another via different processes in the region of the recesses 27, respectively. For example, the connection between an interconnecting element 26 and a conductor 25 is achieved by cold welding, laser welding, electron beam welding, metal inert gas welding, metal active gas welding, friction stir welding, soldering or via pressure or spring contacts.

[0050] Each of the interconnecting elements 26 is mechanically connected to the stator core 22 via at least one of the conductors 25, respectively. In addition, the conductors 25 are mechanically fixed in the grooves 23, respectively. This makes it possible that the mechanical connection between the respective interconnecting element 26 and the stator core 22 is self-supporting via at least one of the conductors 25. This mechanical connection is therefore so stable that no further mechanical connection is required.

[0051] Furthermore, the interconnecting elements 26 are electrically insulated from one another. This means that each of the interconnecting elements 26 is electrically insulated from the other interconnecting elements 26. In addition, the interconnecting elements 26 are electrically insulated from the further interconnecting element 29. For this purpose, an electrically insulating material can be arranged between the interconnecting elements 26 and the further interconnecting element 29. The insulating material is not shown in FIG. 1. Furthermore, it is possible for the interconnecting elements 26 and/or the further interconnecting element 29 to be electrically insulating in places by a surface treatment.

[0052] A further exemplary embodiment of the stator 20 is shown in FIG. 2. The only difference from the construction shown in FIG. 1 is that the stator 20 additionally has a casing 31. The casing 31 surrounds the stator core 22 in lateral directions x, wherein the lateral directions x run perpendicularly to the longitudinal axis of the stator core 22. Moreover, the casing 31 surrounds the interconnecting elements 26 in lateral directions x. The casing 31 may have aluminum.

[0053] In FIG. 3, the exemplary embodiment of the stator 20 from FIG. 1 is shown in a tilted plan view.

[0054] An exemplary embodiment of the electric machine 21 is shown in FIG. 4. The electric machine 21 has a stator 20 as shown in FIG. 2. Moreover, the electric machine 21 has a rotor 30 which is movable relative to the stator 20. The rotor 30 is an internal rotor and is arranged in the stator 20.

[0055] An exemplary embodiment of the method for producing a stator 20 for an electric machine 21 is described with FIG. 5. In a first step S1, the stator core 22 of the stator 20 is provided. The stator core 22 has at least two grooves 23. In a second step S2, at least two dimensionally stable electrical conductors 25 are formed in the grooves 23, wherein at least one of the conductors 25 is arranged in the grooves 23, respectively. In addition, the conductors 25 are mechanically fixed in the grooves 23. In a third step S3, at least one interconnecting element 26 is attached to at least one side of the stator core 22. For this purpose, the interconnecting element 26 is electrically and mechanically connected to at least one of the conductors 25. This can be achieved by cold welding, laser welding, electron beam welding, metal inert gas welding, metal active gas welding, friction stir welding, soldering or via pressure or spring contacts.

[0056] In an optional step before the third step S3, at least one interconnecting element 26 and at least one further interconnecting element 29 are mechanically connected to one another and electrically insulated from one another before being attached to the stator core 22. The interconnecting element 26 and the further interconnecting element 29 can be mechanically connected to one another via an insulation resin, a composite material, adhesively bonded insulations, a casting compound or a plastic injection molding. The electrical insulation of the interconnecting elements 26 from one another can be achieved by virtue of the fact that an electrically insulating material is arranged between the interconnecting elements 26. Furthermore, it is possible for the interconnecting element 26 and/or the further interconnecting element 29 to have a surface treatment. In the region of the surface treatment, the interconnecting element 26 and/or the further interconnecting element 29 can be electrically insulating.

[0057] A further exemplary embodiment of the stator 20 is shown in FIG. 6. In comparison with the exemplary embodiment shown in FIG. 1, one of the interconnecting elements 26 is not illustrated in FIG. 6 for illustration. Moreover, the interconnecting elements 26 and the further interconnecting element 29 are electrically insulated from one another. For this purpose, an electrically insulating material 32 is arranged between the interconnecting elements 26 and the further interconnecting element 29. Furthermore, it is possible for the interconnecting elements 26 and/or the further interconnecting element 29 to have a surface treatment. In the region of the surface treatment, the interconnecting elements 26 and/or the further interconnecting element 29 are electrically insulating. In FIG. 6, it is shown that the electrically insulating material 32 is arranged on the interconnecting elements 26 which are exposed since one of the interconnecting elements 26 is not illustrated. Also in lateral directions x between the interconnecting elements 26, the electrically insulating material 32 is arranged. Below the location at which one of the interconnecting elements 26 is not illustrated, a section in the stator core 22 is illustrated. In this section, it can be seen that the electrically conductive material 32 is also situated between the interconnecting elements 26 and the stator core 22.

[0058] In FIG. 7, an excerpt from the exemplary embodiment of the stator 20 shown in FIG. 6 is illustrated. Also in FIG. 7, one of the interconnecting elements 26 is not illustrated for illustration. The electrically insulating material 32 is arranged on the upper side 33 of the interconnecting element 26 situated therebelow. The upper side 33 of the interconnecting elements 26 and of the further interconnecting elements 29 faces away from the stator core 22.

[0059] FIG. 8 shows a sectional illustration through part of a further exemplary embodiment of the stator 20. The stator 20 additionally has an insulation system 28. The insulation system 28 is arranged in intermediate spaces between the stator core 22 and the conductors 25. Furthermore, the insulation system 28 is arranged between the stator core 22 and the interconnecting elements 26. The insulation system 28 is a casting. The latter fills the intermediate spaces in the region of the conductors 25 and of the interconnecting elements 26.

[0060] In the cross section in FIG. 8, it is shown that one of the conductors 25 extends beyond the extent of the stator core 22. An electrically insulating material 32 is arranged between the stator core 22 and one of the interconnecting elements 26. The electrically insulating material 32 is arranged on the stator core 22 at the side at which the interconnecting elements 26 are arranged. The insulation system 28 is arranged in the regions of the grooves 23 which are free of the conductors 25. The regions of the grooves 23 in which the insulation system 28 is arranged are visible at the inner side of the stator core 22. The casing 31 is arranged around the stator core 22 and the interconnecting elements 26.

[0061] The conductor 25 shown in a cross-sectional view is connected to the lowermost of the three interconnecting elements 26 shown in cross section. In each case one electrically insulating material 32 is arranged between the interconnecting elements 26. The two interconnecting elements 26 arranged above the lowermost interconnecting element 26 do not extend as far as the conductor 25, and therefore these are not connected to the conductor 25. The intermediate spaces between the stator core 22, the conductors 25 and the interconnecting elements 26 are filled by the insulation system 28.

[0062] A sectional illustration through part of a further exemplary embodiment of the stator 20 is shown in FIG. 9. The only difference from the exemplary embodiment shown in FIG. 8 consists in that the insulation system 28 is used instead of the electrically insulating material 32. This means that the insulation system 28 is arranged between the interconnecting elements 26. Moreover, the insulation system 28 is arranged on the stator core 22 at the side at which the interconnecting elements 26 are arranged. The insulation system therefore electrically insulates the stator core 22 from the interconnecting elements 26. Furthermore, the insulation system 28 electrically insulates the interconnecting elements 26 from one another.

[0063] In FIG. 10, an excerpt from a further exemplary embodiment of the stator 20 is shown. The recesses 27 of the interconnecting elements 26 have a shape for positioning a conductor 25 in the recess 27, respectively. For this purpose, the recesses 27 have the shape of a trapezoid in a cross section through the stator 20, respectively, wherein the cross section is given in a plane which runs perpendicularly to the longitudinal axis of the stator core 22. The conductors 25 also have the shape of a trapezoid in this cross section. Therefore, the conductors 25 can be positioned in a precisely fitting manner in the recesses 27. Moreover, slipping of the conductors 25 in lateral directions x is prevented by the trapezoid-like shape.

[0064] In FIG. 11, an excerpt from a further exemplary embodiment of the stator 20 is shown. In this case, one interconnecting element 26 and a further interconnecting element 29 have an intermeshing shape in places, respectively. At their upper side 33, the interconnecting elements 26 and the further interconnecting elements 29 each have a protrusion 34. At their lower side facing away from the upper side 33, the interconnecting elements 26 and the further interconnecting elements 29 each have a notch 35 which has the shape of the protrusion 34. The interconnecting elements 26 and the further interconnecting elements 29 can be attached to the stator core 22 in such a way that one protrusion 34 is arranged in a notch 35, respectively. Therefore, in each case one interconnecting element 26 and a further interconnecting element 29 engage with one another in places, which increases the stability of the connection of the interconnecting elements 26 and of the further interconnecting elements 29 to one another.

LIST OF REFERENCE SIGNS

[0065] 20: stator
21: electric machine
22: stator core
23: groove
24: electrical winding
25: conductor
26: interconnecting element
27: recess
28: insulation system
29: further interconnecting element
30: rotor
31: casing
32: electrically insulating material
33: upper side
34: protrusion
35: notch
S1, S2, S3: steps
x: lateral direction