Stator of an electric machine

Abstract

The invention relates to a stator (1) of an electric machine (2), which stator comprises a stator body (3) having a stator axis (3.1), and an electrical stator winding (4), wherein stator teeth (5) are formed on the stator body (3) and stator slots (6) are formed between the stator teeth (5), wherein the stator body (3) comprises stator discs (7), in particular laminations, for forming a laminated core and / or cover discs, wherein the stator winding (4) comprises multiple interconnected conductor elements (8), wherein, in the stator slots (6), pairs (9) of conductor ends (8e) of a plurality of conductor elements (8) are electrically contacted at a contact point (10) in the relevant stator slot (6) to form contact connections (11), in that respective contact faces (12) of the pairs (9) of conductor ends (8e) are brought into contact by means of contact forces (13), characterised in that the contact connections (11), in particular the contact forces (13) for forming the contact connections (11), are generated by twisting at least one of the stator discs (7) of the stator body (3), in particular individual stator discs (7) or one or more groups (14) of stator discs (7).

Description

[0001] Description

[0002] title

[0003] Stator of an electrical machine

[0004] State of the art

[0005] The invention is based on a stator of an electrical machine according to the preamble of the main claim.

[0006] A stator of an electrical machine is already known from EP3138184 B1, which has a stator body with a stator axis and an electrical stator winding, wherein stator teeth are formed on the stator body and stator slots are formed between the stator teeth, wherein the stator body comprises stator disks to form a laminated core, wherein the stator winding has a plurality of interconnected conductor elements, wherein in the stator slots, pairs of conductor ends of several conductor elements are electrically contacted at a contact point in the respective stator slot to form contact connections, in that contact surfaces of the pairs of conductor ends are brought into contact by means of contact forces. The contact forces are generated by wedging the conductor ends of the respective conductor elements in the stator slots.Due to cumulative tolerances per contact connection, it is difficult to produce high-quality contact connections reproducibly.

[0007] Advantages of the invention

[0008] The stator of an electrical machine according to the invention with the characterizing features of the main claim has the advantage that the production of the stator winding is improved and / or simplified in that the contact connections, in particular the contact forces for forming the contact connections, are generated by rotating at least one of the stator disks of the stator body, in particular individual stator disks or one or more groups of stator disks. The stator winding according to the invention can thus be produced without materially bonding, for example without welding the conductor elements. Furthermore, the stator winding can be formed from preformed conductor elements and plugged together, so that interlacing of the conductor elements during production of the stator winding can be eliminated.

[0009] The measures listed in the subclaims enable advantageous further developments and improvements of the stator of an electrical machine specified in the main claim.

[0010] It is particularly advantageous if the twisted stator discs are located in the axial area of ​​the respective contact point and, with their tooth flanks in the circumferential direction, exert at least indirect pressure on the contact surfaces to ensure mutual contact between the contact surfaces of the respective contact connection. In this way, the stator discs generate clamping contact forces to establish the contact connections.

[0011] It is also advantageous if the conductor ends of at least one of the contact connections are connected in a form-fitting manner. This allows sufficiently large contact surfaces to be created for the contact connections.

[0012] It is very advantageous if, according to a first embodiment, one of the two conductor ends of the respective contact connection has a recess, in particular a notch, and the other conductor end of the contact connection has a projection, in particular a square pin, projecting into the recess of one conductor end, wherein the recess and projection of the respective contact connection have corresponding contact surfaces. In this way, a very simple and easy-to-assemble plug-in connection is achieved as a contact connection. The square projection of the respective conductor end of the respective conductor pair can have parallel or angled contact surfaces.

[0013] It is also advantageous if the recess of one conductor end of the respective contact connection is longer in the axial direction relative to the stator axis than the projection of the other conductor end of the respective contact connection, thereby forming a compensation gap. In this way, tolerances that influence the respective contact connection, for example, the width of the stator slot, the width of the conductor cross-section of the conductor element, or the thickness of the lacquer insulation of the conductor elements, can be compensated.Furthermore, it is advantageous if, according to a second exemplary embodiment, both conductor ends of the respective contact connection each have a projection or a recess, and that an additional connecting element is provided as the third contact partner of the respective contact connection, which connects the two conductor ends of the respective contact connection to one another, in particular by enclosing the two projections or by arranging them in the two recesses of the two conductor ends, and which is in particular sleeve-shaped or pin-shaped or peg-shaped. In this way, large contact surfaces can be achieved. In addition, a plastic deformation of the three contact partners can be generated during production of the contact connections, as a result of which the clamping contact forces to be applied by the stator disks can be made lower.

[0014] Furthermore, it is advantageous if a material-bonded joining agent, in particular a soft solder or a coating comprising silver and / or nickel, is provided between the contact partners of the respective contact connection, in particular in the compensation gap or on the additional connecting element. In this way, in addition to the positive and frictional connection, a material bond can be achieved between the conductor ends of the respective contact connection, thereby reducing the contact resistance between the conductor ends or improving the electrical conduction between the conductor ends. The material bond is formed by heating the stator to a temperature above the softening temperature of the joining agent during production.

[0015] It is advantageous if the contact surfaces of the respective contact connection are parallel or quasi-parallel to the tooth flanks of the respective stator slot. In this way, the contact connection can be designed as a plug-in connection. After the pairs of conductor ends are axially connected, the contact surfaces of the respective contact connections are pressed against each other by means of the twisted stator disks.

[0016] It is also advantageous if an additional element for generating additional contact force, particularly a spring element or a crimp element, is provided in the respective stator slot. This ensures that the total contact forces of the respective contact connection are maintained permanently and at a sufficient level throughout the service life of the stator.

[0017] It is further advantageous if a slot insulation, particularly a sleeve-shaped or cuff-shaped insulation, is provided in the area of ​​the contact points between the respective stator slot and the conductor elements located in the stator slot. This prevents the stator disks, which are rotated to form the contact connection, from damaging the insulation of the conductor elements due to the contact forces they exert. This ensures that the stator body remains electrically insulated from the stator winding.

[0018] Advantageously, the conductor elements of the stator winding are formed from flat or rectangular wire and each have a rectangular conductor cross-section.

[0019] It is also advantageous if the twisted stator disks, in particular sheet metal laminations, are fixed in the stator body, in particular by welding the twisted stator disks to adjacent stator disks or by a press fit between the stator body and a stator housing, which, for example, encloses the stator. This ensures that the contact forces can be maintained permanently.

[0020] According to an advantageous embodiment, the stator winding is divided in the axial direction with respect to the stator axis into at least two winding parts, each winding part being formed from a plurality of conductor elements, wherein conductor ends of one winding part are each contacted with one of the conductor ends of another winding part, forming one of the contact connections, in particular force-fittingly by rotating the specific stator disks. By rotating the stator disks according to the invention, many contact connections are thus established within the stator slots in one go. The winding parts of the stator winding can thus be plugged together in the axial direction and electrically connected to the stator winding by rotating the stator disks according to the invention, forming a plurality of the contact connections according to the invention.This can be achieved, in particular, without materially bonding the conductor elements of the winding parts, for example, without welding. Furthermore, the invention relates to an electrical machine with a stator according to the invention.

[0021] drawing

[0022] Embodiments of the invention are shown in simplified form in the drawing and explained in more detail in the following description.

[0023] Fig.l shows a stator of an electrical machine with stator disks rotated according to the invention for the non-positive electrical contacting of pairs of conductor ends within the stator slots of the stator,

[0024] Fig.2 is a sectional view of a single stator slot of the stator according to Fig.l,

[0025] Fig.3 is a view of a detail X according to Fig.2 according to a first embodiment,

[0026] Fig.4 is a view of the detail X of Fig.2 according to a second embodiment,

[0027] Fig.5 is a view of the detail X of Fig.2 according to a third embodiment,

[0028] Fig.6 shows a pair of conductor ends according to the invention for forming one of the contact connections according to a first embodiment of the first embodiment,

[0029] Fig.7 shows a pair of conductor ends according to the invention for forming one of the contact connections according to a second embodiment of the first embodiment,

[0030] Fig.8 shows a pair of conductor ends according to the invention for forming one of the contact connections according to a third embodiment of the first embodiment and

[0031] Fig. 9 shows a pair of conductor ends according to the invention with an additional element for generating an additional contact force. Description of the embodiments

[0032] Fig.l shows a partial view of a stator of an electrical machine with stator disks rotated according to the invention for the non-positive electrical contacting of pairs of conductor ends within the stator slots of the stator.

[0033] The stator 1 of an electrical machine 2 according to the invention comprises a stator body 3 and an electrical stator winding 4. Stator teeth 5 are formed on the stator body 3, and stator slots 6 are formed between the stator teeth 5. The stator body 3 comprises stator disks 7, in particular laminations made of electrical sheet metal for forming a laminated core and / or other disks, for example cover disks.

[0034] The stator disks 7 shown in Fig.l and Fig.2 are shown comparatively thick for illustration reasons and can each also comprise a group of stator disks, in particular sheet metal laminations.

[0035] The stator winding 4 comprises a plurality of interconnected conductor elements 8.

[0036] In the stator slots 6, pairs 9 of conductor ends 82 of a plurality of conductor elements 8 are electrically contacted at a contact point 10 in the respective stator slot 6 to form contact connections 11, in which contact surfaces 12 of the pairs 9 of conductor ends 8e are brought into contact by means of contact forces. After the formation of the contact connections 11, either a single electrical conductor per stator slot 6 or a conductor bundle comprising several electrical conductors can be present in the stator slots 6. The conductors of the conductor bundle lie one above the other in the radial direction with respect to a stator axis 3.1, as shown in Fig. 1.

[0037] The conductor elements 8 of the stator winding 4 are formed, for example, from flat or rectangular wire and each have a rectangular conductor cross-section. Furthermore, the conductor elements 8 of the stator winding 4 can each have, for example, a varnish insulation 8i.

[0038] To illustrate the invention, Fig. 1 shows the stator winding 4 only in one of the stator slots 5. The stator winding 4 forms a winding head 4.1 on each of the two end faces of the stator body 3. Fig. 2 shows a sectional view of a single stator slot 6 of the stator 1 according to Fig. 1.

[0039] Fig.3 shows a view of a detail X according to Fig.2 according to a first embodiment.

[0040] According to the invention, the contact connections 11, in particular the contact forces for forming the contact connections 11, are generated by rotating at least one of the stator disks 7 of the stator body 3, in particular individual stator disks 7 or one or more groups of stator disks 7. The contact connections 11 can, as shown in Fig.3 to Fig.5, be generated by opposite rotation of stator disks 7 or groups 14 of stator disks 7. The rotation of the stator disks 7 takes place by a rotation angle <|) around the stator axis 3.1.

[0041] The twisted stator disks 7 are fixed in the stator body 3, in particular by welding the twisted stator disks 7 to adjacent stator disks 7 or by a press fit between the stator body 3 and a stator housing surrounding the stator body 3.

[0042] The stator winding 4 can be divided in the axial direction relative to the stator axis 3.1 into at least two winding parts in a manner not shown, wherein each winding part is formed from a plurality of conductor elements 8. According to the invention, the conductor ends 8e of one winding part can each be contacted with one of the conductor ends 8e of another winding part, forming one of the contact connections 11, in particular in a force-fitting manner by rotating the specific stator disks 7.

[0043] The rotated stator disks 7 are located in the axial region of the respective contact point 10 with respect to the stator axis 3.1 and press with tooth flanks 7.1 in the circumferential direction with respect to the stator axis 3.1 at least indirectly on the contact surfaces 12 for mutual contacting of the contact surfaces 12 of the respective contact connection 11. The contact points 10 of the pairs of conductor ends 8e located in the same stator slot 6 and their contact connections 11 can be located in the respective stator slot 6 at the same or at different axial positions.

[0044] The conductor ends 8e of at least one of the contact connections 11 are plugged together in pairs in a form-fitting manner.

[0045] The contact surfaces 12 of the respective contact connection 11 are formed parallel or quasi-parallel to tooth flanks 4.1 of the respective stator slot 4. After the pairs of conductor ends 8e are axially connected, the contact surfaces 12 of the respective contact connections 11 are pressed against each other by means of the rotated stator disks 7.

[0046] According to the first exemplary embodiment, one of the two conductor ends 8e of the respective contact connection 11 has a recess 16, in particular a notch, and the other conductor end 8e of the contact connection 11 has a projection 17, in particular a square pin, projecting into the recess 16 of one conductor end 8e. The recess 16 and the projection 17 of the respective contact connection 11 have corresponding contact surfaces 12. In this case, the recess 16 of one conductor end 8e of the respective contact connection 11 can be longer in the axial direction with respect to the stator axis 3.1 than the projection 17 of the other conductor end 8e of the respective contact connection 11, thereby forming a compensation gap 18.

[0047] In the area of ​​the contact points 10, a slot insulation 21 can be provided between the respective stator slot 6 and the conductor elements 8 located in the respective stator slot 6, which is in particular sleeve-shaped or cuff-shaped.

[0048] Fig.4 shows a view of the detail X of Fig.2 according to a second embodiment.

[0049] According to the second embodiment, both conductor ends 8e of the respective contact connection 11 each have a projection 17. In addition, an additional connecting element 19 is provided as a third contact partner of the respective contact connection 11, which connects the two conductor ends 8e of the respective contact connection 11 to one another, in particular by enclosing the two projections 17 in a sleeve-like manner.

[0050] Fig.5 shows a view of the detail X of Fig.2 according to a third embodiment.

[0051] According to the third exemplary embodiment, both conductor ends 8e of the respective contact connection 11 each have a recess 16. In addition, an additional connecting element 19 is provided as a third contact partner of the respective contact connection 11, which connects the two conductor ends 8e of the respective contact connection 11 to one another, in particular by arranging or projecting the connecting element 19 into the two recesses 16 of the two conductor ends 8e. The additional connecting element 19 is pin- or peg-shaped according to the third exemplary embodiment.

[0052] Between the contact partners 8e, 19 of the respective contact connection 11, in particular in the compensation gap 18 or on the additional connecting element 19, a material-locking joining agent, in particular a soft solder or a coating comprising silver and / or nickel, can be provided in order to be able to produce a material-locking connection in addition to the positive and non-positive connection according to the invention.

[0053] Fig.6 shows a pair of conductor ends according to the invention for forming one of the contact connections according to a first embodiment of the first exemplary embodiment.

[0054] According to the first embodiment, the projection 17 of one conductor end 8e, which is designed as a square, offset pin, is completely enclosed by the other conductor end 8e after being inserted into the recess 16 of the other conductor end 8e and is therefore no longer visible.

[0055] Fig. 7 shows a pair of conductor ends according to the invention for forming one of the contact connections according to a second embodiment of the first exemplary embodiment. According to the second embodiment, the recess 16 of one conductor end 8e is designed as a notch that is continuous in the direction of a height or width of the conductor end 8e. For example, the recess 16 forms a fork-shaped conductor end 8e. The projection 17 of the other conductor end 8e, designed as a square tenon, is inserted between the prongs 15 of the fork-shaped conductor end 8e to produce a tenon-shaped or shear-tenon-shaped (conceptually based on wood joints or wooden beam joints) contact connection 11.The notch 16 and the pin 17 can be correspondingly wedge-shaped so that the contact connection 11 can absorb an axial pull-out force against unwanted separation of the contact connection 11 after the contact forces have been generated by rotating the stator disks 7.

[0056] As an alternative to the tenon joint or shear tenon, the conductor ends of the respective pair of conductor ends can also form a so-called straight blade, conceptually based on wood joints or wooden beam joints.

[0057] Fig.8 shows a pair of conductor ends according to the invention for forming one of the contact connections according to a third embodiment of the first embodiment

[0058] According to the second design, the contact connection is designed in the shape of a tenon blade.

[0059] Fig.9 shows a pair of conductor ends according to the invention with an additional element for generating an additional contact force.

[0060] In the stator slots 6, in the area of ​​the contact points 10, an additional element 20 can be provided to generate an additional contact force pressing the contact surfaces 12 together. This additional element 20 is, in particular, a spring element or a crimp element and is designed, for example, in a sleeve-shaped or clamp-shaped manner. The additional element 20 can, for example, bite into the material of the conductor ends 8e with points 20.1.

Claims

Claims 1. Stator (1) of an electric machine (2), comprising a stator body (3) with a stator shaft (3.1) and an electric stator winding (4), wherein stator teeth (5) are formed on the stator body (3) and stator slots (6) are formed between the stator teeth (5), wherein the stator body (3) comprises stator disks (7), in particular sheet metal laminations for forming a laminated core and / or cover disks, wherein the stator winding (4) comprises a plurality of interconnected conductor elements (8), wherein pairs (9) of conductor ends (8e) of several conductor elements (8) are electrically contacted at a contact point (10) in the respective stator slot (6) to form contact connections (11), by bringing contact surfaces (12) of the pairs (9) of conductor ends (8e) into contact by means of contact forces (13), characterized in that the contact connections (11), in particular the contact forces (13) for forming the contact connections (11)are generated by twisting at least one of the stator disks (7) of the stator body (3), in particular individual stator disks (7) or one or more groups (14) of stator disks (7).

2. Stator according to claim 1, characterized in that the twisted stator disks (7) lie in the axial area of ​​the respective contact point (10) and press at least indirectly with tooth flanks (7.1) in circumferential direction onto the contact surfaces (12) for mutual contacting of the contact surfaces (12) of the respective contact connection (11).

3. Stator according to one of the preceding claims, characterized in that the conductor ends (8e) of at least one of the contact connections (11) are positively connected.

4. Stator according to one of the preceding claims, characterized in that one of the two conductor ends (8e) of the respective contact connection (11) has a recess (16), in particular a notch, and the other conductor end (8e) of the contact connection (11) has a projection (17), in particular a square pin, projecting into the recess (16) of one conductor end (8e). wherein the recess (16) and the projection (17) of the respective contact connection (11) have corresponding contact surfaces (12).

5. Stator according to claim 4, characterized in that the recess (16) of one conductor end (8e) of the respective contact connection (11) is longer in the axial direction with respect to the stator axis (3.1) than the projection (17) of the other conductor end (8e) of the respective contact connection (11), thereby forming a compensating gap (18) in each case.

6. Stator according to one of claims 1 to 5, characterized in that both conductor ends (8e) of the respective contact connection (11) each have a projection (17) or each have a recess (16) and that an additional connecting element (19) is provided as a third contact partner of the respective contact connection (11), which connects the two conductor ends (8e) of the respective contact connection (11) to each other, in particular by enclosing the two projections (17) or by arranging them in the two recesses (16) of the two conductor ends (8e), and which is in particular designed in a sleeve-like or pin- or peg-like form.

7. Stator according to one of the preceding claims, characterized in that a material-bonding joining agent, in particular a soft solder or a coating comprising silver and / or nickel, is provided between the contact partners (8e, 19) of the respective contact connection (11), in particular in the compensation gap (18) or on the additional connecting element (19).

8. Stator according to one of the preceding claims, characterized in that the contact surfaces (12) of the respective contact connection (11) are formed parallel or quasi-parallel to tooth flanks (5.1) of the respective stator groove (6).

9. Stator according to one of the preceding claims, characterized in that an additional element (20) for generating an additional contact force is provided in the respective stator groove (6), which is in particular a spring element or a crimp element.

10. Stator according to one of the preceding claims, characterized in that in the area of ​​the contact points (10) between the respective stator slot (6) and the conductor elements (8) lying in the stator slot (6) a slot insulation (21) is provided, which is in particular sleeve-shaped or cuff-shaped. Stator according to any one of the preceding claims, characterized in that the conductor elements (8) of the stator winding (4) are formed from flat or rectangular wire and each has a rectangular conductor cross-section. Stator according to any one of the preceding claims, characterized in that the twisted stator disks (7) are fixed in the stator body (3), in particular by welding the twisted stator disks (7) to adjacent stator disks (7) or by an interference fit between the stator body (3) and a stator housing. Stator according to any one of the preceding claims, characterized in that the stator winding (4) is axially oriented with respect to the stator axis (3).1) is divided into at least two winding sections, each winding section being formed from a plurality of conductor elements (8), wherein conductor ends (8e) of one winding section are contacted with one of the conductor ends (8e) of another winding section, forming one of the contact connections (11), in particular by frictional connection through rotation of the respective stator disks (7). Electrical machine (2) with a stator (1) according to one of the preceding claims.

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