Patent Publication Number: US-11394281-B2

Title: Method for manufacturing a coil mat from wave winding wires by plugging

Description:
CROSS-REFERENCES TO RELATED APPLICATIONS 
     This application claims the benefit of the International Application No. PCT/DE2019/100179, filed on Feb. 27, 2019, and of the German patent application No. 102018001553.0 filed on Feb. 28, 2018, and of the German patent application No. 102018009460.0 filed on Dec. 5, 2018, the entire disclosures of which are incorporated herein by way of reference. 
     FIELD OF THE INVENTION 
     The invention relates to a method and a device for manufacturing a wave winding mat composed of wave winding wires. In the following, such a wave winding mat is simply referred to as a winding mat. The invention further relates to a method and device for manufacturing a coil mat composed of a first individual mat formed as a winding mat and a second individual mat formed as a winding mat. 
     BACKGROUND OF THE INVENTION 
     The invention relates to methods and devices for manufacturing winding mats composed of wave winding wires for manufacturing a coil winding of an electric machine. A winding mat is understood to be a mat-shaped conductor bundle formed from several wave winding wires (conductors). Wave winding wires are wires bent in a wave shape. The bend in one plane can be achieved by bending successive wire sections in opposite bending directions. This production method is particularly advantageous for profile wires having a cross-sectional profile shape that deviates from a round shape, for example a rectangular profile. The windings from wave winding wires and winding mats are different from so-called sword windings in which a coil winding is created by winding the winding wires on an elongate rectangular form (sword), and from the resulting (sword) winding mats in that the wires are not bent spirally or helically, but are bent flat. A winding mat comprises, in particular, several wave winding wires extending in a longitudinal direction and bent in a wave shape. Said wave winding wires have straight wire sections spaced apart in the longitudinal direction and extending in a transverse direction running transversely to the longitudinal direction, and intermediate roof-shaped winding heads such that adjacent straight wire sections are connected to each other by a winding head bent in a roof shape. 
     The straight wire sections of the winding mat are specifically intended to be inserted into slots of a housing of an electric machine component, such as, in particular, a stator of an electric motor. The winding heads each make a turnaround and protrude on the outside of the axially directed ends of the housing, connecting the wire section of one slot to a wire section in another slot. All in all, the coil winding of the component of the electrical machine can thus be formed by one or preferably several winding mats. For example, a three-phase coil winding is to be produced. 
     In the following, some terms which are used in the description of the invention and its advantageous designs and also in the discussion of the technological background will be explained in more detail with reference to the illustrations in  FIGS. 34 and 35 .  FIGS. 34 and 35  show a simplified representation of a sub-segment of a housing  10  of a stator  14  with slots  16  and a coil winding  20  formed from conductors A, B, the stator in this case being an exemplary component  12 .  FIG. 34  shows a single-layer winding where the conductors A and B remain in one plane, and  FIG. 35  shows a two-layer winding where the conductors A and B swap plane. 
     Coil step/coil width: The “coil step” SPS specifies by how many slots  16  a single conductor A, B jumps per turnaround. The average coil step SPS of coil the winding  20  is called “coil width”. The coil step and the coil width may differ, for example, if two single conductors of the same phase run parallel. In  FIG. 34 , it can be seen that conductor B has a coil step SPS of five. The outer conductor A jumps seven slots. This gives a coil width of six. 
     Shift measure: The “shift measure” is the dimension of the coil width. This is diameter-dependent, since the circumferential distance between the slots  16  of the stator  14  increases as the diameter increases. If a winding mat has several turns in the stator  14 , it has several shift measures, but a constant coil width. 
     Zone width: The “zone width” indicates the number of slots from which a winding scheme is repeated. If the coil step is constant, the “zone width” corresponds to the coil width. If the coil step SPS changes each time at a coil width of six, the scheme is repeated after the second turnaround. This gives a zone width of twelve. 
     Conductor swap: If a winding scheme has these differences in the coil step, one speaks of a winding with “conductor swap”. If one looks at the sequence of the conductors A, B in  FIG. 34  in the circumferential direction, one can see that always two conductors are swapped (AB-&gt;BA). 
     Layer swap: If, as in  FIG. 35 , two conductors A, B swap planes in the slot  16  or in a winding mat, this is called “layer swap”. At the point where the conductors A, B swap plane, they have a jump  22 . A winding mat without layer swap is also called a “single-layer winding mat”, a winding mat with layer swap is called a “two-layer winding mat”. Swapping the layers can also compensate for potential differences in the conductors which would result from a different distance between the two layers and another component of the electrical machine, such as the rotor. 
     WO2016/072480 A1 and the corresponding DE 11 2015 005047 A1 describe a flat-wound interlaced winding mat with layer swap at several points, produced by interlacing/twisting into each other, where a layer swap can never occur directly after six slots, but can occur after twelve, eighteen, twenty-four slots, etc. A layer swap is possible on both sides of the core stack—housing of the stator. There are two winding head shapes of the winding heads with mirrored height offsets and with sections in the winding head displaced upwards and downwards. This means that the winding heads fit into each other when rolled up. 
     From JP 2002 176 752 A and the corresponding DE 601 25 436 A1, a winding mat is known designed as a sword winding mat created from individual wires wound in a sword winding style and used to form a coil winding of a stator of an electric motor, which coil winding is executed by sword winding and thus has no wave winding wires. A winding head shape of the winding heads with two flat winding head sections and one jump is described. 
     DE 10 2004 056 811 A1 describes a winding mat connected in parallel, with continuous layer swap. 
     DE 10 2014 111 803 A1 describes a stepped winding mat with a conductor swap at the stair. 
     WO 2016/139 430 A1 describes a slot assignment for a winding mat. The winding mat is introduced in several steps. 
     U.S. Pat. No. 6,882,077 A describes a general winding mat having winding heads with two inclined elements and one jump. 
     WO 2006/107 993 A1 and the corresponding DE 11 2006 000 742 A1 describe a winding mat with a coil step of 5-7 in one plane and a winding comprising six conductors. At least 50% of the jumps of 5-7 of the coil steps are in one layer and two conductors are in parallel. 
     WO 2007/080353 A1 (corresponds to U.S. Pat. No. 8,393,072 A and EP 1 974 443 A1) discloses a winding mat with layer swap, but without conductor swap, hence without a coil step of 5-7. To create the winding mat, individual wires or individual winding mats must be interlaced. 
     WO 2006/067298 A1 describes different winding schemes of flat-wound mats with a coil width of 6. 
     DE 103 59 863 A1 describes the variation of a winding head height with jumps in the winding head. 
     WO2016/072480 A1 and the corresponding DE 11 2015 005 047 A1 describe a winding head shape also having three bend points and with different jump heights. 
     DE 11 2006 000 742 A1 describes a winding head shape having two bend points and equal jump heights. 
     SUMMARY OF THE INVENTION 
     The invention is based on an object of providing methods and devices for manufacturing a winding mat and a coil mat formed from this winding mat, which methods and devices can be more easily automated for large series production than previously and enable the production of coil winding of an electric machine more easily and with increased reliability. 
     Preferred designs of the winding mat manufacturing method can be used to produce a winding mat for forming a coil winding of a component of an electrical machine, comprising several wave winding wires extending (in an elongate manner) in a longitudinal direction and bent in a wave shape, said wave winding wires having straight wire sections longitudinally spaced apart and extending in a transverse direction running transversely to the longitudinal direction, and intermediate roof-shaped winding heads such that adjacent straight wire sections are connected to each other by a winding head bent in a roof-shaped manner to form a half-wave section in such a manner that first half-wave sections with first winding heads bent in a first direction and second half-wave sections with second winding heads bent in an opposite second direction are alternately provided and a first half-wave section and an adjacent second half-wave section respectively form a wave section, 
     wherein the wave winding wires are not interlaced or twisted, but are joined together by plugging the wave winding wires together in the transverse direction to one another in such a way that at at least one insertion region of the winding mat, a first and an adjacent second sub-section of the one wave winding wire and a first and an adjacent second sub-section of the other wave winding wire are plugged into each other in such a way that the first sub-section of the one wave winding wire is plugged-in under the first sub-section of said other wave winding wire and the second sub-section of the one wave winding wire is plugged-in over the second sub-section of the other wave winding wire. 
     It is preferred that the winding heads each have a central roof bend and a transition bend in the transition region to the associated straight wire sections and a counter-bend between the transition bends and the roof bend. 
     According to a first variant, it is preferred that the winding mat is designed in a flat manner with a uniform extension in height direction over the entire length. 
     According to a second variant, it is preferred that the winding mat is designed stepped in a stair-like manner, where at least one transition region forms a step in the height direction and the transition region preferably forms a plug-in region. 
     It is preferred that a start region and/or an end region of the winding mat form the at least one plug-in region where the or at least two of the wave winding wires are plugged into each other. 
     It is preferred that the or at least two of the wave winding wires are plugged into each other at a start region of the winding mat and/or at an end region of the winding mat and are stacked in at least one intermediate region. 
     It is preferred that one pair or a group of wave winding wires are respectively plugged into another pair or group of wave winding wires. 
     It is preferred that only a subgroup of wave winding wires are inserted into each other in the winding mat and remaining wave winding wires are stacked. 
     It is preferred that each wave winding wire in the straight wire sections has a wire thickness which, measured in a height direction running transversely to the longitudinal direction and transversely to the transverse direction, extends over a wire thickness dimension. 
     It is preferred that each winding head has a first height offset by half a height extension dimension at a first winding head section connecting to a first straight wire section, a second height offset by a full height extension dimension at a second winding head section connecting to the first winding head section, and a third height offset by half a height extension dimension at a third winding head section extending between the second winding head section and a second straight wire section. 
     It is preferred that the height extension dimension is equal to the wire thickness dimension or equal to the wire thickness dimension plus a predetermined tolerance. 
     Preferably, the height extension dimension is dependent on the wire thickness. In particular, the height dimension is dependent on the wire thickness dimension. Preferably, the height extension dimension results from the wire thickness plus a tolerance that takes into account a play/clearance to the wire below/next to it as well as other distances selected for design reasons. The height extension dimension indicates how high the jump in the winding heads is. The tolerance by which the height extension dimension is greater than the wire thickness dimension, is preferably much smaller than the wire thickness dimension and is, for example, in a range of 0.001% to 5% of the wire thickness. Preferably, typical tolerance values are taken into account in the tolerance such that adjacent wires lie on each other without tension and there is preferably a small clearance between adjacent wires lying on each other. 
     It is further preferred that at least one standard region is provided where the first height offset is directed in a first height direction, the second height offset is directed in the opposite second height direction, and the third height offset is directed in the first height direction at each winding head. 
     It is further preferred that in a transition region of a winding mat according to the second variant, at least one winding head where the first height offset is directed in the first height direction, the second height offset is directed in the first direction, and the third height offset is directed in the second direction, and at least one winding head where the first height offset is directed in the second height direction, the second height offset is directed in the second height direction, and the third height offset is directed in the first height direction, are provided at each of the wave winding wires. 
     It is further preferred that in a start region and/or end region of the winding mat, at least one winding head is provided in each case at the wave winding wires, where
         the first height offset is directed in the first height direction, the second height offset is directed in the second height direction, and the third height offset is directed in the first height direction or   the first height offset is directed in the second height direction, the second height offset is directed in the first height direction, and the third height offset is directed in the first height direction.       

     According to a further aspect, the invention provides a coil mat for forming a coil winding of a component of an electric machine, the coil mat comprising a first individual mat having 3n1 individual wave winding wires, where n1 is a natural number greater than 0, and a second individual mat having 3n2 individual wave winding wires, where n2 is a natural number greater than 0, the wave winding wires comprising straight wire sections spaced apart in the longitudinal direction of the coil mat and extending in a transverse direction running transversely to the longitudinal direction, and intermediate roof-shaped winding heads such that adjacent straight wire sections are connected to each other by a winding head bent in a roof-shaped manner and thus form half-wave sections in such a manner that first half-wave sections with first winding heads bent in a first direction and second half-wave sections with second winding heads bent in an opposite direction are alternately provided and a first half-wave section and an adjacent second half-wave section respectively form a wave section, wherein 
     a) at least one of the individual mats is a winding mat according to one of the above designs and/or 
     b) the individual mats are not interlaced or twisted, but are joined together by plugging the individual mats together in the transverse direction to each other in such a way that at at least one insertion region of the coil mat, a first and an adjacent second sub-section of the one individual mat and a first and an adjacent second sub-section of the other individual mat are plugged into each other in such a way that the first sub-section of the one individual mat is pushed under the first sub-section of the other individual mat and the second sub-section of the one individual mat is pushed over the second sub-section of the other individual mat. 
     It is preferred that in the straight sections, each wave winding wire has a wire thickness which, measured in a height direction running transversely to the longitudinal direction and transversely to the transverse direction, extends over a wire thickness dimension, and that each winding head has a first height offset by half a height extension dimension at a first winding head section connecting to a first straight wire section, a second height offset by a full height extension dimension at a second winding head section connecting to the first winding head section, and a third height offset by half a height extension dimension at a third winding head section extending between the second winding head section and the second straight wire section, the height extension dimension being equal to the wire thickness dimension or equal to the wire thickness dimension plus a predetermined tolerance. 
     It is referred that the individual mats are stepped in a stair-like manner, with at least one transition region forming a step in the height direction, 
     that the coil mat has a start region, several standard regions with a respective intermediate transition region, and an end region, 
     that, when the coil mat is used as intended, the first height direction in the height offsets of the winding heads corresponds to a direction radially outwards and the second height direction corresponds to a direction radially inwards, 
     that the winding heads have a winding head shape which is selected from a group of winding head shapes comprising: 
     a first winding head shape where the first height offset is directed in the second height direction, the second height offset is directed in the first height direction and the third height offset is directed in the second height direction, 
     a second winding head shape where the first height offset is directed in the first height direction, the second height offset is directed in the second height direction and the third height offset is directed in the first height direction, 
     a third winding head shape where the first height offset is directed in the first height direction, the second height offset is directed in the first height direction and the third height offset is directed in the second height direction, 
     a fourth winding head shape where the first height offset is directed in the first height direction, the second height offset is directed in the second height direction and the third height offset is directed in the second height direction, 
     a fifth winding head shape where the first height offset is directed in the second height direction, the second height offset is directed in the first height direction and the third height offset is directed in the first height direction; and 
     a sixth winding head shape where the first height offset is directed in the second height direction, the second height offset is directed in the second height direction and the third height offset is directed in the first height direction, 
     and that winding heads with the first or the second winding head shape are provided in said standard regions and that at least some of the wave winding wires in the transition region have winding heads with the third and/or the fourth and/or the fifth and/or the sixth winding head shape. 
     It is preferred that the first and the second individual mats are stacked on one another and that 
     in the first individual mat,
         in the start region and in the standard regions, the winding heads have the second winding head shape; in the transition region, the winding heads of at least one wave winding wire or group of wave winding wires have the fourth winding head shape and the winding heads of at least one other wave winding wire or group of wave winding wires have the sixth wave winding shape; and at the end region, the winding heads of the at least one wave winding wire or group of wave winding wires have the fourth winding head shape; and       

     in the second individual mat, 
     in the start region, the winding heads of at least one wave winding wire or group of wave winding wires have the fourth winding head shape; in the standard regions and in the end region, the winding heads have the first winding head shape; and in the transition region, the winding heads of the at least one wave winding wire or group of wave winding wires have the fourth winding head shape and the winding heads of at least one other wave winding wire or group of wave winding wires have the sixth wave winding shape. 
     It is preferred that the first and the second individual mats are stacked on one another and that 
     in the first individual mat,
         in the start region and in the standard regions, the winding heads have the first winding head shape; in the transition region, the winding heads of at least one wave winding wire or group of wave winding wires have the fifth winding head shape and the winding heads of at least one other wave winding wire or group of wave winding wires have the third wave winding shape; and at the end region, the winding heads of the at least one wave winding wire or group of wave winding wires have the fifth winding head shape;       

     and in the second individual mat, 
     in the start region, the winding heads of at least one wave winding wire or group of wave winding wires have the fifth winding head shape; in the standard region and in the end region, the winding heads have the second winding head shape; and in the transition region, the winding heads of the at least one wave winding wire or group of wave winding wires have the fifth winding head shape and the winding heads of at least one other wave winding wire or group of wave winding wires have the third wave winding shape. 
     It is preferred that the first and the second individual mats are stacked on one another and that 
     in the first individual mat,
         in the start region and in the standard regions, the winding heads have the first winding head shape; in the transition region, the winding heads of at least one wave winding wire or group of wave winding wires have the sixth winding head shape and the winding heads of at least one other wave winding wire or group of wave winding wires have the fourth wave winding shape; and at the end region, the winding heads of the at least one wave winding wire or group of wave winding wires have the sixth winding head shape;       

     in the second individual mat, 
     in the start region, the winding heads of at least one wave winding wire or group of wave winding wires have the sixth winding head shape; in the standard region and in the end region, the winding heads have the second winding head shape; and in the transition region, the winding heads of the at least one wave winding wire or group of wave winding wires have the sixth winding head shape and the winding heads of at least one other wave winding wire or group of wave winding wires have the fourth wave winding shape. 
     It is preferred that the first and the second individual mats are stacked on one another and that 
     in the first individual mat,
         in the start region and in the standard region, the winding heads have the second winding head shape; in the transition region, the winding heads of at least one wave winding wire or group of wave winding wires have the third winding head shape and the winding heads of at least one other wave winding wire or group of wave winding wires have the fifth wave winding shape; and at the end region, the winding heads of the at least one wave winding wire or group of wave winding wires have the third winding head shape; and       

     in the second individual mat, 
     in the start region, the winding heads of at least one wave winding wire or group of wave winding wires have the third winding head shape; in the second standard regions and in the end region, the winding heads have the first winding head shape; and in the transition region, the winding heads of the at least one wave winding wire or group of wave winding wires have the third winding head shape and the winding heads of at least one other wave winding wire or group of wave winding wires have the fifth wave winding shape. 
     It is preferred that both the first individual mat and the second individual mat are winding mats according to one of the designs described above for the winding mat according to the invention and that the first and second individual mats are plugged into each other and that 
     in the first individual mat, 
     in the start region, the winding heads of at least one wave winding wire or each wave winding wire of a group of wave winding wires have the sixth winding head shape; in the standard regions, the winding heads have the second winding head shape; in the transition region, the winding heads of the at least one wave winding wire or group of wave winding wires comprise a sequence of at least one third and at least two sixth winding head shapes and the winding heads of at least one other wave winding wire or group of wave winding wires comprise a sequence of at least one first and at least one fourth wave winding shape; and at the end region, the winding heads of the at least one wave winding wire or group of wave winding wires comprise a sequence of at least one third and at least one sixth winding head shape; and 
     in the second individual mat, 
     in the start region, the winding heads of at least one wave winding wire or group of wave winding wires have the sixth winding head shape and the winding heads of another wave winding wire or group of wave winding wires have the third winding head shape; in the standard region, the winding heads have the first winding head shape; and in the transition region, the winding heads of the at least one wave winding wire or group of wave winding wires comprise a sequence of at least one second and at least one sixth winding head shape and the winding heads of at least one other wave winding wire or group of wave winding wires comprise a sequence of at least one sixth, at least one fourth and at least one third winding head shape; and in the end region, the winding heads of the at least one wave winding wire or group of wave winding wires have the second winding head shape and the winding heads of the other wave winding wire or group of wave winding wires have the sixth winding head shape. 
     It is preferred that both the first individual mat and the second individual mat are winding mats according to one of the designs described above for the winding mat according to the invention and that the first and second individual mats are plugged into each other and that 
     in the first individual mat,
         in the start region, the winding heads of at least one wave winding wire or each wave winding wire of a group of wave winding wires have the third winding head shape, in the standard regions, the winding heads have the first winding head shape, in the transition region, the winding heads of the at least one wave winding wire or group of wave winding wires comprise a sequence of at least one sixth and at least two third winding head shapes and the winding heads of at least one other wave winding wire or group of wave winding wires comprise a sequence of at least one second and at least one fifth wave winding shape, and at the end region, the winding heads of the at least one wave winding wire or group of wave winding wires comprise a sequence of at least one sixth and at least one third winding head shape; and       

     in the second individual mat, 
     in the start region, the winding heads of at least one wave winding wire or group of wave winding wires have the third winding head shape and the winding heads of another wave winding wire or group of wave winding wires have the sixth winding head shape; in the standard regions, the winding heads have the second winding head shape; and in the transition region, the winding heads of the at least one wave winding wire or group of wave winding wires comprise a sequence of at least one first and at least one third winding head shape and the winding heads of at least one other wave winding wire or group of wave winding wires comprise a sequence of at least one third, at least one fifth and at least one sixth winding head shape; and in the end region, the winding heads of said one wave winding wire or group of wave winding wires have the first winding head shape and the winding heads of the other wave winding wire or group of wave winding wires have the third winding head shape. 
     It is preferred that the sub-sections of the individual mats plugged into each other are offset in height to each other. 
     There is also described a component of an electric machine, the component comprising a component body and a coil winding supported thereon, which is formed by a winding mat wound up in multiple layers which can be obtained using the winding mat manufacturing method according to a preferred embodiment of the invention, or a coil mat which can be obtained using the coil mat manufacturing method according to a preferred embodiment of the invention. 
     The component is preferably designed as a stator, the component body being an annular housing with radial slots in which the straight wire sections are accommodated. 
     According to one aspect, the invention relates to a winding mat manufacturing method for manufacturing a winding mat to form a coil winding of a component of an electric machine, the method comprising: 
     a) preparing several wave winding wires bent in a wave shape and extending in a longitudinal direction and having longitudinally spaced-apart straight wire sections extending in a transverse direction running transversely to the longitudinal direction, and intermediate roof-shaped winding heads such that adjacent straight wire sections are interconnected by a winding head bent in a roof shape to form a half-wave section in such a manner that first half-wave sections having first winding heads bent in a first direction and second half-wave sections having second winding heads bent in an opposite second direction are alternately provided and a first half-wave section and an adjacent second half-wave section respectively form a wave section, 
     b) joining the wave winding wires not by interlacing or twisting, but by plugging the wave winding wires into each other, comprising: 
     b1) arranging a first and a second wave winding wire side by side so that their straight wire sections are aligned with each other with a common directional component; 
     b2) arranging a first sub-section and an adjacent second sub-section of the first wave winding wire in such a way that the first sub-section is higher than the second sub-section, and arranging a first sub-section of the second wave winding wire opposite the first sub-section of the first wave winding wire in such a way that it can be pushed under the first sub-section of the first wave winding wire, and arranging a second sub-section of the second wave winding wire opposite the second section of the first wave winding wire in such a way that it can be pushed over the second sub-section of the first wave winding wire, and 
     b3) pushing the first wave winding wire and the second wave winding wire into each other in the direction of the directional component of the straight wire sections aligned with each other, the first sub-section of the second wave winding wire being pushed under the first sub-section of the first wave winding wire and the second sub-section of the second wave winding wire being pushed over the second sub-section of the first wave winding wire. 
     It is preferred that step a) includes: 
     a1) forming the winding heads by respectively creating a central roof bend and a transition bend in the transition region to the associated straight wire sections and a counter-bend between the transition bends and the roof bend. 
     It is preferred that step a) includes: 
     a2) preparing the wave winding wires having a wire thickness which, measured in a height direction running transversely to the longitudinal direction and transversely to the transverse direction at the straight wire sections, extends over a wire thickness dimension. 
     It is preferred that step a) includes: 
     a3) preparing wave winding wires having a rectangular cross-section. 
     It is preferred that step a) includes: 
     a4) preparing the first and second wave winding wires having winding heads adapted to form crossover points, wherein at least a section of at least one winding head of the first sub-section of the first wave winding wire which is designed to form a crossover point is higher than the straight wire sections connected by this winding head by a height extension corresponding to at least half a wire thickness, and a section of the winding head of the first sub-section of the second wave winding wire which is designed to form a crossover point is lower than the straight wire sections connected by this winding head by a height extension corresponding to at least half a wire thickness and/or wherein at least a section of at least one winding head of the second sub-section of the first wave winding wire which is designed to form a crossover point, is lower than the straight wire sections connected by this winding head by a height extension corresponding to a least half a wire thickness, and a section of the winding head of the second sub-section of the second wave winding wire which is designed to form a crossover point is higher than the straight wire sections connected by this winding head by a height extension corresponding to at least half a wire thickness. 
     It is preferred that step a) includes: 
     a5) performing step a2) and introducing height offsets into the winding heads by: 
     bending a first height offset by half a height extension dimension at a first winding head section which connects to a first straight wire section, 
     bending a second height offset by a full height extension dimension at a second winding head section which connects to the first winding head section, and 
     bending a third height offset by half a height extension dimension at a third winding head section which extends between the second winding head section and a second straight wire section. 
     Further preferably, the height extension dimension is chosen to be equal to the wire thickness dimension or more preferably equal to the wire thickness dimension plus a predetermined tolerance. 
     Preferably the height extension dimension is selected depending on the wire thickness. In particular, the height extension dimension is dependent on the wire thickness dimension. Preferably, the height extension dimension results from the wire thickness as well as a tolerance that takes into account a play/clearance to the wire below/next to it as well as other distances selected for design reasons. The height extension dimension indicates how high the jump in the winding heads is. The tolerance by which the height extension dimension is greater than the wire thickness dimension is preferably much smaller than the wire thickness dimension and is, for example, in a range of 0.001% to 5% of the wire thickness. Preferably, the typical tolerance values are taken into account in the tolerance dimension in such a way that adjacent wires lie on each other without tension and there is preferably a small clearance between adjacent wires lying on each other. 
     It is preferred that step a) includes: 
     a6) preparing 3n wave winding wires, n being a natural number greater than 0 
     It is preferred that step a5) includes bending the respective height offset in a first height direction which when the winding mat is used as intended corresponds to a direction radially outwards with respect to a central axis of the component, or in an opposite second height direction which when the winding mat is used as intended corresponds to a direction radially inwards with respect to a central axis of the component. 
     It is preferred that step a5) further includes: 
     a5a) introducing the first height offset into the region of a transition bend and the third height offset into the region of the other transition bend and the second height offset into the region of the roof bend. 
     It is preferred that step a5) further includes: 
     a5b) forming the height offsets to form a winding head shape selected from a group of winding head shapes comprising: 
     a first winding head shape where the first height offset is directed in the second height direction, the second height offset is directed in the first height direction and the third height offset is directed in the second height direction, 
     a second winding head shape where the first height offset is directed in the first height direction, the second height offset is directed in the second height direction and the third height offset is directed in the first height direction, 
     a third winding head shape where the first height offset is directed in the first height direction, the second height offset is directed in the first height direction and the third height offset is directed in the second height direction, 
     a fourth winding head shape where the first height offset is directed in the first height direction, the second height offset is directed in the second height direction and the third height offset is directed in the second height direction, 
     a fifth winding head shape where the first height offset is directed in the second height direction, the second height offset is directed in the first height direction and the third height offset is directed in the first height direction, and 
     a sixth winding head shape where the first height offset is directed in the second height direction, the second height offset is directed in the second height direction and the third height offset is directed in the first height direction. 
     It is preferred that step a5) further includes: 
     a5c) selecting at least one standard region situated between a start region and an end region of the winding mat and shaping each winding head in the standard region in such a way that the first height offset and the third height offset are directed in the same height direction and the second height offset is directed in the opposite height direction. 
     It is preferred that step a5) further includes: 
     a5d) selecting a transition region where the winding mat is to receive a step in the height direction to form a stair-like stepping of the winding mat, and 
     forming winding heads in wave winding wires at the transition region in such a way that in at least one winding head at the first wave winding wire the first height offset is directed in the first height direction, the second height offset is directed in the first direction, and the third height offset is directed in the second direction, and in at least one winding head at the second wave winding wire the first height offset is directed in the second height direction, the second height offset is directed in the second height direction, and the third height offset is directed in the first height direction. 
     It is preferred that step a5) further includes: 
     a5e) shaping at least one winding head at at least one of the first or second wave winding wires at a start region or an end region of the winding mat in such a way that the first height offset is directed in the first height direction, the second height offset is directed in the second height direction, and the third height offset is directed in the first height direction or the first height offset is directed in the second height direction, the second height offset is directed in the first height direction, and the third height offset is directed in the first height direction. 
     It is preferred that at least some, several or all of the sub-sections in step b) are half-wave sections or wave sections or are each formed by a plurality of half-wave sections or wave sections. 
     It is preferred that the wave mat is produced stepped in a stair-like manner, with at least one transition region forming a step in the height direction, wherein in step b), the sub-sections of the first and the second wave winding wires are plugged into each other in the transition region. 
     It is preferred that in step b) the sub-sections of the first and the second wave winding wires are plugged into each other in a start region and/or an end region of the wave mat. 
     It is preferred that the first and the second wave winding wire with their first and second sub-sections are plugged into each other at a start region of the winding mat and/or at an end region of the winding mat and are stacked on top of each other in at least one region in between without plugging sub-sections into each other. 
     It is preferred that in step b) a pair or a group of first wave winding wires are respectively plugged into a pair or a group of second wave winding wires. 
     It is preferred that in step a) at least one first, at least one second and at least one third wave winding wire are prepared and that in step b) only the at least one first and the at least one second wave winding wire are plugged, and that said at least one third wave winding wire is joined with the at least one first and the at least one second wave winding wire by stacking and not by plugging. 
     It is preferred that step a) comprises one or both of steps a4) or a5), and step b) further comprises: 
     b7) plugging the first wave winding wire and the second wave winding wire into each other in an alignment position where the longitudinal center axes of the first and second wave winding wires lie on top of each other, wherein the straight wire sections of the first and second wave winding wires become arranged on a common plane, at least in a standard region of the wave mat. 
     It is preferred that step b) is repeated with the unit already formed of several wave winding wires plugged into each other and with a further wave winding wire or pair or group of further wave winding wires in a manner analogous to that of the first wave winding wire and the second wave winding wire until all wave winding wires are joined together in a winding mat. 
     It is preferred that the winding mat manufacturing method is carried out to produce a single-layer winding mat in which a sequence of individual straight wire sections not superimposed on each other is provided in the longitudinal direction of the winding mat. 
     It is preferred that in step b) the first and/or the second sub-section of both the first and the second wave winding wires each comprise at least three winding heads so that at least one central winding head is situated between at least two outer winding heads, and that step b) further comprises the steps to be carried out after step b3): 
     b4) pushing the first and the second wave winding wires into each other beyond the alignment position where the first and the second wave winding wires are aligned with their longitudinal central axes relative to one another until the winding heads which in step b1) were located on the side facing away from the other wave winding wire abut against one another; 
     b5) swapping the height position of the at least one central winding head of the first wave winding wire and the second wave winding wire and 
     b6) pushing the first and the second wave winding wires into each other into the alignment position. 
     According to another aspect, the invention provides a coil mat manufacturing method for manufacturing a coil mat to form the coil winding of a component of an electrical machine, the method comprising: 
     i) producing a first individual mat by joining 3n1 individual wave winding wires, 
     j) producing a second individual mat by joining 3n2 individual wave winding wires; and 
     k) joining the first individual mat and the second individual mat, wherein n1 and n2 are natural numbers greater than 0 and wherein the wave winding wires have straight wire sections spaced apart in the longitudinal direction of the coil mat and extending in a transverse direction running transversely to the longitudinal direction, and intermediate roof-shaped winding heads such that adjacent straight wire sections are connected to each other by a winding head bent in a roof shape, thus forming half-wave sections in such a manner that first half-wave sections with first winding heads bent in a first direction and second half-wave sections with second winding heads bent in an opposite direction are alternately provided, and a first half-wave section and an adjacent second half-wave section respectively form a wave section. 
     In a first alternative of the coil mat manufacturing method, at least one or both of steps i) and j) comprise carrying out the wave mat manufacturing method according to the configuration described above. 
     In a second alternative of the coil mat manufacturing method, which may be provided alone or in combination with the first alternative, step k) comprises: 
     joining the individual mats not by interlacing or twisting, but by plugging the individual mats together, comprising: 
     k1) arranging the first and the second individual mats side by side so that their straight wire sections are aligned with each another with a common directional component; 
     k2) arranging a first sub-section and an adjacent second sub-section of the first individual mat in such a way that the first sub-section is higher than the second sub-section, and arranging a first sub-section of the second individual mat opposite the first sub-section of the first individual mat in such a way that it can be pushed under the first sub-section of the first individual mat, and a second sub-section of the second individual mat opposite the second sub-section of the first individual mat in such a way that it can be pushed over the second sub-section of the first individual mat, and 
     k3) pushing the first individual mat and the second individual mat into each other in the direction of the directional component of the straight wire sections aligned with each other, the first sub-section of the second individual mat being pushed under the first sub-section of the first individual mat and the second sub-section of the second individual mat being pushed over the second sub-section of the first individual mat. 
     It is preferred that step k) is performed in such a way that a respective straight wire section of the first individual mat and a respective straight wire section of the second individual mat come to lie on each other in the height direction. 
     It is preferred that steps i) and j) be carried out in such a way that the straight wire sections of the first sub-section of the first individual mat are higher than the straight wire sections of the second sub-section of the first individual mat and/or of the first sub-section of the second individual mat by a height extension corresponding at least to the wire thickness. 
     It is preferred that steps i) and j) be carried out in such a way that the straight wire sections of the second sub-section of the second individual mat are higher than the straight wire sections of the first sub-section of the second individual mat and/or of the second sub-section of the first individual mat by a height extension dimension corresponding to at least the wire thickness. 
     It is preferred that step k) comprises: 
     k7) plugging the first individual mat and the second individual mat into each other in an aligned position where the longitudinal central axes of the first and the second individual mats lie one on top of the other. 
     It is preferred that in step k) the first and/or the second sub-sections of both the first and the second wave winding wires each comprise at least three winding head groups such that at least one central winding head group is respectively situated between at least two outer winding head groups, and that step k) further comprises the steps to be carried out after step k3): 
     k4) pushing the first and second individual mats into each other beyond the alignment position where the first and second individual mats are aligned with their longitudinal central axes relative to one another until the winding heads which in step k1) were located on the side facing away from the respective other individual mat abut against each other; 
     k5) swapping the height position of the central winding head groups of the first individual mat and the second individual mat; and 
     k6) pushing the first and the second individual mats into each other in the alignment position. 
     It is preferred that steps i) and j) be carried out in such a way that 
     each winding head is provided with a first height offset by half a height extension dimension at a first winding head section which connects to a first straight wire section, a second height offset by a full height extension dimension at a second winding head section which connects to the first winding head section, and a third height offset by half a height extension dimension at a third winding head section which extends between the second winding head section and the second straight wire section. 
     Further preferably, it is provided that each wave winding wire has a wire thickness in the straight sections which, measured in a height direction running transversely to the longitudinal direction and transversely to the transverse direction, extends over a wire thickness dimension, and that the height extension dimension is selected depending on the wire thickness dimension. Preferably, the height extension dimension is determined to be equal to the wire thickness or equal to the wire thickness plus a predetermined tolerance. 
     Preferably, the height extension dimension is dependent on the wire thickness. In particular, the height extension dimension is dependent on the wire thickness dimension. Preferably, the height extension dimension results from the wire thickness plus a tolerance that takes into account room/clearance to the wire below/next to it as well as other distances chosen for design reasons. The height extension dimension indicates how high the jump in the winding heads is. The tolerance by which the height extension dimension is greater than the wire thickness dimension is preferably much smaller than the wire thickness dimension and is, for example, in a range of 0.001% to 5% of the wire thickness. Preferably, typical tolerance values are taken into account in the tolerance dimension in such a way that adjacent wires lie on each other without tension and there is preferably a small clearance between adjacent wires lying on each other. 
     It is preferred that the individual mats are stepped in a stair-like manner, with at least one transition region forming a step in the height direction in such a way that the individual mats and thus also the resulting coil mat have a start region, several standard regions with a respective intermediate transition region, and an end region, 
     wherein, when the coil mat is used as intended, the first height direction in the height offsets of the winding heads corresponds to a direction radially outwards and the second height direction corresponds to a direction radially inwards, 
     that the individual winding heads are designed with a winding head shape which is selected from a group of winding head shapes comprising: 
     a first winding head shape where the first height offset is directed in the second height direction, the second height offset is directed in the first height direction and the third height offset is directed in the second height direction, 
     a second winding head shape where the first height offset is directed in the first height direction, the second height offset is directed in the second height direction and the third height offset is directed in the first height direction, 
     a third winding head shape where the first height offset is directed in the first height direction, the second height offset is directed in the first height direction and the third height offset is directed in the second height direction, 
     a fourth winding head shape where the first height offset is directed in the first height direction, the second height offset is directed in the second height direction and the third height offset is directed in the second height direction, 
     a fifth winding head shape where the first height offset is directed in the second height direction, the second height offset is directed in the first height direction and the third height offset is directed in the first height direction; and 
     a sixth winding head shape where the first height offset is directed in the second height direction, the second height offset is directed in the second height direction and the third height offset is directed in the first height direction, 
     and that in said standard regions winding heads with the first or the second winding head shape are provided and that at least some of the wave winding wires in the transition region are given winding heads with the third and/or the fourth and/or the fifth and/or the sixth winding head shape. 
     It is preferred that the first and the second individual mats are stacked on one another and that 
     in the first individual mat,
         in the start region and in the standard regions, the winding heads are given the second winding head shape; in the transition region, the winding heads of at least one wave winding wire or group of wave winding wires are given the fourth winding head shape and the winding heads of at least one other wave winding wire or group of wave winding wires are given the sixth wave winding shape; and at the end region, the winding heads of the at least one wave winding wire or group of wave winding wires are given the fourth winding head shape; and       

     in the second individual mat, 
     in the start region, the winding heads of at least one wave winding wire or group of wave winding wires are given the fourth winding head shape; in the standard regions as well as in the end region, the winding heads are given the first winding head shape: and in the transition region, the winding heads of the at least one wave winding wire or group of wave winding wires are given the fourth winding head shape and the winding heads of at least one other wave winding wire or group of wave winding wires are given the sixth wave winding shape. 
     It is preferred that the first and the second individual mats are stacked on one another and that 
     in the first individual mat,
         in the start region and in the standard regions, the winding heads are given the first winding head shape; in the transition region, the winding heads of at least one wave winding wire or group of wave winding wires are given the fifth winding head shape and the winding heads of at least one other wave winding wire or group of wave winding wires are given the third wave winding shape; and at the end region, the winding heads of the at least one wave winding wire or group of wave winding wires are given the fifth winding head shape; and       

     in the second individual mat, 
     in the start region, the winding heads of at least one wave winding wire or group of wave winding wires are given the fifth winding head shape; in the standard regions as well as in the end region, the winding heads are given the second winding head shape; and in the transition region, the winding heads of the at least one wave winding wire or group of wave winding wires are given the fifth winding head shape and the winding heads of at least one other wave winding wire or group of wave winding wires are given the third wave winding shape. 
     It is preferred that the first and the second individual mats are stacked on one another and that 
     in the first individual mat,
         in the start region and in the standard regions, the winding heads are given the first winding head shape; in the transition region, the winding heads of at least one wave winding wire or group of wave winding wires are given the sixth winding head shape and the winding heads of at least one other wave winding wire or group of wave winding wires are given the fourth wave winding shape; and at the end region, the winding heads of the at least one wave winding wire or group of wave winding wires are given the sixth winding head shape; and       

     in the second individual mat, 
     in the start region, the winding heads of at least one wave winding wire or group of wave winding wires are given the sixth winding head shape; in the standard regions as well as in the end region, the winding heads are given the second winding head shape; and in the transition region, the winding heads of the at least one wave winding wire or group of wave winding wires are given the sixth winding head shape and the winding heads of at least one other wave winding wire or group of wave winding wires are given the fourth wave winding shape. 
     It is preferred that the first and the second individual mats are stacked on one another and that 
     in the first individual mat,
         in the start region and in the standard regions, the winding heads are given the second winding head shape; in the transition region, the winding heads of at least one wave winding wire or group of wave winding wires are given the third winding head shape and the winding heads of at least one other wave winding wire or group of wave winding wires are given the fifth wave winding shape; and at the end region, the winding heads of the at least one wave winding wire or group of wave winding wires are given the third winding head shape; and       

     in the second individual mat, 
     in the start region, the winding heads of at least one wave winding wire or group of wave winding wires are given the third winding head shape; in the second standard regions as well as in the end region, the winding heads are given the first winding head shape; and in the transition region, the winding heads of the at least one wave winding wire or group of wave winding wires are given the third winding head shape and the winding heads of at least one other wave winding wire or group of wave winding wires are given the fifth wave winding shape. 
     It is preferred that both the first individual mat and the second individual mat are manufactured by a winding mat manufacturing method according to one of the configurations described above and that the first and second individual mats are plugged into each other and that 
     in the first individual mat, 
     in the start region, the winding heads of at least one wave winding wire or each wave winding wire of a group of wave winding wires are given the sixth winding head shape; in the standard regions, the winding heads are given the second winding head shape; in the transition region, the winding heads of the at least one wave winding wire or group of wave winding wires are given a sequence of at least one third and at least two sixth winding head shapes and the winding heads of at least one other wave winding wire or group of wave winding wires are given a sequence of at least one first and at least one fourth wave winding shape; and at the end region, the winding heads of the at least one wave winding wire or group of wave winding wires are given a sequence of at least one third and at least one sixth winding head shape; and 
     in the second individual mat, 
     in the start region, the winding heads of at least one wave winding wire or group of wave winding wires are given the sixth winding head shape and the winding heads of another wave winding wire or group of wave winding wires are given the third winding head shape; in the standard regions, the winding heads are given the first winding head shape; and in the transition region, the winding heads of the at least one wave winding wire or group of wave winding wires are given a sequence of at least one second and at least one sixth winding head shape and the winding heads of at least one other wave winding wire or group of wave winding wires are given a sequence of at least one sixth, at least one fourth and at least one third winding head shape; and in the end region, the winding heads of said one wave winding wire or group of wave winding wires are given the second winding head shape and the winding heads of the other wave winding wire or group of wave winding wires are given the sixth winding head shape. 
     It is preferred that both the first individual mat and the second individual mat are manufactured by a winding mat manufacturing method according to one of the configurations described above and that the first and second individual mats are plugged into each other and that 
     in the first individual mat,
         in the start region, the winding heads of at least one wave winding wire or each wave winding wire of a group of wave winding wires are given the third winding head shape; in the standard regions, the winding heads are given the first winding head shape; in the transition region, the winding heads of the at least one wave winding wire or group of wave winding wires are given a sequence of at least one sixth and at least two third winding head shapes and the winding heads of at least one other wave winding wire or group of wave winding wires are given a sequence of at least one second and at least one fifth wave winding shape; and at the end region, the winding heads of the at least one wave winding wire or group of wave winding wires are given a sequence of at least one sixth and at least one third winding head shape; and       

     in the second individual mat, 
     in the start region, the winding heads of at least one wave winding wire or group of wave winding wires are given the third winding head shape and the winding heads of another wave winding wire or group of wave winding wires are given the sixth winding head shape; in the standard regions, the winding heads are given the second winding head shape; and in the transition region, the winding heads of the at least one wave winding wire or group of wave winding wires are given a sequence of at least one first and at least one third winding head shape and the winding heads of at least one other wave winding wire or group of wave winding wires are given a sequence of at least one third, at least one fifth and at least one sixth winding head shape; and in the end region, the winding heads of said one wave winding wire or group of wave winding wires are given the first winding head shape and the winding heads of the other wave winding wire or group of wave winding wires are given the third winding head shape. 
     A preferred embodiment of the coil mat manufacturing method is characterized by the method being carried out in such a way that a coil mat without conductor swap and without layer swap is produced. 
     A preferred embodiment of the coil mat manufacturing method is characterized by the method being carried out in such a way that a coil mat with conductor swap and without layer swap is produced. 
     A preferred embodiment of the coil mat manufacturing method is characterized by the method being carried out in such a way that a coil mat without conductor swap and with layer swap is produced. 
     A preferred embodiment of the coil mat manufacturing method is characterized by the method being carried out in such a way that a coil mat with conductor swap and with layer swap is produced. 
     Advantageously, the component of an electric machine is manufactured by the following steps: 
     preparing a component body, carrying out a method according to one of the configurations described above and winding up the mat thus produced to obtain said one coil winding of the component of the electric machine, and inserting the wound-up mat into the component body. 
     According to a further aspect, the invention provides a device for carrying out a method according to any of the above configurations, comprising: 
     a supply device for supplying wave winding wires or individual mats, and 
     a plugging device for plugging the wave winding wires or the individual mats together by moving the same towards each other in a direction running transversely to their longitudinal direction. 
     It is preferred that the supply device comprises a wave winding wire manufacturing device for bending the wave sections from a wire, and/or a wave head shaping device for shaping the wave heads. 
     It is preferred that the wave head shaping device has several bending jaws having bending radii for creating the height offsets. 
     It is preferred that the device has a control system arranged to control the device to perform the steps of the method according to one of the above configurations. 
     According to a further aspect, the invention provides a computer program product or a computer program including machine readable control instructions which when loaded into a computer of the control system cause the device to perform the steps of the method according to any of the foregoing configurations. 
     Preferably, the wave winding wires are produced by a method and/or device and hence supplied by the supply device as described and shown in the German patent application 10 2017 127 634.3. 
     Particular embodiments of the invention concern a pluggable wave winding mat. Methods and devices for manufacturing such a mat are also described. 
     Preferably, the wave winding wires are formed from a profile wire having a profile shape deviating from a round cross-section, in particular, a rectangular profile. A rectangular profile shape has advantages because the volume of the slot is optimally filled with a conductor cross-section. The mats and the processes described here are particularly suitable for such profile wires, since the profile wires are not twisted and therefore the stress on the wires and their insulation is low. This leads to an increased reliability and reduces the risk of wire damage. 
     In the component, conductors of various individual mats of a coil winding or a coil mat are preferably located in one slot. 
     In order to achieve the highest possible (optimum) efficiency in an electric machine, the coil winding has to meet various properties. A problem that exists in prior art is that if such criteria are met (e.g., optimum filling with conductor material, optimized conductor paths), the coil mat must either be interlaced or the production of the individual wires is very costly. With the designs according to the invention, however, it is possible to produce a winding mat and/or coil mat which consists of individual wires which are as similar as possible and do not have to be interlaced. 
     For preparing the wave winding wires, a wire manufacturing device is advantageously provided, which makes it possible to offset a winding head with three bend points. It is also advantageous to be able to vary both the Z-direction (up or down) and the bending height in the Z-direction of all bend points in each winding head. It is also advantageous to be able to produce wires for different core stack lengths and shift dimensions. The shift dimension describes the average distance that a wire in the coil head bridges in the X-direction. The shift dimension can also vary within a wire. 
     Preferably, a device for offsetting wave winding heads at a wave winding wire is provided for this purpose. 
     Further preferably, in order to produce a winding mat from the individual wave winding wires, a wire handling is proposed which makes it possible to transport, stack and plug-fit the wires. In prior art, the wires have to be interwoven or interlaced in a winding mat in order to produce certain winding schemes; in this case, wire handling is very complex or partly not feasible because the wires have to be twisted. This process step can be replaced by cross-plugging, which can be achieved by pure linear movements. Cross-plugging can always be used if a layer swap on both sides of the core stack is to be achieved. 
     Preferred embodiments of the invention make it possible to manufacture a winding mat that can be produced by well automatable processes and fulfils the necessary requirements. In addition, the winding head can be designed in such a way that the entire winding head has a lowest possible radial height. Different embodiments provide various winding mats or coil mats, which differ in their electrical properties and manufacturing processes. The better the electrical properties, the higher the manufacturing costs. But even the costs for automating the manufacturing process are still considerably lower than with known methods, even with best electrical properties. 
     Since interlacing or interweaving proposed in prior art is a very costly process and is also very difficult to automate, the winding mat according to advantageous configurations of the invention is achieved in such a way that it can be produced by stacking, plugging and/or cross-plugging, with partially the same electrical advantages. Special characteristics are found in the method and in the resulting head geometry of the individual wires. 
     The individual mats are preferably connected in series for potential equalization. In configurations of the invention, a continuous swap of layers does not take place, thus no interlacing of the winding mat is required. 
     Preferred designs of the invention have three jumps in the individual winding heads. Preferably, there are also winding heads on two planes, but both planes are offset to the plane of the straight sections. Thus, the winding mat and also the coil mat formed from it have a very small extension in the height direction (which corresponds to the radial direction when the winding mat/coil mat is wound up in the component) in the region of the winding heads. 
     Preferably, the radial extension of a coil mat or winding mat wound in n layers in the component has a maximum value of (n+1) times the height extension dimension in the region of the winding heads. 
     Advantageously, the wire always remains flat and is not twisted. This is particularly advantageous for profile wire. 
     Preferably, a plugged mat and defined head shapes are proposed. 
     Preferably, a plugged mat and an interconnection for potential equalization are proposed. 
     Preferably, three jumps are provided in the head and the respective winding head can also be on two planes, but both planes are offset to the plane of the straight sections. Preferably a coil step of 5-7 in two planes (if with layer swap) is proposed. Preferably, a winding having 12 conductors and a coil step of 6 in the wiring area is proposed. Preferably, a series connection of the individual mats for equipotential bonding is provided. Advantageously, a layer swap and a coil step of 5-7 can be provided and, in addition, the winding mat is not interlaced. 
     Plugging instead of interlacing has the advantage of easier automatic production. With a suitable head shape, the individual wires jump to the correct position when plugged and align themselves with their straight sections on one plane (except at the stair jump, if provided). The individual wires can also be easily taken apart again, should this ever be necessary. Plugging can be done without any load on the wires, especially without twisting. 
     A further aspect of the invention relates to offsetting in a flat winding. In particular, offsetting in winding heads of wave winding wires designed as flat winding is described. 
     Preferably, the winding heads are bent at a first to third point, and in the region of each of these bends an offset is also introduced to obtain a jump in height. A more wire-friendly process is created due to three jump points. 
     The wire manufacturing device preferably includes a device for bending height offsets. 
     The device for bending height offsets is preferably designed in such a way that all flat wire sections of the individual wires can be clamped individually and moved individually in the Z-direction. In this manner, all height offsets are bent simultaneously. The jump height is variably adjustable. 
     In order to produce the different winding head shapes proposed here, three clamping operations are preferably provided simultaneously on three clamping surfaces per winding head. In addition, the clamping force or also a specific clearance can be set. 
     The device for bending height offsets is preferably designed in such a way that a single wire can be bent or several parallel single wires can be bent at a time. 
     In order to exclude a change in cross-section, the wire is preferably free in space at the bending points between the clamping surfaces. In this way, the theoretical elongation of the neutral fiber due to a change in radius at the position of the height offset can be prevented. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Embodiments of the invention will be described in more detail in the following with reference to the attached drawings in which it is shown by: 
         FIG. 1  is a perspective view of two parallel wave winding wires for the production of a winding mat; 
         FIG. 2  is a cross-section through a component of an electrical machine, in particular a stator, preferably of an electric motor, with a coil winding inserted into slots of a housing, which coil winding is formed from a coil mat formed from several winding mats; 
         FIG. 3  is a schematic representation of a first variant of a coil mat or winding mat designed as a flat mat; 
         FIG. 4  is a schematic representation, similar to  FIG. 3 , of a second variant of a coil mat or winding mat designed as a stair-like mat; 
         FIG. 5  is a plan view of a coil mat, seen in Z-direction (height direction) corresponding to the radial direction in the component according to  FIG. 2 ; 
         FIG. 6  is a plan view of a winding head of the two wave winding wires of  FIG. 1 ; 
         FIG. 7  is a perspective view of one winding head of the two wave winding wires of  FIG. 1 ; 
         FIG. 8  is a plan view of clamping surfaces of a bending device for bending the winding head shape as shown in  FIGS. 6 and 7 ; 
         FIG. 9  is a view of the bending device seen in an X-direction of the wave winding wires (longitudinal direction) corresponding to the circumferential direction in the component; 
         FIG. 10  is a perspective view of the bending device; 
         FIG. 11  is an overall perspective view of a wave winding wire supply device comprising the bending device; 
         FIG. 12  is a plan view in a Z-direction of the wave winding wires corresponding to the later radial direction in the component, looking at clamping and bending units of the bending device; 
         FIG. 13  is a perspective view of a bending jaw of one of the clamping units; 
         FIG. 14  is a flow chart of a bending process for bending the winding heads; i.e. for introducing height offsets into the winding heads; 
         FIGS. 15 a  to 15 f    are sectional views through a half-wave shape of one of the wave winding wires as viewed in a y-direction (transverse direction) corresponding to the later axial direction in the component, showing corresponding height offsets in the Z-direction of a first to sixth winding head shape; 
         FIGS. 16 to 18  are plan views of a first and a second wave winding wire at different stages of plugging the wave winding wires in the course of manufacturing a winding mat; 
         FIGS. 19 and 20  are plan views of an arrangement of wave winding wires at different stages of plugging for forming the winding mat; 
         FIG. 21  is a perspective view of an arrangement of wave winding wires to illustrate pairwise plugging; 
         FIG. 22  is a first and a second winding mat as individual mats plugged together to form a coil mat, in a first stage of a coil mat manufacturing process; 
         FIGS. 23 to 24  are perspective views of the first and second winding mats during different stages of the coil mat manufacturing process; 
         FIGS. 25 a  to 25 d    are plan views of two pairs of wave winding wires during different stages of a variant of the plugging process for producing a coil mat-cross-plugging; 
         FIG. 26  is a schematic representation of a first embodiment of a coil mat with wire routes, as well as a first individual mat and a second individual mat of this coil mat with the winding head shapes provided in the individual mats; 
         FIG. 27  is a schematic representation of a second type of a coil mat with wire routes, as well as a first individual mat and a second individual mat of this coil mat with the winding head shapes provided in the individual mats; 
         FIG. 28  is a schematic representation of a third type of coil mat with wire routes, as well as a first individual mat and a second individual mat of this coil mat with the winding head shapes provided in the individual mats; 
         FIG. 29  is a representation of an end region of a wave winding wire of the coil mat with indicated variants of wire outlets; 
         FIG. 30  is a first perspective view of a connected coil winding formed from a coil mat with a uniform coil step; 
         FIG. 31  is a perspective view, similar to  FIG. 30 , of a connected coil winding formed from a coil mat with an alternating coil step; 
         FIG. 32  is a second perspective view of the interconnected coil winding formed from a coil mat with a uniform coil step; 
         FIG. 33  is a second perspective view, similar to  FIG. 32 , of the interconnected coil winding formed from the coil mat with an alternating coil step; 
         FIG. 34  is a simplified representation of a segment of an explanatory component of an electrical machine, e.g., a stator, comprising a housing provided with slots, with a coil winding which is inserted into the slots and designed as a single-layer winding; and 
         FIG. 35  is a representation, similar to  FIG. 34 , of the housing of the explanatory component, with the coil winding shown as a two-layer winding with a jump in the winding heads. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       FIG. 1  shows a sub-section of a pair of wave winding wires  24 ,  24   a ,  24   b  in a perspective view, which wave winding wires can be combined into a winding mat for creating a coil winding  20 .  FIG. 1  shows, in particular, a wave section  26  of the pair of wave winding wires  24 ,  24   a ,  24   b . Each wave winding wire  24  extends in its longitudinal direction pointing in the X-direction in  FIG. 1  and comprises a series of straight wire sections  28  spaced apart in this longitudinal direction and extending in a transverse direction—Y-direction, with adjacent straight wire sections  28  being connected to each other by a winding head  30 . 
     The straight wire sections  28  are used to be inserted into the slots  16  of a component  12 , e.g., a stator  14 . The length of the straight wire section  28  thus essentially corresponds to the axial construction length of the housing  10  which, for example, is formed from a core stack. 
     Accordingly, in the later intended use of a coil winding  20  formed from the wave winding wires  24 , the Y-direction—transverse direction—corresponds to the axial direction in the component  12 ; the longitudinal direction—X-direction—corresponds to the circumferential direction in the component  12 , and the Z-direction, referred to here as the height direction, corresponds to the radial direction when the coil winding  20  formed from the wave winding wires  24  is used as intended. 
     The wave winding wires  24  are designed as a flat winding and are wave-shaped, with a first winding head  30   a  bent in a first bending direction and a second winding head  30   d  having an opposite second bending direction being alternately provided in the longitudinal direction of the wave winding wire  24 . Thus, the first winding head  30   a  is provided at one end of a straight wire section  28  and the second winding head  30   b  at the second end of the straight wire section. A straight wire section  28  and a first winding head  30   a  form a first half-wave section  32   a  and another straight wire section  28  and a second winding head  30   a  form a second half-wave section  32   b , and a wave section  26  is formed of a first half-wave section  32   a  and a second half-wave section  32   b . The distance between adjacent straight wire sections  28  of a wave winding wire  24 , which are respectively connected to each another by a winding head  30 , corresponds to the shift dimension. 
     Each winding head  30  is respectively bent at a first bend point  34   a , a second bend point  34   b  and a third bend point  34   c , the bend points  34   a ,  34   b  and  34   c  being spaced apart from one another and connected to one another by connecting sections  36 . These connecting sections  36  are essentially straight, except for a counter-bend which is explained in more detail below. 
     At the bend points  34   a ,  34   b ,  34   c , the wave winding wire  24  is bent in the Y-X plane. Furthermore, this winding head  30  has a jump  22  in the height direction at each of the first to third bend points  34   a ,  34   b ,  34   c . Depending on the orientation of the jumps  22  at the bend points  34   a  to  34   c , different winding head shapes  1  to  6  are produced as a result, which will be discussed in more detail below. 
     Each winding head  30  is bent (cranked) at a total of the three bend points  34   a ,  34   b ,  34   c , whereby both the Z-direction—up or down—and the bending height of all bend points  34   a - 34   b  in the Z-direction can vary in each winding head  30 . 
     The jump  22  in the first bend point  34   a  forms a first height offset  38   a ; the jump  22  in the second bend point  34   b  forms a second height offset  38   b ; and the jump  22  in the third bend point  34   c  forms a third height offset  38   c.    
     The length of the straight wire sections  28  substantially corresponds to the length of the laminated core in the axial direction of the housing  10  formed as a core stack. Accordingly, the length of the straight wire sections  28  is chosen in accordance with the axial construction length of the housing  10 ; altogether, the wave winding wires  24  are produced in each case corresponding to the housing  10 , with straight wire sections  28  adapted thereto and with a shift dimension adapted thereto. A supply device for supplying the wave winding wires  24 , which will be explained later, is designed in such a way that the wave winding wires  24  can be manufactured with shift dimensions adapted to different core stack lengths and shift dimensions. The shift dimension describes the average distance a winding wire  24  bridges in the X-direction—longitudinal direction—in the winding head  30 . The shift dimension can also vary within a wave winding wire  24 . 
     From such winding wires  24 , as shown in  FIG. 1 , winding mats  40  are produced from which the coil winding  20  of a component  12 , in particular a stator  14 , can be formed, as shown in  FIG. 2 . 
       FIG. 2  shows, for example, a housing  10 , which is formed from a core stack, of a component  12  designed in particular as the stator  14  of an electric motor, the coil winding  20  formed from one or more winding mats  40  being inserted into radially inwardly open slots  16  in the housing  10  by winding up the winding mat  40 . The straight wire sections  28  are inserted into the slots  16 , with the first winding heads  30   a  protruding on one axial side of the housing  10  and the second winding heads  30   b  protruding on the other axial side of the housing  10 . 
     If a single-layer coil winding  20  is to be formed, this can be achieved with a single winding mat  40 . For forming a two-layer coil winding, a coil mat  42  composed of a first winding mat  40  and a second winding mat  40  as individual mats  44   a ,  44   b  can be used. A coil mat  40  consists of several individual wave winding wires  24 . These are combined into a first individual mat  44   a  and a second individual mat  44   b , each of which is designed as one layer. The individual mats  44   a ,  44   b  can then be joined together to form the coil mat  42  in such a way that a straight wire section  28  of the first individual mat  44   a  and a straight wire section of the second individual mat  44   b  always lie on one another. Exceptions are a start region  46  and an end region  48  of the coil mat  42 . 
     As shown in  FIG. 3 , the respective winding mat  40  and the coil mat  42  formed from it can be designed as a flat mat  50 . In the case of a flat mat  50 , all straight wire sections  28  in each winding mat  40  are on a common plane when not yet wound together, i.e., there is no height offset in the Z-direction between straight wire sections  28  within a winding mat  40 . If such a flat mat  50  is wound up several times to insert it into the component  12 , a tension is produced in a transition region  52  within the wave winding wires  24 , since the straight wire sections  28  change their radial position in this transition region  52 . 
     In order to avoid these tensions, it is also possible to provide a stair-shaped mat  54 , as shown in  FIG. 3 , where a height offset between straight wire sections  28  is provided in those areas of the stair-shaped mat  54  which come to lie in the transition region  52 . Thus, in a stair-shaped mat  54 , there is a step in the transition regions  52 , whereas in the standard regions  56 , which lie between the start region  46  and the transition region  52  or between two transition regions  52  or between the transition region  52  and the end region  48 , the straight wire sections  28  in each winding mat  40  are all in the same plane when not yet wound up, which means that there is no height offset between the straight wire sections  28  in the standard regions  56 . 
       FIG. 5  shows a plan view (in Z-direction) of one embodiment of a coil mat  42  which is composed of a first individual mat  44   a  designed as a winding mat  40  and a second individual mat  44   b  designed as a winding mat  40 . The first individual mat  44   a  is made of three n1 individual wave winding wires  24 , and the second individual mat  44   b  is made of three n2 wave winding wires  24 , n1 and n2 being natural numbers≥0. In the following examples, n1=n2=2. Accordingly, the first individual mat  44   y  comprises six wave winding wires  24  for example, which are designated aa, ab, ac, ad, ae and of in the following tables. Accordingly, the second individual mat  44   b  also comprises six wave winding wires  24 , which are designated by, bb, bc, bd, be and bf in the following tables. 
     Each winding mat  40  can be produced by stacking STP the wave winding wires  24  (simply putting them on top of each other) or, in particular, by plugging STK the individual wave winding wires  24 , which is explained in more detail below. The coil mat  42  can be produced by stacking STP the individual mats  44   a ,  44   b  or by plugging STK the individual mats  44   a ,  44   b , which is explained in more detail below. 
     By using these methods, which are explained in more detail below, different winding schemes can be created for the coil mat  42 , which are shown in the following tables 1 to 4. The respective winding scheme can be understood if the coil mat  42  is cut in the middle, as shown in  FIG. 5 , and then viewed in the X-direction from one side. 
     In the examples of winding schemes shown in tables 1 to 4, the first individual mat  44   a  has six wave winding wires  24   a - 24   f  designated aa, ab, ac, ad, ae, of in the tables. The six wave winding wires  24   a - 24   f  of the second single mat  44   b  are designated bg, bh, bi, bj, bk, bl. The a or b in the top row of each table thus designate the position a or b (single mat  44   a  or single mat  44   b ), and the letters a to 1 at the bottom of each row in the table designate the respective wave winding wire. 
     Table 1 shows the wire arrangement in the respective slot  16  for a coil mat  42  without conductor swap and without layer swap. For a coil mat  42  of this type without conductor swap and without layer swap and with the same number of individual wires n1=n2, the zone width corresponds to 0.5*n1=0.5*n2 and thus to half the number of individual wires. In the case of such a coil mat  42  without conductor swap and without layer swap, a flat mat  50  is produced by simple stacking. If a stair-shaped mat  54  is to be produced, the individual wave winding wires  24  in the individual mats  44   a ,  44   b  are plugged. Accordingly, the individual mats  44   a ,  44   b  are produced by plugging. 
     
       
         
           
               
             
               
                 TABLE 1 
               
               
                   
               
               
                 Wire arrangement in the slot - without conductor swap and without layer swap 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
            
               
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 e 
                 a 
               
               
                 a 
                 b 
                 c 
                 d 
                 e 
                 f 
                 a 
                 b 
                 c 
                 d 
                 e 
                 f 
                 a 
                 b 
                 c 
                 d 
                 e 
                 f 
                 a 
                 b 
                 c 
                 d 
                 a 
                 f 
               
               
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
               
               
                 g 
                 h 
                 i 
                 j 
                 k 
                 l 
                 g 
                 h 
                 i 
                 j 
                 k 
                 l 
                 g 
                 h 
                 i 
                 j 
                 k 
                 l 
                 g 
                 h 
                 i 
                 j 
                 k 
                 l 
               
               
                   
               
            
           
         
       
     
     In the following table 2, a winding scheme for a coil mat  42  with conductor swap and without layer swap is explained. 
     For the coil mat  42  with conductor swap and without layer swap, the zone width corresponds to the number n 1 =n 2  of the individual wires. A flat mat  50  having this winding scheme can be produced by stacking. A stair-shaped mat  54  having this winding scheme can be produced by plugging the individual wires. 
     
       
         
           
               
             
               
                 TABLE 2 
               
               
                   
               
               
                 Wire arrangement in the slot - with conductor swap and without layer swap 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
            
               
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
               
               
                 a 
                 b 
                 c 
                 d 
                 e 
                 f 
                 b 
                 a 
                 d 
                 c 
                 f 
                 e 
                 a 
                 b 
                 c 
                 d 
                 e 
                 f 
                 b 
                 a 
                 d 
                 c 
                 f 
                 e 
               
               
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
               
               
                 g 
                 h 
                 i 
                 j 
                 k 
                 l 
                 h 
                 g 
                 j 
                 i 
                 l 
                 k 
                 g 
                 h 
                 i 
                 j 
                 k 
                 l 
                 h 
                 g 
                 j 
                 i 
                 i 
                 k 
               
               
                   
               
            
           
         
       
     
     The following table 3 shows the winding scheme of a coil mat  42  without conductor swap and with layer swap. The zone width of a coil mat  42  having this winding scheme corresponds to twice the number 2n 1 =2n 2  of the individual wires. A flat mat  50  is possible by plugging the individual mats  44   a ,  44   b . A stair-shaped mat  54  can be produced by plugging the individual mats  44   a ,  44   b  and cross-plugging of the individual wave winding wires  24 . 
     
       
         
           
               
             
               
                 TABLE 3 
               
               
                   
               
               
                 Wire arrangement in the slot - without conductor swap and with layer swap 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
            
               
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
               
               
                 a 
                 b 
                 c 
                 d 
                 e 
                 f 
                 a 
                 b 
                 c 
                 d 
                 e 
                 f 
                 g 
                 h 
                 i 
                 j 
                 k 
                 l 
                 g 
                 h 
                 i 
                 j 
                 k 
                 l 
               
               
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
               
               
                 g 
                 h 
                 i 
                 j 
                 k 
                 l 
                 g 
                 h 
                 i 
                 j 
                 k 
                 l 
                 a 
                 b 
                 c 
                 d 
                 e 
                 f 
                 a 
                 b 
                 c 
                 d 
                 e 
                 f 
               
               
                   
               
            
           
         
       
     
     The following table 4 shows the winding scheme of a coil mat  42  with conductor swap and with layer swap. The zone width corresponds to twice the number 2n1=2n2 of the individual wave winding wires. A flat mat  50  can be produced with this winding scheme by plugging the individual mats  44   a ,  44   b . A stair-shaped mat  54  can be produced with this winding scheme by plugging the individual mats  44   a ,  44   b  and cross-plugging of individual wave winding wires  24 . 
     
       
         
           
               
             
               
                 TABLE 4 
               
               
                   
               
               
                 Wire arrangement in the slot - with conductor swap and with layer swap 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
            
               
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
               
               
                 a 
                 b 
                 c 
                 d 
                 e 
                 f 
                 b 
                 a 
                 d 
                 c 
                 f 
                 e 
                 g 
                 h 
                 i 
                 j 
                 k 
                 l 
                 h 
                 g 
                 j 
                 i 
                 l 
                 k 
               
               
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 b 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
                 a 
               
               
                 g 
                 h 
                 i 
                 j 
                 k 
                 l 
                 h 
                 g 
                 j 
                 i 
                 l 
                 k 
                 a 
                 b 
                 c 
                 d 
                 e 
                 f 
                 b 
                 a 
                 d 
                 c 
                 f 
                 e 
               
               
                   
               
            
           
         
       
     
     Methods for manufacturing the coil mats  42  in accordance with the above-explained winding schemes are described in more detail in the following. With reference to  FIGS. 6 and 7 , the design of the individual wave winding wires  24  is first described in more detail, then a device and a method for providing such wave winding wires are explained with reference to  FIGS. 8 to 14 , and then different winding head shapes  1  to  6  to be created using these devices and methods are explained with reference to  FIGS. 15 a  to 15 f   .  FIGS. 16 to 21  are then used to explain the manufacture of a winding mat  40  representing one of the individual mats  44   a ,  44   b  by plugging the wave winding wires  24 .  FIGS. 22 to 24  are then used to explain how to make a coil mat  42  by plugging the individual mats  44   a ,  44   b . Then the process of cross-plugging is explained with reference to  FIGS. 25 a  to 25 d   .  FIGS. 26 to 28  then show three specific embodiments of the coil mat  42 ; a manufacture of the coil winding  20  and its connection are then explained with reference to  FIGS. 29 to 33 . 
       FIG. 6  shows a plan view of first winding heads  30   a  of a pair of wave winding wires  24 ,  24   a ,  24   b , and  FIG. 7  shows a perspective view of second winding heads  30   b  of the pair of wave winding wires  24 ,  24   a ,  24   b . The first winding head  30   a  of the first wave winding wire  24   a  is designed in such a way that a coil step of 7 is obtained, whereas the first winding head  30   a  provides for a coil step of 5 for the second wave winding wire  24   b . Accordingly, a coil step of 5 is provided for the second winding head  30   b  of the first wave winding wire  24   a , whereas a coil step of 7 is provided for the second winding head  30   b  of the second wave winding wire  24   b . Thus, a coil step of 5-7 and a total coil width of 6 are achieved. 
     The winding heads  30  have a central roof bend  58  at the second bend point  34   b  and a transition bend  60   a ,  60   b  at the first bend point  34   a  and at the third bend point  34   c . Between the transition bend  60   a ,  60   b  and the roof bend  58 , the respective connecting section  36  is provided. The region of the first transition bend  60   a  forms a first winding head section  62   a , the region of the roof bend  58  forms a second winding head section  62   b , and the region of the second transition bend  60   b  forms a third winding head section  62   c . Each connecting section  36  also has a counter-bend  64 . 
     The individual wave winding wires  24  are basically the same for all variants of winding mats  40  and also for coil mats  42 . They are each formed from a profile wire and in particular from a rectangular profile wire. The Z-height offsets  38   a ,  38   b ,  38   c , which will be explained in more detail below, can differ in the individual wave winding wires  24 ,  24   a ,  24   b . Both the direction and height of the height offset  38   a ,  38   b ,  38   c  can vary. Each height offset  38   a ,  38   b ,  38   c  can be directed in a first height direction HR 1  or in a second height direction HR 2 . The first height direction HR 1  can, for example, extend in the Z-direction so that it corresponds to the direction radially outwards when the coil mat  42  is used as intended in the component  12 ; the second height direction HR 2  is directed opposite to the first height direction HR 1  and can, for example, extend in the Z-direction so that it corresponds to the direction radially inwards when the coil mat  42  is used as intended in the component  12 . The amount of the height of the height offsets  38   a ,  38   b ,  38   c  corresponds in particular to a half or a whole height extension dimension HM. The height extension dimension HM corresponds to the extension of each straight wire section  28  in the Z-direction (height direction) plus a predetermined tolerance value. The tolerance value takes into account a play/room between adjacent wires and any other distances selected for design reasons. 
     With regard to the winding head shape, which can be characterized by the respective direction and the respective height of the height offsets  38   a ,  38   b ,  38   c  in the winding head  30 , each wave winding wire  24  can differ within a coil mat  42  and a winding mat  40 . Each individual wave winding wire  24  can also have different winding head shapes at different winding heads  30 . 
     The winding head  30  of the wave winding wires  24  has a roof shape with a slight counter-bend  64 , as explained above. The height offsets  38   a ,  38   b ,  38   c  are bent into the wave winding wire  24  at the three bending points  34   a ,  34   b ,  34   c .  FIGS. 15 a  to 15 f    show that these differ in height and direction. The counter-bending  64  allows more space for bending the height offsets  38   a ,  38   b ,  38   c  without increasing the winding head height WKH (extension of the winding head  30  in the Y-direction). Furthermore, no wave winding wire  24  is twisted at any point of time. The orientation of the upper surface OF and the lower surface UF remains the same along the neutral fiber. 
     In the following, reference is made to  FIGS. 8 to 14  for a more detailed description of a wave winding wire supply device  66  for supplying the wave winding wires  24 ,  24   a ,  24   b . The wave winding wire supply device  66  comprises a wave winding wire manufacturing device  68  and a winding head shaping device  70  for shaping the winding heads  30 ,  30   a ,  30   b.    
     The wave winding wire manufacturing device  68  is merely indicated by an arrow in  FIG. 11  and is not shown in detail. The wave winding wire manufacturing device  68  is designed as described and shown in German patent application DE 10 2017 127 634.3 to which reference is expressly made for further details. The wave winding wires  24 ,  24   a ,  24   b  are accordingly produced as a flat winding in one plane, with the transition bends  60   a ,  60   b  and roof bends  58  as well as the counter-bends  64  being created in the winding heads  30 ,  30   a ,  30   b  at the bend points  34   a ,  34   b ,  34   c . This bending operation is carried out with appropriately selected bending elements in such a way that the winding heads  30 ,  30   a ,  30   b  provide the respectively desired shift dimensions and thus coil steps between the straight wire sections  28  plus an amount in the X direction which corresponds to the change in the extension of the winding head  30  in the X direction when the height offsets  38   a ,  38   b ,  38   c  are introduced. In this still flat state, the wave winding wires  24 ,  24   a ,  24   b  are fed to the winding head shaping device  70  individually or as a group, in particular as a pair of wave winding wires  24   a ,  24   b , as shown in the exemplary embodiment. 
     The winding head shaping device  70  comprises a clamping device  72  shown in  FIGS. 8 to 10 and 12  and having a first to fifth clamping unit  74 - 1 ,  74 - 2 ,  74 - 3 ,  74 - 4 ,  74 - 5 . 
     The first clamping unit  74 - 1  is a central clamping unit for holding the straight wire sections  28 , between which the winding heads  30 ,  30   a ,  30   b  are located which are to be provided with the height offsets  38   a ,  38   b ,  38   c  in the winding head shaping device  70 . In the embodiment shown, the first and second winding heads  30   a ,  30   b  of a wave section  26  can be shaped simultaneously. For this purpose, the first clamping unit  74 - 1  has a first clamping jaw  76   a  and a second clamping jaw  76   b , which are designed for simultaneously clamping and holding three adjacent straight wire sections  28  of the wave winding wires  24   a ,  24   b  to be shaped simultaneously. For this purpose, the clamping jaws  76   a ,  76   b  have flat clamping surfaces  92 - 1  which are pressed against the upper surface OF or the lower surface UF of the straight wire sections  28  and thus hold the straight wire sections  28  on one plane. 
     The second to fifth clamping units  74 - 2 ,  74 - 3 ,  74 - 4 ,  74 - 5  each have a first bending jaw  78   a  and a second bending jaw  78   b , one of which is individually shown in  FIG. 13 . Each bending jaw  78   a ,  78   b  has a fixing portion  80  and a shaping portion  82 . Flat clamping surfaces  92 - 2  and  92 - 3  for clamping the connecting sections  36 , and bending dies  84  having bending radii  86  are provided on the shaping section  82  formed on a cantilever in order to gently shape the bending points  34   a ,  34   b ,  34   c , i.e. to provide them with the height offsets  38   a ,  38   b ,  38   c . This causes the wire to be bent at the bend points  38   a ,  38   b ,  38   c . The wave head shaping device  70  is thus designed as an offsetting device. 
     Each clamping jaw  76   a ,  76   b  and each bending jaw  78   a ,  78   b  of each of the clamping units  74 - 1 ,  74 - 2 ,  74 - 3 ,  74 - 4 ,  74 - 5  can be moved in the Z-direction by its own actuator  88 - 1   a ,  88 - 1   b ,  88 - 2   a ,  88 - 2   b ,  88 - 3   a ,  88 - 3   b ,  88 - 4   a ,  88 - 4   b ,  88 - 5   a ,  88 - 5   b . Each actuator  88 - 1   a ,  88 - 1   b ,  88 - 2   a ,  88 - 2   b ,  88 - 3   a ,  88 - 3   b ,  88 - 4   a ,  88 - 4   b ,  88 - 5   a ,  88 - 5   b  can be individually controlled by a control unit  90 . Movement patterns for the actuators  88 - 1   a ,  88 - 1   b ,  88 - 2   a ,  88 - 2   b ,  88 - 3   a ,  88 - 3   b ,  88 - 4   a ,  88 - 4   b ,  88 - 5   a ,  88 - 5   b  for creating one of six winding head shapes  1 ,  2 ,  3 ,  4 ,  5 ,  6  (shown in  FIGS. 15 a  to 15 f   ) are stored in the control unit  90 . Which of the winding head shapes  1 ,  2 ,  3 ,  4 ,  5 ,  6  is to be created, results from the selected winding scheme and is explained in more detail below using three design examples  42 - 1 ,  42 - 2 ,  42 - 3  for the coil mat  42  shown in the  FIGS. 26-28 . 
     The winding head shaping device  70  shown in  FIGS. 8 to 13  is a device for bending the height offsets  38   a ,  38   b ,  38   c . One function of the winding head shaping device  70  is to clamp individual sections  28 ,  62   a ,  62   c  of the individual wave winding wires  24   a ,  24   b  individually and to move them individually in the Z-direction. In this manner, all height offsets  38   a ,  38   b ,  38   c  are bent simultaneously. The jump height can be adjusted in a variable manner. In order to cover all possible winding head shapes  1  to  6  described in the following, clamping at three points is provided at the three clamping surfaces  92 - 1 ,  92 - 2 ,  92 - 3  at the same time—especially at the straight wire sections  28 , the first winding head section  62   a  and the third winding head section  62   c —for each winding head  30 ,  30   a ,  30   b . The clamping force or even a specific clearance can be adjusted. 
       FIG. 8  shows an arrangement of a first clamping surface  92 - 1 , a second clamping surface  92 - 2  and a third clamping surface  92 - 3 , using the shaping of the first winding head  30   a  as an example. The first clamping surface  92 - 1  is arranged on one of the clamping jaws  76   a ,  76   b  of the first clamping unit  74 - 1 , the second clamping surface  92 - 2  is arranged on a bending jaw  78   a ,  78   b  of the second clamping unit  74 - 2 , and the third clamping surface  92 - 3  is arranged on a bending jaw  78   a ,  78   b  of the third clamping unit  74 - 3 . It can be seen that it is possible to bend one wave winding wire or several parallel wave winding wires  24   a ,  24   b  at a time. 
     In order to avoid a change in cross-section, the wire is free in space at the bending points  34   a ,  34   b ,  34   c  between the clamping surfaces  92 - 1 ,  92 - 2 ,  92 - 3 . This prevents the theoretical elongation of the neutral fiber by a change of the radius at the point of the height offset  38   a ,  38   b ,  38   c.    
     A respective winding head  30 ,  30   a ,  30   b  is shaped by a bending unit  86 . Each bending unit  86  has two opposite linear actuators, e.g. the actuators  88 - 2   a ,  88 - 2   b ,  88 - 3   a  and  88 - 3   b  for shaping the first winding head  30   a  using mirrored clamping jaws—e.g. the first bending jaw  78   a  of the second clamping unit  74 - 2  and the first bending jaw  78   a  of the third clamping unit  74 - 3  as well as the second bending jaw  78   b  of the second clamping unit  74 - 2  and the second bending jaw  78   b  of the third clamping unit  74 - 3 —for shaping the first winding head  30   a , as shown in  FIGS. 9 and 10 . 
     Therefore, for bending a winding head  30   a , only three clamping units  74 - 1 ,  74 - 2 ,  74 - 3  are used at each time. After each bending operation, the wave winding wire or, as here, the group of winding wires  24   a ,  24   b  is clocked to move on around a winding head on a carriage  96 . If the winding head shaping device  70  is designed with several bending units  86  arranged side by side, any number of winding heads  30 ,  30   a ,  30   b  can be shaped simultaneously, up to simultaneously bending all winding heads  30 . 
       FIG. 13  shows the design of the bending jaws  78   a ,  78   b  of the second to fifth clamping units  74 - 2  to  74 - 5  using the first bending jaw  78   a  of the second clamping unit  74 - 2  as an example. The bending jaw  78   a  has a flat clamping surface—here e.g. the second clamping surface  92 - 2 —used for clamping the wire. In addition, at the edges which cross the wire, the bending jaw  78   a  has bending radii  86  for creating the height offsets  38   a ,  38   b ,  38   c .  FIG. 13  shows one of the bending jaws  78   a  having the clamping surface  92 - 2  and two bending radii  86 . 
       FIGS. 11 and 12  show how the basic structure of the winding head shaping device  70  for bending the height offsets in the winding heads can look like. Here five clamping units  74 - 1 ,  74 - 2 ,  74 - 3 ,  74 - 4 ,  74 - 5  are arranged in such a way that two clamping units  74 - 2 ,  74 - 3  and  74 - 4 ,  74 - 5  on each side bend the first winding head  30   a  or the second winding head  30   b , and a clamping unit  74 - 1  in the middle serves to hold down the straight wire sections. 
       FIG. 14  shows the flow chart for introducing the height offsets  38   a ,  38   b ,  38   c  into the first and second winding heads  30   a ,  30   b  of a wave section  26  of the wave winding wires  24   a ,  24   b  using the winding head shaping device  70  shown in  FIGS. 11 and 12 . For example, the height offsets  38   a ,  38   b ,  38   c  are introduced in accordance with one of the winding head shapes shown in  FIGS. 15 a  to 15 f   . In a method for introducing the height offsets in accordance with a first winding head shape  1  shown in  FIG. 15 a    or a second winding head shape  2  shown in  FIG. 15 b   , the steps are as follows: 
     S 1  Clamping
         S 1   a  first clamping unit  74 - 1  clamps straight wire sections   S 1   b  second to fifth clamping units  74 - 2  to  74 - 5  clamp the flat connecting sections  36  at the winding head sections  62   a ,  62   c          

     S 2  Offsetting
         S 2   a  the bending jaws  78   a ,  78   b  of the second to fifth clamping units  74 - 2  to  74 - 5  move in the Z-direction in the clamped state, whereby height offsets  38   a ,  38   b ,  38   c  are created       

     S 3  Releasing
         S 3   a  releasing the first clamping unit  74 - 1     S 3   b  releasing the second to fifth clamping unit  74 - 2  to  74 - 5         

     An alternative procedure is carried out on introducing height offsets  38   a ,  38   b ,  38   c  in accordance with a third to sixth winding head shape  3  to  6  ( FIG. 15 c    to  15   f ). For this alternative procedure, the steps in  FIG. 14  are: 
     S 1  Clamping
         S 1   a  first tensioning unit  74 - 1  clamps straight wire sections   S 1   b  second to fifth clamping units  74 - 2  to  74 - 5  clamp the flat connecting sections  36  at the winding head sections  62   a ,  62   c          

     S 2  Offsetting
         S 2   a  the bending jaws  78   a ,  78   b  of the second to fifth clamping units  74 - 2  to  74 - 5  move in the Z-direction in the clamped state, whereby height offsets  38   a ,  38   b  are created   S 2   b  releasing the first clamping unit  74 - 1 , and the bending jaws  78   a ,  78   b  of the second to fifth clamping units  74 - 2  to  74 - 5  move in the Z-direction, thereby creating the height offset  38   b          

     S 3  Releasing
         S 3   b  releasing the second to fifth clamping unit  74 - 2  to  74 - 5 .       

     Accordingly, step S 2   b  described in this alternative is optional, which is indicated by the brackets in  FIG. 14 . In this alternative, step S 3   a  is carried out as a part of step S 2   b.    
     Then the wave winding wires  24   a ,  24   b  are moved on in the longitudinal direction of the wave winding wires  24   a ,  24   b , i.e. the X-direction, by the length of a wave section  26  on the carriage  96 , and the sequence illustrated in  FIG. 14  is repeated for the next wave section  26  until all winding heads  30 ,  30   a ,  30   b  are shaped corresponding to a specification. Examples of such specifications are still explained in more detail below. 
     During bending of the winding heads  30 ,  30   a ,  30   b  as described above, the height offsets  38   a ,  38   b ,  38   c  are formed in such a way that one of the winding head shapes  1 ,  2 ,  3 ,  4 ,  5  and  6  shown in  FIGS. 15 a  to 15 f    is created.  FIGS. 15 a  to 15 f    schematically show a section through the corresponding wave winding wire  24 , similar to  FIG. 5 , with the straight wire sections  28  and the intermediate wave winding head  30  having the height offsets  38   a ,  38   b ,  38   c  being shown. 
     In order to produce the above-describe coil mats  42  with different winding schemes, six different winding head shapes  1  to  6  are provided in the configuration shown in  FIGS. 15 a  to 15 f   .  FIGS. 15 a  to 15 f    show the plan view of different winding head shapes  1  to  6  of the winding head  30  (in the y-direction of  FIG. 7 ). The viewing direction is such that the left straight wire section  28  comes first when tracing the conductor. Using the first winding head shape  1  as an example: if you trace the conductor, you first proceed radially inwards (example for the second height direction HR 2 ) along a height offset by half a jump (half the height extension dimension HM), then radially outwards (example for the first height direction HR 1 ) by a full jump (full height extension dimension HM) and then again radially inwards by half a jump (half the height extension dimension HM). 
     Each wave winding wire  24 ,  24   a ,  24   b  has a wire thickness in the straight wire sections  28  which, measured in a height direction (Z-direction) running transversely to the longitudinal direction (X direction) and transversely to the transverse direction (Y direction), extends almost over the height extension dimension HM, i.e. the height extension dimension HM corresponds to the wire thickness of the straight wire sections  28 , measured in the height direction, plus a predetermined tolerance. 
     In each winding head  30 , the first height offset  38   a  extends over half a height extension dimension HM and is provided at the first winding head section  62   a  which connects to the first straight wire section  28   a . In particular, the first height offset  38   a  is provided in the first transition bend  60   a . In addition, in each winding head  30 , the second height offset  38   b  extends over an entire height extension dimension HM at each winding head  30  and is provided at the second winding head section  62   b  which connects to the first winding head section  62   a . In particular, the second height offset  38   b  is provided in the roof bend  58 . For each winding head  30 , the third height offset  38   c  extends over half a height extension dimension HM and is provided at the third winding head section  62   c  which extends between the second winding head section  62   b  and a second straight wire section  28   b . In particular, the third height offset  38   c  is provided in the second transition bend  60   b . Accordingly, the height of the first and the third height offsets  38   a ,  38   c  is equal to half a height extension dimension HM for all winding head shapes  1  to  6 , and the height of the second height offset  38   b  is equal to a full height extension dimension HM for all winding head shapes  1  to  6 . However, the height direction is different for the individual height offsets  38   a ,  38   b ,  38   c  of the first to sixth winding head shapes  1  to  6 . 
     Each of the height offsets  38   a ,  38   b ,  38   c  is directed either in the first height direction HR 1  or in the second height direction HR 2 . The first height direction HR 1  corresponds to either the radially outward or the radially inward direction when the winding mat  40  or the coil mat  42  are used as intended, and the second height direction HR 2  is correspondingly directed in the other direction. In the embodiment shown here, the first height direction HR 1  corresponds to the direction radially outwards and the second height direction HR 2  corresponds to the direction radially inwards. 
       FIG. 15 a    shows a first winding head shape  1  in which the first height offset  38   a  is directed in the second height direction HR 2 , the second height offset  38   b  is directed in the first height direction HR 1 , and the third height offset  38   c  is directed in the second height direction HR 2 . 
     In  FIG. 15 b   , a second winding head shape  2  is shown in which the first height offset  38   a  is directed in the first height direction HR 1 , the second height offset  38   b  is directed in the second height direction HR 2 , and the third height offset  38   c  is directed in the first height direction HR 1 . 
     As shown in  FIGS. 15 a  and 15 b   , the first and second straight wire sections  28   a ,  28   b  are in the same plane for the first and the second winding head shapes  1 ,  2 . The first and the second winding head shape  1 ,  2  shall be provided in particular for the standard regions  56 . 
       FIG. 15 c    shows a third winding head shape  3  in which the first height offset  38   a  is directed in the first height direction HR 1 , the second height offset  38   b  is directed in the first height direction HR 1 , and the third height offset  38   c  is directed in the second height direction HR 2 . 
     In  FIG. 15 d    a fourth winding head shape  4  is shown in which the first height offset  38   a  is directed in the first height direction HR 1 , the second height offset  38   b  is directed in the second height direction HR 2 , and the third height offset  38   c  is directed in the second height direction HR 2 . 
     In  FIG. 15 e    a fifth winding head shape  5  is shown in which the first height offset  38   a  is directed in the second height direction HR 2 , the second height offset  38   b  is directed in the first height direction HR 1 , and the third height offset  38   c  is directed in the first height direction HR 1 . 
     In  FIG. 15 f    a sixth winding head shape  6  is shown in which the first height offset  38   a  is directed in the second height direction HR 2 , the second height offset  38   b  is directed in the second height direction HR 2 , and the third height offset  38   c  is directed in the first height direction HR 1 . 
     As can be seen in the  FIGS. 15 c  to 15 f   , the left and right straight wire sections  28  are offset by a height offset dimension HM in either the first height direction HR 1  or the second height direction HR 2  in the third to sixth winding head shapes  3  to  6 . The third to sixth winding head shapes  3  to  6  shall therefore be provided in those areas where such an offset of adjacent straight wire sections  28  is to be provided, which may be the case in particular in the start region  46 , the end region  48  or the transition region  52 . 
     After the wave winding wires  24 ,  24   a ,  24   b  have been manufactured and supplied accordingly by the wave winding wire supply device  66 , they are joined together to form a winding mat  40  to form the first individual mat  44   a  and the second individual mat  44   b . Depending on the winding scheme, the wave winding wires  24  are joined together by stacking STP or plugging STK or by cross-plugging. 
     For stacking the coil mat  42 , the individual mats  44   a ,  44   b  are laid on top of each other one after the other. It is provided in this case that always two Z-height offsets formed downwards (in the second height direction HR 2 ) lie one above the other, because otherwise the winding head  30  builds up radially. The same applies to the stacking of the individual wave winding wires  24 . The height offsets  38   a ,  38   b ,  38   c  of the individual wave winding wires  24  are formed in such a way that the same individual wire is always on top at all crossing points. 
     In the following, plugging of the wave winding wires  24  is explained in more detail with reference to the illustrations in  FIGS. 16 to 21 .  FIGS. 16 to 18  show different stages in plugging a first wave winding wire  24   a  and a second wave winding wire  24   b .  FIG. 19  illustrates plugging of further wave winding wires  24   c ,  24   d ,  24   e  and  24   f  in addition to the already plugged pair of wave winding wires  24   a ,  24   b .  FIG. 20  shows the winding mat  40  obtained by plugging in accordance with  FIGS. 16 to 19 . 
     The plugging of the individual wave winding wires  24   a  to  24   f  takes place in several steps. This serves to produce individual mats  44   a ,  44   b  in which the same wire does not necessarily have to be on top at the crossing points. First, a sub-section of the individual wave winding wires  24   a ,  24   b  is always pushed up or down as shown in  FIG. 16 . The sub-section that is pushed down is shown as a dashed line, the sub-section that is pushed up is shown as a solid line. 
     As shown in  FIG. 16 , a first sub-section  98 - 1   a  of the first wave winding wire  24   a  is pushed up and an adjacent second sub-section  98 - 2   a  of the first wave winding wire  24   a  is pushed down. At the second wave winding wire  24   b , a first sub-section  98 - 1   b  of the first wave winding wire  24   a  is pushed down and an adjacent second sub-section of the second wave winding wire  24   b  is pushed up, respectively. The extension of the sub-sections  98 - 1   a ,  98 - 2   a  over the wave winding wire  24   a  may be different and may be between a half-wave section  32   a  and the full length of the wave winding wire  24   a  minus a half-wave section  32   a . In the example shown, the first and second sub-sections  98 - 1   a ,  98 - 2   a ,  98 - 1   b ,  98 - 2   b  each comprise a wave section  26  and are alternately provided over the length of the respective wave winding wire  24   a ,  24   b.    
     The two wave winding wires  24   a ,  24   b  are then plugged into one another as shown in  FIG. 17 . 
     With the sub-sections  98 - 1   a ,  98 - 2   a ,  98 - 1   b ,  98 - 2   b  pushed up and down accordingly, the first and the second wave winding wires  24   a ,  24   b  are pushed into each other in the transverse direction as indicated by arrows in  FIG. 16  so that, as shown in  FIG. 17 , the respective first sub-section  98 - 1   a  of the first wave winding wire  24   a  is pushed over the respective first sub-section  98 - 1   b  of the second wave winding wire  24   b  while the respective second sub-section  98 - 2   a  of the first wave winding wire  24   a  is pushed under the second sub-section  98 - 2   b  of the first wave winding wire  24   b.    
     Once the wires are completely plugged into each other, all sections of the wave winding wires  24   a ,  24   b  jump back to their original plane, resulting in all straight wire sections  28  being on one plane. This is illustrated in  FIG. 18 . It can be seen that the winding heads  30 ,  30   a ,  30   b  form crossing points  100  in different planes and all straight wire sections  28  are in one plane, as can be seen from the line styles. Double dotted lines are used to show wire sections that lie in the plane  0 , in which all straight wire sections  28  lie. The solid lines show wire sections that lie in an upper plane offset upwards (i.e. in the first height direction HR 1 ) from the plane  0  by half a height extension dimension HM, and the dashed lines show wire sections that lie in a lower plane downwardly offset from the plane  0  by half a height extension dimension HM in the second height direction HR 2 . 
     In the finished plugged position as shown in  FIG. 18 , the wave winding wires  24   a  and  24   b  are aligned with each other so that their longitudinal center lines are on top of each other. This layer is also referred to as the alignment layer. 
     This plugging process, which is explained using a first and a second wave winding wire  24   a ,  24   b , is repeated until the entire winding mat  40  and thus one of the individual mats  44   a ,  44   b  is achieved. In  FIG. 19 , this is illustrated using the example of six wave winding wires  24   a  to  24   f .  FIG. 20  then shows in a diagram corresponding to  FIG. 18  the winding mat  40  thus produced, with the crossing points  100  and the straight wire sections  28  in a common plane. 
       FIGS. 16 to 20  show the plugging of wave winding wires  24  with the same coil step. 
     As explained in  FIGS. 1 and 6 to 14 , the wave winding wires  24  can also be produced in pairs with different coil steps (here  5 - 7 ). 
     As shown in  FIG. 21 , the wave winding wires  24   a ,  24   b  can also always be plugged pairwise with different coil steps using the same principle as explained in  FIGS. 16 to 20  for individual wave winding wires  24   a - 24   f  with the same coil step. 
     It can be readily seen that such a plugging of wave winding wires  24   a  to  24   f  can be easily automated. A plugging device of a winding mat manufacturing device not shown in detail only requires a movement device for moving the wave winding wires  24   a  and  24   b  towards each other, whereby the sub-sections  98 - 1   a ,  98 - 1   b ,  98 - 2   a  and  98 - 2   b  are to be pushed upwards or downwards, for example, by means of corresponding sliding guides or grippers. 
     When the individual mats  44   a ,  44   b  have been produced in this way, the coil mat  42  can be made from them. For this purpose, the individual mats  44   a ,  44   b  can be stacked or also plugged, as shown in  FIGS. 22 to 24 . 
     When plugging the individual mats  44   a ,  44   b , again a first sub-section  102 - 1   a  of the first individual mat  44   a  is pushed up and an adjacent second sub-section  102 - 2   a  of the first individual mat  44   a  is pushed down. For the second individual mat  44   b , a corresponding first sub-section  102 - 1   b  is pushed down and a corresponding second sub-section  102 - 2   b  is pushed up. Then the individual mats  44   a ,  44   b  are pushed into each other so that the first sub-section  102 - 1   a  of the first individual mat  44   a  is pushed over the first sub-section  102 - 1   b  of the second individual mat  44   b  and the second sub-section  102 - 2   a  of the first individual mat  44   a  is pushed under the second sub-section  102 - 2   b  of the second individual mat  44   b.    
     In order that the individual mats  44   a ,  44   b  can be plugged into each other in this way, they cannot have any layer swap on the plug-in side (the respective side to be pushed into the other individual mat). As shown in  FIG. 21 , when plugging the coil mat  42 , the layer swap must therefore always take place on the same side of the individual mats  44   a  or  44   b . This means that the wave winding wires  24   a  to  24   f  can change their position in every second winding head  30  at maximum. Accordingly, in one individual mat  44   a , a layer swap can only take place in the first winding heads  30   a , and in the other individual mat  44   b , a layer swap can only take place in the second winding heads  30   b.    
     As shown in  FIG. 22 , the winding heads  30  are offset downwards and upwards in relation to each other to facilitate plugging.  FIG. 22  shows the individual mats  44   a ,  44   b  before plugging. 
       FIG. 23  shows the step of pushing the sub-sections  102 - 1   a ,  102 - 1   b ,  102 - 2   a  and  102 - 2   b  into each other. In particular,  FIGS. 23 and 23   a  show the two individual mats  44   a ,  44   b  in a half-inserted state. 
     The two individual mats  44   a ,  44   b  can be plugged into each other on both sides so that the number of individual wires required for an individual mat  44   a ,  44   b  is always alternately located in the upper or lower layer of the coil mat  42  at least twice. This results in the layer swap in the coil mat  42 . 
       FIG. 24  shows the finished plugged coil mat  42 . In  FIG. 24 , plugging of the individual mats  44   a ,  44   b  is completed. The longitudinal center lines of the individual mats  44   a ,  44   b  lie on top of each other; this layer is also called the alignment layer. 
     It is readily apparent that this type of plugging individual mats  44   a ,  44   b  can also be easily automated. A plugging device (not further illustrated) of a coil mat manufacturing device only requires a movement device for moving the individual mats  44   a ,  44   b  towards each other, wherein the sub-sections  102 - 1   a ,  102 - 1   b ,  102 - 2   a  and  102 - 2   b  are to be pushed upwards or downwards, for example, by means of corresponding sliding guides or grippers. 
     In the following, cross-plugging is described in more detail with reference to  FIGS. 25 a  to 25 d   , using two pairs of wave winding wires  24   a ,  24   b  and  24   c ,  24   d.    
     Cross-plugging is intended if a layer swap is to take place on both sides of the individual mat  44   a ,  44   b . Cross-plugging is suitable for both individual mats  44   a ,  44   b  and individual wires—wave winding wires  24 ,  24   a - f . Cross-plugging is carried out in four steps that are explained in  FIGS. 25 a  to 25 d    below. 
       FIG. 25 a    shows as a first step straight plugging. In this first step, plugging is carried out as described above. At the point K 2  where cross-plugging is to be carried out, a central winding head K 2  and the adjacent winding head K 1  and K 3  respectively preceding and following said central winding head K 2 , are in one plane. If cross-plugging is desired at the position of winding head K 2  in  FIGS. 25 a  to 25 d   , the respective winding head at the positions K 1 , K 2  and K 3  of the respective individual mat  44   a  is positioned in one plane (solid at the top, dashed at the bottom), as shown in  FIG. 25   a.    
       FIG. 25 b    shows the second step—overplugging. In contrast to plugging, the wave winding wires  24   a ,  24   b  on the one hand and  24   c ,  24   d  on the other hand are pushed into each other until the winding heads  30   a ,  30   b  are at the stop. Accordingly, the wave winding wires  24   a ,  24   b  are thus pushed beyond their alignment position until the winding heads  30   a ,  30   b  stop. 
     As shown in  FIGS. 25 b  and 25 c   , thereafter, the third step—swap—takes place. The two central winding heads at position K 2  are pushed upwards until the winding head previously positioned on the lower plane is now positioned on the upper plane. Thus, a layer swap takes place at position K 2 . 
     Then, as shown in  FIGS. 25 c  and 25 d   , the fourth step—reverse plugging-takes place. The wave winding wires  24   a ,  24   b ,  24   c ,  24   d  are pushed together again until the straight wire sections  28  of the winding mat  40  again lie exactly side by side, as shown in  FIG. 25 d   -alignment position. 
     Embodiments of the Coil Mats  42 —Mat Designs: 
     In the following, different exemplary embodiments  42 - 1 ,  42 - 2  and  42 - 3  of coil mats  42  are explained in more detail with reference to the illustrations in  FIGS. 26, 27 and 28 . In this case, different exemplary embodiments  42 - 1 ,  42 - 2 ,  42 - 3  of the coil mat  42  manufactured according to the criteria and processes outlined above are described in greater detail. Three exemplary coil mats  42  are shown in  FIGS. 26, 27 and 28 . The individual mats  44   a ,  44   b  are shown in black and white. The x indicates that the conductors enter into the drawing plane, the point indicates that the conductors exit from the plane. SA designates the outside of the stator  14 , and SI designates the inside of the stator. In addition, each array corresponds to the width of the average coil step. Therefore, each conductor-wave winding wires  24   a - 24   f —of an individual mat  44   a ,  44   b  is exactly once in each array of an individual mat  44   a ,  44   b . Both individual mats  44   a ,  44   b  are formed from wave winding wires  24  that are manufactured with different winding head shapes  1  to  6  shown in  FIGS. 15 a  to 15 f   . The arrays above and below the individual mats  44   a ,  44   b  represent the winding heads  30  that connect the straight wire sections  28  in the individual mats  44   a ,  44   b  to each other. The arrays present the winding head shapes  1 ,  2 ,  3 ,  4 ,  5  or  6  of  FIGS. 15 a  to 15 f    which are respectively provided and which develop when tracing a conductor from the start region  46  to the end region  48 . These are lined up in such a way that the winding head  30  builds up radially by a maximum of one wire thickness. Both individual mats  44   a ,  44   b  can be designed with a regular coil step as well as with an alternating coil step (for example of  5 - 7 ). 
     Each coil mat  42 ,  42 - 1 ,  42 - 2 ,  42 - 3  has a start region  46 , at least one standard region  56  and an end region  48 . Furthermore, the coil mat  42 ,  42 - 1 ,  42 - 2 ,  42 - 3  can have any number of standard regions  56 , each of which can be connected to a transition region  52 . The different embodiments  42 - 1 ,  42 - 2 ,  42 - 3  of the coil mat  42  have a first individual mat  44   a  and a second individual mat  44   b  and are designed in such a way that the same individual mat  44   a ,  44   b  never lies on top of itself when wound up. 
     The exemplary embodiments  42 - 1  and  42 - 2  of the coil mat  42  shown in  FIGS. 26 and 27  represent different versions of a coil mat  42  without layer swap. 
     The first exemplary embodiment  42 - 1  of the coil mat  42  shown in  FIG. 26  is designed in such a way that in each region always the same individual mat is on top-first individual mat  44   a —or bottom—second individual mat  44   b . This makes it possible to stack the two individual mats  44   a ,  44   b . The coil mat  42  of the first exemplary embodiment  42 - 1  is thus produced by stacking the individual mats  44   a ,  44   b . The first individual mat  44   a  is designed in such a way that it can be produced by stacking STP. The second individual mat  1 . 1 . 2  only needs to be plugged in the transition region  52  and in the end region  48 —as indicated by plugging STK—and can otherwise be assembled by stacking. 
     In the second exemplary embodiment  42 - 2  of the coil mat  42  shown in  FIG. 27 , all winding heads  30  are radially further out in order to gain more space in the rotor compartment for the connection. The second exemplary embodiment  42 - 2  of the coil mat  42  is also designed in such a way that in each region always the same individual mat is on top-first individual mat  44   a —or bottom—second individual mat  44   b . This makes it possible to stack the two individual mats  44   a ,  44   b . In this exemplary embodiment  42 - 2  of the coil mat  42 , the first individual mat  44   a  only needs to be plugged in the transition region  52  and in the end region  48  and can otherwise be assembled by stacking. The second individual mat  44   b  is designed in such a way that it can be produced by stacking STP. 
       FIG. 28  shows one exemplary embodiment  42 - 3  of a coil mat  42  with layer swap. In particular, in the currently preferred third exemplary embodiment  42 - 3  of the coil mat  42 , in each standard region  56  and in each transition region  52 , it can be freely selected which individual mat  44   a ,  44   b  is on top. In this case, both the first individual mat  44   a  and the second individual mat  44   b  are produced by plugging STK. The entire coil mat  42  is also of the plugged design by plugging the first and second individual mats  44   a ,  44   b  into each other. 
     All exemplary embodiments  42 - 1 ,  42 - 2 ,  42 - 3  of the coil mat  42  shown are independent of the direction of rotation when winding the coil mat  42  into the stator. They can be wound up clockwise and also counterclockwise. 
     The illustrated exemplary embodiments  42 - 1 ,  42 - 2 ,  42 - 3  of the coil mat  42  can also be produced in a mirrored fashion. For the mirrored versions on the stator outer side SA or the stator inner side SI, there is the “translation key” of the winding head shapes  1  to  6  from  FIGS. 15 a  to 15 f    shown in the following Table 5, which translation key applies to all versions. 
     
       
         
           
               
             
               
                 TABLE 5 
               
             
            
               
                   
               
               
                 Translation key for winding head shapes when mirroring 
               
               
                 the exemplary embodiments 42-1, 42-2, 42-3: 
               
            
           
           
               
               
            
               
                   
                 Becomes the winding head shape in 
               
               
                 Winding head shape of the 
                 the mirrored version of the 
               
               
                 exemplary embodiment shown: 
                 exemplary embodiment: 
               
               
                   
               
            
           
           
               
               
            
               
                 1 
                 2 
               
               
                 2 
                 1 
               
               
                 3 
                 6 
               
               
                 4 
                 5 
               
               
                 5 
                 4 
               
               
                 6 
                 3 
               
               
                   
               
            
           
         
       
     
     In the following, examples for the interconnection of the coil mats  42  for forming the coil winding  20  are explained in more detail with reference to the illustration in  FIGS. 29 to 32 . 
       FIG. 29  shows the end region  48  of a wave winding wire  24 . An exit for connection is normally formed by the last winding head  30  being accomplished only half at the end region  48 . The first winding head section  62   a  then forms the regular exit  104 . Instead of this regular exit  104 , a mirrored exit  106  is provided by providing the last half winding head  30 —first winding head section  62   a -correspondingly mirrored. 
     The connection of the first individual mat  44   a  and the second individual mat  44   b  can be carried out in the same way in all three exemplary embodiments  42 - 1 ,  42 - 2 ,  42 - 3  of the coil mat  42  and applies to both three-phase and multi-phase electric machines. If the two individual mats  44   a ,  44   b  are connected in series, the connection effort can be clearly minimized by the mirrored design of the last half winding head  30 , which has just been explained with reference to  FIG. 29 .  FIGS. 30 to 33  show that the conductor ends thus exit in pairs and can be connected to each other without additional connection elements.  FIG. 30  shows the rear view of the wound coil mat  42 , which is formed from wave winding wires  24   a - 24   f  using the same coil step (see  FIGS. 16 to 20 ), and shows in particular the interconnected coil winding  20  with uniform coil step formed from it. The series connection  108  is shown, with the exits  106  of a single mat  44   b  mirrored. Phase exits  110  and star points  112  are also shown. 
       FIG. 31  shows the rear view of the coil mat  42  with alternating coil step (see  FIGS. 1, 5 to 12 and 21 ) and in particular the connected coil winding  20  with alternating coil step formed from it. The series connection  108 , the phase outlets  110  and the star points  112  are also shown here. 
       FIG. 32  shows the front view of the connected coil winding  20  with uniform coil step and  FIG. 33  shows the front view of the connected coil winding  20  with alternating coil step. 
     With an alternating coil step, coil winding  20  can be connected in alternating coil step, or an even coil step can be performed at the connection point. The respective other ends of the conductors can be connected to the star point (or several star points) and/or the phase outlets, depending on the star or delta connection. Potential equalization is achieved by connecting the two individual mats  44   a ,  44   b  in series. 
     Preferred configurations of the invention relate to a method and a device for manufacturing winding mats for producing a coil winding for an electric machine. The winding mat is composed of wave winding wires bent as flat winding in one plane. In order to be able to produce different winding mats with improved electric characteristics easily and reliably in large series, it is proposed not to interlace or twist the wave winding wires, but to plug them at least partially. There are also proposed a method and a device for manufacturing a coil mat from one or several winding mats designed as individual mats. The device preferably comprises an offsetting device for introducing height offsets into winding heads of the wave winding wires. 
     While at least one exemplary embodiment of the present invention(s) is disclosed herein, it should be understood that modifications, substitutions and alternatives may be apparent to one of ordinary skill in the art and can be made without departing from the scope of this disclosure. This disclosure is intended to cover any adaptations or variations of the exemplary embodiment(s). In addition, in this disclosure, the terms “comprise” or “comprising” do not exclude other elements or steps, the terms “a” or “one” do not exclude a plural number, and the term “or” means either or both. Furthermore, characteristics or steps which have been described may also be used in combination with other characteristics or steps and in any order unless the disclosure or context suggests otherwise. This disclosure hereby incorporates by reference the complete disclosure of any patent or application from which it claims benefit or priority. 
     LIST OF REFERENCE SIGNS 
     
         
           1  first winding head shape 
           2  second winding head shape 
           3  third winding head shape 
           4  fourth winding head shape 
           5  fifth winding head shape 
           6  sixth winding head shape 
           10  housing 
           12  component 
           14  stator 
           16  slot 
           20  coil winding 
           22  jump 
           24  wave winding wire 
           24   a  first wave winding wire 
           24   b  second wave winding wire 
           24   c  third wave winding wire 
           24   d  fourth wave winding wire 
           24   e  fifth wave winding wire 
           24   f  sixth wave winding wire 
           26  wave section 
           28  straight wire section 
           30  winding head 
           30   a  first winding head 
           30   b  second winding head 
           32   a  first half-wave section 
           32   b  second half-wave section 
           34   a  first bend point 
           35   b  second bend point 
           34   c  third bend point 
           36  connecting section 
           38   a  first height offset 
           38   b  second height offset 
           38   c  third height offset 
           40  winding mat 
           42  coil mat 
           42 - 1  first exemplary embodiment of coil mat 
           42 - 2  second exemplary embodiment of coil mat 
           42 - 3  third exemplary embodiment of coil mat 
           44   a  first individual mat 
           44   b  second individual mat 
           46  start region 
           48  end region 
           50  flat mat 
           52  transition region 
           54  stair-shaped mat 
           56  standard region 
           58  roof bend 
           60   a  first transition bend 
           60   b  second transition bend 
           62   a  first winding head section 
           62   b  second winding head section 
           62   c  third winding head section 
           64  counter-bend 
           66  wave winding wire supply device 
           68  wave winding wire manufacturing device 
           70  winding head shaping device 
           72  clamping device 
           74 - 1  first clamping unit 
           74 - 2  second clamping unit 
           74 - 3  third clamping unit 
           74 - 4  fourth clamping unit 
           74 - 5  fifth clamping unit 
           76   a  first clamping jaw 
           76   b  second clamping jaw 
           78   a  first bending jaw 
           78   b  second bending jaw 
           80  fixing section 
           82  shaping portion 
           83  bending die 
           86  bending radius 
           88 - 1   a  actuator for first clamping jaw of first clamping unit 
           88 - 1   b  actuator for second clamping jaw of first clamping unit 
           88 - 2   a  actuator for first clamping jaw of second clamping unit 
           88 - 2   b  actuator for second clamping jaw of second clamping unit 
           88 - 3   a  actuator for first clamping jaw of third clamping unit 
           88 - 3   b  actuator for second clamping jaw of third clamping unit 
           88 - 4   a  actuator for first clamping jaw of fourth clamping unit 
           88 - 4   b  actuator for second clamping jaw of fourth clamping unit 
           88 - 5   a  actuator for first clamping jaw of fifth clamping unit 
           88 - 5   b  actuator for second clamping jaw of fifth clamping unit 
           90  control system 
           92 - 1  first clamping surface 
           92 - 2  second clamping surface 
           92 - 3  third clamping surface 
           94  bending unit 
           96  carriage 
           98 - 1   a  first sub-section of first wave winding wire 
           98 - 2   a  second sub-section of first wave winding wire 
           98 - 1   b  first sub-section of second wave winding wire 
           98 - 2   b  second sub-section of second wave winding wire 
           100  crossover point 
           102 - 1   a  first sub-section of first individual mat 
           102 - 2   a  second sub-section of first individual mat 
           102 - 1   b  first sub-section of second individual mat 
           102 - 2   b  second sub-section of second individual mat 
           104  regular exit 
           106  mirrored exit 
           108  series connection 
           110  phase exits 
           112  star points 
         A first conductor 
         B second conductor 
         HM height extension dimension 
         HR 1  first height direction 
         HR 2  second height direction 
         K 1  position adjacent to cross-plugging position 
         K 2  cross-plugging position 
         K 3  position adjacent to cross-plugging position 
         KLM no layer swap possible 
         LM layer swap possible 
         OF upper surface 
         UF lower surface 
         SA stator outer side 
         SI stator inner side 
         SPS coil step 
         STP stacking 
         STK plugging 
         WKH winding head height