DE102021119592A1 - Process for the production of an optimized end winding geometry and coil winding with such a geometry - Google Patents

Abstract

The invention relates to a method for producing a coil winding (100) for insertion into radially open slots in a stator or rotor of an electrical machine, the coil winding (100) having a wire bundle (10) which consists of a number of wires (10a, 10b, 10c), the wires (10a, 10b, 10c) of the wire package (10) running parallel to one another and the coil winding being formed by a flat winding template (20) that can be rotated about an axis of rotation (D) and winding heads (19) with an offset amount (VB) representing oblique areas (12, 16), it being provided for the method that the end winding geometry is produced in such a way that at least one straightened area (14, 15, 18) is present in the end winding (19). The invention also relates to a coil winding (100) which is produced using this method.

Description

The invention relates to a method for producing an optimized winding overhang geometry and a coil winding with such a geometry.

The present method is used to produce a coil winding as a so-called wave winding, which can then be inserted into the slots of a stator or rotor. Such a coil winding or wave winding is also referred to as a bar wave winding.

A wave winding comprises a plurality of parallel wires having straight sections (bars) that are placed in the slots of a stator. When these straight sections alternate between an inner and an adjacent outer radial layer in the stator as the wire pattern moves radially around the stator, it is also referred to as distributed wave winding. The individual wire webs are connected by roof-shaped winding heads, which are outside of the rotor or stator slots. With a wave winding, the wire webs and the winding overhangs are made from a continuous wire. The wave pattern of a wave winding includes X number of phases or grouped slots in the stator. Thus, the wire webs do not necessarily lie in directly adjacent grooves. In general, the number X is a multiple of 3, but constructions are also possible in which X is any other whole number. This results in a spatial offset of the wire webs of an individual wire or within a phase, with this offset between the wire webs or slots being bridged by appropriately designed winding heads.

The use of wave winding as a winding technology offers advantages in the development of high-performance electric motors in terms of maximum performance compared to a concentrated winding and advantages in terms of the number of welds and skin and proximity effects compared to a hairpin design.

A challenge in the design of an electric motor with a wave winding lies in the process of bending the end winding, which combines two bending operations. When bending the winding head geometry, diagonal winding takes place over a rotatable winding form. This creates a purely diagonal roof shape of the wire. Such a procedure is, for example, from DE 10 2015 120 661 A1 known.

In particular when using wires with a substantially rectangular cross section, which are preferred with regard to an optimal degree of filling in the slots of the stator, the edges of the wires tend to stand up during the formation of the end windings in the wave winding. This leads to damage and/or weakened insulation on the wire in the further course of the manufacturing process, for example when the wave winding is transferred into a drawing-in tool or when the wave winding is drawn into a stator or rotor body.

The object of the present invention is to reduce the stress on the individual wires of the winding overhangs during the winding process.

According to the invention, the object is achieved by the method according to claim 1 and the device according to claim 9. Configurations result from claims 2 to 8.

1. a) Zufuhr des für die Spulenwicklung zum Einsatz kommenden Drahtpakets in einer Zufuhrrichtung senkrecht zu der Wickelschablone;
2. b) Halten des Drahtpakets in einem ersten Haltebereich auf der Wickelschablone;
3. c) Halten des Drahtpakets in einem zweiten Haltebereich in einem Abstand vor der Wickelschablone bezogen auf die Zufuhrrichtung;
4. d) Verschieben des zweiten Haltebereichs relativ zu dem ersten Haltebereich in einer Richtung parallel zu der Drehachse der Wickelschablone zur Ausbildung eines gegenüber der Zufuhrrichtung ersten geneigten Drahtabschnitts zwischen dem ersten Haltebereich und dem zweiten Haltebereich um zumindest den halben Versatzbetrag des Wickelkopfs;
5. e) Ausbilden eines zufuhrseitigen ersten begradigten Teilabschnitts des Drahtpakets der parallel zu der Zufuhrrichtung verläuft;
6. f) Drehen der Wickelschablone um 180° um die Drehachse unter Zufuhr des Drahtpakets aus der Zufuhrrichtung, wobei das Drahtpaket in einem dritten Haltebereich auf der dem ersten Haltebereich gegenüberliegenden Seite der Wickelschablone gehalten wird, wodurch sich in dem Drahtpaket ein um die Wickelschablone reichender Biegebereich ausbildet;
7. g) Verschieben des dritten Haltebereichs in einer Richtung parallel zu der Drehachse der Wickelschablone zur Ausbildung eines zweiten gegenüber der Zufuhrrichtung geneigten Drahtabschnitts zwischen dem Biegebereich und dem dritten Haltebereich zur Komplettierung des Wickelkopfs, falls der Versatz des ersten geneigten Drahtabschnitts aus Schritt d) nicht zumindest dem vollen Versatzbetrag des Wickelkopfs entspricht;
8. h) Wiederholen der Schritte a) bis g), wobei der dritte Haltebereich aus Schritt g) der erste Haltebereich aus Schritt b) wird.

For a method of manufacturing a coil winding for insertion into radially open slots of a stator or rotor of an electrical machine, the coil winding having a wire package which consists of a number of wires, the wires of the wire package running parallel to one another and the coil winding through a flat and a winding template rotatable about an axis of rotation is formed and has winding heads with oblique areas representing an offset amount, the following method steps are provided:

1. a) feeding the wire package used for the coil winding in a feed direction perpendicular to the winding template;
2. b) holding the wire package in a first holding area on the former;
3. c) holding the wire bundle in a second holding area at a distance in front of the winding template in relation to the feed direction;
4. d) shifting the second holding area relative to the first holding area in a direction parallel to the axis of rotation of the former to form a wire section that is inclined first relative to the feed direction between the first holding area and the second holding area by at least half the offset amount of the end winding;
5. e) Forming a feed-side first straightened section of the wire bundle which runs parallel to the feed direction;
6. f) Rotating the winding template by 180° around the axis of rotation while feeding the wire package from the feed direction, the wire package being held in a third holding area on the side of the winding template opposite the first holding area, whereby forming a bending area in the wire bundle that extends around the winding template;
7. g) Displacement of the third holding area in a direction parallel to the axis of rotation of the winding template to form a second wire section inclined relative to the feed direction between the bending area and the third holding area to complete the winding overhang if the offset of the first inclined wire section from step d) is not at least corresponds to the full offset amount of the end winding;
8. h) repeating steps a) through g), wherein the third hold of step g) becomes the first hold of step b).

To produce the winding head geometry according to the invention, a number of wires are first guided onto the winding template. The winding template, which is also called the winding sword, can be rotated about an axis of rotation and has two essentially flat sides and low flanks. The wires are held in a holding area on one side of the former. This can be done there, for example, by fixing it using a clamping device. In addition, the wires are held on the feed side next to the winding template in a second holding area. This can also be done there, for example, by a suitable clamping device. According to the method described above, the former is rotated about the axis of rotation, as a result of which a substantially flat wave winding is produced around the former. At the flanks of the former, the wires are bent around the former, creating a bending area over the flank height. The bending area is at the top of the roof-shaped winding heads. The wave winding can be stripped from the winding template either after it has been produced or continuously.

By shifting the holding areas, the inclined wire sections are produced on both sides of the winding template. At the same time, the offset of the wire webs mentioned at the beginning is caused by the diagonal offsetting of the wires and the formation of the winding heads. It is also conceivable that the inclined wire sections are already present in the supplied wire package, as a result of which method steps a to d become obsolete and a correspondingly preformed wire package is supplied instead.

The fact that each wire of the wire package is again aligned perpendicular to the winding form between the two diagonally offset areas advantageously results in a flattening of the tip of the winding overhangs.

According to the prior art, winding heads are designed in such a way that the individual wires are also wound diagonally around the flank area, as a result of which real peaks are produced in the roof-shaped winding heads.

The flattening described above results in the advantage that the wire edges are significantly reduced in this way. The wave winding produced in this way has an advantageous effect particularly when using wires with a rectangular cross section, since such wires tend to stand up with the edges, particularly in the case of a non-parallel bending from one side of the winding template to the other side of the winding template.

Holding devices or fixing devices for holding or fixing the individual wires of the wire package are used in the holding areas. It goes without saying that a specific holding device or fixing device does not have to be present for each holding area, but that three holding areas can also be operated by two holding or fixing devices with corresponding mobility of the holding or fixing devices.

According to a development of the invention, it is provided that the first straightened section is formed on the side of the winding template with the first holding area. It is optionally provided that after the formation of the second wire section that is inclined relative to the feed direction, the third holding area is displaced in a direction parallel to the axis of rotation of the winding template, as a result of which a second straightened section of the wire package is formed between the bending area and the second inclined wire section. In this way, the straightened subsections protrude from the sides of the winding template over the bending area, as a result of which there is advantageously no entanglement of an individual wire in the area that lies around the edge or flank of the winding template. In this way, the undesired standing up of the wire in the tip region of the end winding formed is reduced or avoided.

According to a further embodiment of the invention, it can be provided that the first straightened section forms the bending area. In this case, too, there is advantageously reduced entanglement of the respective individual wire of the wire bundle around the edge or flank of the winding template, which advantageously reduces or avoids standing up of the wire in the tip region of the winding overhang.

Furthermore, it can be provided that the first straightened section and/or the second straightened section are each straightened with a straightening means. The use of a straightening means allows a defined formation of the transition between the respective wire section inclined relative to the feed direction and the respective straightened subsection running parallel to the feed direction. Accordingly, according to an optional development, it is provided that the straightening means is an arrangement of pins that is applied to the winding template before straightening or is moved out of the winding template and the wires of the wire package are parallel to the straightening means by moving the respective holding area around the Feed direction to be aligned.

Furthermore, in one embodiment of the invention it can be provided that the straightening means has grooves running parallel to the feed direction, into which wires of the wire bundle are inserted to form the first straightened section and/or the second straightened section. According to such a variant for the straightening means, the straightened areas can be produced in a defined manner. It is also conceivable that a combination of different straightening means is used. For example, it is conceivable to use pins on one side of the winding template and an alignment means having grooves on another side of the winding template. It is also conceivable to combine different straightening means with one another.

Furthermore, it can be provided that the respective alignment means is part of a holding device positioned in the holding area and can be moved from there to the winding template. This results in the advantage that structurally a relatively simple and exact positioning of the alignment means in relation to the winding template and/or the wire package is possible.

A further development results in the second holding area being offset against the winding template before the winding template is rotated. In this way, the system of the individual wires of the wire package on the winding template and in particular on the flank of the winding template in the bending area is improved. Optionally, a fixing or holding means, which is used in the second holding area, can have a guide for the individual wires of the wire package running on the flank side in the bending area. The individual wires can be formed onto the winding template in the bending area by the contact of the holding area or the fixing or holding means used in the holding area.

The invention also relates to a coil winding produced according to the method described above, having wire webs and winding heads with bending areas and inclined areas, with the invention providing that the winding heads each have a flattening due to the bending areas. According to a preferred embodiment, the winding overhangs also have straightened areas running essentially parallel to the wire webs and straightened bending areas which run essentially perpendicular to the straightened areas. A corresponding configuration of the winding overhang avoids or at least significantly reduces the wire edges of the individual wires standing up.

Further features, details and advantages of the invention result from the wording of the claims and from the following description of exemplary embodiments based on the drawings.

• 1: Einen schematischen, exemplarischen Verfahrensablauf und
• 2: Schematische Ansichten einer Wickelschablone mit einem um die Flanke der Wickelschablone gewickelten Einzeldraht nach dem Stand der Technik;
• 3: Schematische Ansichten einer Wickelschablone mit einem erfindungsgemäß um die Flanke der Wickelschablone gewickelten Einzeldraht; und
• 4: Eine schematische Darstellung einer Spulenwicklung.

In the figures show:

• 1 : A schematic, exemplary procedure and
• 2 1: Schematic views of a winding template with a single wire wound around the flank of the winding template according to the prior art;
• 3 1: Schematic views of a winding template with a single wire wound according to the invention around the flank of the winding template; and
• 4 : A schematic representation of a coil winding.

1 shows a process flow of an embodiment of the method according to the invention.

In a first step I, the wire package 10 consisting of the individual wires 10a, 10b, 10c is moved in the feed direction R perpendicular to the winding template 20 over the winding template 20 and in the first holding area 30 on the winding template 20 and the second holding area 40 next to the winding template 20 held. The winding template 20 can be rotated about the axis of rotation D, which runs in a longitudinal direction of the winding template 20 . The second holding area 40 is spaced apart from the winding template 20 in the feed direction R. The individual wires 10a, 10b, 10c are fixed in the respective holding area 30, 40 by means of a fixing means, not shown in detail.

In step II of the 1 it can be seen that the second holding area 40 is offset parallel to the axis of rotation D and perpendicular to the feed direction R, so that in each individual wire 10a, 10b, 10c a wire that is inclined relative to the feed direction R section 12 is formed. The wire bundle 10 remains held on the winding template 20 in the first holding area 30 .

In step III of the 1 aligning means 60 are applied to the side of the winding template 20 on which the first holding area 30 also lies. Here the straightening means 60 is designed as a pin arrangement which is located in front of the individual wires 10a, 10b, 10c in relation to the offset from step II. In a further step IV, the second holding area 40 is again offset parallel to the axis of rotation D and perpendicular to the feed direction R. The offset takes place in the opposite direction to the offset from step II. In the process, the individual wires 10a, 10b, 10c are bent around the pins of the straightening means 60, so that a first straightened section 14 is formed in the respective individual wire 10a, 10b, 10c, with the straightened section 14 runs parallel to the feed direction R.

In step V off 1 the second holding area is brought into contact with the winding template 20 and the winding template 20 is rotated about the axis of rotation D by 180°. This creates a bending area 15 around the flank 22 (cf. 2 and 3 ) of the winding template 20, see step VI, in which the winding template 20 is shown rotated through 180° and the wire package 10, the individual wires 10a, 10b, 10c of which continue to be fed from the feed direction R, on the side of the opposite side of the first holding area 30 Winding template are fixed in the third holding area 50. Here, too, a fixing means that is not shown in detail is used.

In step VII off 1 pins are applied to the winding template 20 around which the individual wires 10a, 10b, 10c are bent parallel to the axis of rotation D and perpendicular to the feed direction R by offsetting the third bending region 50. In each individual wire 10a, 10b, 10c, a wire section 16 is formed that is inclined relative to the feed direction R, and a second straightened section 18 is formed between this inclined wire section 16 and the bending region 15 (cf. step VIII).

The third holding area 50 is offset against the feed direction R and forms the second holding area 40 for a repeated implementation of the method. Step I follows for the production of a further winding according to the method according to the invention.

2 a) 12 shows a side view of a prior art individual wire wound around a former 20. FIG. It can be seen that the bending area 15 runs diagonally on the flank 22 of the winding template 20 . This is due to the formation of the first inclined wire section 12, which is wound around the axis of rotation D without prior straightening before the winding template 20 is rotated. 2 B shows a schematic top view of the area of the winding template 20 with a single wire wound diagonally around the flank 22 according to the prior art.

3 a) shows a side view of a single wire wound around a winding template 20 according to the invention. The bending area 15 runs perpendicularly on the flank 22 of the winding template 20. This is due to the straightened area 14 produced according to the invention, which is caused by the straightening means 60 and the rearward movement of the second holding area 40 (see 1 , step IV).

3 b) shows two possible variants of wrapping the flank 22 of the winding template 20. The bending area 15 can coincide with the straightened areas 14 and 18, so that the inclined wire sections 12, 16 protrude up to the flank of the winding template. It is also conceivable that the straightened areas 14 and 18 lie on the respective side of the winding template 20 and in between the bending area protrudes around the flank 22 of the winding template 20 . According to both embodiments, an entanglement of the individual wires of the wire package is avoided, as a result of which the wire edges are avoided or at least reduced, particularly in the bending area.

4 shows a wave winding 100 made of individual wires 10a, 10b, 10c with webs 11 and end windings 19 produced according to the method according to the invention. In one exemplary embodiment, the flattened tips are formed by the straightened areas 14, 16, between which the bending area 15 lies. It is of course also conceivable that the bending area 15 as a straightened section of the individual wire 10a, 10b, 10c directly adjoins the inclined wire sections 12, 16 and thus forms the flattened tip.

All features and advantages resulting from the claims, the description and the drawing, including structural details, spatial arrangements and method steps, can be essential to the invention both alone and in various combinations.

In a further conceivable embodiment, for example, it can also be provided that the method is preceded by a preforming step, as a result of which a preformed winding overhang is present at the beginning of a wire bundle according to the method according to the invention, and the method is then carried out according to the steps described above. This has the advantage that the open ends of the individual wires all end on one side of the coil winding produced. The wire package with the preformed end winding is fed into the process in the first step.

Reference List

10

wire package

10a,b,c

wire, single wire

11

web

12

first inclined wire section

14

first straightened section

15

bending range

16

second inclined wire section

18

second straightened section

19

winding head

20

wrapping template

22

flank

30

first holding area

40

second holding area

50

third holding area

60

guideline

100

coil winding, wave winding

D

axis of rotation

R

feed direction

vb

offset amount

QUOTES INCLUDED IN DESCRIPTION

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

Patent Literature Cited

• DE 102015120661 A1 [0005]

Claims (10)

Method for producing a coil winding (100) for insertion in radially open slots of a stator or rotor of an electrical machine, the coil winding (100) having a wire package (10) consisting of a number of wires (10a, 10b, 10c), wherein the wires (10a, 10b, 10c) of the wire package (10) run parallel to one another and the coil winding is formed by a flat winding template (20) that can be rotated about an axis of rotation (D) and end windings (19) with an offset amount (V). has sloping areas (12, 16), with the method steps: a) feeding the wire package (10) used for the coil winding (100) in a feed direction (R) perpendicular to the winding template (20); b) holding the wire package (10) in a first holding area (30) on the winding template (20); c) holding the wire package (10) in a second holding area (40) at a distance in front of the winding template (20) based on the feed direction (R); d) Displacing the second holding area (40) relative to the first holding area (30) in a direction parallel to the axis of rotation (D) of the winding template (20) to form a first inclined wire section (12) relative to the feed direction (R) between the first Holding area (30) and the second holding area (40) by at least half the offset amount (VB) of the end winding (19); e) Forming a feed-side first straightened section (14) of the wire package (10) which runs parallel to the feed direction (R); f) rotating the winding template (20) by 180° about the axis of rotation (D) while feeding the wire package (10) from the feed direction (R), the wire package (10) being in a third holding area (50) on the first holding area ( 30) is held on the opposite side of the winding template (20), as a result of which a bending area (15) extending around the winding template is formed in the wire package (10); g) Displacing the third holding area (50) in a direction parallel to the axis of rotation (D) of the winding template (20) to form a second wire section (16) inclined relative to the feed direction (R) between the bending area (15) and the third holding area ( 50) to complete the end turn (19) if the offset of the first inclined wire section (12) from step d) does not correspond to at least the full offset amount (VB) of the end turn (19); h) repeating steps a) through g), wherein the third holding area (50) from step g) becomes the first holding area (30) from step b). procedure after claim 1 , characterized in that the first straightened section (14) is formed on the side of the former with the first holding area (30). Procedure according to one of Claims 1 until 2 , characterized in that after the formation of the second wire section (16) inclined relative to the feed direction (R), the third holding area (50) is displaced in a direction parallel to the axis of rotation (D) of the winding template (20), whereby a second straightened Section (18) of the wire package (10) is formed between the bending region (15) and the second inclined wire section (16). procedure after claim 1 , characterized in that the first straightened section (14) forms the bending area (15). Method according to one of the preceding claims, characterized in that the first straightened section (14) and/or the second straightened section (18) are each straightened with a straightening means (60). procedure after claim 5 , characterized in that the straightening means (60) is an arrangement of pegs which is applied to the winding template (20) before straightening or moves out of the winding template (20) and the wires (10a, 10b, 10c) of the wire package (10 ) are aligned parallel to the feed direction (R) by the movement of the respective holding area (40, 50) around the aligning means (60). procedure after claim 5 , characterized in that the straightening means (60) has grooves running parallel to the feed direction, wherein wires (10a, 10b, 10c) of the wire bundle (10) for forming the first straightened section (16) and/or the second straightened section (18 ) are introduced. Procedure according to one of Claims 5 until 7 , characterized in that the respective alignment means (60) is part of a holding device positioned in the holding area (30, 50) and can be moved from there to the winding template (20). Method according to one of the preceding claims, characterized in that the second holding area (40) is brought into contact with the winding template (20) before the winding template (20) is rotated. Coil winding (100) made according to one of Claims 1 until 9 , having wire webs (11) and winding heads (19) with bending areas (15) and inclined areas (12, 16), characterized in that the winding heads (19) each have a flattening due to the bending areas (15).

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