CN107546898B

CN107546898B - Connecting device for a stator, electric machine comprising a connecting device and method for producing an electric machine

Info

Publication number: CN107546898B
Application number: CN201710481962.7A
Authority: CN
Inventors: A.皮尔逊; E.J.莫拉莱斯; P.戈伊贝尔
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 2016-06-23
Filing date: 2017-06-22
Publication date: 2021-09-07
Anticipated expiration: 2037-06-22
Also published as: CN107546898A; DE102016211230A1

Abstract

A connecting device for a stator of an electric machine, by means of which an electrical winding of the stator can be connected to a connecting plug for current supply, wherein the connecting device has an insulating plastic body, which is designed as a closed ring, wherein a metallic conductor element is fastened to the plastic body, which conductor element has a welding hook for a welded connection to at least one coil wire of the electrical winding and has a coupling plug for contacting the connection plug, wherein the solder hook is designed as an electrically conductive solder hook component which is produced separately from the connecting plug and which is electrically connected to a separately produced connecting plug component having the connecting plug by means of flexible litz wires, wherein the welding hook member and the coupling plug member are each independently fastened at the plastic body.

Description

Connecting device for a stator, electric machine comprising a connecting device and method for producing an electric machine

Technical Field

The invention relates to a connecting device for a stator of an electric machine, to an electric machine and to a method for producing such a connecting device.

Background

A motor is known from US 20120126646 Al, in which different stator coils are connected with their wire ends to contact elements of a connecting plate. The connection plate has three pins which are connected to the plug-in elements of the electric machine by means of strands. In such an embodiment, a rather cumbersome connecting plate is required, in which a number of different stampings have to be engaged into the connecting plate in order to establish contact with the three coupling plugs. By fitting the strand later on to the connector plug, it is possible, for example, to plug an electronic unit directly onto the connector plug of the connection plate without blind fitting. The assembly process of the electric machine is thus rather complicated and the electrical contacting of the electric machine is effected radially outside the connection plate by means of the strands.

With the unpublished DE1020152000931 an electric machine is known in which a connection plate is axially slipped onto a wound stator body. The conductor elements are fastened to the connection plate as bending stampings which are integrally formed and to which the coil wires are connected, which form a defined interface for user-specific electrical contacting. In the case of such a one-piece conductor element, it is disadvantageous that, during the welding of the conductor element to the coil wire, a mechanical tensioning of the conductor element occurs as a result of the plastic deformation of the welding hook and the heat input, which tensioning changes the predefined position of the coupling plug. This leads to difficulties in the assembly of the user-specific connection plug, which is designed, for example, as an insulation displacement connection.

Disclosure of Invention

Advantages of the invention

The connection device according to the invention and the method according to the invention, which have the features of the invention, have the advantage that, in the welding of the connecting wires of the coil, the connecting pin cannot be detuned by thermal input by structurally separating the welding hook member from the connecting pin.

In contrast, the coupling plugs remain completely unchanged in the plastic body of the connecting plate, so that they can be very reliably plugged into the corresponding electrical mating elements, for example, when the electronic unit is axially slipped onto the connecting plate. By means of the connection via the flexible strand, which is fastened between the solder hook and the coupling plug either before or after the stable welding of the coil wire, the solder hook can be subjected to significantly greater positional tolerances and any considerable heat of the welding process by a type of mechanical decoupling from the coupling plug (i.e. a non-rigid connection), without this affecting the positioning of the coupling plug.

Advantageous modifications and improvements of the embodiments specified in the invention are possible by means of the measures listed in the preferred and further examples. By mechanical decoupling of the solder hook member from the coupling plug, the solder hook member can be configured as a bent stamping, which is optimally configured to the welding process of the connecting lines to the partial coils. In this case, the welding hook member preferably has a support surface with which it rests axially on the plastic body of the connecting plate. By mechanical separation from the coupling plug, all the welding hook members can be identically constructed and only the length of the flexible strand is adapted to the respective position of the coupling plug.

For fastening the welding hook component, a fastening tab is formed at the abutment surface, which fastening tab cooperates with a corresponding mating element in the plastic body. For example, the latch tab catches directly in an axial recess, into which the latch tab engages axially.

In a further embodiment, the contact surface has a continuous axial recess, by means of which the welding hook component is plugged onto a rivet pin, which is integrally formed with the plastic body. In order to securely fasten the welding hook member, the free end of the rivet pin is then plastically deformed by means of heat input, so that a rivet head is formed which presses the contact surface against the connecting plate.

In particular, it is advantageous if the recess of the contact surface is embodied in the form of a slot in the contact plate, so that the welding hook member can be displaced in the radial direction of the stator on a radial line straight towards the welding hook. In this case, the slot is sufficiently wide to allow the rivet pin to pass through completely. By means of such a slot-like design of the cutout of the contact plate, the welding hook component can be adjusted in the welding process itself, for example by reshaping the welding hook, by: the contact surface is matched to its position during the welding process radially to the rivet pin and, if necessary, by rotating around the rivet pin.

Since the coupling plug members are also designed mechanically separately from the welding hook members, the coupling plug members can also all be designed identically, so that the component diversity of the inserts in the connecting plate is significantly reduced. Furthermore, the material and the sheet thickness of the coupling plug member, which is designed as a stamping, can be optimally designed, for example, for an insulation displacement connection which is formed at the axially projecting end of the coupling plug member. By means of the mechanical separation of the welding hook member from the coupling plug member, it is possible to use not only different materials for the respective members, but also different plate thicknesses and/or different material coatings. Also, mechanical stress to the insulation displacement connection can thereby be avoided, so that these high shocks can be stopped and have a long life.

If the coupling plug member is designed as an axial flat web, it can be inserted particularly simply axially into a retaining element formed on the plastic body of the connecting plate. The holding element has, for example, an axial well into which the coupling plug member can be pressed. For axially supporting the coupling plug, the coupling plug component has a crosspiece which is supported at a corresponding axial stop of the holding element. A fork-shaped insulation displacement connector is formed at the axially free end of the coupling plug member, in which a corresponding surface contact of the electronic unit or of the coupling plug can be axially engaged. At the end of the coupling plug member facing the connecting plate, a clamping or latching element is advantageously formed, which is clamped or latched in the retaining element.

By connecting the coupling plug member with the contact plate of the solder hook member, on the one hand a reliable electrical contact can be produced and on the other hand the transmission of stresses between the two members can be hindered. In addition, the length of the flexible strand can be easily varied to span different spacings between the solder hook member and the coupling plug member. The electrically conductive strand is preferably soldered or welded to the two components in order to ensure a permanent and reliable electrical contact.

The flexible strand is advantageously composed of a plurality of individual thin metal wires which are interwoven or twisted with one another. Copper wires are particularly suitable here, since these can be bent very easily and conduct electrical current particularly well. The litz wires are arranged here axially above the plastic ring of the connecting plate and extend in the circumferential direction of the stator.

In the electric machine according to the invention, the stator is wound in such a way that: two directly adjacent stator teeth are wound with in each case exactly one partial coil, which forms a partial coil pairing by means of the continuously wound winding wire. The connecting lines of the immediately adjacently arranged partial coils are guided in the same axial plane of the insulating lamination for all partial coil pairs. In a twelve-tooth stator, for example, six partial coil pairs having six short connecting wires each can be formed, wherein the six short connecting wires each form an interface with the welding hook. In this way, it is possible in a simple manner to optionally form six individual phases with in each case one partial coil pairing or only three phases with in each case two partial coil pairings which are electrically connected to one another. Accordingly, six coupling plugs for six phases or only three coupling plugs for three phases can be formed in the connecting plate in the axial direction. In this case, in only three coupling plugs, in for example six partial coil pairs, two litz wires each are connected to a single coupling plug component. The connecting lines between the individual partial coils are guided in the circumferential direction in guide elements of the stator cage. The welding hook surrounds the connecting wire in a peripheral section, in which the guide element has a recess, so that the connecting wire is guided freely here without it resting somewhere. The welding hooks can thereby completely enclose the connecting wire and, due to the free installation space, the electrode can be brought into contact with the welding hooks not only from the inside but also from the outside in the radial direction.

Particularly advantageously, the connecting device is produced by: the annular connecting plate is first produced as a plastic injection-molded part, wherein a holding element for connecting the plug component and a rivet pin are axially formed thereon. In a separate manufacturing step, the welding hook member is then pushed axially onto the rivet pin and the rivet head is then reshaped in a shaping manner in order to fix the welding hook member firmly on the connecting plate.

Since much heat is introduced into the welding hook member when welding the welding hook to the connecting wire of the coil, the rivet pin or the rivet head can be heated so strongly: so that the weld hook member can easily be radially displaced relative to the riveting pin or turned around the riveting pin. Thereby, it is possible to cause the welding hook member to easily change its position during the welding process, so that no stress occurs between the welding connection and the rivet pin. After cooling down of the welding hook member and the rivet pin, the welding hook member is then again firmly fixed relative to the plastic ring.

The production method according to the invention is particularly suitable for stators in which individual partial coils are continuously wound with a continuous wire, preferably by means of a needle coil. In this case, the stator slots can run, for example, also obliquely to the axial direction. Since the connecting lines between the individual partial coils are guided in the circumferential direction on the insulating laminations of the stator, these can easily be included by the welding hooks, which are fastened to the connecting plate.

In terms of production technology, it is particularly expedient for the flexible strand material to be connected in a bonded manner to the solder hook member and the coupling plug member before this prefabricated structural unit is slipped onto the plastic ring of the stator body. This eliminates the need for heat input into the component due to welding of the stranded wire in the installed state. The preassembled structural unit is fastened to the connecting plate in such a way that: so that the welding hook member is axially pushed onto the riveting pin and the coupling plug member is axially inserted into the respective retaining element. In an alternative embodiment, however, it is also possible for the two components, independently of one another, to be fastened first to the connecting plate and for these components to be subsequently connected to the flexible strand. After the welding hooks have been welded to the connecting wires of the partial coils, an electronic unit or a plug component can be axially joined to the connecting plugs, wherein these connecting plugs can be positioned particularly precisely by the production method according to the invention.

Drawings

Embodiments of the invention are illustrated in the drawings and are explained in more detail in the description that follows. The figure is as follows:

figure 1 is a motor according to the present invention,

FIG. 2 shows a prefabricated inventive structural unit for fitting to the connection plate, and

fig. 3 is another embodiment of a welding hook member.

Detailed Description

In fig. 1, a stator 10 of an electric machine 12 is shown. The stator 10 has a stator body 34, which is composed of individual plate laminations 36, for example. The stator body 34 here comprises an annular closed non-return yoke 38, at which the stator teeth 14 are formed radially inward. Internally, the stator 10 has a circular recess 37 into which a rotor, not shown, can be inserted. The stator teeth 14 extend inwards in the radial direction 4 and along the rotor axis in the axial direction 3. In the exemplary embodiment, the stator teeth 14 are formed overlapping in the circumferential direction 2 in order to reduce the detent torque of the rotor. For this purpose, for example, the plate laminations 36 are correspondingly twisted relative to one another in the circumferential direction 2. An insulating lamination 40 is placed on the axial end face of the stator body 34, around which the winding wire 22 for forming the partial coil 18 of the winding 16 is wound. At least one of the two insulating laminations 40 has an annular closed periphery 41 from which insulating teeth extend in the radial direction 4, which cover the end sides of the stator teeth 14. At the annular circumference 41 of the insulating lamination 40, a guide element 44 is formed, in which the connecting wires 31 are guided between the partial coils 18. For this purpose, the channel 45 is formed in the circumferential direction 2, for example, at the circumferential portion 41, so that the connecting lines 31 are arranged in axially offset planes in order to prevent crossing of the connecting lines 31. In this case, the short connecting lines 31 between two immediately adjacent partial coils 18 (which form the partial coil pairs 17) are arranged in the uppermost axial plane, wherein in particular all connecting lines 31 of the partial coil pairs 17 all run in the same axial plane for contacting the phase connections. In this case, two axial projections 46 are always formed between the two partial coils 18 of the partial coil pair 17 on the insulating lamination 40, which are separated from one another by a radial gap 47 located therebetween. As a result, the short connecting wires 31 of the partial coil pairs 17 are freely accessible from all sides and do not rest against the insulating laminations 40, in particular in the region of the radial recesses 47. If the electrical winding 16 is formed from a plurality of individual winding wires 22 (for a plurality of individual winding bars), the wire start of the first winding bar can run parallel and directly adjacent to the wire end of the first winding bar via the peripheral region of the radial gap 47. By means of this parallel arrangement of the two short connecting lines 31, these can be electrically contacted in the same way as the connecting lines 31 of the continuously wound partial coil pairs 17 for the purpose of actuation. A connecting web 52 is attached to the wound insulating stack 40, by means of which web the electrical winding 16 is actuated. For this purpose, the connecting plate 52 has a coupling plug 54, to which a connector plug 56 of a control unit or of a plug-in component is connected. In this exemplary embodiment, exactly six connection plugs 54 are arranged, which are each electrically connected to a partial coil pairing 17 of the electrical winding 16. Here, six phases are formed by exactly one respective partial coil pair 17, so that the six coupling pins 54 are in contact with the six connecting lines 31 of the adjacent partial coil pair 17.

The connecting plate 52 has a plastic body 62, which is designed as a closed ring 61, by means of which the rotor can be engaged into the recess 37 of the stator 10. A conductor element 58 is arranged on the plastic body 62 and connects the connecting line 31 of the partial coil 18 to the connecting plug 56. The single conductor element 58 comprises in each case one coupling plug member 55, which is produced separately from the solder hook member 66, wherein the two are then electrically connected to one another by means of the movable litz wire 71. In this case, a holding element 63 for the coupling plug 54, which extends away from the stator body 34 in the axial direction 3, is integrally formed on the plastic body 62. The coupling plug 54 is designed, for example, as an insulation displacement connection 57 which has, at its free axial end 68, a recess 76 in which a clamping element of a corresponding connection plug 56 of a cable or electronic unit or of a plug-in component can be engaged. Furthermore, a crosspiece 70 is formed in the radial direction 4 at the coupling plug member 55, said crosspiece being supported in each case at an axial stop 72 of the retaining element 63. Furthermore, a first guide surface and a second guide surface are formed on the holding element 63, which support the coupling plug 54 in two opposite circumferential directions 2. This prevents the coupling plug 54 from being bent or bent longitudinally in the circumferential direction 2 when the connecting plug 56 is engaged, so that axial tolerances of the plug connection are ensured. Likewise, the coupling plug member 55 is also supported in both radial directions 4, preferably by an axial recess 67 in the retaining element 63. In this case, the coupling plug member 55 can be inserted axially into the recess 67 and is braced in the recess 67 by means of a formed clamping or latching element 77. In an exemplary embodiment, for example, two coupling plug members 55 can always be arranged in a common holding element 63, wherein these are separated from one another in the circumferential direction 2 by a central web 82 of the holding element 63. The central webs 82 in this case form guide surfaces on both sides for the respectively resting coupling pins 54. In the region of the holding element 63, spacers 84 are formed axially opposite the latter, which axially support the connecting plate 52 relative to the stator body 34. The connecting plate 52 forms, with the assembled conductor element 58, an electrically actuated connecting device 11 for the electrical winding 16.

A welding hook member 66 configured separately from the coupling plug member 55 is fastened separately at the plastic body 62, for example by form-fitting and/or by means of a latching element 88. In fig. 1, an axial rivet pin 79 is thus formed on the plastic body 62, which rivet pin engages in the welding hook member 66 via an axial recess 80. The welding hook member 66 rests axially with a contact surface 86 against the plastic ring 61 and is fastened to the connecting plate 52 by means of a rivet 81 in a form-fitting manner. The end of the rivet pin 79 can be reshaped by means of heat (in particular ultrasound) into a rivet head 81 which forms a form fit with the welding hook member 66. A welding hook 60 extending radially outward is formed on the welding hook component 66, the radially outer end 65 of which is designed as a noose 64 which encloses the connecting wire 31. Here, the noose 64 is formed of a plate material having a cross-sectional shape that is approximately rectangular. In an embodiment, the solder hook member 66 is formed as a bent stamping from a plate, such as copper. In order to weld the welding hook 60 firmly, the noose 64 is constructed such that its radial end 65 is bent around the connecting line 31. After the open loop 64 has been arranged around the connecting line 31, electrodes are applied, for example, at two diametrically opposite sides of the loop 64, which are pressed together in the radial direction 4 and which are energized for welding the loop 64 to the connecting line 31. Here, the insulating varnish of the connecting wire 31 is melted, so that a firm metallic connection is produced between the welding hook 60 and the connecting wire 31.

The noose 64 is arranged around the connecting line 31 in the region of the radial recess 47, since no guide element 44 is arranged between the connecting line 31 and the noose 64 in this region. As a result, there is sufficient free space for the electrodes to rest against, so that the radial ends 65 of the noose 64 can be pressed against the welding hooks 60, thereby closing the noose 64. In this case, the nooses 64 enclose, in each case according to the partial coil pairs 17, only one single connecting wire 31 or two connecting wires 31 running parallel to one another in parallel, which are formed by the wire start and the wire end of a single winding strand. The flexible strands 71 are connected, preferably welded, in a material-bonded manner on the one hand at the coupling plug member 55 and on the other hand at the solder hook member 66. This prevents mechanical stresses in the conductor element 58 from being transmitted to the coupling plug 54 on account of thermal expansion when the solder hooks 60 are soldered firmly to the connecting wire 31. The litz wires 71 are preferably composed of individual thin copper wires, but other materials with good electrical conductivity can also be used.

For mounting the rotor in the stator 10 shown, a bearing cap, not shown, with a correspondingly shaped axial opening is axially joined to the holding element 63. The coupling plug 54 is then connected to the connection plug 56, which is preferably arranged in an electronic/plug-in module, which in turn is connected to an external current supply. When the housing parts of the electronic/plug-in module are assembled, the coupling plugs 54 can be axially plugged into one another, in particular precisely by means of insulation displacement connections 57.

Fig. 2 shows a conductor element 58 as a prefabricated structural unit 99, which is then joined to the connecting plate 52, as is shown in fig. 1. The flexible strand 71 has a length 73, which enables the coupling plug member 55 and the solder hook member 66 to be fastened individually to the plastic ring 61 in the circumferential direction 2 at a desired distance. After the assembly of the conductor element 58, the litz wire 71 runs along the plastic ring 61, wherein it is guided at a distance from the connecting line 31 of the electrical winding 16. The coupling plug member 55 is designed as an axial web 50, at the free end 68 of which a recess 76 is designed as an insulation displacement connection 57. When the electronic module or plug module is engaged, its connection plug 56 (which, according to the insulation displacement connection 57 in fig. 2, is configured, for example, as a flat plug) can engage in the recess 76. For better fixing and/or guiding of the coupling plug 54 in the corresponding electronic/plug module, a latching hook 53 is formed on the coupling plug 54. In the axially lower region, the coupling plug member 55 has a clamping element 77, which is clamped in place during axial insertion into the axial recess 67 of the holding element 63. The clamping element 77 can be formed by punching or blanking in a stamping process of the coupling plug member 55. A crosspiece 70 is formed axially between the insulation displacement connection 57 and the clamping element 77, for example, in the radial direction 4, and after the axial engagement, said crosspiece axially rests against a corresponding axial stop 72 of the retaining element 63. The strands 71 are welded to the connector plug member 55, the welded connections 78 preferably being arranged axially in the region of the crosspiece 70. The welding hook member 66 has a contact plate 86 which, after its assembly, bears flat axially against the plastic ring 61. At the edge of the contact plate 86, a latching hook 88 is formed, which extends in the axial direction 3. In the latching hooks 88, so-called "fir-tree geometry" 90 is formed, for example, for a latching connection, which hooks into the plastic body 62 when the welding hook members 66 are pressed into the corresponding recesses 67. The strands 71 are firmly welded in this exemplary embodiment to the contact plate 86. The prefabricated conductor elements 58, 99 are mounted on the connection plate 52 by: the weld hook member 66 is secured in the plastic body 62 independent of the coupling plug member 55. Here, a welding hook 60 extends from the contact plate 86 outward in the radial direction 4, the outer radial end 65 of which is designed as an open noose 64. Such an open noose 64 is bent and welded around the respective connecting line 31 after assembly of said welding hook members 66. By means of the mechanically flexible design of the conductor element 58 with the aid of the litz wire 71, the coupling plug 54 can be positioned very precisely in the radial direction 4, in the circumferential direction 2 and in the axial direction 3, without this position being influenced by a later welding process at the welding hook 60.

Fig. 3 shows an alternative embodiment of the welding hook member 66, in which an axial recess 80 is formed in the contact plate 86, through which the rivet pin 79 of the plastic body 62 is axially guided after assembly thereof. The axial recess 80 is formed here as a slot 91 in the radial direction 4, the width 92 of which in the circumferential direction 2 is at least as wide as the diameter 94 of the rivet pin 79. After the welding hook member 66 is fitted over the rivet pin 79, its end is modified into a rivet head 81. Such plastic material modifications are effected, for example, by hot stamping with a hot stamping head and/or by means of ultrasound. Thereby, the welding hook member 66 is firmly fixed to the connecting plate 52, so that the noose 64 of the welding hook 60 can be bent and welded around the connecting line 31. In the secure welding of the welding hook 60, so much heat is introduced into the welding hook member 66: the rivet connection is made so soft that the contact plate 86 is movable within certain limits so as to be rotatable radially along the gap 91 and/or about the rivet pin 79. Thus, during the firm welding of the welding hook 60, a supplementary adjustment of the welding hook member 66 is achieved to some extent: so that the mechanical stresses generated by the bending of the noose 64 and the firm welding of the welding hook 60 are balanced. The litz wire 71 in this example is in contact with the contact plate 86 by means of a welded connection 78 next to the gap 91.

In an alternative embodiment to the preassembled conductor elements 58, 99 according to fig. 2, the litz wires 71 can be connected to these in a bonded manner, for example soldered or welded, if necessary also only after the individual assembly of the coupling plug member 55 and the solder hook member 66. Likewise, the assembly of the conductor elements 58 to the plastic body 62 can alternatively be carried out before or after the assembly of the connection plate 52 to the stator body 34.

It is to be noted that in view of the embodiments shown in the figures and in the description, various combinations of individual features with one another are possible. In this way, the invention relates to the mechanical decoupling of the coupling plug member 55 from the solder hook member 66 by the strand connections 71 of the two

members

55, 66. The specific fastening of the coupling plug member 55 and of the welding hook member 66 to the plastic ring 61 can be varied, as can the specific design, coating and material of the

members

55, 66, which are preferably designed as stampings.

The inventive electric machine 12 is particularly suitable as an embodiment of the EC motor 8 for adjusting a movable component in a motor vehicle, for example for servo steering. Such an electric motor according to the invention can also be installed in a motor compartment, where it is exposed to extreme weather conditions and vibrations.

Claims

1. A connecting device (11) of a stator (10) of an electric machine (12), by means of which connecting device an electrical winding (16) of the stator (10) can be connected to a connecting plug (56) for current supply, wherein the connecting device (11) has an insulating plastic body (62) which is designed as a closed ring (61), wherein a metallic conductor element (58) is fastened to the plastic body (62), said conductor element having, on the one hand, a welding hook (60) for a welded connection to at least one connecting line (31) of the electrical winding (16) and, on the other hand, a coupling plug (54) for contacting the connecting plug (56),

characterized in that the solder hook (60) is designed as an electrically conductive solder hook component (66) which is produced separately from the connection plug (54) and which is electrically connected to a separately produced connection plug component (55) having the connection plug (54) by means of flexible strands (71), wherein the solder hook component (66) and the connection plug component (55) are each fastened separately to the plastic body (62).

2. Connecting device (11) according to claim 1, characterized in that the welding hook member (66) is configured as a bent stamping formed from a sheet metal, at which a flat contact plate (86) is configured, which axially rests against the plastic body (62).

3. Connecting device (11) according to claim 1 or 2, characterized in that latching elements (88) in a fir-tree geometry (90) are formed at the welding hook element (66) which latch or grip into corresponding recesses (89) in the plastic body (62).

4. A connecting device (11) as claimed in claim 2, characterized in that an axial recess (80) is formed in the sheet metal at the contact plate (86), through which recess a rivet pin (79) formed axially on the plastic body (62) extends, the free end of which rivet pin is reformed into a rivet head (81) by means of hot stamping.

5. Connecting device (11) according to claim 1, characterized in that only exactly one slot (91) is formed as a recess (80) in the welding hook component (66), which slot extends radially straight to the welding hook (60), so that the welding hook component (66) is not only radially displaceable but also rotatably formed about the rivet pin (79) during assembly thereof and/or during stable welding of the connecting line (31).

6. The connecting device (11) as claimed in claim 1, characterized in that the coupling plug member (55) is designed as a bent stamping formed from a plate, which bent stamping has an axial web (50) at the axial end of which an insulation displacement connection (57) for a corresponding connecting plug (56) is designed.

7. Connecting device (11) according to claim 6, characterized in that an axially extending retaining element (63) for the coupling plug member (55) is formed at the plastic body (62), wherein the retaining element (63) has an axial stop (72) which extends in the circumferential direction (2) and in the radial direction (4) in order to support a cross-piece (70) of the coupling plug member (55) in the axial direction (3) when the corresponding connection plug (56) is inserted.

8. The connecting device (11) as claimed in claim 6, characterized in that a clamping element (77) is formed at the axial end of the web (50) opposite the insulation displacement connection (57), said clamping element being clamped in the holding element (63) when it is axially inserted into a corresponding axial recess (67) in the holding element.

9. The connecting device (11) as claimed in claim 1, characterized in that the litz wire (71) is connected in a material-bonded manner on the one hand to a contact plate (86) of the solder hook member (66) and on the other hand to the coupling plug member (55).

10. The connecting device (11) as claimed in claim 9, characterized in that the litz wire (71) is welded in a material-bonded manner on the one hand to the contact plate (86) of the welding hook member (66) and on the other hand to the coupling plug member (55).

11. Connecting device (11) according to claim 1, characterized in that the litz wire (71) extends in the circumferential direction (2) along the closed loop (61) of the plastic body (62) and consists of a plurality of thin copper wires.

12. An electrical machine (12) having a connecting device (11) according to one of the preceding claims, having a rotor and a stator (10), characterized in that two partial coils (18) lying directly next to one another are directly connected to one another by means of a connecting wire (31), wherein the connecting wire (31) is designed as a continuously wound winding wire (22) without interruption, wherein an insulating lamination (40) which is designed to be closed on an outer circumference (41) of the insulating lamination (40) and has guide elements (44) for the connecting wire (31) between the individual partial coils (18) is arranged on the uppermost plate lamination (36) of the stator (10), wherein the connecting wire (31) is welded to welding hooks (60) of the conductor elements (58) between directly adjacent partial coil pairings (17) of one phase, wherein the connecting lines (31) are arranged in axially different planes between the partial coils (18), wherein the connecting lines (31) of directly adjacent partial coil pairs (17) of one phase are arranged in the axially uppermost plane.

13. A method for producing a connecting device (11) according to one of claims 1 to 11, characterized in that an annular plastic body (62) is first produced by means of injection molding with a retaining element (63) and a rivet pin (79) integrally formed thereon, and subsequently a separate welding hook component (66) is axially plugged onto the rivet pin (79) and the free end of the rivet pin is reformed into a rivet head (81).

14. Method according to claim 13, characterized in that the rivet pin (79) is warmed and thereby plastically deformable when the welding hook (60) is firmly welded to the connecting wire (31), so that the welding hook member (66) previously fastened to the plastic body (62) is additionally calibrated with respect to radial displacement and twisting around the rivet pin (79) when firmly welding the connecting wire (31).

15. Method according to claim 13, characterized in that partial coils (18) are first wound onto the insulating laminations (40) of the plate laminations (36) of the stator (10), wherein a plurality of partial coils (18) are continuously wound without interruption by means of needle winding, and subsequently connecting means (11) are axially slipped onto the stator (10) in order to firmly weld the connecting wires (31) between the partial coils (18) to the welding hooks (60).

16. Method according to any one of claims 13 to 15, characterized in that a welding hook member (66) is first connected by means of the litz wires (71) with a coupling plug member (55) as a prefabricated structural unit (99) before this prefabricated structural unit (99) is slipped onto the closed ring (61) of the plastic body (62), and thereafter a welding hook (60) is welded to the connecting line (31).